Vitamin D supplementation for preventing infections in children under five years of age

NEW

Mohammad Y Yakoob1, Rehana A Salam2, Farhan R Khan3, Zulfiqar A Bhutta4

1. Harvard School of Public Health, Departments of Epidemiology and Nutrition, Boston, MA, USA
2. Aga Khan University Hospital, Division of Women and Child Health, Karachi, Sind, Pakistan
3. Aga Khan University Hospital, Department of Surgery, Karachi, Sindh, Pakistan
4. Hospital for Sick Children, Center for Global Child Health, Toronto, ON, Canada

Yakoob MY, Salam RA, Khan FR, Bhutta ZA. Vitamin D supplementation for preventing infections in children under five years of age. Cochrane Database of Systematic Reviews 2016, Issue 11. Art. No.: CD008824. DOI: 10.1002/14651858.CD008824.pub2.

To read the full-text article, please click here: DOI: 10.1002/14651858.CD008824.pub2

Background

Vitamin D is a micronutrient important for bone growth and immune function. Deficiency can lead to rickets and has been linked to various infections, including respiratory infections. Several studies have reported an association between vitamin D deficiency and infections among children, and is thought to be related to the role of vitamin D in the immune system. In this systematic review, Cochrane researchers examined the role of vitamin D supplementation in prevention of infections in children under five years of age. The researchers studied the infections of pneumonia, tuberculosis (TB), diarrhoea, and malaria in this review.

Study characteristics

The review authors examined the available evidence up to 17 June 2016, and included four trials with a total of 3198 children under five years of age. The included trials were conducted in Afghanistan, Spain and the USA.

Key findings

The review did not detect an effect of vitamin D supplementation on death (low quality evidence); the occurrence of the first or only episode of pneumonia; or on children with pneumonia, irrespective of whether this had been confirmed by hospital tests (moderate quality evidence). Limited evidence showed that there was no obvious difference in the first or repeat episodes of diarrhoea between supplemented and unsupplemented children. We do not know about whether Vitamin D influences hospital admissions as there was only one small study measuring this (very low quality evidence). The mean serum vitamin D concentrations were higher in the supplemented versus unsupplemented children at the end of supplementation period (low quality evidence). One large trial from Afghanistan showed an increase in repeat episodes of confirmed pneumonia but not on confirmed and unconfirmed pneumonia. None of the included trials reported on TB or malaria as outcomes.

Conclusions

One large trial has not demonstrated an effect of vitamin D on death or respiratory infections in children under five years of age. We did not find trials evaluating Vitamin D supplementation to prevent other infections such as TB and malaria.