Vitamin D deficiency is not associated with changes in retinal geometric parameters in young people with type 1 diabetes.
Changes in retinal geometric parameters predict risk and progression of diabetic retinopathy (DR). We have shown that vitamin D deficiency (VDD) is associated with DR. We hypothesized that VDD mediates changes in retinal geometric parameters. Retinal vascular geometric parameters were assessed using a semiautomated computer program in photographs from young people with type 1 diabetes (T1D) (n = 481) and summarized as central retinal arteriolar and venular equivalents (CRAE, CRVE), fractal dimension, length-diameter ratio, branching angle and curvature tortuosity. Parameters were compared between those with and without DR and VDD (25-hydroxyvitamin D concentration ≤ 50 nmol/L). Retinal vascular geometric parameters were also compared across quartiles of vitamin D levels. Median CRVE was higher in patients with DR compared with those without (median (IQR) CRVE 247.3  μ m (31.3) versus 238.8  μ m (23.5), P = 0.01). Fractal dimension was marginally greater in patients without VDD (1.49 (0.06) versus 1.47 (0.07) P = 0.03). There was no difference in CRAE, CRVE, length-diameter ratio, branching angle, and curvature tortuosity between those with and without VDD and across quartiles of 25OHD. In conclusion, DR is associated with higher CRVE in young people with T1D; however, VDD is not associated with changes in retinal vascular geometric measures, suggesting an earlier role in the time course of DR pathogenesis.
Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW 2145, Australia. myra.poon@health.nsw.gov.au
Myra
M
Poon
Maria E
ME
Craig
Harleen
H
Kaur
Janine
J
Cusumano
Muhammad Bayu
MB
Sasongko
Tien Yin
TY
Wong
Kim C
KC
Donaghue
D000293:Adolescent; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000473:pathology* / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000150:complications / Q000473:pathology* / Q000503:physiopathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D012160:Retina / Q000473:pathology* / Q000503:physiopathology; D012161:Retinal Artery / Q000473:pathology / Q000503:physiopathology; D012169:Retinal Vein / Q000473:pathology / Q000503:physiopathology; D014807:Vitamin D / Q000031:analogs & derivatives; D014808:Vitamin D Deficiency / Q000150:complications / Q000473:pathology* / Q000503:physiopathology
D014807:Vitamin D; C104450:25-hydroxyvitamin D