Nutritional status as a predictor of mortality in severe chronic obstructive pulmonary disease

In order to determine the role of nutritional status as a predictor of mortality in patients with chronic obstructive pulmonary disease (COPD), 348 patients with severe airway obstruction were followed for 1 to 3 years. Baseline measurements were done on patients recruited for a clinical trial of negative pressure ventilation in severe COPD. When adjusted for the severity of disease, as assessed by the forced expiratory volume in one second (FEV$ sb1$) and the use of oxygen therapy, body mass index (BMI) was a significant predictor of mortality in the recruited group. The relative risk (RR) for BMI comparing the 25$ sp{ rm th}$ to the 75$ sp{ rm th}$ percentile was 1.86 (1.76, 1.97). Both BMI and triceps skinfold thickness (TSF) were the nutritional parameters which significantly predicted mortality in the subgroup of randomized patients when adjusted for the partial pressure of carbon dioxide in arterial blood (PaCO$ sb2$) and use of oxygen therapy. The RR's comparing the 25$ sp{ rm th}$ to the 75$ sp{ rm th}$ percentile for BMI and TSF respectively, were 2.09 (1.92, 2.27) and 1.80 (1.66, 1.96)