Abstract
Obstructive sleep apnea (OSA) is prevalent in critically ill patients and associated with increased mortality. This study aimed to investigate the association between red blood cell distribution width (RDW) at admission and one-year mortality in critically ill OSA patients. A retrospective cohort study involving 1950 critically ill patients with OSA from the MIMIC-IV (v3.1) database. Kaplan-Meier survival analysis, multivariable Cox regression, and restricted cubic spline (RCS) analyses were performed to evaluate the association between RDW and all-cause mortality. Subgroup analyses were performed to assess the consistency of the RDW-mortality association and identify potential interaction effects. The incidence of mortality increased significantly across RDW quartiles (Q1: 4.6% vs. Q2: 12.1% vs. Q3: 18.4% vs. Q4: 34.7%, P < 0.001). Kaplan-Meier analysis demonstrated significantly higher 30-day and one-year all-cause mortality among patients in the higher RDW quartiles (log-rank P< 0.001). Multivariate Cox regression analysis revealed that RDW levels were independently correlated with one-year mortality after adjusting for multiple variables for both continuous (hazard ratio [HR] 1.15, 95% confidence interval [CI]: 1.10–1.20; P < 0.001) and categorical comparisons (Q4 vs. Q1: HR 4.42, 95% CI: 2.67–7.31; P< 0.001). RCS regression confirmed a significant positive relationship between RDW and the risk of short- or long-term mortality (Pfor overall <0.001). Subgroup analysis confirmed the robustness of the results and identified interactions between RDW and White race, and BMI status (P for interaction = 0.011 and 0.052, respectively). This study established a positive association between RDW and all-cause mortality in OSA patients admitted to the ICU. Higher RDW levels were associated with an increased risk of short- and long-term all-cause mortalities.
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Data availability
The publicly available datasets used in this study can be accessed from online repositories. Data were obtained from [https://physionet.org/content/mimiciv/3.1/](https:/physionet.org/content/mimiciv/3.1) .
Abbreviations
- OSA:
-
Obstructive sleep apnea
- BMI:
-
Body mass index
- SBP:
-
Systolic blood pressure
- DBP:
-
Diastolic blood pressure
- MBP:
-
Mean blood pressure
- HR:
-
Heart rate
- RR:
-
Respiratory rate
- SpO2 :
-
Oxygen saturation
- WBC:
-
White blood cell
- RBC:
-
Red blood cell
- RDW:
-
Red cell distribution width
- BUN:
-
Urea nitrogen
- INR:
-
International normalized ratio
- PT:
-
Prothrombin time
- APTT:
-
Activated partial prothrombin time
- MI:
-
Myocardial infarction
- COPD:
-
Chronic obstructive pulmonary disease
- SOFA:
-
Sequential organ failure assessment
- SAPS II:
-
Simplified acute physiology score
- APS III:
-
Acute physiology score III
- CCI:
-
Charlson comorbidity index
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Funding
This study was supported by the National Natural Science Foundation of China (82100359 and 82500364).
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Tuo Han: Conceptualization, Project administration, Supervision, Writing, review, and editing. Chunyan Zhang and Jing Xiao: Data curation, formal analysis, Investigation, Methodology, Visualization, Writing of the original draft. Xiyu Gao and Chen Guo: Data curation, formal analysis, Software, Writing, reviewing, and editing. Na Feng, Yan Zhang: Conceptualization, Funding acquisition, Methodology and Writing, review, and editing. All the authors approved the final version of the manuscript.
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The review boards of Massachusetts Institute of Technology (MIT) and Beth Israel Deaconess Medical Center approved the use of the MIMIC-IV database. Since the participants were anonymized and de-identified, this study was exempt from the requirements for ethical approval and informed consent.
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Zhang, C., Xiao, J., Gao, X. et al. The role of red blood cell distribution width in prognosis prediction among critically ill patients with obstructive sleep apnea: Insights from the MIMIC-IV database. Sci Rep (2026). https://doi.org/10.1038/s41598-026-43197-1
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DOI: https://doi.org/10.1038/s41598-026-43197-1
