The effects of various nutritional supplements in patients with chronic obstructive pulmonary disease: a network meta-analysis.

OBJECTIVE

To evaluate the effectiveness of various nutritional supplements as interventions for patients with Chronic Obstructive Pulmonary Disease (COPD) using network meta-analysis.

METHODS

We searched PubMed, Embase, Cochrane Library, and Web of Science databases for randomized controlled trials on nutritional supplements for COPD patients, with the search updated to March 24, 2025. The risk of bias for each included study was assessed using appropriate tools, and the certainty of evidence was evaluated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Data synthesis was performed using R software, employing network meta-analysis methods to compare the relative efficacy of different nutritional interventions.

RESULTS

Thirty-seven studies involving 1975 COPD patients and 21 different nutritional supplements were analyzed. Butyrate [MD = 2.7, 95% CrI (1.0, 4.4)], Nanocurcumin [MD = 13, 95% CrI (5.4, 21)], and probiotics [MD = 7.1, 95% CrI (5.2, 9.1)] significantly improved Forced Expiratory Volume in One Second (FEV1). Nanocurcumin also slowed the decline in the ratio of Forced Expiratory Volume in One Second to Forced Vital Capacity (FEV1/FVC) [MD = 12, 95% CrI (5.5, 18)]. For exercise endurance, coenzyme Q10 combined with creatine [MD = 63, 95% CrI (36, 90)], Melatonin (MLT) [MD = 46, 95% CrI (1.3, 92)], Nitrate [MD = 30, 95% CrI (19, 41)], and whey proteins [MD = 11, 95% CrI (9.2, 13)] significantly improved 6-minute walk distance (6MWD). Regarding dyspnea reduction, MLT [MD = -0.90, 95% CrI (-1.6, -0.21)] and Yam-Epimedium [MD = -1.3, 95% CrI (-1.9, -0.67)] significantly lowered modified Medical Research Council (mMRC) scores. In terms of quality of life, MLT [MD = -8, 95% CrI (-12, -4.2)], Vitamin D (VD) [MD = -2.5, 95% CrI (-3.1, -1.9)], and whey proteins [MD = -0.70, 95% CrI (-0.99, -0.41)] reduced COPD Assessment Test (CAT) scores. Additionally, AKL1 [MD = -9.2, 95% CrI (-18, -0.41)], creatine [MD = -9.6, 95% CrI (-17, -2.8)], and Yam-Epimedium [MD = -24, 95% CrI (-34, -13)] lowered St. George's Respiratory Questionnaire (SGRQ) scores. The Surface Under the Cumulative Ranking Curve (SUCRA) analysis showed Nanocurcumin ranked highest for improving FEV1/FVC, coenzyme Q10 combined with creatine for 6MWD, Yam-Epimedium for reducing dyspnea and SGRQ, and MLT for lowering CAT scores.

CONCLUSION

This analysis indicates that various nutritional supplements, including Nanocurcumin, butyrate, probiotics, coenzyme Q10 combined with creatine, MLT, nitrate, whey proteins, VD, AKL1, creatine, and Yam-Epimedium, can potentially benefit COPD patients, demonstrating differing levels of effectiveness. Specifically, Nanocurcumin may be the best choice for improving lung function; coenzyme Q10 combined with creatine may be the most effective for enhancing exercise endurance; Additionally, Yam-Epimedium is the most likely supplement to reduce the symptoms of dyspnea in COPD patients. Yam-Epimedium and MLT may be the most effective for improving quality of life and overall health status.