(March 11, 2011 - Insidermedicine)

Obesity type is not important while blood pressure, lipid levels, and diabetes history remain key in the prediction of first onset cardiovascular disease, according to research published online ahead of print in The Lancet.

Here are some recommendations for delivering a formal cardiovascular risk assessment, from the National Collaborating Centre for Primary Care:

•    The Framingham 1991 10-year risk equations should be used to assess risk

•    The Framingham risk equation should not be used for people who are already considered at high risk of cardiovascular disease

•    When using the risk score to inform drug treatment decisions, particularly if it is near to the threshold of 20%, consider other factors that may predispose the person to premature cardiovascular disease or factor that may not be included in calculated risk scores

Researchers representing the Emerging Risk Factors Collaboration out of the University of Cambridge used medical records from 221,934 individuals from 17 countries to calculate the hazard ratio (HR) for incident cardiovascular disease associated with body mass index (BMI), waist-to-hip ratio, and waist circumference.

After adjusting for age, sex, and smoking status, among individuals with a BMI of 20 kg/m2 or greater, BMI, waist-to-hip-ratio, and waist circumference were associated with a 23 to 27% increased risk of incident cardiovascular disease. After controlling for baseline systolic blood pressure, history of diabetes, and total HDL cholesterol, the predictive value of the three measures dropped to 7 to 12%. Adding BMI, waist circumference, or waist-to-hip ratio to a cardiovascular disease risk prediction model containing conventional risk factors did not importantly improve risk discrimination or classification of participants into 10-year risk categories.

Today’s research highlights the need for blood testing to assess cardiovascular risk in the developed world. While obesity remains an important risk factor, standard measures of obesity do not contribute to cardiovascular disease risk prediction beyond that provided by blood pressure, history of diabetes, and lipids. In addition, the study suggests that no one of these three measures of obesity has more predictive value than the others.