Rapid Assessment of Avoidable Blindness and Diabetic Retinopathy in Gilan Province, Iran

ABSTRACT

Purpose: To conduct an assessment of avoidable blindness and diabetic retinopathy (DR) in Gilan, 2014.

Methods: A cross-sectional population-based survey was performed on a representative sample of urban and rural individuals aged ≥50 years of the province. Blindness was defined as presenting visual acuity (PVA) <3/60 in the better eye. Moderate visual impairment (MVI) and severe visual impairment (SVI) were defined as 6/60 ≤ PVA <6/18 and 3/60 ≤ PVA <6/60 in the better eye, respectively. Diabetes mellitus (DM) was determined based on random blood sugar (RBS) levels ≥200 mg/dL or a previous diagnosis. We used the Scottish grading system to grade DR.

Results: We invited 2975 individuals from 85 clusters. Age- and sex-adjusted prevalence and 95% confidence interval (CI) of blindness, SVI, MVI, and DM in 2587 participants (response rate: 86.9%) were 1.5% (95% CI: 1.1–2.0), 1.5% (95% CI: 0.9–2.0), 11.3% (95% CI: 9.9–12.7) and 21.4% (95% CI: 19.2–23.7), respectively. The leading causes of blindness were cataract (47.1%), age-related macular degeneration (14.7%) and DR (8.8%). Cataract surgery (CS) coverage was 69.3%. The main challenges for CS were cost and unawareness. The outcome of CS was good in 66.9% of operated eyes. Any DR and/or maculopathy were observed in 25.3% (95% CI: 21.0–29.5) of subjects including 12.6% (95% CI: 9.7–15.6) sight-threatening DR. In previously known DM cases, 215 (41.7%) had never undergone an eye examination for DR.

Conclusion: The proportion of avoidable blindness and DR is considerable in Gilan Province.

KEYWORDS:

• Diabetic retinopathy
• Gilan Province
• Iran
• Rapid Assessment of Avoidable Blindness

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the writing and content of this article.

Funding

Financial support for this study was received from (1) Shahid Beheshti University of Medical Sciences, Tehran, Iran, and (2) Guilan University of Medical Sciences, Rasht, Iran.

Additional information

Funding

Financial support for this study was received from (1) Shahid Beheshti University of Medical Sciences, Tehran, Iran, and (2) Guilan University of Medical Sciences, Rasht, Iran.