Growth Trajectory in Children with Type 1 Diabetes Mellitus: The Impact of Insulin Treatment and Metabolic Control

Background: Linear growth was reported to be negatively affected by type 1 diabetes mellitus (T1DM), in relation to disease duration and poor metabolic control. It is unclear whether a subtle growth failure still persists despite the optimization of therapy. Our aim was to analyse pubertal growth, adult height, and metabolic profile in a cohort of children with T1DM undergoing intensive insulin treatment by multiple daily injections or continuous subcutaneous insulin infusion (CSII). Methods: One-hundred and four children (51 males) with prepubertal onset of T1DM were prospectively followed up to final height attainment. Results: Age at puberty onset was 11.7 ± 1.1 years in males and 10.9 ± 1.3 in females. Age at adult height attainment was 16.4 ± 1.6 years in males and 14.1 ± 1.8 years in females. Pubertal height gain was 24.4 ± 4.9 cm in males and 19.0 ± 3.8 cm in females. HbA1c, HDL cholesterol, and triglyceride levels increased during puberty. HDL cholesterol levels were higher in patients treated with CSII. Height standard deviation score (SDS) at diagnosis (0.52 ± 1.04) was higher than target height SDS (0.01 ± 1.07), but declined afterwards, and both height SDS at puberty onset (0.22 ± 1.1) and adult height SDS (-0.1 ± 1.02) were not significantly different from target height SDS. BMI SDS showed a positive trend from diagnosis to puberty onset and stabilized later (-0.04 ± 1.4 at T1DM onset, 0.55 ± 2.1 at puberty onset, and 0.53 ± 2.1 at adult height attainment). Conclusions: Although subtle abnormalities of growth still persist, the modern advancements of insulin therapy are able to normalize puberty and final height of children with T1DM.