Patterns of Use and Discontinuation of Secondary Prevention Medications After Stroke
Lachlan L. Dalli, Joosup Kim, Amanda G. Thrift, Nadine E. Andrew, Frank Sanfilippo, Derrick Lopez, Rohan Grimley, Natasha A. Lannin, Lillian Wong, Richard I. Lindley, Bruce Campbell, Craig S. Anderson, Dominique A. Cadilhac, Monique F. Kilkenny
Abstract
OBJECTIVE: To investigate whether certain patient, acute care, or primary care factors are associated with medication initiation and discontinuation in the community after stroke or TIA. METHODS: This is a retrospective cohort study using prospective data on adult patients with first-ever acute stroke/TIA from the Australian Stroke Clinical Registry (April 2010 to June 2014), linked with nationwide medication dispensing and Medicare claims data. Medication users were those with ≥1 dispensing in the year postdischarge. Discontinuation was assessed among medication users and defined as having no medication supply for ≥90 days in the year postdischarge. Multivariable competing risks regression, accounting for death during the observation period, was conducted to investigate factors associated with time to medication discontinuation. RESULTS: Among 17,980 registry patients with stroke/TIA, 91.4% were linked to administrative datasets. Of these, 9,817 adults with first-ever stroke/TIA were included (45.4% female, 47.6% aged ≥75 years, and 11.4% intracerebral hemorrhage). While most patients received secondary prevention medications (79.3% antihypertensive, 81.8% antithrombotic, and 82.7% lipid-lowering medication), between one-fifth and one-third discontinued treatment over the subsequent year postdischarge (20.9% antihypertensive, 34.1% antithrombotic, and 28.5% lipid-lowering medications). Prescription at hospital discharge (sub-hazard ratio [SHR] 0.70; 95% confidence interval [CI] 0.62-0.79), quarterly contact with a primary care physician (SHR 0.62; 95% CI 0.57-0.67), and prescription by a specialist physician (SHR 0.87; 95% CI 0.77-0.98) were all inversely associated with antihypertensive discontinuation. CONCLUSIONS: Patterns of use of secondary prevention medications after stroke/TIA are not optimal, with many survivors discontinuing treatment within 1 year postdischarge. Improving postdischarge care for patients with stroke/TIA is needed to minimize unwarranted discontinuation.