By Adrian Galbreth
The chances of developing a vision-threatening disease that can lead to glaucoma and cataracts are affected by environmental factors, a new study has found.
According to experts at the Massachusetts Eye and Ear's Glaucoma Center of Excellence, the risk of developing exfoliation syndrome (ES) - an eye condition that is a leading cause of secondary open-angle glaucoma and increased risk of cataract as well as cataract surgery complications - is influenced by age, gender and where people live.
Researchers set out to find out how demographic and geographic risk factors are associated with ES, using data from 78,955 women in the Nurses' Health Study (NHS) and 41,191 men in the Health Professionals Follow-up Study (HPFS) residing throughout the continental United States.
These were followed for 20 years or more and provided lifetime residence information to examine the descriptive epidemiologic features of ES or exfoliation glaucoma suspect (EGS).
According to Dr Louis Pasquale, study co-author and director of the facility, the study confirmed established associations with age and family history and exfoliation glaucoma or exfoliation glaucoma suspect (EG/EGS), as well as providing new data on associations with gender, eye colour and ancestry.
The study also showed an increased risk in women, but it was unclear as to whether gender-specific differences in the eye, such as axial length differences or environmental factors related to lifestyle, account for why they are more at risk for this disease.
He said the report demonstrates that there is a positive association between latitude and ES risk that is robust and not related to demographic features or other systemic covariates.
"Another manuscript we published recently suggests that lower ambient temperature interacts with increased solar exposure to increase the risk of ES," Dr Pasquale added.
"This new work demonstrates a relation between increasing latitude and a condition with a strong predisposition to glaucoma."
He said that more work is needed to determine how environmental factors conspire to contribute to ES.
by Martin Burns