title: Time course of arthralgia among women initiating aromatase inhibitor therapy and a postmenopausal comparison group in a prospective cohort.
abstract: BACKGROUND
  More than 80,000 postmenopausal breast cancer patients in the United States each year are estimated to begin a 5-year course of aromatase inhibitors (AIs) to prevent recurrence. AI-related arthralgia (joint pain and/or stiffness) may contribute to nonadherence, but longitudinal data are needed on arthralgia risk factors, trajectories, and background in postmenopause. This study sought to describe 1-year arthralgia trajectories and baseline covariates among patients with AI and a postmenopausal comparison group.
  
  
  METHODS
  Patients initiating AIs (n = 91) were surveyed at the time of AI initiation and at 6 repeated assessments over 1 year. A comparison group of postmenopausal women without breast cancer (n = 177) completed concomitantly timed surveys. Numeric rating scales (0-10) were used to measure pain in 8 joint pair groups (bilateral fingers, wrists, elbows, shoulders, hips, knees, ankles, and toes). Poisson regression models were used to analyze arthralgia trajectories and risk factors.
  
  
  RESULTS
  By week 6, the AI-initiating group had more severe arthralgia than did the comparison group (ratio of means = 1.8, 95% confidence interval = 1.24-2.7, P = .002), adjusting for baseline characteristics. Arthralgia then worsened further over 1 year in the AI group. Menopausal symptom severity and existing joint-related comorbidity at baseline among women initiating AI were associated with more severe arthralgia over time.
  
  
  CONCLUSIONS
  Patients initiating AI should be told about the timing of arthralgia over the first year of therapy, and advised that it does not appear to resolve over the course of a year. Menopausal symptoms and joint-related comorbidity at AI initiation can help identify patients at risk for developing AI-related arthralgia.
authors.affiliation: Vanderbilt University Medical Center, Nashville, Tennessee 37203-1738, USA. liana.castel@vanderbilt.edu
authors.forename: Liana D
authors.initials: LD
authors.lastname: Castel
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Hartmann
authors.forename: Ingrid A
authors.initials: IA
authors.lastname: Mayer
authors.forename: Benjamin R
authors.initials: BR
authors.lastname: Saville
authors.forename: JoAnn
authors.initials: J
authors.lastname: Alvarez
authors.forename: Chad S
authors.initials: CS
authors.lastname: Boomershine
authors.forename: Vandana G
authors.initials: VG
authors.lastname: Abramson
authors.forename: A Bapsi
authors.initials: AB
authors.lastname: Chakravarthy
authors.forename: Debra L
authors.initials: DL
authors.lastname: Friedman
authors.forename: David F
authors.initials: DF
authors.lastname: Cella
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000009:adverse effects*; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D018771:Arthralgia / Q000139:chemically induced*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D016012:Poisson Distribution; D017698:Postmenopause; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors