Treatment adherence in patients without ST-elevation acute coronary syndrome.

Abstract

Background: Despite progress during the last decades, patients with coronary artery disease (CAD) remain with a high residual risk due to multiple reasons. Optimal medical treatment (OMT) provides a decrease of recurrent ischemic events after acute coronary syndrome (ACS). Therefore, treatment adherence results crucial to reduce further outcomes after the index event. No recent data are available in Argentinian population; the main objective of our study was to evaluate the adherence at 6 and 15 months in post non-ST elevation acute coronary syndrome (NST-ACS) consecutive patients. Secondary objective was to evaluate the relationship of adherence with 15-month events.

Methods: A prespecified sub-analysis in the prospective registry Buenos Aires I was performed. The adherence was evaluated using the modified Morisky-Green Scale.

Results: A number of 872 patients had information about adherence profile. Of them 76.4% were classified as adherents at month 6 and 83.6% at 15 (P=0.06). We did not find any difference in baseline characteristic between the adherent and non-adherent patients at 6 months. The adjusted analysis showed that non-adherent patients had a rate of ischemic events at 15^th month of 20% (27/135) vs. 11.5% (52/452) in adherent patients (P=0.001). The bleeding events defined were of 3.6% in the non-adherent group vs. 5% in the adherent group without a statistical difference (P=0.238).

Conclusions: Adherence to treatment is still a major issue as almost 25% of patients should be considered as non-adherent to OMT. No clinical predictor of this phenomenon was identified but our criteria were not exhaustive. Good adherence to treatment was highly associated to a reduction of ischemic events, whereas no impact on bleeding events was found. These data support a better network and collaboration with shared decision between healthcare professionals with patients and family members to improve acceptance and adherence to optimal medical strategies.