Early change of retinal nerve fiber layer in children with type 1 diabetes mellitus in northern China

Objectives: This study aimed to identify discrepancies in the retinal nerve fiber layer (RNFL) between type 1 diabetes mellitus (T1DM) children without retinopathy and healthy subjects in northern China. Methods: This was a cross-sectional hospital-based study carried out from Jan 2019 until Jul 2021 at the department of pediatrics in Tianjin medical university general hospital. Children with T1DM but no retinal disease were screened. RNFL thickness was obtained via spectral domain optical coherence tomography. Disease duration, HbA1c, 25-hydroxyvitamin D level, insulin regimen, and diet control status were also collected. Results: A total of 20 children with T1DM and 20 matched health participants were enrolled. The mean age in the T1DM group was 10.3 +/- 2.8 years, and the median duration of diabetes was 1 (range 1-3) year. Children with T1DM had thinner average RNFL than control subjects (105 +/- 6 vs. 110 +/- 11 mu m, p=0.008), especially in temporal and nasal parts. There was a significant negative association between HbA1c levels and the RNFL thickness in the T1DM group (B (95 % confidence interval): -4.313 (-7.055 to -1.571); p=0.005). Conclusions: In our study, the decreased thickness of RNFL was negatively associated with elevated HbA1c in children with early stages of T1DM.