Insights through the renal lens: Clinical outcomes of newly diagnosed multiple myeloma patients with and without renal impairment in a resource-limited setting.

Abstract

e19531 Background: Renal impairment (RI) is a frequent and clinically significant complication of newly diagnosed multiple myeloma (NDMM), associated with increased tumor burden, treatment limitations, and inferior survival. However, real-world data on its prognostic impact and dynamic renal recovery from resource-limited settings remain scarce. Methods: We conducted a retrospective cohort study of NDMM patients diagnosed between December 2010 and March 2023 at Aga Khan University, Pakistan. RI was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² and/or serum creatinine >2 mg/dL at diagnosis. Patients were stratified by RI status. Clinical, laboratory, treatment, and survival data were extracted. Renal recovery was defined as ≥25% improvement in eGFR at 6 months. Survival analyses were performed using Kaplan–Meier methods, and logistic regression identified predictors of disease progression. Results: Among 218 NDMM patients (median age 60 years; 66.5% male), 101 (46.3%) had RI at diagnosis. RI patients had significantly higher creatinine, β2-microglobulin, calcium, and free light chain levels, and were more frequently R-ISS stage III (p<0.001). Induction regimens were comparable between groups, with CYBORD and THAL-DEX most commonly used. Median baseline eGFR was markedly lower in RI patients (23 vs. 78 mL/min, p<0.001) and remained significantly reduced at 6 months. More than half of RI patients (53.5%) achieved ≥25% improvement in eGFR. Mean overall survival (OS) was 92 months in RI versus 111 months in non-RI patients, and mean progression-free survival (PFS) was 59 versus 104 months, respectively. Persistent eGFR <60 mL/min at 6 months independently predicted disease progression (OR 2.63, p<0.001). RI patients with ≥25% eGFR improvement had OS comparable to non-RI patients. Conclusions: Renal impairment at diagnosis is associated with higher disease burden and inferior survival in NDMM. Early renal recovery, reflected by ≥25% improvement in eGFR, mitigates this risk and is associated with outcomes comparable to patients without RI. Dynamic monitoring of eGFR provides a powerful, low-cost prognostic tool and should be integrated into routine management, particularly in resource-constrained settings.