impact of carpet weaving on refractive errors

purpose : to determine the effect of carpet weaving on refractive errors methods : in this cross sectional study, carpet weavers and non-weavers in the normal population of mashhad were regarded as exposed and non-exposed groups, respectively. a carpet weaver was a person who wove carpets 7 hours a day for at least 2 years. the non-weavers group was selected from the population of mashhad through stratified cluster sampling. the variables of age, gender, education, with respect to their frequency, were matched between the two groups. results : in this study, 266 carpet weavers (exposed individuals) and 549 non-weavers group (non-exposed individuals) were evaluated. the prevalence of myopia was 78.9% in carpet weavers and 19.0% in non-weavers [odds ratio (or)=16.03, 95% confidence interval (ci)=11.13-23.09]. the prevalence of hyperopia was 6.02% in carpet weavers, and 56.75% in non-weaver group (or=0.05, p<0.001). the prevalence of astigmatism was 39.47% in carpet weavers and 21.46% in non-weavers. the odds of against-the-rule (atr) astigmatism was 1.72 times more in carpet weavers as compared to non-weavers (p<0.001). conclusion : the results of this study showed that carpet weaving had a strong correlation with myopia. in addition to myopia, the prevalence of astigmatism, specially atr astigmatism, was higher in carpet weavers.    iranian journal of ophthalmology 201123(4):29-36 © 2011 by the iranian society of ophthalmology