Prevalence of diabetes and impaired glucose tolerance in elderly subjects and their association with obesity and family history of diabetes.

The goal of this study was to investigate the prevalence of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) in elderly subjects and their association with obesity, central obesity, and a family history of diabetes. A representative population sample of 1300 subjects (471 men, 829 women) aged 65-74 yr participated in the study. The participation rate was 71%. The prevalence rates of previously and newly diagnosed NIDDM and IGT, based on a history of diabetes and an oral glucose tolerance test, were 8.7, 7.0, and 17.8% in men and 11.7, 7.1, and 19.1% in women. Thus, 33.8% of men and 37.9% of women had abnormal glucose tolerance according to World Health Organization criteria. Obesity (body mass index greater than or equal to 27 kg/m2 in men and greater than or equal to 25 kg/m2 in women) and central obesity (waist-hip ratio greater than or equal to 0.98 in men and greater than or equal to 0.89 in women) doubled the prevalence of IGT or NIDDM. The combination of obesity and a family history of diabetes was associated with a more marked increase in the prevalence of IGT or NIDDM in men than in women. Simultaneous presence of obesity, central obesity, and a family history of diabetes was associated with a threefold increase in the prevalence of IGT or NIDDM (65.4 vs. 24.1% in men, 52.8 vs. 19.6% in women, P less than 0.001). The major risk factors for NIDDM, e.g., obesity, central fat distribution, and a family history of diabetes, explained 10% of the variance in 2-h glucose values in multiple regression analysis. In conclusion, the prevalence of IGT and NIDDM was high in elderly subjects. Although obesity, central fat distribution, and a family history of diabetes were significantly associated with the increased prevalence of IGT or NIDDM, they explained only a minor proportion of the variance in 2-h glucose values.