Correlates of Plasma Citrulline, a Potential Marker of Enterocyte Mass, among Children with Stunting: A Cross-Sectional Study in Uganda.

BACKGROUND: Environmental enteric dysfunction (EED) is associated with stunting. Citrulline, produced in mature enterocytes, may be a valuable biomarker of small intestinal enterocyte mass in the context of EED. OBJECTIVES: We aimed to explore the correlates of plasma citrulline (p-cit) in children with stunting. METHODS: In a cross-sectional study using baseline data from the community-based MAGNUS (milk affecting growth, cognition and the gut in child stunting) trial (ISRCTN13093195), we explored potential correlates of p-cit in Ugandan children with stunting aged 12-59 mo. Using linear regression in univariate and multivariate models, we explored associations with socioeconomics, diet, micronutrient status, and water, sanitation, and hygiene characteristics. The influence of covariates age, fasting, and systemic inflammation were also explored. RESULTS: In 750 children, the mean ± standard deviation age was 32.0 ± 11.7 mo, and height-for-age z-score was -3.02 ± 0.74. P-cit, available for 730 children, differed according to time fasted and was 20.7 ± 8.9, 22.3 ± 10.6 and 24.2 ± 13.1 µmol/L if fasted <2, 2-5 and >5 h, respectively. Positive correlates of p-cit were age [0.07; 95% confidence interval (CI): 0.001, 0.15 µmol/L] and log10 serum insulin-like growth factor-1 (8.88; 95% CI: 5.09, 12.67 µmol/L). With adjustment for systemic inflammation, the association with serum insulin-like growth factor-1 reduced (4.98; 95% CI: 0.94, 9.03 µmol/L). Negative correlates of p-cit included food insecurity, wet season (-3.12; 95% CI: -4.97, -1.26 µmol/L), serum C-reactive protein (-0.15; 95% CI: -0.20, -0.10 µmol/L), serum α1-acid glycoprotein (-5.34; 95% CI: -6.98, -3.70 µmol/L) and anemia (-1.95; 95% CI: -3.72, -0.18 µmol/L). Among the negatively correlated water, sanitation, and hygiene characteristics was lack of soap for handwashing (-2.53; 95% CI: -4.82, -0.25 µmol/L). Many associations attenuated with adjustment for inflammation. CONCLUSIONS: Many of the correlates of p-cit are characteristic of populations with a high EED prevalence. Systemic inflammation is strongly associated with p-cit and is implicated in EED and stunting. Adjustment for systemic inflammation attenuates many associations, reflecting either confounding, mediation, or both. This study highlights the complex interplay between p-cit and systemic inflammation.

Correlates of body composition in children with stunting: A cross-sectional study in Uganda.

BACKGROUND: Development of body composition (BC) may be disrupted in children with stunting. Such disruption may affect later risk of excess adiposity and metabolic health, yet few studies have investigated correlates of BC in children with stunting. OBJECTIVE: We aimed to investigate nutritional status, infection and inflammation, breastfeeding behaviors and other factors as correlates of BC in children with stunting. METHODS: Among Ugandan children with a height-for-age z-score <-2, BC was estimated using bioelectrical impedance analysis and compared to UK references. We used multiple linear regression analysis to identify correlates of fat mass (FM), fat-free mass (FFM), FM-index (FMI), and FFM-index (FFMI) and height, adjusting for sex and age. RESULTS: In 750 children aged 1-5 years, FMI was 0.46 [95%CI:0.38,0.54] and FFMI 0.18 [95%CI:0.11,0.26] z-scores lower than UK references. Elevated serum α1-acid glycoprotein was associated with 1.14 [0.76,1.52] cm lower height, 0.50 [0.35,0.65] kg/m2 less FFMI, and 0.48 [0.31, 0.66] kg/m2 greater FMI. Similar, weaker, associations for elevated serum C-reactive protein were detected. A positive malaria rapid test was associated with 0.64 [0.25,1.02] cm shorter height, but 0.36 [0.18,0.54] kg/m2 greater FMI. Anemia (according to hemoglobin) was associated with 0.20 [0.07,0.33] kg less FFM in proportion with shorter height. Longer breastfeeding duration was associated with 0.03 [0.02, 0.04] kg greater FFM per month, in proportion to greater height. CONCLUSION: These children exhibited deficits in FM and FFM, proportionally to their stunted height, compared to UK references. Systemic inflammation correlated inversely with linear growth and fat-free but positively with fatness, making it a possible target for intervention where fat-free tissue accretion is desirable. Longer breastfeeding may offer protection to lean linear growth but findings for micronutrients were less clear. Longitudinal studies are warranted to support these findings. The study was registered at www.isrctn.com (Ref. ISRCTN13093195).

Correlates of early child development among children with stunting: A cross-sectional study in Uganda.

Many children in low- and middle-income countries are not attaining their developmental potential. Stunting is associated with poor child development, but it is not known which correlates of stunting are impairing child development. We explored potential socioeconomic, nutritional, clinical, and household correlates of early child development among 12-59-month-old children with stunting in a cross-sectional study in Uganda. Development was assessed using the Malawi Development Assessment Tool (MDAT) across four domains of gross and fine motor, language, and social skills. Linear regression analysis was used to assess correlates of development in the four domains and total MDAT score. Of 750 children included, the median [interquartile range] age was 30 [23-41] months, 55% of the children resided in rural settings with 21% from female-headed households and 47% of mothers had no schooling. The mean ± standard deviation height-for-age z-score (HAZ) was -3.02 ± 0.74, 40% of the children had a positive malaria test and 65% were anaemic (haemoglobin < 110 g/L). One-third had children's books at home, majority (96%) used household objects to play with and most of them (70%) used toys as pretence items like those to mimic cooking. After age, sex, and site adjustments, HAZ (0.24, 95% confidence interval [CI]: 0.14-0.33) and head circumference (0.07, 95% CI: 0.02-0.12) were positive correlates of total MDAT score, whereas weight-for-height z-score (WHZ) was not. Current breastfeeding was associated with 0.41 (95% CI: 0.17-0.65) lower total MDAT score. Children from households with a single income earner had 0.22 (95% CI: 0.06-0.37) lower total MDAT score. Furthermore, severe food insecurity, inflammation and positive malaria test were associated with lower scores for motor development. All family care indicator subscales (FCIs) positively correlated with the total MDAT score and this association was independent of household's socioeconomic status. In conclusion, stunting degree, head circumference, number of household income earners and stimulation by improved FCIs correlate with early child development among stunted children. The negative association with prolonged breastfeeding is likely due to reverse causality. Identified correlates may inform initiatives to support children with stunting attain their development potential.

Predictors of change in early child development among children with stunting: Secondary analysis of a randomized trial in Uganda.

Millions of children under 5 years in low- and middle-income countries fail to attain their development potential with accruing short- and long-term consequences. Low length/height for age (stunting) is known to be a key factor, but there is little data on how child characteristics are linked with developmental changes among children with stunting. We assessed the socioeconomic, household, anthropometric, and clinical predictors of change in early child development (ECD) among 1-5-year-old children with stunting. This was a prospective cohort study nested in a randomized trial testing effects of lipid-based nutrient supplementation among children with stunting in Uganda. Development was assessed using the Malawi Development Assessment Tool (MDAT). Multiple linear regression analysis was used to assess for predictors of change. We included 750 children with mean ±SD age of 30.2 ±11.7 months 45% of whom were female. After 12 weeks, total MDAT z-score increased by 0.40 (95%CI: 0.32; 0.48). Moderate vs severe stunting, higher fat-free mass, negative malaria test and no inflammation (serum α-1-acid glycoprotein <1 g/l) at baseline predicted greater increase in ECD scores. Older age and fat mass gain predicted a lesser increase in ECD. Our findings reinforce the link between stunting and development with more severely stunted children having a lesser increase in ECD scores over time. Younger age, freedom from malaria and inflammation, and higher fat-free mass at baseline, as well as less gain of fat mass during follow-up predicted a higher increase in developmental scores in this study. Thus, supporting fat-free mass accretion, focusing on younger children, and infection prevention may improve development among children with stunting.

Effect of lipid-based nutrient supplements on micronutrient status and hemoglobin among children with stunting: secondary analysis of a randomized controlled trial in Uganda.

BACKGROUND: Micronutrient deficiencies and anemia are widespread among children with stunting. OBJECTIVES: We assessed the effects of lipid-based nutrient supplements (LNS) containing milk protein (MP) and/or whey permeate (WP) on micronutrient status and hemoglobin (Hb) among children with stunting. METHODS: This was a secondary analysis of a randomized controlled trial. Children aged 12-59 mo with stunting were randomly assigned to LNS (100 g/d) with milk or soy protein and WP or maltodextrin for 12 wk, or no supplement. Hb, serum ferritin (S-FE), serum soluble transferrin receptor (S-TfR), plasma cobalamin (P-Cob), plasma methylmalonic acid (P-MMA), plasma folate (P-Fol), and serum retinol-binding protein (S-RBP) were measured at inclusion and at 12 wk. Data were analyzed using linear and logistic mixed-effects models. RESULTS: Among 750 children, with mean age ± SD of 32 ± 11.7 mo, 45% (n = 338) were female and 98% (n = 736) completed follow-up. LNS, compared with no supplementation, resulted in 43% [95% confidence interval (CI): 28, 60] greater increase in S-FE corrected for inflammation (S-FEci), 2.4 (95% CI: 1.2, 3.5) mg/L greater decline in S-TfR, 138 (95% CI: 111, 164) pmol/L greater increase in P-Cob, 33% (95% CI: 27, 39) reduction in P-MMA, and 8.5 (95% CI: 6.6, 10.3) nmol/L greater increase in P-Fol. There was no effect of LNS on S-RBP. Lactation modified the effect of LNS on markers of cobalamin status, reflecting improved status among nonbreastfed and no effects among breastfed children. LNS increased Hb by 3.8 (95% CI: 1.7, 6.0) g/L and reduced the odds of anemia by 55% (odds ratio: 0.45, 95% CI: 0.29, 0.70). MP compared with soy protein increased S-FEci by 14% (95% CI: 3, 26). CONCLUSIONS: LNS supplementation increases Hb and improves iron, cobalamin, and folate status, but not vitamin A status among children with stunting. LNS should be considered for children with stunting. This trial was registered at ISRCTN as 13093195.