MSM NeurocogNeurocognitive Function in a Central London Cohort of HIV Infected and Uninfected Men Who Have Sex With Men

The aim of this project is to examine neurocognitive functioning in HIV infected men who have sex with men (MSMs). We have limited our study to this group in order to better study other shared risk factors (hepatitis coinfection, recreational drug use). Given ongoing work in an older cohort our aim is to study neurocognitive impairment in younger subjects (18-49 years). There are two parts to this study. The first is a cross sectional pilot (MSM Neurocog-1) looking at neurocognitive function in HIV infected and HIV uninfected MSMs. The second plan is for a prospective 48 week cohort study 24-48 week study (MSM Neurocog-2) following neurocognitive function in HIV infected subjects and a group of HIV uninfected controls over time. The shift in HIV care to that of a chronic, manageable condition has transferred focus to long-term morbidities and drug toxicities. One such area in which there is renewed interest is the prevalence and relevance of neurocognitive impairment, as well as the significance of compartmentalised virus in the CSF as compared to blood. Controlled, comparative data are lacking - many of the cross-sectional studies to date have not controlled for important confounders such as recreational and injecting drug use, current or prior co-infections or co-morbidities. Where this has happened, researchers generally use general population controls that may differ markedly from HIV-infected individuals in terms of lifestyle and demographic factors. In addition the paucity of longitudinal data means it is unclear whether an individual with normal neurocognitive function pre-ART will develop impairment later or if subjects with evidence of impairment can expect improvement or normalisation over time; these issues are highly important for clinical management and patient counselling. There is no consensus on which surrogate markers, if any, are important in terms of diagnosing, monitoring and/or predicting neurocognitive impairment. Studies measuring correlation between neurocognitive performance and neuronal markers of inflammation have been conflicting.