Illness and death in HIV-positive patients taking protease inhibitor-based antiretroviral therapy are likely to be causes unrelated to either HIV or the side-effects of HIV therapy, according to a prospective French cohort study presented to the 45th Interscience Conference on Antimicrobial Agents and Chemotherapy in Washington DC last month.
A total of 1281 patients who started protease inhibitor-based antiretroviral therapy between 1997 and 1999 were enrolled on the prospective cohort. Doctors were asked to declare deaths, HIV-related events, physical and laboratory side-effects of HIV therapy and other events. These events were then assessed by a panel of experts to determine if they were related to HIV, antiretroviral drugs or other causes. The five year probability of events in each of these categories was then calculated.
At five years, the probability of death was 10%, and the probability of an AIDS-defining event was 16%. There was a 30% probability of side-effects related to antiretroviral therapy. However, the investigators found that there was a 35% probability of severe illness or death due to a non-HIV, or antiretroviral therapy-related event.
The most frequent causes of these events due to causes other than HIV or its treatment were bacterial infections (15%), cardiovascular disease (5%), cancers (3%), liver disease (3%) and mental health problems (3%).
The only group of patients who were more likely to become ill or die because of HIV were patients who started protease inhibitor-based therapy with a CD4 cell count below 50 cells/mm3 (AIDS/AIDS-related death, 38%; antiretroviral side-effects, 35%; other serious event, 33%).
The investigators also observed a different pattern of risk for patients coinfected with hepatitis B or C virus. These patients were more likely to experience severe side-effects caused by antiretroviral therapy (AIDS/AIDS-related death, 18%; side-effects, 43%; other serious event, 42%). Injecting drug users were equally likely to experience side-effects and illness due to causes other than HIV (AIDS/AIDS death, 14%; side-effects, 39%; other causes, 39%).
“Severe events neither related to AIDS nor antiretroviral therapy have become the most frequent morbid events in HIV-infected patients treated with HAART”, conclude the investigators.
Le Moing V et al. Morbidity during five years following initiation of protease inhibitor therapy in HIV-infected patients. 45th Interscience Conference on Antimicrobial Agents and Chemotherapy, abstract H-515, New Orleans, 2005.