Compliance of pharmacological treatment for non-ST-elevation acute coronary syndromes with contemporary guidelines: influence on outcomes.

Background: Although the proven efficacy of evidence-based therapy in patients with cardiovascular diseases, the recommendations are not always instituted. We aimed to analyse the compliance of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients with treatment guidelines and to assess the impact of these measures in hospital death during the index hospitalization.

Population And Methods: All consecutive patients (pts) included in the Portuguese Registry on Acute Coronary Syndromes (ProACS) between January 1, 2002 and August 31, 2011 were analysed. Compliance with Guidelines for the management of NSTE-ACS was evaluated with a 6-point therapeutic score (ThSc), comprising the treatment with: aspirin, clopidogrel, heparin, beta-blocker, angiotensin-converting enzyme inhibitor and statin. One point was assigned for each drug prescribed and zero if not given. The total therapeutic compliance was defined as ThSc =6 points.

Results: The final analysis comprised 14,276 pts (67.1% male; mean age 67.6±12.3 years), most of them admitted with non-ST elevation myocardial infarction (77.4%). The mean value of ThSc was 4.9±1.1 and total compliance occurred in 36.7% pts. Centres with percutaneous coronary intervention (PCI) capacity had a statistically significant higher ThSc (5.0±1.0 vs. 4.8±1.1, P<0.001) and were associated with higher total compliance [OR 1.53, 95% confidence intervals (CI), 1.42-1.65, P<0.001]. In-hospital mortality was 2.4% (354 deaths). Compared to pts who died, the survivors had a higher ThSc (4.9±1.1 vs. 4.2±1.3, P<0.001) and this score was independently associated with lower risk of in-hospital mortality (OR 0.70, 95% CI, 0.64-0.77, P<0.001). Receiver operating characteristics curve analysis showed a good accuracy of ThSc for the occurrence of in-hospital mortality with the area under the curve (AUC) 0.82 (95% CI, 0.80-0.84, P<0.001), sensitivity 71.6% and specificity 78.0%. Age, peripheral artery disease, Killip-Kimball class >I, electrocardiogram (ECG) with ST-segment depression and positive troponin were other independent predictors of in-hospital mortality.

Conclusions: In the present study, patients with NSTE-ACS who received medications recommended by guidelines had better in-hospital outcomes. These findings highlight the need to clarify the clinical recommendations and to develop approaches for quality improvement in this subset of patients.