Predictive Value of Hemoglobin to Red Blood Cell Distribution Width Ratio in the Prognosis of Patients with Pulmonary Arterial Hypertension
JIN Fangfang
JI Jianmin
ZHANG Jianqing
Abstract：Objective To investigate the predictive value of hemoglobin-to-red blood cell distribution width ratio(HRR)for 365-day all-cause mortality in patients with pulmonary arterial hypertension and identify its threshold effect.Methods Using the MIMIC-Ⅳ 3.1 database,3 261 adult pulmonary arterial hypertension patients with complete data during their first ICU admission were retrospectively enrolled.Patients were divided into three groups based on HRR tertiles:group 1 was HRR＜0.586 6;group 2 was 0.586 6 ≤ HRR≤0.796 2;group 3 was HRR＞0.796 2.The primary endpoint was 365-day all-cause mortality.Restricted cubic splines(RCS)were used to analyze the nonlinear relationship between HRR and mortality.Kaplan-Meier curves assessed cumulative survival rates at 365-day follow-up,with log-rank test for comparison.Multivariable Cox regression models analyzed the relationship between HRR and mortality in pulmonary arterial hypertension patients.Receiver operating characteristic(ROC)curves evaluated HRR's predictive ability for clinical mortality.Subgroup analysis aimed to test model robustness and identify interaction effects.Results HRR showed a significant nonlinear negative correlation with 365-day mortality,revealing a threshold effect(inflection point=0.42).For each 1-unit increase in HRR,mortality risk decreased by 98％(HR=0.02,95％CI:0-0.25)in the ≤0.42 segment and by 56％(HR=0.44,95％CI:0.29-0.67)in the＞0.42 segment.Kaplan-Meier curves demonstrated the highest cumulative survival rate in group 3(log-rank P＜0.001).Multivariable Cox analysis confirmed HRR as an independent protective factor(HR=0.36,95％CI:0.25-0.53,P＜0.001);mortality risks in groups 2 and 3 were reduced by 23％(HR=0.77,95％CI:0.66-0.90,P＜0.001)and 33％(HR=0.67,95％CI:0.56-0.79,P＜0.001),respectively,compared to group 1.ROC analysis showed an area under the curve of 0.605(95％CI:0.59-0.62)for HRR predicting mortality risk;subgroup analysis revealed stronger protective effects in hypertensive patients.Conclusion HRR demonstrates a significant nonlinear negative correlation with mortality in pulmonary arterial hypertension patients.As a simple and cost-effective biomarker,HRR holds important value in prognostic assessment of pulmonary arterial hypertension,aiding in the identification of high-risk patients and guiding clinical decision-making.
Keywords：pulmonary arterial hypertensionratio of hemoglobin to red blood cell distribution widthprognosisall-cause deathpredict
Publication Date：2026-07-13
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：5( 2315-2319 )