An exploratory analysis of 5-alpha reductase inhibitors and risk of opioid use disorder among male Medicare beneficiaries receiving prescription opioid medications.

Background: Opioid use disorder (OUD) imposes a significant socioeconomic burden, highlighting the need for new interventions.

Objective: This study investigated whether exposure to 5-alpha reductase inhibitors (5αRIs) is associated with a lower risk of developing OUD.

Methods: A cohort study was conducted using Medicare data from 2017 to 2019. Male subjects identified as receiving at least one opioid medication were propensity score matched based on exposure to a 5αRI medication. The primary outcome of interest was a diagnosis of OUD occurring following opioid exposure. Additionally, the study compared the number of morphine milliequivalents (MME) and the count of opioid prescription claims between the groups.

Results: We identified 467,399 subjects who had received at least one opioid prescription. Among these, 19,176 beneficiaries were receiving a 5αRI before opioid medication exposure and were matched 1:1 to non-users. Use of 5αRI was associated with a reduced risk of OUD (OR = 0.63, 95% CI: 0.53-0.75). MME for subjects exposed to 5αRI was significantly lower than for those without 5αRI exposure (p < .001). Furthermore, there was a significant difference in the number of opioid prescription claims between the groups, with those taking a 5αRI having an average of 6.0 (SD = 10.1) prescriptions as compared to 6.7 (SD = 13.0) for those not receiving a 5αRI (p < .001).

Conclusions and scientific significance: This first of its kind in humans study suggests that concomitant use of opioids and 5αRI is associated with a reduction in OUD and maybe a preventive therapy for patients at risk of OUD. Our findings align with animal models that have shown similar findings.