Neighborhood socioeconomic status, personal network attributes, and use of heroin and cocaine

Race and distance effects on regular syringe exchange program use and injection risks: a geobehavioral analysis

OBJECTIVES

We conducted "geobehavioral" analyses by race to understand how distances among injection drug users' (IDUs') residences, drug purchase and use locations, and syringe exchange programs (SEPs) are associated with injection behaviors.

METHODS

Data were from the HIV Prevention Trial Network 037 (2002-2006) site in Philadelphia, Pennsylvania, a randomized study evaluating the efficacy of a network-oriented HIV prevention intervention for IDUs. At prescreening, participants were asked the nearest intersections to their residence, where they buy and use drugs, and about their injection behaviors.

RESULTS

Geographic distances had independent and interactive effects on injection risk behaviors and SEP use. Blacks, regardless of distance, were less likely than Whites to inject in public places (odds ratio [OR] = 0.62; 95% confidence interval [CI] = 0.43, 0.90), to use syringes after someone else (OR = 0.27; 95% CI = 0.19, 0.38), and to access syringes from SEPs (OR = 2.08; 95% CI = 1.48, 2.92). Latinos' injection behaviors were more distance-dependent than Blacks' or Whites'.

CONCLUSIONS

Distances among IDUs' homes, drug purchase and injecting sites, and prevention resources affected safe injection practices differentially by race. Understanding individuals' geographic relation to the risks and resources that surround them is an important aspect of understanding effects of the environment on health and behavior and the development of targeted interventions.

Discrimination-related stress, blood pressure and epstein-barr virus antibodies among latin american immigrants in Oregon, us

Perceived discrimination has been linked to poor health outcomes among ethnic and racial minorities in the United States, though the relationship of discrimination-related stress to immigrant health is not well understood. This article reports findings from a preliminary study that examined blood pressure and Epstein-Barr virus antibody levels in relation to self-reported indicators of stress, acculturation and social support among 79 adult immigrant Latino farm workers in Oregon, US. Findings show that increases in discrimination-related stress predicted elevated systolic blood pressure (SBP) and Epstein-Barr virus antibody levels among male participants. Though female participants reported similar levels of discrimination stress, this perceived stress was not reflected in biological measures. Among women, greater English language engagement was linked to higher SBP, and more years in the US was associated with higher diastolic blood pressure. Study results suggest that male and female immigrants' physiological responses to stress may be influenced in distinctive ways by processes of adjustment to life in the US. If replicated, the finding that discrimination stress predicts elevated SBP may have clinical and public health implications given that elevated SBP is an established risk factor for cardiovascular disease.

Drug problems among homeless individuals in Toronto, Canada: prevalence, drugs of choice, and relation to health status

BACKGROUND

Drug use is believed to be an important factor contributing to the poor health and increased mortality risk that has been widely observed among homeless individuals. The objective of this study was to determine the prevalence and characteristics of drug use among a representative sample of homeless individuals and to examine the association between drug problems and physical and mental health status.

METHODS

Recruitment of 603 single men, 304 single women, and 284 adults with dependent children occurred at homeless shelters and meal programs in Toronto, Canada. Information was collected on demographic characteristics and patterns of drug use. The Addiction Severity Index was used to assess whether participants suffered from drug problems. Associations of drug problems with physical and mental health status (measured by the SF-12 scale) were examined using regression analyses.

RESULTS

Forty percent of the study sample had drug problems in the last 30 days. These individuals were more likely to be single men and less educated than those without drug problems. They were also more likely to have become homeless at a younger age (mean 24.8 vs. 30.9 years) and for a longer duration (mean 4.8 vs. 2.9 years). Marijuana and cocaine were the most frequently used drugs in the past two years (40% and 27%, respectively). Drug problems within the last 30 days were associated with significantly poorer mental health status (-4.9 points, 95% CI -6.5 to -3.2) but not with poorer physical health status (-0.03 points, 95% CI -1.3 to 1.3)).

CONCLUSIONS

Drug use is common among homeless individuals in Toronto. Current drug problems are associated with poorer mental health status but not with poorer physical health status.

Neighborhood poverty and injection cessation in a sample of injection drug users

Neighborhood socioeconomic environment may be a determinant of injection drug use cessation. The authors used data from a prospective cohort study of Baltimore City, Maryland, injection drug users assessed between 1990 and 2006. The study examined the relation between living in a poorer neighborhood and the probability of injection cessation among active injectors, independent of individual characteristics and while respecting the temporality of potential confounders, exposure, and outcome. Participants' residences were geocoded, and the crude, adjusted, and inverse probability of exposure weighted associations between neighborhood poverty and injection drug use cessation were estimated. Weighted models showed a strong association between neighborhood poverty and injection drug use cessation; living in a neighborhood with fewer than 10%, compared with more than 30%, of residents in poverty was associated with a 44% increased odds of not injecting in the prior 6 months (odds ratio = 1.44, 95% confidence interval: 1.14, 1.82). Results show that neighborhood environment may be an important determinant of drug injection behavior independent of individual-level characteristics.

The social context of homeless women's alcohol and drug use

BACKGROUND

Substance use poses a significant threat to the health of women, and homeless women are more likely to use alcohol and drugs than other women. Addressing risk factors in this population requires a focus on the social context of substance use among homeless women.

METHODS

Participants were 445 homeless women who were randomly sampled and interviewed in shelter settings about the characteristics of their personal networks. Binomial logistic regressions predicted days of binge drinking and of using marijuana, crack, cocaine, and methamphetamine or other amphetamines in the past 6 months.

RESULTS

Homeless women with a greater proportion of heavy alcohol users in their personal networks had greater odds of engaging in binge drinking, and women with a greater proportion of drug users in their networks had greater odds of using marijuana, cocaine, crack, and methamphetamine or other amphetamines. Women with a greater proportion of individuals in their networks that they had met in school or through work had lower odds of marijuana, cocaine, and crack use.

CONCLUSIONS

Findings suggest the importance of structural solutions in addressing homeless women's alcohol and drug use, including greater access to treatment and recovery support for alcohol and drug problems as well as depression, and enhancing employment and educational opportunities for homeless women.

Association of substance use disorders with childhood trauma but not African genetic heritage in an African American cohort

OBJECTIVE

Genetic variation influences differential vulnerability to addiction within populations. However, it remains unclear whether differences in frequencies of vulnerability alleles contribute to disparities between populations and to what extent ancestry correlates with differential exposure to environmental risk factors, including poverty and trauma.

METHOD

The authors used 186 ancestry-informative markers to measure African ancestry in 407 addicts and 457 comparison subjects self-identified as African Americans. The reference group was 1,051 individuals from the Human Genome Diversity Cell Line Panel, which includes 51 diverse populations representing most worldwide genetic diversity.

RESULTS

African Americans varied in degrees of African, European, Middle Eastern, and Central Asian genetic heritage. The overall level of African ancestry was actually smaller among cocaine, opiate, and alcohol addicts (proportion=0.76-0.78) than nonaddicted African American comparison subjects (proportion=0.81). African ancestry was associated with living in impoverished neighborhoods, a factor previously associated with risk. There was no association between African ancestry and exposure to childhood abuse or neglect, a factor that strongly predicted all types of addictions.

CONCLUSIONS

These results suggest that African genetic heritage does not increase the likelihood of genetic risk for addictions. They highlight the complex interrelation between genetic ancestry and social, economic, and environmental conditions and the strong relation of those factors to addiction. Studies of epidemiological samples characterized for genetic ancestry and social, psychological, demographic, economic, cultural, and historical factors are needed to better disentangle the effects of genetic and environmental factors underlying interpopulation differences in vulnerability to addiction and other health disparities.

A social network perspective on heroin and cocaine use among adults: evidence of bidirectional influences

AIMS

While several studies have documented a relationship between initiation of drug use and social network drug use in youth, the direction of this association is not well understood, particularly among adults or for stages of drug involvement beyond initiation. The present study sought to examine two competing theories (social selection and social influence) in the longitudinal relationship between drug use (heroin and/or cocaine) and social network drug use among drug-experienced adults.

DESIGN

Three waves of data came from a cohort of 1108 adults reporting a life-time history of heroin and/or cocaine use.

SETTING

Low-income neighborhoods with high rates of drug use in Baltimore, Maryland.

PARTICIPANTS

Participants had weekly contact with drug users and were 18 years of age or older.

MEASUREMENTS

Drug use data were self-report. Network drug use was assessed through a social network inventory. Close friends were individuals whom the participant reported seeing daily or rated as having the highest level of trust. Findings Structural equation modeling indicated significant bidirectional influences. The majority of change in network drug use over time was due to change in the composition of the network rather than change in friends' behavior. Drug use by close peers did not influence participant drug use beyond the total network.

CONCLUSIONS

There is evidence of both social selection and social influence processes in the association between drug use and network drug use among drug-experienced adults.

Area-level socioeconomic status in relation to outcomes in gamma-hydroxybutyrate intoxication

BACKGROUND

Area-level socioeconomic status (SES) may play an important role in drug abuse patterns, including related health outcomes. This may be particularly relevant for gamma-hydroxybutyrate (GHB), which is prototypical of "party" drug abuse.

METHODS

We retrospectively reviewed GHB-related cases reported to the California Poison Control System (CPCS; January 1, 1999 through June 30, 2007). We limited analysis to CPCS calls containing a residential zip code (ZC). The CPCS data were extracted for key case characteristics, including the residential ZC. We linked cases to corresponding 2000 U.S. Census data for area-level measures of SES and demographics. We used multiple logistic regression analysis to test the associations between area-level SES and GHB case severity, taking into account area-level demographics and individual-level GHB high-risk behaviors.

RESULTS

We analyzed 210 cases. Taking into account area-level demographics (age and racial mix; urbanicity) and GHB-related high-risk behaviors (use of GHB congeners; GHB-dependence; co-ingestion of other agents), we associated higher area-level SES with greater GHB case severity. There was 40% increased likelihood of major GHB adverse health outcomes for every $100,000 incremental increase in median home values (OR 1.41; 95% CI 1.1-1.8). For median annual household income (per $10,000), the association was similar (OR 1.39; 95% CI 1.0-1.9).

CONCLUSION

Higher area-level SES is associated with greater GHB-related case severity. This study may serve as a model using a geographic information system (GIS) approach to study the population-based correlates of drugs of abuse reported through poison control surveillance.

Risk environments and drug harms: a social science for harm reduction approach

A 'risk environment' framework promotes an understanding of harm, and harm reduction, as a matter of 'contingent causation'. Harm is contingent upon social context, comprising interactions between individuals and environments. There is a momentum of interest in understanding how the relations between individuals and environments impact on the production and reduction of drug harms, and this is reflected by broader debates in the social epidemiology, political economy, and sociology of health. This essay maps some of these developments, and a number of challenges. These include: social epidemiological approaches seeking to capture the socially constructed and dynamic nature of individual-environment interactions; political-economic approaches giving sufficient attention to how risk is situated differentially in local contexts, and to the role of agency and experience; understanding how public health as well as harm reduction discourses act as sites of 'governmentality' in risk subjectivity; and focusing on the logics of everyday habits and practices as a means to understanding how structural risk environments are incorporated into experience. Overall, the challenge is to generate empirical and theoretical work which encompasses both 'determined' and 'productive' relations of risk across social structures and everyday practices. A risk environment approach brings together multiple resources and methods in social science, and helps frame a 'social science for harm reduction'.

Social epidemiology and complex system dynamic modelling as applied to health behaviour and drug use research

A social epidemiologic perspective considers factors at multiple levels of influence (e.g., social networks, neighbourhoods, states) that may individually or jointly affect health and health behaviour. This provides a useful lens through which to understand the production of health behaviours in general, and drug use in particular. However, the analytic models that are commonly applied in population health sciences limit the inference we are able to draw about the determination of health behaviour by factors, likely interrelated, across levels of influence. Complex system dynamic modelling techniques may be useful in enabling the adoption of a social epidemiologic approach in health behaviour and drug use research. We provide an example of a model that aims to incorporate factors at multiple levels of influence in understanding drug dependence. We conclude with suggestions about future directions in the field and how such models may serve as virtual laboratories for policy experiments aimed at improving health behaviour.