Albumin creatinine index added to the grace score increases its discriminative capacity for mortality at 12 years of follow-up in patients with acute coronary syndrome
Authors: Jorge Sebastian Castro Ortega J C , Claudio Higa C H , Fedor Novo F N , Maria Gambarte M G , Sol Donato S D , Rocio Montoya R M 
Published: October 2024

Abstract

introduction
There is currently no information on the prognostic value of the GRACE score with the additional addition of the albumin-creatinine index (ABI) for the prediction of very long-term mortality in unselected populations of acute coronary syndromes (ACS).

Objectives
To evaluate the additive value of the albumin-creatinine index in spontaneous urine sample to the GRACE score for the prediction of 12-year mortality from all causes in an unselected cohort of patients with acute coronary syndrome.

Material and methods
A prospective cohort study was carried out, which included patients admitted to a Community Hospital with a diagnosis of ACS. These patients had their IAC measured in a single spontaneous urine sample based on the principle of immunoturbidimetry in the first 24 hours of admission. The end point of the analysis was all-cause mortality at follow-up. The GRACE 2.0 score was calculated for all patients in the study. The scores were compared according to the following metrics: their power to discriminate between events and non-events (ROC Areas), calibration or goodness of fit, evaluating the agreement between the proportion of events and non-events expected by both scores observed by Hosmer Lemeshow Test. The comparison between the areas under the ROC Curves was carried out using De Long's test with the MEDCALC program version 19.1.7. The net reclassification index and its 95% CI (GRACE score + IAC/GRACE score) were evaluated.

Results
600 patients with ACS were analyzed, with an average age of 64 years. The GRACE score risk subgroups were divided by the established cut-off values: low risk (0 to 108), intermediate (109 to 139) and high risk (greater than 139). The area under the curve of the Grace score for mortality during follow-up was 0.79 (95% CI 0.69-0.89), while the area under the ROC curve of the GRACE + IAC score was 0.81 (95% CI 0.74-0.87). ). Comparing the two areas by the De Long test, the difference was statistically significant (P &lt; 0.0001; 95% CI 0.07- 0.015).
On the other hand, contingency tables were developed and the Hosmer Lemeshow Test (goodness of fit) was performed on the GRACE score and the GRACE + IAC score, observing agreement between expected events and non-events, throughout all subgroups of risk. In addition, reclassifications were made into deceased and survivors by applying the GRACE + IAC score on the GRACE score. The net reclassification rate was 28% (95% CI 21-35). The chi square of its Mc Nemar Test was 3.69 p &lt; 0.0002. The absolute comprehensive discriminatory improvement was 0.01 (95% CI 0.009-0.02) and the corresponding relative value was 8.2% (95% CI 7.9-8.5).

Conclusions
In this unselected ACS cohort, the albumin-creatinine index added to the GRACE score significantly increases its ability to discriminate mortality from all causes in a 12-year follow-up.Comparison between ROC curvesHosmer Lemeshow test