Short- and long-term outcomes in critically ill patients with primary glomerular disease: a case‒control study

Glomerular diseases, encompassing primary and secondary forms, pose significant morbidity and mortality risks. Despite their impact, little is known about critically ill patients with primary glomerulopathy admitted to the intensive care unit (ICU). We conducted a case‒control study of patients with primary glomerulopathy using the Medical Information Mart for Intensive Care IV database. Demographic, clinical, and outcome data were collected. Logistic regression and mediation analysis were performed to identify predictors of hospital and long-term mortality. Among 50,920 patients, 307 with primary glomerulopathy were included. Infectious and cardiovascular-related causes were the main reasons for ICU admission, with sepsis being diagnosed in more than half of the patients during their ICU stay. The hospital mortality rate was similar to that of the control group, with a long-term mortality rate of 29.0% three years post-ICU discharge. Reduced urine output and serum albumin were identified as independent predictors of hospital mortality, while serum albumin and the Charlson comorbidity index were significantly associated with long-term mortality. Notably, although acute kidney injury was frequent, it was not significantly associated with mortality. Additionally, reduced urine output mediates nearly 25% of the association between serum albumin and hospital mortality. Critically ill patients with primary glomerulopathy exhibit unique characteristics and outcomes. Although hospital mortality was comparable to that of the control group, long-term mortality remained high. The serum albumin concentration and Charlson Comorbidity Index score emerged as robust predictors of long-term mortality, highlighting the importance of comprehensive risk assessment in this population. The lack of an association between acute kidney injury and mortality suggests the need for further research to understand the complex interplay of factors influencing outcomes in this patient population.