Physical Activity and the Effect of Multimorbidity on All-cause Mortality in Older Adults

Abstract Objective To examine the stratified and joint associations of physical activity (PA) and the number of chronic conditions on long-term all-cause mortality. Patients and Methods We used data from a cohort of 3967 individuals representative of the noninstitutionalized population 60 years and older in Spain (2000/2001). Information on self-reported PA (inactive, occasionally, monthly, weekly) and 11 chronic conditions diagnosed by a physician and reported by the study participants were recorded. Associations are summarized using hazard ratios (HRs) and Cox regression, after adjustment for covariates. Results At baseline, 43.2%, 37.5%, 14.4%, and 4.9% of participants had 0, 1, 2, and 3 or more chronic conditions, respectively. Mean follow-up was 8.9 years (median, 10.8 years; range, 0.02-11.28 years), with 1483 deaths. The HRs (95% CIs) for all-cause mortality in participants with 1, 2, and 3 or more chronic conditions compared with those with none were 1.26 (1.05-1.39), 1.78 (1.51-2.09), and 2.27 (1.79-2.86), respectively. Being physically active (ie, doing any PA) was associated with a mortality reduction (95% CI) of 30% (14%-43%), 33% (18%-45%), 35% (16%-50%), and 47% (18%-66%) in participants with 0, 1, 2, and 3 or more chronic conditions, respectively. Compared with those with 0 chronic conditions who were physically active, participants with 2 (HR=2.63; 95% CI, 2.09-3.31) and 3 or more (HR=3.26; 95% CI, 2.42-4.38) chronic conditions who were physically inactive had the highest mortality risk. Conclusion Physical activity is associated with a reduction in increased risk of death associated with multimorbidity (ie, coexistence of ≥2 chronic conditions) in older individuals.