THE IMPACT OF MYOPIA ON THE DEVELOPMENT OF CATARACT – PRELIMINARY REPORT.

To investigate the effect of myopia on the process of the lens opacity and the development of cataract.

Department of Ophthalmology, Faculty of Medical Sciences in Katowice, Medical University of Silesia in Katowice, Katowice, Poland

Department of Ophthalmology, Kornel Gibiński University Clinical Center, Medical University of Silesia in Katowice, Katowice, Poland

The study included patients qualified for cataract surgery. Group 1 consisted of participants with myopia (confirmed by autorefractometry at least 4 years before the onset of cataract - spherical equivalent (SE) ≤ -1 D), divided into three subgroups: low (≥ -3,5 D SE ≤ -1 D); medium (≥ -6 D SE < -3,5 D); high (SE < -6 D) myopia. Group 2 included normo-sighted (> -1 D SE < +1 D) and hyperopic (SE ≥ +1 D) patients age and gender matched for group 1. People with factors that have a documented effect on the acceleration of cataract development were excluded from the study. Participants underwent a comprehensive ophthalmic examination including measurement of refraction, the axial length of the eyeball, assessment of lens opacities using the Lens Opacities Classification System III. A questionnaire was used to collect medical history and background check.

Both groups included 100 eyes (119 women and 81 men), mean age of patients was 72 ± 8.1 SD (ranging from 45 to 86 years old). Average SE among myopic patients was - 4,65 ± 2,2 SD          (up to - 24,25 D) and in group 2 amount to +1,44 ± 1,7 SD (maximum + 9,0 D). Nuclear cataract was the most common distinct subtype (36,7%). There was a statistically significant association between myopia, especially high, and incident nuclear and posterior subcapsular (PSC) cataract, after adjustment for multiple confounders and severity of nuclear opacity. Moreover, smoking, exposure to sunlight as well as iris atrophy contribute to development of lens opacity.

These epidemiologic data provide that compared to emmetropia, myopia is associated with increased risk of nuclear and PSC cataract subtypes. Improved understanding of risk factors for cataract would help to identify high-risk groups and personalize the diagnostic and therapeutic path.