Combined healthy lifestyle behaviors and all-cause mortality risk in middle-aged and older US adults: A longitudinal cohort study

Background: While various lifestyle behaviors separately or partly have been shown to be associated with health outcomes, including a multitude of diseases and death, none of the earlier research has comprehensively investigated the combined impact of modified lifestyle behaviors. This longitudinal study investigated the association between a composite of healthy lifestyle behaviors and all-cause mortality in middle-aged and older Americans. Methods: We utilized data from the National Health and Nutrition Examination Survey from 2007 to 2018, as well as relevant mortality data, applying the Healthy Lifestyle Score1 (HLS) index to assess healthy lifestyle behaviors, defined by no smoking, moderate alcohol, appropriate sleep, a balanced diet, adequate physical activity, and limited sedentary time. Weighted multivariate Cox proportional hazards analyses were applied to investigate the associations between these lifestyle practices and overall mortality, followed by stratified analyses to explore potential effect modifications by subgroups. Results: This study included 5448 participants, categorized into unfavorable (28%), intermediate (56%), and favorable (16%) HLS groups. During a median 103-month follow-up, 388 participants died. Cox regression revealed that individuals with favorable lifestyles had a reduced likelihood of death than those with unfavorable lifestyles (HR = 0.49, 95% CI: 0.34-0.70). There was a linear negative relationship established between HLS and the likelihood of all-cause death (p for non-linearity = 0.0512). Conclusion: Adherence to a composite of healthy habits is linearly and substantially related to decreasing the likelihood of all-cause mortality among the elderly in the U.S., highlighting the substantial benefits of maintaining these behaviors for longevity and health.