Combination antiretroviral therapy improves psychomotor speed performance in HIV-seropositive homosexual men

Background: Combination antiretroviral therapy including protease inhibitors (combo +PI) is effective in suppressing systemic viral load in HIV infection, but its impact on PIN-associated cognitive impairment is unclear. Objective: To determine whether psychomotor speed, a sensitive measure of impairment in PIN dementia, improves with combo+PI compared with other antiretroviral treatments. Methods: A total of 411 HIV-seropositive (HIV+) homosexual men (with longitudinal neuropsychological testing) in the Multicenter AIDS Cohort Study and, in a separate analysis, 282 HIV+ homosexual men with psychomotor slowing at baseline were classified by treatment into four groups: antiretroviral naive (no antiretroviral medication treatment), monotherapy, combination antiretroviral therapy without protease inhibitors (combo-noPI), and combo+PI. We compared longitudinal performance on three tests of psychomotor speed: the Grooved Pegboard (GP) (nondominant and dominant hands), Trail Making Test B, and the Symbol Digit Modalities Test (SDMT). Results: Relative to antiretroviral-naive and monotherapy participants, on the GP nondominant hand test, combo+PI participants with abnormal baseline neuropsychological testing showed improved performance (difference = +0.63 standard deviation [SD],p = 0.02). For the SDMT, both combo+PI participants (difference = +0.26 SD, p = 0.03) and combo-noPI participants (difference = +0.29 SD, p = 0.01) with abnormal baseline neuropsychological testing improved compared with antiretroviral-naive and monotherapy groups. Conclusion: Combo+PI and combo-noPI are associated with improved psychomotor speed performance in HIV+ homosexual men with abnormal neuropsychological testing.