Faculty Bibliography

OBJECTIVES: We sought to determine whether contextual factors shape injection drug use among Black adolescents and adults. METHODS: For this longitudinal study of 95 US metropolitan statistical areas (MSAs), we drew annual MSA-specific estimates of the prevalence of injection drug use (IDU) among Black adolescents and adults in 1993 through 2007 from 3 surveillance databases. We used existing administrative data to measure MSA-level socioeconomic status; criminal justice activities; expenditures on social welfare, health, and policing; and histories of Black uprisings (1960-1969) and urban renewal funding (1949-1974). We regressed Black IDU prevalence on these predictors by using hierarchical linear models. RESULTS: Black IDU prevalence was lower in MSAs with declining Black high-school dropout rates, a history of Black uprisings, higher percentages of Black residents, and, in MSAs where 1992 White income was high, higher 1992 Black income. Incarceration rates were unrelated. CONCLUSIONS: Contextual factors shape patterns of drug use among Black individuals. Structural interventions, especially those that improve Black socioeconomic security and political strength, may help reduce IDU among Black adolescents and adults.

There is considerable interest in the effects of medical marijuana laws (MML) on marijuana use in the USA, particularly among youth. The article by Stolzenberg et al. (2015) "The effect of medical cannabis laws on juvenile cannabis use" concludes that "implementation of medical cannabis laws increase juvenile cannabis use". This result is opposite to the findings of other studies that analysed the same US National Survey on Drug Use in Households data as well as opposite to studies analysing other national data which show no increase or even a decrease in youth marijuana use after the passage of MML. We provide a replication of the Stolzenberg et al. results and demonstrate how the comparison they are making is actually driven by differences between states with and without MML rather than being driven by pre and post-MML changes within states. We show that Stolzenberg et al. do not properly control for the fact that states that pass MML during 2002-2011 tend to already have higher past-month marijuana use before passing the MML in the first place. We further show that when within-state changes are properly considered and pre-MML prevalence is properly controlled, there is no evidence of a differential increase in past-month marijuana use in youth that can be attributed to state MML.

Population distributions of health emerge from the complex interplay of health-related factors at multiple levels, from the biological to the societal level. Individuals are aggregated within social networks, affected by their locations, and influenced differently across time. From aggregations of individuals, group properties can emerge, including some exposures that are ubiquitous within populations but variant across populations. By combining a focus on social determinants of health with a conceptual framework for understanding how genetics, biology, behavior, psychology, society, and environment interact, a systems science approach can inform our understanding of the underlying causes of the unequal distribution of health across generations and populations, and can help us identify promising approaches to reduce such inequalities. In this paper, we discuss how systems science approaches have already made several substantive and methodological contributions to the study of population health from a social epidemiology perspective.

BACKGROUND:To our knowledge, there are no universal screening tools for substance dependence that (1) were developed using a population-based sample, (2) estimate total risk briefly and inexpensively by incorporating a relatively small number of well-established risk factors, and (3) aggregate risk factors using a simple algorithm. We created a universal screening tool that incorporates these features to identify adolescents at risk for persistent substance dependence in adulthood. METHOD/METHODS:Participants were members of a representative cohort of 1037 individuals born in Dunedin, New Zealand in 1972-1973 and followed prospectively to age 38 years, with 95% retention. We assessed a small set of childhood and adolescent risk factors: family history of substance dependence, childhood psychopathology (conduct disorder, depression), early exposure to substances, frequent substance use in adolescence, sex, and childhood socioeconomic status. We defined the outcome (persistent substance dependence in adulthood) as dependence on one or more of alcohol, tobacco, cannabis, or hard drugs at ⩾3 assessment ages: 21, 26, 32, and 38 years. RESULTS:A cumulative risk index, a simple sum of nine childhood and adolescent risk factors, predicted persistent substance dependence in adulthood with considerable accuracy (AUC = 0.80). CONCLUSIONS:A cumulative risk score can accurately predict which adolescents in the general population will develop persistent substance dependence in adulthood.

Black men who have sex with men (BMSM) are highest risk for HIV seroconversion in the United States. Little attention has been paid to marijuana use among BMSM and potential for HIV risk. A sample of 202 BMSM was generated through respondent driven sampling. The relationship between differential marijuana use and both HIV risk behavior and social network factors were examined using weighted logistic regression. Of the BMSM in this sample 60.4 % use marijuana in general and 20.8 % use marijuana as sex-drug. General marijuana use was significantly associated with participation in group sex (AOR 3.50; 95 % CI 1.10-11.10) while marijuana use as a sex drug was significantly associated with both participation in condomless sex (AOR 2.86; 95% CI 1.07-7.67) and group sex (AOR 3.39; 95% CI 1.03-11.22). Respondents with a moderate or high perception of network members who use marijuana were more likely to use marijuana both in general and as a sex-drug. Network member marijuana use, while not associated with risk behaviors, is associated with individual marijuana use and individual marijuana use in the context of sex is associated with risk practices. Targeting interventions towards individuals and their respective networks that use marijuana as a sex drug may reduce HIV risk.

BACKGROUND:Heroin production in Colombia has increased dramatically in recent decades, and some studies point to an increase in local heroin use since the mid-1990s. Despite this rapid increase, little is known about the effects of these activities on heroin injection within Colombia. One of the biggest concerns surrounding heroin injection is the potential spread of HIV through drug user networks. OBJECTIVES/OBJECTIVE:This article examines injection risk behaviors among heroin injectors in the Colombian cities of Medellín and Pereira to explore the implications for possible increased HIV transmission within this group. METHODS:A cross-sectional study used respondent-driving sampling to recruit a sample of 540 people who inject drugs (PWID) over 18 years of age (Medellín: n = 242, Pereira: n = 298). Structured interviews with each participant were conducted using the World Health Organization Drug Injection Study Phase II Survey. An HIV test was also administered. RESULTS:Information regarding the socio-demographics, injection drug use, HIV risk and transmission behaviors, injection risk management, and HIV knowledge and prevalence of participants are reported. The study identified many young, newly initiated injectors who engage in risky injection practices. The study also found that HIV prevalence is fairly low among participants (2.7%). CONCLUSIONS/IMPORTANCE/CONCLUSIONS:Findings indicate a potential risk for the spread of HIV among PWID in Colombia given their widespread sharing practices, high rate of new injector initiation, and unsafe syringe cleaning practices. Colombia has a possibly time-limited opportunity to prevent an HIV epidemic by implementing harm reduction interventions among young, newly initiated PWID.

The United States HIV epidemic disproportionately affects Black and Hispanic men who have sex with men (MSM). This disparity might be partially explained by differences in social and sexual network structure and composition. A total of 1267 MSM in New York City completed an ACASI survey and egocentric social and sexual network inventory about their sex partners in the past 3 months, and underwent HIV testing. Social and sexual network structure and composition were compared by race/ethnicity of the egos: black, non-Hispanic (N = 365 egos), white, non-Hispanic (N = 466), and Hispanic (N = 436). 21.1% were HIV-positive by HIV testing; 17.2% reported serodiscordant and serostatus unknown unprotected anal/vaginal intercourse (SDUI) in the last 3 months. Black MSM were more likely than white and Hispanic MSM to report exclusively having partners of same race/ethnicity. Black and Hispanic MSM had more HIV-positive and unknown status partners than white MSM. White men were more likely to report overlap of social and sex partners than black and Hispanic men. No significant differences by race/ethnicity were found for network size, density, having concurrent partners, or having partners with >/=10 years age difference. Specific network composition characteristics may explain racial/ethnic disparities in HIV infection rates among MSM, including HIV status of sex partners in networks and lack of social support within sexual networks. Network structural characteristics such as size and density do not appear to have such an impact. These data add to our understanding of the complexity of social factors affecting black MSM and Hispanic MSM in the U.S.

BACKGROUND/OBJECTIVES: physical activity may be beneficial in reducing depression incidence among the elderly. A key unanswered question is whether certain types of physical activity are particularly associated with decreased depression incidence. We examined the relationship between quantity and type of physical activity and subsequent depression using longitudinal data from elderly adults in New York City (NYC). METHODS: we followed 3,497 adults aged 65-75 living in NYC for three years. Total physical activity was measured using the Physical Activity Scale for the Elderly (PASE) and type of physical activity was measured using a latent class analysis of PASE item responses. We used generalised estimating equations to measure the relationship between quantity and latent class of physical activity at waves 1-2 and depression at waves 2-3, controlling for wave-1 depression. RESULTS: individuals in the second highest quartile (50-75%) (odds ratio (OR) = 0.45; 95% confidence interval (CI) = 0.23, 0.88) and highest quartile of activity (OR = 0.31; 95% CI = 0.16, 0.63) had lower odds of depression. Among all subjects, athletic types (OR = 0.25; 95% CI = 0.12, 0.51) and walker types (OR = 0.58; 95% CI = 0.34, 0.99) had lower odds of depression. Among non-disabled participants, walkers (OR = 0.36; 95% CI = 0.18, 0.73), athletic types (OR = 0.14; 95% CI = 0.06, 0.32), domestic/gardening types (OR = 0.29; 95% CI = 0.12, 0.73) and domestic/gardening athletic types (OR = 0.13; 95% CI = 0.02, 0.75) had lower odds of depression. CONCLUSION: respondents who practised the highest levels of physical activity and who performed athletic activities were at lower risk for depression. Interventions aimed at promoting athletic physical activity among older adults may generate benefits for mental health.