Thrombolysis in myocardial infarction (TIMI) risk score validation in Saudi Arabia

Abstract

BACKGROUND: Early risk stratification plays a pivotal role in the optimal management of non-ST segment elevation myocardial infarction/unstable angina (NSTEMI/UA) acute coronary syndromes and certainly improving patients care and their final outcomes. Thrombolysis in myocardial infarction (TIMI) risk score was developed from randomized clinical trials on patients with NSTEMI and UA, and it has been validated in non-selected Western patient populations. OBJECTIVE: The aim of the present study was to assess the validity of TIMI risk score on NSTEMI and UA patients in King Abdulaziz Medical City, Jeddah, Saudi Arabia. METHODS: This cross-sectional study was undertaken on 194 patients diagnosed with NSTEMI or UA. They were consecutively included over a two-year period. Data were collected from medical records, TIMI score was calculated and 30 days outcome was recorded. Model discrimination and calibration was tested in the overall enrolled population. RESULTS: Validity of TIMI score in predicting in hospital mortality within 30 days of diagnosis of NSTEMI or UA in Saudi population was assessed by ROC curve and binary logistic regression analysis. The accuracy of discrimination of the TIMI risk score was poor; the area under the ROC curve (AUC) or C-index was 0.612 (95% CI: 0.539 to 0.681). Binary logistic regression model revealed good calibration or model fit of TIMI risk score as revealed by the Hosmer and Lemes how test for the constructed logistic model; p value was 0.934 (>0.05) denoting good model fit. CONCLUSION: The generalizability of this single-center study requires further confirmation in a larger sample population allowing stratification of the study participants into different subgroups according to known important risk factors such as diabetes mellitus, renal failure, or age, so that the performance of the TIMI risk score could be comprehensively assessed before deciding its application in our population.