One third of patients who were discharged after a PCI failed to fill their clopidogrel prescriptions within three days, according to a study published online May 28 in Journal of the American Heart Association, at the risk of serious consequences. Findings showed that the time following hospital release to the filling of the prescription dramatically influences outcomes.

Utilizing The Cardiac Services BC Registry and Pharmanet from 2004 through 2006, patents in British Columbia were followed over two years after discharge from a PCI. Of 15,629 coronary stent implantations followed, 3,599 involved drug-eluting stents and 12,030 bare-metal stents.

These two groups were monitored to see how long it took for prescriptions to be filled and then their resulting outcomes were plotted. Thirty percent of the drug-eluting stent group and 31 percent of the bare metal stent group failed to fill their prescription within three days of discharge.

Of those who took more than three days to fill their prescription, the outcomes at two years were poor. Ten percent of the drug-eluting stent cohort and 15 percent of the bare metal stent cohort died. The drug-eluting stent group and the bare metal stent group saw 9 percent and 10 percent, respectively, readmitted with recurrent MI.

Twenty-two percent of the bare metal stent cohort and 18 percent of the drug-eluting stent cohort had a combined endpoint of all-cause mortality. These percentages were at a significant increase to those seen by the members of each cohort who took three days or less to fill their prescription, whether drug-eluting or bare metal, of less than 10 percent for any one or combined outcome.  

Patients who waited to fill their prescription had an approximately three times greater risk for re-hospitalization for MI or death in the days that followed in both the short and long term. This risk did not decrease dramatically over time, although the risk was highest in the first 30 days.

Findings held regardless of whether the stent implanted was bare metal or drug eluting. More than the type of stent, the issue appeared to be medication adherence.

“Almost one in three patients failed to fill a community prescription for clopidogrel within three days of hospital discharge,” Nicholas L. Cruden, MBChB, PhD of the Royal Infirmary of Edinburgh, and the team wrote. “This coincides with a period immediately after hospital discharge when patients often experience difficulties with medication compliance, the most common issue being failure or a delay to fill a discharge prescription.”

This failure had serious implications on treatment and outcomes, highlighting the need to ensure medication adherence. Cruden et al recommended, “Identifying strategies to avoid delays in obtaining a first community prescription for clopidogrel may lead to improved clinical outcomes in this population.”