Ocular haemodynamics in children with vitamin D deficiency.

Background: To evaluate the retinal and optic nerve head microvasculature in children with vitamin D deficiency using optical coherence tomography angiography (OCTA).

Methods: This prospective, cross-sectional study included 74 eyes of 37 children with vitamin D deficiency (Group I) and 64 eyes of 32 healthy children (Group II). All participants underwent OCTA examinations. Foveal retinal thickness (FRT), peripapillary retinal nerve fibre layer (RNFL) thickness, vessel density (VD) in different sections of the retina, and optic disc were analysed and compared between the groups.

Results: The mean ages, gender, mean intraocular pressures, and central corneal thickness levels were similar between the groups. The mean vitamin D levels measured from the venous blood samples of the participants were 11.42 ± 4.94 ng/mL in Group I and 26.03 ± 11.08 ng/mL in Group II, and the difference between these values was statistically significant (P < 0.001). There was no significant difference regarding optic disc capillary densities between the groups. However, compared with the Group II, Group I showed significantly higher values of FRT, and lower values of superficial whole, parafoveal and perifoveal VD (287.58 ± 12.43 mm vs 258.21 ± 22.68, P < 0.001, 50.85 ± 2.15% vs 51.77 ± 2.30%, P = 0.01, 54.05 ± 2.83% vs 55.18 ± 2.40%, P = 0.01, 51.27 ± 2.21% vs 52.11 ± 2.27%, P = 0.03, respectively). The vitamin D levels showed significantly negative correlation with FRT values in Group I (r = -0.439, P = 0.001).

Conclusions: Vitamin D deficiency seems to be associated with higher values of FRT and decreased levels of superficial VD. Retinal microvascular architecture may be affected in paediatric subjects who have vitamin D deficiency.