RENAL-METABOLIC RESERVE INDEX FOR CARDIORENAL RISK STRATIFICATION IN CRITICALLY ILL PATIENTS WITH SEPSIS

Abstract

Objective: To evaluate whether the admission renal-metabolic reserve index (RMRI), defined as (blood urea nitrogen + glucose)/albumin, was associated with in-hospital mortality in intensive care unit (ICU) patients with sepsis and to compare its prognostic performance with BAR and GAR. Methods: This retrospective cohort study used MIMIC-IV v3.1. Adults in the first ICU stay who met Sepsis-3 criteria near ICU admission and had blood urea nitrogen, glucose, and albumin measured from 6 hours before to 24 hours after ICU admission were eligible. Patients with end-stage renal disease or chronic dialysis were excluded. The primary outcome was in-hospital mortality. Logistic regression, restricted cubic splines, AUROC analysis, DeLong testing, subgroup analyses, and sensitivity analyses were performed. Results: The locked analytic cohort included 5,736 patients, and 1,251 (21.8%) died in hospital. RMRI was higher in non-survivors than survivors (64.7 [47.9-91.7] vs 52.1 [40.3-70.5]). RMRI remained associated with in-hospital mortality after multivariable adjustment (adjusted odds ratio per 1-SD, 1.33; 95% CI, 1.25-1.43; P < 0.001). Quartile 4 had an adjusted odds ratio of 2.35 (95% CI, 1.91-2.90; P < 0.001) versus quartile 1. Restricted cubic splines showed non-linearity (P = 0.001). AUROC increased from 0.723 for the clinical base model to 0.735 after RMRI addition, to 0.729 after GAR addition, and to 0.744 after BAR addition. Conclusion: Admission RMRI was independently associated with in-hospital mortality in ICU patients with sepsis and improved discrimination beyond the clinical base model and GAR. BAR remained the strongest comparator.

Keywords

• hypoalbuminemia
• stress hyperglycemia
• critical illness
• prognosis
• biomarker

Supporting Institution

No specific funding was received for this work..

Project Number

N/A

Ethical Statement

This study used de-identified data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Access to the database requires credentialing and completion of human research protections training. The project was additionally reviewed and approved by the Academic Board of the Department of Cardiology, Bezmialem Vakif University Faculty of Medicine (meeting no. 5, decision no. 1, 31 March 2026). The study was conducted in accordance with the Declaration of Helsinki. Written informed consent was waived because all protected health information had been removed from the de-identified database.

Thanks

none

BÖBREK-METABOLİK REZERV İNDEKSİ: SEPSİSLİ KRİTİK HASTALARDA KARDİYORENAL RİSK SINIFLANDIRMASI

Abstract

Amaç: Başvuru renal-metabolik rezerv indeksinin (RMRI), yani (kan üre nitrojeni + glukoz)/albümin oranının, sepsisli yoğun bakım hastalarında hastane içi mortalite ile ilişkisini değerlendirmek ve prognostik performansını BAR ve GAR ile karşılaştırmak. Yöntem: Bu retrospektif kohort çalışmasında MIMIC-IV v3.1 kullanıldı. İlk yoğun bakım yatışında, yoğun bakım kabulü çevresinde Sepsis-3 ölçütlerini karşılayan ve yoğun bakım kabulünden 6 saat önce ile 24 saat sonra arasında kan üre nitrojeni, glukoz ve albümin ölçümü bulunan erişkinler dahil edildi. Son dönem böbrek yetmezliği veya kronik diyaliz öyküsü olan hastalar dışlandı. Birincil sonlanım hastane içi mortaliteydi. Lojistik regresyon, restricted cubic spline, AUROC analizi, DeLong testi, alt grup analizleri ve duyarlılık analizleri yapıldı. Bulgular: Kilitli analitik kohort 5.736 hastadan oluştu ve 1.251 hasta (%21,8) hastanede öldü. RMRI, yaşamını yitirenlerde yaşayanlara göre daha yüksekti (64,7 [47,9-91,7] ve 52,1 [40,3-70,5]). RMRI, çok değişkenli düzeltme sonrasında da hastane içi mortalite ile ilişkili kaldı (1 SD artış için düzeltilmiş odds oranı 1,33; %95 GA 1,25-1,43; P < 0,001). Dördüncü çeyreğin birinci çeyreğe göre düzeltilmiş odds oranı 2,35 idi (%95 GA 1,91-2,90; P < 0,001). Restricted cubic spline analizi doğrusal olmayan ilişki gösterdi (P = 0,001). AUROC, klinik temel modelde 0,723 iken RMRI eklenince 0,735, GAR eklenince 0,729 ve BAR eklenince 0,744 oldu. Sonuç: Başvuru RMRI, sepsisli yoğun bakım hastalarında hastane içi mortalite ile bağımsız olarak ilişkiliydi ve klinik temel model ile GAR’ın ötesinde ayrım gücünü artırdı. En güçlü karşılaştırıcı BAR olarak kaldı.

Keywords

• hipoalbüminemi
• stres hiperglisemisi
• kritik hastalık
• prognoz
• biyobelirteç

Supporting Institution

Yok

Project Number

N/A

Ethical Statement

Bu çalışma, Medical Information Mart for Intensive Care IV (MIMIC-IV) veri tabanından elde edilen kimliksizleştirilmiş veriler kullanılarak yürütülmüştür. Veri tabanına erişim, yetkilendirme ve insan araştırmaları koruma eğitiminin tamamlanmasını gerektirir. Proje ayrıca Bezmialem Vakıf Üniversitesi Tıp Fakültesi Kardiyoloji Anabilim Dalı Akademik Kurulu tarafından değerlendirilmiş ve onaylanmıştır (toplantı no: 5, karar no: 1, 31 Mart 2026). Çalışma Helsinki Bildirgesi’ne uygun olarak yürütülmüştür. Kimliği tanımlayıcı tüm bilgiler veritabanından kaldırıldığı için yazılı aydınlatılmış onam aranmadı.

Thanks

Yok

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