Long-term use of antiplatelet drugs by stroke patients: a follow-up study based on prescription register data European Journal of Clinical Pharmacology, 05/23/2012

Ostergaard K et al. – Long–term non–persistence with antiplatelet treatment was high and more pronounced in the patients with less severe stroke. The findings on the use of acetylsalicylic acid (ASA) and dipyridamole indicate that non–persistence may in part be amenable to simple intervention measures.

• Population–based prescription register data were used to determine antiplatelet drug use in a cohort of stroke patients discharged from a Danish neurology department.
• The antiplatelet drugs comprised acetylsalicylic acid (ASA), clopidogrel and dipyridamole (if combined with ASA use).
• Non–persistence was defined as failure to present a prescription for antiplatelet drugs within 180 days after the dosage of a previous prescription had run out, or within 180 days after discharge.
• Cox regression was used to identify risk factors for non–persistence.

• The cohort comprised 503 patients with ischaemic stroke discharged in 1999–2001.
• During follow–up (median 2.8 years, interquartile range 0.8–7.8 years), 486 of the subjects presented prescriptions for antiplatelets.
• Most subjects used a dual regimen of ASA and dipyridamole (N=320).
• Of 110 non–persistent subjects in this group, 64 stopped using ASA, but continued to use dipyridamole in monotherapy.
• Overall, 181 patients (36 %) were non–persistent.
• Stroke severity was inversely associated with the risk of non–persistence [NIHSS score on admission 0–3 (reference); 4–6: hazard risk (HR) 0.87, 95 % confidence interval (CI) 0.61–1.25; 7+: HR 0.47, 95 % CI 0.29–0.74].