Delays in Filling Clopidogrel Prescription Associated with Increased Major Adverse Events Following PCI
In prior studies, up to 1 in 5 patients prescribed clopidogrel at hospital discharge following percutaneous coronary intervention (PCI) delayed filling the prescription, and this delay was associated with adverse outcomes. However, it is unknown whether delays in filling clopidogrel prescriptions after PCI are common in a large healthcare system with an integrated inpatient and outpatient pharmacy system such as VA. Thus, this retrospective cohort study assessed the frequency of delays in filling the initial clopidogrel prescription after hospital discharge for Veterans (n=8,382) who underwent PCI with stent implantation between 1/05 and 9/10 at any of 60 VA hospitals. Data for this study were obtained from the national VA Clinical Assessment, Reporting, and Tracking (CART) Program. Veterans who did not fill a clopidogrel prescription on the day of discharge were considered to have a delay. To avoid inclusion of patients receiving medications outside the VA system, patients who filled their initial prescription more than 30 days after discharge were excluded. The primary outcome was the occurrence of a major adverse event, defined as myocardial infarction (MI) or death within 90 days of hospital discharge.
- Approximately 1 in 14 Veterans delayed filling clopidogrel prescriptions after PCI. Moreover, delays were associated with increased risk of major adverse events; specifically, patients with a delay in filling their clopidogrel prescription more often suffered MI (12% vs. 6%) and death (2.2% vs. 1.5%) compared to those without delay.
- The percentage of Veterans with delays varied by VA hospital, ranging from 0% to nearly 44%. This large variation suggests a need to identify best practices that allow hospitals to optimize prescription filling at discharge to potentially improve patient outcomes.
- In the VA healthcare system, delayed filling of clopidogrel prescription occurred less than half as often in a prior study conducted with a Medicare population, which found that 20% of patients delayed filling their clopidogrel prescription after hospital discharge. Therefore, it is possible that the lower rate of delayed prescription filling within VA (7%) may be attributable to greater coordination of care, since inpatient and outpatient prescriptions are managed by a single VA pharmacy service.
- This analysis did not include patient socioeconomic factors.
- Investigators did not record events occurring outside the VA system except when VA paid for care.
Drs. Maddox and Ho are with HSR&D's Center for Innovation for Veteran-Centered and Value-Driven Care in Denver, and Drs. Maddox, Rumsfeld, and Ho are part of VA/HSR&D's Ischemic Heart Disease Quality Enhancement Research Initiative (QUERI).
Byrd J, Maddox T, O’Donnell C, Grunwald G, Bhatt D, Tsai T, Rumsfeld J, and Ho M. Clopidogrel Prescription Filling Delays and Cardiovascular Outcomes in a Pharmacy System Integrating Inpatient and Outpatient Care: Insights from the VA CART Program. American Heart Journal. September 2014;168(3):340-345.