Focus on Hepatitis: HIV/HCV Coinfection and CVD Risk
Coinfection with hepatitis C virus (HCV) increases the risk of cardiovascular disease (CVD) in HIV-positive patients, according to a study published in the January 11, 2007, edition of the journal AIDS. The investigators found that the relationship between HCV infection and increased CVD risk, such as hardening of the arteries, stroke and heart attack, persisted even when they adjusted for factors including age, gender, race, blood pressure, drug use, and smoking. Numerous studies have found a connection between chronic infections and an increased risk for CVD. However, there are conflicting data regarding any such association and infection with HCV.
Heart disease is an increasing concern for HIV-positive patients, many of whom are benefiting from the prolonged prognosis that antiretroviral therapy makes possible. But this means that some individuals are now living long enough to develop cardiovascular illnesses, and an association has been found between the use of antiretroviral therapy and a long-term risk of increased metabolic disorders and heart disease. In addition, many HIV-positive patients (as many as 30% in some cohorts) are HCV-coinfected. The investigators from the HIV-Live (HIV-Longitudinal Interrelationships of Viruses and Ethanol) study therefore wished to see if there was any association between HCV coinfection in a prospective cohort of HIV-positive patients with a history of substance abuse.
A total of 395 individuals were included in the investigators' analysis. Exactly half of the study population was HCV-coinfected. Patients were asked to complete a questionnaire about their health and specify if their physicians had ever been told them that they had atherosclerosis; had a stroke; or, had a heart attack. Data were also gathered on the patients' age, gender, race, current CD4 count, weight, adherence to antiretroviral therapy, blood pressure, alcohol consumption, drug use, and housing status. Patients were also asked to state if they had diabetes, renal disease, or lipodystrophy.
HIV/HCV-coinfected individuals were significantly older than HIV-monoinfected patients (44 versus 41 years), and had a higher prevalence of health complaints, including diabetes (10% versus 4%), cirrhosis (10% versus 3%), heart attack (7% versus 1%), and CVD (11% versus 3%). All these differences were statistically significant (P < 0.05).
After adjusting their results for age, the association between HCV coinfection and both CVD and heart attack persisted (OR: 4.65 and 12.86, respectively). The investigators then looked to see if any possible confounding factors including gender, race, alcohol consumption, current CD4 count, antiretroviral therapy, lipodystrophy, or the use of illicit substances such as crack, cocaine, or injected drugs affected these results. They write, "When individual cofounders were added separately to the age-adjusted models, the relationship between [HCV] and [CVD] remained unchanged."
The investigators acknowledge that their study had limitations, in particular that patients were asked to self-report their health histories. Nevertheless, they conclude that, "among HIV-infected individuals, coinfection with [HCV] may be independently associated with an increased risk of [CVD]."
Editor's Note: Reprinted with permission from www.aidsmap.com (first e-published January 4, 2007).
This article was provided by International Association of Physicians in AIDS Care. It is a part of the publication IAPAC Monthly.