title: Effect of nutritional status on exercise performance in patients with chronic obstructive pulmonary disease.
abstract: The purpose of our study was to examine the nutritional status of patients with severe chronic obstructive pulmonary disease (COPD) (mean predicted FEV1, 30 +/- 11%) and to explore its relationship to functional capacity. Functional capacity was evaluated by measuring peak oxygen consumption (VO2max) using an incremental cycle ergometry test, a 6-min walk test, self-perceived level of dyspnea, and quality of life. The percentage ideal body weight (%IBW) was less than 90% in 33 of 135 subjects. Triceps skinfold thickness was less than 60% of normal in 19 of 33 of these subjects. Total lymphocyte count was not different between groups, whereas hemoglobin (14.9 versus 15.9 g/dl) and albumin (4.0 versus 4.1 g/dl) were marginally reduced in underweight subjects. Dyspnea and overall quality of life were unaffected by nutritional status. Maximal inspiratory (Pimax) and expiratory mouth pressures (PEmax) were weakly associated with %IBW (R2 = 0.04; p = 01 and R2 = 0.15; p less than 0.01, respectively). The %IBW was a predictor of VO2max (percent predicted) after controlling for FEV1 in regression analysis (partial R2 = 0.08; p less than 0.001). Despite the association of weight status with VO2max, the 6-min walk was not influenced by %IBW. The perceived intensity of exercise as judged by the Borg score was far greater with the bicycle exercise that with the 6-min walk (mean score, 10.6 +/- 1.2 versus 4.6 +/- 1.9). This was supported by the difference in heart rate after these two tests.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Gray-Donald
authors.forename: L
authors.initials: L
authors.lastname: Gibbons
authors.forename: S H
authors.initials: SH
authors.lastname: Shapiro
authors.forename: J G
authors.initials: JG
authors.lastname: Martin
mesh_terms: D001835:Body Weight; D005541:Forced Expiratory Volume; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008875:Middle Aged; D009752:Nutritional Status; D005082:Physical Exertion; D011788:Quality of Life; D015656:Respiratory Mechanics