Risk of deaths, AIDS-defining and non-AIDS defining events among Ghanaians on long-term combination antiretroviral therapy

Abstract

Combination antiretroviral therapy (cART) has been widely available in Ghana since 2004. The aim of this cohort study was to assess the incidences of death, AIDS-defining events and non-AIDS defining events and associated risk factors amongst patients initiating cART in a large treatment centre. Clinical and laboratory data were extracted from clinic and hospital case notes for patients initiating cART between 2004 and 2010 and clinical events graded according to recognised definitions for AIDS, non-AIDS events (NADE) and death, with additional events not included in such definitions such as malaria also included. The cumulative incidence of events was calculated using Kaplan Meier analysis, and association of risk factors with events by Cox proportional hazards regression. Data were closed for analysis on 31st December, 2011 after a median follow-up of 30 months (range, 0-90 months). Amongst 4,039 patients starting cART at a median CD4 count of 133 cells/mm3, there were 324 (8%) confirmed deaths, with an event rate of 28.83 (95% CI 25.78-32.15) deaths per 1000-person follow-up years; the commonest established causes were pulmonary TB and gastroenteritis. There were 681 AIDS-defining events (60.60 [56.14-65.33] per 1000 person years) with pulmonary TB and chronic diarrhoea being the most frequent causes. Forty-one NADEs were recorded (3.64 [2.61-4.95] per 1000 person years), of which hepatic and cardiovascular events were most common. Other common events recorded outside these definitions included malaria (746 events) and respiratory tract infections (666 events). Overall 24% of patients were lost-to-follow-up. Alongside expected risk factors, stavudine use was associated with AIDS [adjusted HR of 1.08 (0.90-1.30)] and death (adjusted HR of 1.60 [1.21-2.11]). Whilst frequency of AIDS and deaths in this cohort were similar to those described in other sub-Saharan African cohorts, rates of NADEs were lower and far exceeded by events such as malaria and respiratory tract infections.

Figure 1. Six monthly incidence rates of Non-AIDS and AIDS events, deaths, loss to follow up and asymptomatic events among Ghanaian HIV-infected patients on long-term cART.

Non-AIDS events comprised all medical conditions which are non-AIDS defining by WHO criteria.