Regular physical activity can reduce risk of cardiovascular mortality among patients with type 2 diabetes whether or not they have other known cardiovascular risk factors.
Thus, the American Diabetes Association, the National Cholesterol Education Program Export Panel and the International Diabetes Federation (European Region) have recommended physical activity for the primary and second prevention of cardiovascular complications among patients with type 2 diabetes (1-3).
There is good evidence that regular physical activity reduces the risk of cardiovascular disease in the general population (4, 5).
Recently, several studies have assessed the association between physical activity or physical fitness and the risk of cardiovascular mortality among patients with type 2 diabetes (6-12).
The results from the Aerobic Center Longitudinal Study (6), the Nurses’ Health Study (7), the Whitehall Study (8), the National Health Interview Survey (9), and the Health Professionals’ Follow-up Study (10) have indicated that regular leisure-time physical activity is associated with reduced cardiovascular and total mortality among patients with diabetes or impaired glucose tolerance. Walking has a similar inverse association with the risk of cardiovascular and total mortality to that of vigorous leisure-time physical activity (7-10).
In the Aerobic Center Longitudinal Study, physical fitness had a strong and independent inverse association with total mortality in men with diabetes, and this association was seen in all body mass index and body fatness group (6, 11).
The analyses from the FINMONICA study also evaluated whether other types of physical activities, such as occupational and daily commuting physical activity on foot or by bicycle, are related to reduced cardiovascular mortality among diabetic patients (12).
We reviewed data on 3316 patients aged 25 to 74 with history of type 2 diabetes who participated in surveys of randomly selected samples from the Finnish population conducted between 1972 and 1997. The data included questionnaires on the level of physical activity on the job; on the way to and from work; and during their leisure time.
During an average follow-up of 18.4 years, 1410 of the subjects died, 903 (64%) from cardiovascular disease. After adjusting for age, gender, body mass index, systolic blood pressure, total cholesterol, smoking and the other two categories of physical activity, we found that moderately active work was associated with a 9% reduction in cardiovascular mortality and active work was associated with a 40% reduction (Table).
High level of leisure-time physical activity was associated with a 33% drop and moderate activity was linked to a 17% drop in cardiovascular mortality compared with the most sedentary group. Daily walking or cycling to and from work decreased cardiovascular mortality, but this relation was no longer significant after additional adjustment for occupational and leisure-time physical activity.
We further merged and regrouped these three types of physical activity into three categories: low was defined as subjects who reported light levels of occupational, commuting (<1 minute) and leisure-time physical activity; moderate was defined as subjects who reported only one of the all three types of moderate to high physical activity; high was defined as subjects who reported two or three types of moderate to high physical activity.
We found that those who were moderately active reduced their risk of dying from cardiovascular disease by 39 percent, while those who were highly active reduced the risk by 48 percent (13). The protective benefits of physical activity were consistent regardless of body mass index, blood pressure or cholesterol levels or whether or not the person smoked (13).