Persistent Detectable HIV Viral Load Is Linked to Metabolic Syndrome

		SUMMARY: HIV patients who do not maintain a viral load below the level of detection with antiretroviral therapy (ART) are more likely to develop metabolic syndrome -- and therefore may be at higher risk of cardiovascular disease -- according to an Italian study published in the December 2009 Journal of Acquired Immune Deficiency Syndromes.

By Liz Highleyman

A growing body of evidence indicates that ongoing HIV replication can cause problems throughout the body, well before the risk of opportunistic illness rises due to extensive immune system damage.

Many people with HIV have features of the metabolic syndrome, characterized by abnormal blood lipid levels (high triglycerides and low HDL or "good" cholesterol), insulin resistance, high blood pressure, and abdominal obesity -- all risk factors for cardiovascular disease. However, it is not clear whether this is related to chronic HIV infection itself, antiretroviral drugs, traditional risk factors, or some combination of factors.

Nicola Squillace from the University of Modena and Reggio Emilia and colleagues conducted a study to evaluate the association between HIV viral load and metabolic syndrome in a cohort of HIV positive patients.

The retrospective cross-sectional analysis included 1324 consecutive patients receiving stable ART regimens who were seen at a university clinic between January 2006 and January 2008. A majority (63%) were men and the mean age was about 45 years.

Results

	In a univariate (single variable) analysis, the following factors were significantly associated with metabolic syndrome:
	Older age: mean 47 years for patients with metabolic syndrome vs 44 years for those without (P < 0.0001); Male sex: 69% with metabolic syndrome vs 61% without (P = 0.009); Apolipoprotein B (ApoB): 111.51 vs 100.57 mg/dL, respectively (P < 0.0001); Insulin resistance: median HOMA-IR score 5.14 vs 2.95, respectively (P < 0.0001); Higher body mass index: 25.17 vs 22.80, respectively (P < 0.0001); Current protease inhibitor use: 62% vs 53%, respectively (P = 0.006); HIV viral load: 2.17 vs 2.02 log10, respectively (P = 0.0048).
	About one-third of people with HIV RNA > 400 copies/mL had metabolic syndrome, compared with about one-quarter of those with < 400 copies/mL.
	In a multivariate analysis adjusting for potential confounding, the following factors remained significant predictors of metabolic syndrome:
	HIV viral load: odds ratio (OR) 1.25 per log, or 25% higher risk (P = 0.003); Older age: OR 1.60 per 10-year increment (P < 0.0001); Insulin resistance: OR 2.77 -- nearly 3 times the risk -- if HOMA-IR > 3.8 (P < 0.0001).

Based on these findings, the investigators concluded, "Persistent viremia is a significant predictor for the development of metabolic syndrome."

They added, "Viral control through effective antiretroviral therapy is paramount not only for the control of HIV disease progression but also for the prevention of metabolic syndrome and associated cardiovascular disease."

Department of Medicine and Medical Specialties, Infectious Diseases Clinic, University of Modena and Reggio Emilia, Modena, Italy.

12/11/09

Reference
N Squillace, S Zona, C Stentarelli, and others. Detectable HIV Viral Load Is Associated With Metabolic Syndrome. Journal of Acquired Immune Deficiency Syndromes 52(4): 459-464 (Abstract). December 2009.