Clinical and sociodemographic characteristics associated with health-related quality of life among older breast cancer survivors

BACKGROUND: Health-related quality of life (HRQoL) measures may help incorporate patient preferences and deliver individualized care for older breast cancer survivors. However, few studies have used clinically meaningful thresholds to evaluate the various characteristics associated with HRQoL in older women. OBJECTIVES: To examine sociodemographic and clinical characteristics associated with HRQoL and minimal clinically important differences (MCIDs) among female breast cancer survivors aged ⩾65 years. DESIGN: A cross-sectional study. METHODS: We used 2006-2015 Surveillance, Epidemiology, and End Results data linked to the Medicare Health Outcomes Survey (SEER-MHOS) for U.S. women aged ⩾65 years diagnosed with stages I-III invasive breast cancer. Descriptive statistics were used to summarize data. Generalized linear regression models were fitted to identify characteristics associated with the HRQoL physical component summary (PCS) and mental component summary (MCS) scores from the Veterans RAND 12-Item Health Survey scale. Missing values were imputed using chained equations. A threshold of two points was used to identify clinically meaningful between-group differences. RESULTS: The median age at diagnosis was 72 years (interquartile range: 68-76) among 3218 breast cancer survivors. Obesity (mean difference (MD): -2.42; 95% confidence interval (CI): -3.34, -1.49), older age (⩾80 years; MD: -2.05; 95% CI: -3.15, -0.96), difficulty with ⩾1 activities of daily living (ADL; MD: -11.70; 95% CI: -12.42, -10.99), and cardiovascular (MD: -2.27; 95% CI: -3.02, -1.53) and musculoskeletal disease (MD: -3.88; 95% CI: -4.67, -3.09) were associated with clinically meaningful lower PCS scores. Less than high school education (MD: -3.43; 95% CI: -4.53, -2.33), annual household income ≤$19,999 (MD: -4.08; 95% CI: -6.00, -2.16) and $20,000-$39,999 (MD: -2.71; 95% CI: -4.63, -0.79), no surgery (MD: -3.03; 95% CI: -5.33, -0.72), difficulty with ≥1 ADL (MD: -6.71; 95% CI: -7.52, -5.89), and obesity (MD:2.06; 95% CI: 1.00, 3.12) were associated with MCIDs in MCS scores. CONCLUSION: Clinically meaningful differences in HRQoL were observed across sociodemographic and clinical characteristics in older female breast cancer survivors. These results may help identify women in need of interventions to improve HRQoL post-diagnosis.