Impact of fatigue in patients with chronic obstructive pulmonary disease: results from an exploratory study.

Introduction: Fatigue, which is also present in the healthy population, is a common but understudied symptom in chronic obstructive pulmonary disease (COPD). We hypothesized that clinically significant fatigue is also frequent in COPD and can be associated with an increased disease burden.

Methods: An exploratory analysis derived from an ongoing cross-sectional study was carried out to evaluate levels of fatigue and impact on health-related quality of life/health status in patients with COPD (COPD group; n = 20) and healthy subjects (control group; n = 5). Health-related quality of life was measured using the Short Form Health Survey 36 (SF-36), health status with the Clinical COPD Questionnaire (CCQ), and airways obstruction with postbronchodilator forced expiratory volume in 1 s (FEV1 %predicted). Fatigue was measured with the vitality score of the SF-36, its clinical significance being defined by values of 50 or less. Fatigue was also measured using the Functional Assessment of Chronic Illness Therapy scale for fatigue (FACIT-F).

Results: Vitality scores were significantly worse in the COPD group (45.60 versus 76.25; p = 0.004). FACIT-F scores were significantly lower in the COPD group versus the control group (74.5 versus 95.0; p = 0.03). Clinically significant fatigue was detected in 60% of the COPD group, and was associated with a worse FEV1 %predicted (47.71 versus 65.82%; p = 0.016), worse symptoms burden (CCQ symptoms score 3.75 versus 2.43; p = 0.019), and worse overall health status (CCQ total score 3.30 versus 2.11; p = 0.011). Its link with systemic inflammation remains to be clarified further.

Conclusions: Clinically significant fatigue is common among patients with COPD and is associated with an increased disease burden. It should therefore be integrated as a measure of disease prognosis and control in patients with COPD.