Gait speed and neurocognition among older people with and without HIV.

Examine the associations of gait speed with global and domain-specific neurocognition in older people with HIV (PWH) versus people without HIV (PWoH). Participants included 285 PWH and 214 PWoH 50 years and older (Mage= 60.1, SD age=7.1) who completed a gait examination and a comprehensive neurocognitive assessment. Gait speed was significantly slower in PWH (M=3.3 s, SD=1.1) than PWoH (M = 3.0 s, SD = 0.9; p = .006). Slower gait speed was significantly associated with poorer global neurocognition (β= -0.17, p = .009) and deficits in multiple neurocognitive domains, including verbal fluency, executive functioning, processing speed, and motor skills, after adjusting for sociodemographic, HIV-related, and medical characteristics in PWH. A significant interaction between gait speed and HIV status emerged for verbal fluency, suggesting differential cognitive impacts (β=-0.45, p = .008). Our findings highlight nuanced relationships between gait speed and neurocognition, emphasizing the need for longitudinal research to establish causal mechanisms and potential clinical screening approaches.