Prior Incarceration Is Associated with Poor Mental Health at Midlife: Findings from a National Longitudinal Cohort Study.

Background: People with mental illnesses and people living in poverty have higher rates of incarceration than others, but relatively little is known about the long-term impact that incarceration has on an individual's mental health later in life.

Objective: To evaluate prior incarceration's association with mental health at midlife.

Design: Retrospective cohort study PARTICIPANTS: Participants from the National Longitudinal Survey of Youth 1979 (NLSY79)-a nationally representative age cohort of individuals 15 to 22 years of age in 1979-who remained in follow-up through age 50.

Main Measures: Midlife mental health outcomes were measured as part of a health module administered once participants reached 50 years of age (2008-2019): any mental health history, any depression history, past-year depression, severity of depression symptoms in the past 7 days (Center for Epidemiologic Studies Depression [CES-D] scale), and mental health-related quality of life in the past 4 weeks (SF-12 Mental Component Score [MCS]). The main exposure was any incarceration prior to age 50.

Key Results: Among 7889 participants included in our sample, 577 (5.4%) experienced at least one incarceration prior to age 50. Prior incarceration was associated with a greater likelihood of having any mental health history (predicted probability 27.0% vs. 16.6%; adjusted odds ratio [aOR] 1.9 [95%CI: 1.4, 2.5]), any history of depression (22.0% vs. 13.3%; aOR 1.8 [95%CI: 1.3, 2.5]), past-year depression (16.9% vs. 8.6%; aOR 2.2 [95%CI: 1.5, 3.0]), and high CES-D score (21.1% vs. 15.4%; aOR 1.5 [95%CI: 1.1, 2.0]) and with a lower (worse) SF-12 MCS (-2.1 points [95%CI: -3.3, -0.9]; standardized mean difference -0.24 [95%CI: -0.37, -0.10]) at age 50, when adjusting for early-life demographic, socioeconomic, and behavioral factors.

Conclusions: Prior incarceration was associated with worse mental health at age 50 across five measured outcomes. Incarceration is a key social-structural driver of poor mental health.