Importance Length of custody is a mechanism by which carceral systems can worsen health. However, there are fewer studies examining US immigration detention, in large part because US immigration detention is largely privately operated and opaque by design. Objectives To examine the association between duration spent in US immigration detention with subsequent health outcomes. Design, Setting, and Participants This cross-sectional study used a referral sample of recently detained immigrants who were released from Immigrations and Customs Enforcement (ICE) under a series of court orders in 2020 and 2021. Data were analyzed from June 2023 to October 2024. Exposure Detention duration less than 6 months vs 6 months or longer. Main Outcomes and Measures We used multivariable regression analysis to assess the association of detention duration and several variables: (1) self-rated health, (2) mental illness (Kessler 6-item psychological distress scale), and (3) posttraumatic stress disorder (PTSD) (Primary Care-PTSD-5 Screen). We then calculated the likelihood of experiencing each outcome, controlling for covariates. As a robustness check, we conducted sensitivity analyses with detention duration as a continuous measure. Results The study included 200 respondents (mean [SD] age, 40.3 [10.1] years; 175 male [87.5%]; 149 Hispanic or Latino ethnicity [74.5%]). Results revealed a high prevalence of poor self-rated health, mental illness, and PTSD for all respondents, but especially among those who had been detained for 6 months or longer, who had significantly higher likelihood of poor or fair self-rated health (49.1% [95% CI, 40.5%-57.6%] vs 30.4% [95% CI, 21.8%-39.1%]; P < .001), mental illness (37.0% [95% CI, 28.2%-45.8%] vs 20.7% [95% CI, 12.6%-28.7%]; P < .001), and PTSD (59.3% [95% CI, 50.3%-68.3%] vs 34.8% [95% CI, 25.3%-44.3%]; P < .001). Sensitivity analysis confirmed the general robustness of these findings, with longer detention duration significantly associated with mental illness (OR, 1.11 [95% CI, 1.02-1.20]; P = .01) and PTSD (OR, 1.11 [95% CI, 1.03-1.20]; P = .005) in our adjusted models. Conclusions and Relevance In this cross-sectional study, detained immigrants experienced a high prevalence of poor health, mental illness, and PTSD, with detention periods of 6 months or more associated with higher rates compared with those detained less than 6 months. Duration of custody is one mechanism by which immigration detention might be a catalyst for worsening health.
