Aims/hypothesis: The aim of this study was to estimate the prevalence of and risk factors for diabetic retinopathy in newly diagnosed type 2 diabetes in general practices in the UK.
Methods: The Disease Analyzer Database (UK) assembles longitudinal data on diagnoses, prescriptions and laboratory values reported from 674 office-based physicians (97 general practices). Patients with newly diagnosed type 2 diabetes (between 2005 and 2009) were identified and the presence of retinopathy was defined based on the International Classification of Diseases code (E11.3) or on the original diagnosis text. The time period between first diabetes diagnosis and first retinopathy diagnosis was calculated. Logistic regression was used to examine associations of potential risk factors with prevalent diabetic retinopathy.
Results: There were 12,524 patients with newly diagnosed type 2 diabetes mellitus in the general practices. The mean age was 65 years with slightly more male patients (56%). The prevalence of diagnosed retinopathy was 19.0% (95% CI 18.3%, 19.7%). The median time to first retinopathy diagnosis was 309 (interquartile range 50-693) days. Factors independently associated with retinopathy in multivariate logistic regression were age (OR 1.02 [95% CI 1.01, 1.03] per year of age), male sex (OR 1.11 [95% CI 1.01, 1.22]), HbA(1c) (OR 1.12 [95% CI 1.02, 1.22] per 1% [11 mmol/mol] increase), systolic blood pressure (OR 1.03 [95% CI 1.01, 1.05] per 10 units) and antihypertensive drugs. No significant relationships were observed for obesity and diastolic blood pressure.
Conclusions/interpretation: Diabetic retinopathy was diagnosed in about one out of five patients with type 2 diabetes during the first year after diabetes diagnosis in UK general practices. Age, male sex, hyperglycaemia and hypertension were identified as risk factors of early retinopathy in type 2 diabetes.