Bandim Health Project, Indepth Network, Bissau, Guinea-Bissau.
PLoS One. 2011;6(8):e23265. doi: 10.1371/journal.pone.0023265. Epub 2011 Aug 11.
Within a randomised trial of neonatal vitamin A supplementation (VAS) in Guinea-Bissau, neonatal VAS did not affect overall infant mortality. We conducted a post-hoc analysis to test the hypothesis that neonatal VAS primes the response to subsequent vitamin A.
All trial children were offered VAS after follow-up ended at 1 year of age (FU-VAS). We compared mortality between 1 and 3 years of age according to initial randomization to neonatal VAS or placebo in Cox-regression models; we expected that children randomized to neonatal VAS compared with those randomized to placebo would have lower mortality after reception of FU-VAS.
Of 4345 infants enrolled in the original trial, 3646 lived in the study area at 1 year of age and 2958 received FU-VAS. Between 1 and 3 years of age, 112 children died. After FU-VAS, neonatal VAS was associated with lower mortality than placebo: Mortality Rate Ratio (MRR) = 0.54 (95%CI: 0.31-0.94). The effect was more pronounced in girls (MRR = 0.37 (0.16-0.89)) than boys (MRR = 0.73 (0.35-1.51)). The beneficial effect of neonatal VAS may have been particularly strong for girls who received both VAS in a campaign and FU-VAS (MRR = 0.15 (0.03-0.67)). Among children who had not received FU-VAS, mortality in the second and third year of life did not differ according to reception of neonatal VAS or placebo. Hence, in the second and third year of life the effect of neonatal VAS versus placebo was different in girls who had or had not received FU-VAS (p for homogeneity = 0.01).
The present results suggest that neonatal VAS primes the response in girls such that they get a beneficial effect after a subsequent dose of VAS.
Clinicaltrials.gov NCT00168597.
在几内亚比绍进行的新生儿维生素 A 补充随机试验中，新生儿维生素 A 补充并未影响整体婴儿死亡率。我们进行了一项事后分析，以检验假设，即新生儿维生素 A 补充可增强对随后维生素 A 补充的反应。
所有试验儿童在 1 岁随访结束后（FU-VAS）均接受维生素 A 补充。我们在 Cox 回归模型中比较了 1 至 3 岁期间的死亡率，根据初始随机分组接受新生儿维生素 A 补充或安慰剂；我们预计与接受安慰剂的儿童相比，接受新生儿维生素 A 补充的儿童在接受 FU-VAS 后死亡率较低。
在最初的试验中，4345 名婴儿中，3646 名在 1 岁时居住在研究区域，2958 名接受了 FU-VAS。在 1 至 3 岁期间，有 112 名儿童死亡。在接受 FU-VAS 后，新生儿维生素 A 补充与安慰剂相比死亡率较低：死亡率比（MRR）=0.54（95%CI：0.31-0.94）。这种效果在女孩中更为明显（MRR=0.37（0.16-0.89）），而在男孩中则不明显（MRR=0.73（0.35-1.51））。对于在一次运动中既接受了维生素 A 补充又接受了 FU-VAS 的女孩，新生儿维生素 A 补充的有益效果可能特别强（MRR=0.15（0.03-0.67））。对于未接受 FU-VAS 的儿童，在第二年和第三年的生命中，接受或未接受新生儿维生素 A 补充的死亡率没有差异。因此，在第二年和第三年的生命中，接受新生儿维生素 A 补充与安慰剂相比的效果在接受或未接受 FU-VAS 的女孩中不同（同质检验的 p 值为 0.01）。
目前的结果表明，新生儿维生素 A 补充可增强女孩的反应，使她们在接受随后的维生素 A 补充后获得有益效果。
Clinicaltrials.gov NCT00168597。
