Trends in opioid use disorder and overdose among opioid-naive individuals receiving an opioid prescription in Massachusetts from 2011 to 2014

Aims To examine how the risks of incident opioid use disorder (OUD), non-fatal and fatal overdose have changed over time among opioid-naive individuals receiving an initial opioid prescription. Design Retrospective, longitudinal study using the Massachusetts Chapter 55 data set, which linked multiple administrative data sets to study the opioid epidemic. We identified the cumulative incidence of OUD, non-fatal and fatal overdose among the opioid-naive initiating opioid treatment in Massachusetts from 2011 to 2014 and estimated rates of these outcomes at 6 months and at 1, 2, 3 and 4 years to 2015. We used Cox regression to examine the association between characteristics of the initial prescription and risk of these outcomes. Setting Massachusetts, USA. Participants Massachusetts residents aged >= 11 years in 2011-15 who were opioid-naive (no opioid prescriptions or evidence of OUD in the 6 months prior to the index prescription) (n = 2 154 426). The mean age was 49.1 years, 55.3% were female and 47.3% had commercial insurance. Measurements Opioid prescriptions were identified in the Prescription Monitoring Program (PMP) database, as were the characteristics of the initial prescription database. The outcomes of OUD and non-fatal overdose were identified from claims in the All Payer Claims Database (APCD) and hospital encounters in the acute hospital case mix files. Fatal overdoses were identified using Registry of Vital Records and Statistics (RVRS) death certificates and the Office of the Chief Medical Examiner (OCME) circumstances of death and toxicology reports. Findings Among opioid-naive individuals receiving an initial opioid prescription, the risk of incident OUD appears to have declined between 2011 and 2014, while rates of overdose were largely unchanged. For example, the 1-year OUD rate was 1.18% in 2011, 1.11% in 2012, 1.26% in 2013 and 0.94% in 2014. Longer therapy duration was associated with higher risk of OUD [hazard ratio (HR) = 2.24, 95% confidence interval (CI) = 2.19-2.29 for duration of 3 or more months], non-fatal (HR = 1.67, 95% CI = 1.53-1.82) and fatal opioid overdose (HR = 2.24, 95% CI = 1.91-2.61). Concurrent benzodiazepine treatment was also associated with higher risk of OUD (HR = 1.14, 95% CI = 1.12-1.17), non-fatal (HR = 1.20, 95% CI = 1.10-1.30) and fatal overdose (HR = 1.86, 95% CI = 1.61-2.16). Conclusions Among opioid-naive individuals in Massachusetts receiving an initial opioid prescription, the risk of incident opioid use disorder appears to have declined between 2011 and 2014, while rates of overdose were largely unchanged. Longer therapy duration and concurrent benzodiazepines were associated with higher rates of opioid use disorder and opioid overdose.