A new analysis of Medicare records finds dramatic differences across the United States in rates of new glaucoma diagnoses, suggesting the eye disease is likely being overdiagnosed in some regions and underdiagnosed in others.
Looking at all Medicare claims for a seven-year period, the team found glaucoma rates had risen slightly overall, but that people in New England or the Mid-Atlantic states had about 30% higher odds than people in the Southeast of being diagnosed with glaucoma-and some 70% higher chances of being diagnosed with suspected glaucoma. The study published in Ophthalmology reports that potentially both physicians and patients in (predominantly rural) areas are not getting the healthcare that would be obtained in a large urban setting such as the New York-Baltimore-Philadelphia area. Lower diagnosis rates in less-urbanized settings may stem from different physician styles in examining patients and detecting glaucoma or fewer eye-care visits by patients, or both.
More than 2.2 million Americans are estimated to have glaucoma, which can lead to blindness. For the new study, researchers examined a random sample of Medicare claims submitted by ophthalmologists, optometrists, and outpatient surgery centers. They looked at claims data from 2002 through 2008, across nine large geographic regions and 179 subregions. The researchers report that the overall prevalence of diagnosed glaucoma increased from 10.4% in 2002 to 11.9% by 2008, largely owing to an increase in suspected open-angle glaucoma diagnoses (from 3.2% to 4.5%). The relative prevalence of diagnosed open-angle glaucoma compared with diagnosed angle-closure glaucoma was 32 to 1. Thuse, acute glaucoma was seriously underdiagnosed.
The New York City area had the highest rates of the condition of all the 179 subregions, which indicated that physicians there were either overdiagnosing it or doing a better job of detecting it. The low rates of diagnosis in all the other areas suggest its’ the latter.
Healthcare providers need to be performing gonioscopy on a regular basis. Women are more likely than men to have the condition and rates of most forms of the condition rose until age 80, and then fell thereafter. This may indicate lack of continuity in care among the very old. Only about 50% of the beneficiaries made an office visit to an optometrist or ophthalmologist in 2008. Blacks, Hispanics and Asians were less likely than non-Hispanic whites to have an eye exam, but they also showed the highest rates of glaucoma and greater risk of developing it.