Comparing Medicaid Enrolment Death Data to State-Wide Death Records in Maine

Death data available in Medicaid enrolment files may be incomplete and lack cause of death information. We sought to compare Medicaid enrolment death data to state-wide death records in Maine.

(1) To compare the date of death of Medicaid enrollees in Maine according to the Medicaid enrolment data to the date of death obtained through an ongoing quarterly death certificate-Medicaid linkage for 2016-2023; and (2) using the death certificate-Medicaid linkage data, to perform an analysis of the risk of drug overdose death in 2023 by opioid use disorder (OUD) status in 2023, as part of monitoring activities required for one of Maine's new approaches to delivering Medicaid services.

We used Maine Medicaid enrolment data 2010 through 2023 and claims data 2016 through 2023, and Maine final death certificate data 2016 through 2023 (plus Q1-Q2 2024 provisional data). We estimated the risk of drug overdose death in 2023 by OUD diagnosis among non-elderly adults in 2023 using underlying cause of death information from the death certificate-Medicaid linkage data file.

There were 124,510 deaths in Maine among Maine residents from 2016 to 2023. Among Medicaid enrollees each year, there was a slightly higher number of deaths when using the death certificate-Medicaid linkage data than when using current enrolment data (e.g. 12% vs. 11% among 2016 enrollees), but generally, death counts were consistent (90% found in both data sources). In our analysis of death certificate-Medicaid linkage data, we found the risk of drug overdose death in 2023 was 0.68% among those with OUD and 0.11% among those without OUD (risk ratio = 6.1).

Generally, there was good agreement between the two sources on the date of death. However, only ongoing death certificate-Medicaid linkage allows for examination of the cause of death, which is required for monitoring a new approach to delivering Medicaid services in Maine.