Efficacy of Vitamin C Supplementation on Chronic Obstructive Pulmonary Disease (COPD): A Systematic Review and Meta-Analysis

Ting Lei; Tingting Lu; Haichuan Yu; Xiaojie Su; Chuchu Zhang; Lei Zhu; Kehu Yang; Jian Liu

doi:10.2147/COPD.S368645

Efficacy of Vitamin C Supplementation on Chronic Obstructive Pulmonary Disease (COPD): A Systematic Review and Meta-Analysis

Int J Chron Obstruct Pulmon Dis. 2022 Sep 10:17:2201-2216. doi: 10.2147/COPD.S368645. eCollection 2022.

Authors

Ting Lei^#^{1

2}, Tingting Lu^#^{3

4}, Haichuan Yu^#^{1

2}, Xiaojie Su^{1

2}, Chuchu Zhang^{1

2}, Lei Zhu^{1

2}, Kehu Yang^{4

5}, Jian Liu^{1

2}

Affiliations

¹ Department of Clinical Medicine, The First Clinical Medical College of Lanzhou University, Lanzhou, 730000, People's Republic of China.
² Department of Critical Care Medicine, the First Hospital of Lanzhou University, Lanzhou, 730000, People's Republic of China.
³ Institute of Clinical Research and Evidence Based Medicine, Gansu Provincial Hospital, Lanzhou, 730000, People's Republic of China.
⁴ Evidence-Based Medicine Center, School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
⁵ Key Laboratory of Evidence-Based Medicine and Knowledge Translation of Gansu Province, Lanzhou, 730000, People's Republic of China.

^# Contributed equally.

Abstract

Background: In recent years, the pleiotropic roles of antioxidants have drawn extensive attention in various diseases. Vitamin C is a well-known antioxidant, and it has been used to treat patients with chronic obstructive pulmonary disease (COPD). This systematic review and meta-analysis aim to demonstrate the impact of vitamin C supplementation in patients with COPD.

Methods: We searched PubMed, Embase, Cochrane Library, Web of Science, Chinese National Knowledge Infrastructure (CNKI), SinoMed, Wanfang, and China Science and Technology Journal Database (cqvip.com) for eligible randomized controlled trials (RCTs) from their respective inception to May 18^th, 2021, by using the searching terms of COPD, vitamin C, and RCTs. A meta-analysis was performed to evaluate the effects of vitamin C on lung function, antioxidant levels, and nutritional conditions in COPD patients by using Review Manager (Version 5.4).

Results: Ten RCTs including 487 participants were eligible for our study. Meta-analysis results showed that vitamin C supplementation (≥400 mg/day) can significantly improve the forced expiratory volume in one second as a percentage (FEV1%) in COPD (SMD:1.08, 95% CI:0.03, 2.12, P=0.04). Moreover, vitamin C supplementation significantly improved the ratio of forced expiratory volume in 1 second and forced vital capacity (FEV1/FVC) (WMD:0.66, 95% CI: 0.26, 1.06, P=0.001), vitamin C level in serum (SMD:0.63, 95% CI: 0.02, 1.24, P=0.04) and glutathione (GSH) level in serum (SMD:2.47, 95% CI: 1.06, 3.89, P=0.0006). While no statistically significant difference was observed in body mass index (BMI), fat-free mass index (FFMI), vitamin E level and superoxide dismutase (SOD) level in serum.

Conclusion: Vitamin C supplementation could increase the levels of antioxidation in serum (vitamin C and GSH) and improve lung function (FEV1% and FEV1/FVC), especially in patients treated with vitamin C supplementation greater than 400 mg/day. However, further prospective studies are needed to explore the role of vitamin C in improving nutritional status.

Keywords: COPD; RCTs; lung function; meta-analysis; vitamin C.

Publication types

Meta-Analysis
Review
Systematic Review

MeSH terms

Antioxidants / adverse effects
Ascorbic Acid / adverse effects
Dietary Supplements / adverse effects
Glutathione
Humans
Pulmonary Disease, Chronic Obstructive* / diagnosis
Pulmonary Disease, Chronic Obstructive* / drug therapy
Superoxide Dismutase
Vitamin E
Vitamins

Substances

Antioxidants
Vitamins
Vitamin E
Superoxide Dismutase
Glutathione
Ascorbic Acid