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Published on: October 23, 2020
Visual impairment certification due to diabetic retinopathy in North and Eastern Devon
Siying Lin1, Bhaskar Gupta2, Natalee James3
1Torbay Hospital, Torbay and South Devon NHS Foundation Trust, Torquay, UK.
Purpose:
To determine certifications of visual impairment (CVIs) due to diabetic retinopathy (DR) in a region that has operated diabetic screening since 1992.
Methods:
A retrospective review of all CVIs due to DR was conducted, with mid-year population estimates and a diabetes prevalence model used to determine the annual incidence of certification from 2010 to 2013. For 2013, CVIs due to DR were also compared to all CVIs in the region.
Results:
The total number of certifications due to DR was 75; 52 were sight impaired (SI) and 23 severely sight impaired (SSI) certifications; 25% of patients had type 1, and 75% had type 2 diabetes mellitus. The mean age at time of CVI was 65.5 years. The mean duration of known diabetes was 22.0 years. The incidence of CVI due to DR ranged from 30.8 to 77.4 per million population per year between 2010 and 2013. The incidence of CVI in the diabetic population was estimated at 0.47 to 1.21 per 1000 patients per year with diabetes for 2010-2013. In 2013, DR was a main or contributing cause in 4.3% of all CVIs, but did not contribute to any SSI certifications in the working age population.
Conclusion:
The incidence of CVI due to DR was comparable to that reported in other regions. Nationwide, DR was the second most common cause of blindness in working age adults, but did not contribute to any SSI certifications in our population. Our results are consistent with the success of a long-standing retinal screening programme.
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