TY - JOUR T1 - Early life vitamin D status and asthma and wheeze: a systematic review and meta-analysis. AU - Shen,Song-Ying, AU - Xiao,Wan-Qing, AU - Lu,Jin-Hua, AU - Yuan,Ming-Yang, AU - He,Jian-Rong, AU - Xia,Hui-Min, AU - Qiu,Xiu, AU - Cheng,Kar Keung, AU - Lam,Kin Bong Hubert, Y1 - 2018/07/20/ PY - 2017/02/14/received PY - 2018/06/25/accepted PY - 2018/7/22/entrez PY - 2018/7/22/pubmed PY - 2019/4/23/medline KW - Asthma KW - Fetal blood KW - Meta-analysis KW - Pregnancy KW - Systematic review KW - Vitamin D KW - Wheeze SP - 120 EP - 120 JF - BMC pulmonary medicine JO - BMC Pulm Med VL - 18 IS - 1 N2 - BACKGROUND: Vitamin D deficiency has been linked to an increased risk of asthma. This study aimed to quantify the effect of early life vitamin D status on asthma and wheeze later in life. METHODS: PubMed, Embase, CINAHL, and CNKI databases, the Cochrane Central Register of Controlled Trials, and Google Scholar were searched up to July 2017. We included randomized controlled trials (RCTs) and cohort studies with vitamin D level in blood (maternal or cord or infant) or intake (maternal intake during pregnancy or infant intake) and asthma and/or wheeze. Two reviewers independently extracted data. Fixed- and random-effects models were used to summarize the risk estimates of comparisons between highest vs. lowest vitamin D categories. RESULTS: Of the 1485 studies identified, three RCTs and 33 cohort studies were included. We did not include the RCTs (1619 participants) in the meta-analysis as the comparators and outcome definitions were heterogenous. Three RCTs reported a non-statistically significant effect of vitamin D supplementation during pregnancy on offspring wheeze/asthma at 3 years of age. Pooled estimates of cohort studies suggest no association between antenatal blood vitamin D levels or vitamin D intake and offspring asthma assessed either > 5 years or ≤ 5 years. The estimate for blood vitamin D remained unchanged when two studies assessing asthma in adulthood were excluded, but a significant inverse association emerged between vitamin D intake and childhood asthma. We found no association between antenatal vitamin D level and wheeze. On the other hand, vitamin D intake during pregnancy may have a protective effect against wheeze. CONCLUSIONS: The pooled estimates from cohort studies show no association between antenatal blood vitamin D level and asthma/wheeze in later life. Whereas, the pooled estimates from cohort studies suggest that antenatal vitamin D intake may have an effect on childhood asthma > 5 years or childhood wheeze. The inconsistent results from studies assessing vitamin D either in blood or intake may be explained by previously reported non-linear association between blood vitamin D3 and childhood asthma. Further trials with enough power and longer follow-up time should be conducted to confirm the results. SN - 1471-2466 UR - https://www.unboundmedicine.com/medline/citation/30029599/Early_life_vitamin_D_status_and_asthma_and_wheeze:_a_systematic_review_and_meta_analysis_ DB - PRIME DP - Unbound Medicine ER -