Stroke and transient ischemic attacks related to antiplatelet or warfarin interruption

Abstract

ABSTRACT Patients on anticoagulant or antiplatelet therapy are often required to discontinue these medications before and during surgical or invasive procedures. In some cases, the patient stops the treatment without medical supervision. These situations may increase stroke risk. Objective To identify the ischemic stroke and transient ischemic attack (TIA) prevalence related to length of time of discontinuation of antiplatelet or vitamin K antagonist therapy, in a group of inpatients from a specialized neurological hospital in Brazil. Methods Cross-sectional, retrospective and descriptive study of stroke inpatients for three years. Medical reports were reviewed to find study participants, stroke characteristics, risk factors, reasons and time of drug interruption. Results In three years, there were 360 stroke and TIA inpatients, of whom 27 (7.5%) had a history of antiplatelet or vitamin K antagonist interruption correlated with the time of the event (81% ischemic stroke, 19% TIA). The median time between antiplatelet interruption and an ischemic event was five days, and 62% of events occurred within seven days after drug suspension. For vitamin K antagonists, the average time to the ischemic event was 10.4 days (SD = 5.7), and in 67% of patients, the time between drug discontinuation and the event was 7-14 days. The most frequent reason for drug suspension was patient negligence (37%), followed by planned surgery or invasive examination (26%) and side effects, including hemorrhage (18.5%). Conclusion Antiplatelet or vitamin K antagonist suspension has a temporal relationship with the occurrence of stroke and TIA. Since these events are preventable, it is crucial that healthcare professionals convince their patients that drug withdrawal can cause serious consequences.

Keywords

• Stroke
• ischemic attack, transient
• anticoagulants
• compliance