Anthropometric and pulmonary function test profiles of outpatients with stable chronic obstructive pulmonary disease

To determine the prevalence of abnormalities in the nutritional status, and their correlation with pulmonary function test results, in a population of outpatients with stable chronic obstructive pulmonary disease (COPD).

During 1 year of study, body weight, height, triceps skinfold, arm muscle circumference, and pulmonary function parameters were assessed in 126 patients. On the basis of body mass index (BMI = weight/height2) of less than 20, 20 to 27, and greater than 27, the patients were divided into underweight (n = 29, 23%), normal weight (n = 67, 53.2%), and overweight (n = 30, 23.8%), respectively.

Diffusing capacity for carbon monoxide (DLCO), both as absolute and percent predicted, differed significantly among the three groups, being lowest in the underweight and highest in the overweight patients. A significant and positive correlation was present between BMI as the independent variable and DLCO, forced expiratory volume in 1 second, and its ratio to forced vital capacity. A significant and negative correlation existed between BMI and residual volume and its ratio to total lung capacity.

A substantial number of stable COPD patients (46.8%) have nutritional abnormalities. BMI is a simple and accurate indicator of nutritional status in these patients. BMI correlates significantly with some tests of pulmonary function.