Geriatric nutritional risk index predicted survival time in multiple myeloma

<h2>Summary</h2><h3>Introduction</h3> Geriatric nutritional risk index (GNRI), an indicator of nutritional status, has been shown to predict overall survival (OS) in patients with hematological malignancies. However, GNRI has never been investigated in myeloma patients. This retrospective study aimed to investigate the clinical significance of GNRI in myeloma patients. <h3>Materials and Methods</h3> We reviewed the medical records of patients with newly diagnosed multiple myeloma, who had received proteasome inhibitor and/or immunomodulatory drug as initial chemotherapy from 2009 to 2022, with follow-up until December 2023. GNRI is calculated as [(14.89 × serum albumin level) + (41.7 × current body weight/ideal body weight)]. Based on previous reports, the GNRI cut-off for high-risk patients is 92. <h3>Results</h3> Three hundred and fifty-seven patients were included in this study. The median age was 71 years. The median and mean values of GNRI were 93.2 and 92.4 (±13.8), respectively. Using receiver operator characteristics (ROC) curves, a cutoff of 91.4 yielded the highest area under the curve (AUC). The proportion of patients classified as high GNRI risk was 46.8 %. In a median followed-up time of 37.8 months, OS in the high GNRI risk group was significantly shorter than that in the low GNRI risk group (3 year-OS: 66.7 % and 83.1 %; <i>P</i> > 0.001). In multivariate analysis, high GNRI risk was independently associated with poorer OS (HR 1.716, <i>P</i> = 0.016), whereas PS and simplified frailty score were not. The GNRI risk was improved during treatment overtime; the frequencies of GNRI risk at 3, 6, and 12 months after treatment was initiated was 40.0 %, 32.3 %, and 29.9 %, respectively. The GNRI risk assessed at 12 months predicted subsequent OS more accurately than the baseline GNRI, as demonstrated by ROC analysis (AUC, 0.690 <i>vs</i>. 0.582; <i>P</i> = 0.009). Patients whose GNRI improved from high risk at diagnosis to low risk at 12 months had OS comparable with those with low risk at diagnosis, suggesting that improved GNRI risk predicted good prognosis. <h3>Conclusion</h3> High GNRI risk at diagnosis predicted short OS in myeloma patients. The GNRI risk changed overtime during treatment, and a dynamic GNRI model predicted OS in myeloma patients.