Background and purpose: Adherence to medication is often suboptimal after stroke and transient ischemic attack (TIA), which increases the risk of recurrent stroke and death. Complex interventions and motivational interviewing (MI) have been proven effective in other areas of medicine. The objective of this study was to investigate the effectiveness of a multifaceted intervention including MI in improving medication adherence for secondary stroke prevention.
Methods: In this randomized controlled trial, TIA and stroke patients receiving a pharmacist intervention in a hospital setting were compared with patients receiving usual care. The intervention consisted of a focused medication review, an MI-approached consultation and 3 follow-up telephone calls and lasted for 6 months. The primary outcome was a composite medication possession ratio (MPR) for antiplatelets, anticoagulants and statins in the year after hospitalization, assessed by analyzing pharmacy records and reported as both a continuous rate and a binary outcome. Secondary outcomes included composite MPRs at 3, 6 and 9 months as well as adherence and persistence to specific thrombopreventive medications at 12 months. Clinical outcomes included a combined end point of cardiovascular death, stroke or acute myocardial infarction. Patient satisfaction with the service was assessed for the intervention patients.
Results: The analyses included 102 intervention patients and 101 controls. At 12 months, the median MPRs (IQR) were 0.95 (0.77-1) in the intervention group and 0.91 (0.83-0.99) in the control group, and 28 and 21% of the patients, respectively, were nonadherent (MPR <0.80; risk difference: 7%; 95% CI: -5 to 19%). In both groups, the median MPR decreased over time. From 3 to 12 months, the MPR fell by 5% (p < 0.05) in the intervention group and by 9% (p < 0.05) in the control group, but between the groups, comparisons showed no statistically significant difference. No significant differences were found for adherence and persistence to specific thrombopreventive agents or for the clinical outcome. The intervention patients were satisfied with the service; about half of them reported increased knowledge about medication, and one third reported increased confidence with medication use. Pharmacists identified drug-related problems in one third of the patients.
Conclusions: A multifaceted pharmacist intervention including MI did not improve adherence or persistence to secondary stroke prevention therapy and had no impact on clinical outcomes. However, due to the high adherence rates, only little room for improvement existed. Future studies should focus on patients at high risk of nonadherence and include outcomes more sensitive to the impact of behavioral interventions.
Keywords: Ischemic attack, transient; Medication adherence; Motivational interviewing; Pharmacy services, hospital; Stroke.