Effect of enteral zinc supplementation on growth and neurodevelopment of preterm infants: a systematic review and meta-analysis.

OBJECTIVE To evaluate effect of enteral zinc supplementation on growth and neurodevelopmental outcomes of preterm infants. STUDY DESIGN A systematic review and meta-analysis of randomized-controlled trials (RCTs) examining growth and neurodevelopmental outcomes after zinc supplementation in preterm infants. RESULTS Of eight RCTs involving 742 infants included, seven reported growth anthropometrics at 3-6 months corrected age (CA) and two reported neurodevelopmental outcomes at 6-12 months CA. Zinc supplementation was associated with increased weight z-score (weighted mean difference (WMD) = 0.50; 95% CI 0.23-0.76, heterogeneity I2 = 89.1%; P < 0.01), length z-score (WMD = 1.12; 95% CI 0.63-1.61, heterogeneity I2 = 96.0%; P < 0.01) and motor developmental score (WMD = 9.54; 95% CI 6.6-12.4 heterogeneity I2 = 0%; P = 0.52). There was no effect on head circumference and total developmental score. Evidence is "moderate" certainty for weight and length and "very low" certainty for neurodevelopment. CONCLUSION Zinc supplementation may enhance weight gain and linear growth in preterm infants. There is a lack of data about relationship between zinc supplementation and neurodevelopment.