Development and Validation of a Scoring System That Includes Corrected QT Interval for Risk Analysis of Patients With Cirrhosis and Gastrointestinal Bleeding

Abstract

The electrocardiographic QT interval frequently is prolonged in patients with cirrhosis. Acute gastrointestinal bleeding further prolongs corrected QT (QTc) in patients with cirrhosis, which has been associated with an increased risk of death within 6 weeks. We aimed to confirm these findings and develop a mortality risk index that incorporates QTc. We collected data from 274 patients with cirrhosis and acute gastrointestinal bleeding from any cause admitted to a hospital in Bologna, Italy, from January 2001 through December 2012 (training set). We used logistic regression analysis to identify patient factors associated with death within 6 weeks (6-week mortality). We validated our findings by using data from 200 patients with cirrhosis and gastrointestinal bleeding treated at 2 separate hospitals in Italy, from 2001 through 2016 and 2007 through 2012. Our primary aim was to confirm the prognostic effects of prolonged QTc in a large population of patients and develop a 6-week mortality risk score for acute gastrointestinal bleeding from any cause that incorporates the QTc interval. In the training set, QTc greater than 456 ms, the model for end-stage liver disease-sodium (MELD-Na) score, previous bleeding, and serum albumin concentration were associated independently with 6-week mortality. We combined these parameters to create a risk scoring system that we named MELD-Na acute gastrointestinal bleeding (MELDNa-AGIB). In the validation set, the MELDNa-AGIB identified patients who died within 6 weeks with an area under the receiver operating characteristic curve (AUROC) of 0.888; this value was higher than that of the MELD score (AUROC, 0.838; P= .031), MELD score with updated calibration (AUROC, 0.837; P= .029), Child-Turcotte-Pugh score (AUROC, 0.789; P= .004), D'Amico score (AUROC, 0.761; P= .003), and Augustin score (AUROC, 0.792; P= .001), with a net reclassification improvement better than the MELD-Na score (0.266; P= .045). In calibration, the MELDNa-AGIB produced a high score in the Hosmer-Lemeshow test (P= .947), which was superior to that of MELD-Na (P= .146). In the training set, only 6.3% of patients with MELDNa-AGIB scores of 4 or less died within 6 weeks. Among patients with a scores of 9, 16, and 25 or higher, 15.5%, 41.5%, and 81% or more patients died within 6 weeks, respectively. The probability of survival progressively and significantly decreased with increasing scores in the training and validation sets. We confirmed QTc as an independent predictor of 6-week mortality in a large population of patients with cirrhosis and acute gastrointestinal bleeding. The combination of QTc, MELD-Na, previous bleeding, and serum albumin (the MELDNa-AGIB score) accurately determines the risk of 6-week mortality, providing timely identification of patients at very high risk of death.