Centre for Primary Care and Public Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Department of Respiratory Medicine, Katholieke Universiteit, Leuven, Belgium.
Thorax. 2019 Apr;74(4):337-345. doi: 10.1136/thoraxjnl-2018-212092. Epub 2019 Jan 10.
Randomised controlled trials (RCTs) of vitamin D to prevent COPD exacerbations have yielded conflicting results.Individual participant data meta-analysis could identify factors that explain this variation.
PubMed, Embase, the Cochrane Central Register of Controlled Trials and Web of Science were searched from inception up to and including 5 October 2017 to identify RCTs of vitamin D supplementation in patients with COPD that reported incidence of acute exacerbations. Individual participant data meta-analysis was performed using fixed effects models adjusting for age, sex, Global Initiative for Chronic Obstructive Lung Disease spirometric grade and trial.
Four eligible RCTs (total 560 participants) were identified; individual participant data were obtained for 469/472 (99.4%) participants in three RCTs. Supplementation did not influence overall rate of moderate/severe COPD exacerbations (adjusted incidence rate ratio (aIRR) 0.94, 95% CI 0.78 to 1.13). Prespecified subgroup analysis revealed that protective effects were seen in participants with baseline 25-hydroxyvitamin D levels <25 nmol/L (aIRR 0.55, 95% CI 0.36 to 0.84) but not in those with baseline 25-hydroxyvitamin D levels ≥25 nmol/L (aIRR 1.04, 95% CI 0.85 to 1.27; p for interaction=0.015). Vitamin D did not influence the proportion of participants experiencing at least one serious adverse event (adjusted OR 1.16, 95% CI 0.76 to 1.75).
Vitamin D supplementation safely and substantially reduced the rate of moderate/severe COPD exacerbations in patients with baseline 25-hydroxyvitamin D levels <25 nmol/L but not in those with higher levels.
CRD42014013953.
随机对照试验（RCT）表明维生素 D 可预防 COPD 恶化，但结果存在差异。个体参与者数据的荟萃分析可以确定解释这种差异的因素。
从建立数据库到 2017 年 10 月 5 日，我们检索了 PubMed、Embase、Cochrane 对照试验中心注册库和 Web of Science，以确定报道 COPD 患者维生素 D 补充剂与急性加重发生率相关的 RCT。我们采用固定效应模型进行个体参与者数据荟萃分析，调整因素包括年龄、性别、慢性阻塞性肺疾病全球倡议肺功能分级和试验。
确定了 4 项符合条件的 RCT（总计 560 名参与者）；3 项 RCT 的 469/472（99.4%）名参与者获得了个体参与者数据。补充维生素 D 并未影响中重度 COPD 恶化的总体发生率（调整后的发病率比[aIRR]0.94，95%CI 0.78 至 1.13）。预先指定的亚组分析显示，在基线 25-羟维生素 D 水平<25nmol/L 的参与者中，补充维生素 D 具有保护作用（aIRR 0.55，95%CI 0.36 至 0.84），但在基线 25-羟维生素 D 水平≥25nmol/L 的参与者中无此作用（aIRR 1.04，95%CI 0.85 至 1.27；p 交互=0.015）。维生素 D 对至少发生 1 次严重不良事件的参与者比例无影响（调整后的 OR 1.16，95%CI 0.76 至 1.75）。
在基线 25-羟维生素 D 水平<25nmol/L 的患者中，维生素 D 补充剂安全且显著降低了中重度 COPD 恶化的发生率，但在基线 25-羟维生素 D 水平较高的患者中则无此作用。
CRD42014013953。
