Onset and risk factors for aromatase inhibitor-related arthralgia in breast cancer survivors.

Abstract

#1120 Purpose: Arthralgia is a common clinical phenomenon seen in postmenopausal women receiving aromatase inhibitors (AI). This study aims to evaluate the perceived onset, prevalence, and risk factors for AI-related arthralgia.
 Patients and Methods: We performed a cross-sectional analysis of a cohort of postmenopausal women with stage I-III breast cancer receiving adjuvant AI therapy at an outpatient breast oncology clinic at a large university hospital. Patient-reported symptoms and attribution of AI as a cause of arthralgia were main outcomes. Multivariate logistic regression analyses were performed to assess risk factor(s).
 Results: 300 patients have been enrolled, with a mean age of 61 +/- 10 years, 84% White, and 38(13%) Black. A total of 173 (58%) reported AI-related arhtralgia during the course of AI treatment and 139 (47%) attributed AI as a cause of their current arthralgia. While 103 (34%) reported having “arthritis” prior to AI initiation, 13% reported onset of symptoms within 1 month of medication initiation, 42% between 1-3 months, 27% between 3-6 months, 12% between 6-12 months, and 20% after 12 months. In a multivariate logistic regression model, time since last menstrual period (LMP) was the only significant predictor of reporting AI-related arthralgia; age, race, employment status, chemotherapy, and weight gain since breast cancer were not associated with the clinical syndrome. Controlling for these covariates, those who had LMP within 5 years had the highest probability of reporting AI-related arthralgia (73%), while those with LMP beyond 10 years had the lowest (35%), p=0.017. Prior arthritis was unrelated to AI-related arthralgia either in univariate or multivariate analyses.
 Conclusions: AI-related arthralgia is common and appears to be inversely related to the length of time since cessation of menstrual function. These findings suggest that estrogen withdrawal may compound these symptoms and may play a role in the mechanism of this disorder. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1120.