Faculty Bibliography

BACKGROUND:Overdose rates in the U.S. rose dramatically during the COVID-19 pandemic. Well-documented racial and sociodemographic inequities in the impact of the pandemic suggest the potential for similar inequities for overdose. Our objective was to identify subgroups of New York State Medicaid enrollees who experienced the greatest increases in non-fatal opioid overdose risk following onset of the COVID-19 pandemic. METHODS:Data are from a retrospective cohort of 1,021,889 people enrolled in New York State Medicaid from 2019-2020. To identify subgroups with the greatest increased risk of non-fatal overdose following onset of the COVID-19 pandemic, we used Heterogeneous Treatment Effect (HTE)-Scan, a novel machine learning method developed for accurate and computationally efficient discovery of heterogeneous treatment effects in complex data. RESULTS:In the total sample, risk of non-fatal opioid overdose increased 22% after onset of the pandemic. We also identified two subgroups with elevated risk relative to the total sample: subgroup 1 (Black and Hispanic males aged 45-64 years old with no baseline documentation of opioid use disorder (OUD); N = 53,065) and subgroup 2 (people aged 45-64 years old with documented aged/blind/disabled status and no baseline documentation of OUD; N = 73,694). These subgroups experienced a 54% and 57% increase in non-fatal overdose risk, respectively. CONCLUSIONS:We estimated heterogeneous effects of onset of the COVID-19 pandemic on non-fatal overdose, with elevated risks estimated for older working-aged, structurally disadvantaged adults without documented OUD. These findings illustrate the importance of structural factors in driving heterogeneous risk of overdose following complex social events.

BACKGROUND:Overdose prevention centers (OPCs) may reduce public drug use and, with it, policing of people who use drugs in the communities surrounding these sites. We applied an augmented synthetic control method to assess changes in pedestrian stops before and after the November 2021 opening of two OPCs (Washington Heights and East Harlem) in New York City (NYC). METHODS:We retrieved pedestrian stop information from the New York Police Department's (NYPD) Stop, Question, and Frisk, program from January 2017 to December 2024, and created bimonthly averages using five- and ten-minute walking buffers surrounding the OPCs and 57 donor sites (syringe service and opioid treatment programs) as outcomes. Covariates were derived from American Community Survey, NYPD Calls for Services, and SafeGraph pedestrian mobility estimates. RESULTS:The opening of the Washington Heights OPC was associated with a reduction of 2.8 bimonthly average pedestrian stops in the post-intervention period when using five-minute walking buffers, although results were compatible with increases and reductions (95%CI=-9.4, 4.0). For ten-minute walking buffers, results were compatible with a wide range of reductions (ATT=-9.2 [95%CI=-18.3, -1.3]). East Harlem OPC showed larger point estimates when examining both distances (ATT=-8.4 [95%CI=-12.2, -4.5] and ATT=-13.7 [95%CI=-22.1, -4.2] with five- and ten-minute walking buffers, respectively). For both sites, permutation tests suggested that these reductions fell within the range of possible donor-unit placebo effects. CONCLUSIONS:Our study shows limited evidence of an effect of NYC's first two OPCs on pedestrian stops in their immediate vicinity, with a potential decrease concentrated in the first two years at the East Harlem location.

OBJECTIVE:To examine the prevalence of categorical self-reported opioid misuse and compare it to a post hoc corrected indicator in the general Mexican population. MATERIALS AND METHODS/METHODS:We used data from the 2025 Encuesta Nacional de Consumo de Drogas, Alcohol y Tabaco. We constructed indicators from self-reported categorical heroin/fentanyl use, prescription opioids misuse and opioid misuse and post hoc corrected versions based on the review of open-ended follow up questions by two experts. We estimated the prevalence from categorical self-report responses and compared it with the post hoc corrected indicators. RESULTS:The prevalence of self-reported prescription opioid misuse was 1 948.3 per 100 000 people, which decreased to 1 242.4 after correction. Self-reported heroin or fentanyl use was 370.7 per 100 000 people, with a corrected prevalence of 326.2. Self-reported opioid misuse had a prevalence of 2 229.6 per 100 000 people, which decreased to 1 482.3 after correction. CONCLUSION/CONCLUSIONS:Misclassification was more frequent for prescription opioid misuse than for illicit opioid use. Simple categorical questions performed well for measuring illicit opioid use, but they moderately overestimated prescription and overall opioid misuse.

Cannabis policies vary from strict prohibition to commercialised legalisation and are rapidly evolving worldwide. Here, we reviewed evidence for associations between international cannabis policy changes from 2000-25 and cannabis use, cannabis use disorder, and other psychiatric disorders. Commercialised legal markets for non-medical use in Canada and the USA were associated with increased prevalence of cannabis use and cannabis use disorder in adults and increases in cannabis potency since legalisation. There was no consistent evidence for associations between policy change and the prevalence or incidence of psychotic disorders. Commercialised legalisation was associated with an increase in hospital admissions for psychosis, and for psychotic disorders comorbid with cannabis use disorder. Poorly regulated legal access to medical cannabis, in the absence of efficacy and safety data, could increase risk of harm. Policies that limit commercialisation, such as strictly regulated legalisation of medical or non-medical supply, were not as strongly associated with cannabis use or psychiatric disorders, but long-term evaluation is needed. There was little evidence that decriminalisation of non-medical cannabis in Europe, Africa, Oceania, and Asia was associated with cannabis use or psychiatric disorders.

BACKGROUND AND AIMS/OBJECTIVE:The opioid crisis is still a public health emergency in the United States, despite recent declines in opioid overdose deaths (OODs) and increased availability of evidence-based practices (EBPs) for opioid use disorder (OUD). The geographic variability in OODs drives the need for localized decision-making, where interventions are tailored to the unique needs of communities. This study aimed to develop and calibrate a simulation model that evaluates the impact of enhanced implementation of EBP on OODs at the community-level. DESIGN/METHODS:We developed OPSiM (Opioid Policy Simulation Model), a community-level microsimulation model that simulates the course of opioid use, OUD, treatment, recovery and overdose-related events. The model was parameterized with data from the HEALing Communities Study and looked at six scenarios of EBPs implemented in 2025 with sustainment through 2030: (1) maintain 2024 EBP levels (status quo); (2) increase initiation of medications for opioid use disorder (MOUD); (3) increase MOUD retention; (4) increase MOUD initiation and retention; (5) increase distribution of naloxone; and (6) both scenarios 4 and 5. SETTING/METHODS:Twenty-nine communities in Massachusetts, New York, and Ohio, USA. PARTICIPANTS/METHODS:Simulated community residents with non-prescribed opioid use or OUD. MEASUREMENTS/METHODS:Estimated number of OODs per 100 000 individuals between 2025 and 2030 in each community, averaged across the 26 communities. FINDINGS/RESULTS:Under the status quo, the model projected 158 OODs (range across communities: 39-468) per 100 000 individuals between 2025 and 2030. Increasing medications for the treatment of OUD (MOUD) retention alone reduced OODs by 6% (range: 3-15%), while increasing MOUD initiation alone reduced OODs by 9% (range: 8-12%). Increasing both MOUD initiation and retention had a synergistic effect, reducing OODs by 21% (range: 15-31%). Reduction in OODs in response to increased MOUD initiation and/or retention was similar across urban and rural communities. The effect of increasing naloxone distribution varied substantially across communities due to differing saturation levels; in some communities, additional naloxone kits provided only marginal benefits. Rural communities were further from saturation whereas most urban communities were at or close to saturation. CONCLUSIONS:A tailored, multi-pronged approach that scales up medications for opioid use disorder alongside widespread naloxone distribution, and that addresses community-specific needs and capacities, will be most effective at reducing opioid overdose deaths in the United States.

BACKGROUND/UNASSIGNED:The opioid overdose crisis remains a public health emergency in the United States. Evidence-based practices-including medications for opioid use disorder (MOUD) and naloxone distribution-can reduce harms, but their community-level cost-effectiveness is uncertain and may vary locally. We aimed to evaluate the cost-effectiveness of enhanced community-level implementation of evidence-based practices for opioid use disorder (OUD). METHODS/UNASSIGNED:We used a validated microsimulation model of OUD, calibrated with data from the HEALing Communities Study across 26 highly impacted communities in Massachusetts, New York, and Ohio. Six intervention scenarios for 2025-2030: maintaining 2024 evidence-based practice levels (status quo); improved naloxone distribution; improved MOUD retention; improved MOUD initiation; combined initiation and retention; and combined initiation, retention, and naloxone distribution. Outcomes included opioid overdose deaths (OODs), non-overdose opioid-related deaths, quality-adjusted life years (QALYs), costs (healthcare and societal), and incremental cost-effectiveness ratios (ICERs). FINDINGS/UNASSIGNED:Maintaining 2024 evidence-based practice levels was projected to yield OODs of 39-468 per 100,000 and non-overdose deaths of 238-3018 per 100,000 across communities. Enhancing MOUD initiation, retention, and naloxone distribution reduced OODs by 15-40% and non-overdose deaths by 7-24%, producing the largest QALY gains (1006-38,292). From the healthcare perspective, improved initiation plus retention was cost-effective in all communities (ICER US$11,765-US$91,058 per QALY); from the societal perspective, all enhanced scenarios were cost-saving (US$121 million-US$4.74 billion net savings). INTERPRETATION/UNASSIGNED:Community-level enhancement of MOUD initiation and retention, and for some communities also enhancing naloxone distribution, can substantially reduce opioid-related-overdose and non-overdose-deaths. These strategies are cost-effective from a healthcare perspective and cost-saving from a societal perspective, supporting investment in comprehensive, community-tailored interventions. FUNDING/UNASSIGNED:NIH HEAL Initiative.

We estimated the extent to which different pain management practices, considered together as well as individually, mediated the relationship between chronic pain or physical disability and new-onset opioid use disorder (OUD) in a large cohort of adult Medicaid patients. Considering the plausibility of the assumptions required to identify different mediational estimands, we estimated natural indirect effects when considering mediation through the group of mediators together and estimated interventional indirect effects when considering mediation through each pain management practice individually. We estimated each effect using a nonparametric one-step estimator. The pain management variables we examined mediated all of the total effect of chronic pain on OUD risk and nearly half of the total effect of physical disability on OUD risk. High-dose, long-duration opioid prescribing and co-prescription of opioids with benzodiazepines, gabapentinoids, and muscle relaxants each contributed substantially to the increased risk of OUD due to chronic pain (contributing to 10-37% of the overall effect) and more moderately to the increased risk of OUD due to physical disability (contributing to 3-19% of the overall effect). Antidepressant or anti-inflammatory prescribing and physical therapy generally did not contribute to increased OUD risk, and, in some cases, even contributed to small reductions in risk.

Given substantial reporting delays in overdose deaths, state health departments increasingly use non-fatal overdose data to inform geographically targeted rapid overdose response efforts. We sought to evaluate the extent to which non-fatal overdose events were associated with concurrent and future overdose deaths in Rhode Island. We aggregated non-fatal overdose data from emergency medical services records (2019-2023) and fatal overdose data from the State Unintentional Drug Overdose Reporting System (2020-2023) in 1-, 3-, and 6-month intervals at census block group and census tract levels. Rates of fatal overdose were estimated, relative to non-fatal overdose lagged by 0-12 months, using negative binomial regression, and relative to monthly spikes in non-fatal overdose burden, using zero-inflated Poisson regression. Estimation was implemented using integrated nested Laplace approximation. Each additional non-fatal overdose event per census block group was associated with fatal overdose rates that were 48% higher (95% credible interval: 1.37-1.59) than expected in concurrent months, with smaller associations at the census tract level, in wider time intervals, and when non-fatal overdose data were lagged. Spikes in non-fatal overdose activity were associated with elevated overdose mortality in concurrent periods with fine temporal and geographic granularity, but not in larger time frames and geographic areas.

IMPORTANCE/UNASSIGNED:Syringe services programs (SSPs) are evidence-based interventions that reduce bloodborne infections and injection-related harms among people who inject drugs, yet access remains limited and geographically uneven across the US. OBJECTIVE/UNASSIGNED:To quantify the travel time, distance, and cost required to reach the nearest SSP from population-weighted census tracts nationwide and to examine differences by urbanicity, state, and SSP legality. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This cross-sectional geospatial study linked all known SSP locations as of August 2024 to the population-weighted centroids of census tracts in the 50 US states and the District of Columbia. Analyses were conducted between December 2024 and February 2026. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Population-weighted mean and median driving time, distance, and cost to access the nearest SSP, stratified by National Center for Health Statistics urban-rural county category and SSP legal status. Costs were estimated using 2024 Internal Revenue Service (IRS) medical mileage deduction rates and 2022 state-specific gasoline prices. RESULTS/UNASSIGNED:In 1338 SSPs across 83 780 census tracts, the population-weighted mean 1-way driving time to the nearest SSP was 46.1 minutes (95% CI, 45.7-46.5 minutes) and the median was 23.3 minutes (IQR, 12.2-58.5 minutes). Altogether, 23.1% of the population lived more than 60 minutes from an SSP and 12.6% lived over 120 minutes away. The mean 1-way driving distance was 41.8 miles (95% CI, 41.3-42.2 miles). The mean 1-way driving cost was $8.77 (95% CI, $8.68-$8.86) using the 2024 IRS mileage rate and $6.91 (95% CI, $6.84-$6.98) using state mean gasoline prices in 2022. In states where SSPs were legal, mean driving time was 30.1 minutes (95% CI, 29.8-30.4 minutes) and mean cost by IRS mileage rates was $4.94 (IQR, $4.88-$5.00), compared with 110.7 minutes (95% CI, 109.6-111.8 minutes) and $24.19 (IQR, $23.92-$24.46) in states where SSPs were illegal. CONCLUSIONS AND RELEVANCE/UNASSIGNED:This cross-sectional study of travel burden to SSPs found substantial geographic and financial barriers to accessing SSPs across the US, particularly in nonmetropolitan areas. Targeting new SSPs to areas with the greatest travel burden could improve utilization and reduce drug-related morbidity.

Overdose prevention centers (OPCs) are associated with improved community health and decreased crime, but opponents argue that OPCs depress nearby property values. We estimated the association of the opening of the first two public recognized OPC in the United States with neighborhood residential rents and real estate sales in the East Harlem and Washington Heights neighborhoods of New York City (NYC). Using augmented synthetic controls, we analyzed quarterly and semiannual rental listings and annual and semiannual sales within 300- and 500-meter buffers around the OPCs. Donor units were buffers around syringe service programs without OPCs and opioid treatment programs. Primary outcomes were median quarterly rental listing price and median annual sales price. Overall, we found no changes in neighborhood rental or sales prices. For quarterly rentals at 300 m, we estimated (ATT, 95% CI) $145 (-$780, $1070) in East Harlem and -$505 (-$1279, $269) in Washington Heights. For annual sales at 500 m, we estimated -$542 993 (-$1 228 024, $142038) in East Harlem and $1 121 706 (-$431 285, $2674697) in Washington Heights. Conformal inference identified no detectable time-point effects. Overall, OPC implementation in NYC was not associated with changes in rents or sales, suggesting these facilities may not generate appreciable effects on local housing values.