Insulineresistentie verhoogt risico op stroke bij non-diabeten
Insulin resistance ups stroke risk in nondiabetic adults
October 14, 2010
"These findings, if confirmed in other cohorts, may open new treatment opportunities with direct effect on reducing the atherosclerotic process," first author Dr Tatjana Rundek (University of Miami Miller School of Medicine, FL) noted.
The researchers found an association between insulin resistance and ischemic stroke in 1509 nondiabetic participants in the ongoing Northern Manhattan Study. While the mean HOMA-IR index was 2.3, subjects in the top quartile (Q4) had a HOMA-IR value of at least 2.8; 26.3% of women and 22.6% of men fell into this group.
Over an average of 8.5 years of follow-up, 180 individuals experienced one or more vascular events. There were 46 cases of fatal or nonfatal ischemic stroke, 45 cases of fatal or nonfatal MI, and 121 vascular deaths.
In a multivariate adjusted model, HOMA-IR Q4 significantly predicted the risk of ischemic stroke, but not MI or other vascular events, compared with those in the lower three quartiles, the researchers report.
Risk of stroke and vascular events with HOMA Q4 vs Q1-Q3
||Multivariate-adjusted hazard ratio
|Combined vascular events
The researchers say there are several possible reasons for the stronger effect of insulin resistance on the risk of ischemic stroke than on the risk of MI. It may be because factors associated with insulin resistance, such as hypertension, hypertriglyceridemia, and low HDL cholesterol, are more important risk factors for stroke than MI or because individuals with a history of MI were excluded from the study.
Insulin resistance "may be a novel therapeutic target for stroke prevention," the investigators conclude, although Rundek cautioned that lifestyle changes (weight control, exercise, and healthy diet) and control of blood pressure, lipids, and glucose are still gold-standard treatments to prevent diabetes, stroke, and other consequences of atherosclerosis.
"In individuals with insulin resistance, who now we know have almost a threefold increased risk of stroke over those without insulin resistance, physicians may decide to be more aggressive with these therapies," she said.