Pre-treatment neutrophil to lymphocyte ratio as a biomarker of frailty and predictor of survival among older adults with multiple myeloma

Neutrophil to Lymphocyte Ratio (NLR) combines a marker of inflammation and reduced cell turnover to reflect age related alterations in the immune system. Whether NLR can serve as a biomarker of frailty and predict survival among older adults with Multiple Myeloma (MM) is unknown.We used an electronic health record-derived database to identify older adults (age ≥ 60y) with incident MM diagnosed between 1/2011 and 2/2020, with known pre-treatment absolute neutrophil and lymphocyte count up to 90 days before the start of therapy. The calculated NLR values were stratified into quartiles (Q1-Q4). We constructed a previously validated, simplified frailty index combining age, comorbidity and ECOG performance status. We measured the association between NLR quartiles and this frailty index using a logistic regression, adjusted for age, sex and race/ethnicity. We used Kaplan Meier methods and multivariable Cox regression to assess the impact of NLR on overall survival adjusting for potential confounders.We identified 1729 older adults with newly diagnosed MM, at a median age of 73y (IQR: 67-78y). The median NLR was 2.13 (IQR: 1.44 to 3.31). Of the 1135 evaluable patients, 55% met criteria for frailty. Multivariable analysis revealed a 2.1-fold higher odds of frailty (95%CI = 1.42-3.10, p < 0.001) for patients in the NLR Q4 group vs. NLR Q1 group. In a multivariable analysis, adjusting for age, sex, race/ethnicity, M-protein type, stage, high risk cytogenetics, baseline creatinine, LDH and type of first line therapy, patients in NLR Q4 group had a 1.51 times increased hazards of death (95%CI = 1.15-1.98, p 0.002) when compared to those in NLR Q1 group.NLR, a readily available laboratory biomarker, is associated with frailty measured using a simplified frailty index as well as inferior overall survival among older adults with MM. Future studies should explore its value as a screening tool to identify frail older adults with MM.