Renal impairment is reported in 20%-50% of patients with newly diagnosed multiple myeloma and is known as a poor prognostic factor. Although several studies have demonstrated that treatment with novel antimyeloma agents improves renal impairment and myeloma itself, the time-dependent clinical course of recovery of renal function has not been extensively studied. We retrospectively collected the data of characteristics and outcomes in consecutive unselected patients diagnosed with and treated for symptomatic multiple myeloma between January 2015 and December 2022, and extracted and analyzed the cases with renal impairment. Among 234 patients with multiple myeloma, 67 (28.6%) had renal impairment (estimated glomerular filtration rate (eGFR) <
60 ml/min/1.73m