Abstract
PURPOSE: Breast cancer (BC) survivors report declines in health-related quality of life (HRQoL), including worsening physical function and fatigue levels. It is uncertain if these changes are associated with muscle quality. This study estimated changes in muscle quality and HRQoL in BC participants over 24 months of treatment and tested associations with muscle quality and HRQoL. METHODS: Women (n = 149, 50.3 ± 10.7 years) diagnosed with stage I-III BC (PREVENT-WF-98213) reported HRQoL via Patient-Reported Outcomes Measurement Information System (PROMIS) surveys at baseline prior to cancer treatment and at 6-months and 24-months follow up from treatment initiation. Paraspinal intermuscular fat (IMF) and skeletal muscle (SM) were determined by magnetic resonance imaging, and the IMF:SM ratio was calculated to estimate muscle quality. Analyses included linear mixed-effects models adjusting for study group (placebo/statin), age, race, and body mass index. RESULTS: HRQoL declined from baseline to 6-months but returned to baseline levels by 24-months. Muscle quality worsened from baseline through 24-months manifested by an increase in IMF. Individuals with better muscle quality at baseline reported declines in HRQoL from baseline to 6-months (mean difference [MD] = - 0.12 ± 0.03, p < 0.001), whereas participants with poor baseline muscle quality did not (MD = - 0.06 ± 0.003, p = 0.14). An increase in IMF:SM over 24-months trended towards worse physical function (- 8.76 ± 5.79, p = 0.132). CONCLUSION: Muscle quality worsened over 24-months and trended toward worse physical function at 24-months follow-up. From initial declines during treatment, participants reported recovered HRQoL by 24-months. Further work in a larger cohort is needed to confirm associations with muscle quality and physical function.