Is aspirin (acetylsalicylic acid) recommended for patients with vascular dementia?

Aspirin for Vascular Dementia

Aspirin is not recommended for patients with vascular dementia unless they have established atherosclerotic cardiovascular disease (ASCVD) requiring secondary prevention. The risk of serious bleeding complications outweighs any potential cognitive benefit in this population. 1, 2

Evidence Against Aspirin Use in Vascular Dementia

The Canadian Consensus Conference explicitly recommends against aspirin for patients with mild cognitive impairment or dementia who have brain imaging evidence of covert white matter lesions of presumed vascular origin but no history of stroke or brain infarcts. 1 This recommendation is particularly relevant for vascular dementia patients without documented cardiovascular events.

The landmark AD2000 trial provides the strongest direct evidence: In 310 patients with Alzheimer's disease (including 18 with concomitant vascular dementia) followed for 3 years, aspirin 75 mg daily showed no cognitive benefit (mean MMSE score difference of only 0.10 points, 95% CI -0.37 to 0.57; p=0.7) and no functional benefit (mean BADLS score difference of -0.62 points, 95% CI -1.37 to 0.13; p=0.11). 2 Critically, aspirin increased serious bleeding requiring hospitalization (8% vs 1%, relative risk 4.4,95% CI 1.5-12.8; p=0.007), including three fatal cerebral hemorrhages in the aspirin group. 2

A comprehensive Cochrane review (2020) analyzing multiple trials confirmed no evidence supporting aspirin or other NSAIDs for dementia prevention, with clear evidence of harm. 3 The ASPREE trial of 19,114 elderly participants showed aspirin increased major bleeding (RR 1.37,95% CI 1.17 to 1.60) and mortality (RR 1.14,95% CI 1.01 to 1.28) without reducing dementia incidence (RR 0.98,95% CI 0.83 to 1.15). 3

When Aspirin IS Indicated

Aspirin 75-162 mg daily should be used only for secondary prevention in vascular dementia patients with documented ASCVD, including: 4, 1

• Prior myocardial infarction
• Prior stroke or transient ischemic attack
• Documented coronary artery disease
• Peripheral arterial disease with revascularization
• Other established atherosclerotic disease

For these patients, the cardiovascular benefit of aspirin far outweighs bleeding risk, and aspirin remains strongly recommended. 4

Age-Related Considerations

Patients over age 70 years without established cardiovascular disease face greater risk than benefit from aspirin therapy. 4, 1 This is particularly relevant for vascular dementia patients, who are typically elderly and at higher baseline bleeding risk due to age-related factors including cerebral amyloid angiopathy. 2

Clinical Decision Algorithm

For vascular dementia patients:

1. Does the patient have documented ASCVD (prior MI, stroke, coronary disease, PAD)?

   • YES: Use aspirin 75-162 mg daily for secondary prevention 4, 1
   • NO: Proceed to step 2

2. Is the patient over age 70 years?

   • YES: Do not use aspirin (bleeding risk exceeds any potential benefit) 4, 1
   • NO: Proceed to step 3

3. Does the patient have diabetes with multiple cardiovascular risk factors AND low bleeding risk?

   • YES: Consider aspirin only after shared decision-making, weighing cardiovascular benefits against bleeding risk 4
   • NO: Do not use aspirin 1

Common Pitfalls to Avoid

Do not prescribe aspirin based solely on vascular dementia diagnosis or white matter changes on imaging. 1 The presence of cerebrovascular disease on neuroimaging does not constitute an indication for aspirin in the absence of clinical cardiovascular events. 1

Do not assume aspirin will slow cognitive decline. Despite biological plausibility, high-quality RCTs consistently show no cognitive benefit. 2, 3 Observational studies suggesting benefit from low-dose aspirin (75-100 mg) 5 are contradicted by RCTs, which represent higher-quality evidence. 3

Recognize increased bleeding risk in dementia patients: The AD2000 trial showed an 8% hospitalization rate for serious bleeding over 3 years with aspirin versus 1% without, including fatal cerebral hemorrhages. 2 Elderly patients with dementia may have additional bleeding risk from falls, concurrent medications, and unrecognized peptic ulcer disease. 4, 2

Alternative Risk Reduction Strategies

For vascular dementia patients without established ASCVD, focus on: 4, 6

• Optimal blood pressure control (target <130/80 mmHg) 6
• Statin therapy if dyslipidemia present 6
• Diabetes management with agents showing cardiovascular benefit (SGLT2 inhibitors, GLP-1 receptor agonists) 4
• Lifestyle modifications including diet, exercise, and smoking cessation 6