Størdal Ketil, Lundeby Karen M, Brantsæter Anne L, Haugen Margaretha, Nakstad Britt, Lund-Blix Nicolai A, Stene Lars C
*Norwegian Institute of Public Health, Oslo †Paediatric Department, Ostfold Hospital Trust, Grålum ‡Oslo University Hospital, Children's Center, Oslo §Department of Pediatric and Adolescent Medicine, Akershus University Hospital, Nordbyhagen ||Department of Pediatric Research, Oslo University Hospital, Rikshospitalet, Oslo, Norway.
J Pediatr Gastroenterol Nutr. 2017 Aug;65(2):225-231. doi: 10.1097/MPG.0000000000001539.
Breast-feeding may protect against infections, but its optimal duration remains controversial. We aimed to study the association of the duration of full and any breast-feeding with infections the first 18 months of life.
The Norwegian Mother and Child study (MoBa) is a prospective birth cohort which recruited expecting mothers giving birth from 2000 to 2009. We analyzed data from the full cohort (n = 70,511) and sibling sets (n = 21,220) with parental report of breast-feeding and infections. The main outcome measures were the relative risks (RRs) for hospitalization for infections from 0 to 18 months by age at introduction of complementary foods and duration of any breast-feeding.
Although we found some evidence for an overall association between longer duration of full breast-feeding and lower risk of hospitalizations for infections, 7.3% of breast-fed children who received complementary foods at 4 to 6 months of age compared to 7.7% of those receiving complementary foods after 6 months were hospitalized (adjusted RR 0.95, 95% confidence interval 0.88-1.03). Higher risk of hospitalization was observed in those breast-fed 6 months or less (10.0%) compared to ≥12 months (7.6%, adjusted RR 1.22, 95% confidence interval 1.14-1.31), but with similar risks for 6 to 11 months versus ≥12 months. Matched sibling analyses, minimizing the confounding from shared maternal factors, showed nonsignificant associations and were generally weaker compared with the cohort analyses.
Our results support the recommendation to fully breast-feed for 4 months and to continue breast-feeding beyond 6 months, and suggest that protection against infections is limited to the first 12 months.
母乳喂养可能预防感染，但其最佳持续时间仍存在争议。我们旨在研究纯母乳喂养和任何形式母乳喂养的持续时间与生命最初18个月内感染之间的关联。
挪威母婴研究（MoBa）是一项前瞻性出生队列研究，招募了2000年至2009年分娩的孕妇。我们分析了整个队列（n = 70,511）和同胞组（n = 21,220）的数据，这些数据包含父母报告的母乳喂养和感染情况。主要结局指标是引入辅食时的年龄和任何形式母乳喂养的持续时间与0至18个月感染住院的相对风险（RRs）。
尽管我们发现了一些证据表明较长时间的纯母乳喂养与较低的感染住院风险之间存在总体关联，但4至6个月接受辅食的母乳喂养儿童中有7.3%住院，而6个月后接受辅食的儿童中有7.7%住院（调整后的RR为0.95，95%置信区间为0.88 - 1.03）。与母乳喂养≥12个月的儿童（7.6%）相比，母乳喂养6个月及以下的儿童住院风险更高（10.0%，调整后的RR为1.22，95%置信区间为1.14 - 1.31），但6至11个月与≥12个月的风险相似。配对同胞分析将共享母亲因素的混杂降至最低，显示出无显著关联，且与队列分析相比通常较弱。
我们的结果支持纯母乳喂养4个月并在6个月后继续母乳喂养的建议，并表明预防感染的作用仅限于最初12个月。
