Incidence and prevalence of neurological disorders associated with HIV since the introduction of highly active antiretroviral therapy (HAART)

Objective-To determine the change of incidence and prevalence of neurologic al disorders caused by the human immuno-deficiency virus (HIV) and opportun istic infections in HIV positive patients under treatment since the introdu ction of highly active antiretroviral therapy (HAART). Methods The data of all HIV infected patients were retrospectively analysed , who were examined in the HIV outpatients clinic of the neurological depar tment of the University Clinic Essen between 1995 and 1998 (n=563, total nu mber of visits - =735). Data from identified patients were divided into two groups according to the time of examination from 1995 to 1996 (334 visits) and from 1997 to 1998 (401 visits). The incidence and prevalence of neurol ogical disorders were statistically compared between both time intervals. Results-Significantly more patients received HAART in 1997-8 (p<0.001) and mean CD4+ cell count was significantly higher in 1997-8 (p<0.001). The prev alence of HIV associated dementia and HIV associated polyneuropathy were si gnificantly lower in 1997-8 (both: p=0.02) and the incidence of toxoplasma encephalitis decreased from 5.7% in 1995-6 to 2.2% in 1997-8 (p=0.015). Bas ed on the small number of patients significant changes in HIV associated my opathy, progressive multifocal leukoencephalopathy, cryptoccocal meningitis , and cytomegalovirus-encephalitis could not be detected. Conclusion-The prevalence of the most frequent HIV associated neurological disorders and incidence of toxoplasma encephalitis decreased since the intr oduction of HAART. This may be due to the improvement of immunostatus by HA ART as demonstrated by the higher CD4+ cell. count in the later time interv al. Direct antiretroviral effects within the nervous system may be consider ed causative as well. The prevalence and incidence of HIV associated neurol ogical disorders and opportunistic CNS infections decreased after introduct ion of HAART.