Glucose intolerance and 22-year stroke incidence. The Honolulu Heart Program

Area of Science:

• Epidemiology
• Cardiovascular Medicine
• Endocrinology

Background:

• Glucose intolerance and diabetes are prevalent conditions.
• Understanding their independent impact on stroke risk is crucial for public health.
• Previous studies have yielded mixed results regarding stroke subtypes.

Purpose of the Study:

• To investigate the association between glucose tolerance categories and stroke risk.
• To determine if diabetes and impaired glucose tolerance independently predict thromboembolic and hemorrhagic stroke.
• To assess the influence of other cardiovascular risk factors on this relationship.

Main Methods:

• Prospective cohort study of 7549 Japanese-American men (aged 45-68).
• Glucose tolerance classified into four categories based on oral glucose tolerance test and diabetes history.
• Stroke incidence (thromboembolic, hemorrhagic) ascertained over 22 years using Cox proportional hazards models.

Main Results:

• Incidence of thromboembolic stroke, but not hemorrhagic stroke, increased with worsening glucose tolerance.
• Significantly elevated relative risks for thromboembolic stroke were found in "high-normal" glucose, "asymptomatic high" glucose, and "known diabetes" groups.
• Adjusted relative risks remained significant for "asymptomatic high" (1.43) and "known diabetes" (2.45) groups, independent of other risk factors.

Conclusions:

• Diabetes and elevated glucose levels are associated with an increased risk of thromboembolic stroke.
• This association is largely independent of other major cardiovascular disease risk factors.
• The increased risk is evident across different age groups and in both hypertensive and nonhypertensive individuals.