The Role of the Primary Care Physician in Diagnosing Glaucoma

The diagnosis of glaucoma brings about a sense of dread and almost immediately stimulates visions of complete blindness. And for good reason It is one of the leading causes of irreversible blindness worldwide. However glaucoma is treatable and does not need to lead to blindness in most cases. With appropriate treatment, glaucoma patients are likely to keep their vision or at least slow the progression of the disease and live relatively normal lives.

The key, like most disease processes, is early detection and treatment. Except for acute angle closure glaucoma (ACG), glaucoma is largely a “silent” disease with few symptoms or signs before it has reached an advanced stage. As such, the PCP has a critical role in screening and referring patients to the ophthalmologist as part of their overall health care.

According to the Glaucoma Research Foundation it is important to check certain patient regularly for glaucoma. Below is the recommended frequency in which your patients should have their eyes tested:

  • before age 40, every two to four years
  • from age 40 to age 54, every one to three years
  • from age 55 to 64, every one to two years
  • after age 65, every six to 12 months

Anyone with high risk factors should be tested every year or two after age 35

The easiest way to test for Glaucoma in your office is with the Diaton Tonometer.  This is the only Glaucoma detection device that allows you to test a patient over the eyelid.  Therefore requiring no anesthesia and less discomfort for your patients.

Click Here to see a Video Demonstration of this Glaucoma Pen 


Primary Open Angle Glaucoma (POAG) – It is estimated that 45 million people have OAG worldwide. Glaucoma
(combined OAG and ACG) is the second leading cause of blindness worldwide (8.4 million people). In the US, the prevalence of POAG in adults over the age of 40 is 2%. It is estimated that in 2010 there were 2.2 million people in the U.S. with glaucoma and that with the aging population,
this number will increase to 3.3 million by 2020.

In the U.S. the prevalence of glaucoma in African Americans is three to four times greater than
in Whites. It is the leading cause of blindness in African Americans. Hispanics and Latinos have similar prevalence rates as African Americans. Glaucoma is a more “aggressive” in Blacks where it tends to occur at an earlier age and is more refractory to treatment.11 Hyper-vigilance is warranted in screening African Americans and Hispanics.

Risk Factors for Glaucoma

Below is a listing of some of the accepted risk factors for glaucoma:

  • Intraocular Pressure (IOP): For every 1mmHg rise risk increased 10%
  • Central Corneal Thickness (CCT): The thinner (especially <550 microns) the greater risk; African Americans tend to have thinner corneas
  • Optic Disc Cupping: Increased (vertical >horizontal) cup-disc ratio
  • Diabetes Mellitus (DM): It remains controversial as to whether DM is associated with an increased risk of developing glaucoma
  • Hypertension (HTN): Acute hypertension increases the risk of glaucoma while chronic HTN is less clearly associated with an increased risk of developing glaucoma
  • Race: African Americans are much more likely to have POAG and rarely, have PACG (but when present in African Americans is much more likely to be chronic); Inuits and Asians are more likely to have PACG
  • Age: Ocular Hypertension Treatment Study (OHTS) showed increased risk of POAG with age per decade of 22-43% (in the univariate and multivariate analyses, respectively);  PACG is rare < 40 years old but prevalence increases each decade thereafter.
  • Gender: PCAG is 2-4 times more common in women than in men
  • Family History: First degree relative with POAG increases risk up to 13%;5,45 First degree relative with
  • PACG risk is different among racial groups with 1-12% prevalence in Whites and > 6 times risk in Chinese patients with any family history
  • Refraction Error: Myopia (nearsightedness) risk factor for POAG; Hyperopia (farsightedness) = risk factor for PACG