Repeatability and methodology of resting energy expenditure in patients with cystic fibrosis

In this study, intra-individual variation of resting energy expenditure (RE E) in adults with cystic fibrosis (CF) and the effect of measurement durati on were determined. Twelve adults with CF and chronic Pseudomonas aeruginos a (Ps. aeruginosa) infection and 12 healthy volunteers, matched for age and sex were studied whilst clinically stable on days 1, 2, and 15. Respirator y gas exchange was monitored by continuous measurement of oxygen uptake ((V ) over dot (O2)) and carbon dioxide production ((V) over dot (CO2)) using a ventilated hood indirect calorimeter. Coefficients of variation (CVs) were 4.3% in patients and 2.4% in controls comparing days 1 and 2. The CV for p atients was 5.0% and for controls 2.9% comparing days I and 15. The effect of measurement duration on REE was assessed in eight of the CF patients. RE E remained stable for 40 min but tended to rise by 80 min. Plasma catechola mine concentrations were stable between study days in patients but fell wit h time in controls suggesting some adaptation to experimental procedure. Th e seater variability of REE in patients was related to change in serum CRP over 2 weeks. REE is a repeatable measurement in clinically stable patients with CF, though variability was greater in patients than healthy subjects. This has implications for the design and interpretation of longitudinal st udies of REE in patients with chronic lung disease. (C) 1999 Elsevier Scien ce B.V. All rights reserved.