OAG patients may be at less risk of dementia. Photo: Sarah B. Klein, OD. Click image to enlarge.

Although studies have shown higher relative risk of dementia in some patients experiencing ocular diseases, most notably AMD, the opposite relationship was recently demonstrated in glaucoma patients. Researchers from UCLA and Greece’s University of Thessaloniki presented findings at ARVO 2023 in New Orleans of a large retrospective analysis of open-angle glaucoma (OAG) patients from 2019 California Medicare claims.

Subtypes of OAG included primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), pseudoexfoliative glaucoma and pigmentary glaucoma. From there, these OAG subtypes were analyzed for a diagnosis of either dementia or vascular dementia. There were many covariates influencing the results, including demographics of age, sex, race and ethnicity and systemic diseases of cardio- and cerebrovascular diseases, atrial fibrillation and flutter, diabetes, atherosclerosis and atheroembolism, hypertension and lipoprotein metabolism disorders. More specific covariates of depression, hearing loss, obesity, smoking-related disorders, alcohol-related disorders and long-term aspirin, anticoagulant and antithrombotic/antiplatelet use were identified as well. The researchers included analysis performed by age groups, split into three categories: 65 to 74, 75 to 84 and 85+.

A total of 2,431,150 Medicare recipients were included, with 4.3% (n=104,873) exhibiting POAG, 0.4% (n=9,199) that exhibited NTG, 0.2% (n=4,045) with pseudoexfoliative glaucoma and 0.05% (n=1,267) with pigmentary glaucoma. Diagnosis of either type of dementia had a prevalence of 3.2% (n=79,009). However, the likelihood of having any dementia was lower for all subtypes of OAG when compared with non-glaucomatous patients.

Looking at age analysis, pseudoexfoliative glaucoma revealed greater risk of vascular dementia in the youngest age cohort. Further, all OAG subtypes in the oldest age group displayed lower odds of having any dementia when compared with non-glaucomatous patients, but this was not seen in the youngest age group.

While this seems a relatively positive finding for OAG patients, the authors noted that instead, “These findings may suggest selection bias, with older adults who continue to follow-up with glaucoma care being more cognitively intact.” They concluded that “increased likelihood of vascular dementia in pseudoexfoliative glaucoma aligns with shared vascular pathology. Further studies are needed to better understand the complex relationship between glaucoma, dementia and their subtypes.”

Original abstract content © Association for Research in Vision and Ophthalmology 2023.