[Clinical benefit of nutritional assessment and support in patients with chronic obstructive pulmonary disease]

Weight loss is common in patients with chronic obstructive pulmonary disease (COPD). Comprehensive nutritional assessment was conducted in two large groups of patients with COPD who were enrolled in the Respiratory Failure Research Program sponsored by the Japanese Ministry of Health and Welfare and the Kinki COPD Research Group. The incidences of mild malnutrition (%IBW < 90%) were 74% and 62%, respectively. The incidences of hypoalbuminemia were low: 10.0% and 6.5%, respectively. The incidence of imbalance in plasma amino acids, which was defined as an abnormally low BCAA/AAA ratio, was as high as 93% in patients with COPD and chronic respiratory failure. The %IBW was significantly related to the FEV1 and to the DLco/VA. The moderately-malnourished subpopulation was characterized by a greater degree of hyperinflation and hypercapnea: the measured resting energy expenditure (REE) was significantly higher than the values in age-matched healthy controls. REE/REEpred was significantly and inversely related to BCAA/AAA and to Pimax. REE was inversely related to FEV1%. REE in the subgroup with severe hyperinflation was significantly higher than REE in those with milder hyperinflation. Among patients with an FEV1% of less than 50%, mortality tended to be higher in those with lower body weight, and this relationship was stronger in patients with an FEV1% of more than 50%. When patients were given a BCAA-enriched enteral formula in addition to their usual diet for 3 months, there was a significant increase in body weight, transferrin level, and Pimax.