Cataract in children and adolescents with type 1 diabetes. Insights from the German/Austrian DPV registry.

OBJECTIVE: To study diabetic cataract in type 1 diabetes in a large pediatric cohort. METHODS: The 92,633 patients aged 0.5-21 years from German/Austrian multicenter diabetes registry (DPV) were analyzed. The 235 patients (0.25%) with diabetic cataract were found, 200 could be categorized: 67 with early cataract (3 months before diabetes onset - 12 months afterwards), 133 with late cataract (>12 months after diabetes onset). Regression models adjusted for age and gender were used to compare clinical parameters at diabetes onset. Regression models for patients with late cataract were implemented for the total documentation period and additionally adjusted for diabetes duration. RESULTS: Rate of cataract development shows a peak at diabetes onset and declines with longer diabetes duration. Patients with cataract showed strong female preponderance. Patients developing early cataract were older at diabetes onset (12.8 years [11.8/13.9] vs. 8.9 [8.9/9.0]; p < 0.001) and showed higher HbA1c than patients without cataract (9.0% [8.55/9.38] vs. 7.6% [7.60/7.61]; p < 0.001). They had lower height-SDS, (-0.22 [-0.48/0.04] vs. 0.25 [0.24/0.26]; p < 0.001), lower weight-SDS (-0.31 [-0.55/-0.08] vs. 0.21 [0.20/0.21]; p < 0.001) and lower BMI-SDS (-0.25 [-0.49/-0.02] vs. 0.12 [0.12/0.13); p = 0.002). Patients with late cataract showed higher HbA1c at diabetes onset (8.35% [8.08/8.62] vs. 8.04% [8.03/8.05]; p = 0.023) and higher mean HbA1c during total documentation period (8.00% [7.62/8.34] vs. 7.62% [7.61/7.63]; p = 0.048). CONCLUSIONS: Our data confirm known demographic and clinical characteristics of patients developing early cataract. Hyperglycemia-induced osmotic damage to lens fibers at diabetes onset might be the main pathomechanism. Long term glycemic control is associated with cataract development.