Type 1 diabetes and autism association seems to be linked to the incidence of diabetes

• Published in: Diabetes Care
• Main Authors: IAFUSCO D, SONGINI M, CHIARI G, CARDELLA F, FIFI A, LOMBARDO F, MARINARO A, MELIA A, MARSCIANI A, VACCA A, PRISCO F., VANELLI, Maurizio
• Other Authors: Iafusco, D, Vanelli, Maurizio, Songini, M, Chiari, G, Cardella, F, Fifi, A, Lombardo, F, Marinaro, A, Melia, A, Marsciani, A, Vacca, A, Prisco, F.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 2006
• Subjects: Northern Finland
• Online Access: http://hdl.handle.net/11381/1508469; https://doi.org/10.2337/dc06-0842

We read with interest the article of Freeman et al. (1) reporting a higher prevalence of autism spectrum disorder in pediatric patients with type 1 diabetes in Toronto than in the general population (0.9% [95% CI 0.3–1.5 vs. 0.34–0.67]). The finding was, however, not confirmed by Harijutsalo and Tuomilehto (2), who reported a prevalence of autism spectrum disorders in type 1 diabetic patients similar to that in the population aged <18 years in northern Finland (0.135% [95% CI 0.5–2.8] vs. 0.139% [1.2–1.57]). In Italy, we have “our own Finland,” namely Sardinia. Italy has a peculiar epidemiology of type 1 diabetes. Sardinia has one of the highest incidences in the world (42.4/100 [95% CI 40.5–44.4]), while peninsular Italy has an overall incidence that is similar to other Mediterranean areas (8.4/100 [7.9–8.9], 11.2/100 [10.3–12.2] in North Italy, and 6.2/100 [5.8–6.7] in South Italy) (3). Only 2 of 1,373 patients aged <14 years from the Sardinian Registry of type 1 diabetes were diagnosed with autism spectrum disorders (0.1456% [0.13–0.16]), a finding similar to the Finnish data. On the contrary, a pattern similar to that observed by Freeman et al. (1) has been found in patients with type 1 diabetes aged <14 years from six Italian centers of pediatric diabetology equally distributed in the Italian Peninsula and in Sicily (0.72% [0.69–0.75]). The diagnosis of autism spectrum disorder was confirmed in all cases using the DSM-IV (Diagnostic and Statistic Manual of Mental Disorders-IV). Autism spectrum disorder includes autism, Asperger disorder, pervasive developmental disorders (not otherwise specified), Rett’s syndrome, and childhood disintegrative disorder. Its prevalence in the general Italian population is estimated at 0.1%. Our data seem to confirm the observation that the prevalence of autism in patients with type 1 diabetes is inversely associated to the incidence trends of diabetes in the observed areas. According to Daneman (4), if the relationship between autism and diabetes is based on shared ...