The Natural History of Impaired Glucose Tolerance in the Pima Indians

Abstract
Among 384 Pima Indians with impaired glucose tolerance according to World Health Organization criteria who were followed for 1.6 to 11.5 years (median, 3.3), non-insulin-dependent diabetes mellitus (NIDDM) developed in 118 (31 percent), glucose tolerance remained impaired in 100 (26 percent), and glucose tolerance returned to normal in 166 (43 percent). The cumulative incidence of NIDDM was 25 and 61 percent at 5 and 10 years, respectively. The risk of development of diabetes was 6.3 times (95 percent confidence interval, 3.8 to 10.6) as high as in a normoglycemic control group (n = 752).