Assessing frailty in patients with relapsed/refractory multiple myeloma: A comparison between the patient-reported frailty phenotype and the International Myeloma Working Group frailty index

Introduction: The International Myeloma Working Group Frailty Index (IMWG FI) is one of the most used frailty assessment tools in patients with multiple myeloma (MM). A patient-centered frailty tool based on patient-reported outcomes (PROs) has been recently proposed for patients with relapsed/refractory MM (RRMM): the Patient-Reported Frailty Phenotype (PRFP). This cross-sectional analysis aimed to replicate the PRFP within a real-world setting and to describe health-related quality of life (HRQoL) profiles based on this new patient-centered frailty classification. Materials and Methods: This analysis was based on baseline data from a multi-center prospective observational study that included adult patients with RRMM. Frailty was assessed using the IMWG FI, and HRQoL was evaluated with the EORTC QLQ-C30 and its myeloma module (QLQ-MY20). For this analysis, the PRFP was also calculated, and Cohen's kappa was computed to examine the agreement between the two frailty assessment approaches. Descriptive statistics were used to investigate the HRQoL profiles of patients classified as frail, pre-frail, and fit. Results: Five hundred eleven patients were enrolled. The median age was 69.8 years, and 44 % were female. According to IMWG FI and PRFP, 24.5 % and 25.1 % of patients were classified as frail, with a weighted Cohen's kappa of 0.27, indicating fair agreement. Frail patients, as classified by the PRFP, reported higher treatment side effects, disease symptoms, and worse future perspectives and body image compared to pre-frail and fit patients. Discussion: Current findings suggest that the PRFP may be a valuable tool to assess frailty in patients with RRMM. However, further prospective studies are needed to better understand the value of PROs in a more accurate assessment of frailty in the RRMM setting. Trial registration: ClinicalTrials.gov: NCT03190525