The global burden of cognitive impairment in people with HIV.

OBJECTIVE: While life expectancies of people with HIV (PWH) have increased through the successes of antiretroviral treatment, cognitive impairment remains a pressing concern. Prevalence estimates vary worldwide as different definitions for cognitive impairment are used and resource availability differs across geographical settings. We aim to explore this heterogeneity and estimate the global cognitive impairment burden in PWH. DESIGN: Systematic literature review and meta-analysis. METHODS: We searched PubMed, Embase, SCOPUS, and Web of Science for studies reporting on cognitive impairment prevalence in PWH. Nine factors were investigated for their potential association with the prevalence using a univariate meta-analysis and a meta-regression: assessment method, geographical region, country income, exclusion criteria, study quality, age, sex, publication year, and sample size. RESULTS: The literature search identified 8539 records, of which 225 were included. The adjusted prevalence was significantly lower in males than females. Across 44 countries, 12 assessment methods were used; the HIV-associated neurocognitive disorder/Frascati criteria, known for high false-positive rates, was employed in 44.4% of studies. The pooled cognitive impairment prevalence estimate in PWH, including asymptomatic cases, was 39.6% (95% confidence interval: 37.2-42.1%; range: 7-87%). The meta-regression explained 13.3% of between-study variation, with substantial residual heterogeneity ( I2  = 97.7%). CONCLUSION: Lack of data from more than 70% of the world's countries, cohorts being unselected for symptoms in most research studies, and limitations of the HIV-associated neurocognitive disorder/Frascati criteria restrict the ability to accurately determine the global burden of cognitive impairment in PWH. More studies in low-resource settings and a standardized approach to assessing cognitive impairment, bridging research and clinical realms, are needed.