HIV-subtype A is associated with poorer neuropsychological performance compared with subtype D in antiretroviral therapy-naive Ugandan children

A pilot investigation of the association between HIV-1 Vpr amino acid sequence diversity and the tryptophan-kynurenine pathway as a potential mechanism for neurocognitive impairment

HIV infection compromises both the peripheral and central immune systems due to its pathogenic and neuropathogenic features. The mechanisms driving HIV-1 pathogenesis and neuropathogenesis involve a series of events, including metabolic dysregulation. Furthermore, HIV-subtype-specific variations, particularly alterations in the amino acid sequences of key viral proteins, are known to influence the severity of clinical outcomes in people living with HIV. However, the impact of amino acid sequence variations in specific viral proteins, such as Viral protein R (Vpr), on metabolites within the Tryptophan (Trp)-kynurenine (Kyn) pathway in people living with HIV remains unclear. Our research aimed to explore the relationship between variations in the Vpr amino acid sequence (specifically at positions 22, 41, 45, and 55, as these have been previously linked to neurocognitive function) and peripheral Trp-Kyn metabolites. Additionally, we sought to clarify the systems biology of Vpr sequence variation by examining the link between Trp-Kyn metabolism and peripheral inflammation, as a neuropathogenic mechanism. In this preliminary study, we analyzed a unique cohort of thirty-two (n = 32) South African cART naïve people living with HIV. We employed Sanger sequencing to ascertain blood-derived Vpr amino acid sequence variations and a targeted LC-MS/MS metabolomics platform to assess Trp-Kyn metabolites, such as Trp, Kyn, kynurenic acid (KA), and quinolinic acid (QUIN). Particle-enhanced turbidimetric assay and Enzyme-linked immunosorbent assays were used to measure immune markers, hsCRP, IL-6, suPAR, NGAL and sCD163. After applying Bonferroni corrections (p =.05/3) and adjusting for covariates (age and sex), only the Vpr G41 and A55 groups was nearing significance for higher levels of QUIN compared to the Vpr S41 and T55 groups, respectively (all p =.023). Multiple regression results revealed that Vpr amino acid variations at position 41 (adj R2 = 0.049, β = 0.505; p =.023), and 55 (adj R2 = 0.126, β = 0.444; p =.023) displayed significant associations with QUIN after adjusting for age and sex. Lastly, the higher QUIN levels observed in the Vpr G41 group were found to be correlated with suPAR (r =.588, p =.005). These results collectively underscore the importance of specific Vpr amino acid substitutions in influencing QUIN and inflammation (specifically suPAR levels), potentially contributing to our understanding of their roles in the pathogenesis and neuropathogenesis of HIV-1.

The relationship between HIV-1 neuroinflammation, neurocognitive impairment and encephalitis pathology: A systematic review of studies investigating post-mortem brain tissue

The activities of HIV-1 in the central nervous system (CNS) are responsible for a dysregulated neuroinflammatory response and the subsequent development of HIV-associated neurocognitive disorders (HAND). The use of post-mortem human brain tissue is pivotal for studying the neuroimmune mechanisms of CNS HIV infection. To date, numerous studies have investigated HIV-1-induced neuroinflammation in post-mortem brain tissue. However, from the commonly investigated studies in this line of research, it is not clear which neuroinflammatory markers are consistently associated with HIV neurocognitive impairment (NCI) and neuropathology (i.e., HIV-encephalitis, HIVE). Therefore, we conducted a systematic review of the association between neuroinflammation and NCI/HIVE from studies investigating post-mortem brain tissue. Our aim was to synthesise the published data to date to provide commentary on the most noteworthy markers that are associated with NCI/HIVE. PubMed, Scopus, and Web of Science databases were searched using a search protocol designed specifically for this study. Sixty-one studies were included that investigated the levels of inflammatory markers based on their gene and protein expression in association with NCI/HIVE. The findings revealed that the (1) transcript expressions of IL-1β and TNF-α were consistently associated with NCI/HIVE, whereas CCL2 and IL-6 were commonly not associated with NCI/HIVE, (2) protein expressions of CD14, CD16, CD68, Iba-1, IL-1β and TNF-α were consistently associated with NCI/HIVE, while CD45, GFAP, HLA-DR, IL-1 and IL-6 were commonly not associated with NCI/HIVE, and (3) gene and protein expressions of CNS IL-1β and TNF-α were consistently associated with NCI/HIVE, while IL-6 was consistently not associated with NCI/HIVE. These markers highlight the commonly investigated markers in this line of research and elucidates the neuroinflammatory mechanisms in the HIV-1 brain that are involved in the pathophysiology of NCI/HIVE. These markers and related pathways should be investigated for the development of improved diagnostics, prognostics, and therapeutics of HAND.

Neurocognitive deficits and socioeconomic risk factors among children and adolescents living with HIV in sub-Saharan Africa: a systematic review

INTRODUCTION

Children and adolescents living with HIV (C/ALHIV) are at a risk for significant neurocognitive deficits. There is limited literature that addresses the role of socioeconomic factors in neurocognitive deficits among CALHIV in Sub Saharan Africa (SSA), as it is very difficult to establish this causal relationship. Our systematic review was guided by the biodevelopmental framework that assumes that foundations of health and adversity affect later development and life outcomes. This systematic review aims to assess available evidence on the relationship between neurocognitive deficits and socioeconomic factors among HIV children and adolescents in SSA region.

METHOD

Using a pre-determined search strategy, we searched electronic databases including PubMed, web of Science and EBSCOhost (CINAHL and MEDLINE). Peer-reviewed publications that address neurocognitive deficits, psychosocial and socioeconomic risk factors among children and adolescents living with HIV in SSA were included in review.

RESULTS

Out of 640 articles, 17 studies from SSA met the inclusion criteria. Four studies reported no significant differences in the neurocognitive measures comparing children and adolescents with HIV infection to those uninfected. However, 10 studies suggest that C/ALHIV scored significantly low in general intellectual functions as compared to their uninfected peers. C/ALHIV were found to have substantial deficits in specific cognitive domains such as sequential processing, simultaneous processing, and learning. In addition, deficits in visuo-spatial processing, visual memory and semantic fluency were mentioned. Socioeconomic factors such as lower socioeconomic status (income, education and occupation), child orphanhood status and under-nutrition were linked with neurocognitive deficits.

CONCLUSION

Our findings suggest that CALHIV presented with poorer neurocognitive outcomes when compared to other populations which were associated with specific socioeconomic factors.

Antiretroviral choice and severe disease predict poorer neuropsychological outcomes in HIV+ children from Africa

BACKGROUND

The International Maternal Pediatric Adolescent AIDS Clinical Trials Network (IMPAACT) P1104s study evaluated neuropsychological outcomes over 96 weeks in children living with HIV (CLHIV) aged 5-11 years at 6 Sub-Saharan African sites to explore associations between HIV-illness related biomarkers and neuropsychological outcomes.

METHODS

Children living with HIV had participated in IMPAACT P1060, which compared efficacy of nevirapine versus lopinavir/ritonavir in children initiating ART at <3 years of age. At age 5-11, neuropsychological evaluations of KABC cognitive ability, TOVA attention-impulsivity and BOT-2 motor domains were assessed and repeated after 48 and 96 weeks. Clinical, antiretroviral therapy (ART) and laboratory (immunological and virological) parameters were used to predict neuropsychological outcomes using linear mixed-effects multivariable regression models, controlling for child and caregiver characteristics.

RESULTS

246 CLHIV (45% male, mean age at initial neuropsychological evaluation 7.1 yrs [SD 1.2]) began ART at a median age 14.9 months (IQR 8.2, 25.2). Nadir CD4 percentage was 14.7% (IQR 11.0, 19.5); the median peak viral load (VL) was 750 000 copies/ml (IQR 366 000, 750 000) and 63% had ≥WHO stage 3 clinical disease; 164 (67%) were on lopinavir/ritonavir, 71 (29%) were on nevirapine and 7 (3%) were on efavirenz. Other antiretrovirals were similar. Nevirapine at P1104s study start or later was associated with poorer neuropsychological scores across all domains except Global Executive Composite, even when controlling for nadir CD4 percent and time-varying HIV VL. Other predictors of poorer scores in KABC domains included low birth weight, WHO stage 4 disease and serious illness history and elevated VL was associated with worse BOT-2 scores.

CONCLUSION

Children receiving nevirapine had poorer neuropsychological scores than those on lopinavir/ritonavir. Antiretroviral choice might adversely impact neuropsychological performance. In addition, low birth weight and markers of severe HIV disease: advanced WHO clinical HIV disease, history of serious illness and an elevated VL, were associated with lower neuropsychological scores.

Immune Dysregulation Is Associated with Neurodevelopment and Neurocognitive Performance in HIV Pediatric Populations-A Scoping Review

HIV-1 is known for its complex interaction with the dysregulated immune system and is responsible for the development of neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. Considering that HIV-1-induced immune dysregulation and its association with neurodevelopmental and neurocognitive impairments in pediatric populations are not well understood, we conducted a scoping review on this topic. The study aimed to systematically review the association of blood and cerebrospinal fluid (CSF) immune markers with neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. PubMed, Scopus, and Web of Science databases were searched using a search protocol designed specifically for this study. Studies were selected based on a set eligibility criterion. Titles, abstracts, and full texts were assessed by two independent reviewers. Data from the selected studies were extracted and analyzed by two independent reviewers. Seven studies were considered eligible for use in this context, which included four cross-sectional and three longitudinal studies. An average of 130 (±70.61) children living with HIV, 138 (±65.37) children exposed to HIV but uninfected and 90 (±86.66) HIV-negative participants were included across the seven studies. Results indicate that blood and CSF immune markers are associated with neurocognitive development/performance in pediatric HIV populations. Only seven studies met the inclusion criteria, therefore, these limited the number of significant conclusions which could have been made by using such an approach. All considered, the evidence suggests that immune dysregulation, as in the case of adult HIV populations, also has a significant association with neurocognitive performance in pediatric HIV populations.

Plasma biomarker factors associated with neurodevelopmental outcomes in children with perinatal HIV infection and controlled viremia

OBJECTIVE

We examined relationships between plasma biomarkers and neurodevelopment in children from sub-Saharan Africa with perinatal HIV (PHIV) with controlled viremia on antiretroviral therapy (ART).

DESIGN

Longitudinal retrospective cohort study of children with controlled blood HIV replication.

METHODS

Children (N = 213; 57% girls) started ART at less than 3 years of age, had neurodevelopmental assessments (cognition, attention/impulsivity, motor proficiency, global executive functions) at 5-11 years, and achieved controlled viremia (HIV-1 RNA <400 copies/ml for ≥9 months before initial assessment). Twenty-three plasma biomarkers were measured at onset of controlled viremia, week 0 (first neurodevelopmental assessment), and week 48 (second neurodevelopmental assessment). Factor analysis was conducted at each time point. Multivariable linear regressions assessed associations between factors and neurodevelopmental scores.

RESULTS

Median age at week 0 was 7.0 years. Eighteen biomarkers loaded on six factors: a (L-10, IFNγ, IFNα2, IL-1β, IL-6, IP-10, TNFα); B (sCD163, sICAM-1, sVCAM-1, CRP); C (sE-selectin, sP-selectin); D [MIP-1β, vascular endothelial growth factor (VEGF)-A]; E (sCD14, CRP); and F (CX3CL1, MCP-1). Higher factor B scores were consistently associated with worse cognition and attention/impulsivity, and higher factor D scores with better attention/impulsivity.

CONCLUSION

These results suggest a detrimental effect of increased endothelial cell activation (sICAM-1, sVCAM-1) and monocyte/macrophage scavenger function (sCD163) and a beneficial effect of increased CCR5 ligand and HIV entry blocker MIP-1β and angiogenesis stimulant-VEGF concentrations on the neurodevelopment of children with PHIV. The model that emerges is of vascular inflammation leading to neurodevelopmental deficits. The role of persistent HIV replication in the central nervous system also needs to be further explored.

[Formula: see text]Neurodevelopmental assessment at one year of age predicts neuropsychological performance at six years in a cohort of West African Children

Rural children from Benin, west Africa were evaluated with the Mullen Scales of Early Learning (MSEL) at one year of age and then at six years with the Kaufman Assessment Battery for Children (KABC-II), the visual computerized Tests of Variables of Attention (TOVA), and the Bruininks-Oseretsky Test (BOT-2) of motor proficiency (N = 568). Although both the MSEL and KABC-II were available to the assessors in French, instructions to the mother/child were in local language of Fon. Mothers were evaluated with the Edinburgh Postpartum Depression Scale (EPDS), Caldwell HOME Scale, educational level and literacy, and a Socio-Economic Scale - also in their local language (Fon). After adjusting for maternal factors, MSEL cognitive composite was correlated with KABC-II with moderate effect sizes, but not with TOVA scores. Overall eta-squared effect for the multivariate models were moderately to strongly correlated (.07 to .37). Neurodevelopmental assessments in early childhood adapted cross-culturally are predictive of school-age neuropsychological cognitive ability.

Neurocognitive function among HIV-infected children on protease inhibitor -based versus non-protease inhibitor based antiretroviral therapy in Uganda: a pilot study

BACKGROUND

HIV infection is associated with significant neurocognitive deficits making maximization of cognitive function among children receiving antiretroviral therapy (ART) a public health imperative. Non-protease inhibitors (non-PIs) achieve higher drug levels in the cerebral spinal fluid (CSF) compared to PIs, potentially leading to better neurocognitive function by reducing CSF viral load and inflammation. ART that maximises children's neurodevelopment and school achievement could result in improved quality of life and productivity as adults, but little research to date has examined whether non-PI ART is associated with better neurocognitive outcomes. We compared the neurocognitive function between children living with HIV receiving PI-based and non PI-based ART.

METHODS

We recruited a consecutive sample of clinically stable Ugandan children living with HIV aged 5-12 years who received PI-based or non PI-based ART for ≥ 1 year (viral load < 1000 copies). Neurocognitive function was assessed using the Kaufman Assessment Battery for Children, the Test of Variables of Attention, and Bruininks-Oseretsky Test of Motor Proficiency. Age-adjusted neurocognitive z-scores for the two groups were compared using linear regression models in STATA version 13. The Hommel's method was used to adjust for multiple testing.

RESULTS

We enrolled 76 children living with HIV; 34 on PI ART and 42 on non-PI ART. Mean (±SD) age was greater in the non-PI vs. PI group (9.5 ± 1.9 vs. 8.5 ± 2.0) years (p = 0.03). Children in the non-PI group had lower socioeconomic scores (5.7 ± 3.3 vs. 7.4 ± 2.8, p = 0.02). There was no difference in neurocognitive function between the groups (adjusted p > 0.05) for KABC and TOVA. Children in the PI group had better total BOT scores than their counterparts (46.07 ± 1.40) vs. 40.51 (1.24), p = 0.03).

CONCLUSIONS

We detected no difference in neurocognitive function among children on PI and non PI-based ART therapy based on KABC and TOVA tests. Children on PI based ART had better motor function than their counterparts. We recommend a prospective study with a larger sample size.

Executive function in HIV-affected children and adolescents: a systematic review and meta-analyses

This review aimed to determine: whether EF is affected in children and adolescents (2-24-years-old) with perinatal HIV infection, perinatal HIV exposure without infection, and behaviourally acquired HIV. A systematic review (PROSPERO number: CRD42017067813) was conducted using 11 electronic databases (01.01.1981-09.07.2019) and 8 conference websites. Primary quantitative studies with EF scores on cognitive tasks and/or behavioural report measures were included. Meta-analyses were performed by EF subtype and subpopulations compared. 1789 records were found. Sixty-one studies were included in the narrative synthesis; 32 (N = 7884 participants) were included in meta-analyses. There was a distinct pattern of reduced EF in those with perinatal HIV infection on antiretroviral therapy compared to controls: pooled effect sizes were largest for verbal and visuospatial working memory, with smaller effects on planning, inhibitory control and set-shifting. Data were limited for other HIV-affected subpopulations. Perinatal HIV infection is associated with reduced EF with varying effect sizes for the different EF subtypes.

Opioid and neuroHIV Comorbidity - Current and Future Perspectives

With the current national opioid crisis, it is critical to examine the mechanisms underlying pathophysiologic interactions between human immunodeficiency virus (HIV) and opioids in the central nervous system (CNS). Recent advances in experimental models, methodology, and our understanding of disease processes at the molecular and cellular levels reveal opioid-HIV interactions with increasing clarity. However, despite the substantial new insight, the unique impact of opioids on the severity, progression, and prognosis of neuroHIV and HIV-associated neurocognitive disorders (HAND) are not fully understood. In this review, we explore, in detail, what is currently known about mechanisms underlying opioid interactions with HIV, with emphasis on individual HIV-1-expressed gene products at the molecular, cellular and systems levels. Furthermore, we review preclinical and clinical studies with a focus on key considerations when addressing questions of whether opioid-HIV interactive pathogenesis results in unique structural or functional deficits not seen with either disease alone. These considerations include, understanding the combined consequences of HIV-1 genetic variants, host variants, and μ-opioid receptor (MOR) and HIV chemokine co-receptor interactions on the comorbidity. Lastly, we present topics that need to be considered in the future to better understand the unique contributions of opioids to the pathophysiology of neuroHIV.

Graphical Abstract

Biomarkers of Inflammation Correlate With Clinical Scoring Indices in Human Immunodeficiency Virus-Infected Kenyans

Background

In high-income countries, inflammation has been associated with increased morbidity and mortality in human immunodeficiency virus (HIV)-infected individuals despite treatment with antiretroviral therapy (ART). However, these findings may not be generalizable to low-income settings.

Methods

In this cross-sectional study, multivariable linear regression was used to compare 28 inflammatory biomarker levels in HIV-infected and -uninfected participants. Correlations between biomarkers and Veterans Aging Cohort Study (VACS) index, Fibrosis-4 (FIB-4) score, and Framingham risk score were assessed.

Results

Plasma samples from 304 Kenyans were analyzed. Compared to HIV-uninfected controls, virologically suppressed HIV-infected participants had higher levels of CCL5, CXCL10, fatty acid binding protein (FABP) 2, fas ligand (FASLG), matrix metalloproteinase (MMP) 1, MMP7, soluble CD14 (sCD14), and soluble CD163 (sCD163) and lower MMP9 (P < .01). CD4+/HLA-DR+CD38+ (ρ = 0.32; P < .001), sCD14 (ρ = 0.25; P = .004), and sCD163 (ρ = 0.24; P = .006) were correlated with the VACS index. FABP2 was positively correlated (ρ = 0.29; P = .002), whereas MMP1 (ρ = -.32; P < .001) and MMP2 (ρ = -0.28; P = .002) were inversely correlated with the FIB-4 score.

Conclusions

Differences in biomarker levels exist between well-controlled HIV-infected participants on ART and uninfected controls. Some biomarkers are correlated to scoring indices predictive of morbidity and mortality. These biomarkers could serve as prognostic indicators and inform therapeutic development.

Association between caregiver depression symptoms and child executive functioning. Results from an observational study carried out in four sub-Saharan countries

Depressive symptoms among HIV-positive (HIV+) women may negatively impact their health and possibly that of their young children through risk of compromised caregiving. We evaluated how depression symptoms in predominantly (97%) female caregivers relate to neurodevelopmental outcomes in their HIV affected children. Data come from the IMPAACT P1104s Study, an observational cohort across six sites in four countries: Zimbabwe, South Africa, Uganda and Malawi. Participants (n = 611) were 5-11-year-old children with HIV (HIV), HIV exposed uninfected (HEU), or HIV unexposed uninfected (HUU). Primary caregivers were assessed for depression with the Hopkins Symptom Checklist (HSCL) and children with Behavior Rating Inventory for Executive Function (BRIEF) parent-report, Kauffman Assessment Battery for Children II (KABC), Bruininks-Oseretsky Test of Motor Proficiency 2nd Ed. (BOT-2), Test of Variables of Attention (TOVA), Multiple Indicators Cluster Survey, Child Disability and Development scales (MICS-4). Caregivers with higher depression scores (>1.75 mean HSCL score) reported more executive function problems in their children, regardless of HIV status. All executive function scores were significantly (p < 0.001) associated with depressive symptomatology at baseline and across time. Caregiver depressive symptomatology was not associated with other assessed neurocognitive outcomes. These results highlight the potential impact of caregiver depression on child behavioral outcomes.

Effect of HIV Subtype and Antiretroviral Therapy on HIV-Associated Neurocognitive Disorder Stage in Rakai, Uganda

BACKGROUND

Combination antiretroviral therapy (ART) improves HIV-associated neurocognitive disorder (HAND) stage in the United States where subtype B predominates, but the effect of ART and subtype on HAND stage in individuals in Uganda with subtypes D and A is largely unknown.

SETTING

A community-based cohort of participants residing in Rakai, Uganda.

METHODS

Three hundred ninety-nine initially ART-naive HIV-seropositive (HIV+) individuals were followed up over 2 years. Neurological and neuropsychological tests and functional assessments were used to determine HAND stage. Frequency and predictors of HAND and HIV-associated dementia (HAD) were assessed at baseline and at follow-up after ART initiation in 312 HIV+ individuals. HIV subtype was determined from gag and env sequences.

RESULTS

At 2-year follow-up, HAD frequency among HIV+ individuals on ART (n = 312) decreased from 13% to 5% (P < 0.001), but the overall frequency of HAND remained unchanged (56%-51%). Subtype D was associated with higher rates of impaired cognition (global deficit score ≥ 0.5) compared with HIV+ individuals with subtype A (55% vs. 24%) (P = 0.008). Factors associated with HAD at baseline were older age, depression, and plasma HIV viral load >100,000 copies/mL. At follow-up, age and depression remained significantly associated with HAD.

CONCLUSIONS

HIV+ individuals on ART in rural Uganda had a significant decrease in the frequency of HAD, but HAND persists after 2 years on ART. The current guideline of immediate ART initiation after HIV diagnosis is likely to greatly reduce HAD in sub-Saharan Africa. Further studies of the effect of HIV subtype and neurocognitive performance are warranted.

Neruodevelopmental Outcomes in Preschool Children Living With HIV-1 Subtypes A and D in Uganda

BACKGROUND

HIV is a neuropathogenic virus that may result in detrimental neurodevelopmental (ND) outcomes early in life. This is the first study to evaluate the effect of HIV-1 subtype on neurodevelopment of Ugandan preschool children.

METHODS

Neurodevelopment of 87 HIV-1 infected and 221 HIV exposed uninfected Ugandan children 1.8-4.9 years of age was assessed using 4 scales of the Mullen Scales of Early Learning (MSEL), 2 scales of the Color Object Association Test (COAT), and 1 score of the Early Childhood Vigilance Test. HIV-1 subtype was defined by phylogenetic analyses. General linear models were used to relate test scores to HIV-1 subtype (A versus D) while adjusting for relevant covariates. The scores were benchmarked against HIV exposed uninfected group to facilitate the interpretation.

RESULTS

Seventy-one percentage of children infected with subtype A versus 60% of children with subtype D were currently on antiretroviral therapy (P = 0.49). Children with HIV-1 subtype A infection were older when compared with subtype D (3.29 vs. 2.76 years, respectively, P = 0.03), but similar regarding sex, socioeconomic status, weight-for-age z-score, CD4+ and CD8+ (% and total), viral load. No statistically significant differences by HIV-1 subtype were observed in the MSEL, COAT and Early Childhood Vigilance Test. Differences ≥ 0.33 of the SD were observed for the MSEL Composite Score, Receptive Language (MSEL) and Total Memory (COAT).

CONCLUSIONS

In contrast to previously reported differences in ND outcomes of school-age children by HIV-1 subtype, ND scores among preschool children were similar for subtypes A and D, with few potential differences on language production and memory outcomes that favored subtype A. Further investigation with larger sample sizes and longitudinal follow-up is needed.

Effects of schooling on aspects of attention in rural Burkina Faso, West Africa

Background

We aimed to study the effects of schooling on aspects of attention using the Test of Variables of Attention (TOVA) among children in rural Burkina Faso.

Methods

We re-enrolled children of a previously community-based cluster randomized exclusive breastfeeding trial in rural Burkina Faso. A total of 534 children (280 boys and 254 girls) aged 6 to 8 years were assessed using the TOVA. We examined the effect size difference using Cohen’s d, ANOVA and conducted regression analyses.

Results

Forty nine percent of the children were in school. Children not in school performed poorly with a small effect size difference for ‘Response Time’, ‘Errors of omission’, and ‘Errors of commission’ compared to children in school. The effect size difference was moderate for ‘Response Time Variability’, and ‘D prime score’.

Conclusion

Schooling affects different aspects of attention in rural Burkina Faso. In settings where literacy and schooling rate is low, public sensitizations of the benefits of schooling need to be reinforced and advice on sending children to school need to be provided continuously.

Association between stunting and neuro-psychological outcomes among children in Burkina Faso, West Africa

BACKGROUND

In Burkina Faso, stunting affects children and is a public health problem. We studied the association between stunting and child's neuro-psychological outcomes at 6-8 years of age in rural Burkina Faso using the Kaufman Assessment Battery for Children, 2nd edition (KABC-II), the Children's Category Test 1 (CCT-1) and the Test of Variable of Attention (TOVA).

METHODS

We re-enrolled children of a previously community-based Exclusive breastfeeding trial in Burkina Faso. We assessed a total of 532 children aged 6-8 years using KABC-II for memory (Atlantis and Number Recall subtests), spatial abilities (Conceptual Thinking, Face Recognition and Triangle subtests), reasoning (Block Counting subtest), general cognition and CCT-1 for cognitive flexibility. A total 513 children were assessed using the TOVA to measure attention and inhibition. We calculated the Cohen's d to examine the effect size and conducted a linear regression to examine the association.

RESULTS

The proportion of stunting was 15.6% (83/532). Stunted children performed significantly poorer for memory (Atlantis and Number Recall), spatial abilities (Conceptual Thinking, Face Recognition and Triangle), general cognition and attention with a small effect size compared to non-stunted children. Children who were exposed scored significantly higher errors for cognitive flexibility and inhibition with a small effect size compared to unexposed children. At standardized and unstandardized multivariable regression analysis, stunted children performed significantly poorer for Atlantis (p = 0.001), Number Recall (p = 0.02), Conceptual Thinking (p = 0.01), Triangle (p = 0.001), general cognition (p ≤ 0.0001) and attention (p = 0.04) compared to non-stunted children. Children who were exposed scored significantly higher errors for cognitive flexibility (p = 0.02) and for inhibition (p = 0.02) compared to unexposed children. We adjusted all the results for age, schooling, sex, playing, father education, mother employment and promotion of previous exclusive breastfeeding.

CONCLUSION

Stunting is associated with poorer neuro-psychological outcomes among children in rural Burkina Faso. Initiatives related to prevention need to be established and advice on nutrition need to be provided.

Absence of neurocognitive disadvantage associated with paediatric HIV subtype A infection in children on antiretroviral therapy

Introduction

Infection with HIV subtype A has been associated with poorer neurocognitive outcomes compared to HIV subtype D in Ugandan children not eligible for antiretroviral therapy (ART). In this study, we sought to determine whether subtype‐specific differences are also observed among children receiving ART.

Materials and Methods

Children were recruited from a clinical trial in which they were randomized to receive either lopinavir (LPV)‐ or non‐nucleoside reverse transcriptase inhibitor (NNRTI)‐ based ART (NCT00978068). Age at initiation of ART ranged from six months to six years. HIV subtype was determined by PCR amplification and population sequencing of the pol region derived from peripheral blood mononuclear cell DNA, followed by application of the REGA and Recombinant Identification Programme algorithms. General cognition was assessed using the Kaufman Assessment Battery for Children (Second Edition), attention using the Test of Variables of Attention, and motor skills using the Bruininks‐Oseretsky Test of Motor Proficiency (Second Edition). Home environment was assessed using the Home Observation for the Measurement of the Environment (HOME). Age‐adjusted test z‐scores were entered into a regression model that adjusted for sex, socio‐economic status score, HOME score, years of schooling, and ART treatment type.

Results

One hundred and five children were tested; median (interquartile range) age was 7.05 years (6.30 to 8.44), CD4 count was 867.7 cells/mm³ (416.0 to 1203.5), and duration on ART was 4.03 years (3.55 to 4.23). Seventy‐eight children had HIV subtype A and 27 had subtype D; the groups had comparable home and socio‐economic status, except that there were more males among children infected with subtype A than D (64.7% vs. 35.3%, p = 0.02). There were no differences between the subtypes in general cognition (estimated mean difference: 0.20; 95% CI: −0.11 to 0.50); p = 0.21), attention (−0.18, 95% CI: −0.60 to 0.24, p = 0.41) and motor skills (1.60, 95% CI: −0.84 to 4.04, p = 0.20).

Conclusions

Our results imply that ART may diminish the neurocognitive disadvantage seen in treatment‐naïve HIV‐infected children with subtype A.

Neurocognitive functioning of HIV positive children attending the comprehensive care clinic at Kenyatta national hospital: exploring neurocognitive deficits and psychosocial risk factors

Children and adolescents are affected in different ways by HIV/AIDS. Neurocognitive deficits are one of the most significant long term effects on HIV infected children and adolescents. Several factors are thought to influence cognitive outcomes and this include immune status, Highly Active Antiretroviral Therapy (HAART), education and social support. The aim of the study was to assess the neurocognitive function of HIV infected children and adolescents and correlate it with psychosocial factors. A cross sectional study was carried out involving a sample of 90 children living with HIV between 8 and 15 years (M = 11.38, SD = 2.06) attending Comprehensive Care Clinic (CCC) at Kenyatta National Hospital (KNH). Samples were selected by using purposive sample technique. Kaufman Assessment Battery for Children-Second Edition was used to assess cognitive function and psychosocial issues were assessed using HEADS-ED. Data was analyzed using SPSS v23 and independent T-tests, Pearson's correlation and linear regression were used. The prevalence of neurocognitive deficits among HIV positive children attending CCC at KNH was 60% with neurocognitive performance of 54 children being at least 2SD below the mean based on the KABC-II scores. There was no significant correlation between mental processing index and CD4 count (Pearson's rho =  -0.01, p = 0.39). There was no significant association between Mental Processing Index and viral load (p = 0.056) and early ARV initiation (0.27). Using the HEADS-ED, risks factors related to education (β =  -5.67, p = 0.02) and activities and peer support (β =  -9.1, p = 0.002) were significantly associated with poor neurocognitive performance. Neurocognitive deficits are prevalent among HIV positive children attending CCC-KNH. This extent of the deficits was not associated with low CD4 count, high viral load or early initiation in HIV care. However, poor school performance and problem with peers was associated with poor neurocognitive performance.

Implications of Combined Exposure to Household Air Pollution and HIV on Neurocognition in Children

Air pollution exposure and HIV infection can each cause neurocognitive insult in children. The purpose of this study was to test whether children with combined high air pollution exposure and perinatal HIV infection have even greater risk of neurocognitive impairment. This was a cross-sectional study of HIV-uninfected unexposed (HUU) and HIV-infected children and their caregivers in Nairobi, Kenya. We used a detailed neuropsychological battery to evaluate neurocognitive functioning in several domains. We measured caregiver 24-h personal CO exposure as a proxy for child CO exposure and child urinary 1-hydroxypyrene (1-OHP), a biomarker for exposure to polycyclic aromatic hydrocarbons (PAHs). Median 24-h caregiver CO exposure was 6.1 and 3.7 ppm for 45 HIV-infected (mean age 6.6 years) and 49 HUU (mean age 6.7 years), respectively; 48.5% of HIV-infected and 38.6% of HUU had caregiver 24-h CO levels exceeding the WHO recommended level. Median 1-OHP exposure was 0.6 and 0.7 µmol/mol creatinine among HIV-infected and HUU children, respectively. HIV-infected children with high urinary 1-OHP (exceeding 0.68 µmol/mol creatinine) had significantly lower global cognition (p = 0.04), delayed memory (p = 0.01), and attention scores (p = 0.003). Among HUU children, urinary 1-OHP and caregiver 24-h caregiver CO were not significantly associated with neurocognitive function. Our findings suggest that combined chronic exposure to air pollutants and perinatal HIV infection may be associated with poorer neurocognitive outcomes. High prevalence of air pollution exposure highlights the need to reduce these exposures.

Neuropsychological performance in African children with HIV enrolled in a multisite antiretroviral clinical trial

OBJECTIVE AND DESIGN

Children with HIV infection (HIV+) are at neuropsychological risk, but few studies have evaluated this at multiple sites in low-income and middle-income countries. We compared neuropsychological outcomes at enrollment (>5 years age) among HIV+, HIV perinatally exposed uninfected (HEU), and HIV unexposed uninfected (HUU) children from four sub-Saharan countries.

METHODS

IMPAACT P1060 compared nevirapine versus lopinavir/ritonavir-based antiretroviral treatment (ART) in HIV-infected children 6-35 months of age. The present study (P1104s) enrolled P1060 children at 5-11 years of age and evaluated their neuropsychological performance over 2 years using the Kaufman Assessment Battery for Children, 2nd edition (KABC-II), Tests of Variables of Attention (TOVA), Bruininks-Oseretsky Test, 2nd edition (BOT-2), and parent-reported Behavior Rating Inventory of Executive Function (BRIEF). Cohorts were compared using generalized estimating equations least-squares means adjusted for site, child age and sex, and personal and social characteristics for child and caregiver.

RESULTS

Six hundred and eleven (246 HIV+, 183 HEU, 182 HUU) of the 615 enrolled at six sites [South Africa (three), Zimbabwe, Malawi, Uganda] were available for analysis. Mean age was 7.2 years, 48% male, 69% in school. Unadjusted and adjusted comparisons were consistent. HIV+ children performed significantly worse than HEU and HUU cohorts on all KABC-II cognitive performance domains and on BOT-2 total motor proficiency (P < 0.001), but not on the BRIEF Global Executive Indices. HUU and HEU cohorts were comparable on cognitive outcomes. HIV+ children initiated on ART before 1 year of age had significantly better BRIEF evaluations (lower scores - fewer behavior problems), compared with those started after (P = 0.03).

CONCLUSION

Significant cognitive deficits were documented among HIV+ children at school age, even when started on ART at an early age. Earlier HIV treatment, neuropsychological monitoring, and rehabilitative interventions are all needed. Subsequent testing for 2 more years will help further evaluate how HIV infection and exposure affect the developmental trajectory.

Maternal alcohol consumption during pregnancy and child's cognitive performance at 6-8 years of age in rural Burkina Faso: an observational study

Background

In Burkina Faso, it is not uncommon for mothers to drink alcohol, even during pregnancy. We aimed to study the association between maternal alcohol consumption during pregnancy and the child’s cognitive performance using the Kaufman Assessment Battery for Children, 2nd edition (KABC-II) and the Children’s Category Test Level 1 (CCT-1) in rural Burkina Faso.

Methods

We conducted a follow-up study of a community cluster-randomised Exclusive breastfeeding trial, and re-enrolled the children in rural Burkina Faso. A total of 518 children (268 boys and 250 girls) aged 6–8 years were assessed using the KABC-II and the CCT-1. We examined the effect size difference using Cohen’s d and conducted a linear regression analysis to examine the association.

Results

Self-reported alcohol consumption during pregnancy was 18.5% (96/518). Children whose mothers reported alcohol consumption during pregnancy performed significantly poorly for memory and spatial abilities tests from small effect size difference for ‘Atlantis’ (0.27) and ‘Triangle’ (0.29) to moderate effect size difference for ‘Number recall’ (0.72) compared to children whose mothers did not consume alcohol during pregnancy; the exposed children scored significantly higher errors with a small effect size (0.37) at problem solving (CCT-1) test compared to unexposed children.

At unstandardized and standardized multivariable analysis, children whose mothers reported alcohol consumption during pregnancy performed significantly poorer for memory-‘Atlantis’ (p = 0.03) and ‘Number recall’ (p = 0.0001), and spatial ability tests-‘Triangle’ (p = 0.03); they scored significantly higher errors at problem solving CCT-1 test (p = 0.002); all the results were adjusted for age, sex, schooling, stunting, father’s education, mother’s employment and the promotion of exclusive breastfeeding. No statistical association was found for visual abilities-‘Conceptual Thinking’, ‘Face recognition’, ‘Story completion’, and reasoning tests-‘Rover’, ‘Block counting’, and ‘Pattern Reasoning’.

Conclusion

Maternal alcohol consumption during pregnancy is associated with poorer cognitive performance for memory, spatial ability, and problem solving tests in the offspring in rural Burkina Faso. Futures studies needs to assess in more detail the maternal alcohol consumption patterns in Burkina Faso and possible preventive strategies.

Impact of HIV and Atiretroviral Therapy on Neurocognitive Outcomes Among School-Aged Children

INTRODUCTION

The impact of HIV infection and antiretroviral therapy (ART) on neurocognitive outcomes among children aged 7-14 years was assessed. We hypothesized that ART would ameliorate neurocognitive sequelae of HIV infection.

METHODS

HIV-positive and HIV-negative mother-child pairs from the Rakai Community Cohort Study and ART clinics in Rakai, Uganda, were followed prospectively for 4 years. Exposures were stratified as: perinatally HIV infected, perinatally HIV exposed but uninfected, and HIV unexposed and uninfected. The Kaufman Assessment Battery for Children assessed sequential and simultaneous processing, learning, planning, knowledge, and fluid crystalized index for overall functioning. Multivariable generalized linear models estimated adjusted prevalence rate ratios by age.

RESULTS

Of the 370 mother-child pairs, 55% were HIV unexposed and uninfected, 7% were perinatally HIV exposed but uninfected, and 37.9% were perinatally HIV infected. Among HIV-infected children, longer duration of ART was associated with a significant improvement of sequential processing skills (adjusted prevalence rate ratios 25-36 months: 0.55, 95% confidence interval [CI]: 0.34 to 0.9; 37-48 months: 0.39, 95% CI: 0.2 to 0.76; 49+ months: 0.23, 95% CI: 0.1 to 0.54). Each additional year of schooling was associated with a 30%-40% decrease of impairment for all neurocognitive measures assessed. Healthier children (higher age-standardized height and weight) had improved sequential and simultaneous processing and overall fluid crystalized index.

CONCLUSIONS

Sequential processing skills of working memory improved with prolonged ART, and increased duration of schooling was associated with a reduction of neurocognitive impairment. Early initiation and sustained use of ARTs and longer schooling are needed to reduce neurocognitive impairment among HIV-infected school-aged children.

Cross-cultural assessment of HIV-associated cognitive impairment using the Kaufman assessment battery for children: a systematic review

INTRODUCTION

Despite improved efficacy of, and access to, combination antiretroviral therapy (cART), HIV-associated cognitive impairments remain prevalent in both children and adults. Neuropsychological tests that detect such impairment can help clinicians formulate effective treatment plans. The Kaufman Assessment Battery for Children (KABC), although developed and standardized in the United States, is used frequently in many different countries and cultural contexts to assess paediatric performance across various cognitive domains. This systematic review investigated the cross-cultural utility of the original KABC, and its 2nd edition (KABC-II), in detecting HIV-associated cognitive impairment in children and adolescents.

METHODS

We entered relevant keywords and MeSH terms into the PubMed, PsycInfo, EBSCOHost, ProQuest, and Scopus databases, with search limits set from 1983-2017. Two independent reviewers evaluated the retrieved abstracts and manuscripts. Studies eligible for inclusion in the review were those that (a) used the KABC/KABC-II to assess cognitive function in children/adolescents aged 2-18 years, (b) featured a definition of cognitive impairment (e.g. >2 SD below the mean) or compared the performance of HIV-infected and uninfected control groups, and (c) used a sample excluded from population on which the instruments were normed.

RESULTS AND DISCUSSION

We identified nine studies (eight conducted in African countries, and one in the United Kingdom) to comprise the review's sample. All studies detected cognitive impairment in HIV-infected children, including those who were cART-naïve or who were cART treated and clinically stable. KABC/KABC-II subtests assessing simultaneous processing appeared most sensitive. Evaluation of the methodological quality of the selected studies by two independent reviews suggested that shortcomings included reporting and selection biases.

CONCLUSIONS

This systematic review provides evidence for the cross-cultural utility of the KABC/KABC-II, particularly the simultaneous processing subtests, in detecting cognitive impairment in HIV-infected children (including those who are clinically stable). Although the current results suggest there is justification for using the KABC/KABC-II primarily in East Africa, further investigation is required to explore the instrument's utility in other HIV-prevalent regions of the globe.

Neuroimaging abnormalities in clade C HIV are independent of Tat genetic diversity

Controversy remains regarding the neurotoxicity of clade C human immunodeficiency virus (HIV-C). When examined in preclinical studies, a cysteine to serine substitution in the C31 dicysteine motif of the HIV-C Tat protein (C31S) results in less severe brain injury compared to other viral clades. By contrast, patient cohort studies identify significant neuropsychological impairment among HIV-C individuals independent of Tat variability. The present study clarified this discrepancy by examining neuroimaging markers of brain integrity among HIV-C individuals with and without the Tat substitution. Thirty-seven HIV-C individuals with the Tat C31S substitution, 109 HIV-C individuals without the Tat substitution (C31C), and 34 HIV- controls underwent 3T structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Volumes were determined for the caudate, putamen, thalamus, corpus callosum, total gray matter, and total white matter. DTI metrics included fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD). Tracts of interest included the anterior thalamic radiation (ATR), cingulum bundle (CING), uncinate fasciculus (UNC), and corpus callosum (CC). HIV+ individuals exhibited smaller volumes in subcortical gray matter, total gray matter and total white matter compared to HIV- controls. HIV+ individuals also exhibited DTI abnormalities across multiple tracts compared to HIV- controls. By contrast, neither volumetric nor diffusion indices differed significantly between the Tat C31S and C31C groups. Tat C31S status is not a sufficient biomarker of HIV-related brain integrity in patient populations. Clinical attention directed at brain health is warranted for all HIV+ individuals, independent of Tat C31S or clade C status.

CNS Impact of Perinatal HIV Infection and Early Treatment: the Need for Behavioral Rehabilitative Interventions Along with Medical Treatment and Care

There is growing concern that although the more severe forms of HIV-associated neurologic deficits are reduced following highly active anti-retroviral therapy (HAART), mild to moderate cognitive disorders may persist for years after HAART initiation and this may occur despite complete plasma viral suppression. According to the UNAIDS 2014 report, there were 3.2 million children living with HIV around the world at the end of 2013 and 91 % of these resided in sub-Saharan Africa. In the same year, only 24 % of children who needed antiretroviral treatment (ART) received it and 190,000 children died of AIDS-related illnesses. We propose that behavioral interventions are needed in combination with medical treatment and care in order to fully address the needs of children and adolescents in Africa living with HIV. In early childhood, caregiver training programs to enhance the developmental milieu of the child with HIV can enhance their cognitive and social development and that such interventions are both feasible and well-accepted by the local population. For school-age children, computerized cognitive rehabilitation training can be an entertaining and engaging way to improve attention, working memory, and problem solving skills for children with HIV. Further dissemination and implementation science work is needed for arriving at cost-effective strategies for scaling up such behavioral interventions in African resource-constrained settings, given that the vast majority of HIV-affected children and youth worldwide presently live in sub-Saharan Africa.

HIV-Associated Cognitive Impairment in Perinatally Infected Children: A Meta-analysis

CONTEXT

Research shows, conclusively, that perinatal HIV infection has negative effects on cognitive functioning of children and adolescents. However, the extent of these cognitive impairments is unknown. Current literature does not document specific cognitive domains most affected in HIV-infected children and adolescents.

OBJECTIVE

To systematically review and meta-analyze the degree of cognitive impairment, and the specific cognitive domains affected, in children and adolescents with perinatally acquired HIV infection.

DATA SOURCES

We systematically searched 5 electronic bibliographic databases, namely: PubMed, PsychINFO, Academic Search Premier, Scopus, and WorldCat, by using a search protocol specifically designed for this study.

STUDY SELECTION

Studies were selected on the basis of set a priori eligibility criteria. Titles, abstracts, and full texts were assessed by 2 independent reviewers.

DATA EXTRACTION

Data from included studies were extracted into Microsoft Excel by 2 independent reviewers.

RESULTS

Twenty-two studies were identified for inclusion in the systematic review and of this, 6 studies were included in the meta-analysis. Results from the meta-analysis indicated that working memory and executive function were the domains most affected by the HIV virus.

LIMITATIONS

Only 27% of the included studies were suitable to enter into the meta-analysis. There was significant geographic bias in published studies, with only 32% (7/22) of included studies from sub-Saharan Africa.

CONCLUSIONS

The evidence supports an association between HIV infection in children and adolescents and cognitive impairment in the domains of working memory, executive function and processing speed, with effect size estimates also providing some support for deficits in visual memory and visual-spatial ability.

Rolling out Efavirenz for HIV Precision Medicine in Africa: Are We Ready for Pharmacovigilance and Tackling Neuropsychiatric Adverse Effects?

The introduction of antiretroviral therapy (ART) led to huge reductions in human immunodeficiency virus (HIV)-related deaths, turning HIV-infection into a chronic condition. Attention is now turning to quality of life for patients on lifelong ART treatment, reflecting on the safety of antiretroviral drugs. In sub-Saharan Africa, efavirenz (EFV) forms the preferred first-line ART but adverse drug events have also been reported. We express our concern on EFV-based regimens being part of mass rollout programs without full attention to toxicities. EFV is associated with various neuropsychiatric adverse events (AEs). If EFV use is not monitored, a huge burden of neuropsychiatric AEs and elevated risk of drug resistance due to nonadherence are likely to follow. A monumental EFV-based ART regimen rollout program, through the UNAIDS 90-90-90 and option B plus programs/approaches, is planned, which will more than double the number of patients on EFV-containing ART. According to this ambitious treatment target, by 2020, 90% of all people living with HIV will know their HIV status; 90% of all people with diagnosed HIV infection will receive sustained ART; and 90% of all people receiving ART will have viral suppression. On the other hand, HIV patients of African origin are predisposed to developing EFV-induced neuropsychiatric AEs due to specific CYP2B6 genetic variants causing impaired metabolism of EFV. It is our considered opinion that the potential quantitative and qualitative burden of EFV-induced neuropsychiatric AEs, which can vary from person-to-person and between populations, deserve special attention and action during the ART rollout program. We here make a case for Africa in particular where we project the burden of neuropsychiatric AEs to be greatest. We advocate for surveillance of neuropsychiatric AEs due to EFV therapy, incorporation of pharmacogenetics testing for CYP2B6 to assist in EFV dosing, and measurement of plasma EFV concentration, as a three-pronged rational therapeutic drug monitoring strategy to guide EFV treatment toward precision medicine.

A Randomized Controlled Trial to Evaluate if Computerized Cognitive Rehabilitation Improves Neurocognition in Ugandan Children with HIV

OBJECTIVES

Clinically stable children with HIV can have neuromotor, attention, memory, visual-spatial, and executive function impairments. We evaluated neuropsychological and behavioral benefits of computerized cognitive rehabilitation training (CCRT) in Ugandan HIV children.

DESIGN

One hundred fifty-nine rural Ugandan children with WHO Stage I or II HIV disease (6 to 12 years; 77 boys, 82 girls; M = 8.9, SD = 1.86 years) were randomized to one of three treatment arms over a 2-month period.

METHODS

The CCRT arm received 24 one-hour sessions over 2 months, using Captain's Log (BrainTrain Corporation) programmed for games targeting working memory, attention, and visual-spatial analysis. These games progressed in difficulty as the child's performance improved. The second arm was a "limited CCRT" with the same games rotated randomly from simple to moderate levels of training. The third arm was a passive control group receiving no training. All children were assessed at enrollment, 2 months (immediately following CCRT), and 3 months after CCRT completion.

RESULTS

The CCRT group had significantly greater gains through 3 months of follow-up compared to passive controls on overall Kaufman Assessment Battery for Children-second edition (KABC-II) mental processing index (p < .01), planning (p = .04), and knowledge (p = .03). The limited CCRT group performed better than controls on learning (p = .05). Both CCRT arms had significant improvements on CogState Groton maze learning (p < .01); although not on CogState attention/memory, TOVA/impulsivity, or behavior rating inventory for executive function and child behavior checklist (psychiatric behavior/symptom problems) ratings by caregiver.

CONCLUSIONS

CCRT intervention can be effective for neurocognitive rehabilitation in children with HIV in low-resource settings, especially in children who are clinically stable on ARV treatment.

Nutritional and Immunological Correlates of Memory and Neurocognitive Development Among HIV-Infected Children Living in Kayunga, Uganda

OBJECTIVE

To identify the nutritional and immunological correlates of memory and neurocognitive development as measured by the Mullen Scales of Early Learning (MSEL) and by the Color Object Association Test (COAT) among children in Uganda.

DESIGN

This analysis uses baseline data collected between 2008 and 2010 from 119 HIV-infected children aged 1-6 years, participating in a randomized controlled trial of an interventional parenting program in Kayunga, Uganda.

METHODS

Peripheral blood draws were performed to determine immunological biomarkers. Unadjusted and adjusted linear regression models were used to relate MSEL and COAT scores to sociodemographic characteristics, weight-for-age Z scores (WAZs), antiretroviral therapy status, and immunological biomarkers.

RESULTS

In the final analysis, 111 children were included. Lower levels of CD4 CD38 T cells (P = 0.04) were associated to higher immediate and total recall scores (P = 0.04). Higher levels of CD8 HLA-DR T cells were associated with higher total recall score (P = 0.04) of the COAT. Higher CD4 CD38 HLA-DR T cells levels were associated with higher gross motor scores of the MSEL (P = 0.02). WAZ was positively correlated to visual reception, fine motor, expressive language, and composite score of the MSEL.

CONCLUSIONS

Overall, WAZ was a stronger predictor of neurocognitive outcomes assessed by the MSEL. CD4 CD38 T cells were more specifically associated with memory-related outcomes. Future research should include immunological markers and standardized neurocognitive tests to further understand this relationship.

Lower sulfurtransferase detoxification rates of cyanide in konzo-A tropical spastic paralysis linked to cassava cyanogenic poisoning

Using a matched case-control design, we sought to determine whether the odds of konzo, a distinct spastic paraparesis associated with food (cassava) cyanogenic exposure in the tropics, were associated with lower cyanide detoxification rates (CDR) and malnutrition. Children with konzo (N=122, 5-17 years of age) were age- and sex-matched with presumably healthy controls (N=87) and assessed for motor and cognition performances, cyanogenic exposure, nutritional status, and cyanide detoxification rates (CDR). Cyanogenic exposure was ascertained by thiocyanate (SCN) concentrations in plasma (P-SCN) and urine (U-SCN). Children with a height-for-age z-score (HAZNCHS)<-2 were classified as nutritionally stunted. CDR was measured as time required to convert cyanide to SCN, and expressed as ms/μmol SCN/mg protein or as mmolSCN/ml plasma/min. Mean (SD) U-SCN in children with konzo was 521.9 (353.6) μmol/l and was, significantly higher than 384.6 (223.7) μmol/l in those without konzo. Conditional regression analysis of data for age- and sex- matched case-control pairs showed that konzo was associated with stunting (OR: 5.8; 95% CI: 2.7-12.8; p<0.01; N=83 paired groups) and higher U-SCN (OR: 1.1; 95% CI: 1.02-1.20 per 50-μmol increase in U-SCN; p=0.02; N=47 paired groups). After adjusting for stunting and U-SCN, the odds of developing konzo was reduced by 63% (95% CI: 11-85%, p=0.03; N=41 paired groups) for each 5mmol SCN/(ml plasma/min)-increase in CDR. Linear regression analysis indicated a significant association between BOT-2 or KABC-II scores and both the HAZNCHS z-score and the U-SCN concentration, but not the CDR. Our findings provide evidence in support of interventions to remove cyanogenic compounds from cassava prior to human consumption or, peharps, enhance the detoxification of cyanide in those relying on the cassava as the main source of food.

Biomedical risk, psychosocial influences, and developmental outcomes: lessons from the pediatric HIV population in Africa

Sub-Saharan Africa is home to millions of HIV-affected children. These children are likely to experience multiple developmental delays. In this chapter, I present data highlighting compromised neurobehavioral, mental health, and scholastic outcomes for children affected by HIV. Furthermore, I discuss biomedical factors (e.g., disease severity and nutritional status) that may exacerbate the adverse effects of HIV on childhood outcomes. I also present evidence on how psychosocial risk factors such as poor maternal mental health, orphanhood, and poverty may aggravate the effects of HIV. The concluding section of the chapter highlights conceptual and methodological refinements in research on the impact of HIV on child development in Sub-Saharan Africa.

Validation of the CogState battery for rapid neurocognitive assessment in Ugandan school age children

BACKGROUND

CogState is a widely used computer-based cognitive test whose validity has not been addressed in resource poor settings. We examined the construct, concurrent and convergent validity of CogState, test-retest reliability and the effect of sociodemographic variables on CogState outcomes in school age children.

METHODS

Two hundred and thirty Ugandan children (54% male) with mean age 6.99 years (SD = 1.67, range 5-13 years) were assessed using CogState, the Kaufman Assessment Battery for Children, 2nd edition (KABC-II) and the Test of Variables of Attention (TOVA) at baseline and 8 weeks later. Correlations were run between CogState and the KABC-II and TOVA to evaluate its concurrent and convergent validity. Factor analysis was used to evaluate construct validity of CogState. Correlations between baseline and 8 weeks CogState scores were used to determine the test-retest reliability while general linear models were used to assess associations with sociodemographic factors.

RESULTS

Significant correlations were observed between CogState's One Card Learning, One Back Memory and Card Detection with the TOVA and between CogState's Maze Chase and One Back Memory with KABC-II's Simultaneous Processing. CogState had a three factor structure with Processing Speed, Processing Accuracy and Maze Chase and Maze Learning. CogState had low to moderate test-retest reliability in Ugandan children with correlations ranging from 0.32 to 0.57. Age, sex and education were associated with CogState outcomes.

CONCLUSIONS

CogState is a valid and reliable test battery for rapid computer-based neurocognitive assessment in Ugandan children and can thus be used in this cultural context.

Immunological correlates of behavioral problems in school-aged children living with HIV in Kayunga, Uganda

BACKGROUND

HIV can affect the neuropsychological function of children, including their behavior. We aim to identify immunological correlates of behavioral problems among children living with HIV in Uganda.

METHODS

Children participating in a parent randomized control trial in Kayunga, Uganda were assessed with the Behavior Rating Inventory of Executive Function (BRIEF) and the Child Behavior Checklist (CBCL). We constructed simple and multiple linear regression models to identify immunological correlates of behavioral problems.

RESULTS

A total of 144 children living with HIV (50% male) with a mean age of 8.9 years [Standard Deviation (s.d.) = 1.9] were included in the analysis. Eighty-two children were on antiretroviral therapy. Mean CD4 cell count % was 35.1 cells/μl (s.d. = 15.0), mean CD4 cell activation 5.7% (s.d. = 5.1), mean CD8 cell activation was 17.5% (s.d. = 11.2) and 60 children (41.7%) had a viral load of <4000 copies/ml. In the adjusted models for the BRIEF, higher scores were associated with higher viral loads (aβ = 16.7 × 10-6, 95% CI -5.00 × 10-6 to 28.4 × 10-6), specifically on the behavioral regulation index. Higher mean CD8 activation % was associated with higher scores on the Externalizing Problems  and Total Problems  scales of the CBCL (aβ = 0.17, 95% CI 0.04-0.31 and aβ = 0.15, 95% CI 0.00-0.28, respectively).

CONCLUSIONS

Poorer behavioral outcomes were associated with higher viral loads while higher CD8 activation was associated with poorer emotional and behavioral outcomes. Complete immunological assessments for children living with HIV could include commonly used viral and immunological parameters to identify those at higher risk of having negative behavior outcomes and who would benefit the most from behavioral interventions.

Executive function and attention-deficit/hyperactivity disorder in Ugandan children with perinatal HIV exposure

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is among the most commonly diagnosed mental disorders in childhood and is associated with substantial deficits in executive functioning and lost academic and occupational attainment. This study evaluates symptoms of ADHD and their association with neurocognitive deficits in a cohort of rural Ugandan children who were born to HIV-infected mothers.

METHODS

We assessed ADHD symptoms and executive function (including memory and attention) in a non-clinical sample of children born to HIV-infected mothers in rural eastern Uganda. Analyses included assessments of the psychometric properties, factor structure, and convergent and discriminant validity of the ADHD measure (ADHD-Rating Scale-IV); and executive function deficits in children meeting symptom criteria for ADHD.

RESULTS

232 children [54% female; mean age 7.8 years (s.d. 2.0)] were assessed for ADHD and executive function deficits. The ADHD measure showed good internal consistency (α = 0.85.) Confirmatory factor analysis showed an acceptable fit for the diagnostic and statistical manual of mental disorders (DSM-5) two-factor model. Subjects meeting DSM-5 symptom criteria for ADHD had worse parent-rated executive function on six out of seven subscales.

CONCLUSIONS

Our results demonstrate structural validity of the ADHD measure with this population, strong associations between ADHD symptom severity and poorer executive function, and higher levels of executive function problems in perinatally HIV-exposed Ugandan children with ADHD. These findings suggest that ADHD may be an important neurocognitive disorder associated with executive function problems among children in sub-Saharan African settings where perinatal HIV exposure is common.

Neurocognitive functioning in a Romanian cohort of young adults with parenterally-acquired HIV-infection during childhood

The Romanian cohort can provide valuable information about the effect of chronic HIV-infection and exposure to combined antiretroviral therapy (cART) on the developing brain, based on its unique characteristics: young adults infected parenterally with HIV clade F in the late 1980s and exposed to cART for a decade. We conducted a prospective study using a neuropsychological test battery validated in other international HIV cohorts, in order to evaluate the rate and severity of neurocognitive impairment in a group of young Romanian adults. The 49 HIV-infected (HIV+) participants and the 20 HIV negative (HIV-) controls were similar for age and gender, although the HIV- group tended to be more educated. We found higher cognitive impairment prevalence in the HIV+ group (59.1 %) versus the HIV- group (10 %), and the impairment rate remained significantly higher even when the groups were matched based on the educational level (38.7 % for the HIV+ group vs. 10.0 % for the HIV- controls; p = 0.025). The nadir CD4 count was <200 in 71.4 % of patients, but at the time of neurocognitive assessment, 89.5 % of patients had normal immunological status and 81.8 % undetectable HIV load. Among the HIV-impaired group, 26 % of the participants had syndromic impairment while the other 74 % had asymptomatic neurocognitive impairment. We found a high prevalence of neurocognitive dysfunction in the Romanian young adults growing-up with HIV. The greatest HIV-related cognitive deficits were in the domains of executive and motor functioning, consistent with a frontosubcortical pattern.

HIV subtype is not associated with dementia among individuals with moderate and advanced immunosuppression in Kampala, Uganda

HIV-associated neurocognitive disorders (HAND) are a common neurological manifestation of HIV infection. A previous study suggested that HIV dementia may be more common among patients with subtype D virus than among those with subtype A virus among HIV+ individuals with advanced immunosuppression. We conducted a study to evaluate the frequency of HIV dementia, and the association of HIV dementia with HIV subtype and compartmentalization among HIV+ individuals with moderate and advanced immunosuppression (CD4 lymphocyte count >150 cells/μL and <250 cells/μL). The study enrolled 117 antiretroviral naïve HIV+ individuals in Kampala, Uganda. HIV+ individuals received neurological, neuropsychological testing, and functional assessments, and gag and gp41 regions were subtyped. Subjects were considered infected with a specific subtype if both regions analyzed were from the same subtype. 41% of the HIV+ individuals had HIV dementia (mean CD4 lymphocyte count = 233 cells/μL). 67 individuals had subtype A, 25 individuals had subtype D, 24 individuals were classified as A/D recombinants, and one individual had subtype C. There was no difference in the frequency of HIV dementia when stratified by HIV subtype A and D and no association with compartmentalization between the cerebrospinal fluid and peripheral blood. These results suggest that HIV dementia is common in HIV+ individuals in Uganda. There was no association between HIV subtype and dementia among HIV+ individuals with moderate and advanced immunosuppression. Future studies should be performed to confirm these results.

Effect of HIV clade differences on the onset and severity of HIV-associated neurocognitive disorders

The effects of evolutionary pressure on human immunodeficiency virus-1 (HIV) have resulted in a variety of clades and recombinants. The functional implications of HIV clades on disease onset and progression of HIV-associated neurocognitive disorders (HAND) have been suggested by clinical and basic science studies, which will be reviewed in detail. Some clinical studies suggest that patients infected with clade D show the greatest propensity for developing HIV-associated dementia (HAD) followed by clades B, C, and A, respectively. However, there are conflicting reports. This review summarizes clinical studies that have assessed behavioral abnormalities and HIV clade type in HAND patients, focusing on the clades stated above. The limitations include variations in testing used to define the cohorts, patient sample size, lack of HIV clade characterization, combination antiretroviral therapy (cART) availability, and other factors, which are highlighted and compared between clinical studies performed primarily in Africa and India. Basic science studies provide substantial evidence that HIV clade differences can result in varying degrees of neuropathology and are also reviewed in some detail. These studies indicate that there are a number of clade differences, most notably in Tat, that result in different degrees of neurovirulence or neuropathological effects in vitro and in a mouse model of HAND. In order to confirm the hypothesis that HIV clade differences are important determinants of HAND pathogenesis, larger, longitudinal studies that employ standard definitions of HAND and HIV clade testing must be performed. In a larger sense, HAND continues to be highly prevalent despite the advent of cART, and therefore, further studies into HAND pathogenesis are critical to develop better therapies.

The Bruininks-Oseretsky Test of Motor Proficiency-Short Form is reliable in children living in remote Australian Aboriginal communities

Background

The Lililwan Project is the first population-based study to determine Fetal Alcohol Spectrum Disorders (FASD) prevalence in Australia and was conducted in the remote Fitzroy Valley in North Western Australia. The diagnostic process for FASD requires accurate assessment of gross and fine motor functioning using standardised cut-offs for impairment. The Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (BOT-2) is a norm-referenced assessment of motor function used worldwide and in FASD clinics in North America. It is available in a Complete Form with 53 items or a Short Form with 14 items. Its reliability in measuring motor performance in children exposed to alcohol in utero or living in remote Australian Aboriginal communities is unknown.

Methods

A prospective inter-rater and test-retest reliability study was conducted using the BOT-2 Short Form. A convenience sample of children (n = 30) aged 7 to 9 years participating in the Lililwan Project cohort (n = 108) study, completed the reliability study. Over 50% of mothers of Lililwan Project children drank alcohol during pregnancy. Two raters simultaneously scoring each child determined inter-rater reliability. Test-retest reliability was determined by assessing each child on a second occasion using predominantly the same rater. Reliability was analysed by calculating Intra-Class correlation Coefficients, ICC(2,1), Percentage Exact Agreement (PEA) and Percentage Close Agreement (PCA) and measures of Minimal Detectable Change (MDC) were calculated.

Results

Thirty Aboriginal children (18 male, 12 female: mean age 8.8 years) were assessed at eight remote Fitzroy Valley communities. The inter-rater reliability for the BOT-2 Short Form score sheet outcomes ranged from 0.88 (95%CI, 0.77 – 0.94) to 0.92 (95%CI, 0.84 – 0.96) indicating excellent reliability. The test-retest reliability (median interval between tests being 45.5 days) for the BOT-2 Short Form score sheet outcomes ranged from 0.62 (95%CI, 0.34 – 0.80) to 0.73 (95%CI, 0.50 – 0.86) indicating fair to good reliability. The raw score MDC was 6.12.

Conclusion

The BOT-2 Short Form has acceptable reliability for use in remote Australian Aboriginal communities and will be useful in determining motor deficits in children exposed to alcohol prenatally. This is the first known study evaluating the reliability of the BOT-2 Short Form, either in the context of assessment for FASD or in Aboriginal children.

Neurodevelopment in perinatally HIV-infected children: a concern for adolescence

Globally, an estimated 3.4 million children are living with HIV, yet little is known about the effects of HIV and antiretroviral treatment (ART) on the developing brain, and the neurodevelopmental and behavioural outcomes of perinatally HIV-infected (PHIV+) adolescents. We reviewed the literature on neurodevelopmental outcomes in PHIV+ children and adolescents, and summarized the current evidence on behaviour, general cognition, specific domains, hearing and language, school performance and physical disabilities due to neurological problems. Evidence suggests that PHIV+ children do not perform as well as controls on general cognitive tests, processing speed and visual-spatial tasks, and are at much higher risk for psychiatric and mental health problems. Children with AIDS-defining diagnoses are particularly at risk for poorer outcomes. A striking finding is the lack of published data specific to the adolescent age group (10-25 years), particularly from resource-constrained countries, which have the highest HIV prevalence. In addition, extreme heterogeneity in terms of timing and source of infection, and antiretroviral experience limits our ability to summarize findings of studies and generalize results to other settings. Due to the complex nature of the developing adolescent brain, environmental influences and variation in access to ART, there is an urgent need for research on the longitudinal trajectory of neurodevelopment among children and adolescents perinatally infected with HIV, especially in high burden resource-constrained settings.

Neuropsychological effects of konzo: a neuromotor disease associated with poorly processed cassava

BACKGROUND

Konzo is an irreversible upper-motor neuron disorder affecting children dependent on bitter cassava for food. Although the neuroepidemiology of konzo is well characterized, we report the first neuropsychological findings.

METHOD

Children with konzo in the Democratic Republic of Congo (mean age 8.7 years) were compared with children without konzo (mean age 9.1 years) on the Kaufman Assessment Battery for Children, second edition (KABC-II), and the Bruininks-Oseretsky Test of Motor Proficiency, second edition (BOT-2). Both groups were also compared with normative KABC measures from earlier studies in a nearby nonkonzo region.

RESULTS

Using a Kruskal-Wallis test, children with konzo did worse on the KABC-II simultaneous processing (visual-spatial analysis) (K [1] = 8.78, P = .003) and mental processing index (MPI) (K [1] = 4.56, P = .03) than children without konzo. Both konzo and nonkonzo groups had poorer KABC sequential processing (memory) and MPI relative to the normative group from a nonkonzo region (K [2] = 75.55, P < .001). Children with konzo were lower on BOT-2 total (K [1] = 83.26, P < .001). KABC-II MPI and BOT-2 total were predictive of konzo status in a binary logistic regression model: odds ratio = 1.41, P < .013; 95% confidence interval 1.13-1.69.

CONCLUSIONS

Motor proficiency is dramatically affected, and both children with and without konzo have impaired neurocognition compared with control children from a nonoutbreak area. This may evidence a subclinical neurocognitive form of the disease, extending the human burden of konzo with dramatic public health implications.

Global NeuroAIDS roundtable

In May 2012, the Division of AIDS Research at the National Institute of Mental Health (NIMH) organized the "Global NeuroAIDS Roundtable" in conjunction with the 11th International Symposium on Neurovirology and the 2012 Conference on HIV in the Nervous System. The meeting was held in New York, NY, USA and brought together NIMH-funded investigators who are currently working on projects related to the neurological complications of AIDS (NeuroAIDS) in Africa, Asia, Eastern Europe, and Latin America in order to provide an opportunity to share their recent findings and discuss the challenges encountered within each country. The major goals of the roundtable were to evaluate HIV-associated neurocognitive impairment and determine if it may be directly attributable to distinct HIV subtypes or clades and to discuss the future priorities for global NeuroAIDS research. At the "Global NeuroAIDS Roundtable", presentations of preliminary research indicated that HIV-associated neurocognitive impairment is prevalent in all countries examined regardless of which HIV clade is present in the region. The only clear-cut difference between HIV-1 clades was in relation to subtypes A and D in Uganda. However, a key point that emerged from the discussions was that there is an urgent need to standardize neurocognitive assessment methodologies across the globe before definitive conclusions can be drawn regarding the relationship between HIV clade diversity and neuropathogenesis. Future research directions were also discussed at the roundtable with particular emphasis on the potential of viral and host factor molecular interactions to impact the pathophysiology of HIV-associated neurocognitive disorders (HAND) from a global perspective.

Enrichment of HIV-1 subtype AD recombinants in a Ugandan cohort of severely septic patients

Background

Several population-wide HIV-1 subtype distribution studies in Uganda have evaluated relatively healthy clinic patients. Given the differences in HIV-1 disease progression based on subtype, we examined HIV-1 subtype distribution and disease outcomes among hospitalized patients with severe sepsis.

Methods

Patients with severe sepsis were enrolled at two hospitals in Uganda. Data collected included demographics, Karnofsky scores, highly active antiretroviral therapy (HAART) use, HIV-1 serostatus, CD4+ T cell concentration, whole blood lactate concentration, and blood cultures. HIV-1 subtypes were determined by sequencing parts of the gag and env genes, followed by phylogenetic analysis.

Results

Of the 267 patients evaluated, 228 (85.4%) were HIV infected. The predominant HIV-1 subtypes were A (46%), D (17%), and AD recombinants (30%). HIV-1 subtypes B, C, and other recombinants were uncommon. Patients infected with HIV-1 subtypes A, D and AD viruses were similar in demographics, CD4⁺ T cell concentration, HAART use, Karnofsky scores, whole blood lactate concentration, and positive blood cultures. There was no difference in 30-day mortality from severe sepsis between the 3 groups (p = 0.99).

Conclusion

A high proportion of HIV-1 subtypes A and AD recombinants was observed in this cohort of severely septic patients. The proportion of AD recombinants was higher in this cohort than in previous cohorts of Ugandan HIV-1 patients. No difference in baseline demographics, clinical factors or 30-day mortality was seen across HIV-subtypes.

Global analysis of sequence diversity within HIV-1 subtypes across geographic regions

AIMS: HIV-1 sequence diversity can affect host immune responses and phenotypic characteristics such as antiretroviral drug resistance. Current HIV-1 sequence diversity classification uses phylogeny-based methods to identify subtypes and recombinants, which may overlook distinct subpopulations within subtypes. While local epidemic studies have characterized sequence-level clustering within subtypes using phylogeny, identification of new genotype - phenotype associations are based on mutational correlations at individual sequence positions. We perform a systematic, global analysis of position-specific pol gene sequence variation across geographic regions within HIV-1 subtypes to characterize subpopulation differences that may be missed by standard subtyping methods and sequence-level phylogenetic clustering analyses. MATERIALS #ENTITYSTARTX00026; METHODS: Analysis was performed on a large, globally diverse, cross-sectional pol sequence dataset. Sequences were partitioned into subtypes and geographic subpopulations within subtypes. For each subtype, we identified positions that varied according to geography using VESPA (viral epidemiology signature pattern analysis) to identify sequence signature differences and a likelihood ratio test adjusted for multiple comparisons to characterize differences in amino acid (AA) frequencies, including minority mutations. Synonymous nonsynonymous analysis program (SNAP) was used to explore the role of evolutionary selection witihin subtype C. RESULTS: In 7693 protease (PR) and reverse transcriptase (RT) sequences from untreated patients in multiple geographic regions, 11 PR and 11 RT positions exhibited sequence signature differences within subtypes. Thirty six PR and 80 RT positions exhibited within-subtype geography-dependent differences in AA distributions, including minority mutations, at both conserved and variable loci. Among subtype C samples from India and South Africa, nine PR and nine RT positions had significantly different AA distributions, including one PR and five RT positions that differed in consensus AA between regions. A selection analysis of subtype C using SNAP demonstrated that estimated rates of nonsynonymous and synonymous mutations are consistent with the possibility of positive selection across geographic subpopulations within subtypes. CONCLUSION: We characterized systematic genotypic pol differences across geographic regions within subtypes that are not captured by the subtyping nomenclature. Awareness of such differences may improve the interpretation of future studies determining the phenotypic consequences of genetic backgrounds.

Neurocognitive and motor deficits in HIV-infected Ugandan children with high CD4 cell counts

BACKGROUND

Human immunodeficiency virus (HIV) infection causes neurocognitive or motor function deficits in children with advanced disease, but it is unclear whether children with CD4 cell measures above the World Health Organization (WHO) thresholds for antiretroviral therapy (ART) initiation suffer significant impairment.

METHODS

The neurocognitive and motor functions of HIV-infected ART-naive Ugandan children aged 6-12 years with CD4 cell counts of >350 cells/μL and CD4 cell percentage of >15% were compared with those of HIV-uninfected children, using the Test of Variables of Attention (TOVA), the Kaufman Assessment Battery for Children, second edition (KABC-2), and the Bruininks-Oseretsky Test of Motor Proficiency, second edition (BOT-2).

RESULTS

Ninety-three HIV-infected children (median CD4 cell count, 655 cells/μL; plasma HIV RNA level, 4.7 log(10) copies/mL) were compared to 106 HIV-uninfected children. HIV-infected children performed worse on TOVA visual reaction times (multivariate analysis of covariance; P = .006); KABC-2 sequential processing (P = .005), simultaneous processing (P = .039), planning/reasoning (P = .023), and global performance (P = .024); and BOT-2 total motor proficiency (P = .003). High plasma HIV RNA level was associated with worse performance in 10 cognitive measures and 3 motor measures. In analysis of only WHO clinical stage 1 or 2 HIV-infected children (n = 68), significant differences between the HIV-infected and HIV-uninfected groups (P < .05) remained for KABC-2 sequential processing, KABC-2 planning/reasoning, and BOT-2 motor proficiency.

CONCLUSIONS

Significant motor and cognitive deficits were found in HIV-infected ART-naive Ugandan children with CD4 cell counts of ∼350 cells/μL and percentages of >15%. Study of whether early initiation of ART could prevent or reverse such deficits is needed.

Single nucleotide polymorphism in gene encoding transcription factor Prep1 is associated with HIV-1-associated dementia

Background

Infection with HIV-1 may result in severe cognitive and motor impairment, referred to as HIV-1-associated dementia (HAD). While its prevalence has dropped significantly in the era of combination antiretroviral therapy, milder neurocognitive disorders persist with a high prevalence. To identify additional therapeutic targets for treating HIV-associated neurocognitive disorders, several candidate gene polymorphisms have been evaluated, but few have been replicated across multiple studies.

Methods

We here tested 7 candidate gene polymorphisms for association with HAD in a case-control study consisting of 86 HAD cases and 246 non-HAD AIDS patients as controls. Since infected monocytes and macrophages are thought to play an important role in the infection of the brain, 5 recently identified single nucleotide polymorphisms (SNPs) affecting HIV-1 replication in macrophages in vitro were also tested.

Results

The CCR5 wt/Δ32 genotype was only associated with HAD in individuals who developed AIDS prior to 1991, in agreement with the observed fading effect of this genotype on viral load set point. A significant difference in genotype distribution among all cases and controls irrespective of year of AIDS diagnosis was found only for a SNP in candidate gene PREP1 (p = 1.2×10⁻⁵). Prep1 has recently been identified as a transcription factor preferentially binding the −2,518 G allele in the promoter of the gene encoding MCP-1, a protein with a well established role in the etiology of HAD.

Conclusion

These results support previous findings suggesting an important role for MCP-1 in the onset of HIV-1-associated neurocognitive disorders.

Drug resistance prevalence and HIV-1 variant characterization in the naive and pretreated HIV-1-infected paediatric population in Madrid, Spain

BACKGROUND

Drug resistance mutations affect antiretroviral therapy (ART) effectiveness in HIV-1-infected children, compromising long-term therapy. HIV-1 variants and drug resistance mutations were identified in HIV-infected children from Madrid, Spain.

METHODS

Patients from the Madrid cohort of HIV-infected children (1993-2009) with available pol sequences or infected samples stored at the Spanish HIV-1 BioBank were selected. Specimens were used to perform new pol sequences when not available. HIV-1 variants were characterized by phylogenetic analysis. Resistance mutations were identified according to the International AIDS Society-USA list (2009).

RESULTS

In 198 patients, pol sequences were recovered from routine resistance testing (n = 98) or newly performed using stored plasma, lymphocytes or DNA (n = 100). Patients were mostly Europeans (90%), with moderate to severe AIDS symptoms (65%), on ART (85%) when the specimen was sequenced and infected by subtype B (90%). Among the 19 HIV-1 non-B variants found, 58% were recombinants (8CRF02_AG, 1CRF08_BC, 1CRF12_BF and 1CRF13_cpx) and the rest were 'pure' non-B subtypes (1A2, 2C, 2D, 1F1, 1G and 1H). Transmitted drug resistance (TDR) mutations were detected in 13% of naive children; 4%, 7% and 10% for protease inhibitors (PIs), nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), respectively. Global resistance prevalence was higher (66%) among ART-exposed children; 37% for PIs, 54% for NRTIs and 35% for NNRTIs.

CONCLUSIONS

HIV-1 non-B variants infected 10% of the cohort during 1993-2009. Resistant viruses were present in 26.5% and 66% of naive and pretreated children, respectively. Our data suggest that TDR prevalence in children could be higher than that reported in adults in Spain. The provided data will help to improve clinical management of HIV-infected children in Spain.

HIV-1 infection and cognitive impairment in the cART era: a review

With the introduction of combination antiretroviral therapy AIDS dementia complex or HIV-associated dementia, as it was termed later, largely disappeared in clinical practice. However, in the past few years, patients, long-term infected and treated, including those with systemically well controlled infection, started to complain about milder memory problems and slowness, difficulties in concentration, planning, and multitasking. Neuropsychological studies have confirmed that cognitive impairment occurs in a substantial (15-50%) proportion of patients. Among HIV-1-infected patients cognitive impairment was and is one of the most feared complications of HIV-1 infection. In addition, neurocognitive impairment may affect adherence to treatment and ultimately result in increased morbidity for systemic disease. So what may be going on in the CNS after so many years of apparently controlled HIV-1 infection is an urgent and important challenge in the field of HIV medicine. In this review we summarize the key currently available data. We describe the clinical neurological and neuropsychological findings, the preferred diagnostic approach with new imaging techniques and cerebrospinal fluid analysis. We try to integrate data on pathogenesis and finally discuss possible therapeutic interventions.