Working HAND in HAND: Central nervous system complications in people with HIV

Update on Central Nervous System Effects of HIV in Adolescents and Young Adults

PURPOSE OF REVIEW

: Behaviorally acquired (non-perinatal) HIV infection during adolescence and young adulthood occurs in the midst of key brain developmental processes such as frontal lobe neuronal pruning and myelination of white matter, but we know little about the effects of new infection and therapy on the developing brain.

RECENT FINDINGS

Adolescents and young adults account for a disproportionately high fraction of new HIV infections each year. Limited data exist regarding neurocognitive performance in this age group, but suggest impairment is at least as prevalent as in older adults, despite lower viremia, higher CD4 + T cell counts, and shorter durations of infection in adolescents/young adults. Neuroimaging and neuropathologic studies specific to this population are underway. The full impact of HIV on brain growth and development in youth with behaviorally acquired HIV has yet to be determined; it must be investigated further to develop future targeted treatment and mitigation strategies.

Abnormal cognitive aging in people with HIV: Evidence from Data Integration between two countries' cohort studies

OBJECTIVES

Previous research has shown inconsistent results on whether cognitive aging is abnormal in people with HIV (PWH) because of low sample size, cross-sectional design, and nonstandard neuropsychological methods. To address these issues, we integrated data from two longitudinal studies: Australian HIV and Brain Ageing Research Program (N = 102) and CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study (N = 924) and determined the effect of abnormal aging on neurocognitive impairment (NCI) among PWH.

METHODS

Both studies used the same neuropsychological test battery. NCI was defined based on demographically corrected global deficit score (≥0.5 = impaired). Both studies also assessed comorbidities, neuropsychiatric conditions and functional status using similar tools. To determine the cross-sectional and longitudinal effects of age on the risk of NCI, a generalized linear mixed-effect model tested main and interaction effects of age group (young, <50 vs. old, ≥50) and time on NCI adjusting the effects of covariates.

RESULTS

Older PWH had 83% higher chance of NCI compared with younger PWH [odds ratio (OR) = 1.83 (1.15-2.90), P < 0.05]. Older participants also had a greater risk of increases in NCI over the follow-up [OR = 1.66 (1.05-2.64), P < 0.05] than younger participants. Nonwhite ethnicity (P < 0.05), having a contributing (P < 0.05) or confounding (P < 0.001) comorbidity, greater cognitive symptoms (P < 0.001), and abnormal creatinine level (P < 0.05), plasma viral load greater than 200 copies/ml (P < 0.05), being from the Australian cohort (P < 0.05) were also associated with a higher risk of NCI.

CONCLUSION

Data integration may serve as a strategy to increase sample size and study power to better assess abnormal cognitive aging effect in PWH, which was significant in the current study.