Cognitive Impairment Is Associated with Medication Nonadherence in Asymptomatic Carotid Stenosis

Abstract Objective Adherence to medical management of vascular risk is vital for stroke prevention in patients with asymptomatic carotid stenosis. Because carotid disease is a risk factor for cognitive impairment, we sought to determine whether undiagnosed cognitive impairment affects medication adherence in this setting. Methods Sixty patients with asymptomatic ≥50% internal carotid artery stenosis without known dementia or stroke were screened for evidence of cognitive impairment using the Montreal Cognitive Assessment. Medication adherence was monitored using electronic pharmacy prescription refills. Medications studied included antiplatelet agents, statins, antihypertensives, and diabetes medications. Nonadherence was defined as a refill lag of ≥3 months during the 12 months before cognitive screening. Results Sixty percent of patients (36/60) had evidence of cognitive impairment (Montreal Cognitive Assessment P P  = .009). A trend toward decreased adherence to statins ( P  = .09) and antihypertensives ( P  = .06) was observed. Conclusions Medication adherence in patients with asymptomatic carotid stenosis is significantly reduced among those with undiagnosed cognitive impairment. Cognitive screening of asymptomatic patients with carotid stenosis identifies those who may benefit from increased supervision to improve medication adherence.