The Charlson Comorbidity Index is associated with risk of 30-day mortality in patients with myocardial injury after non-cardiac surgery

Sojin Kim,Ah Ran Oh,Ji-Hye Kwon,Jin-Ho Choi,Joonghyun Ahn,Kwangmo Yang,Jungchan Park,Ji Dong Sung,Joonhee Gook,Kyunga Kim,Seung-Hwa Lee

doi:10.1038/s41598-021-98026-4

Abstract

Myocardial injury after non-cardiac surgery (MINS) is a well-known and relevant indicator of early postoperative mortality, but factors related to increased mortality in MINS patients are as yet unknown. The Charlson Comorbidity Index (CCI) is widely used to classify various comorbid conditions and underlying diseases. Our study aimed to determine the prognostic value of CCI with regard to mortality of patients with MINS. This study comprises 5633 patients who had MINS as diagnosed by a rise of postoperative cardiac troponin I above the normal range (≥ 0.04 ng/mL) from January 2010 to June 2019. Patients were divided into two groups according to median weighted CCI score: low CCI (≤ 2) and high CCI (> 2) groups. The primary outcome was 30-day mortality after surgery, and secondary outcomes were 1-year and overall mortalities. Of the 5633 patients, 3428 (60.9%) were in the low CCI group (1.21 ± 0.84) and 2205 (39.1%) were in the high CCI group (4.17 ± 1.82). After propensity score matching, mortality during the first 30 days after surgery was significantly greater in the high CCI group than the low CCI group (9.4% vs. 6.0%, respectively; hazard ratio 1.56, 95% confidence interval 1.23–1.98, p < 0.001). A high CCI score was associated with increased 30-day mortality in patients with MINS, suggesting that the CCI may need to be considered when predicting outcomes of MINS patients.

Highlights

The presence of comorbid conditions is associated with reduced survival of patients in various clinical situations[1,2,3,4]
These patients were stratified into two groups according to median weighted Charlson Comorbidity Index (CCI) value: 3428 (60.9%) patients were allocated to the low CCI group and 2205 (39.1%) patients to the high CCI group
The high CCI group had a larger proportion of male, hypertension, arrhythmia, preoperative use of continuous renal replacement therapy, beta-blocker and direct oral anticoagulant use, high-risk surgeries according to ESC/ESA criteria, general anesthesia, longer operation duration, and continuous infusion of an inotropic agent or a red blood cell transfusion during surgery

Summary

Introduction

The presence of comorbid conditions is associated with reduced survival of patients in various clinical situations[1,2,3,4]. The Charlson Comorbidity Index (CCI) was introduced in 1987 to classify the severity of comorbid conditions[5] Since it has been validated as a reliable tool for predicting prognosis and has been updated with different weights for various d iseases[6,7]. The incidence of MINS for all non-cardiac surgeries has been estimated to be as high as 17.9%, and comorbidities such as hypertension, coronary artery disease, heart failure, prior myocardial infarction, and kidney disease significantly increase the risk of M INS12. It is unclear whether the effects of comorbidities extend to the short-term mortality of patients after MINS diagnosis. In this study, we used the CCI to grade the severity of comorbidities in MINS patients and evaluated the incidence of postoperative 30-day mortality

Methods

Results

Conclusion