Patterns of use and effectiveness of early invasive strategy in non-ST-segment elevation acute coronary syndromes: an assessment by propensity score.

BACKGROUND: The patterns of use and the benefit of an early invasive strategy (EIS) in patients with non-ST-segment elevation acute coronary syndrome in a real-life population are not well established.
METHODS: All consecutive patients hospitalized because of non-ST-segment elevation acute coronary syndrome between November 2004 and June 2005 in 32 randomly selected hospitals were prospectively included. Patients were stratified by their baseline risk profile using the Global Registry of Acute Coronary Events (GRACE) risk score in 2 groups. Inhospital mortality and 1- and 6-month mortality or rehospitalization for acute coronary syndromes were analyzed. To ensure optimal adjustment propensity score, conventional logistic regression and Cox regression were used.
RESULTS: Of 2,856 patients analyzed, 1,616 (56%) had low/intermediate risk (GRACE<or=140) and 1,240 had high risk (GRACE>140). Patients who underwent EIS had lower risk than those who did not (GRACE score 128.2+/-41 vs 138.5+/-43, P<.001). Coronary angiography facility emerged as the strongest predictor of EIS (odds ratio [OR] 13.7 [95% CI 7.1-25]). Patients who underwent EIS had lower rate of the 6-month outcome in both the whole population (9% [95% CI 6.6-11.9] vs 14% [95% CI 12.5-15.6], P=.003) and in high-risk patients (16.5% [95% CI 11-23] vs 23.6% [95% CI 20.8-26.5], P=.04). However, this benefit of EIS was not apparent after statistical adjustment in the whole population (OR 0.8, CI 0.55-1.1, P=.17) or in high-risk patients (OR 0.7, CI 0.46-1.1, P=.16).
CONCLUSIONS: In a real-life population, EIS was mainly performed in patients of low/intermediate risk. An obvious benefit of this strategy could not be found.