In the recent years, multiple myeloma (MM) has been associated with long-term survival. Life-threatening complications may occur in those patients leading to high risk of ICU admission. Within the same period, survival of critically ill patients with malignancy improved. The aim of this study was to evaluate severity and outcome in patients with MM admitted to ICU within the last 16 years.

In this monocentric retrospective study, patients with MM admitted to ICU within two periods (2007-2015) and (2016-2023) around major therapeutic changes, were included. Patients from two periods were compared in terms of short and long terms outcomes. In the recent period, factors associated with mortality were assessed by multivariate analysis.

During the first period (2007-2015), 199 patients were included and compared to 229 patients admitted within the second period (2016-2023). Median delay from MM diagnosis to ICU was 25.9 (2.2-70.6) months and 82 (19.2%) patients were newly diagnosed patients. MM classified as high risk concerned 119 (52%) or Stade III Salmon-Durie for 142 (71.4 %) patients. SOFA score on Day 1 was 5 (2-7). During ICU stay, 115 (26.9%) patients needed invasive mechanical ventilation, 105 (24.5%) patients received vasopressors and 97 (22.7%) had renal replacement therapy. Median length of ICU stay was 3 (2-6) days. Reason for ICU admission was different between the two periods: Shock was more frequent in the second period (29.7% vs 13.7%) whereas acute respiratory failure was more frequent in the first period (35.2% vs 46.7%) (p < 0.001). ICU and one-year mortality rates were respectively 12.1% (n = 50) and 40.6% (n = 170). Mortality rates, adjusted on age, comorbidities, more than 2 lines treatment, time between hospital and ICU admission >1 day, kidney amyloidosis, SOFA score at ICU admission and reason for ICU admission, were lower in the recent period compared to the first period (0.68 (0.49-0.95), p = 0.02).

Survival in MM patients admitted to ICU improved in the recent years. Particularly, patients who were not previously heavily treated had better outcome and should be admitted to ICU.