title: Impact of fatigue on overall quality of life in lung and breast cancer patients selected for high-dose radiotherapy.
abstract: BACKGROUND
  Although studies show that cancer patients consider fatigue as an important problem, few, if any, studies have quantified the impact of fatigue on overall quality of life (QoL) in cancer patients. In the present study, we evaluated the relative impact of different QoL domains/subscales, including fatigue, on overall QoL in cancer patients preceding radiotherapy.
  
  
  METHODS
  Sixty-four patients with lung or breast cancer selected for high-dose radiotherapy on the primary tumour completed the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire. Multivariate models were fitted to define the impact of QLQ-C30 subscales, including fatigue, on overall QoL.
  
  
  RESULTS
  Of all QLQ-C30 subscales, fatigue showed by far the strongest univariate correlation with overall QoL (r = -0.76, P < 0.001); correlations for functioning subscales (r = 0.44-0.55) and symptom subscales (r = -0.31 to -0.45) were considerably lower. In multivariate analyses, adjusting for potential confounders, fatigue was the only subscale that independently contributed to overall QoL (standardized regression coefficient-0.57, P < 0.001).
  
  
  CONCLUSIONS
  Our results indicate that, of all QoL domains/subscales, fatigue is by far the predominant contributor to patient-perceived overall QoL in both lung and breast cancer patients preceding high-dose radiotherapy.
authors.affiliation: Department of Epidemiology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands. dagnelie@epid.unimaas.nl
authors.forename: P C
authors.initials: PC
authors.lastname: Dagnelie
authors.forename: M C G
authors.initials: MC
authors.lastname: Pijls-Johannesma
authors.forename: P
authors.initials: P
authors.lastname: Lambin
authors.forename: S
authors.initials: S
authors.lastname: Beijer
authors.forename: D
authors.initials: D
authors.lastname: De Ruysscher
authors.forename: G I J M
authors.initials: GI
authors.lastname: Kempen
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000532:radiotherapy*; D005221:Fatigue; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D011879:Radiotherapy Dosage; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires