Impact of Kidney Impairment Recovery on Survival of Patients with Newly Diagnosed Multiple Myeloma

Background: It has recently been suggested that recovery of Renal Impairment(RI) after treatment(AT) of patients(pts) with multiple myeloma (MM) is a better predictor of overall survival(OS) than RI at diagnosis(AD). Our aim is to assess the impact of RI recovery on the OS of pts with newly diagnosed(NDMM) Methods: We screened adult pts with NDMM admitted for treatment at the Sao Paulo State Cancer Institute between January 2009 and September 2018. Estimated glomerular filtration rate(eGFR) was determined by the 2021 CKD-EPI creatinine(Cr) equation in ml/min/1.73m2. RI was defined as eGFR<40 or serum Cr>2.0mg/dL. Chronic Kidney Disease (CKD) criteria was eGFR<60ml/min/1.73m2, considering Cr in the previous three months before MM diagnosis. Acute Kidney Injury (AKI) was stratified according to the KDIGO criteria. Patients were classified into 3 groups: (1)no RI at diagnosis, (2)RI AD with recovery AT, (3)RI AD without recovery AT Results: We enrolled 429 pts. Median age was 61.7(54.1–69.5)y, 58.1% male. Median Charlson comorbidity index was 4.0(3.0–5.0). International staging system III was found in 37.9%. Novel agents(bortezomib or thalidomide) were used in 70.8% pts. eGFR AD and AT were 70.9(40.7–98.7) and 93.2(62.7-104.1)ml/min/1.73m2, respectively. AD, CKD, RI, and AKI stage 3 were observed in 26.3, 24.0, and 12.1% of patients, respectively. In the adjusted Cox regression models, among kidney variables, only the lowest eGFR AT was associated with worse OS(Table). Conclusion: The lowest eGFR AT might be a better predictor of OS than RI AD in pts with NDMM - Variables p value Hazard Ratio (95% Confidence interval) Renal impairment at diagnosis 0.54 1.11 (0.79 – 1.56) eGFR at admission 0.88 1.0 (0.99 – 1.05) Acute Kidney Injury stage 3 0.46 0.67 (0.51 – 0.89) Chronic kidney disease 0.67 0.94 (0.70 – 1.26) Renal recovery groupsNo Renal impairmentRenal impairment at diagnosis, recovery after treatmentRenal impairment at diagnosis, no recovery after treatment 0.290.830.12 1.04 (0.74 – 1.45)1.62 (0.88 – 2.96) Lowest eGFR in 6 months 0.004 0.99 (0.98 – 0.99) Each model was adjusted for age, Charlson index, international staging system stage 3, body mass index categorization, and usage of novel chemotherapy agent(thalidomide or bortezomib).eGFR: estimated glomerular filtration rate