Using the Framingham Heart Study data (United States, 1948-1978), the authors examined the association of blood glucose with 2-year all-cause, cardiovascular, and noncardiovascular mortality in subjects with documented cardiovascular disease. After adjustment for systolic blood pressure, cholesterol, body mass index, cigarette smoking, and use of antihypertensive agents, they found that glucose was a strong, independent predictor of mortality. However, the relations for men and women were qualitatively different. For men, adjusted mortality risk increased very rapidly through the normal range (from 4.12% at 3.89 mmol/liter (70 mg/dl) to 12.26% at 5.55 mmol/liter (100 mg/dl)) and was flat at 12.26% thereafter. For women, risk was flat at 3.65% through the normal range and then increased rapidly, reaching 8.34% at 6.99 mmol/liter (126 mg/d), but increased much more slowly thereafter. Exactly analogous relations held for cardiovascular mortality. For men and women combined, noncardiovascular mortality increased from 1.82% at 3.89 mmol/liter to 2.06% at 5.55 mmol/liter to 2.29% at 6.99 mmol/liter (p for trend = 0.009). These findings suggest that although 5.55 mmol/liter (normal) may be a useful mortality risk division (albeit with different implications for the two sexes), 6.99 mmol/liter (diabetic) is not, especially for men.