Risk of New Indications for Anticoagulants and Thrombolytics in People With Cognitive Impairment: Implications for Anti-Amyloid Therapy.

OBJECTIVES: Anticoagulants and thrombolytics may interact with anti-amyloid monoclonal antibodies (mAbs) to increase intracranial hemorrhage risk, so expert guidance recommends against their co-prescription. We aimed to estimate how many people with mild cognitive impairment (MCI) or dementia develop a new cardiovascular indication for anticoagulant and thrombolytic drugs.

METHODS: In a longitudinal cohort of adults aged 65 years or older from the Health and Retirement Study (2010-2020) with linked Medicare claims and no previous indication for anticoagulants, cognition was categorized as normal, MCI, or dementia. We fit separate Fine-Gray survival models accounting for competing risk of death to estimate 1-year incidence of atrial fibrillation (AF), deep vein thrombosis (DVT), pulmonary embolism (PE), acute myocardial infarction (AMI), and stroke.

RESULTS: Among 12,373 participants (mean age 73 years, 59% female), the 1-year risk in those with MCI was 1.7% for AF, 1.2% for DVT, 0.4% for PE, 1.2% for AMI, 2.0% for stroke, and 5.7% for any indication. In those with dementia, the 1-year risk was 1.7% for AF, 1.8% for DVT, 0.3% for PE, 1.0% for AMI, 2.4% for stroke, and 6.7% for any indication.

DISCUSSION: Our findings inform shared decision making about the tradeoffs of anti-amyloid mAbs but should be validated in populations with confirmed treatment eligibility.