Respiratory function and self-reported functional health: EPIC-Norfolk population study

Respiratory function is known to be associated with mortality. However, its association with health related quality of life (HRQoL) has not yet been examined. A population-based cross sectional study was conducted in 16,738 subjects aged 40-79 yrs and resident in Norfolk, to examine the association between forced expiratory volume in one second (FEV1) and HRQoL measured by the 36-item short form questionnaire. Individuals who were in the highest quintiles of FEV1 were more likely to report good physical functional health (odds ratio (OR) 1.60; 95% confidence interval (CI) 1.28-2.01 and OR 1.71; 95% CI 1.40-2.10 for males and females, respectively) controlling for age, height, weight or body mass index, smoking, physical activity, prevalent illness and social class. Being in the highest quintile for FEV1 was associated with significantly lower likelihood of poor self-reported mental functional health status in males (OR 0.78; 95% CI 0.61-0.99), but not in females (OR 1.00; 95% CI 0.82-1.22). In conclusion, forced expiratory volume in one second independently predicts self perceived physical well being in a general population across the whole normal distribution of respiratory function.