维生素 D 对慢性阻塞性肺疾病（COPD）患者呼吸功能和免疫状况的影响：系统评价和荟萃分析。

BACKGROUND: Many studies have demonstrated that vitamin D has clinical benefits when used to treat patients with chronic obstructive pulmonary disease (COPD). However, most of these studies have insufficient samples or inconsistent results. The aim of this meta-analysis was to evaluate the effects of vitamin D therapy in patients with COPD. METHODS: We performed a comprehensive retrieval in the following electronic databases: PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Data, and Chinese Scientific Journals Database (VIP). Two trained reviewers identified relevant studies, extracted data information, and then assessed the methodical quality by the Cochrane risk of bias assessment tool, independently. Then, the meta-analyses were conducted by RevMan 5.4, binary variables were represented by risks ratio (RR), and continuous variables were represented by mean difference (MD) or standardized mean difference (SMD) to assess the efficacy of vitamin D therapy in patients with COPD. Then, publication bias assessment was conducted by funnel plot analysis. Finally, the quality of evidence was assessed by the GRADE system. RESULTS: A total of 15 articles involving 1598 participants were included in this study. The overall results showed a statistical significance of vitamin D therapy in patients with COPD which can significantly improve forced expiratory volume in 1 second (FEV1) (MD: 5.69, 95% CI: 5.01-6.38, < 0.00001,I2 = 51%) and FEV1/FVC (SMD:0.49, 95% CI: 0.39-0.60, < 0.00001,I2 = 84%); and serum 25 (OH)D (SMD:1.21, 95% CI:1.07-1.34, < 0.00001,I2 = 98%) also increase CD3+ Tcells (MD: 6.67, 95% CI: 5.34-8.00, < 0.00001,I2 = 78%) and CD4+ T cells (MD: 6.00, 95% CI: 5.01-7.00, < 0.00001,I2 = 65%); and T lymphocyte CD4+/CD8+ ratio (MD: 0.41, 95% CI: 0.20-0.61, = 0.0001,I2 = 95%) obviously decrease CD8+ Tcells(SMD: -0.83, 95% CI: -1.05- -0.06, < 0.00001,I2 = 82%), the times of acute exacerbation (RR: 0.40, 95% CI: 0.28-0.59, < 0.00001,I2 = 0%), and COPD assessment test (CAT) score (MD: -3.77, 95% CI: -5.86 - -1.68, = 0.0004,I2 = 79%). CONCLUSIONS: Our analysis indicated that vitamin D used in patients with COPD could improve the lung function (FEV1 and FEV1/FVC), the serum 25(OH)D, CD3+ T cells, CD4 + T cells, and T lymphocyte CD4+/CD8+ ratio and reduce CD8+ T cells, acute exacerbation, and CAT scores.

背景：许多研究表明，维生素 D 治疗慢性阻塞性肺疾病（COPD）患者具有临床益处。然而，这些研究大多数样本量不足或结果不一致。本荟萃分析旨在评估维生素 D 治疗 COPD 患者的效果。

方法：我们在以下电子数据库中进行了全面检索：PubMed、Embase、Cochrane 图书馆、中国国家知识基础设施（CNKI）、万方数据和中国科学期刊数据库（VIP）。两名经过培训的评审员确定了相关研究，提取数据信息，并使用 Cochrane 偏倚风险评估工具独立评估方法学质量。然后，使用 RevMan 5.4 进行荟萃分析，二分类变量表示为风险比（RR），连续变量表示为均数差（MD）或标准化均数差（SMD），以评估维生素 D 治疗 COPD 患者的疗效。然后，通过漏斗图分析进行发表偏倚评估。最后，使用 GRADE 系统评估证据质量。

结果：共纳入 15 篇文章，涉及 1598 名参与者。总体结果表明，维生素 D 治疗 COPD 患者具有统计学意义，可显著改善第 1 秒用力呼气量（FEV1）（MD：5.69，95%CI：5.01-6.38，<0.00001，I2=51%）和 FEV1/FVC（SMD：0.49，95%CI：0.39-0.60，<0.00001，I2=84%）；血清 25（OH）D（SMD：1.21，95%CI：1.07-1.34，<0.00001，I2=98%）也增加 CD3+T 细胞（MD：6.67，95%CI：5.34-8.00，<0.00001，I2=78%）和 CD4+T 细胞（MD：6.00，95%CI：5.01-7.00，<0.00001，I2=65%）；T 淋巴细胞 CD4+/CD8+比值（MD：0.41，95%CI：0.20-0.61，=0.0001，I2=95%）明显降低 CD8+T 细胞（SMD：-0.83，95%CI：-1.05-0.06，<0.00001，I2=82%），急性加重次数（RR：0.40，95%CI：0.28-0.59，<0.00001，I2=0%）和 COPD 评估测试（CAT）评分（MD：-3.77，95%CI：-5.86-0.68，=0.0004，I2=79%）。

结论：我们的分析表明，维生素 D 可改善 COPD 患者的肺功能（FEV1 和 FEV1/FVC）、血清 25（OH）D、CD3+T 细胞、CD4+T 细胞和 T 淋巴细胞 CD4+/CD8+比值，降低 CD8+T 细胞、急性加重和 CAT 评分。