Effects of food supplementation on cognitive function, cerebral blood flow, and nutritional status in young children at risk of undernutrition: randomized controlled trial.

OBJECTIVE: To assess the effects of food supplementation on improving working memory and additional measures including cerebral blood flow in children at risk of undernutrition. DESIGN: Randomized controlled trial. SETTING: 10 villages in Guinea-Bissau. PARTICIPANTS: 1059 children aged 15 months to 7 years; children younger than 4 were the primary population. INTERVENTIONS: Supervised isocaloric servings (≈1300 kJ, five mornings each week, 23 weeks) of a new food supplement (NEWSUP, high in plant polyphenols and omega 3 fatty acids, within a wide variety and high fortification of micronutrients, and a high protein content), or a fortified blended food (FBF) used in nutrition programs, or a control meal (traditional rice breakfast). MAIN OUTCOME MEASUREMENTS: The primary outcome was working memory, a core executive function predicting long term academic achievement. Additional outcomes were hemoglobin concentration, growth, body composition, and index of cerebral blood flow (CBFi). In addition to an intention-to-treat analysis, a predefined per protocol analysis was conducted in children who consumed at least 75% of the supplement (820/925, 89%). The primary outcome was assessed by a multivariable Poisson model; other outcomes were assessed by multivariable linear mixed models. RESULTS: Among children younger than 4, randomization to NEWSUP increased working memory compared with the control meal (rate ratio 1.20, 95% confidence interval 1.02 to 1.41, P=0.03), with a larger effect in the per protocol population (1.25, 1.06 to 1.47, P=0.009). NEWSUP also increased hemoglobin concentration among children with anemia (adjusted mean difference 0.65 g/dL, 95% confidence interval 0.23 to 1.07, P=0.003) compared with the control meal, decreased body mass index z score gain (-0.23, -0.43 to -0.02, P=0.03), and increased lean tissue accretion (2.98 cm2, 0.04 to 5.92, P=0.046) with less fat (-5.82 cm2, -11.28 to -0.36, P=0.04) compared with FBF. Additionally, NEWSUP increased CBFi compared with the control meal and FBF in both age groups combined (1.14 mm2/s×10-8, 0.10 to 2.23, P=0.04 for both comparisons). Among children aged 4 and older, NEWSUP had no significant effect on working memory or anemia, but increased lean tissue compared with FBF (4.31 cm2, 0.34 to 8.28, P=0.03). CONCLUSIONS: Childhood undernutrition is associated with long term impairment in cognition. Contrary to current understanding, supplementary feeding for 23 weeks could improve executive function, brain health, and nutritional status in vulnerable young children living in low income countries. Further research is needed to optimize nutritional prescriptions for regenerative improvements in cognitive function, and to test effectiveness in other vulnerable groups. TRIAL REGISTRATION: ClinicalTrials.gov NCT03017209.

Associations Between Vitamin D Intake and Progression to Incident Advanced Age-Related Macular Degeneration.

Purpose: There is growing evidence of the importance of nutrition in age-related macular degeneration (AMD), but no prospective studies have explored the impact of vitamin D. We evaluated the association between vitamin D intake and progression to advanced AMD. Methods: Among 2146 participants (3965 eyes), 541 (777 eyes) progressed from early or intermediate AMD to advanced disease (mean follow-up: 9.4 years) based on ocular imaging. Nutrients were log transformed and calorie adjusted. Survival analysis was used to assess associations between incident advanced disease and vitamin D intake. Neovascular disease (NV) and geographic atrophy (GA) were evaluated separately. Combined effects of dietary vitamin D and calcium were assessed based on high or low consumption of each nutrient. Results: There was a lower risk of progression to advanced AMD in the highest versus lowest quintile of dietary vitamin D intake after adjustment for demographic, behavioral, ocular, and nutritional factors (hazard ratio [HR]: 0.60; 95% confidence interval [CI]: 0.43-0.83; P trend = 0.0007). Similar results were observed for NV (HR: 0.59; 95% CI: 0.39-0.89; P trend = 0.005) but not GA (HR: 0.83; 95% CI: 0.53-1.30; P trend = 0.35). A protective effect was observed for advanced AMD among participants with high vitamin D and low calcium compared to the group with low levels for each nutrient (HR: 0.67; 95% CI: 0.50-0.88; P = 0.005). When supplement use was considered, the effect was in the protective direction but was not significant. Conclusions: A diet rich in vitamin D may prevent or delay progression to advanced AMD, especially NV. Additional exploration is needed to elucidate the potential protective role of vitamin D and its contribution to reducing visual loss.

Response to AREDS supplements according to genetic factors: survival analysis approach using the eye as the unit of analysis.

BACKGROUND/AIMS: The Age-Related Eye Disease Study (AREDS) reported the beneficial impact of antioxidant and zinc supplements on the risk of progression to advanced stages of age-related macular degeneration (AMD). We evaluated the role of genetic variants in modifying the relationship between supplementation and progression to advanced AMD. METHODS: Among 4124 eyes (2317 subjects with a genetic specimen), 882 progressed from no AMD, early or intermediate AMD to overall advanced disease, including geographic atrophy (GA) and neovascular disease (NV) over the course of the clinical trial. Survival analysis using individual eyes as the unit of analysis was used to assess the effect of supplementation on AMD outcomes, with adjustment for demographic, environmental, ocular and genetic covariates. Interaction effects between supplement groups and individual complement factor H (CFH) Y402H and age-related maculopathy susceptibility 2 (ARMS2) genotypes, and composite genetic risk groups combining the number of risk alleles for both loci, were evaluated for their association with progression. RESULTS: Among antioxidant and zinc supplement users compared with the placebo group, subjects with a non-risk genotype for CFH (TT) had a lower risk of progression to advanced AMD (HR: 0.55, 95% CI 0.32 to 0.95, p=0.033). No significant treatment effect was apparent among subjects who were homozygous for the CFH risk allele (CC). A protective effect was observed among high-risk ARMS2 (TT) carriers (HR: 0.52, 95% CI 0.33 to 0.82, p=0.005). Similar results were seen for the NV subtype but not GA. CONCLUSIONS: The effectiveness of antioxidant and zinc supplementation appears to differ by genotype. Further study is needed to determine the biological basis for this interaction. TRIAL REGISTRATION NUMBER: NCT00594672, pre-results.