Individuals with AIDS dementia complex are living considerably longer because of HAART, according to an Australian study published in the July 4th edition of the journal AIDS.
Although the impact of HAART on slowing HIV disease progression has been well documented, the impact of HAART on survival after an AIDS defining illness has been diagnosed is less well studied. In particular, AIDS dementia complex (ADC) in the HAART era has been the subject of few studies.
Accordingly, Australian investigators looked at the impact of HAART on survival following a diagnosis of ADC and the prevalence of ADC at a population level in both the pre-HAART and HAART eras. The study included all reported initial AIDS-defining illnesses reported to the Australian National AIDS Register between 1993 and 2000.
The period from 1993 to 1995 was considered pre-HAART and 1995 to 2000 as the HAART era. Between 1993 and 2000 a total of 4351 initial AIDS-defining illnesses were reported, peaking in 1994 with 949, and declining to 217 in 2000. A total of 254 cases of ADC were diagnosed between 1993 and 2000, again peaking in 1994 with 56 cases.
After the introduction of HAART the incidence of ADC fell markedly. However, the prevalence of ADC amongst patients with AIDS increased from 5.2% in the pre-HAART era to 6.8% post-HAART. This was directly attributable to a increased survival in patients with ADC after the introduction of HAART. Prior to HAART, average survival time after diagnosis of ADC as the first AIDS-defining event was 11.9 months; this increased to 48.2 months after 1996 (p<.0005>
An even more dramatic improvement was seen in the prognosis of patients who had severe immune suppression, a CD4 cell count below 100 cells/mm3, and ADC as an initial AIDS defining illness. Amongst these patients HAART led to an increase in average survival from 5.1 months in the period up to 1995 to 38.5 months after 1996.
”There has been a marked improvement in survival following diagnosis with ADC in Australia over the period 1993 to 2000. The most dramatic aspect of this change has been a greater than sevenfold improvement in survival for people diagnosed with ADC in association with very advanced immunodeficiency” , note the investigators. They add that this improvement “is a direct result of improved antiretroviral therapy for people with HIV infection.”
However, despite declining incidence of ADC, the prevalence of ADC has increased, and the investigators conclude that “an increasing number of people living with ADC indicates a continuing need for ADC treatment snd care services”.
Further information on this website
HIV-associated dementia - overview
Dementia - factsheet
Dore GJ et al. Marked improvement in survival following AIDS dementia complex in the era of highly active antiretroviral therapy. AIDS 17: 1539 – 1545, 2003.