[Meta-analysis of energetic nutritional intervention for stable chronic obstructive pulmonary disease patients]

To conduct a meta-analysis of randomized controlled trials (RCTs) to clarify whether nutritional intervention (caloric supplementation for at least 2 weeks) can improve the nutritional status and the pulmonary functions, while reduce the frequency of acute exacerbation or mortality of patients with stable COPD.

RCTs were identified from databases including Medline and Embase, and a hand search for references was also conducted. Two reviewers independently selected the trials for inclusion, assessed the methodological quality of each study, and extracted the data Within each trial and for each outcome, an effect size was calculated. The effect sizes were then pooled by a random or fixed effects model according to the heterogeneity tested among the studies.

From 143 references, 10 RCTs (including 354 participants) were included in this meta-analysis. The results of the study, which included body weight (BW), mid arm muscle circumference (MAMC), triceps skinfold thickness (TSF), forced expiratory volume in one second (FEV1) and forced vital capacity (FVC), were expressed in standardized mean difference (SMD, 95% CI): 0.05 (-0.18 - 0.28) kg, -0.16 (-0.57 - 0.25) cm, 0.41 (0.01 - 0.82) cm, 0.04 (-0.39 - 0.48) ml and 0.03 (- 0.40 - 0.46) ml. The effect of energetic nutritional intervention for patients with stable COPD was insignificant; the 95% CI around the pooled effect sizes all included zero.

Nutritional intervention by caloric supplementation had no effect on improving the nutritional status and the pulmonary functions in patients with stable COPD. There was no evidence that the frequency of acute exacerbation or mortality could be reduced.