Temporal and generational changes in depression among young American adults

Abstract

The prevalence of depression among young American adults has risen significantly over the past two decades, but the mechanisms that underlie the population-level changes in depressive symptoms severity remain unclear. We used data from the 2005–2023 National Health and Nutrition Examination Survey (NHANES) and hierarchical age–period–cohort (HAPC) analysis to examine developmental (i.e., age), life stage (i.e., period), and generational (i.e., cohort) distribution of depressive symptoms among American adults aged 20–30 years old over an 18-year period. Our model results indicate that the probability of either mild, moderate, or severe depression increased among young adult females and males between 2005 and 2023 due to a positive age, period, and cohort effect. Specifically, when we consider the historical context (i.e., period-specific changes) and the generational shift (i.e., birth cohort membership), the youngest women and men have the highest probability of either mild or moderate depression, but the probability of severe depression increases among the individuals of both sexes with each consecutive year of age. Policy makers must develop population-level depression prevention strategies that focus on age and sex differences in illness symptoms severity.