The Framingham Risk Equation underestimates risk in dialysis patients.
The Framingham Risk Equation (FRE), a standard tool for predicting CVD risk, may greatly underestimate the true rate of heart disease among dialysis patients, according to researchers.
“Practicing nephrologists should be careful when applying this risk-predicting tool,” advised lead investigator Darshan Dalal, MD, a cardiology research fellow at Johns Hopkins University in Baltimore. The FRE is based on the traditional cardiovascular risk factors such as BP, cholesterol levels, smoking, and diabetes. Although an excellent tool for patients seen by internists and cardiologists, it has not been validated in patients with end-stage renal disease (ESRD).
Dr. Dalal and his colleagues studied 4,210 ESRD patients in the Dialysis Morbidity and Mortality Study. The group included 2,110 men (mean age 52 years, 23% smokers, and 31% diabetics) and 2,100 women (mean age 55 years, 12% smokers, and 39% diabetic). The subjects had no CVD at baseline. In both groups, about 45% were Caucasian.
The researchers used the FRE to calculate the predicted incidence of a CVD event over two years of follow up. The predicted probabilities were then compared with the actual observed occurrence of CVD. For men and women aged 30-75 years, the predicted CVD risk over their average two-year follow-up was significantly lower than the actual risk across all deciles of risk.
“The Framingham Risk Equation significantly underestimates the risk for cardiovascular disease in those patients on dialysis with no prior existing heart disease,” said co-investigator Rulan Parekh, MD, associate professor of medicine and pediatrics in the department of nephrology at Johns Hopkins. “It is important that nephrologists work up all their patients and consider them at high risk for cardiovascular disease.”
Study findings suggest that new and more comprehensive risk equations are needed to assess and predict cardiovascular risk in ESRD patients.