Insulin Resistance Increases Heart Disease Risk in Women
Heart disease and insulin resistance are linked, but the latter does not need to be accounted for in heart risk calculations.
Insulin resistance occurs when the body produces insulin but fails to use it correctly, leading to high blood sugar levels. Without treatment or lifestyle changes, insulin resistance often leads to type 2 diabetes—a major risk factor for heart disease.
Since insulin resistance is closely linked to heart disease, researchers wondered if we should consider this condition when calculating cardiovascular risk. Currently, traditional risk factors like age, blood pressure and weight are used to determine whether an individual is at low, intermediate or high risk for developing heart disease. It’s important that risk estimations are as accurate as possible, as they help identify patients who should take extra steps to minimize risk of heart disease and life-threatening heart events.
According to a study published in the American Heart Association journal Circulation, researchers used data from the Women’s Health Initiative Biomarkers studies to assess the relationship between insulin resistance and risk for heart disease. Between 1992 and 1998, more than 15,200 postmenopausal women—all between 50 and 79 years old and free of heart disease and diabetes—enrolled in the study. After ten years, 6% of women developed heart disease or suffered major heart events like heart attack and stroke. Researchers found that women with insulin resistance had significantly higher risk of heart disease than those with normal blood sugar, even after taking into account factors like age and race. However, adding insulin resistance to traditional estimations of cardiovascular risk did not change women’s risk classifications. So whether or not women had insulin resistance did not change whether they were at low, intermediate or high risk for heart disease.
Study findings suggest that not only does insulin resistance increase risk for type 2 diabetes, it significantly increases risk for heart disease, heart attack and stroke. Since most people with insulin resistance don’t know they have it, testing blood sugar is important to identify patients at risk for both diabetes and heart disease. However, this study suggests that it’s unnecessary to take insulin resistance into account when estimating cardiovascular risk, since current calculations are precise.
Questions for You to Consider
- What is a cardiovascular risk estimate?
- To identify patients at increased risk for heart disease, doctors use tools to estimate a person’s short and long-term risk of heart disease. These tools take into account factors closely related to cardiovascular risk, such as age, sex, cholesterol and smoking status, to estimate risk of developing heart disease in a given time period. Most estimates calculate short-term risk (risk of developing heart disease in the next 10 years) or long-term risk (risk of developing heart disease in an entire lifetime).