Systematic review of frailty, functional status & comorbidities in older adults with multiple myeloma undergoing high dose therapy & autologous stem cell transplant.

[INTRODUCTION] Improvements in supportive care strategies and growing evidence for benefit have led to increased use of autologous stem cell transplant (ASCT) in older patients with multiple myeloma (MM). However, the lack of standardized criteria for transplant eligibility often leaves the decision to the physician's clinical judgment. The roles of frailty/geriatric assessment tools, functional status, and comorbidity in selecting candidates and predicting transplant outcomes in older patients with MM remain uncertain. The purpose of this systematic review was to examine the measures of frailty, functional status, and comorbidity reported for older patients with MM who underwent ASCT and to evaluate their association with outcomes.

[MATERIALS AND METHODS] On April 11, 2024, MEDLINE, EMBASE, and the Cochrane Library were searched for articles that included older adults (>60 years) with MM addressing the use of ASCT or ASCT eligibility/ineligibility. We included retrospective and prospective studies that included (1) at least one measure of functional status and/or comorbidities and (2) at least one transplant-related outcome (response rate, transplant-related mortality).

[RESULTS] Twenty-five studies were included, four prospective and 21 retrospective. Of these, four studies utilized the International Myeloma Working Group (IMWG) frailty index, with some including frail patients. In one study utilizing a comprehensive geriatric assessment, >50 % of older adults who were considered transplant-eligible reported dependence on ≥1 Instrumental Activities of Daily Living (IADL), severe limitations in vigorous activities, and/or self-reported weight loss. Eighteen studies reported a measure of functional status, most commonly Eastern Cooperative Oncology Group Performance Status; 19 studies reported a comorbidity measure, most commonly Hematopoietic Cell Transplantation-Comorbidity Index (HCT-CI). The comorbidity scores were generally low in patients who underwent ASCT (<3). The 100-day treatment-related mortality ranged from 0 % to 6 %, with overall response rates were generally high across studies.

[DISCUSSION] There is wide variability in the tools used to assess characteristics of older adults who underwent ASCT across studies. The optimal tool for selecting older ASCT candidates remains undefined, but it is likely that no single measure can adequately capture overall health status. Prospective studies incorporating a multidimensional assessment are necessary to better define transplant eligibility in this population.