Exercise may be key factor in protecting against leading cause of sight loss

International glaucoma expert presents new research findings on impact of lifestyle on glaucoma risk at eye doctor’s conference

New breakthroughs in the battle against a leading cause of sight loss were presented by internationally renowned glaucoma specialist, Professor Jonathan Crowston at a conference of eye doctors in Ireland this week.

Addressing delegates at the Irish College of Ophthalmologists (ICO) Annual Conference at the Slieve Russell Hotel in Cavan today (Thursday May 18th) Professor Jonathan Crowston, Head of Ophthalmology at the University of Melbourne and Managing Director at the Centre for Eye Research in Australia (CERA) discussed new evidence from a novel study[1] relating to the impact of lifestyle on glaucoma risk. The findings of the recent mouse model study at CERA shows that exercise could be a key factor in the protection of cells that are affected by glaucoma which can lead to irreversible sight loss.

Glaucoma affects 2 per cent of Irish people over the age of 40 and 3.5 per cent over the age of 80. It is often referred to as the “silent thief of sight” as the condition is essentially symptomless in the early stages and attacks the peripheral vision, so is often only identified when significant vision loss has occurred.

Professor Crowston said,

“Glaucoma is a disease of the optic nerve, the part of the eye that carries the images we see to our brain and it causes the cables in the nerve to die off quicker than they should.   The main risk factors to developing glaucoma are ageing and a family history of the condition, but recent laboratory studies have shown that exercise can have a significant effect on the ability of retinal ganglion cells to recover.”   

“Our research is looking at new treatments to make the optic nerve more robust and our research indicates that exercise may play a key role in protecting this nerve.  Retinal ganglion cells (RGCs) become increasingly vulnerable to injury with advancing age.   While age has traditionally thought to be a non-modifiable risk factor for disease, emerging evidence suggests this may not be the case.  We recently showed that this vulnerability can be strongly modified in mice by exercise in the form of daily swimming.” 

The aim of the study at CERA, which runs laboratory and clinic-based research to understand why getting older pre-disposes individuals to developing glaucoma, was to investigate cellular changes associated with exercise-induced protection of aging retinal cells and the role of local and peripheral trophic signalling in mediating these effects. 

Professor Crowston said,

“We found that exercise protected RGCs against dysfunction and cell loss after an acute injury induced by elevation of intra-ocular pressure.  This age-related vulnerability was almost completely reversed by exercising mice for 5 weeks before and 7 days after injury.  The data provides compelling evidence that exercise can reverse negative impacts of aging in RGCs and modify their response to injury.”

Highlighting the importance of early detection of glaucoma, Professor Crowston said,

“Getting an eye test is crucial as 80-90% of sufferers have no easily recognisable symptoms.   For most types of glaucoma, you can have moderate to advanced disease and still not be aware you have it. The astounding fact is our brains are very good at filling in the picture, even when 80-90% of your visual field is lost.”

He added, “Every month I see patients in the advanced stages of the disease who are much harder to treat than the patients who are diagnosed early. You are at elevated risk if you have a family history or elevated eye pressure but effective treatments are available if caught early enough.

Attending the ICO conference, Ms Aoife Doyle, glaucoma specialist at the Royal Victoria Eye and Ear Hospital in Dublin said, “The ICO will continue to raise awareness and educate the public on the importance of looking after their eye health, especially in the advent of new treatments that can prevent unnecessary vision loss in patients.  Regular routine eye exams, and particularly for those in the higher risk categories, is so important.  Early diagnosis followed by careful regular observation and treatment means that damage can usually be kept to a minimum in patients, and vision stabilised.   However early detection is critical because sight that has been lost due to glaucoma cannot be recovered.”

Over 180 delegates from the Irish and International ophthalmic community are in attendance at the Irish College of Ophthalmologists Annual Conference this week to hear about the latest developments in eye health care, as well as advances in medicine, technology, research and treatments for patients with sight-threatening conditions.

 

ENDS

18th May 2017