Delay in filling first clopidogrel prescription after coronary stenting is associated with an increased risk of death and myocardial infarction

Abstract

Background-Patients frequently experience difficulties with medication compliance after hospital discharge. We investigated the effect of a delay in filling a first clopidogrel prescription after hospital discharge on clinical outcomes subsequent to coronary stenting. Methods and Results-Hospital administrative, community pharmacy, and cardiac revascularization data were determined for all patients receiving a coronary stent in British Columbia 2004-2006 with follow-up out to 2 years. Cox's proportional hazard regression analysis, adjusting for baseline demographics and procedural variables, was performed to examine the effects of delay in filling a clopidogrel prescription after hospital discharge on clinical outcomes. Of 15 629 patients treated with coronary stents, 3599 received at least 1 drug-eluting stent (DES), whereas 12 030 received bare metal stents (BMS) alone. In total, 1064 (30%) and 3758 (31%) patients in the DES and BMS groups, respectively, failed to fill a prescription within 3 days of discharge (median, 1 day; interquartile range [IQR], 1 to 3). After regression analysis, a delay of > 3 days was predictive of mortality and recurrent myocardial infarction (MI) irrespective of stent type (DES: hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.7 to 3.4; and HR, 2.0; 95% CI, 1.5 to 2.7, respectively, and BMS: HR, 2.2; 95% CI, 1.9 to 2.6; and HR, 1.8; 95% CI, 1.5 to 2.1, respectively). This excess hazard was greatest in the 30-day period immediately after hospital discharge (mortality: HR, 5.5; 95% CI, 3.5 to 8.6; and MI: HR, 3.1; 95% CI, 2.4 to 4.0, for all patients). Conclusions-Delays in patients filling their first prescription for clopidogrel after coronary stenting are common and associated with adverse clinical outcomes, irrespective of stent type. Strategies to reduce delays have the potential to improve clinical outcomes.