Title of article :
Distribution of Iris Colors and its Association with Ocular Disorder in the Tehran Eye Study
Author/Authors :
Hashemi, Hassan Noor Ophthalmology Research Center, Noor Eye Hospital , KhabazKhoob, Mehdi Noor Ophthalmology Research Center, Noor Eye Hospital , Yekta, AbbasAli Department of Optometry - Mashhad University of Medical Sciences , Mohammad, Kazem Department of Epidemiology and Biostatistics - School of Public Health - Tehran University of Medical Sciences , Fotouhi, Akbar Department of Epidemiology and Biostatistics - School of Public Health - Tehran University of Medical Sciences
Abstract :
Purpose: To determine the distribution of iris colors in the population of Tehran and to assess
possible associations between iris color and Ocular disorder
Methods: Through a stratified random cluster sampling approach, 160 clusters were selected in
different municipality districts of Tehran, and the approached households were invited to a clinic.
After the initial interview, all participants had complete eye examinations and their iris color was
categorized as grey/blue, yellow/green, light brown, medium brown, and dark. Distributions were
determined in percentages and possible correlations with race, refractive errors, visual impairment,
cataracts, age-related macular degeneration (AMD). Intraocular pressure (IOP) was also
examined.
Results: Out of 4230 participants aged 7 years or more, the iris color was determined in 4200
people; in 54.09% [95% confidence interval (CI) 51.74% to 56.44%] the iris color was medium
brown as the most prevalent color, and in 1.96% (95% CI: 1.43% to 2.48%) the color was grey/blue
as the least prevalent color. The inter-gender difference in iris color was not statistically significant
(P=0.288). AMD showed the highest prevalence in light brown iris colors (P<0.001). Nuclear
cataract and posterior subcapsular cataract (PSC) was significantly correlated with iris color, with
higher risks of cataract among medium brown, light brown and yellow/green iris colors (P<0.001).
Conclusion: The most prevalent iris color in the population of Tehran was medium brown. In light of
the observed correlation between the iris color and certain conditions such as cataract and AMD
with lighter eye colors, further studies are recommended to investigate the probable associations.
Keywords :
Cross-Sectional Study , Ocular Disorder , Iris Color
Journal title :
Astroparticle Physics