Normal-tension glaucoma has been linked to an increased risk of cognitive impairment and possibly dementia, Australian researchers report today.
The authors of the research, which is published in the latest edition of the British Journal of Ophthalmology, say their findings suggest the condition could share similar neurodegenerative pathways with dementia and build on previous studies that have linked primary open angle glaucoma, which encompasses low-tension glaucoma or normal-tension glaucoma (NTG) and high-tension glaucoma (HTG), and dementia.
NTG is more common in Asia, while high-tension glaucoma is more common in Europe and investigators from Flinders University, Adelaide, wanted to establish if it is linked to cognitive impairment and dementia among people with Asian ethnicity.
They accessed the Australian and New Zealand Registry of Advanced Glaucoma and randomly selected 248 patients, all above the age of 65, who had NTG. These were matched by age and sex with 349 patients with HTG.
All patients were invited to participate in a health questionnaire and cognitive assessment over the telephone. In total, 290 patients – 144 with NTG and 146 with HTG – had the cognitive screen and there was found to be no difference between the two groups in demographic and eye parameters at baseline.
Cognitive impairment was more than twice as prevalent in NTG patients with than it was in those with HTG.
Although this is an observational study and cannot establish cause, the authors write: “Our finding of an association between normal-tension glaucoma and cognitive impairment supports a growing body of evidence suggesting an association between normal-tension glaucoma and dementia.”
Mullany S, Xiao L, Qassim A et al. Normal-tension glaucoma is associated with cognitive impairment. British Journal of Ophthalmology 30 March 2021; doi:10.1136/bjophthalmol-2020-317461
Leave a Reply