Alcohol or Drug Self-Help Use Among Adults in the United States: Age, Period, and Cohort Effects Between 2002 and 2018

In the context of an ongoing and worsening drug overdose epidemic in the USA, increases in free support services like self-help groups may be expected. We estimated differences in self-help use by age, period, or cohort among people who may have needed treatment. We included N = 92,002 adults from the 2002–2018 National Surveys on Drug Use and Health who met past-year DSM-IV substance use disorder criteria or received alcohol/drug treatment in any location. We used hierarchical age-period-cohort (HAPC) modeling to estimate average age-period-cohort associations with self-help. Level-1 covariates included age, race and ethnicity, household income, and sex. We quantified level-2 variance components using the median odds ratio (MOR). We found small positive HAPC period effects for alcohol/drug self-help that were driven by alcohol-specific effects. Birth cohort differences were observed starting at age 48. Younger birth cohorts, especially among Black adults, were less likely to report self-help use than older birth cohorts. MOR was consistently elevated for cohort effects (MOR = 1.17; covariance parameter: 0.15; 95% CI [0.11, 0.23]) but not for period effects. Overall, self-help use did not increase in the context of substantial treatment needs and worsening overdose racialized disparities. Instead, cohort effects explained trends in alcohol/drug self-help. Findings could indicate that younger birth cohorts may need additional supports, especially services tailored for Black and Hispanic people.