Associations Between Retinal Artery/Vein Occlusions and Risk of Vascular Dementia.

BACKGROUND

Vascular disease is a risk factor for Alzheimer's disease (AD) and related dementia in older adults. Retinal artery/vein occlusion (RAVO) is an ophthalmic complication of systemic vascular pathology. Whether there are associations between RAVO and dementia risk is unknown.

OBJECTIVE

To determine whether RAVOs are associated with an increased risk of developing vascular dementia or AD.

METHODS

Data from Adult Changes in Thought (ACT) study participants were analyzed. This prospective, population-based cohort study followed older adults (age ≥65 years) who were dementia-free at enrollment for development of vascular dementia or AD based on research criteria. RAVO diagnoses were extracted from electronic medical records. Cox-regression survival analyses were stratified by APOEɛ4 genotype and adjusted for demographic and clinical factors.

RESULTS

On review of 41,216 person-years (4,743 participants), 266 (5.6%) experienced RAVO. APOEɛ4 carriers who developed RAVO had greater than four-fold higher risk for developing vascular dementia (Hazard Ratio [HR] 4.54, 95% Confidence Interval [CI] 1.86, 11.10, p = 0.001). When including other cerebrovascular disease (history of carotid endarterectomy or transient ischemic attack) in the model, the risk was three-fold higher (HR 3.06, 95% CI 1.23, 7.62). No other conditions evaluated in the secondary analyses were found to confound this relationship. There was no effect in non-APOEɛ4 carriers (HR 1.03, 95% CI 0.37, 2.80). There were no significant associations between RAVO and AD in either APOE group.

CONCLUSION

Older dementia-free patients who present with RAVO and carry the APOEɛ4 allele appear to be at higher risk for vascular dementia.