Spatial proximity and access to buprenorphine or methadone treatment for opioid use disorder in a sample of people misusing opioids in Southern California.

BACKGROUND: In response to the opioid crisis, over the last 10 years substantial strides have been made to increase the availability of evidence-based treatments for opioid use disorder, in particular buprenorphine maintenance, in the United States. Despite these worthwhile efforts, uptake rates of evidence-based treatment remain relatively low. As part of a broader study of opioid misuse, we examined proximity to evidence-based treatment as a potential barrier to treatment access. METHODS: In 2017-2018, we surveyed 218 individuals misusing prescription opioids or using street opioids in three Southern Californian counties. The study calculated driving distance from place of residence to the closest treatment provider offering buprenorphine or methadone treatment for opioid use disorders. RESULTS: Median distance to providers was 3.8 km (2.4 miles). Seventy one (33%) participants had received some form of treatment in the last 3 months; however, only 26 (40%) of these had received buprenorphine or methadone maintenance treatment. Participants receiving treatment at the time of their interview were traveling an average 16.8 km (10.4 miles) to reach treatment, indicating that as a group this population was both willing and able to seek and engage with treatment. CONCLUSIONS: In the suburban and exurban communities in which our study was based, our findings suggest that simple physical proximity to providers of evidence-based treatment for opioid use disorder is no longer a critical barrier. Other barriers to uptake of buprenorphine or methadone maintenance treatment clearly remain and need to be addressed. DISCLAIMER: Findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

Transitioning from pharmaceutical opioids: A discrete-time survival analysis of heroin initiation in suburban/exurban communities.

INTRODUCTION: Research identifying pathways to heroin use has typically been conducted among urban populations. This study examined heroin initiation following pharmaceutical opioid use in three suburban/exurban Southern California counties. METHODS: Interviewer-administered surveys collected data among 330 participants (65.9 % male; 63.9 % non-Hispanic white) whose initial use of any opioid was a pharmaceutical opioid. Retrospective discrete-time survival analysis identified predictors of heroin initiation, measured as self-reported age of first heroin use. RESULTS: Median age of first pharmaceutical opioid use was 17 years; 50.6 % initially acquired pharmaceutical opioids from an illicit source, 56.7 % first used pharmaceutical opioids for recreational purposes, and 86 % initiated heroin use. Average time from first pharmaceutical opioid use to first heroin use was 8.2 years. Drug/alcohol treatment (adjusted Hazard Ratio [aHR]: 0.67, 95 % CI: 0.50, 0.88) was associated with delayed time to heroin initiation. Obtaining opioids from non-medical sources (aHR: 2.21, 95 % CI: 1.55, 3.14) was associated with accelerated time to heroin initiation. Reporting supply problems with obtaining pharmaceutical opioids (e.g., unable to acquire pharmaceutical opioids) was associated with accelerated time to heroin initiation, but the magnitude of this effect was dependent on one's history of methamphetamine use (p < 0.05). CONCLUSIONS: Time to heroin initiation following pharmaceutical opioid use was accelerated among those reporting supply problems and delayed among those with exposure to substance use treatment. Interventions interrupting supply of opioids might benefit from coordination with evidence-based medication-assisted treatment to minimize the risk of transitioning to heroin use, particularly among those with a long history of non-prescribed pharmaceutical opioid use.

The longitudinal association of venue stability with consistent condom use among female sex workers in two Mexico-USA border cities.

We examined the relationship between venue stability and consistent condom use (CCU) among female sex workers who inject drugs (FSW-IDUs; n = 584) and were enrolled in a behavioural intervention in two Mexico-USA border cities. Using a generalized estimating equation approach stratified by client type and city, we found venue stability affected CCU. In Tijuana, operating primarily indoors was significantly associated with a four-fold increase in the odds of CCU among regular clients (odds ratio [OR]: 3.77, 95% confidence interval [CI]: 1.44, 9.89), and a seven-fold increase among casual clients (OR: 7.18, 95% CI: 2.32, 22.21), relative to FSW-IDUs spending equal time between indoor and outdoor sex work venues. In Ciudad Juarez, the trajectory of CCU increased over time and was highest among those operating primarily indoors. Results from this analysis highlight the importance of considering local mobility, including venue type and venue stability, as these characteristics jointly influence HIV risk behaviours.