Global prevalence and burden of HIV-associated neurocognitive disorder

Objective To characterize the prevalence and burden of HIV-associated neurocognitive disorder (HAND) and assess associated factors in the global population with HIV.

Methods We searched PubMed and Embase for cross-sectional or cohort studies reporting the prevalence of HAND or its subtypes in HIV-infected adult populations from January 1, 1996, to May 15, 2020, without language restrictions. Two reviewers independently undertook the study selection, data extraction, and quality assessment. We estimated pooled prevalence of HAND by a random effects model and evaluated its overall burden worldwide.

Results Of 5,588 records identified, we included 123 studies involving 35,513 participants from 32 countries. The overall prevalence of HAND was 42.6% (95% confidence interval [CI] 39.7–45.5) and did not differ with respect to diagnostic criteria used. The prevalence of asymptomatic neurocognitive impairment, mild neurocognitive disorder, and HIV-associated dementia were 23.5% (20.3–26.8), 13.3% (10.6–16.3), and 5.0% (3.5–6.8) according to the Frascati criteria, respectively. The prevalence of HAND was significantly associated with the level of CD4 nadir, with a prevalence of HAND higher in low CD4 nadir groups (mean/median CD4 nadir <200 45.2% [40.5–49.9]) vs the high CD4 nadir group (mean/median CD4 nadir ≥200 37.1% [32.7–41.7]). Worldwide, we estimated that there were roughly 16,145,400 (95% CI 15,046,300–17,244,500) cases of HAND in HIV-infected adults, with 72% in sub-Saharan Africa (11,571,200 cases, 95% CI 9,600,000–13,568,000).

Conclusions Our findings suggest that people living with HIV have a high burden of HAND in the antiretroviral therapy (ART) era, especially in sub-Saharan Africa and Latin America. Earlier initiation of ART and sustained adherence to maintain a high-level CD4 cell count and prevent severe immunosuppression is likely to reduce the prevalence and severity of HAND.