Half of the deaths in people with HIV now are from causes other than AIDS, according to a study presented at the 16th Conference on Retroviruses and Opportunistic Infections (CROI) in Montreal. Non-AIDS-related cancers and cardiovascular disease are a growing cause of death particularly in older people with HIV.

Testifying to the success of antiretroviral (ARV) therapy, death rates have plummeted since the early 1990s. Yet as the rates of most AIDS-related conditions have declined well below 25 percent of what they once were, other diseases are emerging as substantial risk factors.

To determine the most important causes of mortality among people with HIV, John Gill, MSc, from the University of Calgary in Canada and his colleagues examined the circumstances surrounding the deaths of 1,597 people with HIV enrolled in one of 13 cohort studies in Europe and North America between 1996 and 2006. Those who died were compared with more than 36,000 other people with HIV in the cohorts who did not die during the study period.

Deaths were AIDS-related in 63 percent of those who died within their first year of taking combination ARV therapy. After the first year of treatment, the rate of deaths that were AIDS-related dropped to 43 percent. Twelve percent of the deaths were from non-AIDS-related cancers; 9 percent were from heart attacks, strokes or other forms of heart disease; 8 percent were from non-AIDS-related infections; and 7 percent were from liver disease.

When Gill’s team looked at the influence of CD4 counts on death, it found not-surprisingly that people with fewer than 100 CD4 cells before starting HIV treatment were four times more likely to die from AIDS-related causes than people with CD4 counts above 350. They also found, however, that people with pre-treatment CD4 counts below 100 were 61 percent more likely to die from heart problems, 96 percent more likely to die from respiratory diseases such as emphysema and nearly 11 times more likely to die from kidney failure. There was also a particularly strong association between older age and the likelihood of dying from a non-AIDS-related cancer or heart disease among all individuals.

People with a history of injection drug use were six times more likely to die from liver disease, five times more likely to die from lung diseases, nearly four times as likely to die from heart disease and nearly three times as likely to die from cancer as people with no history of injection drug use. They were also nearly four times as likely to die as a victim of violence.

Gill’s team recommends that further research and efforts must be explored to understand and treat these non-AIDS-related causes of death.