title: Changes over time in occurrence, severity, and distress of common symptoms during and after radiation therapy for breast cancer.
abstract: BACKGROUND
  Little is known about changes over time in multiple dimensions of the symptom experience in patients with breast cancer undergoing radiation therapy (RT).
  
  
  OBJECTIVE
  This study evaluated for changes in and predictors of occurrence, severity, and distress of six common symptoms (lack of energy, worrying, difficulty sleeping, feeling drowsy, sweats, and pain) during RT for breast cancer.
  
  
  METHODS
  Patients (n = 188) completed the Memorial Symptom Assessment Scale before, during, and after the completion of RT, over a six-month period. Changes in symptom occurrence were evaluated using multilevel logistic regression analysis. Changes in severity and distress scores were evaluated using multilevel proportional odds ordinal logistic regression. The impact of five demographic and clinical characteristics (age, functional status, comorbidities, axillary lymph node dissection, and previous chemotherapy) was evaluated in these analyses.
  
  
  RESULTS
  The trajectories for occurrence, severity, and distress for the six symptoms followed similar patterns. For three of the six symptoms (lack of energy, feeling drowsy, and worrying), all three dimensions changed over time. For the other three symptoms (difficulty sleeping, sweats, and pain), no changes over time occurred for any of the symptom dimensions. The overall effect of the five covariates was to increase symptom burden across all three dimensions.
  
  
  CONCLUSIONS
  Findings from this study provide a more complete picture of the symptom experience of women who undergo RT for breast cancer. These findings can be used to identify patients at higher risk for more severe symptoms before, during, and after RT.
authors.affiliation: Centre for Shared Decision Making and Collaborative Research, Oslo University Hospital, Rikshospitalet, Oslo, Norway. kristin.hofso@rr-research.no
authors.forename: Kristin
authors.initials: K
authors.lastname: Hofsø
authors.forename: Tone
authors.initials: T
authors.lastname: Rustøen
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Cooper
authors.forename: Kristin
authors.initials: K
authors.lastname: Bjordal
authors.forename: Christine
authors.initials: C
authors.lastname: Miaskowski
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000523:psychology / Q000532:radiotherapy*; D015984:Causality; D015897:Comorbidity; D018450:Disease Progression; D005221:Fatigue / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D015995:Prevalence; D011788:Quality of Life / Q000523:psychology; D020266:Radiotherapy, Conformal / Q000523:psychology / Q000706:statistics & numerical data*; D018570:Risk Assessment; D012720:Severity of Illness Index; D012893:Sleep Wake Disorders / Q000453:epidemiology* / Q000523:psychology; D013315:Stress, Psychological / Q000453:epidemiology* / Q000523:psychology; D016896:Treatment Outcome