High Prevalence of Neurocognitive Impairment Found In a Large Cohort of HIV Patients

Although patients on HAART often achieve durable suppression of HIV viral load, a decreased incidence of HIV-related neurologic disease and increased survival, a significant number of these individuals also have developed HIV drug resistance and experienced multiple adverse events that can affect the central nervous system (CNS).

The extent to which HAART impacts the prevalence and incidence of HIV-related neurocognitive problems (positively or negatively) is not known. The current study had the ambitious objective of determining the prevalence of neurocognitive impairment in HAART-treated patients and of evaluating the relationship of virologic and immunologic factors to this impairment.

1498 individuals enrolled in ACTG A5001 took a battery of tests administered by study coordinators with specialized training. Neurocognitive impairment was defined as performance at least 1 standard deviation below norms for 2 tests, or 2 standard deviations on 1 test.

Results

·         Study participants were 54% white, 23% African American, 20% Hispanic; 85% male; median CD4 of 421, and HIV RNA 50; and age 40 years.

·         645 subjects were determined to have neurocognitive impairment.

·         Nadir CD4 count <200 (49%) was associated with prevalent neurocognitive impairment.

·         Concurrent HIV viral load and CD4 counts were not significantly associated with neurocognitive impairment.

·         Of 853 initially unimpaired subjects, 159 (18.6%) subsequently became neuro-psychologically impaired after 96 weeks of follow-up.

Based of these results, the study authors concluded, “This large cohort of individuals on HAART showed a high prevalence of neurocognitive impairment, a finding that suggests “neurocognitive impairment is still frequent even in the era of HAART. In addition, the incidence of neurocognitive impairment during follow-up was relatively frequent.”

“Low CD4 nadir (<200) was associated with an increased risk for of neurocognitive impairment. However, concurrent CD4 and viral load were not significantly associated with neurocognitive impairment, a finding that is distinctly different from pre-HAART cohorts.”

“Future studies should evaluate potential predictors or risk factors for incident impairment to help identify possible interventions to reduce the effect of neurocognitive impairment.”

02/17/06

Reference
K Robertson and others (the ACTG 5001 Protocol Team and the ACTG). Neurocognitive Impairment in HIV-infected Subjects on HAART: Prevalence and Associations. 13^th Conference on Retroviruses and Opportunistic Infections. Denver, CO. February 5-8, 2006. Abstract 362.