Increased energy and/or protein intake improves anthropometry and muscle strength in COPD patients: a systematic review with meta-analysis on randomized controlled clinical trials.

Compromised nutritional status is associated with a poor prognosis in COPD patients. However, the impact of nutritional support in this group of patients is controversial. The present study systematically reviewed the effect of energy and or protein supplements or food fortification on anthropometry and muscle strength of COPD patients. We searched MEDLINE (PubMed), EMBASE, Cochrane Library, and Scopus for all published randomized clinical trials (RCTs) without language restriction up to May 2021. Three reviewers performed study selection and data extraction independently. We judged the risk of bias by RoB 2 and the certainty of evidence by the GRADE approach. We included thirty-two randomized controlled trials and compiled 31 of them (1,414 participants) in the random-effects model meta-analyses. Interventions were energy and/or protein oral nutritional supplements or food fortification added to the diet for at least one week. Pooled analysis revealed that nutritional interventions increased body weight (MD=1.44 kg, 95%CI 0.81 to 2.08, I2=73%), lean body mass (SMD=0.37; 95%CI 0.15 to 0.59, I2=46%), midarm muscle circumference (MD= 0.29 mm2, 95% CI 0.02 to 0.57, I2=0%), triceps skinfold (MD= 1.09 mm, 95% CI 0.01 to 2.16, I2=0%), and handgrip strength (SMD= 0.39, 95% CI 0.07 to 0.71, I2=62%) compared to control diets. Certainty of evidence ranged from very low to low, and most studies were judged with some concerns or at high risk of bias. This meta-analysis revealed, with limited evidence, that increased protein and/or energy intake positively impacts anthropometric measures and handgrip strength of COPD patients..PROSPERO CRD: 42020207577.