title: Fatigue in COPD and the impact of respiratory symptoms and heart disease--a population-based study.
abstract: BACKGROUND
  Fatigue is reported in COPD and in heart disease; however, there are hardly any population based data on the relationship between these conditions.
  
  
  OBJECTIVE
  To describe fatigue in relation to COPD by disease severity and to evaluate the impact of respiratory symptoms and heart disease.
  
  
  METHODS
  Data were collected in 2007 from the OLIN COPD study; 564 subjects with COPD (FEV1/FVC < 0.70) and a distribution of disease severity representative for the general population, and 786 subjects without COPD. The Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue scale was used to assess fatigue (0-52); lower scores represent worse fatigue.
  
  
  RESULTS
  Median FACIT-F score was 44.0 in COPD defined by merely spirometric criteria and 42.0 in COPD also reporting respiratory symptoms, significantly lower compared to 46.0 in non-COPD (p = 0.006 and p < 0.001), and decreased by disease severity. The score was lower in COPD stage ≥ II and in COPD with respiratory symptoms already from stage I when compared to non-COPD. Subjects with heart disease reported lower scores than those without heart disease in COPD by all stages and in non-COPD. COPD with respiratory symptoms stage ≥II remained a significant risk factor for clinically significant fatigue also when adjusted for gender, age, heart disease and smoking habits (stage II OR 1.65, CI 1.17-2.31 and stage III-IV OR 2.66, CI 1.11-6.36).
  
  
  CONCLUSIONS
  Fatigue is common in COPD, and is affected by respiratory symptoms and concomitant heart disease. In COPD with respiratory symptoms stage ≥ II, there is an increased risk for clinically significant fatigue.
authors.affiliation: Department of Health Science, Division of Nursing, Luleå University of Technology, Luleå, Sweden.
authors.forename: Caroline
authors.initials: C
authors.lastname: Stridsman
authors.forename: Hana
authors.initials: H
authors.lastname: Müllerova
authors.forename: Lisa
authors.initials: L
authors.lastname: Skär
authors.forename: Anne
authors.initials: A
authors.lastname: Lindberg
mesh_terms: D000368:Aged; D003371:Cough / Q000150:complications; D004417:Dyspnea / Q000150:complications; D005221:Fatigue / Q000209:etiology*; D005260:Female; D005541:Forced Expiratory Volume; D006331:Heart Diseases / Q000150:complications*; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology; D012135:Respiratory Sounds; D012720:Severity of Illness Index; D013147:Spirometry