Activity spaces among injection drug users in San Francisco

Social-spatial network structures among young urban and suburban persons who inject drugs in a large metropolitan area

BACKGROUND

Recent studies underscore the significance of adopting a syndemics approach to study opioid misuse, overdose, hepatitis C (HCV) and HIV infections, within the broader context of social and environmental contexts in already marginalized communities. Social interactions and spatial contexts are crucial structural factors that remain relatively underexplored. This study examines the intersections of social interactions and spatial contexts around injection drug use. More specifically, we investigate the experiences of different residential groups among young (aged 18-30) people who inject drugs (PWID) regarding their social interactions, travel behaviors, and locations connected to their risk behaviors. By doing so, we aim to achieve a more comprehensive understanding of the multidimensional risk environment, thereby facilitating the development of informed policies.

METHODS

We collected and examined data regarding young PWID's egocentric injection network and geographic activity spaces (i.e., where they reside, inject drugs, purchase drugs, and meet sex partners). Participants were stratified based on the location of all place(s) of residence in the past year i.e., urban, suburban, and transient (both urban and suburban) to i) elucidate geospatial concentration of risk activities within multidimensional risk environments based on kernel density estimates; and ii) examine spatialized social networks for each residential group.

RESULTS

Participants were mostly non-Hispanic white (59%); 42% were urban residents, 28% suburban, and 30% transient. We identified a spatial area with concentrated risky activities for each residential group on the West side of Chicago in Illinois where a large outdoor drug market area is located. The urban group (80%) reported a smaller concentrated area (14 census tracts) compared to the transient (93%) and suburban (91%) with 30 and 51 tracts, respectively. Compared to other areas in Chicago, the identified area had significantly higher neighborhood disadvantages. Significant differences were observed in social network structures and travel behaviors: suburban participants had the most homogenous network in terms of age and residence, transient participants had the largest network (degree) and more non-redundant connections, while the urban group had the shortest travel distance for all types of risk activities.

CONCLUSION

Distinct residential groups exhibit varying patterns of network interaction, travel behaviors, and geographical contexts related to their risk behaviors. Nonetheless, these groups share common concentrated risk activity spaces in a large outdoor urban drug market area, underscoring the significance of accounting for risk spaces and social networks in addressing syndemics within PWID populations.

A Novel Index Measure of Housing-related Risk as a Predictor of Overdose among Young People Who Inject Drugs and Injection Networks

Background

For people who inject drugs (PWID), housing instability due to decreasing housing affordability and other factors (e.g., loss of housing due to severed relational ties, evictions due to drug use) results in added pressure on an already vulnerable population. Research has shown that housing instability is associated with overdose risk among PWID. However, the construct of housing instability has often been operationalized as a single dimension (e.g., housing type, homelessness, transience). We propose a multi-dimensional measure of housing instability risk and examine its association with drug overdose to promote a more holistic examination of housing status as a predictor of overdose.

Methods

The baseline data from a network-based, longitudinal study of young PWID and their networks living in metropolitan Chicago, Illinois was analyzed to examine the relationship between a housing instability risk index-consisting of five dichotomous variables assessing housing instability-and lifetime overdose count using negative binomial regression.

Results

We found a significant positive association between the housing instability risk score and lifetime overdose count after adjusting for 12 variables.

Conclusions

Our results support the practical utility of a multi-dimensional measure of housing instability risk in predicting overdose and highlight the importance of taking a holistic approach to addressing housing instability when designing interventions.

Social-spatial network structures among young urban and suburban persons who inject drugs in a large metropolitan area

Background

It is estimated that there are 1.5% US adult population who inject drugs in 2018, with young adults aged 18-39 showing the highest prevalence. PWID are at a high risk of many blood-borne infections. Recent studies have highlight the importance of employing the syndemic approach to study opioid misuse, overdose, HCV and HIV, along with the social and environmental contexts where these interrelated epidemics occur in already marginalized communities. Social interactions and spatial contexts are important structural factors that are understudied.

Methods

Egocentric injection network and geographic activity spaces for young (aged 18-30) PWID and their injection, sexual, and social support network members (i.e., where reside, inject drugs, purchase drugs, and meet sex partners) were examined using baseline data from an ongoing longitudinal study (n=258). Participants were stratified based on the location of all place(s) of residence in the past year i.e., urban, suburban, and transient (both urban and suburban) to i) elucidate geospatial concentration of risk activities within multi-dimensional risk environments based on kernel density estimates; and ii) examine spatialized social networks for each residential group.

Results

Participants were mostly non-Hispanic white (59%); 42% were urban residents, 28% suburban, and 30% transient. We identified a spatial area with concentrated risky activities for each residence group on the West side of Chicago where a large outdoor drug market area is located. The urban group (80%) reported a smaller concentrated area (14 census tracts) compared to the transient (93%) and suburban (91%) with 30 and 51 tracts, respectively. Compared to other areas in Chicago, the identified area had significantly higher neighborhood disadvantages (e.g., higher poverty rate, p <0.001). Significant ( p <0.01 for all) differences were observed in social network structures: suburban had the most homogenous network in terms of age and residence, transient participants had the largest network (degree) and more non-redundant connections.

Conclusion

We identified concentrated risk activity spaces among PWID from urban, suburban, and transient groups in a large outdoor urban drug market area, which highlights the need for considering the role of risk spaces and social networks in addressing the syndemics in PWID populations.

A qualitative exploration of daily path and daily routine among people in Ukraine who inject drugs to understand associated harms

Background

Patterns of movement, heterogeneity of context, and individual space-time patterns affect health, and individuals’ movement throughout the landscape is shaped by addiction, meeting basic needs, and maintaining relationships. Place and social context enable or constrain behavior and individuals use social networks and daily routines to accomplish individual goals and access resources.

Methods

This article explores drug use as part of daily routines and daily paths among people who inject drugs in Dnipro City, Ukraine. Between March and August 2018, we interviewed 30 people who inject drugs living in Dnipro City, Ukraine. Study participants completed a single interview that lasted between 1 and 2 hours. During the interview, participants described their daily routine and daily path using a printed map of Dnipro as a prompt. Participants were asked to draw important sites; give time estimates of arrival and departure; and annotate on the map the points, paths, and areas most prominent or important to them. Participants also described to what extent their daily routines were planned or spontaneous, how much their daily path varied over time, and how drug use shaped their daily routine.

Results

We identified 3 major types of daily routine: unpredictable, predictable, and somewhat predictable. Participants with unpredictable daily routines had unreliable sources of income, inconsistent drug suppliers and drug use site, and dynamic groups of people with whom they socialized and used drugs. Participants with predictable daily routines had reliable sources of income, a regular drug dealer or stash source, and a stable group of friends or acquaintances with whom they bought and/or used drugs. Participants with somewhat predictable daily routines had some stable aspects of their daily lives, such as a steady source of income or a small group of friends with whom they used drugs, but also experienced circumstances that undermined their ability to have a routinized daily life, such as changing drug use sites or inconsistent income sources.

Conclusions

Greater attention needs to be paid to the daily routines of people who use drugs to develop and tailor interventions that address the place-based and social contexts that contribute to drug-use related risks.

Is social-ecological risk associated with individual HIV risk beliefs and behaviours?: An analysis of Kenyan adolescents' local communities and activity spaces

The places where adolescents live, learn, and play are thought to influence behaviours and health, but we have limited tools for measuring environmental risk on a hyperlocal (e.g. neighbourhood) level. Working with 218 adolescents and their parents/guardians in rural western Kenya, we combined participatory mapping activities with satellite imagery to identify adolescent activity spaces and create a novel measure of social-ecological risks. We then examined the associations between social-ecological risk and individual HIV risk beliefs and behaviours. We found support for the conjecture that social-ecological risks may be associated with individual beliefs and behaviours. As social-ecological risk increased for a sample of Kenyan adolescents, so did their reports of riskier sex beliefs and behaviours, as well as unsupervised outings at night. This study reinforces calls for disease prevention approaches that go beyond emphasising individual behaviour change.

City streetscapes and neighborhood characteristics of fatal opioid overdoses among people experiencing homelessness who use drugs in New York City, 2017-2019

BACKGROUND

While housing is a critical social determinant of nonprescription opioid overdose, little is known about how place impacts fatal overdose for people experiencing homelessness (PEH) who use drugs beyond the public versus private domains. This study investigated patterns of neighborhood environment features at locations of fatal overdoses among PEH.

METHODS

We remotely visited locations of opioid-involved fatal overdoses provided by the New York City Office of the Chief Medical Examiner, 2017-2019 (n=3276), with Google Street View and used systematic social observation to assess characteristics of the street block related to drug exposures. We cross-referenced home address with city shelters and supportive housing to identify PEH (n=503). We used the differences of K functions from the spatial point patterns and kernel ratio function maps to identify geographic clusters. We then used logistic regression to identify significant individual-, block-, and neighborhood-level covariates (neighborhood deprivation, segregation, population density).

RESULTS

Over half (55.9%, n=281) of fatal overdoses among PEH occurred in supportive housing or shelters, and 15.5% (n=78) occurred in public spaces (e.g., parks). Spatial analyses identified areas of significant concentrated fatal overdoses among PEH in Manhattan, the South Bronx, and Brooklyn. We identified several significant indicators of physical and social order and disorder associated with increased odds of experiencing homelessness at time of fatal overdose, including construction/renovation, graffiti, traffic calming features, and loitering.

CONCLUSION

Harm reduction services should be co-located in facilities that serve PEH and targeted to street blocks with indicators of physical and social disorder. While supportive housing is a crucial step in preventing fatal opioid overdoses among PEH, identifying neighborhoods for intervention services delivery and harm reduction outreach for PEH is necessary.

Relationships between places of residence, injury, and death: Spatial and statistical analysis of fatal opioid overdoses across Massachusetts

Understanding the factors associated with where people who use opioids live, where their fatal overdoses occur, and where deaths are recorded can improve our knowledge of local risk environments and inform intervention planning. Through geospatial analyses of death certificate data between 2015 and 2017, we found that a majority of opioid-involved fatal overdoses in Massachusetts occurred at home. Age (adjusted odds ratio [AOR], 1.03; 95% confidence interval [CI], 1.02-1.04), living in a census tract with a higher percentage of crowded households (AOR, 1.04; 95% CI, 1.01-1.08), households without vehicles (AOR, 1.01; 95% CI, 1.00-1.02), and Hispanic ethnicity (AOR, 0.56; 95% CI, 0.42-0.74) were independently associated with fatal overdose at home. Using geographically weighted regression, we identified locations where these associations were stronger and could benefit most from home-based and culturally sensitive overdose prevention efforts, including expanded overdose education and naloxone distribution.

Conceptualizing the Socio-Built Environment: An Expanded Theoretical Framework to Promote a Better Understanding of Risk for Nonmedical Opioid Overdose Outcomes in Urban and Non-Urban Settings

Nonmedical opioid (NMO) use has been linked to significant increases in rates of NMO morbidity and mortality in non-urban areas. While there has been a great deal of empirical evidence suggesting that physical features of built environments represent strong predictors of drug use and mental health outcomes in urban settings, there is a dearth of research assessing the physical, built environment features of non-urban settings in order to predict risk for NMO overdose outcomes. Likewise, there is strong extant literature suggesting that social characteristics of environments also predict NMO overdoses and other NMO use outcomes, but limited research that considers the combined effects of both physical and social characteristics of environments on NMO outcomes. As a result, important gaps in the scientific literature currently limit our understanding of how both physical and social features of environments shape risk for NMO overdose in rural and suburban settings and therefore limit our ability to intervene effectively. In order to foster a more holistic understanding of environmental features predicting the emerging epidemic of NMO overdose, this article presents a novel, expanded theoretical framework that conceptualizes "socio-built environments" as comprised of (a) environmental characteristics that are applicable to both non-urban and urban settings and (b) not only traditional features of environments as conceptualized by the extant built environment framework, but also social features of environments. This novel framework can help improve our ability to identify settings at highest risk for high rates of NMO overdose, in order to improve resource allocation, targeting, and implementation for interventions such as opioid treatment services, mental health services, and care and harm reduction services for people who use drugs.

An Exploration of Narcan as a Harm Reduction Strategy and User's Attitudes toward Law Enforcement Involvement in Overdose Cases

The street homeless, those who spend their nights either in shelters or unofficial camps, whether in tents on a street or in society’s hidden spaces such as beneath an overpass, face multiple challenges beyond finding a safe place to sleep. Of further concern is how official actions can worsen these situations, through day-to-day activities or planned intervention strategies. In this paper we explore how a planned intervention may be negatively perceived—even as a form of “structural violence”—and may prevent Narcan (naloxone) use to stop an overdose related death in the Skid Row of Los Angeles. Data for this study consisted of a combination of Spatial Video Geonarratives (SVGs) and 325 incident reports from the Homeless Health Care Los Angeles Center for Harm Reduction (HHCLA-HRC) between November 2014 and December 2015. Chi-square and simple logistic regression models were used to examine the association between fear-of-arrest and other covariates of interest. Mapping results are presented with different sets of shapefiles created for (1) all Narcan uses, (2) all homeless, (3) all homeless with a worry about being arrested, (4) all Narcan uses where an ambulance attended, (5) and the same as 4 but also with police attendance. In the multivariable model, the estimated adjusted odds of fear-of-arrest is over three times higher among Narcan users ages 30–39 when compared to users under the age of 30. Analyzing the association of calling 9-1-1 on Narcan user demographics, socio-contextual characteristics, and overdose victim demographics, the crude estimated probability of calling 9-1-1 for Narcan users aged 50 and older is nearly three times higher when compared to Narcan users aged 19–29. Conclusion: Results suggest that the fear-of-arrest and calling 9-1-1 during an overdose is still a concern among Narcan users despite protective legislation and access to harm reduction resources.

A Systematic Review of Neighborhood-Level Influences on HIV Vulnerability

A better understanding of the social-structural factors that influence HIV vulnerability is crucial to achieve the goal of ending the HIV epidemic by 2030. Given the role of neighborhoods in HIV outcomes, synthesis of findings from such research is key to inform efforts toward HIV eradication. We conducted a systematic review to examine the relationship between neighborhood-level factors (e.g., poverty) and HIV vulnerability (via sexual behaviors and substance use). We searched six electronic databases for studies published from January 1, 2007 through November 30, 2017 (PROSPERO CRD42018084384). We also mapped the studies' geographic distribution to determine whether they aligned with high HIV prevalence areas and/or the "Ending the HIV Epidemic: A Plan for the United States". Fifty-five articles met inclusion criteria. Neighborhood disadvantage, whether measured objectively or subjectively, is one of the most robust correlates of HIV vulnerability. Tests of associations more consistently documented a relationship between neighborhood-level factors and drug use than sexual risk behaviors. There was limited geographic distribution of the studies, with a paucity of research in several counties and states where HIV incidence/prevalence is a concern. Neighborhood influences on HIV vulnerability are the consequence of centuries-old laws, policies and practices that maintain racialized inequities (e.g., racial residential segregation, inequitable urban housing policies). We will not eradicate HIV without multi-level, neighborhood-based approaches to undo these injustices. Our findings inform future research, interventions and policies.

Examining the spatial risk environment tied to the opioid crisis through a unique public health, EMS, and academic research collaborative: Lowell, Massachusetts, 2008–2018

Between 2015 and 2018, Lowell Massachusetts experienced outbreaks in opioid overdoses, HIV, and hepatitis C virus infections (HCV) among people who inject drugs. Through an innovative collaboration between emergency medical services (EMS), public health, and academic partners, we assessed the geographic distribution of opioid-related risks to inform intervention efforts. We analyzed data from three unique data sources for publicly discarded syringes, opioid-related incidents (ORIs), and fatal opioid overdoses in Lowell between 2008 and 2018. We assessed the risk environment over time using a geographic information system to identify and characterize hotspots and noted parallel trends within the syringe discard and ORI data. We identified two notable increases in ORIs per day: the first occurring between 2008 and 2010 (from 0.3 to 0.5), and the second between 2011 and 2014 (from 0.9 to 1.3), following the introduction of fentanyl within local drug markets. We also identified seasonal patterns in the syringe discard, ORI, and overdose data. Through our spatial analyses, we identified significant clusters of discarded syringes, ORIs, and fatal overdoses (p < 0.05), and neighborhoods where high densities of these outcomes overlapped. We found that areas with the highest densities shifted over time, expanding beyond the epicenter of the Downtown neighborhood. Data sharing and analyses among EMS, public health, and academic partners can foster better assessments of local risk environments. Our work, along with new public health efforts in Lowell, led to a city-funded position to improve pick-up and proper disposal of publicly discarded syringes, and better targeted harm reduction services.

Considerations for the Design of Pre-exposure Prophylaxis (PrEP) Interventions for Women: Lessons Learned from the Implementation of a Novel PrEP Intervention

Pre-exposure prophylaxis (PrEP) uptake among women in the United States has been low. To increase uptake, we developed a peer outreach and navigation PrEP intervention. Semi-structured qualitative interviews with 32 cisgender women and 3 transgender women were conducted to assess the intervention. We used a thematic approach to identify barriers to, and facilitators of the intervention. Facilitators included interest in PrEP, offer of health and social services, the intervention’s women-focused approach, and peer outreach and navigation. Barriers were perceived HIV risk, concerns about medication side effects or interactions, housing insecurity and travel, co-occurring health-related conditions, and caregiving responsibilities. We recommend that future interventions consider packaging PrEP in local community settings, such as syringe exchange programs; include services such as food and housing assistance; use peers to recruit and educate women; integrate a culturally appropriate women’s focus; and consider providing same-day PrEP.

Housing Stability and Hepatitis C Infection for Young Adults Who Inject Drugs: Examining the Relationship of Consistent and Intermittent Housing Status on HCV Infection Risk

Housing status affects drug using behaviors, but less is known about the relationship between housing patterns and hepatitis C virus (HCV) infection. HCV-negative young people who inject drugs (PWID) were enrolled into a prospective cohort (2003-2019) with quarterly study visits. We used Cox regression to estimate the independent association of recent housing status (housed vs. unhoused, housing stability, and housing trajectory) on HCV incidence. Among 712 participants, 245 incident HCV infections occurred over 963.8 person-years (py) (cumulative incidence 24.4/100 py). An inverse relationship between time housed and HCV incidence was observed (always unhoused 45.0/100 py, 95% confidence interval (CI) 37.1, 54.5; variably housed 18.0/100 py, 95% CI 15.0, 21.3; and always housed 7.0/100 py, 95% CI 3.0, 17.3). In Cox regression models controlling for confounders, those unhoused versus housed at baseline had a 1.9-fold increased infection risk (95% CI 1.4, 2.6). Those always unhoused versus always housed had a 1.5 times greater risk of HCV (95% CI 1.0, 2.3), and those spending a portion of time in stable housing a lower risk (adjusted relative hazard 0.05, 95% CI 0.3, 0.9) with a similar trend for those being housed for less time. Young adult PWID experiencing both recent and chronic states of being unhoused are at elevated risk for HCV infection. Importantly for this group of PWID, our findings indicate that some frequency of residential housing significantly reduces HCV infection risk.

The Geographic Distribution of Fentanyl-Involved Overdose Deaths in Cook County, Illinois

Objectives. To contrast the geographic distribution of fentanyl-involved and non-fentanyl-involved fatal overdoses between 2014 and 2018 in Cook County, Illinois.Methods. We conducted a spatial analysis using locations of fentanyl-involved fatal overdoses (n = 1433) compared with nonfentanyl opioid and polydrug fatal overdoses (n = 1838) collected through the Cook County Medical Examiner's Office from 2014 to 2018. We also used logistic regression to test significant individual- and neighborhood-level covariates.Results. Fentanyl overdoses geographically clustered more than nonfentanyl overdoses, and this difference was statistically significant. One area in particular showed significantly elevated risk for fentanyl overdoses (P < .05) located in 2 specific neighborhoods of Chicago. The odds of a fentanyl-involved overdose were significantly increased for men, Blacks, Latinos/as, and younger individuals. Neighborhood deprivation score was the only significant neighborhood-level predictor (odds ratio = 1.11; 95% confidence interval = 1.07, 1.17).Conclusions. Fentanyl-involved fatal overdoses follow a distinct geographic distribution associated with resource deprivation in neighborhoods where they occur. This suggests an evolving bifurcated drug market, with drug markets in resource-deprived neighborhoods disproportionately likely to include fentanyl.

Space and Place in Alcohol Research

PURPOSE OF REVIEW

To summarize the recent literature on social and physical environments and their links to alcohol use and identify empirical research strategies that will lead to a better understanding of alcohol use in contexts.

RECENT FINDINGS

Recent research has continued to describe the importance of neighborhood and regional contexts on alcohol use, while a smaller emerging scientific literature assesses the impacts of contexts on drinking.

SUMMARY

The dynamic, longitudinal, and multiscale processes by which social and physical structures affect social interactions and substance use have not yet been uncovered or quantified. In order to understand and quantify these processes, assessments of exposures (e.g., how individuals use space) and risks within specific locations are essential. Methods to better assess these exposures and risks include model-based survey approaches, ecological momentary assessment (EMA) and other forms of ecologically- and temporally-specific analyses, affiliation network analyses, simulation models, and qualitative/multi-methods studies.

Impact of Mobility on Methicillin-Resistant Staphylococcus aureus among Injection Drug Users

In this study, we develop and present a deterministic model for the transmission dynamics of methicillin-resistant staphylococcus aureus (MRSA) among injection drug users. The model consists of non-injection drug users as well as low-and high-risk injection drug users (IDUs). The model further incorporates the movement of these individuals between large metro, suburban and rural areas. The model parameters were estimated by fitting the model to the 2008-2013 disease prevalence data for non-IDUs obtained from the Agency for Healthcare and Research and Quality (AHRQ), as well as the 2009-2013 Census Bureau data for the number of individuals migrating between three different counties in Kansas. Sensitivity analysis was implemented to determine the parameters with the most significant impact on the total number of infected individuals; the transmission probability, recovery rates, and positive behavioral change parameter for the subgroup have the most significant effect on the number of infected individuals. Furthermore, the sensitivity of the parameters in the different areas was the same when the areas are disconnected. When the areas are connected, the parameters in large-metro areas were the most sensitive, and the rural areas were least sensitive. The result shows that to effectively control the disease across the large metro, suburban and rural areas, it is best to focus on controlling both behavior and disease in the large metro area as this has a trickle-down effect to the other places. However, controlling behavior and disease at the same time in all the areas will lead to the elimination of the disease.

Assessing Individuals' Exposure to Environmental Conditions Using Residence-based Measures, Activity Location-based Measures, and Activity Path-based Measures

BACKGROUND

Many approaches are available to researchers who wish to measure individuals' exposure to environmental conditions. Different approaches may yield different estimates of associations with health outcomes. Taking adolescents' exposure to alcohol outlets as an example, we aimed to (1) compare exposure measures and (2) assess whether exposure measures were differentially associated with alcohol consumption.

METHODS

We tracked 231 adolescents 14-16 years of age from the San Francisco Bay Area for 4 weeks in 2015/2016 using global positioning systems (GPS). Participants were texted ecologic momentary assessment surveys six times per week, including assessment of alcohol consumption. We used GPS data to calculate exposure to alcohol outlets using three approach types: residence-based (e.g., within the home census tract), activity location-based (e.g., within buffer distances of frequently attended places), and activity path-based (e.g., average outlets per hour within buffer distances of GPS route lines). Spearman correlations compared exposure measures, and separate Tobit models assessed associations with the proportion of ecologic momentary assessment responses positive for alcohol consumption.

RESULTS

Measures were mostly strongly correlated within approach types (ρ ≥ 0.7), but weakly (ρ < 0.3) to moderately (0.3 ≤ ρ < 0.7) correlated between approach types. Associations with alcohol consumption were mostly inconsistent within and between approach types. Some of the residence-based measures (e.g., census tract: β = 8.3, 95% CI = 2.8, 13.8), none of the activity location-based approaches, and most of the activity path-based approaches (e.g., outlet-hours per hour, 100 m buffer: β = 8.3, 95% CI = 3.3, 13.3) were associated with alcohol consumption.

CONCLUSIONS

Methodologic decisions regarding measurement of exposure to environmental conditions may affect study results.

Combining ecological momentary assessment with objective, ambulatory measures of behavior and physiology in substance-use research

Whereas substance-use researchers have long combined self-report with objective measures of behavior and physiology inside the laboratory, developments in mobile/wearable electronic technology are increasingly allowing for the collection of both subjective and objective information in participants' daily lives. For self-report, ecological momentary assessment (EMA), as implemented on contemporary smartphones or personal digital assistants, can provide researchers with near-real-time information on participants' behavior and mood in their natural environments. Data from portable/wearable electronic sensors measuring participants' internal and external environments can be combined with EMA (e.g., by timestamps recorded on questionnaires) to provide objective information useful in determining the momentary context of behavior and mood and/or validating participants' self-reports. Here, we review three objective ambulatory monitoring techniques that have been combined with EMA, with a focus on detecting drug use and/or measuring the behavioral or physiological correlates of mental events (i.e., emotions, cognitions): (1) collection and processing of biological samples in the field to measure drug use or participants' physiological activity (e.g., hypothalamic-pituitary-adrenal axis activity); (2) global positioning system (GPS) location information to link environmental characteristics (disorder/disadvantage, retail drug outlets) to drug use and affect; (3) ambulatory electronic physiological monitoring (e.g., electrocardiography) to detect drug use and mental events, as advances in machine learning algorithms make it possible to distinguish target changes from confounds (e.g., physical activity). Finally, we consider several other mobile/wearable technologies that hold promise to be combined with EMA, as well as potential challenges faced by researchers working with multiple mobile/wearable technologies simultaneously in the field.

Negotiating space & drug use in emergency shelters with peer witness injection programs within the context of an overdose crisis: A qualitative study

Vancouver, Canada is experiencing an overdose crisis due to the proliferation of fentanyl and related analogues and novel overdose response interventions are being implemented across multiple high overdose risk environments, including emergency shelters. We draw on ethnographic fieldwork and qualitative interviews to examine how social, structural, and physical contexts at two emergency shelters implementing a peer-based supervised injection intervention influenced injection drug use and overdose risks. Findings reveal that the implementation of this intervention reduced stigma and shame through the normalization of drug use in shelter spaces, and yet underlying social norms and material constraints led people to inject alone in non-designated injecting spaces. Whereas these spatial dynamics of injection drug use potentially increased overdose vulnerability, an emerging sense of collective responsibility in relation to the overdose crisis led to the routinization of peer witnessing practices across the shelter environment to extend the impact of the intervention.

Web-Based Survey Application to Collect Contextually Relevant Geographic Data With Exposure Times: Application Development and Feasibility Testing

Background

Although studies that characterize the risk environment by linking contextual factors with individual-level data have advanced infectious disease and substance use research, there are opportunities to refine how we define relevant neighborhood exposures; this can in turn reduce the potential for exposure misclassification. For example, for those who do not inject at home, injection risk behaviors may be more influenced by the environment where they inject than where they live. Similarly, among those who spend more time away from home, a measure that accounts for different neighborhood exposures by weighting each unique location proportional to the percentage of time spent there may be more correlated with health behaviors than one’s residential environment.

Objective

This study aimed to develop a Web-based application that interacts with Google Maps application program interfaces (APIs) to collect contextually relevant locations and the amount of time spent in each. Our analysis examined the extent of overlap across different location types and compared different approaches for classifying neighborhood exposure.

Methods

Between May 2014 and March 2017, 547 participants enrolled in a Baltimore HIV care and prevention study completed an interviewer-administered Web-based survey that collected information about where participants were recruited, worked, lived, socialized, injected drugs, and spent most of their time. For each location, participants gave an address or intersection which they confirmed using Google Map and Street views. Geographic coordinates (and hours spent in each location) were joined to neighborhood indicators by Community Statistical Area (CSA). We computed a weighted exposure based on the proportion of time spent in each unique location. We compared neighborhood exposures based on each of the different location types with one another and the weighted exposure using analysis of variance with Bonferroni corrections to account for multiple comparisons.

Results

Participants reported spending the most time at home, followed by the location where they injected drugs. Injection locations overlapped most frequently with locations where people reported socializing and living or sleeping. The least time was spent in the locations where participants reported earning money and being recruited for the study; these locations were also the least likely to overlap with other location types. We observed statistically significant differences in neighborhood exposures according to the approach used. Overall, people reported earning money in higher-income neighborhoods and being recruited for the study and injecting in neighborhoods with more violent crime, abandoned houses, and poverty.

Conclusions

This analysis revealed statistically significant differences in neighborhood exposures when defined by different locations or weighted based on exposure time. Future analyses are needed to determine which exposure measures are most strongly associated with health and risk behaviors and to explore whether associations between individual-level behaviors and neighborhood exposures are modified by exposure times.

Examining the Social Context of Injection Drug Use: Social Proximity to Persons Who Inject Drugs Versus Geographic Proximity to Persons Who Inject Drugs

In this analysis, we used social network and spatial data to examine associations between people's drug injection status and their social and/or spatial proximity to others who injected drugs. We recruited 503 rural Kentucky residents who used drugs to participate in the Social Networks among Appalachian People (SNAP) Study (2008-2010). Interviewer-administered surveys collected information on recent (past 6 months) sex, drug-use, and social-support network members (n = 897 ties). Using network simulations, we determined a threshold for the association between social proximity to others who injected drugs and recent injection status ("socially proximal" was defined by a shortest path ≤2). We defined "geographically proximal" as the median road-network distance between pairs of individuals who both injected drugs (≤7 miles (≤11.2 km)). Logistic regression was used to determine the independent and joint associations between the number of socially and/or geographically proximal injecting peers and a person's injection status. After adjustment, the odds of recent injection increased by 0.4% for each injecting peer who was geographically proximal but not socially proximal, 12% for each geographically and socially proximal injecting peer, and 22% for each injecting peer who was socially proximal but not geographically proximal. When implementing network-based interventions which promote cessation of injection drug use, investigators should consider collecting sociometric network data to examine whether the intervention diffuses through the network and whether there are additive or threshold effects.

The places parents go: understanding the breadth, scope, and experiences of activity spaces for parents

Neighborhood environments are related to parenting behaviors, which in turn have a life-long effect on children's health and well-being. Activity spaces, which measure individual routine patterns of movement, may be helpful in assessing how physical and social environments shape parenting. In this study we use qualitative data and GIS mapping from 4 California cities to examine parental activity spaces. Parents described a number of factors that shape their activity spaces including caregiving status, the age of their children, and income. Parental activity spaces also varied between times (weekends vs. weekdays) and places (adult-only vs. child-specific places). Knowing how to best capture and study parental activity spaces could identify mechanisms by which environmental factors influence parenting behaviors and child health.

Utilization of Google enterprise tools to georeference survey data among hard-to-reach groups: strategic application in international settings

Background

As geospatial data have become increasingly integral to health and human rights research, their collection using formal address designations or paper maps has been complicated by numerous factors, including poor cartographic literacy, nomenclature imprecision, and human error. As part of a longitudinal study of people who inject drugs in Tijuana, Mexico, respondents were prompted to georeference specific experiences.

Results

At baseline, only about one third of the 737 participants were native to Tijuana, underscoring prevalence of migration/deportation experience. Areas frequented typically represented locations with no street address (e.g. informal encampments). Through web-based cartographic technology and participatory mapping, this study was able to overcome the use of vernacular names and difficulties mapping liminal spaces in generating georeferenced data points that were subsequently analyzed in other research.

Conclusion

Integrating low-threshold virtual navigation as part of data collection can enhance investigations of mobile populations, informal settlements, and other locations in research into structural production of health at low- or no cost. However, further research into user experience is warranted.

Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments

Increasingly, ‘place’, including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions.

Legal space for syringe exchange programs in hot spots of injection drug use-related crime

BACKGROUND

Copious evidence indicates that syringe exchange programs (SEPs) are effective structural interventions for HIV prevention among persons who inject drugs (PWID). The efficacy of SEPs in supporting the public health needs of PWID populations is partially dependent on their accessibility and consistent utilization among injectors. Research has shown that SEP access is an important predictor of PWID retention at SEPs, yet policies exist that may limit the geographic areas where SEP operations may legally occur. Since 2000 in the District of Columbia (DC), SEP operations have been subject to the 1000 Foot Rule (§48-1121), a policy that prohibits the distribution of "any needle or syringe for the hypodermic injection of any illegal drug in any area of the District of Columbia which is within 1000 feet of a public or private elementary or secondary school (including a public charter school)." The 1000 Foot Rule may impede SEP services in areas that are in urgent need for harm reduction services, such as locations where injections are happening in "real time" or where drugs are purchased or exchanged. We examined the effects of the 1000 Foot Rule on SEP operational space in injection drug use (IDU)-related crime (i.e., heroin possession or distribution) hot spots from 2000 to 2010.

METHODS

Data from the DC Metropolitan Police Department were used to identify IDU-related crime hot spots. School operation data were matched to a dataset that described the approximate physical property boundaries of land parcels. A 1000-ft buffer was applied to all school property boundaries. The overlap between the IDU-related crime hot spots and the school buffer zones was calculated by academic year.

RESULTS

When overlaying the land space associated with IDU-related crime hot spots on the maps of school boundaries per the 1000-ft buffer zone stipulation, we found that the majority of land space in these locations was ineligible for legal SEP operations. More specifically, the ineligible space in the identified hot spots in each academic year ranged from 51.93 to 88.29 % of the total hot spot area.

CONCLUSIONS

The removal of the 1000 Foot Rule could significantly improve the public health of PWID via increased access to harm reduction services. Buffer zone policies that restrict SEP operational space negatively affect the provision of harm reduction services to PWID.

Feasibility and Acceptability of Global Positioning System (GPS) Methods to Study the Spatial Contexts of Substance Use and Sexual Risk Behaviors among Young Men Who Have Sex with Men in New York City: A P18 Cohort Sub-Study

Background

No global positioning system (GPS) technology study has been conducted among a sample of young gay, bisexual, and other men who have sex with men (YMSM). As such, the purpose of this study was to evaluate the feasibility and acceptability of using GPS methods to understand the spatial context of substance use and sexual risk behaviors among a sample of YMSM in New York City, a high-risk population.

Methods

Data came from a subsample of the ongoing P18 Cohort Study (n = 75). GPS feasibility and acceptability among participants was measured with: 1) a pre- and post-survey and 2) adherence to the GPS protocol which included returning the GPS device, self-report of charging and carrying the GPS device as well as objective data analyzed from the GPS devices. Analyses of the feasibility surveys were treated as repeated measures as each participant had a pre- and post-feasibility survey. When comparing the similar GPS survey items asked at baseline and at follow-up, we present percentages and associated p-values based on chi-square statistics.

Results

Participants reported high ratings of pre-GPS acceptability, ease of use, and low levels of wear-related concerns in addition to few concerns related to safety, loss, or appearance, which were maintained after baseline GPS feasibility data collection. The GPS return rate was 100%. Most participants charged and carried the GPS device on most days. Of the total of 75 participants with GPS data, 75 (100%) have at least one hour of GPS data for one day and 63 (84%) had at least one hour on all 7 days.

Conclusions

Results from this pilot study demonstrate that utilizing GPS methods among YMSM is feasible and acceptable. GPS devices may be used in spatial epidemiology research in YMSM populations to understand place-based determinants of health such as substance use and sexual risk behaviors.

The Sociospatial Network: Risk and the Role of Place in the Transmission of Infectious Diseases

Control of sexually transmitted infections and blood-borne pathogens is challenging due to their presence in groups exhibiting complex social interactions. In particular, sharing injection drug use equipment and selling sex (prostitution) puts people at high risk. Previous work examining the involvement of risk behaviours in social networks has suggested that social and geographic distance of persons within a group contributes to these pathogens’ endemicity. In this study, we examine the role of place in the connectedness of street people, selected by respondent driven sampling, in the transmission of blood-borne and sexually transmitted pathogens. A sample of 600 injection drug users, men who have sex with men, street youth and homeless people were recruited in Winnipeg, Canada from January to December, 2009. The residences of participants and those of their social connections were linked to each other and to locations where they engaged in risk activity. Survey responses identified 101 unique sites where respondents participated in injection drug use or sex transactions. Risk sites and respondents’ residences were geocoded, with residence representing the individuals. The sociospatial network and estimations of geographic areas most likely to be frequented were mapped with network graphs and spatially using a Geographic Information System (GIS). The network with the most nodes connected 7.7% of respondents; consideration of the sociospatial network increased this to 49.7%. The mean distance between any two locations in the network was within 3.5 kilometres. Kernel density estimation revealed key activity spaces where the five largest networks overlapped. Here, the combination of spatial and social entities in network analysis defines the overlap of vulnerable populations in risk space, over and above the person to person links. Implications of this work are far reaching, not just for understanding transmission dynamics of sexually transmitted infections by identifying activity “hotspots” and their intersection with each social network, but also for the spread of other diseases (e.g. tuberculosis) and targeting prevention services.

The role of social networks and geography on risky injection behaviors of young persons who inject drugs

BACKGROUND

Little is known about young persons who inject drugs (PWID), who are increasingly from suburban communities and predominantly non-Hispanic white.

METHODS

We conducted a cross-sectional personal network (egocentric) and geographic study of young PWID and their drug-using, sexual, and support network members in 2012-13 in metropolitan Chicago, Illinois, U.S.

RESULTS

We enrolled 164 young (median age=26), mostly male (65%), non-Hispanic white PWID (71%), with a self-reported HCV prevalence of 13%. Many (59%) reported multiple residences (i.e., were transient) in the past year, 45% of whom reported living in both urban and suburban places (i.e., were cross-over transients). In multivariable analyses that adjusted for participant and network member characteristics, (1) large injection networks were more common among homeless participants; and (2) syringe sharing was (a) highest among cross-over transients compared to suburban (OR=4.19 95% CI 1.69-10.35) and urban only residents (OR=2.91 95% CI 1.06-8.03), (b) higher among HCV-unknown compared HCV-negative participants (OR=4.62 95% CI 1.69-10.35), (c) more likely with network members who were cross-over transients compared to urban (OR=4.94, 95% CI 2.17-11.23) and (d) less likely with network members with HCV-unknown compared to HCV-negative status (OR=0.4 95% CI 0.19-0.84).

CONCLUSIONS

We identified homelessness as a significant risk factor for large networks and cross-over transience as a significant risk factor for syringe sharing. Further research is needed to understand the role of geographic factors promoting higher risk among these crossover transient PWID.

Individual and neighborhood predictors of mortality among HIV-positive Latinos with history of injection drug use, Florida, 2000-2011

BACKGROUND

The objectives are to examine disparities in all-cause mortality risk among HIV-positive Latinos with injection drug use (IDU) history, and to identify individual- and neighborhood-level predictors.

METHODS

Florida surveillance data for persons diagnosed with HIV 2000-2008 were merged with 2007-2011 administrative data from the American Community Survey. Hazard ratios (HR) were calculated using multi-level weighted Cox regression adjusting for individual and neighborhood (ZCTA-level) factors.

RESULTS

Of 10,989 HIV-positive Latinos, 10.3% had IDU history. Latinos with IDU history were at increased mortality risk compared with Latinos without IDU history after controlling for individual and neighborhood factors (adjusted HR [aHR] 1.61, 95% confidence interval [CI] 1.43-1.80). Factors associated with mortality for those with IDU history included: being 40-59 (aHR 6.48, 95% CI 1.41-121.05) and ≥60 years (aHR 18.75, 95% CI 3.83-356.45) compared with 13-19 years of age; being diagnosed with AIDS within 3 months of HIV (aHR 2.31, 95% CI 1.87-2.86); residing in an area with ≥50% Latinos compared with <25% Latinos (aHR 1.56, 95% CI 1.19-2.04); and residing in a rural compared with an urban area at the time of diagnosis (aHR 1.73, 95% CI 1.06-2.70). Race and neighborhood poverty were not predictors among those with IDU, but were among those without.

CONCLUSION

HIV-positive Latinos with IDU history are at increased mortality risk and have unique contributing factors. Tertiary prevention strategies should target those who are older, diagnosed at later stages, and those who live in predominantly Latino and rural areas.

The interplay between drug-use behaviors, settings, and access to care: a qualitative study exploring attitudes and experiences of crack cocaine users in Rio de Janeiro and São Paulo, Brazil

Background

Despite the growing attention surrounding crack cocaine use in Brazil, little is understood about crack users’ histories, use patterns and the interplay of drug-use behaviors, settings, and access/barriers to care. Qualitative studies seldom cross-compare findings regarding people who use crack from different settings. This study aims to explore the insights of regular crack users in two major Brazilian cities and to examine how social and contextual factors, including stigma and marginalization, influence initial use and a range of health and social issues.

Methods

In-depth interviews and focus groups were conducted with 38 adult crack cocaine users recruited from impoverished neighborhoods in Rio de Janeiro and São Paulo. Interviews and focus groups were audio recorded and transcribed verbatim. Qualitative analysis was carried out, and content was organized and analyzed by recurrent themes relevant to study interests.

Results

For study participants from both cities, frequent crack cocaine use plays a central role in daily life and leads to a range of physical, psychological, and social consequences. Common concerns among users include excessive crack use, engagement in risky habits, infrequent health service utilization, marginalization, and difficulty reducing use.

Conclusions

Disadvantaged conditions in which many crack cocaine users grow up and live may perpetuate risk behaviors and stigma may further marginalize users from necessary health and recovery services. Reducing stigma and moralizing discourse related to drug use, especially among health professionals and law enforcement personnel, may help encourage users to seek necessary care. New harm-reduction-based care and treatment alternatives for marginalized drug users are being developed in parts of Brazil and elsewhere and should be adapted and expanded for other populations in need.