Sleep and cognition in South African patients with non-functioning pituitary adenomas.

Strong lines of evidence in the neuroscience literature indicate that (a) healthy sleep facilitates cognitive processing, and (b) sleep disruption is associated with cognitive dysfunction. Despite the fact that patients with pituitary disease often display both disrupted sleep and cognitive dysfunction, few previous studies investigate whether these clinical characteristics in these patients might be related. Hence, we explored whether sleep disruption in patients with pituitary disease mediates their cognitive dysfunction. We recruited 18 patients with non-functioning pituitary adenomas (NFPA) and 19 sociodemographically matched healthy controls. They completed the Global Sleep Assessment Questionnaire (thus providing self-report data regarding sleep disruption) and were administered the Brief Test of Adult Cognition by Telephone, which assesses cognitive functioning in the domains of processing speed, working memory, episodic memory, inhibition, and reasoning. We found no significant differences in cognition between patients and controls. Furthermore, spectra of sleep disturbance did not differ significantly between patients and controls. Our data suggest that NFPA patients' cognition and sleep quality is relatively intact, and that sleep disruption does not mediate cognitive dysfunction. Larger studies should characterize sleep and cognition in patients with NFPA (and other pituitary diseases) to confirm whether disruption of the former mediates impairment in the latter.

Cognitive impairment in people living with HIV: consensus recommendations for a new approach.

Current approaches to classifying cognitive impairment in people living with HIV can overestimate disease burden and lead to ambiguity around disease mechanisms. The 2007 criteria for HIV-associated neurocognitive disorders (HAND), sometimes called the Frascati criteria, can falsely classify over 20% of cognitively healthy individuals as having cognitive impairment. Minimum criteria for HAND are met on the basis of performance on cognitive tests alone, which might not be appropriate for populations with diverse educational and socioeconomic backgrounds. Imprecise phenotyping of cognitive impairment can limit mechanistic research, biomarker discovery and treatment trials. Importantly, overestimation of cognitive impairment carries the risk of creating fear among people living with HIV and worsening stigma and discrimination towards these individuals. To address this issue, we established the International HIV-Cognition Working Group, which is globally representative and involves the community of people living with HIV. We reached consensus on six recommendations towards a new approach for diagnosis and classification of cognitive impairment in people living with HIV, intended to focus discussion and debate going forward. We propose the conceptual separation of HIV-associated brain injury - including active or pretreatment legacy damage - from other causes of brain injury occurring in people living with HIV. We suggest moving away from a quantitative neuropsychological approach towards an emphasis on clinical context. Our recommendations are intended to better represent the changing profile of cognitive impairment in people living with HIV in diverse global settings and to provide a clearer framework of classification for clinical management and research studies.

Youth perinatal HIV-associated neurocognitive disorders: association with functional impairment.

HIV-associated functional impairment may cause cognitive impairment secondary to the viral infection, hence, associations between cognitive impairment and functional impairment in youth living with HIV are important to assess. We sought to determine whether cognitive impairment is associated with functional impairment and if it carries higher risk for also having functional impairment. We collected parent-rated information regarding youth functional impairment on four different measures and administered a cognitive battery to youth to determine cognitive impairment, 203 HIV-infected youth and 44 HIV-uninfected controls. Degree of cognitive impairment correlated strongly with decreased function: CBCL, r = -.17, p = .01; VABS2, r = -.28, p < .001; repeated-grades, r = .26, p < .001. Presence of cognitive impairment was associated with increased risk of functional impairment: 3.47 (CIS); 1.71 (CBCL); 2.17 (VABS2); 2.97 (repeated-grades). Repeated-grades strongly associated with cognitive impairment and functional impairment. We found strong associations between HIV-infected youth functional impairment on CBCL, VABS2 and repeated-grades with degree of cognitive impairment; and that when cognitive impairment was present youth had higher risk of experiencing functional impairment as well. Asking whether youth have repeated a grade at school could be a helpful screening question for assessing potential functional impairment and provide clinicians with an indication as to whether a further in-depth assessment is required.

Screening for HIV-associated neurocognitive disorders in perinatally infected adolescents: youth-International HIV Dementia Scale validation.

CONTEXT: Perinatal HIV infection has adverse cognitive consequences into adolescence. However, there are no screening tools that assess risk for HIV-associated neurocognitive disorders in adolescent populations. Such screening tools are needed urgently for clinical care in resource-poor settings with a high prevalence of HIV. OBJECTIVE: To investigate the performance of the International HIV Dementia Scale (IHDS) as a screening tool for HIV-associated neurocognitive disorders in perinatally adolescents. DESIGN: The current study is a quantitative, quasiexperimental design. METHODS: Perinatally HIV-infected adolescents aged 9-12 years were recruited from community health clinics into the Cape Town Adolescent Antiretroviral Cohort; matched HIV-negative controls from the same communities were enrolled. Each participant completed the IHDS and a comprehensive neuropsychological battery. The adult version of the IHDS was performed, except for two minor modifications. We evaluated the diagnostic validity of this modified instrument, the youth-IHDS (y-IHDS), using a four-step process that included sensitivity and specificity calculations, and generating receiver operating characteristic curves. Validity was measured against the youth HIV-associated diagnostic criteria. RESULTS: At a cut-off score of 10 or less, the y-IHDS demonstrated good sensitivity (94%) but poor specificity (24%) for detecting all forms of neurocognitive disorders, with an acceptable area under the curve value of 0.695. CONCLUSION: The y-IHDS requires minimal resources and is based on a screening tool for adult HIV-associated cognitive disorders that is already widely used globally. Hence, this brief, cost-efficient, and valid screening tool may be a useful addition for clinicians working in resource-poor contexts in which adolescent HIV is highly prevalent.

A Smartphone App to Screen for HIV-Related Neurocognitive Impairment.

BACKGROUND: Neurocognitive Impairment (NCI) is one of the most common complications of HIV-infection, and has serious medical and functional consequences. However, screening for it is not routine and NCI often goes undiagnosed. Screening for NCI in HIV disease faces numerous challenges, such as limited screening tests, the need for specialized equipment and apparatuses, and highly trained personnel to administer, score and interpret screening tests. To address these challenges, we developed a novel smartphone-based screening tool, NeuroScreen, to detect HIV-related NCI that includes an easy-to-use graphical user interface with ten highly automated neuropsychological tests. AIMS: To examine NeuroScreen's: 1) acceptability among patients and different potential users; 2) test construct and criterion validity; and 3) sensitivity and specificity to detect NCI. METHODS: Fifty HIV+ individuals were administered a gold-standard neuropsychological test battery, designed to detect HIV-related NCI, and NeuroScreen. HIV+ test participants and eight potential provider-users of NeuroScreen were asked about its acceptability. RESULTS: There was a high level of acceptability of NeuroScreen by patients and potential provider-users. Moderate to high correlations between individual NeuroScreen tests and paper-and-pencil tests assessing the same cognitive domains were observed. NeuroScreen also demonstrated high sensitivity to detect NCI. CONCLUSION: NeuroScreen, a highly automated, easy-to-use smartphone-based screening test to detect NCI among HIV patients and usable by a range of healthcare personnel could help make routine screening for HIV-related NCI feasible. While NeuroScreen demonstrated robust psychometric properties and acceptability, further testing with larger and less neurocognitively impaired samples is warranted.

Validity of the International HIV Dementia Scale in South Africa.

HIV-associated neurocognitive disorders (HAND) remain prevalent, especially in regions like South Africa where HIV prevalence is high but access to antiretroviral treatment (ART) is limited. The incidence of HIV dementia (HAD) has been halved with the use of ART, but the prevalence remains high. Appropriate brief screening tools to screen for HAD are needed in order to facilitate treatment initiation. The validity of the International HIV Dementia Scale has not been established in a region where infection with HIV clade C is predominant. The International HIV Dementia Scale (IHDS) was administered together with a detailed neuropsychological test battery to 96 HIV-positive individuals who had not received ART and who were attending primary care HIV clinics. The validity of the IHDS was established using a receiver operating characteristic (ROC) analysis. HIV-positive individuals displayed greater impairment when compared to HIV-negative controls on the IHDS and a range of neuropsychological tests. Neuropsychological tests discriminated well across HAND categories for HIV-positive individuals. In ROC analysis, the IHDS showed an area under the curve of 0.64, with a sensitivity of 45% and specificity of 79% at a cutoff score of 10. Individuals with HAD, who screened negative on the IHDS, performed poorly on some tests of executive function. These data suggest that the IHDS may have limitations as a tool to screen for HAD in South Africans infected with HIV. Variable performance in neuropsychological testing may account for false negative screens. The inclusion of brief tests of executive function in a screening battery should be considered.

Neuropsychological performance of South African treatment-naïve adolescents with alcohol dependence.

BACKGROUND: Alcohol dependence (AD) in developmentally vulnerable adolescents is ubiquitous and confers a risk for long-term neurocognitive sequelae, yet comorbid substance use disorders and psychopathology can complicate interpretations. Here, we compare cognitive functioning in adolescents with and without AD, who are free from comorbid disorders. METHODS: English- and Afrikaans-speaking adolescents (13-15 years) of mixed ancestry and low socio-economic status were recruited from the Cape Town region of South Africa. Adolescents with psychiatric, developmental, or other substance use disorders (SUDs) were excluded. AD (n=26) and control (n=26) groups were matched on age, gender, language, and level of education. Neuropsychological testing in participants' home language followed detailed medical/psychiatric evaluation. RESULTS: Although our sample included participants who smoked tobacco, lifetime dosage of other drugs was negligible. When tobacco and other drug use as well as demographic variables were controlled, adolescents with AD performed more poorly on measures of Verbal Story Memory, Self-Monitoring, and Psychomotor Speed and Coordination. CONCLUSIONS: These preliminary results, although relatively subtle, suggest that adolescents with AD may be at increased risk for failure to reach optimal levels of neuromaturation, and may be susceptible to cognitive problems associated with protracted alcohol consumption.