Compared to the general population, persons with HIV infection have a higher risk of premature death even before their immune system deteriorates to the point at which doctors have traditionally begun antiretroviral treatment (ART), a new study shows. The analysis is based on data for 40,830 patients ages 20 to 59 in 23 countries in the European Union and North America.
The pooled cohort observational study provides further evidence that ART should begin earlier, rather than delaying it until the immune system has deteriorated significantly. A CD4 count of 200 cells/microliter or lower increases the chance of infections and AIDS-related illnesses. Yet in the developing world, treatment has generally begun only when the count falls to 200. UNAIDS recently adopted a strategy of initiating ARVs when CD4 counts reach 350 or lower.
The study focused on ART-naive HIV patients with at least one CD4 count greater than 350. Adjusting for other mortality risks, untreated heterosexual patients were nearly three times as likely to die prematurely as uninfected peers. Injection drug users were more than nine times as likely to die, and those with unknown/other risk factors were 4.5 times as likely to die. For men who have sex with men, the risk was 30 percent greater.
Compared with CD4 counts of 350-499 cells per microliter, the death rate was lower in patients with counts of 500-699 cells per microliter (adjusted rate ratio 0.77, 95 percent confidence interval 0.61-0.95) and counts of 700 cells per microliter or greater (0.66, 0.52-0.85), the researchers reported.
"The increase in risk was substantial in injecting drug users and the heterosexual group, but was small in men who have sex with men," the authors said. "This finding suggests that much of the raised risk in the former two risk groups probably results from confounding by socioeconomic and lifestyle factors rather than being an effect of HIV infection itself. The magnitude of the raised risk in the [MSM] group is more likely to reflect the effect of HIV itself."
The full study, "Death Rates in HIV-Positive Antiretroviral-Naive Patients With CD4 Count Greater Than 350 Cells per µL in Europe and North America: A Pooled Cohort Observational Study," was published in the Lancet (2010;doi:10.1016/S0140-6736(10)60932-4).