title: Chemotherapy interruptions in relation to symptom severity in advanced breast cancer.
abstract: OBJECTIVE
  Interruptions in medical treatment such as dose delays, reductions, or stoppages can lead to suboptimal treatment of cancer. Knowing how and for whom symptom severity and symptom interference with activities of daily living (ADL) are associated with treatment interruptions can guide behavioral interventions for supportive care. The purpose of this analysis is to inform research and clinical practice by bringing attention to specific patient symptoms that may hinder dose completion.
  
  
  METHODS
  A secondary analysis of data collected in a randomized clinical trial (RCT) of reflexology for symptom management was performed. The trial enrolled women with advanced breast cancer undergoing treatment (N = 385). Outcome data were collected at baseline, weeks 5 and 11 using valid and reliable measures. Medical records provided data on treatment interruptions and metastasis. The association between alterations in medical treatment during the study period with symptom severity, symptom interference with ADLs, and metastatic status were tested using generalized estimating equation (GEE) models.
  
  
  RESULTS
  The relationship between dose delays and dose reductions and symptom severity was differential according to metastatic status, with the higher strength of association among women with distant metastasis compared to those with loco-regional disease (p = 0.02). The interaction of symptom interference and metastatic status was also significantly related to dose delays and reductions (p = 0.04). Severity of pain was a stronger predictor of dose delays or reductions among patients with distant metastasis compared to those with loco-regional disease (p < 0.01).
  
  
  CONCLUSIONS
  The analysis highlights the importance of understanding symptom outcomes that impact research, practice, and treatment decisions.
authors: College of Nursing, Michigan State University, 1355 Bogue Street, Room C345, East Lansing, MI, 48824, USA. gwyatt@msu.edu.
authors: Gwen
authors: G
authors: Wyatt
authors: Department of Statistics and Probability, Michigan State University, 619 Red Cedar Road, Room C423, East Lansing, MI, 48824, USA.
authors: Alla
authors: A
authors: Sikorskii
authors: Department of Statistics and Probability, Michigan State University, 619 Red Cedar Road, Room C423, East Lansing, MI, 48824, USA.
authors: Irena
authors: I
authors: Tesnjak
authors: Department of Medical Social Sciences, Feinberg School of Medicine, Northwestern University, 2205 Tech Drive, Hogan Building (Suite 2-120), Evanston, IL, 60208, USA.
authors: David
authors: D
authors: Victorson
authors: Clinical Trials, Sparrow Health System, 1215 E. Michigan Ave., Lansing, MI, 48912, USA.
authors: Gordan
authors: G
authors: Srkalovic
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000628:therapy*; D005260:Female; D006801:Humans; D008405:Massage; D008875:Middle Aged; D010146:Pain / Q000503:physiopathology; D010147:Pain Measurement; D016079:Refusal to Treat; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents
keywords: Breast cancer; Supportive care; Symptom management; Treatment interruptions