Associations of baseline one-hour postload plasma glucose with 22-year coronary heart disease, stroke, cardiovascular diseases, and all cause mortality were assessed in five age-specific cohorts of nondiabetic men and women from the Chicago Heart Association Detection Project in Industry: 10,269 men ages 18-39 years; 7993 men ages 40-59 years; 1240 men ages 60-74 years; 6319 women ages 40-59 years; and 932 women ages 60-74 years. Plasma glucose was determined one hour after a 50-gram oral glucose load. Cox regression analyses were used to control for age and other covariates. Generally, higher glucose was significantly associated with mortality from coronary heart disease, stroke, cardiovascular diseases, and all cause mortality in men and women. This large longitudinal study provides evidence that one-hour postload plasma glucose in the absence of clinical diabetes at baseline apparently is an independent risk factor for fatal coronary heart disease and stroke in middle-aged and older nondiabetic men and women, and also for cardiovascular diseases and for all cause mortality.