Disease severity at diagnosis of OAG in Canada (Dr Yvonne Buys)

Yvonne Buys, MD, FRCSC

In this presentation, Dr Buys talks about the disease severity of open angle glaucoma at diagnosis time. Despite being a treatable condition, glaucoma is still a leading cause of blindness in Canada.

Our current evidence from the literature of the epidemiology in Canada is based on one population study published in 1966 using Schiotz tonometry and tonography; neither of which are used on a regular basis anymore as diagnostic tools. This repeats the finding presented earlier today of 3.9% prevalence in those not known to have glaucoma. Limitations of that study is that the diagnosis was based on self-reporting. We need to increase patient knowledge of disease and decrease asymptomatic glaucoma, hence the reason for the Canadian Glaucoma Risk Factor Study.

Canadian Glaucoma Risk Factor Study
Study Design

  • Multi-Centre non interventional
  • Used the Canadian Ophthalmological Society (COS) guidelines for classification of staging of disease
  • 405 pts enrolled, 113 with OH and 292 OAG; 50% presented with moderate or advanced disease
  • Primary goal was identifying risk factors and only consistent finding was that of increased age

Key findings

  • History of present or past smoking significantly increased risk of having glaucoma
  • 82% optometrist source of referral
  • More referrals from Ophthalmologists likely to have glaucoma vs those from optometrists

Importance of early diagnosis

  • improved outcomes
  • cost savings to health care system not to mention patient specific costs such as loss of work
  • current cost treatment $300M canada and can save $40M by treating earlier

Barriers to early diagnosis

  • access to care by de-listing routine eye exam
  • socioeconomic status
  • poor case finding
  • high cost of screening programs and more targeted screening based on risk factors.

Comment from audience

  • best kind of screening is concentrating on family members of those we see