Association Between Objective And Patient Reported Changes In Physical Function Following An Exercise Oncology Program

PURPOSE: Measuring physical function in individuals treated for cancer is essential to identify functional deficits, provide prognostic information, and monitor supportive care effectiveness. The predominant method for assessing physical function is through patient report, capturing the perceived level of function. However, there is a lack of understanding in the relationship between patient report and objective physical function. As such, the purpose of this study was to determine the association between changes in objective and patient reported physical function following an exercise oncology program. METHODS: Participants were recruited from local hospitals in the Midlands region of South Carolina. All participants completed supervised exercise sessions 2 days/week for 8 weeks. Sessions consisted of 6-8 resistance exercises targeting each of the major muscle groups followed by 15-20 minutes of moderate intensity aerobic activity. Prior to and following the exercise program, objective physical function was assessed using the 2-minute step test (2MST), 30-second sit to stand (30STS), timed arm curl (TAC), and timed up and go (TUG). Patient reported physical function was assessed using the PROMIS-Physical Function Computerized Adaptive Test. Association between changes in objective and patient reported physical function was assessed using concordance correlation coefficient (CCC) testing. RESULTS: 45 individuals treated for cancer (female: 95%, age: 62 ± 11, BMI: 30 ± 6, time since diagnosis (moths): 58 ± 69) completed assessments. Objective and patient reported physical function improved significantly following the intervention (p < 0.01). Changes in objective physical function displayed low association with changes in patient reported physical function (2MST: CCC = <0.1, 30STS: CCC = 0.2, TAC: CCC = < 0.1, and TUG: CCC = < 0.1). CONCLUSIONS: These findings suggest that there is a lack of agreement between changes in objectively measured and patient reported physical function. The discordance between objective and patient reported function indicates that unique information may be captured by each approach and that an optimal assessment of physical function should include both.