Association between hemoglobin dynamic trajectories and 28-day mortality in elderly patients with sepsis: A retrospective cohort study using the MIMIC-IV database
Clinical Snapshot
PICO Framework
| P — Population | Elderly patients (≥65 years) with sepsis from MIMIC-IV database (n=4,961) |
| I — Intervention | Hemoglobin trajectory classification using Joint Latent Class Model |
| C — Comparator | Three hemoglobin trajectory classes: persistently low (Class 1), medium with gradual decline (Class 2), rapid decline from higher levels (Class 3) |
| O — Outcomes | 28-day mortality, survival probability |
Bottom Line
This large retrospective cohort study of 4,961 elderly sepsis patients demonstrates that hemoglobin trajectory patterns predict 28-day mortality. Patients with persistently low hemoglobin (38% increased mortality risk) or rapid hemoglobin decline (21% increased mortality risk) had significantly worse outcomes compared to those with medium levels and gradual decline. While the sophisticated trajectory modeling provides novel insights into hemoglobin dynamics in sepsis, the study lacks external validation and practical implementation guidance. The findings may inform prognostic discussions and potentially guide transfusion strategies in elderly sepsis patients, but require validation in independent cohorts before routine clinical application. The study reinforces the prognostic importance of anemia in sepsis while highlighting the value of longitudinal rather than single-point hemoglobin measurements.
Key Findings
P Value: Class 1: p < 0.001; Class 3: p = 0.020
Effect Size: Class 1 (persistently low Hb): HR 1.38; Class 3 (rapid decline): HR 1.21
Primary Outcome: 28-day mortality
Nnt Or Sensitivity: Hazard ratios suggest 38% and 21% increased mortality risk for Classes 1 and 3 respectively
Confidence Interval: Class 1: 95% CI 1.18-1.62; Class 3: 95% CI 1.03-1.42
Clinical Application
Requires sophisticated trajectory modeling software; hemoglobin monitoring is routine in ICU Relevant to Australian ICUs; hemoglobin monitoring aligns with ANZICS guidelines; may inform transfusion decisions under National Blood Authority Patient Blood Management Guidelines Elderly ICU patients with sepsis requiring hemoglobin monitoring
Abstract
BACKGROUND: Anemia is a common complication in sepsis and is associated with poor prognosis. However, there are few studies on the dynamic changes in hemoglobin (Hb) levels and their relationship with prognosis in elderly patients with sepsis. This study aims to retrospectively investigate the relationship between Hb trajectories and 28-day mortality in this population. METHODS: This retrospective observational study used data from 4,961 elderly patients with sepsis extracted from the MIMIC-IV database(2008-2019). Hb trajectories were identified using a Joint Latent Class Model (JLCM) for longitudinal pattern classification. Following validation of proportional hazards assumptions (Schoenfeld residual test), we assessed the prognostic relationship between Hb trajectories and 28-day mortality using multivariable Cox regression models and Kaplan-Meier survival curves. Sensitivity analyses included sex-stratified multivariable Cox regression, subgroup analysis, and E-value assessment. RESULTS: Hb trajectories were classified into three patterns: Class 1 with persistently low levels, Class 2 with medium levels and a gradual decline, and Class 3 with a rapid decline from higher levels. Using Class 2 as the reference, multivariable Cox regression showed that Class 1 (HR = 1.38, 95% CI = 1.18-1.62, p < 0.001) and Class 3 (HR = 1.21, 95% CI = 1.03-1.42, p = 0.020) were associated with higher 28-day mortality. Kaplan-Meier curves indicated the lowest survival probability in Class 1 and the highest in Class 2. Gender-specific analysis revealed consistent trajectory patterns between males and females, but higher Hb values in males. The predictive power of the rapid decline pattern for early mortality was stronger in males. CONCLUSION: The Hb trajectories in elderly sepsis patients are significantly associated with early mortality. Persistently low levels and rapid declines in Hb are indicators of poor prognosis.
References
- 1.Zeng, Y., Wang, J., Liu, C., & Zhang, J. (2024). Association between hemoglobin dynamic trajectories and 28-day mortality in elderly patients with sepsis: A retrospective cohort study using the MIMIC-IV database. PLoS One. https://doi.org/10.1371/journal.pone.0327443
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