HIV-Associated Neurocognitive Disorders (HAND): The First Longitudinal Follow Up of a cART-Treated Cohort of Older People in Sub-Saharan Africa

Abstract

Background: HIV-associated neurocognitive disorders (HAND) are a highly prevalent chronic complication in older people living with HIV (PLWH) in high-income countries (HICs). Although Sub-Saharan Africa (SSA) has a newly emergent population of older cART treated PLWH, HAND have not been studied longitudinally. We assessed longitudinal prevalence of HAND and have identified possible modifiable risk factors in a population of PLWH aged ≥50, over three years of follow-up. Methods: Detailed neuropsychological and clinical assessment was completed annually 2016-2019 in a baseline systematic sample of cART treated PLWH in Kilimanjaro, Tanzania. A consensus panel defined HAND using American Academy of Neurology criteria for asymptomatic neurocognitive impairment (ANI), mild neurocognitive disorder (MND) and HIV-associated dementia (HAD). HIV-disease severity and other factors associated with HAND progression, improvement and stability were evaluated in individuals fully assessed at baseline and in 2019. Findings: At baseline 47% of the cohort (n=253, 72·3% female) met HAND criteria despite good HIV-disease control [Y1 59.5% (n=185), Y2 61·7% (n=162), Y3 57·9% (n=121)]. Of participants fully assessed at baseline and year 3 (n=121) HAND remained stable in 54% (n=57), improved in 15% (n=16), and declined in 31% (n=33). Older age and lower education level significantly predicted HAND progression, whereas HIV-specific factors did not. Male gender and shorter cART-treatment predicted improvement. Interpretation: In this first longitudinal study characterising clinical course of HAND in older cART treated PLWH in SSA, HAND was highly prevalent with variable progression and reversibility. Progression may be more related to cognitive reserve than HIV-disease in cART-treated PLWH. Funding Information: This study was part-funded by the Academy of Medical Sciences, Grand Challenges Canada and the Newcastle University Master’s in Research Programme. Declaration of Interests: None. Ethics Approval Statement: Ethical approval was granted by Kilimanjaro Christian Medical College Research Ethics and Review Committee (N·896) and the Tanzanian National Institute for Medical Research (NIMR/HQ/R·8a/Vol·IX/2136). Participants were provided with written and verbal study information as appropriate by trained nurses. Where participants lacked capacity to consent due to cognitive impairment, assent was sought from a close relative. Consent was reviewed annually, and additional informed consent was requested to obtain an informant history for corroboration of cognitive and functional decline.