Poster Topical Area: Aging and Chronic Disease

Location: Auditorium

Poster Board Number: 44

P01-024 - Gut dysfunction attenuates the anabolic response to feeding in patients with Chronic Obstructive Pulmonary Disease

Sunday, Jun 10
8:00 AM – 6:00 PM

Objectives: Gastrointestinal diseases and symptoms are prevalent in patients with Chronic Obstructive Pulmonary Disease (COPD), however the exact disturbances in gut function as well as its functional consequences remain unclear. This study investigates whether an impaired protein digestion capacity is present in COPD patients and, if so, to what extent it is associated with a reduced anabolic response to feeding and quality of life.

Methods: In 23 patients with moderate to severe COPD (GOLD stage II-IV) and 17 healthy control subjects, the stable tracers of Phenylalanine (PHE)-[ring-2H5] and Tyrosine (TYR)-[13C9,15N] were administered intravenously via primed constant and continuous infusion for 6 hours. Two hours after start of the infusion, a complete high protein meal containing PHE-[1-13C] and Spirulina-[U-15N] was ingested. Blood samples were taken and enrichments analysed by LC-MS/MS. The Spirulina-[U-15N] degradation ratio, as marker of protein digestion capacity, was calculated as the ratio of whole body rate of appearance of PHE-[15N] from Spirulina-[U-15N] to that of PHE-[1-13C]. The anabolic response to feeding was calculated both corrected and uncorrected for protein digestion capacity, and disease characteristics and outcome measures were assessed. Statistics was done by unpaired t-tests.

Results: The Spirulina-[U-15N] degradation ratio was 20% lower in the COPD than in the control group (0.65±0.03 vs. 0.81±0.04, p=0.002, respectively). The uncorrected net anabolic response to the meal was comparable between the COPD and control groups, but lower in COPD after correction for protein digestion capacity (32.6±3.3 vs. 52.1±5.4 umol/kg FFM*meal, p=0.003, respectively). Reduced protein digestion capacity was present particularly in COPD patients with high dyspnea severity (mMRC grades 3+4, p=0.038), exacerbation rate (p=0.052), current smokers (p=0.055) and oxygen users (p=0.060), and associated with reduced quality of life (SGRQ-C score, r:-0.74, p<0.0001).

Conclusions: The anabolic response to feeding is attenuated in COPD patients when taking into account their lower protein digestion capacity. Gut dysfunction is an important systemic component of COPD which needs to be considered when evaluating the response to nutritional support.

CoAuthors: Renate Jonker, PhD – Texas A&M University; Agata McNew-Wierzchowska – Texas A&M University; Eugene Veley, MD – Scott and White Medical Center; Rajesh Harrykissoon, MD – College Station Medical Center; Anthony Zachria, DO – College Station Medical Center; Nicolaas Deutz, MD, PhD – Texas A&M University

Marielle PKJ.. Engelen

Associate Professor
Texas A&M University
College Station, Texas