Physical function in older adults receiving treatment: Correlates and predictors

Older adults with cancer often prioritize functional health over quantity of life. Understanding factors that influence functional health in older adults with cancer can help identify at-risk individuals as well as tailoring variables for the development of tailored behavioral interventions to improve goal-concordant cancer care and optimize quality of life. The purpose of this study was to (1) characterize physical function over time in older adults (aged 65+) receiving systemic cancer therapy, (2) identify demographic, clinical, and symptom correlates associated with physical function over time, and (3) determine the impact of baseline symptoms and frailty on physical function trajectories over time.

Data for this secondary analysis were obtained from a longitudinal, cohort, IRB-approved study in 213 older adults (aged 65+) with mixed cancer diagnoses receiving systemic cancer therapy. Data were obtained from participant medical records, self-administered cancer-specific geriatric assessment, self-reported physical function (PROMIS Physical Function-Short Form and Karnofksy Performance Status), and performance-based physical function (Timed Up and Go). Participants were followed for a six-month period, with assessments repeated at every clinical visit. Correlations were used to assess relationships between variables at baseline, and between baseline variables and physical functioning at later time points. Longitudinal linear mixed models, or hierarchical linear models, using maximum likelihood estimation were performed to assess changes in physical functioning over time, as well as predictors/moderators of change.

Age, fatigue, and frailty were associated with worse self-reported physical functioning over time. Targeted treatments were associated with improvement in self-reported physical function over time. No significant moderators were identified for performance-based physical function over time. Baseline fatigue, pain, and frailty status were all significant predictors of change in self-reported physical function over time. Only frailty status predicted change in Timed Up and Go scores over time.

We identified sociodemographic, clinical, and symptom variables that contribute to physical function over time in older adults receiving systemic therapy. These findings highlight the importance of tailoring education, conducting symptom screenings and geriatric assessments at regular clinical intervals, and early intervention to optimize physical function and quality of life for older adults with cancer.