Abstract
Purpose:
Age-related macular degeneration (AMD) causes 5% of global blindness and 1% of visual impairment. In Latin America, little research has been done on the disease. Argentina has one of the highest elderly populations in the region with up to 13.1% being 65 years or older. Despite its significantly aging population, there have been no studies to date on AMD in Argentina, where epidemiological studies on blindness suggest that AMD may be the cause of 3-4% of blindness. The purpose of this case-control study is to assess the risk factors for the development and progression of AMD in Argentina.
Methods:
Through email and telephone communications, 28 ophthalmologists from Buenos Aires City and 4 interior provinces surveyed patients on the possible risk factors of AMD. Surveys were used for patients’ antioxidant intake, age/gender, race, body mass index (BMI), hypertension, diabetes (and type of treatment), smoking, sunlight exposure, red meat consumption, fish consumption, and the presence of AMD. Ophthalmological examination composed of indirect ophthalmoscopy and Amsler grid was performed. Patients were classified according to the severity of AMD lesions. Patients presenting no signs of AMD were used as controls. Results were analyzed with main effects models for logistic regression and ordinal logistic regression.
Results:
There were 175 cases and 175 controls with a mean age of 75.4 years and 75.5 years, respectively, of whom 236 (67.4%) were female. One hundred and fifty-nine (45.4%) had AMD in their left eyes, 154 (44.0%) in their right eyes, and 138 (39.4%) in both eyes. Of the cases with AMD in their left eyes, 47.8% had the dry type, 40.3% had the wet type, and the type was unknown for 11.9%. The comparable figures for right eyes were: 51.9%, 34.4%, and 13.7%, respectively. The main effects model was dominated by higher sunlight exposure (OR [odds ratio]: 3.3) and a family history of AMD (OR: 4.3). Other factors included hypertension (OR: 2.1), smoking (OR: 2.2), and being of the Mestizo race, which lowered the risk of AMD (OR: 0.40). Red meat/fish consumption, BMI, and iris color did not have an effect. Higher age was associated with progression to more severe AMD.
Conclusions:
Sunlight exposure, family history of AMD, and an older age were the significant risk factors. There may be other variables, as the risk was not explained very well by the existing factors. A larger sample may produce different and better results.
Keywords: 412 age-related macular degeneration •
413 aging