Three-Year Follow-Up Study Investigating Changes in Retinal Vascular Morphology and the Relationship with Diabetic Retinopathy in Children with Type 1 Diabetes Mellitus

<b><i>Introduction:</i></b> This study aimed to investigate changes in retinal microvascular morphology and associated factors, and their relationship with diabetic retinopathy (DR) in children with type 1 diabetes mellitus (T1DM). <b><i>Methods:</i></b> Thirty-eight children enrolled in this 3-year follow-up study underwent complete ophthalmic examinations including fundus photography. Retinal vascular parameters were measured automatically and compared between baseline and follow-up. Multiple linear regression was used to investigate factors affecting changes in vascular parameters. Binary logistic regression was used to analyze the relationship between retinal microvascular morphology and DR. <b><i>Results:</i></b> The caliber of all retinal vessels (within 1–1.5 papillary diameter [PD] from the center of the optic disc, <i>p</i> = 0.030; 1.5–2 PD, <i>p</i> = 0.003), arterioles, and venules (1.5–2 PD, <i>p</i> = 0.001) was narrower in nearly all regions in the follow-up group compared with the baseline group. Vascular tortuosity increased in the central part of the retina and decreased in the periphery. The density (1–1.5 PD, <i>p</i> = 0.030) and fractal dimension (<i>p</i> = 0.037) of retinal vessels were increased at the end of the follow-up compared with baseline. Retinal vascular caliber was independently correlated with DR (odds ratio 0.793 [95% confidence interval 0.633–0.993]; <i>p</i> = 0.044). <b><i>Conclusion:</i></b> Retinal microvascular morphology in children with T1DM varied with the disease course. Narrower retinal vessels may be an independent risk factor for DR. Results of this study emphasized the importance of regular follow-up of fundus vascular morphology for the detection of early DR in children with T1DM.