Aims: There is little information on clinical risk stratification (CRS) compared to objective risk tools in patients with non-ST elevation acute coronary syndromes (NSTEACS). We quantified CRS use, its agreement with Global Registry of Acute Coronary Events (GRACE) risk scores (GRS), and association with outcomes.
Methods and results: Data were extracted from the Australian Cooperative National Registry of Acute Coronary Care, Guideline Adherence and Clinical Events (CONCORDANCE), a multi-centre NSTEACS registry. From February 2009 to December 2015, 4512 patients from 41 sites were included. Predictors of CRS use and association with treatment were identified, CRS-GRS agreement determined and prediction of in-hospital and 6-month mortality compared. Clinical risk stratification was documented in 21% of patients. Family history of coronary disease was the only independent predictor of CRS use [odds ratio (OR) 1.23, 95% confidence interval (95% CI) 1.04-1.45]; electrocardiogram changes (OR 0.8, 95% CI 0.68-0.96), elevated biomarkers (OR 0.59, 95% CI 0.48-0.73), dementia (OR 0.56, 95% CI 0.36-0.84), and an urban hospital setting (OR 0.41, 95% CI 0.19-0.89) were independent negative predictors. A treatment-risk paradox was observed: high CRS risk patients received less anticoagulation (79% vs. 88%, P = 0.001) and angiography (83% vs. 71%, P < 0.001). CRS-GRS agreement was poor (kappa coefficient = 0.034) and CRS less predictive for in-hospital (c-statistic 0.54 vs. 0.87, P < 0.001) and 6-month (c-statistic 0.55 vs. 0.74, P < 0.01) mortality.
Conclusion: In Australia, CRS does not guide treatment, correlate with GRS or predict outcomes. This study suggests the need for greater awareness and integration of validated tools such as the GRACE score to optimally direct treatment and potentially improve outcomes.