Atherosclerosis risk increased with HIV; treatment effects unclear.

An important study by cardiologists, endocrinologists, and HIV physicians found more atherosclerosis in persons with HIV, and much faster progression, than in the general population. (1) The measurement used in this study--increasing thickness of the carotid artery, determined non-invasively by ultrasound examination--is known to be a predictor of strokes and heart attacks in other populations. But this study could not tell how much of the increased risk is due to HIV itself, and how much is due to metabolic abnormalities caused by protease inhibitors or other HAART treatment in some patients. (2)

Age, LDL cholesterol, and smoking (cigarette pack-years) were strong predictors of atherosclerosis in the 148 persons with HIV who were studied; Latino race and high blood pressure were weaker predictors. Other risks like diabetes would not have shown up in this study because of the small number of volunteers affected. When matched controls were added to the analysis, HIV infection itself was a strong predictor of greater atherosclerosis, independent of other factors.

The authors gave some practical clinical suggestions at the end of the article: "Although randomized trials have not been done to demonstrate that treatment of risk factors reduces events in HIV-infected patients, it seems reasonable to extrapolate from other populations and to recommend aggressive control of risk factors. Smoking is particularly important because of its high prevalence. Hypertension should be treated. LDL cholesterol should be reduced to low levels, and hypertriglyceridemia should be controlled. If lipids are difficult to control, antiretroviral medication that may be contributing to lipid elevation should be reviewed and changed to medication with fewer lipid effects. Until further data are available, treating to the National Cholesterol Education Panel guidelines(3) for patients with established vascular disease or diabetes seems prudent."

The researchers are from San Francisco General Hospital, and the Department of Medicine, University of California, San Francisco. The volunteers were mostly recruited from the University of California, San Francisco Study of the Consequences of the Protease Inhibitor Era (SCOPE) study.

References

(1) PY Hsue, JC Lo, A Franklin, AF Bolger, JN Martin, SG Deeks, and DD Waters. Progression of Atherosclerosis as Assessed by Carotid Intima-Media Thickness in Patients With HIV Infection. Circulation. 2004; volume 109, pages 1603-1608, April 6 (published online before print, March 15). The abstract is free at http://www.circulationaha.org--but the full article costs $15 online for nonsubscribers.

(2) Another recent study looked at triglyceride and cholesterol changes associated with different antiretrovirals, in a major analysis of data from over 7,000 HIV patients in 11 previously established cohorts. Some of its findings will be useful for particular patients, but overall it is hard to interpret this article. Reuters Health published a summary; you can find it on the AIDSMEDS site, at: http://www.aidsmeds.com/news/20040323clin001.html.

Here is the reference for the original article:

E Fontas, F van Leth, CA Sabin, and others. Lipid profiles in HIV-infected patients receiving combination antiretroviral therapy: Are different antiretroviral drugs associated with different lipid profiles? Journal of Infectious Diseases. March 15, 2004; volume 189, pages 1056-1074.

(3) Information on the National Cholesterol Education Program is available at: http://www.nhlbi.nih.gov/guidelines/cholesterol/index.htm