The use of antiplatelet agents for secondary prevention of ischemic stroke in U.S. ambulatory care settings.

Introduction: We examined stroke prevention with antiplatelet agents by U.S. nonfederal office physicians and hospital outpatient departments from 2005-2006.

Methods: The nationally representative dataset used a multistage (112 primary sampling units, physicians/ hospitals, patient medical records) random sample of 1,702 visits by patients 20 years or older with cerebrovascular disease (national estimate: 15.4 million annual visits). Dependent variable: use of antiplatelet agents for patients without contraindications.

Independent Variables: age, sex, race/ethnicity, payment, primary care provider, prior visits in last year, comorbidities. Logistic regression was used to investigate associations with recommended interventions.

Results: Antiplatelet agents were prescribed at 31.1% of visits. Positive predictors: seeing the patient's primary care provider and having five or more comorbidities. Negative predictors: non-Hispanic Black race/ethnicity and having six or more prior visits in the last year.

Conclusion: Variations by visit characteristics suggest that improvement in using antiplatelet agents is possible, especially for non-Hispanic Black patients.