A large South Korean cohort study reports that patients with retinal vein occlusion (RVO) may be at an increased risk of all-cause dementia, Alzheimer’s disease and vascular dementia.

The investigation, published in the American Journal of Ophthalmology, also found people with both RVO and hypertension were at a higher risk of dementia.

The study used data from the South Korean National Health Insurance Service of participants aged 40 and older who underwent health examinations between 2009 and 2010. The RVO group was comprised of 46,259 patients who were initially diagnosed between 2006 and 2010. The comparison group included 138,777 individuals (three per RVO patient) matched according to age, sex and systolic blood pressure.

During a follow-up of about seven years, the study found 14,727 cases of dementia. Additionally, incidence probabilities for all types of dementia were significantly increased in the RVO group vs. the control group. The RVO group also showed increased risks of subsequent all-cause dementia (with a hazard ratio of 1.16), Alzheimer’s disease (1.15) and vascular dementia (1.24) relative to the comparison group.

Also of note: the presence of RVO was significantly associated with increased risks of all three types of dementia both in hypertensive and non-hypertensive individuals.

Retinal vascular change has been associated with changes in the brains of patients with dementia; however, there is limited evidence regarding the relationship between RVO and dementia risk, the researchers said.