Glaucoma can result in gradual and permanent vision loss and ultimately blindness, if not diagnosed and treated. Globally, glaucoma is the leading cause of irreversible blindness. It is estimated to affect more than 400,000 Canadians, and the direct costs of vision loss from glaucoma in Canada are estimated at $300 million annually.
Age is a strong risk factor for glaucoma; people over age 60 are six times more likely to develop glaucoma. The burden of disease is growing as the Ontario population ages: between 2009/10 and 2015/16, the number of optometry and ophthalmology visits in Ontario for people with glaucoma increased by 34% and 67%, respectively (data source: IntelliHealth Ontario, Medical Services).
Although there is no cure for glaucoma, its progression can be managed, and there are significant opportunities to improve the quality of life of people with glaucoma through the delivery of high-quality care. Glaucoma develops painlessly and gradually; symptoms are often not apparent until there is substantial irreversible damage to the optic nerve fibres. As a result, glaucoma often goes undetected: it is estimated that up to 50% of people with glaucoma are not aware they have the disease. In a Canadian study, nearly half of people with newly diagnosed open-angle glaucoma had moderate or advanced disease at the time of diagnosis.
Early detection and treatment of glaucoma can often delay or prevent further vision loss. The best way to detect glaucoma is through a routine eye examination by an eye care provider.
In Ontario, there are inequities in access to care for some populations that are at risk for glaucoma. Lower socioeconomic status and older age are associated with a greater severity of glaucoma at the time of initial diagnosis, potentially because of delayed access to care. People aged 20 to 64 years old with a specific medical condition affecting the eye (including glaucoma, diabetes mellitus, cataract, retinal disease, amblyopia, visual field defects, corneal disease, strabismus, recurrent uveitis, and optic pathway disease) are eligible to receive OHIP coverage for a routine eye examination once every 12 months and for any follow-up appointments related to the condition. However, other people in this age group—including those at risk for glaucoma—must either pay out of pocket for the examination if performed by an optometrist or have their costs covered by private insurance (when available). The costs associated with routine eye examinations can be a barrier to access.
Administrative data reveal regional variations across Ontario in the use of glaucoma-related services; these may suggest inequities in access. In 2015/16, the rate of optometry visits for people with glaucoma ranged from 107 to 350 visits per 10,000 residents across Ontario’s 14 regions (data source: IntelliHealth Ontario, Medical Services), while the rate of consultations to an ophthalmologist (requested by an optometrist or a physician) varied across the regions, from 39 to 106 consultations per 10,000 residents (data source: IntelliHealth Ontario, Medical Services). Data also suggest there are variations in the procedures provided to people with glaucoma across regions. For example, rates of laser trabeculoplasty per 100,000 residents in 2015/16 ranged from 5.0 to 98.9 across the regions (data source: IntelliHealth Ontario, Medical Services).
Because administrative data currently available in Ontario have significant limitations both for identifying people with glaucoma and for capturing the use of certain glaucoma-related services (such as optometrist consultations that are not publicly insured), it is not known whether these regional variations in use are related to regional differences in the underlying prevalence of glaucoma, differences in service patterns, or true inequities in access to care.