Generational cohort effects on trends in the drug overdose mortality epidemic in the United States

Background: Mortality from drug overdose has increased sharply over recent decades. The purpose of this study is to estimate the variation in overdose mortality across generational cohorts, particularly for white non-hispanic males - a group hit especially hard. Actuaries estimate mortality rates by year-of-birth cohorts for pricing life insurance and annuities. Their Lee-Carter plus cohorts model is applied here to estimate trend by year, pickup rate of trend by age, and cohort impacts on overdose mortality rates in the period 1999-2015 for ages 17-61. Findings: Overdose mortality increased most markedly for the older ages but also for the youngest in this period. Drug mortality for ages 54-61 increased as the pre-boomer generation moved out of this range. The early millennials - born 1981-1990 - have sharply higher mortality rates than any other generation after controlling for age and trend. The later millennials are showing much lower overdose mortality. After adjusting for cohort effects, the trend rate was higher in 1999-2007 than in the following years, but 2013-15 gets back towards the higher trend range. Conclusion: The Lee-Carter plus cohorts model suggests that as they move across the age groups the early millennial cohort will create a bulge in overdose mortality rates that will then subside substantially for the late millennials