Abstract
Background and Objectives: Immunodeficiency associated with aging comorbidities increases the vulnerability of geriatric patients to sepsis. Early recognition and management of sepsis are essential in this population. This study evaluated the relationships between RDW, MPV, and MPV/PLT ratios and mortality in geriatric sepsis patients. Materials and Methods: This retrospective study was conducted between 2020 and 2024 in the Intensive Care Unit of the Department of Anesthesiology and Reanimation at a university hospital. Patients aged ≥ 65 years with a SOFA score of ≥2 were included. Demographic data (sex, age, height, weight, and BMI), hemogram parameters (RDW, MPV, and PLT), blood gas, and biochemical values were analyzed. Furthermore, their comorbidities; site of infection; ICU length of stay; vital signs; and SOFA, APACHE II, and SAPS II scores, recorded within the first 24 h following ICU admission, were evaluated. Statistical analysis was performed using the chi-square test, Student's t-test, the Mann-Whitney U test, the Monte Carlo exact test, and ROC analysis. A p-value of <0.05 was considered statistically significant. Results: A total of 247 patients were included, with 46.2% (n = 114) classified as non-survivors during the 28-day follow-up period. Among them, 64.9% (n = 74) were male, with a mean age of 78.22 ± 8.53 years. Significant differences were also found in SOFA, APACHE-II, and SAPS-II scores between non-survivors and survivors (SOFA: 7.64 ± 3.16 vs. 6.78 ± 2.78, p = 0.023; APACHE-II: 21.31 ± 6.36 vs. 19.27 ± 5.88, p = 0.009; SAPS-II: 53.15 ± 16.04 vs. 46.93 ± 14.64, p = 0.002). On days 1, 3, and 5, the MPV/PLT ratio demonstrated a statistically significant predictive value for 28-day mortality. The optimal cut-off values were >0.03 on day 1 (AUC: 0.580, 95% CI: 0.516-0.642, sensitivity: 72.81%, specificity: 65.91%, p = 0.027), >0.04 on day 3 (AUC: 0.602, 95% CI: 0.538-0.663, sensitivity: 60.53%, specificity: 60.61%, p = 0.005), and >0.04 on day 5 (AUC: 0.618, 95% CI: 0.554-0.790, sensitivity: 66.14%, specificity: 62.88%, p = 0.001). Conclusions: The MPV and MPV/PLT ratios demonstrated statistically significant but limited predictive value for 28-day mortality in geriatric patients with sepsis. In contrast, the limited prognostic value of RDW may be related to variability in the inflammatory response and other underlying conditions. The correlations found between SOFA, APACHE II, and SAPS II scores highlight their importance in mortality risk prediction.