Developmental outcomes in Malawian children with retinopathy-positive cerebral malaria

Is Neurodevelopmental Assessment in Early Childhood Predictive of Performance Assessed Later in Childhood and Adolescence in Sub-Saharan Africa? A Systematic Review of the Literature

BACKGROUND

Most neurodevelopmental tests used to assess child development in sub-Saharan Africa were developed in western or high-income countries, raising the question of their usefulness with African children.

OBJECTIVE

This systematic review identified and synthesized key findings from studies measuring development in children in Sub-Saharan Africa in early childhood and again at school age, to assess neurocognitive associations longitudinally from infancy through middle childhood.

METHODS

The study was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method, selecting articles referenced in the PubMed, PsycInfo, and Embase databases using the following inclusion criteria: published between 2000 and 2022, written in French or English, and presenting results dealing with the objective assessment of child's neurodevelopment. All articles were registered in the Zotero reference manager and analyzed by title, abstract, and full text.

RESULTS

Several of the seven selected studies confirmed that attention and working memory in infancy can predict children's neurocognitive performance, including mathematical ability, at school age. In two of the studies, children with poor mental development at 1 year of age are more likely to present with poorer behavioral development at school age, including learning difficulties in school and risk for grade repetition.

CONCLUSION

Cognitive ability assessed in early childhood is strongly associated with performance at school age in cohorts of African children followed longitudinally. Even with assessments adapted cross-culturally, infants and preschoolers at risk for poor developmental outcomes can be identified to better receive strategic early interventions to enhance their development.

Severe malaria-related disability in African children: a scoping review

PURPOSE

Disability is a consequence of severe malaria for a significant proportion of African children. This scoping review aims to describe the impact of severe malaria on African children according to current literature using an international biopsychical classification and framework of disability and functioning.

MATERIALS AND METHODS

MEDLINE, EMBASE, Global Health, and CINHAL databases were searched for original research conducted on African children aged 0-18 using terms related to severe malaria and components of disability. Independent and dependent variables were extracted and classified using the World Health Organization's International Classification of Functioning, Disability, and Health-Children and Youth version (ICF-CY) using standardized coding methods.

RESULTS

Seventy-two percent of the measured variables in the 34 included studies were coded as "body functions," (i.e., impairments), such as mental, neuromusculoskeletal, movement, and sensory functions, and 23.3% of variables were coded as "activities and participation" (i.e., activity limitations/participation restrictions), such as difficulties with general tasks and demands, communication, mobility, interpersonal interactions, and relationships. "Environment" variables such as family support, health access, education, or societal attitudes were not found in the included studies.

CONCLUSIONS

Existing peer-reviewed quantitative research of severe malaria-related disability is focused on neurological sequelae, with less research about activity limitations and participation restrictions.

Admission Clinical and EEG Features Associated With Mortality and Long-term Neurologic and Cognitive Outcomes in Pediatric Cerebral Malaria

BACKGROUND AND OBJECTIVES

For children with cerebral malaria, mortality is high, and in survivors, long-term neurologic and cognitive dysfunctions are common. While specific clinical factors are associated with death or long-term neurocognitive morbidity in cerebral malaria, the association of EEG features with these outcomes, particularly neurocognitive outcomes, is less well characterized.

METHODS

In this prospective cohort study of 149 children age 6 months to 12 years who survived cerebral malaria in Kampala, Uganda, we evaluated whether depth of coma, number of clinical seizures, or EEG features during hospitalization were associated with mortality during hospitalization, short-term and long-term neurologic deficits, or long-term cognitive outcomes (overall cognition, attention, memory) over the 2-year follow-up.

RESULTS

Higher Blantyre or Glasgow Coma Scores (BCS and GCS, respectively), higher background voltage, and presence of normal reactivity on EEG were each associated with lower mortality. Among clinical and EEG features, the presence of >4 seizures on admission had the best combination of negative and positive predictive values for neurologic deficits in follow-up. In multivariable modeling of cognitive outcomes, the number of seizures and specific EEG features showed independent association with better outcomes. In children younger than 5 years throughout the study, seizure number and presence of vertex sharp waves were independently associated with better posthospitalization cognitive performance, faster dominant frequency with better attention, and higher average background voltage and faster dominant background frequency with better associative memory. In children younger than 5 years at CM episode but 5 years or older at cognitive testing, seizure number, background dominant frequency, and the presence of vertex sharp waves were each associated with changes in cognition, seizure number and variability with attention, and seizure number with working memory.

DISCUSSION

In children with cerebral malaria, seizure number is strongly associated with the risk of long-term neurologic deficits, while seizure number and specific EEG features (average background voltage, dominant rhythm frequency, presence of vertex sharp waves, presence of variability) are independently associated with cognitive outcomes. Future studies should evaluate the predictive value of these findings.

Association of severe malaria with cognitive and behavioural outcomes in low- and middle-income countries: a meta-analysis and systematic review

BACKGROUND

Malaria affects 24 million children globally, resulting in nearly 500,000 child deaths annually in low- and middle-income countries (LMICs). Recent studies have provided evidence that severe malaria infection results in sustained impairment in cognition and behaviour among young children; however, a formal meta-analysis has not been published. The objective was to assess the association between severe malaria infection with cognitive and behavioural outcomes among children living in LMICs.

METHODS

Six online bibliographic databases were searched and reviewed in November 2022. Studies included involved children < 18 years of age living in LMICs with active or past severe malaria infection and measured cognitive and/or behaviour outcomes. The quality of studies was assessed. Definitions of severe malaria included cerebral malaria, severe malarial anaemia, and author-defined severe malaria. Results from all studies were qualitatively summarized. For studies with relevant data on attention, learning, memory, language, internalizing behaviour and externalizing behaviour, results were pooled and a meta-analysis was performed. A random-effects model was used across included cohorts, yielding a standardized mean difference between the severe malaria group and control group.

RESULTS

Out of 3,803 initial records meeting the search criteria, 24 studies were included in the review, with data from 14 studies eligible for meta-analysis inclusion. Studies across sub-Saharan Africa assessed 11 cohorts of children from pre-school to school age. Of all the studies, composite measures of cognition were the most affected areas of development. Overall, attention, memory, and behavioural problems were domains most commonly found to have lower scores in children with severe malaria. Meta-analysis revealed that children with severe malaria had worse scores compared to children without malaria in attention (standardized mean difference (SMD) -0.68, 95% CI -1.26 to -0.10), memory (SMD -0.52, 95% CI -0.99 to -0.06), and externalizing behavioural problems (SMD 0.45, 95% CI 0.13-0.78).

CONCLUSION

Severe malaria is associated with worse neuropsychological outcomes for children living in LMICs, specifically in attention, memory, and externalizing behaviours. More research is needed to identify the long-term implications of these findings. Further interventions are needed to prevent cognitive and behavioural problems after severe malaria infection.

TRIAL REGISTRATION

This systematic review was registered under PROSPERO: CRD42020154777.

Clinical aspects of malarial retinopathy: a critical review

This review will provide a better understanding of a set of signs known as malarial retinopathy. The discovery of this retinopathy in association with cerebral malaria is important because it best distinguishes patients with true cerebral malaria from those with coma due to other causes and incidental Plasmodium falciparum parasitemia. Identifying a comatose patient with malarial retinopathy increases the likelihood of an accurate severe or cerebral malaria diagnosis. As the World Health Organization does not specify that malarial retinopathy is one of the factors included in determining a cerebral malaria diagnosis, there are significant false-positive diagnoses of cerebral malaria. Once a cerebral malaria diagnosis is assigned, other possibilities and treatments are often excluded making an incorrect diagnosis of cerebral malaria potentially fatal. However, Plasmodium falciparum may also contribute to coma in some children with retinopathy-negative cerebral malaria, as this group is still not clinically well characterized, so all children with the WHO definition of cerebral malaria should be treated for severe malaria. Nevertheless, by raising awareness about malarial retinopathy, there could be a greater potential to accurately diagnose cerebral malaria and thus achieve more positive patient outcomes in the future. This literary review aims to raise awareness of the retinopathy by defining what it is to non-experts, explaining its pathology, clarifying the techniques needed to accurately diagnose malarial retinopathy, as well as the barriers that prevent clinicians from providing a proper diagnosis in malaria-endemic regions; and finally, discuss future directions to continue the study of malarial retinopathy.

First 1,000 days: enough for mothers but not for children? Long-term outcomes of an early intervention on maternal depressed mood and child cognitive development: follow-up of a randomised controlled trial

BACKGROUND

Child cognitive development is often compromised in contexts of poverty and adversity, and these deficits tend to endure and affect the child across the life course. In the conditions of poverty and violence that characterise many low- and middle-income countries (LMIC), the capacity of parents to provide the kind of care that promotes good child development may be severely compromised, especially where caregivers suffer from depression. One avenue of early intervention focuses on the quality of the early mother-infant relationship. The aim of this study was to examine the long-term impact of an early intervention to improve the mother-infant relationship quality on child cognitive outcomes at 13 years of age. We also estimated the current costs to replicate the intervention.

METHOD

We re-recruited 333 children from an early childhood maternal-infant attachment intervention, 'Thula Sana', when the children were 13 years old, to assess whether there were impacts of the intervention on child cognitive outcomes, and maternal mood. We used the Kaufman Assessment Battery to assess the child cognitive development and the Patient Health Questionnaire (PHQ-9) and the Self-Reporting Questionnaire (SRQ-20) to assess maternal mental health.

RESULTS

Effect estimates indicated a pattern of null findings for the impact of the intervention on child cognitive development. However, the intervention had an effect on caregiver psychological distress (PHQ-9, ES = -0.17 [CI: -1.95, 0.05] and SRQ-20, ES = -0.30 [CI: -2.41, -0.19]), but not anxiety. The annual cost per mother-child pair to replicate the Thula Sana intervention in 2019 was estimated at ZAR13,365 ($780).

CONCLUSION

In a socio-economically deprived peri-urban settlement in South Africa, a home visiting intervention, delivered by community workers to mothers in pregnancy and the first six postpartum months, had no overall effect on child cognitive development at 13 years of age. However, those caregivers who were part of the original intervention showed lasting improvements in depressed mood. Despite the fact that there was no intervention effect on long-term child outcomes, the improvements in maternal mood are important.

Pathophysiology and neurologic sequelae of cerebral malaria

Cerebral malaria (CM), results from Plasmodium falciparum infection, and has a high mortality rate. CM survivors can retain life-long post CM sequelae, including seizures and neurocognitive deficits profoundly affecting their quality of life. As the Plasmodium parasite does not enter the brain, but resides inside erythrocytes and are confined to the lumen of the brain's vasculature, the neuropathogenesis leading to these neurologic sequelae is unclear and under-investigated. Interestingly, postmortem CM pathology differs in brain regions, such as the appearance of haemorragic punctae in white versus gray matter. Various host and parasite factors contribute to the risk of CM, including exposure at a young age, parasite- and host-related genetics, parasite sequestration and the extent of host inflammatory responses. Thus far, several proposed adjunctive treatments have not been successful in the treatment of CM but are highly needed. The region-specific CM neuro-pathogenesis leading to neurologic sequelae is intriguing, but not sufficiently addressed in research. More attention to this may lead to the development of effective adjunctive treatments to address CM neurologic sequelae.

Association between Malaria Infection and Early Childhood Development Mediated by Anemia in Rural Kenya

Malaria is a leading cause of morbidity and mortality among children under five years of age, with most cases occurring in Sub-Saharan Africa. Children in this age group in Africa are at greatest risk worldwide for developmental deficits. There are research gaps in quantifying the risks of mild malaria cases, understanding the pathways linking malaria infection and poor child development, and evaluating the impact of malaria on the development of children under five years. We analyzed the association between malaria infection and gross motor, communication, and personal social development in 592 children age 24 months in rural, western Kenya as part of the WASH Benefits environmental enteric dysfunction sub-study. Eighteen percent of children had malaria, 20% were at risk for gross motor delay, 21% were at risk for communication delay, and 23% were at risk for personal social delay. Having a positive malaria test was associated with increased risk for gross motor, communication, and personal social delay while adjusting for child characteristics, household demographics, study cluster, and intervention treatment arm. Mediation analyses suggested that anemia was a significant mediator in the pathway between malaria infection and risk for gross motor, communication, and personal social development delays. The proportion of the total effect of malaria on the risk of developmental delay that is mediated by anemia across the subscales was small (ranging from 9% of the effect on gross motor development to 16% of the effect on communication development mediated by anemia). Overall, malaria may be associated with short-term developmental delays during a vulnerable period of early life. Therefore, preventative malaria measures and immediate treatment are imperative for children’s optimal development, particularly in light of projections of continued high malaria transmission in Kenya and Africa.

Early and middle childhood developmental, cognitive, and psychiatric outcomes of Malawian children affected by retinopathy positive cerebral malaria

The objective is to determine the short -and long-term developmental, cognitive, and psychiatric effects of retinopathy positive cerebral malaria (CM-R) among young children in a prospective study assessing them around the onset of disease and again 2 years at preschool and again at school age. In total, 109 children were recruited from the Queen Elizabeth Central Hospital in Blantyre, Malawi, (N = 49) with CM-R and non-malaria controls  (N = 60). Children were assessed for overall motor, language, and social skills using the Malawi Developmental Assessment Tool (MDAT) at preschool age. At school age, the same children were then given the Kaufman Assessment Battery for Children, second edition (KABC-II), which assessed global cognitive performancememory, and learning; as well as the Test of Variables of Attention (TOVA), which assessed attention. The Achenbach Child Development Checklist (CBCL) was administered at both time points to assess emotional and behavioral patterns. Controls scored significantly better on all KABC-II global domains as well as on the mental processing index than their CM-R group counterparts, but showed no performance differences in the TOVA and CBCL assessments at school age, or in the MDAT and CBCL assessments at preschool age. The MDAT total score was significantly correlated with the KABC-II sequential processing, learning, and mental processing index among CM-R survivors but not among controls. Persisting neurocognitive effects of CM can be captured with the KABC-II at school age. The MDAT at preschool age is correlated with the KABC-II among CM-R survivors and can be used to capture early emerging developmental deficits due to CM-R.

Inhaled nitric oxide and cognition in pediatric severe malaria: A randomized double-blind placebo controlled trial

BACKGROUND

Severe malaria is a leading cause of acquired neurodisability in Africa and is associated with reduced nitric oxide (NO) bioavailability. A neuroprotective role for inhaled NO has been reported in animal studies, and administration of inhaled NO in preterm neonates with respiratory distress syndrome is associated with a 47% reduced risk of cognitive impairment at two years of age.

METHODS

A randomized double-blind placebo-controlled trial of inhaled NO versus placebo as an adjunctive therapy for severe malaria was conducted in Uganda between 2011 and 2013. Children received study gas for a maximum 72 hours (inhaled NO, 80 parts per million; room air placebo). Neurocognitive testing was performed on children<5 years at 6 month follow-up. The neurocognitive outcomes assessed were overall cognition (a composite of fine motor, visual reception, receptive language, and expressive language), attention, associative memory, and the global executive composite. Main outcomes were attention, associative memory, and overall cognitive ability.

RESULTS

Sixty-one children receiving iNO and 59 children receiving placebo were evaluated. Forty-two children (35.0%) were impaired in at least one neurocognitive domain. By intention-to-treat analysis, there were no differences in unadjusted or unadjusted age-adjusted z-scores for overall cognition (β (95% CI): 0.26 (-0.19, 0.72), p = 0.260), attention (0.18 (-0.14, 0.51), p = 0.267), or memory (0.14 (-0.02, 0.30), p = 0.094) between groups by linear regression. Children receiving inhaled NO had a 64% reduced relative risk of fine motor impairment than children receiving placebo (relative risk, 95% CI: 0.36, 0.14-0.96) by log binomial regression following adjustment for anticonvulsant use.

CONCLUSIONS

Severe malaria is associated with high rates of neurocognitive impairment. Treatment with inhaled NO was associated with reduced risk of fine motor impairment. These results need to be prospectively validated in a larger study powered to assess cognitive outcomes in order to evaluate whether strategies to increase bioavailable NO are neuroprotective in children with severe malaria.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01255215.

Confirmatory factor analysis of the Kaufman assessment battery in a sample of primary school-aged children in rural South Africa

The Kaufman Assessment Battery for Children, Second Edition, measures cognitive processing, includes non-verbal sub-tests, and is increasingly used in low- and middle-income countries. While the Kaufman Assessment Battery for Children, Second Edition, has been validated in the United States, a psychometric evaluation has not been conducted in Southern Africa. This study aims to establish the reliability and validity of the Kaufman Assessment Battery for Children, Second Edition, among a sample of 376 primary school-aged children in rural South Africa (7–11 years). We examined Cronbach’s alpha and conducted a confirmatory factor analysis. The battery showed good reliability (mental processing index [α = .78]), and the originally validated structure of the Kaufman Assessment Battery for Children, Second Edition, was maintained (χ2 = 16.30, p = .432). Mean scores were low on the Planning sub-scale. On the Simultaneous sub-scale, the mean score was higher for the supplementary sub-test Block Counting versus the core sub-test Triangles. With translation and the inclusion of supplementary sub-tests, the Kaufman Assessment Battery for Children, Second Edition, is an appropriate assessment to use in this context (150/150).

[Formula: see text]Selecting measures for the neurodevelopmental assessment of children in low- and middle-income countries

Diseases affecting millions of children in low- and middle-income countries (LMICs), such as malnutrition, micronutrient deficiency, malaria, and HIV, can lead to adverse neurodevelopmental outcomes. Thus, a key health outcome in children is neurodevelopmental status. In this paper, the neurodevelopmental screening and testing measures most commonly utilized in LMICs are reviewed, and a matrix is presented to help researchers and clinicians determine which measures may be most useful for various LMIC inquiries. The matrix is based on an Internet literature review of 114 publications for the period January 1998 to February 2016, reporting the psychometric properties of instruments tested in LMIC children. The measures are classified as screening tests or more detailed tests that include both comprehensive batteries of general development and tests of specific domains. For completeness, two experts have reviewed this paper, as well as the authors. An overview of the tests used to date is presented, including the benefits and drawbacks of each test, in order to provide researchers and developmental clinicians with a way to decide which tests may be best suited to their developmental assessment goals. Remarkable progress has been made in neurodevelopmental testing in children in LMICs over the past two decades but there remains a need for additional research in this area to develop new tests, better evaluate and adapt current tests, and assess test validity and reliability across cultures.

Cognitive Outcomes and Psychiatric Symptoms of Retinopathy-Positive Cerebral Malaria: Cohort Description and Baseline Results

Cerebral malaria (CM) is a common cause of death and disability among children in sub-Saharan Africa. Many prior studies of neuropsychiatric morbidity have been limited by a cross-sectional design or a short duration of follow-up. Most have included subjects who may have presented with coma due to a disease process other than CM. No studies have assessed the relationship between magnetic resonance imaging (MRI) findings and long-term outcomes. The Cognitive Outcomes and Psychiatric symptoms of retinopathy-positive CM (COPS) cohort is the first large (N = 221) prospectively recruited cohort of stringently defined cases of CM and hospital-based, age-matched, non-CM controls in whom cognitive and psychiatric outcomes are assessed with standardized measures semi-annually for up to 5 years. We report baseline characteristics of the cohort and outcomes at 1 month. At enrollment, CM cases were more likely to come from families with fewer socioeconomic resources and to have health characteristics that increase risk for malaria. In children younger than 5 years, cases were delayed in motor, language, and social development by approximately 6 months, compared with controls. More significant delays occurred in those with MRI abnormalities at the 1-month follow-up visit. There were no differences between cases and controls in inhibitory self-control, nor in cognitive function in children ≥ 5 years of age. The latter finding may be related to the smaller sample size, case-control imbalance in socioeconomic status, or the use of cognitive and behavioral assessments that are less culturally appropriate to this population. Continued follow-up will help determine predictors of long-term outcomes.

Plasmodium falciparum Histidine-Rich Protein-2 Plasma Concentrations Are Higher in Retinopathy-Negative Cerebral Malaria Than in Severe Malarial Anemia

Background

Malaria retinopathy has been proposed as marker of “true” cerebral malaria (CM), ie, coma due to Plasmodium falciparum vs coma due to other causes, with incidental P falciparum parasitemia. Plasma P falciparum histidine-rich protein-2 (PfHRP2) concentrations distinguish retinopathy-positive (RP) from retinopathy-negative (RN) CM but have not been compared between RN CM and other forms of severe malaria or asymptomatic parasitemia (AP).

Methods

We compared plasma PfHRP2 concentrations in 260 children with CM (247 examined for retinopathy), 228 children with severe malarial anemia (SMA), and 30 community children with AP.

Results

Plasmodium falciparum HRP2 concentrations were higher in children with RP CM than RN CM (P = .006), with an area under the receiver operating characteristic curve of 0.61 (95% confidence interval, 0.53–0.68). Plasmodium falciparum HRP2 concentrations and sequestered parasite biomass were higher in RN CM than SMA (both P < .03) or AP (both P < .001).

Conclusions

Plasmodium falciparum HRP2 concentrations are higher in children with RN CM than in children with SMA or AP, suggesting that P falciparum is involved in disease pathogenesis in children with CM. Plasmodium falciparum HRP2 concentrations may provide a more feasible and consistent assessment of the contribution of P falciparum to severe disease than malaria retinopathy.

Brain-derived Neurotrophic Factor Is Associated With Disease Severity and Clinical Outcome in Ugandan Children Admitted to Hospital With Severe Malaria

BACKGROUND

Malaria remains a leading cause of childhood death and neurologic disability in sub-Saharan Africa. Here, we test the hypothesis that malaria-induced alterations to circulating brain-derived neurotrophic factor (BDNF) are associated with poor clinical outcomes in children with severe malaria.

METHODS

We quantified BDNF (by enzyme-linked immunosorbent assay) in plasma samples collected [at presentation (day 1), day 3 and day 14], during a prospective study of Ugandan children admitted to hospital with severe malaria (n = 179).

RESULTS

BDNF concentration at presentation (day 1) was lower in children with cerebral malaria (P < 0.01), coma (P < 0.01), Lambaréné Organ Dysfunction Score >1 (P < 0.05) and respiratory distress (P < 0.01). Higher BDNF concentration at presentation was associated with shorter time to coma recovery [hazard ratio = 1.655 (1.194-2.293); P = 0.002] and a reduced odds ratio of disability [0.50 (0.27-0.94); P = 0.047] and death [0.45 (0.22-0.92); P = 0.035]. BDNF concentration was lower on day 1 and increased in children surviving severe malaria (day 14; P < 0.0001).

CONCLUSIONS

Our findings provide the new evidence linking circulating BDNF with disease severity, coma recovery and clinical outcome in children with severe malaria.

Exploring neurodevelopmental outcome measures used in children with cerebral malaria: the perspectives of caregivers and health workers in Malawi

BACKGROUND

Progress has been made in tackling malaria however there are still over 207 million cases worldwide, the majority in children. As survival rates improve, numbers of children with long-term neurodisabling sequelae are likely to increase. Most outcome studies in cerebral malaria (CM) have focused only on body function and structure and less on outcomes within the broader framework of the International Classification of Functioning and Disability (ICF). The aim of this study was to utilise qualitative methods to identify relevant clinical outcomes in CM to support formulation of a core outcome set relevant to CM and other acquired brain injuries for use in future clinical trials.

METHODS

In depth interviews with parent/caregivers (CGs) of children with/without previous CM (N = 19), and in depth interviews with health professionals (N = 18) involved in their care were conducted in community and clinical settings in and around Blantyre, Malawi. Interviews were audio taped, transcribed, translated and a thematic content analysis was conducted. Themes were categorised and placed firstly in an iterative framework derived from the data but then within the ICF framework.

RESULTS

Outcomes perceived as important to carers and professionals fulfilled each level of the ICF. These included impairment in body function and structure (contractures, impaired mobility, visual problems, seizures, cognitive function and feeding); activity and participation outcomes (learning, self-care, relationships in school, play and activities of daily living). Other issues emerging included the social and emotional implications of CM on the family, and balancing care of children with neurodisability with demands of daily life, financial pressures, and child protection. Themes of stigma and discrimination were described; these were perceived to negatively influence care, participation and integration of carer and child into the community.

CONCLUSIONS

Outcomes considered important for parents/caregivers and professionals working with children post CM cross all aspects of the ICF framework (impairment, functioning and participation). Outcomes emphasised by families and carers in cross-cultural settings must be given adequate attention when conducting clinical studies in these settings.

Long-term Behavioral Problems in Children With Severe Malaria

BACKGROUND

Severe malaria in children is associated with long-term neurocognitive impairment, but it is unclear whether it is associated with long-term behavioral problems.

METHODS

Children <5 years old with cerebral malaria (CM) or severe malarial anemia (SMA) treated at Mulago Hospital, Kampala, Uganda were assessed for behavioral outcomes at 0, 6, 12, and 24 months using the Child Behavior Checklist. Sample sizes at 0, 12, and 24 months were 122, 100, and 80 in the CM group, 130, 98, and 81 in the SMA group, and 149, 123, and 90 in healthy community control (CC) children, respectively. Age adjusted z-scores for behavioral outcomes were computed using scores for the CC group. Study groups were compared using regression models adjusted for age, nutritional status, preschool education, and socioeconomic status.

RESULTS

At 12 months, children with SMA had higher z-scores than CC children for internalizing (mean difference, 0.49; SE, 0.14; P = .001), externalizing (mean difference, 0.49; SE, 0.15; P = .001), and total problems (mean difference, 0.51; SE, 0.15; P < .001). Children with CM had higher adjusted z-scores than CC children for externalizing problems (mean difference, 0.39; SE, 0.15; P = .009) but not internalizing or total problems. At 24 months, children with CM or SMA both had increased internalizing and externalizing behavioral problems compared with CC children (P ≤ .05 for all).

CONCLUSIONS

CM and SMA are associated with long-term internalizing and externalizing behavioral problems in children. They may contribute substantially to mental health morbidity in children <5 years old in malaria endemic areas.

Cognition, behavior, and the ILAE Classification of the Epilepsies: A view from Africa

Recent ILAE revisions to the definition and classification of the epilepsies have highlighted cognitive-behavioral comorbidities (CBCs). Integrating a CBC dimension within a formal classification scheme would more fully account for the burden of epilepsy. This would be technically challenging, because we use fundamentally different methods to conceptualize, define, and diagnose CBCs that require additional expertise. In low resource settings such as sub-Saharan Africa (SSA), CBC burden is high. Existing classification systems are inevitably simplified in practice, because complex classifications require training and technologies that rarely exist in these settings. This makes low-resource settings a good place to develop simple methods to integrate CBCs into existing classifications so that they ultimately will communicate the full burden of epilepsy. This article is part of a Special Issue entitled "The new approach to classification: Rethinking cognition and behavior in epilepsy".

Longitudinal Visuomotor Development in a Malaria Endemic Area: Cerebral Malaria and Beyond

Paediatric cerebral malaria is the most serious complication of Plasmodium falciparum infection. While the majority recover, long-term cognitive impairment has been highlighted as a significant and neglected problem. Persistent or serious deficits in processes such as attention or behavioural inhibition should be manifest in changes to performance on oculomotor tasks. Therefore we investigated the impact of cerebral malaria on the development of reflexive pro-saccades and antisaccades. In a longitudinal study, 47 children previously admitted with retinopathy-confirmed cerebral malaria (mean age at admission 54 months), were compared with 37 local healthy controls (mean ages at first study visit 117 and 110 months respectively). In each of three or four test sessions, over a period of up to 32 months, participants completed 100 prosaccade tasks and 100 antisaccade tasks. Eye movements were recorded using infrared reflectance oculography; prosaccade, correct antisaccade and error prosaccade latency, and antisaccade directional error rate were calculated. Hierarchical linear modelling was used to investigate the effect of age and the influence of cerebral malaria on these parameters. Data were also collected from an independent, older group (mean age 183 months) of 37 local healthy participants in a separate cross-sectional study. Longitudinal data exhibited the expected decrease in latency with age for all saccade types, and a decrease in the antisaccade directional error rate. Hierarchical linear modelling confirmed that age had a statistically significant effect on all parameters (p< = 0.001). However, there were no statistically significant differences between the cerebral malaria and control groups. Combining groups, comparison with the literature demonstrated that antisaccade directional error rate for the Malawi sample was significantly higher than expected, while latencies for all saccade types were indistinguishable from published. The high directional error rate was also confirmed in the older, healthy Malawian participants from the cross sectional study. Our observation of similar oculomotor performance in cerebral malaria and control groups at long follow-up periods suggests that cerebral malaria survivors are not at a generally increased risk of persistent cognitive deficits. Our data raise questions about the prevailing hypothesis that cerebral malaria has gross impacts on the development of processes such as attention and behavioural inhibition. More importantly, our novel finding of a clear difference in antisaccade performance between all of the Malawi participants and published data suggests that the Malawian paediatric population as a whole faces serious challenges to cognitive development beyond cerebral malaria.

Malaria illness mediated by anaemia lessens cognitive development in younger Ugandan children

BACKGROUND

Asymptomatic falciparum malaria is associated with poorer cognitive performance in African schoolchildren and intermittent preventive treatment of malaria improves cognitive outcomes. However, the developmental benefits of chemoprevention in early childhood are unknown. Early child development was evaluated as a major outcome in an open-label, randomized, clinical trial of anti-malarial chemoprevention in an area of intense, year-round transmission in Uganda.

METHODS

Infants were randomized to one of four treatment arms: no chemoprevention, daily trimethoprim-sulfamethoxazole, monthly sulfadoxine-pyrimethamine, or monthly dihydroartemisinin-piperaquine (DP), to be given between enrollment (4-6 mos) and 24 months of age. Number of malaria episodes, anaemia (Hb < 10) and neurodevelopment [Mullen Scales of Early Learning (MSEL)] were assessed at 2 years (N = 469) and at 3 years of age (N = 453); at enrollment 70 % were HIV-unexposed uninfected (HUU) and 30 % were HIV-exposed uninfected (HEU).

RESULTS

DP was highly protective against malaria and anaemia, although trial arm was not associated with MSEL outcomes. Across all treatment arms, episodes of malarial illness were negatively predictive of MSEL cognitive performance both at 2 and 3 years of age (P = 0.02). This relationship was mediated by episodes of anaemia. This regression model was stronger for the HEU than for the HUU cohort. Compared to HUU, HEU was significantly poorer on MSEL receptive language development irrespective of malaria and anaemia (P = 0.01).

CONCLUSIONS

Malaria with anaemia and HIV exposure are significant risk factors for poor early childhood neurodevelopment in malaria-endemic areas in rural Africa. Because of this, comprehensive and cost/effective intervention is needed for malaria prevention in very young children in these settings.

Cerebral malaria is associated with long-term mental health disorders: a cross sectional survey of a long-term cohort

BACKGROUND

Cerebral malaria (CM) and severe malarial anaemia (SMA) are associated with neuro-developmental impairment in African children, but long-term mental health disorders in these children are not well defined.

METHODS

A cohort of children previously exposed to CM (n = 173) or SMA (n = 99) had neurologic assessments performed and screening for behaviour difficulties using the Strengths and Difficulties Questionnaire (SDQ) a median of 21 months after the disease episode. These findings were compared to concurrently recruited community children (CC, n = 108). Participants with SDQ total difficulties score ≥ 17 had a mental health interview with the child and adolescent version of the Mini-International Neuropsychiatric Interview (MINI-KID) and a sample had brain magnetic resonance imaging (MRI).

RESULTS

Fifty-five children had SDQ score ≥ 17. On the MINI-KID, these children were classified as having no difficulties (n = 18), behaviour difficulties only (n = 13) or a mental health disorder (n = 24). Behaviour difficulties were seen in similar frequencies in CM (3.5%), SMA (4.0%) and CC (2.8%). In contrast, mental health disorders were most frequent in CM (10.4%), followed by SMA (4.0%) and CC (1.8%). Externalizing disorders (conduct, oppositional defiance and attention deficit hyperactivity) were the most common mental health disorders. The median total coma duration was 72 (IQR 36.0-115.0) h in patients with mental health disorders compared to 48 (IQR 28.5-78.7) h in those without, p = 0.039. Independent risk factors for mental health disorder included neurologic deficit at discharge (OR 4.09 (95% CI 1.60, 10.5) and seizure recurrences during hospitalization, (OR 2.80, 95% CI 1.13, 6.97). Brain MRI findings consistent with small vessel ischaemic neural injury was seen in over half of these children.

CONCLUSIONS

Cerebral malaria may predispose children to mental health disorders, possibly as a consequence of ischaemic neural injury. There is urgent need for programmes of follow-up, diagnosis and interventions for these children.

Neurocognitive domains affected by cerebral malaria and severe malarial anemia in children

This study assessed the effects of cerebral malaria (CM) and severe malarial anemia (SMA) on individual neurocognitive domains. Eighty children with CM, 86 with SMA, and 61 community children (CC) were assessed for gross motor skills, fine motor skills, visual reception, receptive language, and expressive language a week after discharge (CM or SMA) or at enrolment (CC), and 6 and 12 months later. At 12-months follow-up, children with CM had significantly lower scores than CC for all outcomes. Children with SMA had significantly lower scores than CC for visual reception, receptive language, and expressive language, and scores that were lower but did not reach significance for gross and fine motor skills. Children with CM had significantly lower scores than children with SMA for fine motor skills. Children with SMA and CM have long-term impairment in multiple neurocognitive domains. Fine motor skills may be affected more profoundly in CM than SMA.

Malaria in school-age children in Africa: an increasingly important challenge

School-age children have attracted relatively little attention as a group in need of special measures to protect them against malaria. However, increasing success in lowering the level of malaria transmission in many previously highly endemic areas will result in children acquiring immunity to malaria later in life than has been the case in the past. Thus, it can be anticipated that in the coming years there will be an increase in the incidence of both uncomplicated and severe malaria in school-age children in many previously highly endemic areas. In this review, which focuses primarily on Africa, recent data on the prevalence of malaria parasitaemia and on the incidence of clinical malaria in African school-age children are presented and evidence that malaria adversely effects school performance is reviewed. Long-lasting insecticide treated bednets (LLIN) are an effective method of malaria control but several studies have shown that school-age children use LLINs less frequently than other population groups. Antimalarial drugs are being used in different ways to control malaria in school-age children including screening and treatment and intermittent preventive treatment. Some studies of chemoprevention in school-age children have shown reductions in anaemia and improved school performance but this has not been the case in all trials and more research is needed to identify the situations in which chemoprevention is likely to be most effective and, in these situations, which type of intervention should be used. In the longer term, malaria vaccines may have an important role in protecting this important section of the community from malaria. Regardless of the control approach selected, it is important this is incorporated into the overall programme of measures being undertaken to enhance the health of African school-age children.

Cerebral malaria retinopathy predictors of persisting neurocognitive outcomes in Malawian children

BACKGROUND

Neuropsychological sequelae from pediatric cerebral malaria (CM) have been well-documented. Although malaria-specific retinopathy during acute illness has become a defining criterion for CM, its relationship to neurocognitive sequelae has not been documented. This relationship is important if malaria-specific retinopathy reflects the possible brain neuropathogenesis leading to long-term neurocognitive deficits.

METHODS

From 2008 to 2012, 49 Malawian children 4.5-12 years of age surviving retinopathy-positive CM (CM-R) were tested 1-6 yrs after illness with the Kaufman Assessment Battery for Children, 2 edition, the tests of variables of attention and the Achenbach Child Behavior Checklist. In an observational study of a cohort of cerebral malaria survivors, these neurocognitive and behavioral outcomes were statistically related to types and severity of retinopathy measures, while controlling for age, sex, body mass index, socioeconomic status and time interval between illness and testing.

RESULTS

Worse scores for hemorrhages, papilledema, optic disk hyperemia, retinal whitening of macula and foveal annulus were associated with poorer Kaufman Assessment Battery for Children, 2 edition mental processing index and global scale scores. Disk hyperemia was also predictive of tests of variables of attention D prime overall attention performance (inattention) and commission errors (impulsivity). Few associations were found between retinopathy scores and Achenbach Child Behavior Checklist (emotional and behavioral) outcomes.

CONCLUSIONS

We are the first to report the relationship between severity of malaria-specific retinopathy during acute illness in CM survivors and persisting neurocognitive problems. These findings support earlier studies documenting that severity of retinopathy during acute illness is medically prognostic in CM survivors. We extend these findings to include long-term neurocognitive outcomes.

Pathogenesis of cerebral malaria--inflammation and cytoadherence

Despite decades of research on cerebral malaria (CM) there is still a paucity of knowledge about what actual causes CM and why certain people develop it. Although sequestration of P. falciparum infected red blood cells has been linked to pathology, it is still not clear if this is directly or solely responsible for this clinical syndrome. Recent data have suggested that a combination of parasite variant types, mainly defined by the variant surface antigen, P. falciparum erythrocyte membrane protein 1 (PfEMP1), its receptors, coagulation and host endothelial cell activation (or inflammation) are equally important. This makes CM a multi-factorial disease and a challenge to unravel its causes to decrease its detrimental impact.

Severe malarial anemia is associated with long-term neurocognitive impairment

BACKGROUND

Cerebral malaria (CM) is associated with long-term neurocognitive impairment in children ≥5 years of age. No prospective studies to date have assessed neurocognitive impairment in children with CM <5 years of age, or in children with severe malarial anemia (SMA), a form of severe malaria estimated to affect as many as 5 million children annually.

METHODS

Children <5 years of age presenting to Mulago Hospital, Kampala, Uganda, with CM (n = 80) or SMA (n = 86) were assessed for overall cognitive ability, attention, and associative memory 1 week after discharge and 6 and 12 months later. The z scores for each domain were computed based on scores of 61 healthy community children (CC), who were also tested at enrollment and 6 and 12 months later. Groups were compared using mixed linear models, adjusted for age, weight for age, and child's education.

RESULTS

At 12 months, children with CM had lower adjusted scores than CC in cognitive ability (P < .001), attention (P = .02), and associative memory, (P = .002). Children with SMA had lower scores than CC in cognitive ability (P = .01) but not attention or associative memory. Cognitive ability scores in children with CM and SMA did not differ significantly.

CONCLUSIONS

In children <5 years of age, SMA is associated with long-term impairment in cognitive ability, whereas CM is associated with additional impairment in the areas of attention and associative memory. SMA may be a major contributor to long-term neurocognitive impairment in children in sub-Saharan Africa.

PPARγ agonists improve survival and neurocognitive outcomes in experimental cerebral malaria and induce neuroprotective pathways in human malaria

Cerebral malaria (CM) is associated with a high mortality rate, and long-term neurocognitive impairment in approximately one third of survivors. Adjunctive therapies that modify the pathophysiological processes involved in CM may improve outcome over anti-malarial therapy alone. PPARγ agonists have been reported to have immunomodulatory effects in a variety of disease models. Here we report that adjunctive therapy with PPARγ agonists improved survival and long-term neurocognitive outcomes in the Plasmodium berghei ANKA experimental model of CM. Compared to anti-malarial therapy alone, PPARγ adjunctive therapy administered to mice at the onset of CM signs, was associated with reduced endothelial activation, and enhanced expression of the anti-oxidant enzymes SOD-1 and catalase and the neurotrophic factors brain derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the brains of infected mice. Two months following infection, mice that were treated with anti-malarials alone demonstrated cognitive dysfunction, while mice that received PPARγ adjunctive therapy were completely protected from neurocognitive impairment and from PbA-infection induced brain atrophy. In humans with P. falciparum malaria, PPARγ therapy was associated with reduced endothelial activation and with induction of neuroprotective pathways, such as BDNF. These findings provide insight into mechanisms conferring improved survival and preventing neurocognitive injury in CM, and support the evaluation of PPARγ agonists in human CM.

Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection that is associated with long-term neurocognitive impairment in about a third of survivors even when optimal anti-malarial therapy is used. Since both the parasite and the host immune response to infection play a role in the development of CM, adjunctive therapies that modulate the host response, given in conjunction with anti-parasitic therapy, may improve survival and prevent neurocognitive injury. Here we examine the effects of PPARγ agonists on neurocongitive injury using a mouse model of CM. We demonstrate that PPARγ agonists, when administered with anti-malarials, protected mice from developing brain atrophy and neurocognitive impairment. This was associated with induction of anti-oxidant and neuroprotective pathways in the brains of infected mice. We also observed the same neuroprotective pathways induced in patients with falciparum malaria that received PPARγ adjunctive therapy. Our findings suggest that PPARγ agonists may be valuable in the treatment and prevention of CM-induced neurocognitive injury, and support the testing of PPARγ agonists in patients with CM.

Contrasting pediatric and adult cerebral malaria: the role of the endothelial barrier

Malaria affects millions of people around the world and a small subset of those infected develop cerebral malaria. The clinical presentation of cerebral malaria differs between children and adults, and it has been suggested that age-related changes in the endothelial response may account for some of these differences. During cerebral malaria, parasites sequester within the brain microvasculature but do not penetrate into the brain parenchyma and yet, the infection causes severe neurological symptoms. Endothelial dysfunction is thought to play an important role in mediating these adverse clinical outcomes. During infection, the endothelium becomes activated and more permeable, which leads to increased inflammation, hemorrhages, and edema in the surrounding tissue. We hypothesize that post-natal developmental changes, occurring in both endothelial response and the neurovascular unit, account for the differences observed in the clinical presentations of cerebral malaria in children compared with adults.

Mild Plasmodium falciparum malaria following an episode of severe malaria is associated with induction of the interferon pathway in Malawian children

Infection with Plasmodium falciparum can lead to a range of severe to minimal symptoms, occasionally resulting in death in young children or nonimmune adults. In areas of high transmission, older children and adults generally suffer only mild or asymptomatic malaria infections and rarely develop severe disease. The immune features underlying this apparent immunity to severe disease remain elusive. To gain insight into host responses associated with severe and mild malaria, we conducted a longitudinal study of five children who first presented with severe malaria and, 1 month later, with mild malaria. Employing peripheral blood whole-genome profiling, we identified 68 genes that were associated with mild malaria compared to their expression in the severe malaria episode (paired Students t test, P < 0.05). These genes reflect the interferon (IFN) pathway and T cell biology and include IFN-induced protein transcripts 1 to 3, oligoadenylate synthetases 1 and 3, and the T cell markers cathepsin W and perforin. Gene set enrichment analysis identified Gene Ontology (GO) pathways associated with mild malaria to include the type I interferon-mediated signaling pathway (GO 0060337), T cell activation (GO 0042110), and other GO pathways representing many aspects of immune activation. In contrast, only six genes were associated with severe malaria, including thymidine kinase 1, which was recently found to be a biomarker of cerebral malaria susceptibility in the murine model, and carbonic anhydrase, reflecting the blood's abnormal acid base environment during severe disease. These data may provide potential insights to inform pathogenesis models and the development of therapeutics to reduce severe disease outcomes due to P. falciparum infection.

Child neurology services in Africa

The first African Child Neurology Association meeting identified key challenges that the continent faces to improve the health of children with neurology disorders. The capacity to diagnose common neurologic conditions and rare disorders is lacking. The burden of neurologic disease on the continent is not known, and this lack of knowledge limits the ability to lobby for better health care provision. Inability to practice in resource-limited settings has led to the migration of skilled professionals away from Africa. Referral systems from primary to tertiary are often unpredictable and chaotic. There is a lack of access to reliable supplies of basic neurology treatments such as antiepileptic drugs. Few countries have nationally accepted guidelines either for the management of epilepsy or status epilepticus. There is a great need to develop better training capacity across Africa in the recognition and management of neurologic conditions in children, from primary health care to the subspecialist level.

The 'hidden' burden of malaria: cognitive impairment following infection

BACKGROUND

The burden of post-malaria cognitive impairment is often overlooked. Given the large number of infections occurring worldwide, the magnitude of the problem is likely to be substantial. The objectives of this paper are; (i) to assess the evidence on post malarial cognitive impairment or impact on school education; (ii) to assess the possible positive impact of malaria drug prophylaxis on cognition; and (iii) to suggest recommendations on minimizing the burden of post-malarial cognitive impairment.

METHODS

PUBMED and SCOPUS were searched for all articles with the key word 'Malaria' in the title field and 'cognitive impairment' in any field. Google Scholar was searched for the same keywords anywhere in the article. The search was restricted to articles published in English within the last 15 years (1995-2010). After filtering of abstracts from the initial search, 44 papers had research evidence on this topic.

RESULTS & DISCUSSION

Cognitive abilities and school performance were shown to be impaired in sub-groups of patients (with either cerebral malaria or uncomplicated malaria) when compared with healthy controls. Studies comparing cognitive functions before and after treatment for acute malarial illness continued to show significantly impaired school performance and cognitive abilities even after recovery. Malaria prophylaxis was shown to improve cognitive function and school performance in clinical trials when compared to placebo groups. The implications of these findings are discussed.