Admission CRP to albumin ratio is associated with 3-month post-discharge mortality in patients with sepsis presenting to the emergency department: a single-center study from Iran

Background Sepsis is characterized by a dysregulated host inflammatory response to infection, leading to organ dysfunction and high mortality. Because systemic inflammation increases C-reactive protein (CRP) and suppresses albumin synthesis, the CRP/albumin (CRP/Alb) ratio has emerged as a potential prognostic marker. However, evidence from emergency settings, particularly in low- and middle-income countries such as Iran, remains limited. This study evaluated the prognostic value of the admission CRP/Alb ratio for in-hospital mortality, 1-month post-discharge mortality, and mortality between 1 and 3 months after discharge in patients with sepsis. Methods In this prospective study, 200 septic patients who presented to the Emergency Department (ED) of Al-Zahra Hospital in Isfahan, Iran, during a course of one year were enrolled. CRP and albumin levels were measured at ED admission to calculate the admission CRP/Alb ratio. Vital status was assessed during hospitalization and at 1 and 3 months after hospital discharge. Univariable and multivariable logistic regression analyses were used to assess the association between the admission CRP/Alb ratio and mortality. Receiver operating characteristic (ROC) analysis was performed to evaluate its discriminatory ability and determine the optimal cut-off value. Results In-hospital mortality was 67.0% (134/200). Among patients discharged alive, 1-month post-discharge mortality was 13.6% (9/66). Among patients alive at the 1-month post-discharge follow-up, mortality between 1 and 3 months after discharge was 21.1% (12/57). The admission CRP/Alb ratio was significantly higher in patients who died between 1 and 3 months after discharge than in survivors ( p = 0.016). The CRP/Alb ratio remained associated with later post-discharge mortality after adjustment for potential confounders (adjusted OR = 1.05; 95% CI: 1.01–1.10; p = 0.014). ROC analysis showed moderate prognostic value, with an area under the curve of 0.72 (95% CI: 0.551–0.899; p = 0.017). The optimal cut-off value was 24.68, yielding 83% sensitivity and 60% specificity. Conclusions The admission CRP/Alb ratio measured at ED presentation may serve as a simple, accessible, and potentially useful biochemical marker for identifying septic patients at increased risk of later post-discharge mortality. However, given the limited number of post-discharge events, these findings should be interpreted cautiously and validated in larger multicenter cohorts.