Chronic obstructive pulmonary disease (COPD) is one of the most important and prevalent diseases suffered by the elderly. Evidence exists that its onset and severity might be conditioned by antioxidant status. The aim of the present study was to investigate the relationship between antioxidant status and COPD in institutionalised elderly people. In all, 183 elderly people aged >65 years (twenty-one had COPD and 160 healthy controls) were studied. The subjects’ diets were investigated via the use of precise individual weighing for 7 d. Body weight, height, and biceps and triceps skinfold thickness were measured, and body fat (kg) and BMI (kg/m2) were calculated. Serum retinol, α-tocopherol, β-carotene and vitamin C levels were determined. Subjects with COPD ate less fruits than healthy controls (117 (sd 52) v. 192 (sd 161) g/d), their coverage of the recommended intake of vitamin C was smaller (150 (sd 45) v. 191 (sd 88) %; note that both exceeded 100 %) and their diets had a lower antioxidant capacity (6558 (sd 2381) v. 9328 (sd 5367) mmol trolox equivalent/d). Those with COPD had lower serum vitamin C and α-tocopherol concentrations than healthy controls (32·4 (sd 15·3) v. 41·5 (sd 14·8) µmol/l and 12·1 (sd 3·2) v. 13·9 (sd 2·8) µmol/l, respectively). In addition, subjects with α-tocopherol <14·1µmol/l (50th percentile) were at 6·43 times greater risk of having COPD than those subjects with ≥14·1µmol/l (OR 6·43; 95 % CI 1·17, 35·24; P<0·05), taking sex, age, use of tobacco, body fat and vitamin E intake as covariables. Subjects with COPD had diets of poorer antioxidant quality, especially with respect to vitamins C and E, compared with healthy controls.
