Increased cardiorespiratory fitness over 20 years reduces risk for prediabetes, diabetes
An ongoing, higher level of cardiorespiratory fitness over 2 decades was shown to reduce the risk for developing prediabetes and type 2 diabetes, even after adjusting for changes in BMI, according to recent study findings.
“Exercise is well documented to improve fitness,” Lisa S. Chow, MD, MS, associate professor of medicine in the division of diabetes, endocrinology and metabolism at the University of Minnesota, told Endocrine Today. “Identifying mechanisms to deliver exercise in an acceptable and sustainable way to the general population remains critically important. Likewise, since the individual response to a fixed exercise exposure may be quite variable, it is important to identify the physiological mechanisms driving the benefits of exercise.”
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Lisa S. Chow
Chow and colleagues analyzed data from 4,373 black and white adults free from prediabetes or type 2 diabetes at baseline participating in the Coronary Artery Risk Development in Young Adults (CARDIA) study in 1985-1986 (mean baseline age, 24 years). Follow-up exams, including assessment for development of prediabetes or type 2 diabetes, were conducted at years 2, 5, 7, 10, 15, 20 and 25. Participants completed a treadmill test to assess cardiorespiratory fitness at baseline, years 7 and 20. Participants self-reported physical activity via questionnaires.
By year 25, 44.5% of the cohort developed prediabetes (n = 1,941); 11.5% developed type 2 diabetes (n = 505). After adjusting for the time-varying aspect of BMI, researchers found that higher cardiorespiratory fitness (per 1 metabolic equivalent increment) was associated with lower risk for developing incident prediabetes or type 2 diabetes (0.99898; 95% CI, 0.99861-0.9994). Results persisted after adjusting for lifestyle factors including smoking, energy intake, alcohol intake and education, as well as blood pressure, HDL and LDL (0.99872; 95% CI, 0.9984-0.99904). When using treadmill exercise testing to measure cardiorespiratory fitness, an 8% to 11% higher fitness level reduced the risk for developing prediabetes or type 2 diabetes by 0.1%, according to researchers.
Participants who developed diabetes or prediabetes by year 25 had lower cardiorespiratory fitness at baseline, year 7 and year 20, lower HDL and were less likely to increase their cardiorespiratory fitness over 20 years vs. those who did not develop prediabetes or type 2 diabetes. Researchers found no between-group differences in educational level or self-reported physical activity.
“Even when considering BMI changes, ongoing fitness is important to reduce the development of prediabetes and diabetes,” Chow said. – by Regina Schaffer
For more information:
Lisa S. Chow, MD, MS, can be reached at the division of diabetes, endocrinology and metabolism, department of medicine, University of Minnesota, MMC 101, 420 Delaware St. SE, Minneapolis, MN, 55455; email: chow0007@umn.edu.
Disclosure: The researchers report no relevant financial disclosures.