Diabetic retinopathy in newly diagnosed Type 2 diabetes mellitus: Prevalence and predictors of progression; a national primary network study

Abstract

Aims: To determine, in real-world primary care settings, the prevalence of, and risk factors for, retinopathy at Type 2 diabetes mellitus diagnosis and report cumulative incidence and progression of retinopathy seven years after diabetes diagnosis. Methods: Retrospective cohort analysis of people with newly diagnosed Type 2 diabetes recorded by the Royal College of General Practitioners Research and Surveillance Centre (between 2005 and 2009, n=11,399). Outcomes included; retinopathy prevalence at diabetes diagnosis (baseline) and cumulative incidence or progression of retinopathy at seven years. Retinopathy prevalence was compared with the United Kingdom Prospective Diabetes Study (UKPDS-1998). Factors influencing retinopathy incidence and progression were analysed using logistic regression. Results: Baseline retinopathy prevalence was 18% (n=2,048) versus 37% in UKPDS. At seven years, 11.6% (n=237) of those with baseline retinopathy had progression of retinopathy. In those without baseline retinopathy, 46.4% (n=4,337/9,351) developed retinopathy by seven years. Retinopathy development (OR: 1.05 [95%CI: 1.02–1.07] per mmol/mol increase) and progression (OR: 1.05 [1.04–1.06]) at seven years was associated with higher HbA1cat diabetes diagnosis. Obesity (OR: 0.88 [0.79–0.98]) and high socioeconomic status (OR: 0.63 [0.53–0.74]) were negatively associated with retinopathy development at seven years. Conclusions: Baseline retinopathy prevalence has declined since UKPDS. Additionally, HbA1c at diabetes diagnosis remains important for retinopathy development and progression.