ABSTRACT
Purpose: to evaluate the prevalence of cataract, lens opacity, and other conditions of the lens among residents of Tehran aged 40 or above, Tehran-Iran
Methods: this study was performed as a part of the population based study on the prevalence of glaucoma among citizens older than 40 in Tehran. A total of 2 160 participants joined the study [50% response rate]. After performing a medical history interview, all participants were examined according to a standard protocol including refraction, visual acuity testing, and slit-lamp biomicroscopy of the anterior segment. Cataract was diagnosed as any lens opacity with visual acuity of 20140 or less in the absence of other causes of visual loss
Results: the prevalence of lens opacity among right eyes, left eyes, and overall was 29.4%, 30.6%, and 32.4%, respectively. Prevalence of cataract was 8.1% in right and 9.1% in left eyes, respectively. The overall prevalence of cataract was 12%. The rate of pseudophakia or aphakia was 3.9% in right or left eyes and 5.2% overall. The prevalence of cataract in male and female subjects was 14.3% and 10.6%, respectively. The prevalence of cataract among adults older than 50 [17.1%] was 9 times that of the 40-49 age group [1.9%]. The prevalence of lens opacity among males and females was 39.1% and 28.3%, respectively. The prevalence of lens opacity among adults older than 50 [45.7%] was more than 7 times that of the 40-49 age group [6.3%]. The prevalence of grade II lens opacification or over was 33.4%. The most frequent type of lens opacity was nuclear sclerosis followed by cortical and posterior subcapsular opacities
Conclusion: the prevalence of cataract and lens opacity in residents of Tehran aged 40 or over is significant especially among elderly indivisuals and it may be estimated that 240,000 persons in Tehran population have cataract and 648,000 have lens opacity, which is a matter of concern for our health system