Marked improvement in survival following AIDS dementia complex in the era of highly active antiretroviral therapy

Abstract

To determine the effect of introduction of highly active antiretroviral therapy (HAART) on survival following AIDS dementia complex (ADC). Australian AIDS notification data in the period 1993-2000 were examined. In order to examine the impact of HAART, two periods of AIDS diagnoses were chosen: pre-HAART (1993-1995) and HAART (1996-2000). Median survival was based on Kaplan-Meier estimates, with examination of factors influencing survival in a Cox proportional hazards model. In the period 1993-2000 in Australia, 5017 initial AIDS illnesses were diagnosed among 4351 AIDS patients. The proportion of AIDS cases with ADC increased from 5.2% in 1993-1995 to 6.8% in 1996-2000 (P = 0.029). Median survival following AIDS increased from 19.6 months for those diagnosed with AIDS in 1993-1995 to 39.6 months for those diagnosed in 1996-2000 (P < 0.0005). Median survival following ADC increased to a greater extent than that for all other AIDS illnesses, from 11.9 months in 1993-1995 to 48.2 in 1996-2000 (P < 0.0005). Most striking was the increase in survival among those with ADC and a CD4 cell count < 100 x 10(6) cells/l at diagnosis; 5.1 months in 1993-1995 to 38.5 months in 1996-2000 (P < 0.0005). Although there has been a proportional increase in ADC at AIDS diagnosis, survival following ADC has improved markedly in the era of HAART.