Lifestyle factors and risk for new-onset diabetes: a population-based cohort study

Abstract

Background: Epidemiologic data on the combined influence of several lifestyle factors on diabetes risk are rare, particularly among older adults.

Objective: To examine how combinations of lifestyle risk factors relate to the 11-year risk for incident diabetes.

Design: Population-based prospective cohort study.

Setting: National Institutes of Health (NIH)-AARP Diet and Health Study.

Participants: 114,996 men and 92,483 women, aged 50 to 71 years in 1995 to 1996, without evidence of heart disease, cancer, or diabetes.

Measurements: A comprehensive survey of demographic characteristics and lifestyle factors, including dietary intake, body weight and height, physical activity, smoking, and alcohol consumption at baseline (1995 to 1996). Low-risk groups were formed by dichotomizing each lifestyle factor. Incident self-reported, physician-diagnosed diabetes was identified with a follow-up survey in 2004 to 2006.

Results: 11,031 men (9.6%) and 6969 women (7.5%) developed new-onset diabetes. For each additional lifestyle factor in the low-risk group, the odds for diabetes were 31% lower (odds ratio [OR], 0.69 [95% CI, 0.68 to 0.71]) among men and 39% lower (OR, 0.61 [CI, 0.60 to 0.63]) among women. Men and women whose diet score, physical activity level, smoking status, and alcohol use were all in the low-risk group had ORs for diabetes of 0.61 (CI, 0.56 to 0.66) and 0.43 (CI, 0.34 to 0.55), respectively. When absence of overweight or obesity was added, the respective ORs were 0.28 (CI, 0.23 to 0.34) and 0.16 (CI, 0.10 to 0.24) for men and women. Results did not differ by family history of diabetes or level of adiposity.

Limitation: The study was observational, with potential for residual confounding.

Conclusion: Lifestyle factors, when considered in combination, are associated with a substantial reduction in risk for diabetes.

Primary funding source: The NIH-AARP Diet and Health Study was supported by the Intramural Research Program of the NIH.

Figure 1

Adjusted odds ratios and 95% confidence intervals for new-onset diabetes according to number of lifestyle factors in the low-risk category stratified by sex. The P-trend for both men and women was < 0.001. The low-risk lifestyle factors included a body mass index 18.5–24.9 kg/m², never smoker or quit ≥ 10 years, top two quintiles of a diet score, alcohol use 5–29.9 g/day for men or 5–14.9 g/day for women, or participation in at least 20 minutes of physical activity ≥3–4 times/week. Adjusted for age, race/ethnicity, educational attainment, marital status, and for women, use of hormone replacement therapy.

Figure 1

Adjusted odds ratios and 95% confidence intervals for new-onset diabetes according to number of lifestyle factors in the low-risk category stratified by sex. The P-trend for both men and women was < 0.001. The low-risk lifestyle factors included a body mass index 18.5–24.9 kg/m², never smoker or quit ≥ 10 years, top two quintiles of a diet score, alcohol use 5–29.9 g/day for men or 5–14.9 g/day for women, or participation in at least 20 minutes of physical activity ≥3–4 times/week. Adjusted for age, race/ethnicity, educational attainment, marital status, and for women, use of hormone replacement therapy.