Risk factors for primary open-angle glaucoma in Filipinos
Patricia M. Khu, MD, MS, Edgardo U. Dorotheo, MD, Ma. Margarita L. Lat-Luna, MD, Antonina T. Sta Romana
Objective
This study determined the risk factors for primary open-angle glaucoma
(POAG) among Filipinos.
Methods
This is a case-control study of POAG cases and controls recruited from the
University of the Philippines-Philippine General Hospital (UP-PGH). All
underwent a comprehensive eye examination consisting of best-corrected
visual acuity, applanation tonometry, slitlamp biomicroscopy, gonioscopy,
fundus evaluation, automated perimetry, optic-disc photography, and a
standardized questionnaire interview of medical history and family history of
glaucoma and other systemic diseases. Visual-field results and optic-disc photos
were graded by 2 glaucoma experts as to the presence or absence of
glaucomatous optic neuropathy. Risk factors studied were subjected to multiple
logistic regression.
Results
A total of 365 participants (164 males, 201 females), mean age of 58.7 years,
were subdivided into 193 controls (no glaucoma) and 172 POAG cases. The
participants with glaucoma were older, had poorer visual acuity, larger optic
cupping, and worse global indices in the visual field. Those 60 years and over
had an increased risk of POAG. There was a threefold increased association
with POAG for each unit decrease in visual acuity. Enlarged vertical cupping
of the optic disc (0.7 or greater) showed 5 times increased risk of developing
POAG. There was a 29% and 45% increased risk for POAG for every decibel
increase in mean defect and pattern standard deviation respectively. Of the
systemic diseases studied, including family history of major medical conditions,
only family history of hypertension was strongly associated with POAG, with
2.5 odds of increased association with glaucoma.
Conclusion
The causes of POAG are multiple and complex. Older age, poorer visual
acuity, large vertical disc cupping, worse visual-field global indices, and family
history of hypertension were associated with POAG in this study.
Keywords: Primary open-angle glaucoma, Risk factors, Optic-disc cupping, Visual field, Visual
acuity