Physical Fitness Predicts Survival in Men with Type 2 Diabetes
posted 12/10/03
Men with Type 2 diabetes are two times more likely to die then those that are considered fit.

Type 2 diabetes mellitus, also known as adult-onset diabetes, is a common disease that interferes with the body’s ability to store foods, resulting in high blood levels of sugar. Over time, high blood sugar levels can lead to such complications as blindness, kidney failure, and heart disease. Exercise helps to control blood sugar, lower blood pressure and cholesterol, and prevent weight gain. It is not known, however, whether physical fitness actually improves survival for patients with type 2 diabetes.

To find out whether persons with type 2 diabetes who are physically active live longer than those who are physically inactive. The study included1263 men with type 2 diabetes who received a thorough medical examination between 1970 and 1993; their average age was 50 years. Men who took insulin injections to control their diabetes were not included.

Study participants completed a medical history, questions about health and exercise habits, a physical examination, blood tests, and electrocardiography. Study participants also took a maximal exercise test. This test shows how hard a person can exercise on a treadmill and is a measure of physical fitness. The researchers classified the 20% of the men who did worst on the exercise test as "low fit" and all of the other men as "fit." The researchers used the National Death Index, a database that lists all deaths in the United States, to see which men had died by December 31, 1994. They then looked for associations among exercise habits, physical fitness, and death.

The researchers found that one hundred eighty of the men had died by December 31, 1994. After accounting for other risk factors, such as smoking and age, men in the "low fit" group were two times more likely to have died than men who were "fit."

There were limitations to the study which included only men, more than 92% of whom were white, so it is uncertain whether these findings would apply to women or persons of other ethnic backgrounds. It is also uncertain whether the findings would be the same in persons who needed to take insulin to control their diabetes. While the results suggest that people with type 2 diabetes may live longer if they start to exercise, only a study that randomly assigns people to exercise or no exercise would prove this.

It was concluded from the study that patients with type 2 diabetes should participate in regular exercise and improve their physical fitness. This may help them live longer, in addition to helping control their blood sugar levels.

Source: Diabetes In Control.com: "Low Cardiorespiratory Fitness and Physical Inactivity as Predictors of Mortality in Men with Type 2 Diabetes." Annals of Internal Medicine (volume 132, pages 605-611).