To Örebro University

CONTEXT: Neurodevelopmental disorders are more prevalent in childhood-onset type 1 diabetes than in the general population, and the symptoms may limit the individual's ability of diabetes management. It remains unknown whether comorbid neurodevelopmental disorders are associated with long-term glycaemic control and risk of diabetic complications.

METHODS: This population-based cohort study used longitudinally collected data from Swedish registers. We identified 11,326 individuals born 1973-2013, diagnosed with type 1 diabetes 1990-2013 (median onset age: 9.6 years). Out of them, 764 had a comorbid neurodevelopmental disorder, including attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, and intellectual disability. We used multinomial logistic regression to calculate odds ratios (ORs) of having poor glycaemic control (assessed by mean of glycated haemoglobin [HbA1c]) and Cox regression to estimate hazard ratios (HRs) of nephropathy and retinopathy.

RESULTS: The median of follow-up was 7.5 (IQR 3.9, 11.2) years. Having any neurodevelopmental disorder (ORadjusted 1.51 [95%CI 1.13, 2.03]), or ADHD (ORadjusted 2.31 [95%CI 1.54, 3.45]) was associated with poor glycaemic control (mean HbA1c >8.5%). Increased risk of diabetic complications was observed in patients with comorbid neurodevelopmental disorders (HRadjusted 1.72 [95%CI 1.21, 2.44] for nephropathy, HRadjusted 1.18 [95%CI 1.00, 1.40] for retinopathy) and patients with ADHD (HRadjusted 1.90 [95%CI 1.20, 3.00] for nephropathy, HRadjusted 1.33 [95%CI 1.07, 1.66] for retinopathy). Patients with intellectual disability have a particularly higher risk of nephropathy (HRadjusted 2.64 [95%CI 1.30, 5.37]).

CONCLUSIONS: Comorbid neurodevelopmental disorders, primarily ADHD and intellectual disability, were associated with poor glycaemic control and a higher risk of diabetic complications in childhood-onset type 1 diabetes.