The impact of African-Caribbean heritage on the development of sight threatening diabetic retinopathy in a multi-ethnic cohort of people with type 2 diabetes.

<p dir="ltr">Objective: Our aim was to identify risk factors for sight threatening diabetic retinopathy (STDR) in a multi-ethnic cohort of type 2 diabetes attending a surveillance digital diabetes eye screening service in South London between 2004 to 2018. </p><p dir="ltr">Research design and methods: 8529 people were included in this analysis, who had no retinopathy at baseline (49% female, 38% Caucasian, 43.4% African-Caribbean, 18.6% other). STDR was defined as the presence of any moderate to severe non-proliferative or pre-proliferative diabetic retinopathy or proliferative diabetic retinopathy or maculopathy in either eye as per United Kingdom National Diabetic Eye Screening criteria. Multivariable analyses with STDR as primary endpoint and death as competing event were performed. </p><p dir="ltr">Results: Of the 8529 people, 489 people (5.7%) progressed to STDR over median follow up of 8.9 years. They had higher baseline median (interquartile range) HbA1c 75.9 (58.4, 93.4) vs 61.7 (49.9, 79.2) mmol/mol and longer duration of diabetes 11 (7, 15) vs 4(2, 9) years and were more likely to be of African-Caribbean heritage (48 % vs 52 %), p<0.001 for all. Given that 2880 people died before progressing to STDR, we performed a competing risk analysis, in which, hazard ratio (95% confidence-intervals), African Caribbean ethnicity 1.35 (1.13-1.62), duration of diabetes 1.05 (1.05-1.06), HbA1c 1.02 (1.02-1.02) and total cholesterol 1.13 (1.05-1.21) emerged as significant independent factors associated with development of STDR. </p><p dir="ltr">Conclusions: In a multiethnic cohort of type 2 diabetes, we observed an increased risk of STDR in people of African-Caribbean ethnicity, which was independent of traditional risk factors. </p><p><br></p>