GLUCOSE-INTOLERANCE AND 22-YEAR STROKE INCIDENCE - THE HONOLULU HEARTPROGRAM

Background and Purpose This study was conducted to determine whether g lucose intolerance and diabetes increase the risk of thromboembolic, h emorrhagic, and total stroke independent of other risk factors. Method s Among 7549 Japanese-American men aged 45 to 68 years and free of cor onary heart disease and stroke during 1965 to 1968, history of diabete s, diabetic medication, and nonfasting glucose 1 hour after a 50-g loa d were used to classify subjects into four glucose tolerance categorie s. Incidence of stroke over 22 years was ascertained using comprehensi ve hospital-based surveillance. Age- and risk factor-adjusted relative risks of stroke were determined using a Cox proportional hazards mode l. Results A total of 374 thromboembolic, 128 hemorrhagic, and 36 type -unknown strokes occurred. Incidence of thromboembolic but not hemorrh agic stroke increased with worsening glucose tolerance category. Compa red with the ''low-normal'' (glucose <151 mg/dL) group, subjects in th e ''high-normal'' (151 to 224 mg/dL), ''asymptomatic high'' (greater t han or equal to 225 mg/dL), and ''known diabetes'' groups all had sign ificantly elevated age-adjusted relative risks of thromboembolic strok e. After adjustment for other risk factors, relative risks remained si gnificantly elevated for the asymptomatic high and known diabetes grou ps (1.43 and 2.45; 95% confidence intervals, 1.00 to 2.04 and 1.73 to 3.47, respectively). Associations were the same in hypertensive and no nhypertensive subjects and similar but slightly stronger in younger (a ged 45 to 54 years) than in older (aged 55 to 68 years) men. Conclusio ns Subjects with diabetes and elevated glucose appear to be at increas ed risk of thromboembolic but not hemorrhagic stroke. These associatio ns were largely independent of other cardiovascular disease risk facto rs. Excess risk is apparent in older as well as younger diabetic indiv iduals and in hypertensive and nonhypertensive subjects with diabetes.