Physical activity has powerful life-saving effects for people with serious chronic conditions, according to a study by scientists at Harvard Pilgrim Health Care Institute. In research published online October 1 in BMJ, a team of investigators led by Huseyin Naci, an HMS visiting fellow in population medicine at the Institute and a graduate student at the London School of Economics, showed that exercise is potentially as effective as many drug interventions for patients with cardiovascular disease and other chronic conditions. The researchers say the study is the first to assess the comparative benefits of drugs and exercise for reducing mortality in a range of illnesses.
“We were surprised to find exercise showed such powerful life-saving effects for people with serious chronic conditions,” says Naci, “and that so little is known about the potential benefits of physical activity in so many other illnesses.”
Four conditions in which the effects of exercise on reducing mortality had been studied were prevention of severe illness in patients with coronary heart disease, rehabilitation from stroke, treatment of heart failure, and prevention of diabetes.
For the study, the researchers analyzed the results of 305 randomized controlled trials involving 339,274 individuals and found no statistically detectable differences between exercise and drug interventions for secondary prevention of heart disease and prevention of diabetes. Among stroke patients, exercise was more effective than drug treatment, while in congestive heart failure, diuretic drugs were more effective than all other therapies, including exercise.
The authors point out that the amount of trial evidence on the mortality benefits of exercise is considerably smaller than that on the benefits of drugs, and that this may have had an impact on their results. Of the nearly 340,000 cases analyzed, fewer than 15,000 included exercise-based interventions.
In the United States, 80 percent of people 18 and older failed to meet the guidelines for aerobic and muscle-strengthening physical activity in 2011, according to the Centers for Disease Control and Prevention.