Older adults who spend more time on leisure-time physical activity — even those adults who have been sedentary throughout adulthood — may experience a lower risk of mortality, according to the results of a study recently published in JAMA Network Open. Already-active adults should be encouraged to maintain activity levels through older age, whereas inactive adults in midlife should be encouraged to prioritize leisure-time physical activity.
This prospective cohort study included 315,059 adults (58.2% men; aged 50 to 71 years) within the dataset of the National Institutes of Health-AARP Diet and Health Study. Participants lived in Pennsylvania, North Carolina, New Jersey, Louisiana, Florida, California, as well as in Detroit, Michigan and Atlanta, Georgia. Leisure-time physical activity was self-reported in weekly hours at baseline with stratification by age. The data were used in combination with mortality data from the National Death Index through the end of 2011, with cause of death classified as cardiovascular disease, cancer, or all-cause. The primary outcome of the study was mortality. Sensitivity analyses of hazard ratios were conducted with adjustments/exclusions for baseline disease characteristics and early death.
Among the study’s population, 71,377 participants died due to all-cause mortality; 22,219 died from cardiovascular disease, and 16,388 died from to cancer. There were 10 trajectories of leisure-time physical activity identified, which fit into 3 categories: high and maintained over time (56.1%), increased over time (13.1%), or decreased over time (30.8%). Those who maintained high physical activity over time were at the lowest risk for mortality, with a hazard ratio [HR] of 0.64 (95% CI, 0.60-0.68) for all-cause mortality, 0.58 (95% CI, 0.53-0.64) for cardiovascular disease-related mortality, and 0.86 (95% CI, 0.77-0.97) for cancer-related mortality, compared with those who were inactive throughout adulthood. Those who maintained low activity levels over time of 1 hour per week had weaker HRs (0.84; 95% CI, 0.81-0.87). However, those who increased leisure-time physical activity between the ages of 40 and 61 after an inactive adulthood also had lower risks for mortality (HR, 0.65; 95% CI, 0.62-0.68 for all-cause; HR, 0.57; 95% CI, 0.53-0.61 for cardiovascular disease; and HR, 0.84; 95% CI, 0.77-0.92 for cancer).
The researchers concluded that “[increasing] [leisure-time physical activity] later in adulthood was associated with mortality benefits that were similar to those associated with maintaining higher levels of [leisure-time physical activity] across the adult life course. Our findings suggest that it is not too late for adults to become active. These findings are particularly informative for health care professionals advising individuals who have been physically inactive throughout much of their adulthood that substantial health benefits can still be gained by improving their physical activity habits.”
Saint-Maurice PF, Coughlan D, Kelly SP, et al. Association of leisure-time physical activity across the adult life course with all-cause and cause-specific mortality. JAMA Netw Open. 2019;2(3):e190355