It is being sponsored by the World Federation of Neurology and the Bowman Gray School of Medicine of Wake Forest University. The researchers used ultrasound to measure the extent of atherosclerosis in a test population of 1,625 people. After controlling for such factors as diet, cholesterol levels, age and other factors, the research showed that a moderate difference in insulin resistance had as large an impact on atherosclerosis in whites and Hispanics as other major risk factors, such as hypertension. However, no such association was present in African Americans. Howard said there is no clear reason why insulin resistance is a risk factor in whites and Hispanics, but not African Americans, especially given African Americans' greater propensity for strokes.
Science sometimes raises more questions than it can answer.
Because of the high correlation the study found between diabetes and insulin resistance, the research is especially significant to the estimated 16 million Americans who have diabetes. Howard said he suspects that one reason many people who are insulin resistant have diabetes is the tremendous amount of extra insulin that insulin-resistant people must produce to process the glucose in their blood. Currently there is no easy way to test for insulin resistance, Howard said. Once detected, doctors could prescribe drugs already on the market that treat insulin resistance. The study marks an expansion in the use of ultrasound to detect disease before symptoms appear.