Comparison of past versus recent physical activity in the prevention of premature death and coronary artery disease

Background People who are physically active live longer, but it is unclear whether this is because of physical activity in the distant or more recent post. Methods We assessed activity levels in 5209 men and women in the Framingham Heart Study from 1956 to 1958 and again from 1969 to 1973. We included ind ividuals who were alive and without cardiovascular disease in the period 19 69 to 1973. The primary outcome was death from all causes during the 16 yea rs after the 1969 to 1973 assessment. Secondary outcomes were incidence and mortality rate of: cardiovascular disease. We used Cox proportional hazard s regression to calculate the relative risk of being sedentary, both unadju sted and controlling for smoking, weight, systolic blood pressure, choleste rol, glucose intolerance, left ventricular hypertrophy, chronic obstructive pulmonary disease, and cancer. Results The overall 16-year mortality rate was 37% for men and 27% For wome n. When both distant and recent activity levels were included along with ma jor cardiovascular disease risk Factors, for recent activity the most activ e tertile had lower overall mortality rate than the least active tertile fo r men (risk ratio 0.58, 95% confidence interval, 0.43-0.79) and women (risk ratio 0.61, 95% confidence interval, 0.45-0.82). For distant activity ther e was no difference in overall mortality rate between the most and least ac tive tertiles either for men or for women. Adjusting for major cardiovascul ar disease risk factors had little effect on the results. Conclusions The reduction in overall mortality rates is more associated wit h recent activity than distant activity. These results suggest that for sed entary patients, it may never be tao late to begin exercising.