A longitudinal study of lifestyle behaviours in emerging adulthood and risk for symptoms of depression, anxiety, and stress

Background: Little research has examined how lifestyle behaviours cluster together to contribute to mental health outcomes. The current study aimed to identify latent classes of emerging adult lifestyle behaviours (diet, physical activity, sedentary time, smoking, alcohol, cannabis, and other drug use) at age 20 years and their associations with depression, anxiety, and stress symptoms at age 22 and 27 years. Methods: Participants were 616 emerging adults enrolled in the Raine Study. Lifestyle classes at baseline were identified using latent class analysis. Longitudinal associations between latent class membership and risk of depression, anxiety, and stress symptoms were examined using logistic regression models. Results: Three lifestyle classes were identified: Class 1 (healthier pattern, n = 399 [64.8 %]), Class 2 (predomi-nantly female, high substance-use, low physical activity pattern, n = 121 [19.6 %]), and Class 3 (predominantly male, high substance-use, poor diet pattern, n = 96 [15.6 %]). Following adjustment, Class 2 were at a higher risk of depression, anxiety, and stress symptoms at age 22 years, and a higher risk of anxiety and stress symptoms at age 27 years, compared to Class 1. Limitations: This study was limited by reliance on self-report data, lack of available indicators for parental so-cioeconomic status, and some measurement inconsistencies across variables. Adherence to lifestyle clusters over time was not assessed. Conclusions: Latent classes of lifestyle behaviours were identified among emerging adults, and differences in mental health outcomes were found among the classes at two prospective time points. Future research and prevention strategies for common mental disorders should target emerging adults and focus on lifestyle patterns.