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Kintampo Health Research Centre
Kintampo, Ghana
E-mail: sam.newton{at}ghana-khrc.org
London School of Hygiene and Tropical Medicine
London
United Kingdom
Dear Sir:
We are writing to comment on the publication entitled "Randomized controlled safety and efficacy trial of 2 vitamin A supplementation schedules in Tanzanian infants" by Idindili et al (1), which was recently published in the Journal.
We conducted a similar trial in Kintampo, Ghana, and our study and that by Idindili et al conducted in Tanzania were both funded by the World Health Organization in 2002. Both studies assessed the effectiveness of a new maternal and young infant vitamin A dosing regimen, in which mothers and infants in the intervention arm were given 400 000 IU vitamin A within 6 wk of delivery, and their infants were given 50 000 IU vitamin A at 6, 10, and 14 wk of age as recommended in the Annecy Accords (2). Mothers and infants in the control arm were given the old regimen of 200 000 IU vitamin A within 6 wk of delivery, and their infants received 25 000 IU vitamin A at 6, 10, and 14 wk along with DPT (diphtheria-pertussis-tetanus) immunizations.
The effect of the 2 supplementation regimens on breast-milk retinol concentrations and on infant serum retinol concentrations, assessed by using modified-relative-dose-response tests, were assessed at 6 wk, 6 mo, and 9 mo of age. The incidence of side effects, such as bulging of the anterior fontanel, vomiting, and incidence of severe morbidity, were also measured at these ages.
Our results were similar to those of the Tanzanian study, but were only available for a small number of infants who were enrolled early in the trial because the routine monitoring of capsule content showed degradation of some vitamin A capsules. The vitamin A capsules used in both trials came from the same source. The capsules used in the Tanzania study also underwent degradation; however, enrollment in the Tanzanian trial was completed before the degradation occurred; the Ghanian trial started a year later.
The conclusion of both trials was that a regimen of 50 000IU vitamin A with early infant vaccines has no advantage over the previously recommended regimen of 25 000 IU, which has important policy implications.
The combined evidence from those trials and the original World Health Organization multicenter trials (3) in Ghana, India, and Peru suggests no overall benefit of vitamin A supplementation in combination with vaccines in the first 5 mo of life. Indeed, it is no longer a policy recommendation to do so; the emphasis remains on larger doses to older children.
However, these trials also raise questions about the stability of capsules being used in vitamin A supplementation programs and the need to monitor their retinol content to ensure that young children actually receive adequate amounts of vitamin A.
ACKNOWLEDGMENTS
The authors had no conflicts of interest.
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