Research Findings - Epidemiology and Etiology Research
Co-twin-control Analysis of SUD Risk Associated With Early-onset Cannabis Use
Researchers assessed whether, after controlling for genetic and shared environmental influences, early cannabis use remains a significant predictor of other drug use, abuse, and dependence, and whether the risk for early-users is greater than that for later cannabis users. Data from a 1992 telephone diagnostic interview of 8169 male twins (M=42.0 years at interview) who served in the U.S. military during the Vietnam-era were used to identify a subsample of 293 monozygotic (MZ) and dizygotic (DZ) twin pairs discordant for early cannabis use (before age 18). Using cotwin-control analyses, outcomes assessed were: lifetime illegal drug use (stimulant/cocaine, sedative, opiate, and hallucinogen/PCP), lifetime DSM-III-R illegal drug abuse/dependence, and lifetime DSM-III-R alcohol dependence. After controlling for covariates, early cannabis users were at greater risk than their later/never-using cotwins for 8 of 9 substance-related comparisons, including: using other illegal drugs (ORs: 2.71-4.09), having illegal drug abuse/dependence (ORs: 2.02-2.13), and developing alcohol dependence (OR=2.36). When analyses were limited to pairs in which the cotwin used cannabis later, early and later-users only differed significantly on sedative, opiate, and hallucinogen use. After familial influences on early cannabis use were controlled for, cannabis use-regardless of the age of initiation-still conferred increased risk of other illegal drug use, drug abuse/dependence, and alcohol dependence. The authors conclude that, in contrast to previous research, there is limited evidence for increased risk associated with early-onset use in this sample of Vietnam-era veterans. Grant J, Lynskey M, Scherrer J, Agrawal A, Heath A, Bucholz K. A Cotwin-Control Analysis Of Drug Use And Abuse/Dependence Risk Associated With Early-Onset Cannabis Use. Addict Behav. 2010; 35 (1): 35-41.
Family Income Supplements in Adolescence Reduced Psychiatric and Substance Use Disorders in Adulthood
This paper follows up a natural experiment in which some families received income supplements and the prevalence of adolescent behavioral symptoms decreased significantly. The adolescents in the prior study are now young adult, and this follow up study examined the effects of income supplements in adolescence and adulthood on the prevalence of adult psychiatric disorders. The study used a quasi-experimental, longitudinal design. The sample consists of a representative sample who were aged 9, 11, or 13 years in 1993 (349 [25%] of whom are American Indian) who were assessed for psychiatric and substance use disorders through age 21 years (1993-2006). Of the 1420 who participated in 1993, 1185 were interviewed as adults. From 1996, when a casino opened on the Indian reservation, every American Indian but no non-Indians received an annual income supplement that increased from $500 to around $9000. Main outcome measures were prevalence of adult psychiatric disorders and substance use disorders based on the Diagnostic and Statistical Manual of Mental Disorders in 3 age cohorts, adjusted for age, sex, length of time in the family home, and number of Indian parents. Results indicated that as adults, significantly fewer Indians than non-Indians had a psychiatric disorder, particularly alcohol and cannabis abuse, dependence, or both. The youngest age-cohort of Indian youth had the longest exposure to the family income. Interactions between race/ethnicity and age cohort were significant. Fewer of the youngest Indian age-cohort had any psychiatric disorder than the Indian middle cohort or oldest cohort or the youngest non-Indian cohort. The income supplement received in adulthood had no impact on adult psychopathology. The authors conclude that lower prevalence of psychopathology in American Indian youth following a family income supplement, compared with the non-exposed, non-Indian population, persisted into adulthood. As the authors note in their discussion, this does not obviate a possible role for genetic factors in the genesis of these disorders, but it strongly suggests that environmental factors can play a key role. Costello E, Erkanli A, Copeland W, Angold A. Association Of Family Income Supplements In Adolescence With Development Of Psychiatric And Substance Use Disorders In Adulthood Among An American Indian Population. JAMA. 2010; 303 (19): 1954-1960.
Methadone Maintenance Therapy Promotes Initiation of Antiretroviral Therapy among Injection Drug Users
Despite proven benefits of antiretroviral therapy (ART), many HIV-infected IDUs do not access treatment even in settings with free health care. Researchers examined whether methadone maintenance therapy (MMT) increased initiation and adherence to ART among an IDU population with free health care. They examined prospectively a cohort of opioid-using antiretroviral-naive HIV-infected IDU and investigated factors associated with initiation of ART as well as subsequent adherence. Factors associated independently with time to first initiation of ART were modelled using Cox proportional hazards regression. Between May 1996 and April 2008, 231 antiretroviral-naive HIV-infected opioid-using IDU were enrolled, among whom 152 (65.8%) initiated ART, for an incidence density of 30.5 [95% confidence interval (CI): 25.9-35.6] per 100 person-years. After adjustment for time-updated clinical characteristics and other potential confounders, use of MMT was associated independently with more rapid uptake of ART [relative hazard = 1.62 (95% CI: 1.15-2.28); P = 0.006]. Those prescribed methadone also had higher rates of ART adherence after first antiretroviral initiation [odds ratio = 1.49 (95% CI: 1.07-2.08); P = 0.019]. These results demonstrate that MMT contributes to more rapid initiation and subsequent adherence to ART among opioid-using HIV-infected IDU. Addressing international barriers to the use and availability of methadone may increase dramatically uptake of HIV treatment among this population. Uhlmann S, Milloy M, Kerr T, Zhang R, Guillemi S, Marsh D, Hogg R, Montaner J, Wood E. Methadone Maintenance Therapy Promotes Initiation Of Antiretroviral Therapy Among Injection Drug Users. Addiction. 2010; 105 (5): 907-913.
Temporal Trends in Highly Active Antiretroviral Therapy Initiation among Injection Drug Users in Baltimore, Maryland, 1996-2008
Researchers characterized temporal trends in highly active antiretroviral therapy (HAART) initiation from 1996 to 2008 among treatment-eligible persons in a community-based cohort of current and former IDUs in Baltimore, Maryland. The study, AIDS Linked to the IntraVenous Experience (ALIVE)) cohort has been observing HIV-positive IDUs since 1988. HAART eligibility was defined as the first visit after 1 January 1996 at which the patient's CD4 (+) cell count was <350 cells/muL. Temporal trends and predictors of HAART initiation were examined using chi (2) tests for trend and lognormal survival models. Data showed that the median age of 582 HAART-eligible IDUs was 41 years; 75% of the subjects were male, 97% were African American, and 60% were active IDUs. Of these 582 individuals, 345 initiated HAART over 1803 person-years (19.2 subjects per 100 person-years; 95% confidence interval, 17.2-21.3 subjects per 100 person-years); there was no statistically significant temporal trend in HAART initiation. Independent predictors of delayed initiation included heavy injection drug use; having a prior AIDS diagnosis, having a lower CD4 (+) cell count, having a usual source of care, and having health insurance were predictors of more-rapid initiation. The delay between eligibility and initiation decreased among those who became eligible most recently (2003-2007), compared with those in earlier periods (1996-2002); however, a substantial number of patients who became eligible in recent years either initiated HAART after a substantial delay or did not initiate HAART at all. This study failed to observe substantial improvement in HAART initiation among current and former IDUs over a 12-year period; heavy use of injection drugs remains the major barrier to HAART initiation and to consistent HIV care. The fact that many IDUs initiate HAART after a significant delay or do not initiate it at all raises concern that disparities in HIV care for IDUs remain at a time of simplified antiretroviral regimens and increasing adoption of earlier treatment. Mehta SH, Kirk GD, Astemborski J, Galai N. Temporal Trends In Highly Active Antiretroviral Therapy Initiation Among Injection Drug Users In Baltimore, Maryland, 1996-2008. Clin Infect Dis. 2010; 50 (12): 1664-1671.
Flashblood: Blood Sharing among Female Injecting Drug Users in Tanzania
This cross-sectional study examined the association between the blood-sharing practice of ''flashblood'' use and demographic factors, HIV status, and variables associated with risky sex and drug behaviors among female IDUs in Dar es Salaam, Tanzania. Flashblood is a syringe-full of blood passed from someone who has just injected heroin to someone else who injects it in lieu of heroin. One hundred and sixty-nine female IDUs were recruited using purposive sampling for hard-to-reach populations. The t-test and chi(2) test were used to analyze associations between flashblood use, demographic and personal characteristics and risky sex and drug use variables. The association between flashblood use and residential neighborhood was also mapped. Flashblood users were found more likely to: be married (P = 0.05), have lived in the current housing situation for a shorter time (P < 0.000), have been forced as a child to have sex by a family member (P = 0.007), inject heroin more in the last 30 days (P = 0.005), smoke marijuana at an earlier age (P = 0.04), use contaminated rinse-water (P < 0.03), pool money for drugs (P < 0.03) and share drugs (P = 0.000). Non-flashblood users were more likely to live with their parents (P = 0.003). Neighborhood flashblood use was highest near downtown and in the next two adjoining suburbs and lowest in the most distant suburbs. These data indicate that more vulnerable women who are also heavy users of drugs and live in shorter-term housing are injecting flashblood. The practice of flashblood now appears to be spreading from the inner city to the suburbs of Dar es Salaam. McCurdy SA, Ross MW, Williams ML, Kilonzo GP, Leshabari MT. Flashblood: Blood Sharing Among Female Injecting Drug Users In Tanzania. Addiction. 2010; 105: 1062-1070.
HIV Infection during Limited Versus Combined HIV Prevention Programs for IDUs in New York City: The Importance of Transmission Behaviors
As no single HIV prevention program has eliminated HIV transmission, there is growing interest in the effectiveness of "combined" prevention programming. In this study, researchers sought to compare HIV infection among persons injecting in the initial programs environment (IPE) in New York City (i.e., self-initiated risk reduction, methadone, education/outreach, and HIV testing) to HIV infection among persons injecting in a combined programs environment (CPE) (i.e., the above programs plus large-scale syringe exchange) to identify potential behavioral mechanisms through which combined programs are effective. Subjects were recruited for the study from the Beth Israel drug detoxification program, where a risk behavior questionnaire was administered and HIV testing was conducted. Subjects (n=261) who injected only between 1984 and 1994 (IPE) were compared to those (n=1153) who injected only between 1995 and 2008 (CPE). HIV infection was found to be significantly lower among CPE subjects compared to IPE subjects: prevalence 6% versus 21%, estimated incidence 0.3/100 person-years versus 4/100 person-years (both p<0.001). The percentage of subjects at risk of acquiring HIV through receptive syringe sharing was similar across CPE and IPE subjects (30% versus 33%). The percentage of subjects at risk of transmitting HIV through injection-related behaviors (i.e., who were both HIV seropositive and reported passing used needles/syringes to others) was much lower among the CPE subjects than among the IPE subjects (1% versus 10%, p<0.001). These analyses indicate that combined prevention programs can greatly reduce HIV transmission risks. Additional efforts to reduce distributive sharing by HIV seropositive injecting drug users (IDUs) may be needed, given that this is a critical behavior in HIV transmission in high seroprevalence settings. Des Jarlais DC, Arasteh K, McKnight C, Hagan H, Perlman D, Torian L, Beatice S, Semaan S, Friedman S. HIV Infection During Limited Versus Combined HIV Prevention Programs For IDUs In New York City: The Importance Of Transmission Behaviors. Drug Alcohol Depend. 2010;109 (1-3): 154-160.
A Longitudinal Study of Sexual Risk Behavior among the Adolescent Children of HIV-positive and HIV-negative Drug-abusing Fathers
This is a longitudinal study of the precursors of sexual risk behavior among a cohort of adolescent children of HIV-positive and HIV-negative drug-abusing or drug-dependent fathers. Individual structured interviews were administered to 296 drug-abusing or drug-dependent fathers, 43% of whom were HIV positive, and an adolescent child of each father (mean age = 16.3 years; SD = 2.8). Adolescents were re-interviewed approximately one year later, at Time 2. Structural equation modeling showed multiple direct and indirect pathways from psychosocial factors to adolescent sexual risk behavior (sexually active, number of sexual partners and frequency of condom use). Greater paternal drug addiction and infection with HIV/AIDS, and the youth's perception of environmental hostility (discrimination and victimization), were both related to increased adolescent maladjustment and substance use. Greater paternal drug addiction and infection with HIV/AIDS also were associated with a weaker father-child mutual attachment, which was linked with increased adolescent maladjustment and substance use. Greater perceived environmental hostility (discrimination and victimization), a weak father-child relationship, and greater adolescent maladjustment and substance use had direct pathways to adolescent sexual risk behavior. Findings suggest complex interrelationships among paternal, environmental, social, personal, and substance use factors as longitudinal predictors of sexual risk behavior in children whose fathers abuse or are dependent upon drugs. The importance of perceived environmental hostility, the father-child relationship, and adolescent maladjustment and substance use may have implications for public policy as well as prevention and treatment programs. Brook D, Brook J, Rubenstone E, Zhang C, Finch S. A Longitudinal Study Of Sexual Risk Behavior Among The Adolescent Children Of HIV-Positive And HIV-Negative Drug-Abusing Fathers. J Adolesc Health. 2010; 46(3): 224-231.
Discrimination, Psychosocial Stress, and Health Among Latin American Immigrants in Oregon
Chronic psychosocial stress related to discrimination has been shown to be associated with biological measures such as elevated systolic blood pressure (SBP), increased body fat, and higher fasting glucose levels. Few studies have examined these relationships in immigrant populations. The present study recruited a sample of 132 Oregon Latino immigrant adults to investigate the relationships between perceived discrimination and several health measures (blood pressure, body mass index [BMI], and fasting glucose). Results indicate that perceived discrimination stress predicted elevated SBP among men but not among women. Perceived discrimination was significantly higher among obese women than among women of normal BMI. The same pattern was not observed for men. Further, a strong trend relationship was detected: the higher women's reported discrimination stress, the higher their fasting glucose levels. Again, this pattern was not observed for men. These results suggest that chronic psychosocial stress plays an important role in disease risk among Latin American immigrants, and that male and female immigrants may have distinctive physiological responses. If confirmed, these findings may have important clinical and public health implications for chronic disease prevention among Latinos. McClure H, Snodgrass J, Martinez C, Eddy J, Jiménez R, Isiordia L. Discrimination, Psychosocial Stress, And Health Among Latin American Immigrants In Oregon. Am J Hum Biol. 2010; 22(3): 421-423.
Sharing and Selling of Prescription Medications in a College Student Sample
The aims of this study were to: 1) estimate the prevalence of prescription medication diversion among college students; 2) to compare classes of medications with respect to the likelihood of diversion; 3) document the most common methods of diversion; and, 4) examine the characteristics of students who diverted medications. To pursue these aims, investigators conducted a cross-sectional analysis of personal interview data collected between August 2006 and August 2007 as part of an ongoing longitudinal study. The cohort of students, who were between the ages of 17 and 19 years at study onset, attended a large public university in the mid-Atlantic region. Information was gathered regarding a wide variety of variables, including demographics, diversion of medically prescribed drugs, illicit drug use, and childhood conduct problems. Results showed that among 483 students prescribed a medication, 35.8% diverted a medication at least once in their lifetime. The most commonly diverted medication classes were prescription attention-deficit/hyperactivity disorder medication (61.7% diversion rate) and prescription analgesics (35.1% diversion rate). Sharing was the most common method of diversion, with 33.6% of students sharing their medication(s) and 9.3% selling in their lifetime. Comparative analyses revealed that prescription medication diverters had used more illicit drugs in the past year and had more childhood conduct problems than non-diverters. The authors conclude that these findings may have important clinical implications for improved physician-patient communication and vigilance regarding prescribing analgesic and stimulant medications for young adults. Garnier L, Arria A, Caldeira K, Vincent K, O 'Grady K, Wish E. Sharing And Selling Of Prescription Medications In A College Student Sample. J Clin Psychiatry. 2010; 71 (3): 262-269.
Anxiety as Predictor of First Use of Substances and Progression to SUD Among Boys
This study examined associations of generalized and social anxiety with age at first use of tobacco, alcohol, and marijuana and the interval from first use to first problem use of each substance. Participants were 503 males who comprised the youngest cohort (first assessed in the first grade) of the Pittsburgh Youth Study, a longitudinal community-based study of boys. Annual assessments of generalized and social anxiety, delinquency, and substance use from first grade through high school were included. The authors found that both types of anxiety predicted earlier first use of alcohol and tobacco, and generalized anxiety predicted earlier first use of marijuana. Both types of anxiety predicted the progression from first use to problems related to marijuana. The effect of generalized anxiety tended to be significant above and beyond the effect of delinquency, while the effect of social anxiety on risk for first use of substances was not. Overall, the findings suggest that associations between anxiety and substance use and related problems depend on the class of substance and the type of anxiety. Marmorstein N, White H, Loeber R, Stouthamer-Loeber M. Anxiety As A Predictor Of Age At First Use Of Substances And Progression To Substance Use Problems Among Boys. J Abnorm Child Psychol. 2010; 38(2): 211-224.
Nonmedical Use of Promethazine Hydrochloride among Heroin Injectors in Vietnam: Unrecognized Risks and Unintended Consequences
Surveillance studies have noted intravenous injection of promethazine hydrochloride (PHC) among populations that use heroin in South and Southeast Asia. However, little is known about onset and initiation of PHC use and its relationship to habitual heroin use. As part of a longitudinal study of heroin initiation, a sample of 179 new heroin users, aged 15-27 years, were interviewed between October 2005 and December 2006 in Hanoi, Vietnam. Cox proportional hazard regression analysis was used to characterize age at promethazine initiation and its association with relevant covariates. 76% reported lifetime use of PHC. Mean age of PHC initiation was 21.3 years, on average 6 months following onset of heroin injection. In multivariate analysis, lifetime use of diazepam [HR = 1.69 (1.17, 2.44); p-value = .01] and injecting heroin for more than 1.58 years [HR = 1.46 (1.04, 2.06); p-value = .03] were associated with PHC initiation. Intravenous injection of PHC is a relatively common practice among young injection heroin users in Hanoi, Vietnam who use it on a situational basis to substitute for heroin (when heroin is not available or when heroin is too costly) or to augment the effects of an inadequate heroin dosing (delaying onset of heroin withdraw). Existing drug prevention strategies in Vietnam are focused primarily on heroin and most new heroin users initiate PHC use without prior knowledge of its high risk for serious vein damage. Future research is needed on the PHC use among heroin users, including long-term medical consequences of PHC exposure. Clatts M, Giang L, Goldsamt L, Colón-López V. Nonmedical Use Of Promethazine Hydrochloride Among Heroin Injectors In Vietnam: Unrecognized Risks And Unintended Consequences. Subst Use Misuse. 2010; 45(4): 515-527.
Prevalence and Incidence of HCV Infection among Vietnam Heroin Users with Recent Onset of Injection
HCV infection continues to spread at an alarming rate among IDU populations. The available evidence suggests that HCV is acquired relatively quickly following onset of injection. However, there are few prospective studies of HCV acquisition, particularly among IDU populations in resource-poor settings. A sample of young male heroin injectors with recent onset of injection (<4 years) was recruited in Hanoi, Vietnam for a prospective assessment of the early course of injection (n = 179). Both behavioral and biological assessments (including detailed retrospective assessment of injection initiation) were conducted at baseline and repeated at 6-month intervals for a period of 16 months. Variables associated with HCV infection (p value < 0.05) in bivariate analyses were considered for inclusion in logistic regression models to identify risk factors independently associated with HCV infection. HCV incidence was calculated by using the incidence density approach and was expressed in terms of person-years of observation. The baseline of prevalence of HCV was 46%. HCV significantly increased in relation to time since first injection, from 30% in subjects with =30 months injection risk (p value = 0.0005). In multivariate logistic regression analysis, increasing age, incarceration in a drug detention facility (OR = 2.54; 95% CI 1.05, 6.15), and time since first injection remained significantly associated with HCV infection. Use of injection as primary mode of administration (OR = 2.56; 95% CI 0.98, 6.69) achieved marginal significance. After 16 months of follow-up, the incidence rate of HCV was 23.35 per 100 person-years and the mean time between first injection and first positive HCV test was 1.2 years. HCV is acquired much more rapidly among new injector populations than previously recognized, demonstrating the need for early behavioral intervention among new heroin-user populations. Particularly critical are interventions that target new heroin user populations, including interventions that improve understanding of viral transmission dynamics, that promote alternative strategies for drug sharing, and that delay initiation of injection. Clatts M, Colón-López V, Giang L, Goldsamt L. Prevalence and Incidence of HCV Infection Among Vietnam Heroin Users With Recent Onset Of Injection. J Urban Health. 2010; 87(2): 278-291.
Offer of Financial Incentives for Unprotected Sex in the Context of Sex Work
Commercial sex workers (CSW) are often portrayed as vectors of disease transmission. However, the role clients play in sexual risk taking and related decision making has not yet been thoroughly characterized. In this study, participants were from the Vancouver Injection Drug Users Study, a longitudinal cohort. Analyses were restricted to those who reported selling sex between June 2001 and December 2005. Using multivariate generalized estimating equation, researchers evaluated the prevalence of and factors associated with being offered money for sex without a condom. A total of 232 CSW were included in the analyses, with 73.7% reporting being offered more money for condom non-use, and 30.6% accepting. Variables independently associated with being offered money for sex without a condom included daily speedball use [adjusted odds ratio (AOR) = 1.21, 95% confidence interval (CI): 0.23-0.62], daily crack smoking (AOR = 1.51, 95% CI: 1.04-2.19), daily heroin injection (AOR = 1.76, 95% CI: 1.27-2.43) and drug use with clients (AOR = 3.22, 95% CI: 2.37-4.37). HIV seropositivity was not significant (AOR = 0.98, 95% CI: 0.67-1.44). These findings highlight the role clients play in contributing to unprotected sex through economic influence and exploitation of CSW drug use. HIV serostatus has no bearing on whether more money is offered for sex without a condom. Novel interventions are needed to engage both CSW and clients in risk reduction and consistency in safe sex practices. Johnston C, Callon C, Li K, Wood E, Kerr T. Offer Of Financial Incentives For Unprotected Sex In The Context Of Sex Work. Drug Alcohol Rev. 2010; 29(2): 144-149.
Community-Associated Methicillin-Resistant Staphylococcus aureus is Prevalent in Wounds of Community-Based Injection Drug Users
Injection drug users (IDUs) have an elevated risk for carriage of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). Cutaneous injection-related infections are common in IDUs but detailed studies are few. Based on a subsample of 218 individuals from a community-recruited cohort of IDUs at a supervised injection facility, researchers investigated the microbiology and related antibiotic susceptibility profiles of isolates from 59 wounds. Twenty-seven percent of subjects had at least one wound and 25 (43%) were culture positive for S. aureus alone [14 MRSA and 11 (19%) methicillin-susceptible (MSSA) isolates]. Sixteen of 18 MRSA isolates were classified as community associated (CA) by the presence of genes encoding for PVL. MRSA and MSSA occurred in mixed infection with other organisms on three and six occasions, respectively. All CA-MRSA isolates were susceptible to tetracycline, vancomycin and linezolid but only 13% were susceptible to clindamycin compared to 63% of MSSA isolates. The frequency of CA-MRSA is a cause for public health concern in wound infection in the IDU setting. Lloyd-Smith E, Hull M, Tyndall M, Zhang R, Wood E, Montaner J, Kerr T, Romney M. Community-Associated Methicillin-Resistant Staphylococcus Aureus Is Prevalent In Wounds Of Community-Based Injection Drug Users. Epidemiol Infect. 2010; 138(5): 713-720.
Non-Injection Drug Use Patterns and History of Injection among Street Youth
Efforts to prevent youth from initiating injection drug use require a better understanding of drug use patterns that may predispose to injecting. Here researchers identify such patterns and describe the circumstances of first injection among street youth. From October 2005 to November 2007, data were collected for the At Risk Youth Study. A prospective cohort of 560 street-recruited youth aged 14-26 in Vancouver, Canada. Non-injection drug use behaviors were compared between those with and without a history of injection through multiple logistic regression. The circumstances of first injection were also examined in gender-stratified analyses. Youth who had previously injected were more likely to have engaged in non-injection use of heroin or of crystal methamphetamine. Daily users of marijuana were less likely to have injected. Among prior injectors, the median age of first injection was lower among females. Females were also more likely to have had a sexual partner present at first injection and to have become a regular injector within one week of initiation. These data show that preventing transition to injection among street youth will likely require special attention to predisposing drug use patterns and knowledge of how gender differences can influence the circumstances of first injection. Hadland S, Kerr T, Marshall B, Small W, Lai C, Montaner J, Wood E. Non-Injection Drug Use Patterns and History of Injection Among Street Youth. Eur Addict Res. 2010; 16(2): 91-98.
Late Presentation for HIV Care in the United States and Canada
Initiatives to improve early detection and access to HIV services have increased over time. Researchers assessed the immune status of patients at initial presentation for HIV care from 1997 to 2007 in 13 US and Canadian clinical cohorts. They analyzed data from 44,491 HIV-infected patients enrolled in the North American-AIDS Cohort Collaboration on Research and Design. They identified first presentation for HIV care as the time of first CD4 (+) T lymphocyte (CD4) count and excluded patients who, prior to this date, had HIV RNA measurements, evidence of antiretroviral exposure, or a history of AIDS-defining illness. Trends in mean CD4 count (measured as cells/mm (3)) and 95% confidence intervals were determined using linear regression, adjusted for age, sex, race/ethnicity, HIV transmission risk, and cohort. Median age at first presentation for HIV care increased over time (range, 40-43 years), whereas the percentage of patients with injection drug use HIV transmission risk decreased (from 26% to 14%) and heterosexual transmission risk increased (from 16% to 23%). Median CD4 count at presentation increased from 256 cells/mm (3) (interquartile range, 96-455 cells/mm (3)) to 317 cells/mm (3) (interquartile range, 135-517 cells/mm (3)) from 1997 to 2007. The percentage of patients with a CD4 count > or = 350 cells/mm (3) at first presentation also increased from 1997 to 2007 (from 38% to 46%). The estimated adjusted mean CD4 count increased at a rate of 6 cells/mm (3) per year (95% confidence interval, 5-7 cells/mm (3) per year). CD4 count at first presentation for HIV care has increased annually over the past 11 years but has remained <350 cells/mm (3), which suggests the urgent need for earlier HIV diagnosis and treatment. Althoff K, Gange S, Klein M, Brooks J, Hogg R, Bosch R, Horberg M, Saag M, Kitahata M, Justice A, Gebo K, Eron J, Rourke S, Gill M, Rodriguez B, Sterling T, Calzavara L, Deeks S, Martin J, Rachlis A, Napravnik S, Jacobson L, Kirk G, Collier A, Benson C, Silverberg M, Kushel M, Goedert J, McKaig R, Van Rompaey S, Zhang J, Moore R. Late Presentation For HIV Care In The United States And Canada. Clin Infect Dis. 2010; 50(11): 1512-1520.
Heterosexual HIV and Sexual Partnerships between Injection Drug Users and Noninjection Drug Users
Sex partnerships with injection drug users (IDU) are an understudied network-level risk factor for heterosexual HIV infection. Heterosexuals with no history of injection were recruited from high-risk areas in New York City through respondent-driven sampling. Researchers examined the prevalence of IDU sex partnerships among these non-IDU, factors associated with having a past year IDU partner, and the independent association of HIV infection and IDU sex partnerships in multiple logistic regression. Of the 601 non-IDU in this analysis, 13.8% had a sex partner in the past year with a history of injection. IDU partnerships were significantly more common among women and those with higher levels of unprotected sex and drug and alcohol use. Overall, 7.0% tested positive for HIV. HIV prevalence was higher (p = 0.07) for participants with IDU partners (9.6%) compared to those with no IDU partners (4.6%). In multiple logistic regression, participants with IDU partners were over twice as likely to be HIV-infected (p = 0.08). Sex partnerships with IDU were common and may play an important role in heterosexual HIV transmission in areas with large IDU populations. Prevention interventions to encourage the disclosure of injection history and risk reduction specifically for those with IDU partners are indicated. Jenness S, Neaigus A, Hagan H, Murrill C, Wendel T. Heterosexual HIV And Sexual Partnerships Between Injection Drug Users And Noninjection Drug Users. AIDS Patient Care STDS. 2010; 24(3): 175-181.
Hepatitis Vaccination of Men who have Sex with Men at Gay Pride Events
Prevention researchers have advocated primary prevention such as vaccination in alternative venues. However, there have been major questions about both the attendance of, and the ability to, vaccinate high-risk individuals in such settings. The current study seeks to assess the feasibility of vaccinating high-risk men who have sex with men (MSM) at Gay Pride events. The research questions are: Do gay men who are sampled at Gay Pride events engage in more or less risky behavior than gay men sampled at other venues? Do the gay men who receive hepatitis vaccinations at Gay Pride events engage in more or less risky behavior than gay men at these events who do not receive hepatitis vaccination? Of the 3689 MSM that completed the Field Risk Assessment (FRA), 1095/3689 = 29.68% were recruited at either the 2006 or 2007 Long Beach, California Gay Pride events. The remaining, 2594/3689 = 70.32% were recruited at Long Beach gay bars, gay community organizations and institutions, and through street recruitment in various gay enclaves in the Long Beach area. Logistic regression analysis yielded eight factors that were associated with non-attendance of Gay Pride: Age, had sex while high in the last 12 months, had unprotected anal intercourse (UAI) in the last 12 months, had sex for drugs/money in the last 12 months, been diagnosed with a sexually transmitted infection (STI) in the last 12 months, used nitrites (poppers) in the last 12 months, and used methamphetamine in the last 12 months. Identifying as White, Asian, or African American compared to Hispanic was also associated with non-attendance. Bivariate analysis indicated that, of the MSM sampled at Gay Pride, 280/1095 = 25.57% received a hepatitis vaccination there. The MSM sampled at Gay Pride who reported engaging in UAI or having used any stimulant (cocaine, crack-cocaine, or methamphetamine) in the last 12 months were more likely to receive hepatitis vaccination on-site. The results provide evidence for the viability of successfully vaccinating high-risk MSM at Gay Pride events. However, it is vital that no-cost vaccinations are also funded in other community settings such as STI clinics, drug treatment programs, prisons, universities, and other community resource centers in order to reach those additional high-risk MSM who do not attend Gay Pride. Storholm E, Fisher D, Reynolds G, Napper L, Morrisse T, Kochems L. Hepatitis Vaccination Of Men Who Have Sex With Men At Gay Pride Events. Prev Sci. 2010; 11(2): 219-227.
Modeling the Effect of High Dead-Space Syringes on the HIV Epidemic among Injecting Drug Users
Researchers sought to illustrate the impact of different proportions of injecting drug users (IDUs) sharing high dead-space syringes (HDSS) or low dead-space syringes (LDSS) on the probability of HIV transmission, and thus the impact on injection-related HIV prevalence and incidence. A stochastic mathematical model was used to evaluate the impact of HDSS use in high- and low-risk IDU populations. Model parameters were obtained from peer-reviewed publications. Analytical solutions of a simplified deterministic model were obtained to explain the effect of HDSS on HIV endemic states. Simulation analysis showed that the HIV epidemic could be sustained even when a small percentage of sharing (10%) involved HDSS. The effect is much stronger in high-risk compared with low-risk populations. Steady state HIV prevalence increases with the proportion of HDSS, and for high- and low-risk populations reaches around 80% and 20%, respectively. For low-risk populations, the use of LDSS could result in the virtual elimination of HIV. These results are dependent upon an evidence-supported assumption of a significant difference in HIV transmission risk associated with HDSS versus LDSS. These models suggest that injection-related HIV epidemics may not occur in situations where most (e.g. 95% or more) IDUs use LDSS. While the results are based on indirect risk measures and a number of simplifying assumptions, the effect of blood retained in high dead-space syringes on HIV prevalence is strong, even under relatively conservative assumptions. These findings have potential implications for needle exchange programs and the types of syringes produced and distributed world-wide. Bobashev GV, Zule WA. Modeling the Effect of High Dead-Space Syringes on the HIV Epidemic among Injecting Drug Users. Addiction. 2010; e1-e9.
Cost-Effectiveness of Strategies to Improve HIV Testing and Receipt of Results: Economic Analysis of a Randomized Controlled Trial
CDC recommends routine voluntary HIV testing of all patients 13-64 years of age. Despite this recommendation, HIV testing rates are low even among those at identifiable risk, and many patients do not return to receive their results. This study sought to examine the costs and benefits of strategies to improve HIV testing and receipt of results by analyzing cost-effectiveness based on a Markov model. Data on acceptance of testing, return rates, and related costs were derived from a randomized trial of 251 primary care patients with unknown HIV status; data on long-term costs and health outcomes were derived from the literature. The analysis compared three intervention models for HIV counseling and testing: Model A = traditional HIV counseling and testing; Model B = nurse-initiated routine screening with traditional HIV testing and counseling; Model C = nurse-initiated routine screening with rapid HIV testing and streamlined counseling. The main measures were life-years, quality-adjusted life-years (QALYs), and costs and incremental cost-effectiveness. Researchers found that, without consideration of the benefit from reduced HIV transmission, Model A resulted in per-patient lifetime discounted costs of $48,650 and benefits of 16.271 QALYs. Model B increased lifetime costs by $53 and benefits by 0.0013 QALYs (corresponding to 0.48 quality-adjusted life days). Model C cost $66 more than Model A with an increase of 0.0018 QALYs (0.66 quality-adjusted life days) and an incremental cost-effectiveness of $36,390/QALY. When the benefit was included from reduced HIV transmission, Model C cost $10,660/QALY relative to Model A. The cost-effectiveness of Model C was robust in sensitivity analyses. In a primary-care population, nurse-initiated routine screening with rapid HIV testing and streamlined counseling increased rates of testing and receipt of test results and was cost-effective compared with traditional HIV testing strategies. Sanders G, Anaya H, Asch S, Hoang T, Golden J, Bayoumi A, Owens D. Cost-Effectiveness Of Strategies To Improve HIV Testing And Receipt Of Results: Economic Analysis Of A Randomized Controlled Trial. J Gen Intern Med. 2010; 25(6): 556-563.
Parent Alcoholism Impacts the Severity and Timing of Children's Externalizing Symptoms
Although previous studies show that children of alcoholic parents have higher rates of externalizing symptoms compared to their peers, it remains unclear whether the timing of children's externalizing symptoms is linked to that of their parent's alcohol-related symptoms. Data were from 3 cohorts in the Michigan Longitudinal Study of children from alcoholic parents as well as children from matched, contrasting families without an alcoholic parent. In total, 596 children from 338 families provided four waves of data (ages 2-17). Using a multilevel modeling approach, researchers tested whether the children showed elevated mother-, father- and child-reported externalizing symptoms (a) at the same time that parents showed alcohol-related consequences (time-varying effects), (b) if parents showed greater alcohol-related consequences during the study period (proximal effects), and (c) if parents had a lifetime diagnosis of alcoholism that predated the study period (distal effects). Findings indicated that distal effects of parent alcoholism on increases in child externalizing symptoms were large and consistent. Proximal and time-varying effects of parent alcohol symptoms were found, but were not as large as distal effects. The implications of these findings for preventing escalations in externalizing symptoms among the children of alcoholic parents include the need for family-based programs that consider both distal and proximal impacts of parental alcoholism on children's functioning over development. Hussong A, Huang W, Curran P, Chassin L, Zucker R. Parent Alcoholism Impacts The Severity And Timing Of Children's Externalizing Symptoms. J Abnorm Child Psychol. 2010; 38(3): 367-380.
Developmental Associations between Depression and SUD
The association between depression and substance dependence is poorly understood; examinations of these two disorders over time during key developmental periods can provide insight into how they relate to each other. The goal of this study was to examine longitudinal associations between depression and substance (alcohol and illicit drug) dependence during the period from adolescence through early adulthood. Data from the Minnesota Twin Family Study, a community-based sample of 1252 youth and their families, were used. Youth were first assessed at age 17; they returned to the study at ages 20 and 24. Major depression and drug and alcohol dependence were assessed via structured interviews. Gender was examined as a possible moderator. The results indicated that both substance dependence and depression showed stability over time -- that is, each disorder was associated with increased risk for the same disorder later. Substance dependence between ages 17 and 20 predicted increased risk of depression between ages 20 and 24. These associations did not differ significantly by gender. The authors conclude that substance dependence during late adolescence predicts the subsequent occurrence of major depression. Marmorstein N, Iacono W, Malone S. Longitudinal Associations Between Depression And Substance Dependence From Adolescence Through Early Adulthood. Drug Alcohol Depend. 2010; 107(2-3): 154-160.
The Causal Impact of Childhood-Limited Maltreatment and Adolescent Maltreatment on Early Adult Adjustment
This study used full-matching propensity score models to test whether developmentally specific measures of maltreatment, in particular childhood-limited maltreatment versus adolescent maltreatment, are causally related to involvement in crime, substance use, health-risking sex behaviors, and internalizing problems during early adulthood. The design included 907 participants (72% male) in the Rochester Youth Development Study, a community sample followed from age 14 to age 31 with 14 assessments, including complete maltreatment histories from Child Protective Services records. After balancing the data sets, childhood-limited maltreatment was found to be significantly related to drug use, problem drug use, depressive symptoms, and suicidal thoughts. Maltreatment during adolescence had a significant effect on a broader range of outcomes: official arrest or incarceration, self-reported criminal offending, violent crime, alcohol use, problem alcohol use, drug use, problem drug use, risky sex behaviors, self-reported sexually transmitted disease diagnosis, and suicidal thoughts. The causal effect of childhood-limited maltreatment was focused on internalizing problems, whereas adolescent maltreatment had a stronger and more pervasive effect on later adjustment. Increased vigilance by mandated reporters, especially for adolescent victims of maltreatment, along with provision of appropriate services, may prevent a wide range of subsequent adjustment problems. Thornberry T, Henry K, Ireland T, Smith C. The Causal Impact Of Childhood-Limited Maltreatment And Adolescent Maltreatment On Early Adult Adjustment. J Adolesc Health. 2010; 46(4): 359-365.
Impact of Adolescent Exposure to Intimate Partner Violence on Substance Use in Early Adulthood
Youth exposure to intimate partner violence has been theorized to increase the risk of adverse outcomes in adulthood including substance-use problems. However, research on the association between early exposure to intimate partner violence and later alcohol- or drug-use problems is limited and inconclusive. Using a prospective design, this study investigates whether adolescent exposure to intimate partner violence increases the risk for problem substance use in early adulthood and whether this relationship differs by gender. The study is based on a subsample (n = 508) of participants from the Rochester Youth Development Study, a longitudinal study of urban, largely minority adolescents that oversampled youth at high risk for antisocial behavior and drug use. Logistic regression analyses were conducted to assess whether adolescent exposure to intimate partner violence predicted increased odds of four indicators of problem substance use in early adulthood, controlling for parental substance use, adolescent maltreatment, and socio-demographic risk factors. Exposure to severe intimate partner violence as an adolescent significantly increased the odds of alcohol-use problems in early adulthood for young women (OR = 5.63, p <.05) but not for young men. Exposure to intimate partner violence did not increase the odds of other substance-use indicators for either gender. Girls exposed to intimate partner violence may be at increased risk for problems with alcohol use in adulthood and should be targeted for prevention and intervention efforts. Overall, however, the association between exposure to intimate partner violence and later substance-use problems was less than expected in this high-risk community sample. Smith C, Elwyn L, Ireland T, Thornberry T. Impact of Adolescent Exposure To Intimate Partner Violence on Substance Use In Early Adulthood. J Stud Alcohol Drugs. 2010; 71(2): 219-230.
A Parallel Process Model of the Development of Positive Smoking Expectancies and Smoking Behavior During Early Adolescence in Girls
This study examined the development of positive smoking expectancies and smoking behavior in an urban cohort of girls followed annually over ages 11-14. Longitudinal data from the oldest cohort of the Pittsburgh Girls Study (N = 566, 56% African American, 44% Caucasian) were used to estimate a parallel process growth model of positive smoking expectancies and smoking behavior. Average level of positive smoking expectancies was relatively stable over ages 11-14, although there was significant variability in initial level and rate of change in positive smoking expectancies. Ethnicity was associated with expectancy intercept and slope, such that African American, relative to Caucasian, girls initially had more positive expectancies, and less rapid change in positive expectancies. Ethnic differences in past year smoking prevalence emerged at age 14, with greater smoking prevalence among Caucasian (17%), compared to African American (8%), girls. Initial level of positive smoking expectancies and initial smoking behavior were positively associated, but positive expectancies did not predict growth in smoking behavior. Depression at age 11 was concurrently and positively associated with both positive expectancies and smoking. Study results suggest the potential utility of culturally tailored smoking prevention efforts, and the potential secondary benefit of depression treatment to prevent smoking among at-risk girls. Chung T, White H, Hipwell A, Stepp S, Loeber R. A Parallel Process Model Of The Development Of Positive Smoking Expectancies And Smoking Behavior During Early Adolescence In Caucasian And African American Girls. Addict Behav. 2010; 35(6): 647-650.
An Item Response Theory Analysis of DSM-IV Criteria for Hallucinogen Abuse and Dependence in Adolescents
This study applied both item response theory (IRT) and multiple indicators-multiple causes (MIMIC) methods to evaluate item-level psychometric properties of diagnostic questions for hallucinogen use disorders (HUDs), differential item functioning (DIF), and predictors of latent HUD. Data were drawn from 2004-2006 National Surveys on Drug Use and Health. Analyses were based on 1548 past-year hallucinogen users aged 12-17 years. Substance use and symptoms were assessed by audio computer-assisted self-interviewing methods. Analyses revealed that abuse and dependence criteria empirically were arrayed along a single continuum of severity. All abuse criteria indicated middle-to-high severity on the IRT-defined HUD continuum, while dependence criteria captured a wider range from the lowest (tolerance and time spent) to the highest (taking larger amounts and inability to cut down) severity levels. There was indication of DIF by hallucinogen users' age, gender, race/ethnicity, and ecstasy use status. Adjusting for DIF, ecstasy users (vs. non-ecstasy hallucinogen users), females (vs. males), and whites (vs. Hispanics) exhibited increased odds of HUD. The authors conclude that, empirically, symptoms of hallucinogen abuse and dependence do not reflect two discrete conditions in adolescents. Trends and problems related to hallucinogen use among girls and whites should be examined further to inform the designs of effective gender-appropriate and culturally sensitive prevention programs. Wu L, Pan J, Yang C, Reeve B, Blazer D. An Item Response Theory Analysis Of DSM-IV Criteria For Hallucinogen Abuse And Dependence In Adolescents. Addict Behav. 2010; 35(3): 273-277.
Genetic and Environmental Influences on Cannabis Use Initiation and Problematic Use: a Meta-Analysis of Twin Studies
Because cannabis use is associated with social, physical and psychological problems, it is important to know what causes some individuals to initiate cannabis use and a subset of those to become problematic users. Previous twin studies found evidence for both genetic and environmental influences on vulnerability, but due to considerable variation in the results it is difficult to draw clear conclusions regarding the relative magnitude of these influences. A systematic literature search identified 28 twin studies on cannabis use initiation and 24 studies on problematic cannabis use. The proportion of total variance accounted for by genes (A), shared environment (C) and unshared environment (E) in the initiation of cannabis use and in problematic cannabis use was calculated by averaging corresponding A, C and E estimates across studies from independent cohorts and weighting by sample size. For cannabis use initiation, A, C and E estimates were 48%, 25% and 27% in males and 40%, 39% and 21% in females. For problematic cannabis use A, C and E estimates were 51%, 20% and 29% for males and 59%, 15% and 26% for females. Confidence intervals of these estimates are considerably narrower than those in the source studies. These results suggest that vulnerability to both cannabis use initiation and problematic use is influenced significantly by genes, shared, and non-shared environmental factors, with a t trend for a greater non-shared environment and lesser genetic influence on cannabis use initiation compared to problematic use for females. Verweij K, Zietsch B, Lynskey M, Medland S, Neale M, Martin N, Boomsma D, Vink J. Genetic and Environmental Influences on Cannabis Use Initiation and Problematic Use: A Meta-Analysis Of Twin Studies. Addiction. 2010; 105(3): 417-430.
Circumstances, Pedagogy and Rationales for Injection Initiation among New Drug Injectors
Injection drug use is especially risky for new injectors. To understand the social and environmental contexts in which risks occur, researchers interviewed individuals who had initiated injection within the past 3 years (n = 146, 69.2% male) about the circumstances and rationales for their initial injection events. Respondents typically initiated injection due to tolerance (49.3%) and/or for experimentation (61.1%). Most (86.2%) did not possess the technical skills required to self-inject, and relied on the assistance of someone older (58.5%). While low levels of syringe sharing (5.8%) were reported, a majority of respondents (60.5%) engaged in at least one type of behavioral risk. Female injectors were more likely than male injectors to rely on another individual (95.5 vs. 82.2%), often a sex partner (40.5 vs. 7.2%), for assistance. The diversity seen in early injection practices highlights the need for tailored prevention messages to reach this population prior to the onset of injection risk. Goldsamt L, Harocopos A, Kobrak P, Jost J, Clatts M. Circumstances, Pedagogy And Rationales For Injection Initiation Among New Drug Injectors. J Community Health. 2010; 35(3): 258-267.
Factors Associated with Sex in the Context of Methamphetamine Use in Different Sexual Venues among HIV-positive Men who have Sex with Men
Harm reduction has focused primarily on reduction of high-risk substance using behaviors rather than reductions in high-risk sexual behaviors. Furthermore, most studies focus on individual behavior change, with less attention paid to the social and environmental context. This paper examines the interplay between the individual and social context by examining the psychosocial and behavioral characteristics of 321 methamphetamine-using HIV-positive men who have sex with men (MSM) in San Diego based on the locations or venues of their sexual activities when "high" on methamphetamine. Participants in a safer-sex intervention study underwent a baseline assessment that queried demographic and psychosocial characteristics as well as drug use and sexual risk behaviors. For purposes of analysis, respondents were classified by their preference of sexual venue: private (e.g., home), commercial (e.g., bathhouse), or public (e.g., public park or restroom). The commercial venue group was found to be younger, better educated, more likely to identify as gay, and significantly more likely to have used "club drugs" as compared to the other two groups. Men in the commercial- and public-venue groups reported more high-risk sex compared to the private-venue group. The public-venue group reported heavier drug and alcohol use, had significantly higher Beck depression scores, reported more experiences of stigma, and scored higher on a measure of sexual compulsivity than did the other two groups. In an effort to reduce HIV/STI risk-behaviors, future studies should investigate the feasibility of modifying personal, psychosocial and structural factors associated with the use of risky sexual venues where HIV-positive methamphetamine users engage in sexual activity when "high" on methamphetamine. Semple S, Strathdee S, Zians J, Patterson T. Factors Associated With Sex In The Context Of Methamphetamine Use In Different Sexual Venues Among HIV-Positive Men Who Have Sex With Men. BMC Public Health. 2010; 10: 178-184.
Barriers to Pharmacy-Based Syringe Purchase among Injection Drug Users in Tijuana, Mexico: A Mixed Methods Study
Injection drug users (IDUs) may be denied purchase of sterile syringes even where purchase without a prescription is legal. This study examined barriers to over-the-counter (OTC) syringe purchase among IDUs in Tijuana, Mexico. A quantitative survey and subsequent focus groups were used to quantify barriers to purchase, identify their correlates and provide in-depth exploration of syringe purchase experiences. Of 627 IDUs, 81% purchased a syringe in the past 6 months and 16% were refused or overcharged. Factors independently associated with refusal/overcharging were homelessness, receptive syringe sharing, >5 uses per syringe, and number of lifetime abscesses. Few pharmacies sold syringes to IDUs, who adapted by limiting purchase attempts to pharmacies known to sell syringes consistently. Failed purchases occurred when drug withdrawal required purchase at unusual times or locations, often following release from jail. IDUs reported syringe sharing, syringe reuse, and searching through unsecured medical waste for syringes in response to failed purchase attempts. Interventions to expand OTC syringe sales to IDUs, particularly near detention facilities, will facilitate safer injection practices. Pollini R, Lozada R, Gallardo M, Rosen P, Vera A, Macias A, Palinkas L, Strathdee S. Barriers To Pharmacy-Based Syringe Purchase Among Injection Drug Users In Tijuana, Mexico: A Mixed Methods Study. AIDS Behav. 2010; 14(3): 679-687.
Methamphetamine Use and Malnutrition among Street-Involved Youth
Researchers sought to explore the effect of crystal methamphetamine use on the risk of experiencing malnutrition among street-involved youth in Vancouver, Canada. Risk of malnutrition was defined as being hungry but not having enough money to buy food. Socio-demographic and drug use factors associated with risk of malnutrition were investigated using univariate and multivariate analysis among a prospective cohort of street-involved youth known as the At-Risk Youth Study (ARYS). Between September 2005 and December 2006, 509 street-involved youth were enrolled in ARYS, among whom 21% reported being at risk of malnutrition as defined above in the previous six months. In multivariate analysis, only non-injection crystal methamphetamine was significantly associated with being at risk of malnutrition among this cohort (Adjusted Odds Ratio [AOR] = 1.60, 95% Confidence Interval [CI]: 1.03 - 2.48, p = 0.036). Interventions seeking to address food insecurity among street youth may benefit from considering drug use patterns since methamphetamine use predicted higher risk in this setting. Werb D, Kerr T, Zhang R, Montaner J, Wood E. Methamphetamine Use And Malnutrition Among Street-Involved Youth. Harm Reduct J. 2010; 7: 5-9.
Evaluating Respondent-Driven Sampling in a Major Metropolitan Area: Comparing Injection Drug Users in the 2005 Seattle Area National HIV Behavioral Surveillance System Survey with Participants in the RAVEN and Kiwi Studies
Researchers sought to empirically evaluate respondent-driven sampling (RDS) recruitment methods, which have been proposed as an advantageous means of surveying hidden populations. The National HIV Behavioral Surveillance system used RDS to recruit 370 injection drug users (IDU) in the Seattle area in 2005 (NHBS-IDU1). The researchers compared NHBS-IDU1 estimates of participants' area of residence, age, race, sex, and drug most frequently injected to corresponding data from two previous surveys, the NIDA-funded RAVEN and Kiwi Studies, and to persons newly diagnosed with HIV/AIDS and reported from 2001 through 2005. They found that the NHBS-IDU1 population was more likely to reside in downtown Seattle (52%) than participants in the other 2 studies (22%-25%), be older than 50 years of age (29% vs. 5%-10%), and report multiple races (12% vs. 3%-5%). The NHBS-IDU1 population resembled persons using the downtown needle exchange in age and race distribution. An examination of cross-group recruitment frequencies in NHBS-IDU1 suggested barriers to recruitment across different areas of residence, races, and drugs most frequently injected. The substantial differences found in age and area of residence between NHBS-IDU1 and the other studies suggest that RDS may not have accessed the full universe of Seattle area injection networks. Further empirical data are needed to guide evaluations of RDS-generated samples. Burt R, Hagan H, Sabin K, Thiede H. Evaluating Respondent-Driven Sampling In A Major Metropolitan Area: Comparing Injection Drug Users In The 2005 Seattle Area National HIV Behavioral Surveillance System Survey With Participants In The RAVEN And Kiwi Studies. Ann Epidemiol. 2010; 20(2): 159-167.
Intimate Partner Violence Perpetration and Condom Use-Related Factors: Associations with Heterosexual Men 's Consistent Condom Use
Intimate partner violence victimization has been linked to sexual HIV risk behavior among heterosexual women. The unique role of perpetration of intimate partner violence (IPV) in sexual risk behavior among men has not been studied as well. Based on interviews with 518 heterosexual men recruited via street-intercept between 2005 and 2007 in New York City, the researchers assessed the relationship between perpetration of IPV against a main female partner and inconsistent condom use with that same partner, while controlling for condom use-related factors. Multivariate logistic regression revealed that men who perpetrated physical IPV were half as likely to report consistent condom use as compared with men who did not use violence, while controlling for sociodemographic, condom use-related and other factors. Physical IPV perpetration by heterosexual men makes an independent contribution to consistent condom use. Designing interventions for heterosexual men that simultaneously address both IPV and sexual risk behaviors is critical. Frye V, Panchanadeswaran S, Nandi V, Galea S, Vlahov D, Ompad D. Intimate Partner Violence Perpetration And Condom Use-Related Factors: Associations With Heterosexual Men 'S Consistent Condom Use. AIDS Behav. 2010; 50(2): 107-124.
Trajectories of Cigarette Smoking from Adolescence to Young Adulthood as Predictors of Obesity in the Mid-30s
The purpose of this longitudinal study was to examine the relationship between two major health problems, smoking and obesity, and to determine to what extent trajectories of cigarette smoking from early adolescence to young adulthood are related to obesity in the mid-30s. Participants (N = 806) were interviewed using a structured questionnaire at 6 points in time over a period of 23 years. Semiparametric group-based modeling and logistic regression analyses were used to analyze the data. The main outcome measure was obesity, assessed by body mass index in the mid-30s. Five distinct trajectories of tobacco use were identified (N = 806): heavy/continuous smokers, late starters, quitters/decreasers, occasional smokers, and nonsmokers. Compared with nonsmokers, heavy/continuous smokers or late starters had a significantly lower likelihood of obesity. Also, compared with nonsmokers or occasional smokers, heavy/continuous smokers or late starters had a significantly lower likelihood of being overweight or obese. Smoking cessation programs should focus on weight control methods, such as physical exercise and learning healthy habits. In addition, weight control programs should incorporate smoking cessation efforts as integral components. Brook D, Zhang C, Brook J, Finch S. Trajectories Of Cigarette Smoking From Adolescence To Young Adulthood As Predictors of Obesity In The Mid-30s. Nicotine Tob Res. 2010; 12(3): 263-270.
Epidemiology of HIV among Injecting and Non-injecting Drug Users: Current Trends and Implications for Interventions
Injecting drug use is a major driver of HIV infections in Eastern Europe, the Commonwealth of Independent States, North Africa, the Middle East, and many parts of Asia and North America. In this review paper, researchers provide a global overview of the epidemiology of HIV infection among drug users and present current drug use trends that may constitute important epidemic drivers. They describe trends in ethnic disparities among injecting drug using (IDU) populations in the United States, and comment upon how these trends may now be changing. They present examples where HIV infection among non-IDUs who use cocaine, crack, and methamphetamine by other routes of administration is similar to that among IDUs, and discuss potential mechanisms of HIV spread in this overlooked population. Finally, they comment upon the potential implications of these observations for HIV interventions among IDU and non-IDU populations, taking into account different strategies that are needed in settings where HIV and/or injecting drug use has been established, or threatens to emerge. Strathdee S, Stockman J. Epidemiology Of HIV Among Injecting And Non-Injecting Drug Users: Current Trends And Implications For Interventions. Curr HIV/AIDS Rep. 2010; 7(2): 99-106.
Young Adult Ecstasy Users who Forego Necessary Medical Care: a Fairly Common Occurrence with Important Health Implications
This study examined the practice of foregoing necessary medical care in a population of young adult Ecstasy users. The objectives were to (1) investigate how the failure to receive needed medical care is related to drug-related outcomes, and (2) identify factors that are associated with receiving versus foregoing needed medical care. Face-to-face, computer-assisted, structured interviews were conducted with 283 active young adult Ecstasy users in Atlanta, Georgia between August 2002 and October 2007. Study participants were recruited using a targeted sampling approach. Results indicated that almost one-third of the young adult Ecstasy users interviewed did not receive the medical care that they needed during the preceding year. Foregoing such care was associated with a variety of adverse drug-related outcomes, including experiencing a greater number of negative effects from using Ecstasy, experiencing a larger number of drug dependency symptoms, a greater likelihood of ever having binged on Ecstasy, and a greater likelihood of being classified as a "high end" polydrug abuser. Several factors were found to be associated with a greater tendency not to receive the medical care they needed, including race (not being African American), educational attainment (having completed at least high school), self-identification as belonging to the lowest socioeconomic status grouping, low self-esteem, and having experienced sexual abuse during one's formative years. Elifson K, Klein H, Sterk C. Young Adult Ecstasy Users Who Forego Necessary Medical Care: A Fairly Common Occurrence With Important Health Implications. J Psychoactive Drugs. 2010; 42(1): 63-71.
Differential Racial/Ethnic Patterns in Substance Use Initiation Among Young, Low-Income Women
Substance abuse has been associated with a host of health problems, as well as impaired social, relationship, and vocational functioning. The current study examines racial and ethnic differences in patterns of initiation of licit and illicit substance use among low-income women. A cross-sectional survey was conducted among 696 low-income women between the ages of 18 and 31 who sought gynecological care between December, 2001 and May, 2003 in southeast Texas. Overall, White women fit the classic profile of drug use initiation patterns, with those initiating tobacco and beer/wine at earlier ages being more likely to use illicit drugs. Conversely, African-American and Hispanic women initiated tobacco and beer/wine at much later ages than White women, but they were as likely to use illicit drugs. This study extends the literature by examining patterns of drug initiation among a critically underserved sample of low-income, ethnically-diverse women. Initiation of licit substance use at earlier ages was generally a risk factor for later illicit use. These findings further emphasize the importance of implementing substance use prevention programs at an early age, and focusing on the elevated risk of early initiation on later substance use disorders. Wu Z, Temple J, Shokar N, Nguyen-Oghalai T, Grady J. Differential Racial/Ethnic Patterns In Substance Use Initiation Among Young, Low-Income Women. Am J Drug Alcohol Abuse. 2010; 36(2): 123-129.