Generalizability of demographically corrected Zambian neuropsychological norms to South African women

Neuropsychological Test Norms for the Assessment of HIV-Associated Neurocognitive Impairment Among South African Adults

Reliable and valid neurocognitive (NC) test batteries that assess multiple domains of cognitive functioning are vital tools in the early detection of HIV-associated NC impairment. The HIV Neurobehavioral Research Center's International Neurobehavioral Battery (HNRC Battery) is one such diagnostic tool and has shown cultural validity in several international neuroHIV studies. However, no published norms are currently available for the full HNRC Battery in South Africa. To accurately interpret NC test results, appropriate reference norms are required. In light of this challenge, data were collected from 500 healthy, HIV-uninfected participants to develop demographically corrected South African norms. When demographically corrected United States of America (U.S.) norms were applied to the performance scores of our neurologically intact, HIV-negative sample, an impairment rate of 62.2% was observed compared to a 15.0% impairment rate when the newly generated South African norms were applied. These results reiterate the findings of other low- and middle-income countries, highlighting the need for localized, country-specific norms when interpreting NC performance.

Screening for HIV-associated neurocognitive impairment: Development and validation of an abbreviated neuropsychological test battery for use in South African clinical settings

BACKGROUND

The HIV Neurobehavioral Research Center International Neurobehavioral Battery is a culturally valid battery sensitive to the neurocognitive (NC) effects of HIV-infection. However, its lengthy administration time makes the battery impractical in resource-limited settings, like South Africa, which are often faced with an overwhelming disease burden, a lack of neurological and neuropsychological (NP) expertise, and staff shortages. The present study therefore sought to develop an abbreviated version of the HNRC Battery and validate this battery in a sample of people with HIV (PWH) in South Africa.

OBJECTIVE

The present study therefore sought to develop an abbreviated version of the HNRC battery and validate this battery in a sample of people with HIV (PWH) in South Africa.

METHOD

Six measures were selected based on the NC test performances of 103 HIV-positive and 135 HIV-negative South African adults. For the validation, a subgroup of 103 PWH completed the full version of the battery, while the other subgroup of 52 PWH completed only the abbreviated version. Deficit scores of each participant were calculated. These scores were used as the gold standard against which the abbreviated battery was compared.

RESULTS

There was a reduction of 81% in administration time when compared to the full version of the battery. The abbreviated battery demonstrated good sensitivity (75.0%) and excellent specificity (94.9%) when compared with the full version. The abbreviated battery showed good diagnostic accuracy in identifying NC impairment in an HIV-positive South African sample with a significant reduction in administration time, making it a more practical option in busy South African clinic settings.

CONCLUSION

The results of this study may facilitate the growth of neuroAIDS research and aid initial identification of HIV-related NC impairment in resource-constrained settings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Effects of unhealthy alcohol use on brain morphometry and neurocognitive function among people with HIV

Individual impacts of alcohol misuse and HIV on brain structure and function have been well demonstrated; however, the potential compounded effect of these conditions is seldom considered, despite the high prevalence of alcohol use in HIV infection. We aimed to determine the effects of unhealthy alcohol use on brain morphometry and cognitive function amongst people with HIV (PWH). In 27 (50.9%) HIV-positive users of alcohol and 26 (49.1%) HIV-positive abstainers from alcohol, results revealed significant differences for left and right amygdala (p < 0.01), left and right hippocampus (p = 0.05), left and right posterior cingulate (p < 0.01), left and right precuneus (p < 0.01), left insula (p < 0.01), left and right caudate (p < 0.01), right thalamus (p < 0.01), and corpus callosum (p < 0.05). Mean volume of these regions was significantly smaller in HIV-positive alcohol users compared to HIV-positive abstainers. Homogeneity of slopes ANCOVA revealed significant associations between anterior cingulate cortex, precuneus, amygdala, hippocampus, and insula volumes and cognitive function in the domains of learning and delayed recall, motor function, speed of information processing, executive function, attention/working memory, and language. Among PWH, unhealthy alcohol use is associated with negative effects on brain structure and cognitive function.

Patterning of individual variability in neurocognitive health among South African women exposed to childhood maltreatment

There are individual differences in health outcomes following exposure to childhood maltreatment, yet constant individual variance is often assumed in analyses. Among 286 Black, South African women, the association between childhood maltreatment and neurocognitive health, defined here as neurocognitive performance (NP), was first estimated assuming constant variance. Then, without assuming constant variance, we applied Goldstein's method (Encyclopedia of statistics in behavioral science, Wiley, 2005) to model "complex level-1 variation" in NP as a function of childhood maltreatment. Mean performance in some tests of information processing speed (Digit-symbol, Stroop Word, and Stroop Color) lowered with increasing severity of childhood maltreatment, without evidence of significant individual variation. Conversely, we found significant individual variation by severity of childhood maltreatment in tests of information processing speed (Trail Making Test) and executive function (Color Trails 2 and Stroop Color-Word), in the absence of mean differences. Exploratory results suggest that the presence of individual-level heterogeneity in neurocognitive performance among women exposed to childhood maltreatment warrants further exploration. The methods presented here may be used in a person-centered framework to better understand vulnerability to the toxic neurocognitive effects of childhood maltreatment at the individual level, ultimately informing personalized prevention and treatment.