Response to Letter to the Editor: The Contribution of Prescribed and Illicit Opioids to Fatal Overdoses in Massachusetts, 2013-2015.

Objectives: Opioid-related overdoses are commonly attributed to prescription opioids. We examined data on opioid-related overdose decedents in Massachusetts. For each decedent, we determined which opioid medications had been prescribed and dispensed and which opioids were detected in postmortem medical examiner toxicology specimens. Methods: Among opioid-related overdose decedents in Massachusetts during 2013-2015, we analyzed individually linked postmortem opioid toxicology reports and prescription drug monitoring program records to determine instances of overdose in which a decedent had a prescription active on the date of death for the opioid(s) detected in the toxicology report. We also calculated the proportion of overdoses for which prescribed opioid medications were not detected in decedents' toxicology reports. Results: Of 2916 decedents with complete toxicology reports, 1789 (61.4%) had heroin and 1322 (45.3%) had fentanyl detected in postmortem toxicology reports. Of the 491 (16.8%) decedents with >= 1 opioid prescription active on the date of death, prescribed opioids were commonly not detected in toxicology reports, specifically: buprenorphine (56 of 97; 57.7%), oxycodone (93 of 176; 52.8%), and methadone prescribed for opioid use disorder (36 of 112; 32.1%). Only 39 (1.3%) decedents had an active prescription for each opioid detected in toxicology reports on the date of death. Conclusion: Linking overdose toxicology reports to prescription drug monitoring program records can help attribute overdoses to prescribed opioids, diverted prescription opioids, heroin, and illicitly made fentanyl.