BARCELONA — Patients with HIV who are treated with antiretrovirals are more likely to have metabolic syndrome than are their untreated counterparts, Dr. Julian Falutz said at an international congress on prediabetes and the metabolic syndrome.
Dr Falutz and colleague Dr. Leonard Rosenthall compared several metabolic, HIV-related, and body-composition variables in two groups of HIV-positive men, one treated (172 patients) and one untreated (32 patients). Specific measurements included body mass index, waist circumference, blood pressure, trunk fat mass, fasting lipids, and glucose homeostasis markers.
Metabolic syndrome among the men in both of the groups was assessed according to the five most commonly used sets of diagnostic criteria: NCEP (National Cholesterol Education Program), WHO (World Health Organization), IDF (International Diabetes Federation), EGIR (European Group for the Study of Insulin Resistance), and ACE (American College of Endocrinology).
The researchers found a statistically significant difference in the rate of metabolic syndrome as assessed by at least one of the classification schemes between the two groups. Overall, 20% of untreated individuals had at least one classification of metabolic syndrome, compared with almost 40% of treated men. However, there were substantial discrepancies between the rates of diagnosis of metabolic syndrome of the five classification schemes among the treated group, said Dr. Falutz, director of the HIV Metabolic Clinic at McGill University, Montreal.
With the NCEP criteria, metabolic syndrome prevalence in the treated group was 24%; under the WHO classification, it was 15%. The IDF criteria pegged the prevalence at 18%, under the EGIR criteria it was 24%, and ACE identified only 4% of the men as having metabolic syndrome. These rates are similar to those in the general population, showing that “basically our patients are at similar risk for developing metabolic syndrome,” said Dr. Falutz.
However, he added, “because the different published classification schemes do not identify the same people, there is a lack of consensus on how to diagnose metabolic syndrome.”
Dr. Falutz said he believes that more work needs to be done to sort out which classification scheme is best for predicting risk of cardiovascular events by linking diagnoses of metabolic syndrome to outcomes. “You need a very large group to be able to find out if the risk of myocardial infarction is increased, compared with other classifications,” he said. “We are going to see if we can use a combination of two classification schemes to see if people actually develop a myocardial infarction.”
Although Dr. Falutz's work is focused on patients with HIV, he said the problems he had encountered with narrowing down a definition of metabolic syndrome are applicable to other patient groups, too. “We looked at metabolic syndrome in our population because it is becoming an increasing problem,” he explained.
“There are some people at higher risk, but you have to be careful when identifying them because no one classification scheme is the best, and we have to be aware of the controversy in the HIV-negative world. We may miss some people by using one [particular] scheme,” he warned.