Sickle cell trait (HbAS) and stunting in children below two years of age in an area of high malaria transmission

<p>Abstract</p> <p>Background</p> <p>While the protective effects of sickle cell trait (HbAS) against severe malaria and the resulting survival advantage are well known, the impact on the physical development in young children remains unclear. This study was aimed to investigate the relationship between HbS carriage and stunting in children below two years of age in a cohort from the Ashanti Region, Ghana.</p> <p>Methods</p> <p>1,070 children were recruited at three months of age and followed-up for 21 months with anthropometric measurements performed every three months. Incidence rate ratios with 95% confidence intervals were calculated by Poisson regression to estimate the association of β-globin genotypes with the number of malaria episodes. Odds ratios (OR) were calculated for the association between the occurrence of β-globin genotypes and/or malaria episodes and stunting. The age-dependent between-group and within-group effects for the β-globin genotypes were assessed by population-averaged models estimated by generalized estimation equation with autoregressive correlation structure.</p> <p>Results</p> <p>Analyses showed a significantly lower age-dependent risk of stunting (OR 0.56; 95% CI 0.33–0.96) in carriers of the HbAS genotype (n = 102) in comparison to those with HbAA (n = 692). This effect was restricted to children who experienced malaria episodes during the observation period suggesting that the beneficial effect of the β-globin HbS variant on the incidence of stunting is closely linked to its protection from mild malaria episodes.</p> <p>Conclusion</p> <p>The lower risk of chronic malnutrition in early childhood, mediated by protection against mild malaria episodes, may contribute to the survival advantage of HbAS carriers in areas of high malaria transmission.</p

Association between anthropometric indices and cardiometabolic risk factors in pre-school children

ABSTRACT: The world health organization (WHO) and the Identification and prevention of dietary- and lifestyle-induced health effects in children and infants- study (IDEFICS), released anthropometric reference values obtained from normal body weight children. This study examined the relationship between WHO [body mass index (BMI) and triceps- and subscapular-skinfolds], and IDEFICS (waist circumference, waist to height ratio and fat mass index) anthropometric indices with cardiometabolic risk factors in pre-school children ranging from normal body weight to obesity. Methods: A cross-sectional study with 232 children (aged 4.1 ± 0.05 years) was performed. Anthropometric measurements were collected and BMI, waist circumference, waist to height ratio, triceps- and subscapular-skinfolds sum and fat mass index were calculated. Fasting glucose, fasting insulin, homeostasis model analysis insulin resistance (HOMA-IR), blood lipids and apolipoprotein (Apo) B-100 (Apo B) and Apo A-I were determined. Pearson’s correlation coefficient, multiple regression analysis and the receiver-operating characteristic (ROC) curve analysis were run. Results: 51 % (n = 73) of the boys and 52 % (n = 47) of the girls were of normal body weight, 49 % (n = 69) of the boys and 48 % (n = 43) of the girls were overweight or obese. Anthropometric indices correlated (p 0.68 to AUC < 0.76). Conclusions: WHO and IDEFICS anthropometric indices correlated similarly with fasting insulin and HOMA-IR. The diagnostic accuracy of the anthropometric indices as a proxy to identify children with insulin resistance was similar. These data do not support the use of waist circumference, waist to height ratio, triceps- and subscapular- skinfolds sum or fat mass index, instead of the BMI as a proxy to identify pre-school children with insulin resistance, the most frequent alteration found in children ranging from normal body weight to obesity

A Prospective Nested Case-Control Study of Dengue in Infants: Rethinking and Refining the Antibody-Dependent Enhancement Dengue Hemorrhagic Fever Model

Analyses of a prospective case-control study of infant dengue by Daniel Libraty and colleagues casts doubt on the antibody-dependent enhancement model for dengue hemorrhagic fever