Abstract
Purpose::
To find whether there is an association between a known diagnosis of diabetes and clinically confirmed glaucoma, detected at mobile eye screenings in San Antonio, Texas.
Methods::
Four-day screenings for glaucoma were held monthly at different sites using a 60-foot Lions Mobile Eye Screening Unit. Those screening positively, with at least 2 reproducible FDT misses in either eye, underwent HVF SITA 30-2 perimetry, HRT II scanning laser tomography, tonometry, and a full examination by an ophthalmologist. A glaucoma specialist reviewed all examination findings and rated the results as suspect, mild, moderate, or severe glaucoma. All participants underwent a pre-screening interview that specifically asked whether they had diabetes.
Results::
Among >6000 individuals (mean age 62) screened during the past 34 months in Bexar County, 657 (11%) reported having diabetes. Glaucoma was confirmed or suspected after clinical exam in 212 (4%) of all screenees (mean age 59). Among these 212 induviduals with confirmed/suspect glaucoma, 159 (75%) were Mexican-American, 64 (30%) of whom reported having diabetes. Diabetes was more prevalent among Mexican-American females (256; 39%) than males (197; 30%). Among each of the other ethnic groups screened, fewer than 7% of participants of either gender reported having diabetes. Among positively screened male Mexican-Americans with diabetes who were ultimately confirmed to have severe glaucoma, a very high proportion (39%) demonstrated severe glaucomatous pathology on clinical examination. Diabetic Mexican-American females screening positively for glaucoma more frequently displayed less severe pathology, with 32% being categorized as being glaucoma suspects only. Among the male African-Americans with confirmed/suspected glaucoma 9% reported being diabetic, and the proportion among African-American females was similar (8%). In no other ethnic group was diabetes reported among more than 4% of those whose positive screening exam resulted in confirmed or suspected glaucoma.
Conclusions::
The overall proportion of Mexican-Americans among the positive and negative screening cohorts was comparable, but there was a nearly three-fold difference observed in the proportion reporting diabetes among individuals with suspected or confirmed glaucoma versus adults who passed the eye screening (ie. Pinhole VA >20/40 and normal FDT OU). These findings suggest that diabetes, which is highly prevalent among Mexican-Americans, may be a risk factor for glaucoma among individuals of that heritage in Bexar County, where at least 95% of adult diabetes is Type II.
Keywords: diabetes • clinical (human) or epidemiologic studies: prevalence/incidence