Interaction Between Immigration, Physical Activity, Mental Health, and All-Cause Mortality Among US Adults.

Abstract

Immigration, physical activity, and mental health have been reported to affect mortality risk. Nonimmigrants, people who lack physical activity, and those with mental health conditions are at a higher mortality risk. However, the joint association of immigration, physical activity, and mental health with mortality risk is unclear. To estimate the interaction among immigration status, physical activity status, and serious psychological distress (SPD) and its association with all-cause mortality risk among US adults during a 22-year follow-up. In this national cohort study, public-use data from the 1998-2018 National Health Interview Surveys were linked to the prospective 2018-2019 National Death Index data. This population-based study included a nationally representative sample of civilian noninstitutionalized US adults 18 years or older. Data were collected from January 1, 1998, to December 31, 2019, and analyzed from August 10, 2023, to July 15, 2025. Immigration status (immigrant or nonimmigrant), physical activity (inactive or insufficiently active or physically active), and SPD (determined using the 6-item Kessler Psychological Distress Scale, with a total score of ≥13 indicating SPD). All-cause mortality status (deceased or alive) constituted the primary outcome. Cox proportional hazards regression models were used to examine mortality risk associated with the exposures. A total of 587 931 adults were included in the analysis. Weighted proportions included 37.2% (95% CI, 37.0%-37.4%) aged 35 to 54 years, 51.9% (95% CI, 51.8%-52.1%) female, 83.8% (95% CI, 83.5%-84.1%) nonimmigrant, 53.7% (95% CI, 53.4%-54.0%) with insufficient physical activity, and 96.8% (95% CI, 96.7%-96.8%) with no SPD. The Cox proportional hazards regression analysis showed a significant 3-way interaction among immigration status, physical activity, and SPD (Wald F4 = 14.12; P < .001). There was a lower expected mortality risk among immigrants with SPD who engaged in physical activity (HR, 6.08; 95% CI, 3.97-8.19) compared with immigrants with SPD who lacked physical activity (HR, 10.50; 95% CI, 8.93-12.08) as well as nonimmigrants who lacked physical activity regardless of SPD status (No SPD HR, 13.03; 95% CI, 12.16-13.90 and SPD HR, 14.13; 95% CI, 13.04-15.21) or who engaged in physical activity with SPD (HR, 11.44; 95% CI, 9.89-12.99). There were no significant differences between immigrants without SPD who engaged in physical activity or immigrants without SPD who lacked physical activity and nonimmigrants who engaged in physical activity without SPD. In this population-based cohort study, the results showed a joint association of immigration status, physical activity, and SPD with all-cause mortality. Immigrants and especially nonimmigrants might benefit from tailored behavioral health interventions aimed at increasing physical activity and reducing SPD to mitigate disparities in mortality risk.