CHRONIC OBSTRUCTIVE PULMONARY-DISEASE STAGE AND HEALTH-RELATED QUALITY-OF-LIFE

Background: The American Thoracic Society recently recommended that ch ronic obstructive pulmonary disease be staged on the basis of the perc entage of predicted FEV1. Objective: To examine 1) the relation betwee n the American Thoracic Society system for staging chronic obstructive pulmonary disease and health-related quality of life and 2) the effec t of self-reported comorbid conditions on health-related quality of li fe. Design: Cross-sectional study. Setting: Outpatient clinics of resp iratory departments of four hospitals and one primary health care cent er in Spain. Patients: 321 consecutive male patients with chronic obst ructive pulmonary disease. Measurements: Functional respiratory impair ment, FEV1, respiratory symptoms, and health-related quality of life. Respiratory symptoms and health-related quality of life were measured by using the Spanish version of the St. George's Respiratory Questionn aire and the Nottingham Health Profile. Results: Patient scores on the St. George's Respiratory Questionnaire were moderately to strongly as sociated with disease staging (r = 0.27 to 0.51). Compared with refere nce values, values for health-related quality of life for patients wit h stage I disease were substantially higher on the St. George's Respir atory Questionnaire (6 and 34; P < 0.001) and values for impairment we re significantly greater in stage I patients with comorbid conditions (19 and 36; P = 0.001). At least one concomitant chronic condition was found in 84% of study patients. Comorbid conditions only partly influ enced the observed pattern of deterioration of health-related quality of life with worsening stages of disease. Conclusion: Staging criteria for chronic obstructive pulmonary disease based on percentage of pred icted FEV1 separated groups of patients with varying degrees of impair ment in health-related quality of life. Contrary to expectations, eve n patients with mild disease showed substantially compromised health-r elated quality of life. Comorbid conditions influenced the relation be tween chronic obstructive pulmonary disease and health-related quality of life.