Abstract
Current risk stratification for Post-cardiac Arrest Syndrome (PCAS) relies mainly on static admission variables and may fail to capture the dynamic systemic evolution. This study aimed to identify trajectory-defined thrombo-inflammatory phenotypes in PCAS using longitudinal trajectories of platelets, white blood cells (WBC), hemoglobin, and body temperature, and to evaluate their association with 30-day ICU mortality. We conducted a multicenter retrospective cohort study using the MIMIC-IV, MIMIC-III, and eICU-CRD databases, including adult patients with ICU stays of 2-90 days after cardiac arrest. A Multivariate Process Joint Latent Class Mixed Model (mJLCMM) identified latent classes from 30-day biomarker trajectories. The primary outcome was 30-day ICU mortality. Associations were evaluated using Inverse Probability Weighting (IPW) and Doubly Robust Estimation (DRE). Prognostic accuracy was compared against SOFA and OASIS scores using time-dependent Receiver Operating Characteristic (ROC) analysis. A total of 5,099 patients were included. Two phenotypes were identified: Class 1 (“Rapid Decline and Recovery”) and Class 2 (“Mild Decline and Recovery”). Class 1 was associated with higher 30-day ICU mortality (eICU: 46.7%; MIMIC: 24.6%). In doubly robust analyses, the class 2 remained associated with lower ICU mortality in both cohorts, with odds ratios (ORs) of 0.82 (95% CI, 0.72-0.96) in eICU and 0.74 (95% CI, 0.55-0.95) in MIMIC. By Day 30, the trajectory model outperformed SOFA and OASIS, with an AUC of 0.74 versus 0.54 and 0.59, respectively. This trajectory-based classification showed superior prognostic performance for 30-day ICU mortality and highlights the potential value of dynamic monitoring in post-cardiac arrest management.
Keywords
Introduction
Sudden cardiac arrest (SCA) remains a significant global public health crisis and a leading cause of death worldwide. Despite advancements in resuscitation, survival rates for out-of-hospital cardiac arrest (OHCA) remain low, plateauing near 10%. 1 Approximately 350,000 individuals in the United States alone suffer from OHCA annually. 2 Although only a minority of patients achieve return of spontaneous circulation (ROSC), successful resuscitation at hospital admission represents a critical determinant of survival. 3 However, ROSC does not guarantee favorable neurological outcomes. Many patients experience post-resuscitation complications, including re-arrest, multi-organ dysfunction, and neurological deterioration. 4 Consequently, mortality rates among resuscitated patients admitted to the intensive care unit (ICU) remain substantially high. 5
Among the multifactorial mechanisms driving multiple organ dysfunction in Post-Cardiac Arrest Syndrome (PCAS), a key driver is a “sepsis-like” systemic inflammatory response. This phenomenon is increasingly recognized as “thrombo-inflammation”—a pathological collision between the immune system and the hemostatic machinery. 6 Following global ischemia, reperfusion-induced endothelial activation and glycocalyx shedding expose the subendothelial matrix, catalyzing platelet aggregation and leukocyte recruitment that culminate in microvascular thrombosis and disseminated intravascular coagulation (DIC). 7 As a conceptual background for our analysis, platelets and white blood cells (WBCs) are understood to serve as active effectors within this cascade. Although these specific cellular interactions were not directly measured in the current study, biologically plausible models suggest that activated platelets recruit neutrophils to the injured endothelium, promoting Neutrophil Extracellular Trap (NET) formation—a process that, in theory, propagates thrombosis and tissue injury. 8 While modern prognostication for PCAS typically employs a multimodal approach—integrating neurological examination, electrophysiology, and neuroimaging 9 —the laboratory component often relies on static biomarkers obtained at admission 10 (e.g., initial lactate, pH) or snapshot severity scores (e.g., SOFA, APACHE). 11 These static measures fail to capture the decline in physiological deterioration or the trajectory of recovery, often leading to inaccurate risk stratification.12,13 While traditional statistical methods, such as logistic regression or linear mixed models, are robust for many clinical applications, analyzing longitudinal ICU data presents a specific challenge known as ‘informative dropout'—the bias introduced when the most severely ill patients die early and cease to contribute data to the longitudinal record.14,15 The Multivariate Process Joint Latent Class Mixed Model (mJLCMM) specifically addresses this limitation by jointly modeling longitudinal biomarkers and the survival outcome, enabling more accurate estimation of dynamic physiological trajectories. 16
In this study, we leveraged longitudinal data from multiple multicenter critical care databases, including two versions of the Medical Information Mart for Intensive Care (MIMIC-III and MIMIC-IV version 3.1) and the eICU Collaborative Research Database (eICU-CRD version 2.0). We hypothesized that specific joint trajectories of thrombo-inflammatory markers (platelets, WBCs, hemoglobin) and body temperature during the early post-resuscitation phase would identify distinct trajectory-defined subgroups associated with divergent survival outcomes. By applying mJLCMM, we aimed to identify these model-derived latent classes to better understand disease heterogeneity, thereby providing a conceptual foundation for future prospective studies exploring early prognostication and personalized management strategies for patients with PCAS.
Method
Data Source
This multicenter retrospective cohort study, utilizing data from the MIMIC-III, MIMIC-IV (version 3.1), and eICU-CRD (v2.0) databases, was conducted and reported in accordance with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. 17 MIMIC-III contains records from over 23,000 patients admitted to the Intensive Care Unit (ICU) at Beth Israel Deaconess Medical Center (BIDMC) between 2001 and 2008. 18 MIMIC-IV v3.1, the subsequent version, includes comprehensive medical records for all patients admitted to the ICU or emergency department at BIDMC from 2008 to 2022. 19 Additionally, the eICU-CRD v2.0 comprises records from over 200,000 ICU patients across multiple centers during 2014 and 2015. 20
The use of the MIMIC database was approved by the Institutional Review Board (IRB) of Beth Israel Deaconess Medical Center (BIDMC), which granted a waiver of informed consent. Data collection and release were additionally approved by the Massachusetts Institute of Technology (MIT) Committee on the Use of Humans as Experimental Subjects (Protocol No. 0403000206). All data were deidentified in compliance with the Health Insurance Portability and Accountability Act (HIPAA). As this study involved secondary analysis of publicly available, anonymized data, additional ethical approval was not required.
Participants
The study population comprised adults (≥18 years) extracted from the MIMIC-IV v3.1, MIMIC-III, and eICU-CRD v2.0 databases. Eligibility was determined based on the following criteria. 1
The following exclusion criteria were applied: (1) patients with multiple ICU admissions (only the first admission was included); (2) age <18 years; (3) ICU length of stay <24 hours or >90 days; (4) missing any baseline measurement within the first 24 hours of ICU admission (vital signs: heart rate, respiration, systolic/diastolic blood pressure, mean arterial pressure, temperature; laboratory values: white blood cell count, hemoglobin, platelet count; (5) having fewer than two measurements of vital signs, white blood cell count, or platelet count during the 30-day post-admission period.
Data Extraction, Handling Missing Data
Clinical data were extracted from the databases using Structured Query Language (SQL), encompassing five categories of information: (1) demographics, laboratory parameters, and severity scores obtained within the first 24 hours of intensive care unit (ICU) admission, including age, sex, serum calcium, alanine aminotransferase (ALT), aspartate aminotransferase (AST), pH, fraction of inspired oxygen (FiO2), arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), bicarbonate (HCO3-), peripheral capillary oxygen saturation (SpO2), anion gap, albumin, creatinine, urea nitrogen (BUN), glucose, hematocrit, hemoglobin, potassium, international normalized ratio (INR), prothrombin time (PT), Sequential Organ Failure Assessment (SOFA) score, and Oxford Acute Severity of Illness Score (OASIS); (2) longitudinal measurements collected over a 30-day period following ICU admission, including WBC, hemoglobin, body temperature, and platelet count; (3) ICU clinical details, including duration of ICU stay, ICU and hospital survival status, mechanical ventilation and renal replacement therapy within the first 24 hours, blood and platelet transfusion, and vasoactive agent administration; (4) comorbidities, including chronic renal disease, diabetes mellitus, history of myocardial infarction, congestive heart failure (CHF), peripheral vascular disease, chronic obstructive pulmonary disease (COPD), connective tissue disease, peptic ulcer disease, cerebrovascular disease, and severe liver disease; and (5) life support interventions administered within the first 24 hours of ICU admission, specifically mechanical ventilation and renal replacement therapy. For variables with multiple measurements within the same day, the value reflecting the most severe condition was selected for analysis.
Variables with more than 30% missing data were excluded from further analysis (Figure S1). For variables with ≤30% missing values, multiple imputation was performed using predictive mean matching (PMM) via the ‘mice’ package (version 3.16.0) in R. 21
Outcome
The primary outcome was 30-day ICU mortality after ICU admission; the secondary outcomes comprised 30-day survival status and time to death within 30 days. Survival time was measured from ICU admission to death, with right-censoring at ICU discharge or 30 days for survivors.
Statistical Analysis
Step 1: Identification of Subpopulations
To identify subpopulations with distinct trajectories of platelets, WBC, hemoglobin, and body temperature, we employed a Multivariate Process Joint Latent Class Mixed Model (MPJLCMM). This model jointly analyzes longitudinal measurements of the four biomarkers while identifying latent classes with heterogeneous trajectory patterns. Nonlinear temporal trends were modeled using natural cubic splines with three internal knots placed at percentiles of the time distribution. The model structure was specified as follows: Time Scale and Fixed Effects: Time was defined continuously as days from ICU admission up to a maximum of 30 days. To capture nonlinear physiological dynamics, the temporal trends for the biomarkers were modeled using natural cubic splines with 3 degrees of freedom. Random Effects Structure: To account for intra-individual correlation and baseline heterogeneity, the models incorporated patient-specific random intercepts and random slopes for the spline terms. Class Membership Sub-model: The probability of latent class assignment was estimated without baseline covariates to ensure that the derived trajectory patterns were purely data-driven. The optimal number of latent classes was determined by evaluating multiple fit indices: Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), sample-adjusted BIC (SABIC), and entropy. 22 Analyses were performed using the lcmm package (version 2.0.2) in R.
Step 2: Trajectory Visualization
We compared clinical characteristics and laboratory values between the identified latent classes using appropriate statistical tests (t-test/Mann-Whitney for continuous variables; chi-square/Fisher’s exact for categorical variables) (Table S2 and S3). Biomarker trajectories were plotted for each class, and 30-day survival was compared using Kaplan-Meier analysis with the log-rank test.
Step 3: Independent Association With Outcomes (Double Robust Estimation)
Variable selection employed a two-step approach. First, baseline variables with pairwise correlation coefficients ≥ 0.5 were excluded to address high intercorrelation (Figure S2 and S3). Second, from the remaining variables, those demonstrating clinical relevance and a univariate logistic association with the outcome (p < 0.05), while maintaining acceptable collinearity (variance inflation factor [VIF] < 5), were retained as potential confounders (Tables S6 and S7). Subsequently, propensity scores for latent class membership were estimated using gradient boosting machine models implemented in the R ‘twang’ package, with models iteratively optimized to achieve covariate balance.
Step 4: Sensitivity Analysis
To evaluate the robustness of our findings across different statistical methodologies, sensitivity analyses were performed using three distinct analytical approaches: (1) a fully adjusted multivariate logistic regression model was fitted, in which trajectory phenotype was entered as the main exposure and all selected baseline covariates were included directly in the outcome model (2) an inverse probability weighting (IPW) analysis was conducted using propensity scores for latent class membership estimated by gradient boosting machine models; these weights were used to generate a pseudo-population with improved balance of measured baseline covariates between the two phenotype groups, after which a weighted logistic regression model was fitted (3) a doubly robust estimation (DRE) approach that combined inverse probability weighting based on the propensity score with an additional adjusted outcome regression model, thereby addressing potential confounding from imbalanced covariates.
Step 5: Subgroup Analysis
A subgroup analysis was conducted on the cardiac arrest cohort derived from the MIMIC and eICU-CRD databases to evaluate the consistency of the association between two distinct trajectory patterns and cardiac arrest outcomes across various patient subgroups. Subgroups were stratified according to demographic and clinical characteristics, including age, comorbidities, platelet transfusion, red blood cell (RBC) transfusion, mechanical ventilation, renal replacement therapy, anticoagulation therapy, and antiplatelet therapy. Interaction effects between these factors and trajectory patterns were assessed by comparing two logistic regression models: a baseline model and an extended model incorporating interaction terms.
To assess the prognostic accuracy of the derived clinical trajectory phenotypes relative to established severity scores (SOFA and OASIS), we performed time-dependent Receiver Operating Characteristic (ROC) curve analyses. Time-dependent Area Under the Curve (AUC) values were estimated at 3-, 10-, and 30 days post-admission to capture dynamic changes in predictive utility over the clinical course. All time-dependent ROC analyses were conducted using the ‘timeROC’ package in R.
All statistical analyses were conducted using R software (version 4.0.5). Continuous variables are presented as mean ± standard deviation (SD) for normally distributed data or as median with interquartile range (IQR) for non-normally distributed data. Between-group comparisons for continuous variables were performed using Student's t-test for normally distributed data and the Mann-Whitney U test for non-normally distributed data. Categorical variables are expressed as frequencies and percentages and were analyzed using the chi-square test or Fisher’s exact test, as appropriate.
Results
Baseline Characteristics
A total of 3,776 patients from the eICU-CRD database were included in the analysis, of whom 1,477 (39.1%) died before hospital discharge; the MIMIC cohort included 1,323 patients (Figure 1). As illustrated in Table 1, Non-survivors were slightly older than survivors (median age: 66.0 vs. 64.0 years; P = 0.001) and had a significantly higher proportion of females (44.6% vs. 37.7%; P < 0.001). Significant metabolic and organ dysfunction were observed in the non-survival group. Liver enzymes were markedly elevated in non-survivors compared to survivors, including ALT (85.0 vs. 54.0 U/L; P < 0.001) and AST (135 vs. 75.0 U/L; P < 0.001). Metabolic disorder was also more pronounced in non-survivors, characterized by hyperglycemia (239 vs. 192 mg/dL; P < 0.001) and an increased anion gap (17.0 vs. 14.0 mmol/L; P < 0.001). Additionally, non-survivors exhibited worse renal function (creatinine: 1.75 vs. 1.36 mg/dL; P < 0.001; BUN: 30.0 vs. 25.0 mg/dL; P < 0.001) and coagulopathy, indicated by prolonged PT (16.1s vs. 15.1s, P < 0.001) and elevated INR (1.40 vs. 1.23) (P < 0.001 for both). Hemodynamic instability was apparent in non-survivors, who presented with higher heart rates (113 vs. 106 bpm; P < 0.001) and elevated blood pressures. Regarding interventions, non-survivors had higher rates of vasopressor use (59.5% vs. 42.8%; P < 0.001) and mechanical ventilation within the first 24 hours (97.9% vs. 89.6%; P < 0.001), but received anticoagulation (42.9% vs. 53.5%; P < 0.001) and platelet infusion less frequently (1.30% vs. 2.91%; P = 0.001). Among comorbidities, only congestive heart failure and COPD showed significant associations with ICU mortality. Consequently, disease severity scores were markedly higher in non-survivors, including OASIS (41.0 vs. 36.0; P < 0.001) and SOFA scores (10.0 vs. 8.00; P < 0.001). This distribution was similarly observed in the MIMIC database (Table S1). Flowchart of patient selection and study cohort derivation. Clinical Baseline Characteristics of Patients in eICU-CRD
Identification of Subpopulations Using the MJLCMM
Metric for Determining Optimal Class Quantity

Longitudinal trajectories of platelet count in the derived latent classes.

Longitudinal trajectories of hemoglobin levels across latent classes.

Longitudinal trajectories of white blood cell (WBC) count across latent classes.

Longitudinal trajectories of body temperature across latent classes.
Clinical Characteristics of Differential Trajectory Patterns and Their Association With 30-day ICU Mortality: A Propensity Score-weighted Analysis
Comparisons of clinical baseline characteristics between the two trajectory patterns are detailed in Table S2 and Table S3. Across both databases, Class 1 exhibited a more severe pro-inflammatory and metabolically deranged profile. Specifically, in the eICU-CRD dataset, Class 1 patients presented with markedly higher white blood cell counts (20.9 vs. 13.0 × 109/L; P < 0.001), elevated ALT levels (93.0 vs. 54.0 IU/L; P < 0.001), and severe hyperglycemia (247 vs. 191 mg/dL; P < 0.001) compared to Class 2. This pattern of higher severity was mirrored in the MIMIC cohort; Class 1 necessitated more aggressive life support interventions; vasopressor use (65.5% vs. 42.4%; P < 0.001) and mechanical ventilation (88.1% vs. 80.3%; P < 0.001) were significantly more frequent in Class 1 than in Class 2. Class 1 exhibited higher ICU mortality rates in both eICU-CRD (46.7% vs. 35.0%; P < 0.001) and MIMIC (24.6% vs. 16.0%; P < 0.001).
Primary Outcome Analysis With Three Different Models in the Cardiac Arrest Cohort of eICU-CRD and MIMIC-III and IV

Information on balance statistics.
Subgroup Analysis of Clinical Trajectory Phenotypes and Their Association With 30-Day ICU Mortality
As illustrated in Figure 7 and Figure S4, the Class 1 pattern was associated with significantly higher odds of 30-day ICU mortality than the Class 2 pattern in the majority of subgroups in both MIMIC and eICU-CRD, except for a small subset of subgroups with insufficient sample sizes. However, significant heterogeneity was observed regarding the use of vasoactive agents (P for interaction < 0.01) and RBC infusion (P for interaction = 0.04). Specifically, the association was more pronounced in patients not receiving vasoactive agents (OR 2.11, 95% CI 1.68–2.65) compared to those who did, while the risk relationship was attenuated and lost statistical significance in patients receiving RBC infusion (OR 0.97, 95% CI 0.57–1.68), indicating a potential interaction between these treatments and trajectory patterns regarding ICU mortality risk. Despite these specific interactions, the discriminative direction of the main results remained stable across all other prespecified subgroups and in the MIMIC database (Figure S4). To further validate the prognostic value of the classification, we performed a Kaplan-Meier survival analysis over a 30-day observation period in both datasets (Figure 8). The survival curves revealed a significant divergence between the two groups shortly after admission. Patients with Class 1 exhibited a significantly steeper decline in cumulative survival probability than those with Class 2 (log-rank test, P < 0.001), indicating that Class 1 is strongly associated with worse clinical outcomes and higher short-term ICU mortality. Forest plot of subgroup analysis for the association between trajectory patterns and 30-day ICU mortality in the eICU-CRD cohort Kaplan-Meier survival estimates stratified by trajectory phenotype.

To evaluate the prognostic accuracy of the derived trajectory phenotypes relative to established clinical severity scores, we performed a time-dependent Receiver Operating Characteristic (ROC) analysis within the eICU-CRD cohort. We compared the discriminative ability of the trajectory model with that of the OASIS and SOFA scores at 3-, 10-, and 30-day post-admission. In the acute phase (Day 3), the trajectory model yielded an Area Under the Curve (AUC) of 0.65, performing comparably to the SOFA (AUC=0.64) and OASIS (AUC=0.63) scores (Figure 9A). However, the predictive superiority of the Trajectory model became increasingly pronounced at later time points as the predictive power of static admission scores decayed. By Day 10, the Trajectory model maintained an AUC of 0.67, surpassing both OASIS (AUC=0.55) and SOFA (AUC=0.58) (Figure 9B). Most notably, at Day 30, the trajectory model demonstrated robust predictive capability with an AUC of 0.74, whereas the performance of conventional scoring systems deteriorated significantly, with OASIS and SOFA dropping to 0.59 and 0.54, respectively (Figure 9C). This divergence highlights that while static admission scores are sufficient for immediate risk assessment, the dynamic trajectory-based classification offers significantly superior long-term risk stratification for PCAS patients. Time-dependent Receiver Operating Characteristic (ROC) analysis comparing prognostic accuracy.
Discussion
Current clinical frameworks for risk stratification in PCAS, including the APACHE and SOFA scores, predominantly rely on static biomarkers obtained at admission or at fixed time points.
23
While valuable for risk assessment, these snapshots fail to capture the dynamic progression of the “sepsis-like” syndrome that defines PCAS.
24
The physiological state after ROSC is dynamic, marked by the complex interaction between ischemia-reperfusion injury (IRI) and compensatory physiological mechanisms.25,26 PCAS represents a complex clinical entity characterized by significant disturbances in hemostatic balance following resuscitation.
27
A key manifestation of this dysregulation involves measurable alterations in platelet dynamics, reflecting widespread systemic injury and potential activation of pro-inflammatory and pro-coagulant pathways. These platelet-related changes have emerged as valuable prognostic biomarkers for predicting in-hospital mortality after ROSC.28,29 Several studies have identified specific hematological markers associated with PCAS outcomes. Mehmet K. Ero et al demonstrated that during the initial 48 hours post-cardiac arrest, low albumin, hemoglobin, hematocrit, and mean hemoglobin concentration, along with elevated red blood cell distribution width and urea levels, correlate with increased mortality.
30
Furthermore, the white blood cell-to-platelet ratio (WPR) exhibits a significant U-shaped relationship with mortality risk and serves as an independent prognostic biomarker for 28-day mortality in cardiac arrest patients.
31
Despite these advances, conventional static biomarker measurements remain limited in their ability to reflect the dynamic pathophysiology of PCAS
The pathological basis of PCAS involves ischemia-reperfusion injury that triggers a sepsis-like inflammatory response37,38
However, our study is subject to several limitations that are worth noting. Firstly, as a retrospective cohort study, this research design inherently limits our ability to infer causality and cannot establish causal relationships as definitive as those in randomized controlled trials. While this approach efficiently leverages existing data, it remains susceptible to several methodological limitations, including confounding factors, selection bias, and information bias. Although we employed comprehensive statistical methodologies—such as propensity score matching and doubly robust estimation—to adjust for measured confounders, it is important to note that these findings represent robust observational associations rather than confirmed causal effects, as the potential for unmeasured confounding remains. Moreover, despite consistent findings across the eICU-CRD and MIMIC cohorts, prospective validation in geographically and clinically distinct populations remains necessary, particularly for subgroups with limited sample size. Secondly, as a retrospective analysis of EHR databases, the study infers immunothrombosis and Neutrophil Extracellular Trap (NET) formation from trajectory patterns of standard markers (platelets, WBC). It does not directly measure specific biomarkers of NETs (e.g., H3Cit, MPO-DNA complexes)43,44 or platelet activation (e.g., P-selectin, soluble CD40L).45,46 Consequently, the mechanistic links discussed herein are inherently inferential and serve primarily as hypothesis-generating concepts. Future prospective translational studies are required to measure these specific mediators alongside clinical trajectories to validate these mechanistic links. Thirdly, although the overall sample size was large, some subgroup analyses may have been underpowered because of limited sample sizes within specific strata, potentially precluding the detection of significant associations in certain populations. In addition, because the subgroup analyses involved multiple interaction tests, the possibility of Type I error inflation cannot be excluded. Therefore, these subgroup findings should be interpreted cautiously as exploratory and hypothesis-generating, and their generalizability warrants further validation in future, adequately powered prospective studies.
Fourth, comparisons of clinical characteristics and outcomes between the derived trajectory phenotypes were based on assigning each patient to the latent class with the highest posterior probability. While this hard-classification approach facilitates conventional between-group statistical testing, it does not fully account for the probabilistic nature of latent class membership and the resulting classification uncertainty. However, the high entropy of the final multivariate integrated model (0.95), together with the favorable posterior classification metrics shown in Tables S4 and S5, suggests strong class separation and likely reduces, though does not eliminate, the impact of potential misclassification on these comparisons. Fifth, our study has inherent limitations stemming from the retrospective nature of the MIMIC and eICU-CRD databases. Specifically, the lack of granular pre-hospital emergency medical services (EMS) data prevented reliable differentiation between out-of-hospital and in-hospital cardiac arrest. At the same time, critical peri-arrest variables (e.g., exact time to ROSC, initial shockable rhythm) were largely unavailable, necessitating reliance on admission severity scores (SOFA and OASIS) as surrogates for initial insult severity.
Furthermore, the exclusion of patients with ICU length of stay <24 hours—implemented to ensure sufficient data points for robust trajectory modeling—introduces survivorship bias by omitting early deaths. Sixth, our primary outcome was limited to 30-day ICU mortality due to inherent constraints of the eICU and MIMIC databases, which precluded reliable tracking of post-discharge out-of-hospital survival. Additionally, these administrative datasets lack standardized, structured neurological assessments, such as the Cerebral Performance Category (CPC) scale, thereby preventing the evaluation of long-term neurological outcomes, which are critical endpoints in post-cardiac arrest care. Future prospective studies are essential to validate these dynamic thrombo-inflammatory phenotypes in relation to both long-term survival and neurological recovery.
Conclusion
This multicenter observational study identifies distinct clinical phenotypes in patients with PCAS based on specific dynamic trajectories of thrombo-inflammatory biomarkers. The “Rapid Decline and Recovery” was associated with higher 30-day ICU mortality and may represent a high-risk clinical subgroup. Trajectory-based classification showed promising long-term prognostic performance compared with static admission scores (e.g., SOFA, OASIS) in this cohort. Future prospective studies are warranted to validate these phenotypes and investigate whether precision interventions targeting the thrombo-inflammatory cascade can meaningfully inform therapeutic strategies and improve survival in this vulnerable population.
Supplemental Material
Supplemental Material -Trajectory-Defined Thrombo-Inflammatory Phenotypes Predict 30-Day ICU Mortality in Post-cardiac Arrest Syndrome: A Multicenter Retrospective Longitudinal Cohort Study
Supplemental Material for Trajectory-Defined Thrombo-Inflammatory Phenotypes Predict 30-Day ICU Mortality in Post-cardiac Arrest Syndrome: A Multicenter Retrospective Longitudinal Cohort Study by Guyu Zhang, Le An, ChenChen Hang, XingSheng Wang, Rui Shao, ZhenYu Shan, Ziren Tang in INQUIRY: The Journal of Health Care Organization, Provision, and Financing
Footnotes
Acknowledgments
We thank all Emergency Medicine Clinical Research Center participants, Beijing Chaoyang Hospital, Capital Medical University.
Ethical Considerations
The MIMIC and eICU databases are publicly available, and the creation of the research resource was reviewed by the Institutional Review Board at the Beth Israel Deaconess Medical Center. Permission to use the data was available in the Supplemental Material. The patient consent was waived as the data are wholly deidentified and retrospective from public databases.Access to this database was granted after one of the authors (GuyuZhang, certification ID: 55849941) completed the requisite NIH-mandated online training.
Consent to Participate
The database is publicly available and all patient data has been de-identified. The Institutional Review Boards (IRB) of the Massachusetts Institute of Technology (MIT) and Beth Israel Deaconess Medical Center (BIDMC) approved the database establishment and waived the need for informed consent.
Author Contributions
GZ collected the data, analyzed the data, and drafted the manuscript. LA, CCH, RS, and XSW extracted the data and participated in its design. ZYS participated in the literature research. ZT acted as the guarantor for the entire project, with responsibilities including manuscript review, study design, and overall supervision. All authors contributed to the article and approved the submitted version.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by the Beijing Municipal Science & Technology Commission, Administrative Commission of Zhongguancun Science Park No. Z251100006025022 and the Beijing Hospitals Authority’s Ascent Plan (DFL20240302).
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Data Availability Statement
The raw data supporting the conclusions of this article were available at Medical Information Mart for Intensive Care (PhysioNet), and eICU Collaborative Research Database (PhysioNet).
Clinical Trial Registration
This study is a retrospective analysis of a publicly available database and does not require clinical trial registration.
Supplemental Material
Supplemental material for this article is available online.
References
Supplementary Material
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