New Opioid Prescriptions among Medicaid Patients Do Not Explain Rising Opioid Overdose Rates

The relationship between prescribed opioid medications and opioid overdose is complex. This study identified patients with apparent new prescriptions for opioid medications in 4 large US state Medicaid programs, and calculated incidence rates of subsequent opioid overdose. Eligible patients were enrolled in Medicaid for 3 years without any prior opioid overdose or prescribed opioid medications before the index opioid prescription.

• 3 million patients met criteria, contributing 246,466 person-years of follow-up data. The median age was 50 years, 64% were female, 38% were white, 7% had a prior substance use disorder (SUD) diagnosis, and 20% had a mental health diagnosis.
• Between 2002 and 2012, 609 opioid overdose events were identified in the cohort. There was a slight, insignificant linear reduction in overdose incidence rates per year of cohort entry.
• Risk factors for incident opioid overdose included younger age, white race/ethnicity, higher initial daily opioid dose, prior SUD, mental health conditions, and prior benzodiazepine prescription (within 30 days of cohort entry).

Comments: This study used data from a time period when prescription opioid overdose rates were rising in the 4 state Medicaid programs studied, yet opioid overdose incidence rates among patients with apparent new prescriptions for opioid medications showed a decreasing—albeit insignificant—trend. It is possible that an increase in illicit prescription opioid use, rather than newly prescribed opioids, was responsible for these disparate trends. Risk factors for opioid overdose in this study largely mirrored those in other populations studied.

Joseph Merrill, MD, MPH

Reference: Nam YH, Bilker WB, DeMayo FJ, et al. Incidence rates of and risk factors for opioid overdose in new users of prescription opioids among US Medicaid enrollees: a cohort study. Pharmacoepidemiol Drug Saf. 2020:29(8):931–938.