Diagnosed diabetic retinopathy in France, Italy, Spain, and the United Kingdom

The objective of this study was to describe the proportion and characteristics of patients diagnosed with diabetic retinopathy (DR) in France, Italy, Spain, and the United Kingdom (UK).

To estimate the proportion of patients with type 1 and type 2 diabetes diagnosed with DR, we conducted a cross-sectional survey of general practitioners in each country using physician records. In addition, diabetes specialists were recruited in Italy and Spain. We extracted data from the medical notes of a sample of DR patients to characterize DR severity and clinical characteristics.

The average number of physicians per country was 41 (range: 34-49). The proportion of diagnosed DR ranged from 10.3% (95% CI, 6.7-14.0%) in Spain to 19.6% (95% CI, 16.0-23.1%) in the UK. Of 752 DR patients studied, 53.9% were male; mean age (+/-SD) was 64.2+/-12.8 years. Consistently across countries, mild non-proliferative DR was the most common severity level of diagnosed DR. Proliferative DR (PDR) ranged from 19.7% (France) to 31.5% (UK). Diabetic macular oedema was reported in approximately 10% of patients. Hypertension (73.1%), dyslipidemia (63.2%), and neuropathy (52.1%) were the most common co-morbidities.

Country-specific prevalence of diagnosed DR may reflect clinical management of diabetes, healthcare systems, or record-keeping accuracy. Across countries, up to 30% of DR patients had a diagnosis of PDR, which could suggest that patients are diagnosed only when their disease is advanced.