Alexandra Duncan’s research while affiliated with Johns Hopkins Bloomberg School of Public Health and other places

The Problem: The prevalence of injection drug use (IDU) and incidence of human immunodeficiency virus (HIV) remain high in Baltimore, where IDU is a primary HIV risk factor. Substance use disorders and HIV are related syndemically—their causes and consequences interact synergistically. Baltimore is increasingly considering the syndemic relationship of substance use disorders, IDU, and HIV in making decisions about drug treatment funding and location. Purpose of Article: Our goal was to empirically identify the optimal location of new drug treatment programs through the development and application of a novel, practical tool. Key Points: Syndemic triangles were constructed to measure and visualize unmet need for drug treatment services. These data were used to determine priority zones for new treatment centers. Conclusions: The application of this tool helped inform strategies for locating drug treatment services in Baltimore, and its successful use suggests its potential value in other metropolitan areas.

Risk factors for marijuana use in older adolescents and young adults have focused primarily on family environment and peer affiliation. A growing body of work has examined the relationship between environmental context and young adult substance use. This study builds on previous research linking neighborhood environment to young adult marijuana use by exploring two distinct features of neighborhoods, namely the physical (e.g., broken windows) and social environment (e.g., adults watching youth). Data were obtained from a longitudinal sample of 398 predominately African American young adults living in an urban environment. The data also included observational measures of physical and social order and disorder collected on the young adult's residential block. Exploratory structural equation modeling (ESEM) was utilized to test hypothesized relationships between these two features of the neighborhood environment and past year young adult marijuana use. A two-factor model of neighborhood environment with good fit indices was selected (CFI = 0.97, RMSEA = 0.037). There was a positive and significant direct effect from neighborhood physical disorder to marijuana use (0.219, p < 0.05) controlling for gender, race, and free and reduced price meal (FARPM) status. The direct effect from neighborhood social environment to marijuana use was not significant. These results converge with previous research linking vacant housing with young adult marijuana use but do not provide empirical support for the neighborhood social environment as a determinant of drug taking. Better explication of the social environment is needed to understand its relationship to drug use.

The current study examines differences in organizational characteristics and client posttreatment drug use abstinence in residential substance abuse treatment programs serving clients with high or low levels of legal coercion to participate in treatment. The findings show that low legal coercion programs have higher counselor caseloads (Z = 59, p < .05) than high coercion programs. Although the results showed that programs with a large proportion of African American clients (β = 14.26, p < .0001) and high legal coercion programs (β = 19.99, p < .05) predicted longer abstinence posttreatment, the final models suggest organizational factors are the key predictors of client posttreatment abstinence.

Understanding the developmental pathways and sex differences in cigarette smoking behaviors in adolescents has the potential to positively impact substance abuse prevention and to reduce smoking-related health problems. Using data from the Unplugged school-based prevention trial, we investigated different patterns of smoking behavior development among secondary school students in the Czech Republic. Growth mixture modeling was used to examine different trajectories in cigarette smoking behaviors among male and female students (N=1874 6th graders; 50.4% male, mean age 11.8 years at baseline) participating in the Unplugged school-based randomized control trial for substance use prevention. A two-class model characterized cigarette use as a function of sex and Unplugged intervention status. More rapid cigarette use increases were observed in females (OR=1.17, p=0.01 in both rapid/moderate and slow smoking escalator classes) as compared to males. Further, in both classes, more rapid increases in smoking were observed for the control group as compared to the intervention group (OR=1.22, p<0.01 slow escalators; OR=1.54, p=0.08 rapid/moderate escalators). There was no difference in sex distribution when comparing the two classes (OR=1.02, p=0.98). This study adds to a growing literature on developmental and sex differences in cigarette use among adolescents. This research supports additional multi-year prevention strategies aimed at adolescent females and early treatment programs for adolescent smokers to prevent increasing cigarette use with age.

The Czech Unplugged Study, inspired by the European Drug Addiction Prevention Trial, is a prospective, school-based, randomized controlled prevention trial designed to reduce the risk of alcohol, tobacco, inhalant, and illegal drug use in 6th graders in the Czech Republic. The intervention uses the comprehensive social influence model to affect alcohol and drug using norms among primary school students. Descriptive statistics and chi-square analyses were used to assess differences between the experimental and control groups on demographic characteristics and study outcomes. Multilevel techniques were used to take the hierarchical structure of the data into account. Prevalence odds ratios using the Bonferroni correction were calculated to assess the differences between the experimental (N = 914) and control (N = 839) groups on each outcome 1, 3, 12, 15, and 24 months after the end of the intervention. Multilevel analysis using the Bonferroni correction showed statistically significant intervention effects at the final follow-up for any smoking (OR = 0.75, 99.2% CI 0.65-0.87), daily smoking (OR = 0.62, 99.2% CI 0.48-0.79), heavy smoking (OR = 0.48, 99.2% CI 0.28-0.81), any cannabis use (OR = 0.57 99.2% CI 0.42-0.77), frequent cannabis use (OR = 0.57, 99.2% CI 0.36-0.89), and any drug use (OR = 0.78, 99.2% CI 0.65-0.94). This study adds new evidence on the effectiveness of the Unplugged school-based prevention program for primary school students in the Czech Republic.

PURPOSE: This study examined the social and contextual factors associated with continued high risk sexual behaviors among male-to-female transgender (MTFTG) adolescents living with HIV/AIDS. The study is part of a larger qualitative study of 59 racial/ethnic minority adolescents living with HIV/AIDS. METHODS: In-depth focused interviews were conducted with five MTFTG adolescents (16-24 years) living with HIV. Content analysis was conducted to identify themes related to continued sexual risk behaviors. RESULTS: Four out of five of MTFTG adolescents reported inconsistent condom use since their HIV diagnosis. Transgender stigma contributed to financial vulnerability leading to the adoption of sex work to support themselves. Sex and drugs were used to manage transgender stigma and sexual risk-taking with sex work partners was influenced by financial vulnerability. CONCLUSIONS: MTFTG adolescents with HIV have unique psychosocial needs related to transgender stigma and structural needs to decrease financial vulnerability that contribute to risky sexual behavior.

Adolescent and young adult minority women account for approximately 20% of new cases of HIV in this age group each year in the United States. It is vital to understand factors that influence sexual risk behavior in this population in order to prevent secondary transmission of HIV. As part of a larger qualitative study of youths living with HIV, in- depth interviews were conducted with 26 Black and Latina young women aged 16 to 24 years, infected with HIV through heterosexual transmission. The study explored factors related to continued unprotected sex with male partners. Since learning of their HIV infection, 23% reported multiple episodes of unprotected vaginal and/or anal sex, 27% reported condom use for some but not all of the time, 42% reported condom use all of the time and 7% were not sexually active. Among the highest risk participants partner refusal to use a condom, having the same HIV sero-status as partner, negative attitudes toward condoms, beliefs about HIV transmission, and fear of disclosure to new partners were associated with risky sex. The data suggests that more research is needed to develop more intensive interventions that address the role of gender power inequity for this sub-set of young women living with HIV.