Social network predictors of recent and sustained injection drug use cessation: findings from a longitudinal cohort study

Examining the social and behavioral dynamics of substance use in a longitudinal network study in rural Appalachia

BACKGROUND

Prior studies have shown that individuals and their peers often have similar substance use behaviors, but the mechanisms driving these similarities - particularly in rural settings, are not well understood. The primary objectives of this analysis are to (1) identify factors that contribute to relationship turnover and maintenance within a rural network of persons who use drugs (PWUD), (2) determine whether assimilation and/or homophily shape participants use of injection drugs, heroin, and stimulants (methamphetamine and cocaine), and (3) assess the extent that these mechanisms influence networks ties and/or behaviors and whether these effects vary across time.

METHODS

Sociometric network data were collected from a cohort of PWUD in rural Eastern Kentucky at baseline (2008-2010) and at four follow-up visits conducted approximately semiannually. Stochastic actor-oriented models (SAOMS) were used to model network structure and participant behaviors as jointly dependent variables and to identify characteristics associated with the maintenance, dissolution, and formation of network ties and changes in drug use behaviors.

RESULTS

Findings suggest (1) greater network stability over time for reciprocal and transitive relationships, (2) both homophily and assimilation played a greater role in shaping injection drug use (IDU) initiation and cessation than they did in shaping heroin and stimulant use, and (3) the importance of these mechanisms appeared consistent over time.

CONCLUSION

Given the stability of particular network structures and evidence of both homophily and assimilation with respect to drug-use behaviors, interventions that leverage social networks could be used to motivate health-promoting behaviors.

A social network analysis approach to assess COVID19-related disruption to substance use treatment and informal social interactions among people who use drugs in Scotland

AIMS

To assess the extent of Coronavirus-related disruption to health and social care treatment and social interactions among people with lived or living experience of substance use in Scotland, and explore potential reasons for variations in disruption.

DESIGN

Cross sectional mixed methods interview, incorporating a social network 'egonet interview' approach asking about whether participants had interactions with a range of substance use, health, social care or third sector organisations, or informal social interactions.

SETTING

Five Alcohol and Drug Partnership Areas in Scotland.

PARTICIPANTS

57 (42% women) participants were involved in the study, on average 42 years old.

MEASUREMENTS

Five-point Likert scale reporting whether interactions with a range of services and people had gotten much better, better, no different (or no change), worse, or much worse since COVID19 and lockdown. Ratings were nested within participants (Individuals provided multiple ratings) and some ratings were also nested within treatment service (services received multiple ratings). The nested structure was accounted for using cross classified ordinal logistic multilevel models.

FINDINGS

While the overall average suggested only a slight negative change in interactions (mean rating 2.93), there were substantial variations according to type of interaction, and between individuals. Reported change was more often negative for mental health services (Adjusted OR = 0.93 95% CI 0.17,0.90), and positive for pharmacies (3.03 95% CI 1.36, 5.93). The models found between-participant variation of around 10%, and negligible between-service variation of around 1% in ratings. Ratings didn't vary by individual age or gender but there was variation between areas.

CONCLUSIONS

Substance use treatment service adaptations due to COVID19 lockdown led to both positive and negative service user experiences. Social network methods provide an effective way to describe complex system-wide interaction patterns, and to measure variations at the individual, service, and area level.

Effects of Online Friendships on Safer Sex Communication and Behavior among Black Sexual Minority Men: A Study of Network Exposure

This study draws on social normative and social learning theories to examine the masspersonal safer sex communication (i.e., Facebook posts about safer sex) and safer sex behavior (i.e., condom use) in a cohort of Black sexual minority men (BSMM) (N = 340), with an eye toward understanding their relationship with the safer sex communication and behaviors of their BSMM Facebook friends. Using linear network autocorrelation regression models, results showed that BSMM's safer sex communication and condom use behavior were each associated with the communication and behavior of their online peers. Specifically, BSMM's condom use was positively associated with their friends' condom use and friends' safer sex communication, and BSMMs' safer sex communication was positively associated with friends' safer sex communication. Moreover, contrary to prior research, BSSM's safer sex communication and condom use were not related to one another, suggesting that talking about safer sex on social media should not be interpreted to be an indication of engageDment in safer sex behavior. These findings underscore an opportunity to leverage peer influence in social media networks, particularly in the form of masspersonal communication, to encourage cascades of safer sex messaging among peers and adoption of safer sex behavior.

Network-level HIV risk norms are associated with individual-level HIV risk and harm reduction behaviors among people who inject drugs: a latent profile analysis

The COVID-19 related U.S.-Mexico border-crossing restrictions disrupted social networks and HIV harm reduction services among people who inject drugs (PWID) in San Diego and Tijuana. We assessed associations of descriptive network norms on PWID's HIV vulnerability during this period. Between 10/2020 and 10/2021, 399 PWID completed a behavioral and egocentric questionnaire. We used Latent Profile Analysis to categorize PWID into network norm risk profiles based on proportions of their network (n = 924 drug use alters) who injected drugs and engaged in cross-border drug use (CBDU), among other vulnerabilities. We used logistic and linear regressions to assess network profile associations with individual-level index of HIV vulnerability and harm reduction behaviors. Fit indices specified a 4-latent profile solution of descriptive network risk norms: lower (n = 178), moderate with (n = 34) and without (n = 94) CBDU and obtainment, and higher (n = 93). Participants in higher risk profiles reported more HIV vulnerability behaviors and fewer harm reduction behaviors. PWID's gradient of HIV risk was associated with network norms, warranting intervention on high-vulnerability networks when services are limited.

Perceived HIV Treatment Norms Modify the Association Between HIV-Related Stigma and Adherence to Antiretroviral Therapy Among Persons Living with HIV in Baltimore, Maryland

Adherence to antiretroviral therapy (ART) is associated with reduced HIV-related morbidity/mortality and ongoing transmission; however, the extent to which this association is modified by perceived HIV treatment norms is unknown. 270 PLWH completed a survey to assess demographics, risk behaviors, stigma, ART adherence, and perceived HIV treatment norms (Baltimore, 2014-2017). We used modified Poisson regression to examine effect modification by perceived HIV treatment norms. The association between HIV-related stigma and ART adherence was modified by perceived HIV treatment norms. Among individuals who perceived that friends/family were sub-optimally adherent, HIV-related stigma was negatively associated with ART adherence (Adjusted Risk Ratio [ARR] = 0.36; 95%CI 0.15-0.87). Among those who perceived optimal adherence among friends/family, the relationship between HIV-related stigma and ART adherence was not statistically significant (ARR = 1.07; 95%CI 0.65-1.76). Interventions to improve ART adherence among those who are sub-optimally adherent could focus on increasing perceptions of ART adherence among their friends/family.

Using conjoint analysis to study health policy changes: An example from a cohort of persons who use drugs

BACKGROUND

Historically, persons who use drugs (PWUDs) in the United States have often lacked health insurance, as Medicaid did not cover low-income adults. The Affordable Care Act of 2010 (ACA) increased access to insurance in states, such as Kentucky, that expanded their Medicaid programs. A cohort study of PWUDs in Kentucky found the prevalence of being insured increased from 34% pre-ACA to 87% post-ACA. However, changes to Medicaid were proposed that intended to restrict access to this program. This manuscript describes the feasibility and utility of conjoint analysis, an innovative method for studying decision-making, to identify potential impacts of health policy changes on PWUDs.

METHODS

IBM SPSS's "orthogonal design" command was used to construct 12 policy profiles that presented varying combinations of the proposed policy changes to Kentucky's Medicaid plan. Each policy profile presented information on (1) monthly premium costs, (2) penalties for not paying monthly premiums, (3) weekly work requirements, and (4) if their preferred physician accepted the plan for payment. Readability of the policy profiles was analyzed using the Readable.io application. The policy profiles were included in a recent follow-up of a longitudinal cohort of PWUDs in Appalachian Kentucky (n = 355). Participants rated the likelihood of enrolling in each policy profile's Medicaid plan, using a scale ranging from 0=not at all likely to 10=extremely likely. Data were analyzed using SPSS's conjoint analysis commands.

RESULTS

Readability results indicated the policy profiles required a 3^rd grade education. Nearly all participants responded to each of the 12 policy profiles. Across the policy profiles, the mean response for willingness to enroll was 3.43 (SD = 3.61), indicating relatively low willingness to enroll. Conjoint analysis revealed the two most influential factors on willingness to enroll were work requirements (importance score, IS = 77.63) and monthly premium costs (IS = 17.76). Penalties for nonpayment (IS = 0.43) and physician acceptance (IS = 4.13) had minimal influence.

CONCLUSIONS

This research demonstrates the feasibility of using conjoint analysis to study the impacts of potential policy changes on PWUDs.