BACKGROUND

Although studies have demonstrated that both lifestyles and subjective well-being (SWB) are associated with mortality risk, the joint effects of a healthy lifestyle and SWB on the risk of mortality are unclear. This study aimed to explore the combined impact of lifestyles and SWB on total mortality among the older Chinese population.

METHODS

Data were obtained from the Chinese Longitudinal Healthy Longevity Survey conducted from 2002 to 2018. A total of 13,282 participants aged ≥ 65 years were included. SWB was measured by an eight-item tool covering life satisfaction, optimism, conscientiousness, anxiety, loneliness, personal control, feeling useless, and happiness. A total healthy lifestyle score was calculated by summing across five lifestyle factors (smoking, drinking, exercise, dietary diversity and body mass index), ranging from 0 to 5, and was categorized into the following groups: healthy (4-5 points), intermediate (2-3 points) and unhealthy (0-1 point). Cox proportional regression analyses were carried out adjusting for demographic characteristics and other potential confounders.

RESULTS

In total, 8549 (64.4%) deaths were reported during the follow-up period. Compared with the higher healthy lifestyle score, the hazard ratios (HRs) for all-cause mortality for the intermediate and unhealthy lifestyle scores were 1.11 (1.04-1.17) and 1.17 (1.09-1.26), respectively, independent of SWB. A similar relationship between SWB and total mortality was observed, independent of lifestyle factors. The participants who had worse SWB experienced a 1.19 (1.14-1.25) higher risk of total mortality in comparison with those who had better SWB after adjusting for lifestyles. Combinations of unhealthy lifestyle scores and poor SWB were associated with an increased risk of total mortality, and the highest risk was found among participants with a healthy lifestyle score of 0-1 and worse SWB (HR = 1.41, 95% CI = 1.28-1.55).

CONCLUSIONS

A stronger risk of total mortality was found when worse SWB and unhealthy lifestyle occurred together, suggesting that a comprehensive approach to healthy lifestyle and SWB might be a potential strategy to improve longevity.