Cataract as a Cause of Visual Impairment: Epidemiology and Organization of Surgical Care (Based on Data of the Ural Eye and Medical Study)

Background: Today, cataract is one of the main causes of reversible blindness and visual disability. In health care, monitoring of cataract surgery rates is fundamental to achieving universal health coverage.

Objective: To assess the prevalence of visual impairment and blindness, cataract surgical coverage and prevalence, and the factors preventing timely surgical intervention for this disease.

Materials and methods: The cross-sectional clinical population Ural Eye and Medical Study conducted on the basis of the Ufa Eye Research Institute in 2015–2017, involved 5,899 people, including 3,400 rural (57.6 %) and 2,499 urban residents (42.4 %), of which 2,580 (43.7 %) and 3,319 (56.3 %) were men and women, respectively (mean age: 59.0 ± 10.7 years (range: 40–94 years). Data analysis was carried out using IBM SPSS Statistics (USA).

Results: We established that the prevalence of bilateral visual impairment in the population was 6.4 % (95 % CI: 6.85–7.07 %). The main causes of visual impairment were cataract (53.72 %), age-related macular degeneration (11.96 %), myopic degenerative maculopathy (3.46 %), diabetic retinopathy (3.46 %), and glaucomatous optic neuropathy (2.66 %). The prevalence of cataract surgery was 6.1 % (95 % CI: 4.0–9.3 %). Poor visual outcomes after cataract surgery were observed in 11.5 % of cases. The main reasons for low postoperative visual acuity included the refractive error (39.6 %), macular degeneration (19.0 %), glaucoma (15.5 %), posterior capsule opacification (13.8 %), and diabetic retinopathy (12.1 %). The cataract surgical coverage of patients with a decrease in visual acuity of the better-seeing eye to < 0.05; < 0.1 and ≤ 0.3 amounted to 77.5 %, 65.3 %, and 39.8 %, respectively. The factors preventing timely cataract surgery were poor awareness of patients about the need for surgical treatment (36.1 %), being very busy at work or at home (25.3 %), fear of the upcoming treatment (16.8 %), and concomitant somatic diseases (10.3 %).

Conclusion: The results of analyzing the prevalence of blindness and low vision caused by impaired transparency of the crystalline lens, outcomes of cataract surgery, and factors that impede timely surgical treatment in the study area, contribute to improvement of ophthalmology services and planning of surgical care programs to patients with these conditions.

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