Subclinical atherosclerosis associates with diabetic retinopathy incidence: a prospective study

Background The prospective correlation between subclinical atherosclerosis and diabetic retinopathy (DR) incidence in Chinese patients with type 2 diabetes mellitus (T2DM) remains elusive. Methods Prospective data were obtained from 2781 patients with diabetes, among whom 1,964 and 2,180 T2DM patients without any and referable DR at baseline, respectively, were included in the analysis. Multivariate analyses were performed using the Cox proportional hazards model. Results Over a median follow-up of 22.2 months (interquartile range 12.7–27.7), 282 (14.36%) and 125 (5.73%) patients developed any and referable DR, respectively. After adjustment for confounders, each standard deviation (SD) increase in brachial-ankle pulse wave velocity (ba-PWV) was associated with 31% (95% confidence interval 1.15–1.50) and 38% (1.14–1.66) higher risks of incident any and referable DR, respectively. Compared with the lowest ba-PWV quartile, the highest ba-PWV quartile had 135% (1.48–3.72) and 293% (1.83–8.44) higher risks of developing any and referable DR, respectively. Per SD increase of pulse pressure (PP) was associated with 22% (1.09–1.38) and 22% (1.02–1.46) higher risks of incident any and referable DR, respectively. The restricted cubic spline models further indicated a significant linear association of baseline subclinical atherosclerosis with referable DR, and a nonlinear association with any DR. In addition, adding the ba-PWV to the prognostic model for DR incidence improved the C-statistic value, the integrated discrimination improvement value, and the net reclassification improvement value (all P < 0.05). Conclusions Baseline subclinical atherosclerosis was significantly associated with an increased risk of DR incidence, and elevated ba-PWV independently predicted incident DR in T2DM patients.