VARIABLE PROGRESSION OF HIV-ASSOCIATED DEMENTIA

A consecutive series of 71 patients diagnosed with HIV-associated deme ntia (HAD) (1984-1994) were studied to characterize the clinical cours e of HAD, and to identify predictive markers of rapid neurologic progr ession. Neurologic progression rate was determined from the change in the Memorial Sloan Kettering (MSK) dementia severity score from diagno sis to death. Those with the most rapid progression in neurologic disa bility were compared with those with slow or no progression. Autopsy m aterial was immunostained for macrophage activation markers and gp41 i n 30 individuals. Median survival was 3.3 months and 6.1 months for ra pid-progression and no-progression patients, respectively. Rapid progr ession was associated with injection drug use but not with race, gende r, or age. CD4+ cell counts were lower at diagnosis among rapid-progre ssion than no-progression patients but no differences in AIDS-defining illnesses or patterns of antiretroviral therapy were found. At presen tation, rapid-progression patients had more prominent symptoms of ment al slowing than those with no progression; however, no other clinical features, CSF, or imaging features distinguished the groups. Less abun dant macrophage activation in both basal ganglia and midfrontal gyrus regions, as judged by HAM56 immunostaining, was noted in 9 no-progress ion patients, compared with 12 rapid-progression patients. Neurologic progression and survival with HAD is highly variable. A significant pr oportion of individuals with dementia have prolonged survival of more than 12 months and remain cognitively stable. A history of injection d rug use and presentation with prominent psychomotor slowing is associa ted with more rapid neurologic progression, and these patients tend to show more abundant macrophage activation within the CNS.