Effects of highly active antiretroviral therapy on the survival of HIV-infected adult patients in urban slums of Kenya

Recent improvements in access to Anti-Retroviral Therapy (ART) have radically reduced hospitalizations and deaths associated with HIV infection in both developed countries and sub-Saharan Africa. Not much is known about survival of patients on ART in slums. The objective of this study was to identify factors associated with mortality among adult patients on ART in resource poor, urban, sub-Saharan African setting. A prospective open cohort study was conducted with adult patients on ART at a clinic in Kibera slums, Nairobi, Kenya. The patients’ enrollment to care was between March 2005 and November 2011. Descriptive statistics were computed and Kaplan-Meier (KM) methods used to estimate survival time while Cox's proportional hazards (CPH) model fitted to determine mortality predictors. A total of 2,011 adult patients were studied, 69% being female. Female gender (p = 0.0016), zidovudine-based regimen patients (p < 0.0001), CD4 count >351 patients (p < 0.0001), WHO stage I patients (p < 0.0001) and “Working” functional status patients recorded better survival probability on ART. In CPH analysis, the hazard of dying was higher in patients on Stavudine-based regimen(hazard ratio (HR) =1.8; 95% CI, 1.5-2.2; p < 0.0001),CD4 count <50 cells/µl (HR = 1.6; 95% CI, 1.5-1.7;p < 0.0001), WHO Stage IV at ART initiation (HR = 1.3; 95% CI, 1.1-1.6; p = 0.016) and bedridden patients (HR = 2.7; 95% CI, 1.7-4.4;p < 0.0001). There was increased mortality among the males, those with advanced Immunosuppression, late WHO stage and bedridden patients. The findings further justify the need to switch patients on Stavudine-based regimen as per the WHO recommendations.