Long-term impact of physical activity on mortality in adults with multimorbidity: a 12-year cohort longitudinal study from the Survey on Health, Aging, and Retirement in Europe

<p dir="ltr">Background: While physical activity (PA) is known to reduce mortality in the general population, this relationship in individuals with multimorbidity (≥ 2 chronic conditions) is unclear. This longitudinal study aimed to investigate whether there is a long-term association between PA levels and mortality rates over a 12-year period in adults with multimorbidity. <p dir="ltr">Methods: Data were obtained from eight waves of the Survey of Health, Ageing and Retirement in Europe (SHARE), from 28 European countries. PA levels were self-reported via computer-assisted personal interviews. Mortality during the follow-up period was assessed using data obtained from caregivers through end-of-life interview. Multimorbidity was identified based on the presence of two or more 15 self-reported chronic diseases/conditions. Cox's regression analysis, adjusted for potential confounders, was used to assess the association between PA level and mortality. p-values were calculated using the Jonckheere–Terpstra test for continuous variables and the Mantel–Haenszel Chi-square test for categorical variables, stratified by PA level. <p dir="ltr">Results: The study included 9216 participants with multimorbidity (mean age 69 ± 10.1 years; 58.7% were women). Among those with multimorbidity, individuals with high PA level were significantly younger, more frequently men, less impaired in activities of daily living, less educated and less frequently obese than those with very low level of PA (p < 0.0001 for all comparisons). Over the 12 years of follow-up, mortality incidence was three times higher in individuals with multimorbidity and very low PA levels than those with multimorbidity and high levels of PA. After adjusting for confounders, the risk of mortality was significantly lower for participants with moderately low PA levels (HR = 0.64; 95% CI: 0.59–0.71; p < 0.0001), moderately high PA levels (HR = 0.53; 95% CI: 0.47–0.60; p < 0.0001) and high PA levels (HR = 0.49; 95% CI: 0.43–0.55; p < 0.0001) compared to those with very low PA levels. <p dir="ltr">Conclusions: Findings from the present study suggest that people with multimorbidity who had lower levels of PA were three times more likely to die prematurely after 12 years than adults with multimorbidity and higher levels of PA at baseline. These findings underscore the importance of promoting physical activity in adults with multimorbidity to reduce the risk of premature mortality. Future longitudinal research is required to confirm/refute our findings. Further, intervention studies are needed to understand whether increasing levels of physical activity in this population subsequently reduces mortality risk.