Metabolic syndrome is a cluster of risk factors for cardiovascular disease and type 2 diabetes. Definitions exist to identify those "at risk." Treatment of HIV infection with highly active antiretroviral therapy can induce severe metabolic complications including lipodystrophy, dyslipidemia, and insulin resistance. The purpose of this study was to report the prevalence of metabolic syndrome in HIV-infected patients and compare insulin resistance and total body, limb, and visceral fat and adipokines in those with and without metabolic syndrome.
This was an international cross-sectional study of a well-characterized cohort of 788 HIV-infected adults recruited at 32 centers. Metabolic syndrome prevalence was examined using International Diabetes Federation (IDF) and U.S. National Cholesterol Education Program Adult Treatment Panel III (ATPIII) criteria, relative to body composition (whole-body dual-energy X-ray absorptiometry and abdominal computed tomography), lipids, glycemic parameters, insulin resistance, leptin, adiponectin, and C-reactive protein (CRP).
The prevalence of metabolic syndrome was 14% (n = 114; 83 men) by IDF criteria and 18% (n = 139; 118 men) by ATPIII criteria; the concordance was significant but only moderate (kappa = 0.46, P < 0.0001). Many patients (49%) had at least two features of metabolic syndrome but were not classified as having metabolic syndrome as their waist circumferences or waist-to-hip ratios were in the non-metabolic syndrome range. Metabolic syndrome was more common in those currently receiving protease inhibitors (P = 0.04). Type 2 diabetes prevalence was five- to ninefold higher in those with metabolic syndrome. With IDF criteria, subjects with metabolic syndrome showed disturbances in inflammation and adipokines: they had higher CRP (5.5 +/- 7.0 vs. 3.9 +/- 6.0 mg/l, P < 0.003) and leptin (9 +/- 9 vs. 4 +/- 6 ng/ml, P < 0.0001) and lower adiponectin (12 +/- 8 vs. 15 +/- 10 microg/ml, P < 0.0001) levels. By ATPIII criteria, those with metabolic syndrome had higher leptin (6 +/- 8 ng/ml, P = 0.006) and lower adiponectin (15 +/- 10 vs. 18 +/- 8 microg/ml, P < 0.0001) levels.
Metabolic syndrome prevalence in HIV-positive adults was lower than that reported for the general population. Metabolic syndrome was associated with a substantially increased prevalence of type 2 diabetes in this specific cohort. Many subjects without metabolic syndrome had at least two metabolic syndrome components (particularly elevated lipid levels) but did not meet waist circumference or waist-to-hip ratio cutoff metabolic syndrome criteria in this group with high rates of body fat partitioning disturbances.