By Liz Highleyman

The metabolic syndrome - a cluster of clinical manifestations including insulin resistance, high blood pressure, and blood fat abnormalities - is a concern because it increases the risk for cardiovascular disease and type 2 diabetes, especially in older individuals. The syndrome is common among people with HIV, and studies suggest an association with the virus itself or with drugs used to treat it, especially protease inhibitors. However, metabolic syndrome is common among the HIV negative general population as well, linked with a growing epidemic of obesity.

As described in the December 1, 2006 Journal of Acquired Immune Deficiency Syndromes, researchers conducted a study to determine the incidence and risk factors for metabolic syndrome among HIV positive adults in the Nutrition for Healthy Living (NFHL) study (2000-2003). The prevalence of metabolic syndrome in this cohort was compared with that observed in the National Health and Nutrition Examination Survey (NHANES) (1999-2002), a large study of the health of the general U.S. population.

Metabolic syndrome was defined as having 3 or more of the following manifestations:

• High serum glucose;
• Hypertriglyceridemia (high triglycerides);
• Low HDL ("good") cholesterol;
• Hypertension (high blood pressure);
• Abdominal obesity.

The researchers compared the baseline prevalence of metabolic syndrome among 477 participants in the NFHL study and 1876 participants in NHANES, adjusted for age, race, gender, poverty, exercise, and diet.

Results

• Almost one quarter of NFHL subjects had metabolic syndrome.
• Most individuals with metabolic syndrome (77%) had low HDL and hypertriglyceridemia plus 1 additional abnormality.
• The prevalence of metabolic syndrome was significantly lower among both HAART-treated and untreated HIV positive individuals compared with NHANES participants when unadjusted for body mass index (BMI).
• After adjustment for BMI, the difference was no longer significant, but the trend remained.
• The incidence of metabolic syndrome in the NFHL study was associated with the following factors:

- increasing HIV viral load;
- higher BMI;
- higher trunk-to-limb fat ratio;
- use of lopinavir/ritonavir (Kaletra)
- use of ddI (didanosine; Videx);
- less than college education.

Conclusion

"Metabolic syndrome is mostly diagnosed through low HDL and high triglycerides in [people with] HIV," the authors concluded. "The risk of developing the syndrome is related to HIV, specific medications, and body fat."

Tufts University School of Medicine, Boston, MA; Tufts-New England Medical Center, Boston, MA; Harvard School of Public Health, Boston, MA,.

1/09/07

Reference
D L Jacobson, A M Tang, D Spiegelman, and others. Incidence of Metabolic Syndrome in a Cohort of HIV-Infected Adults and Prevalence Relative to the US Population (National Health and Nutrition Examination Survey). Journal of Acquired Immune Deficiency Syndromes 43(4): 458-466. December 1, 2006.