The prevalence and determinants of nutritional changes in chronic obstructive pulmonary disease

Sixty outpatients with chronic obstructive pulmonary disease underwent nutritional, physiologic, and psychologic evaluation to determine the prevalence of nutritional depletion and the relationship to physiologic and psychologic factors. Weight loss was reported in 27 percent. Triceps skinfolds (TSF) were less than 60 percent of standard in 33 percent, none had mid-arm muscle circumference (MAMC) less than 60 percent of standard, and 5 percent had body weight (BW) less than 60 percent of ideal. Values for BW-percent of ideal, TSF-percent of standard, and MAMC-percent of standard were inversely correlated with the percent of estimated caloric expenditure ingested. Also, BW percent was correlated with FEV1 percent predicted, diffusion capacity percent predicted, and oxygen consumption/kg at rest (VO2 percent/kg). There were five variables that explained 62.6 percent of the variation in BW percent: VO2/kg at rest explained 22.2 percent; ventilatory equivalent 13.5 percent; PaCO2 9.8 percent; log vital capacity percent predicted 9.2 percent; and depression 7.8 percent. It is concluded that increased caloric utilization without adequate compensation in dietary intake is the reason for nutritional depletion.