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.

Lead Exposure in Infancy and Subsequent Growth in Beninese Children.

Studies suggest that elevated postnatal blood lead levels (BLLs) are negatively associated with child growth. This study aimed to investigate the associations of childhood BLLs at age one year and growth outcomes at age six years (n = 661) in a cohort of children in Allada, Benin. The growth outcomes studied are weight-for-age Z-score (WAZ), height-for-age Z-score (HAZ), BMI-for-age Z-score (BMIZ), weight-for-height Z-score (WHZ), head circumference (HC), growth velocities, underweight, stunting, and wasting. Multivariable regression models examined the associations between BLLs and growth outcomes, with adjustment for potential confounders. The geometric mean BLLs was 59.3 µg/L and 82% of children had BLLs >35 µg/L at the age of 12.8 months. After adjusting for confounding factors, no overall association was found between BLL quartiles and HAZ, WAZ, BMIZ, WHZ, growth velocities, wasting, and underweight. However, boys in the highest quartile had a 1.02 cm lower HC (95% CI: [−1.81, −0.24]) as compared to the lowest quartile. Furthermore, an increased odds of being stunted was observed in children in the highest quartile of exposure compared to the first (OR: 2.43; 95% CI: [1.11−5.33]) which remained statistically significant only among girls in sex-specific strata. Blood lead was found to be associated with an increased risk of childhood stunting and a lower head circumference in a resource-limited setting.

The Impact of Maternal Depression and Parent-Child Interactions on Risk of Parasitic Infections in Early Childhood: A Prospective Cohort in Benin.

OBJECTIVES: Maternal depression occurs in 13-20% of women from low-income countries, which is associated with negative child health outcomes, including diarrheal disease. However, few studies have investigated its impact on child risk of infectious disease. We studied the impacts of maternal depressive symptoms and parent-child interactions, independently, on the risk of Plasmodium falciparum malaria and soil-transmitted helminth infection in Beninese children. METHODS: Our population included mothers and children enrolled in a clinical trial during pregnancy (MiPPAD) in Benin. The Edinburgh Postnatal Depression Scale (EPDS) assessed maternal depressive symptoms and the home observation measurement of the environment (HOME) assessed parent-child interactions. Blood and stool sample analyses diagnosed child malaria and helminth infection at 12, 18, and 24 months. Negative binomial and Poisson regression models with robust variance tested associations. RESULTS: Of the 302 mother-child pairs, 39 (12.9%) mothers had depressive symptoms. Median number of malaria episodes per child was 3 (0-14) and 29.1% children had at least one helminth infection. Higher EPDS scores were associated with lower HOME scores; relative risk (RR) 0.97 (95% confidence interval (CI) 0.95, 0.99), particularly with lower acceptance, involvement, and variety subscales; RR 0.92 (95% CI 0.85, 0.99), RR 0.82 (95% CI 0.77, 0.88), RR 0.93 (95% CI 0.88, 0.99), respectively. However, neither exposure was associated with risk of parasitic infection in children. CONCLUSIONS FOR PRACTICE: Maternal depressive symptoms are associated with poor parent-child interactions, particularly acceptance of behavior, involvement with children, and variety of interactions, but these exposures do not independently impact risk of parasitic infection in children.

The Effects of Malaria in Pregnancy on Neurocognitive Development in Children at 1 and 6 Years of Age in Benin: A Prospective Mother-Child Cohort.

BACKGROUND: Malaria in pregnancy (MiP) contributes significantly to infant mortality rates in sub-Saharan Africa and has consequences on survivors, such as preterm birth and low birth weight. However, its impact on long-term neurocognitive development in children remains unknown. METHODS: Our prospective cohort included pregnant women and their live-born singletons from the Malaria in Pregnancy Preventive Alternative Drugs clinical trial. MiP was assessed using microscopy and real-time quantitative polymerase chain reaction (qPCR). Neurocognitive development in children was assessed using the Mullen Scales of Early Learning and the Kaufman Assessment Battery for Children, 2nd edition (KABC-II), at 1 and 6 years of age, respectively. RESULTS: Of 493 pregnant women, 196 (40%) were infected with malaria at least once: 121 (31%) with placental malaria diagnosed by qPCR. Multiple linear regression B-coefficients showed that impaired gross motor scores were associated with MiP at least once (-2.55; confidence interval [95% CI]: -5.15, 0.05), placental malaria by qPCR (-4.95; 95% CI: -7.65, -2.24), and high parasite density at delivery (-1.92; 95% CI: -3.86, 0.02) after adjustment. Malaria and high parasite density at the second antenatal care visit were associated with lower KABC-II Non-Verbal Index scores at 6 years (-2.57 [95% CI: -4.86, -0.28] and -1.91 [-3.51, -0.32]), respectively. CONCLUSIONS: This prospective cohort study provides evidence that MiP, particularly late term, could have important negative consequences on child development at 1 and 6 years of age. Mechanisms behind this association must be further investigated and diagnostic methods in low-income countries should be strengthened to provide adequate treatment. CLINICAL TRIALS REGISTRATION: NCT00811421.

[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.

Follow-Up of Elevated Blood Lead Levels and Sources in a Cohort of Children in Benin.

Lead exposure is associated with poor cognitive development in children. Very few studies in sub-Saharan Africa (SSA) have studied blood lead levels (BLLs) and non-gasoline sources of exposure in children. Data from a birth cohort in Benin (2011-2013) suggested that 58% of 1-year-old children had BLLs > 50 ug/L. We aimed to investigate the prevalence of elevated BLLs (>50 µg/L and >100 µg /L) among 425 of these children at 6 years of age in 2016-2018 and to compare BLLs between age 1 and 6 years, and study sources of lead at age 6 years. BLLs were analysed by inductively coupled plasma mass spectrometry. Multiple linear regression and quantile regressions were used to study potential sources of lead. The prevalence of BLLs > 50 µg/L in children was 59.5% (Geometric Mean (GM) 56.4 µg/L, 95% CI: 54.1-58.7) at 6 years of age compared to 54.8% (GM 56.5 µg/L, 95% CI: 53.4-59.6) at 1 year of age. The prevalence of children with BLLs > 100 µg/L decreased from 14.4% at 1 year of age to 8.2% at 6 years of age. After adjustment for all other covariates, consumption of peanuts more than once per month was significantly associated with a 22.0% (95% CI: 4.6, 42.5) increment in BLLs at age 6 years compared with no consumption. Consumption of bushmeat killed by lead bullets at age 6 years was associated with an increase in the higher percentiles of BLLs (P75) compared with the absence of this source. Other potential sources of lead associated with BLLs with marginal significance were consumption of rice, paternal occupational exposure, and the presence of activity with the potential use of lead. This prospective cohort confirms the persistently high prevalence of elevated BLLs in children residing in a rural region in the south of Benin, as well as the presence of multiple and continuous sources of lead. These results highlight the need for prevention programs to reduce and eliminate lead exposure in children.

Comparison of growth models to describe growth from birth to 6 years in a Beninese cohort of children with repeated measurements.

OBJECTIVE: To select a growth model that best describes individual growth trajectories of children and to present some growth characteristics of this population. SETTINGS: Participants were selected from a prospective cohort conducted in three health centres (Allada, Sekou and Attogon) in a semirural region of Benin, sub-Saharan Africa. PARTICIPANTS: Children aged 0 to 6 years were recruited in a cohort study with at least two valid height and weight measurements included (n=961). PRIMARY AND SECONDARY OUTCOME MEASURES: This study compared the goodness-of-fit of three structural growth models (Jenss-Bayley, Reed and a newly adapted version of the Gompertz growth model) on longitudinal weight and height growth data of boys and girls. The goodness-of-fit of the models was assessed using residual distribution over age and compared with the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The best-fitting model allowed estimating mean weight and height growth trajectories, individual growth and growth velocities. Underweight, stunting and wasting were also estimated at age 6 years. RESULTS: The three models were able to fit well both weight and height data. The Jenss-Bayley model presented the best fit for weight and height, both in boys and girls. Mean height growth trajectories were identical in shape and direction for boys and girls while the mean weight growth curve of girls fell slightly below the curve of boys after neonatal life. Finally, 35%, 27.7% and 8% of boys; and 34%, 38.4% and 4% of girls were estimated to be underweight, wasted and stunted at age 6 years, respectively. CONCLUSION: The growth parameters of the best-fitting Jenss-Bayley model can be used to describe growth trajectories and study their determinants.

Neurocognitive testing in West African children 3-6 years of age: Challenges and implications for data analyses.

OBJECTIVE: When testing African children with developmental and cognitive standardized tests from high-income countries (HIC), investigators are uncertain as to whether to apply the HIC norms for these tests when standardizing a child's raw-score performance on the basis of age. The present study compared the construct validity of both raw and HIC-based standardized scores for the Mullen Scales of Early Learning (MSEL) and the Kaufman Assessment Battery in Children - 2nd edition (KABC-II) for Beninese children in a rural setting from three to six years of age. METHODS: Seventy-four children 3-4 yrs of age were assessed with the MSEL, and 61 eligible older children (5-6 yrs of age) were assessed with the KABC-II. Assessors spoke the instructions to the children and caregivers for the assessment items in the local language. The developmental quality of the home environment was evaluated with the Caldwell Home Observation for Measurement of the Environment (HOME) inventory, and a material possessions and housing quality checklist was used as a measure of socio-economic status (SES). Children's mothers were given the Raven's Progressive Matrices test (nonverbal cognitive ability), and the Edinburgh Postpartum Depression Scale (EPDS) (emotional wellbeing). RESULTS: For the MSEL, the 4-yr old group performed significantly better than the 3-yr old group on both the raw and standardized score comparisons for all scales. These differences were attenuated when using standardized scores, although the MSEL standardized cognitive composite score was still highly significant between years of age. When comparing 5- to 6-yr olds on KABC-II subtest and global scale performance, comparisons between the raw and standardized mean score performances were much less consistent. Generally, 6-yr olds performed significantly better than 5-yr olds on the raw score comparisons on the KABC-II subtests, but not so for standardized scores. Parent-child interactions assessed through the HOME measure was associated with both raw and standardized MSEL cognitive composite score outcomes on a multiple regression analysis. SES was the only significant predictor for KABC-II raw and standardized outcomes. CONCLUSION: Standardization using HIC norms was not optimal, resulting in minimal impact to account for age when using the MSEL, and lower scores for oldest children compared with youngest children when using the KABC2. This is likely due to children in Benin drifting away from HIC-based norms with each passing year of age, systematically lowering standardized performance measures. These findings support the importance of having a local comparison group of reference or control children to allow for adjusted (for age, HOME, and SES) raw score comparisons when using western-based tests for developmental and neuropsychological evaluation.

Hunting, Sale, and Consumption of Bushmeat Killed by Lead-Based Ammunition in Benin.

Human consumption of animal meat killed by lead ammunition has been reported as a risk factor for elevated blood lead levels. However, little is known about how meat killed by lead ammunition is hunted, prepared, sold, and consumed. We explored the process from hunting to consumption within communities in Benin from the perspective of preventive measures. We conducted 38 semi-structured interviews with hunters (n = 9) and sellers (n = 8) of bushmeat and families (n = 21) as consumers of bushmeat killed by lead ammunition. Data were transcribed, translated, and coded for analysis. We conducted content analysis to identify and describe key themes and processes from hunting to consumption. Many hunters (n = 7/9) used lead-based ammunition. After the meat is hunted, market sellers often buy it directly from the hunters. Amongst the hunters and sellers, few (n = 4/17) acknowledged removing the meat impacted by lead shot prior to sale. Many families (n = 15/21) mentioned consumption of the hunted bushmeat. The meat is cooked before sharing with children. Many families (n = 19/21) mentioned they look for the remains of the lead shot or remove the meat impacted by the shot. The finding suggests that hunting, sale, and consumption of bushmeat killed by lead ammunition are well-known practices in Allada, Benin. The bushmeat often hunted illegally with lead shot is sold in the markets and eventually consumed by families who attempt to clean the meat impacted by the lead shot before cooking it.

Consequences of prenatal geophagy for maternal prenatal health, risk of childhood geophagy and child psychomotor development.

OBJECTIVE: To investigate the relationship between prenatal geophagy, maternal prenatal haematological indices, malaria, helminth infections and cognitive and motor development among offspring. METHODS: At least a year after delivery, 552 of 863 HIV-negative mothers with singleton births who completed a clinical trial comparing the efficacy of sulfadoxine-pyrimethamine and mefloquine during pregnancy in Allada, Benin, responded to a nutrition questionnaire including their geophagous habits during pregnancy. During the clinical trial, helminth infection, malaria, haemoglobin and ferritin concentrations were assessed at 1st and 2nd antenatal care visits (ANV) and at delivery. After the first ANV, women were administered daily iron and folic acid supplements until three what? post-delivery. Singleton children were assessed for cognitive function at age 1 year using the Mullen Scales of Early Learning. RESULTS: The prevalence of geophagy during pregnancy was 31.9%. Pregnant women reporting geophagy were more likely to be anaemic (AOR = 1.9, 95% CI [1.1, 3.4]) at their first ANV if they reported geophagy at the first trimester. Overall, prenatal geophagy was not associated with maternal haematological indices, malaria or helminth infections, but geophagy during the third trimester and throughout pregnancy was associated with poor motor function (AOR = -3.8, 95% CI [-6.9, -0.6]) and increased odds of geophagous behaviour in early childhood, respectively. CONCLUSIONS: Prenatal geophagy is not associated with haematological indices in the presence of micronutrient supplementation. However, it may be associated with poor child motor function and infant geophagy. Geophagy should be screened early in pregnancy.

Prenatal Iron Deficiency, Neonatal Ferritin, and Infant Cognitive Function.

OBJECTIVE: To investigate the impact of prenatal maternal iron deficiency (ID) on cord blood serum ferritin (CBSF) concentration and infant cognitive and motor development. METHODS: Our prospective cohort study included 636 mother-singleton child pairs from 828 eligible pregnant women who were enrolled during their first antenatal care (ANC) visit in Allada, Benin, into a clinical trial comparing the efficacy of mefloquine and sulfadoxine-pyrimethamine. Venous blood samples of women were assessed for ferritin and hemoglobin concentrations at the first and second ANC visits (occurring at least 1-month apart) and at delivery. Women were prescribed daily iron and folic acid supplements throughout pregnancy. Hematologic examinations were repeated for cord blood at birth. At age 1 year, cognitive and motor functions of children were assessed by using the Mullen Scales of Early Learning. RESULTS: The prevalence of prenatal ID at first and second ANC visits, and at delivery was 30.5%, 34.0%, and 28.4%, respectively. CBSF concentrations were similar between ID and non-ID pregnant women. Neither prenatal ID nor CBSF concentration was associated with poor cognitive or gross motor function of children at age 1 year. CBSF concentrations were lower among mothers who had ID anemia (IDA) at delivery compared with non-IDA pregnant women (adjusted mean difference: -0.2 [95% confidence interval: -0.4 to -0.0]). CONCLUSIONS: In a malaria-endemic region, ID in pregnancy in the context of iron supplementation is neither associated with CBSF concentration nor with infant cognitive and motor development. Prenatal IDA around the time of delivery is associated with lower CBSF concentrations.

Usefulness of child development assessments for low-resource settings in francophone Africa.

OBJECTIVE: Few tools are available to screen or assess infant's cognitive development, especially in French-speaking Africa. This study evaluated the use of the French translation of the Mullen Scales of Early Learning (MSEL), and the "Ten Questions" questionnaire (TQ) in 1-year-old children in Benin, a francophone country. METHODS: A cross-sectional study was conducted in 3 health centers serving a semirural area in Benin. Three hundred fifty-seven children aged 12 months and their mothers were enrolled in 2011. Infant development was assessed at local health centers followed by a home visit to collect information on socioeconomic status, maternal Raven score, maternal depressive symptoms, and mother-child interactions (Home Observation for the Measurement of the Environment [HOME] Inventory), and to administer the TQ. RESULTS: The infant's gender (female), the HOME, and maternal education were associated with a higher Early Learning Composite score in multivariate analyses (p = .02, p = .004, p = .007, respectively). The HOME and family wealth were also associated with the Gross Motor Scale (p = .03 and p = .03, respectively). Mothers were more likely to report difficulties on the TQ when the child presented lower score on the MSEL. When considering the Gross Motor Scale as the gold standard to define moderate delays, the 2 combined motor-related questions on the TQ showed good sensitivity and specificity (76.5 and 75.7). CONCLUSION: In a low-resource rural setting in Africa, the TQ effectively identified 3 quarters of 1-year-old infants with delayed development. After this screening, the MSEL may be useful for further assessment as it showed good feasibility and sensitivity to known risk factors for poor child development.