Abstract P5-17-01: Development and validation of the Penn arthralgia aging scale among breast cancer survivors on aromatase inhibitors

Abstract

Abstract Background: Aromatase inhibitors (AIs) have been shown to decrease the recurrence rate and increase the overall survival rate of hormone receptor positive breast cancer among post-menopausal women. Unfortunately, arthralgia is a frequently experienced side effect of AIs, leading some women to discontinue AIs prematurely. Qualitative investigations suggest that joint pain may cause women on AIs to feel they are aging faster than they should be. Since general perceptions of aging have been shown to predict important health outcomes, such as adherence and mortality, aging perceptions related to joint pain are worth further exploration. Objective: The purpose of this study was to develop and validate a measure that captures perceptions of aging related to joint pain. A psychometrically validated tool will advance our ability to quantify and further understand the importance of this construct. Method: We developed the eight-item Penn Arthralgia-Aging Scale (PAAS) from interviews with 67 patients on AIs. The scale was pilot-tested, and changes to items were made based on patient feedback, as well as feedback from oncologists, nurses, and physical therapists. To validate the scale, participants suffering from joint pain were selected from a larger study examining the genetic determinants of symptom distress and disease outcomes among women on AIs. Five hundred and fifty-six breast cancer survivors completed the PAAS, as well as the Hospital Anxiety and Depression Scale, the pain interference and pain intensity subscales of the Brief Pain Inventory, and a demographic questionnaire. Exploratory factor analysis using oblique rotation was conducted to examine the factor structure of the scale. Convergent validity was assessed by correlating the PAAS with joint-pain severity. To determine whether the scale provides important information beyond existing measures, we used hierarchical regressions to calculate whether it predicted incremental variance in anxiety, depression, and pain interference outcomes. Results: The resulting scale had a one-factor structure (eigenvalue = 6.21), high internal consistency (Cronbach’s alpha = 0.94), and strong convergent validity (Spearman r = .55, p < 0.01 for joint pain). Additionally, the PAAS was found to explain additional variance in anxiety (7%, p < 0.001) and depression (28%, p < 0.001) after pain severity and age were controlled. The PAAS also explained additional variance (5%, p < 0.001) in joint pain interference above and beyond the variance accounted for by anxiety, depression, joint pain severity, and age. Conclusions: These findings suggest that the PAAS is a reliable and valid tool that captures a meaningful construct of perceptions of aging attributable to arthralgia. With further research, the PAAS may advance our understanding of breast cancer survivors’ emotional, behavioral, and clinical outcomes. Citation Format: Moriah J Brier, Dianne L Chambless, Laura Lee, Angela DeMichele, Jun J Mao. Development and validation of the Penn arthralgia aging scale among breast cancer survivors on aromatase inhibitors [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-17-01.