Determinants and impact of fatigue in patients with chronic obstructive pulmonary disease

The perception of fatigue in COPD has been associated with reduced health status. We have shown that exacerbations are associated with reduced activity and health status. However, the relationship between fatigue and exacerbation is unknown.

To investigate the hypothesis that increased fatigue is related to physical inactivity and COPD exacerbations.

Fatigue was studied in COPD and age-matched control subjects. The relationship between fatigue and stable patient characteristics in COPD, and the effect of exacerbation on fatigue were evaluated.

107 COPD patients mean age 69 years (range 43-86), FEV(1) 53% (SD 21), and 30 aged-matched control subjects; Functional Assessment of Chronic Illness Therapy-Fatigue Scale, Centre for Epidemiological Studies Depression Scale.

Fatigue in COPD patients was significantly increased compared to control subjects (mean 35.3 units (SD 11.0) versus 43.2 (10.5), p=0.001). Increase in fatigue in COPD was related to reduced time spent outdoors (r=-0.43, p<0.001), increase in depression (r=-0.59, p<0.001) and annual exacerbation frequency (r=-0.27, p=0.005). Fatigue increased at exacerbation in 31/32 patients. Overall, fatigue increased by 8.3 units (5.9), p<0.001. Change in fatigue at exacerbation was related to increase in depression (r=-0.46, p=0.008). Fatigue recovered at 6 weeks following exacerbation.

The perception of fatigue increased in patients with COPD compared to age-matched control subjects, and associated with morbidity when patients were stable and at exacerbation.