Type I diabetes in paediatric age in Apulia (Italy): Incidence and associations with outdoor air pollutants

• 13-years incidence stable or decreased, according to age at disease onset.
• A positive correlation was found between T1D incidence and PM10 air levels.
• Higher T1D incidence with PM10 levels in the highest—than in reference tertile.
• Mean age at T1D onset was linked with yearly PM10 air levels.

AimThis study aimed to explore Type 1 diabetes (T1D) incidence and possible relations with specific air pollutants in a large population of children, during a wide time period.MethodsT1D rates and trends were examined (2001–2013, GAM and Joinpoint Regression analysis) by data on the first hospitalization in all children (0–14 years) living in Apulia (Southern Italy, average yearly population aged 0–14 years in the examined period: 631,275 subjects), and linked with levels of PM10, NOx, CO and ozone.ResultsA total of 1501 children were first discharged in the selected area with a diagnosis of T1D. Incidence decreased from 48.5 (95% CI 43.3; 54.0, 2001) to 16.9 per 100,000 (95% CI 13.7; 20.6, 2013), with differences according to age at onset (constant at 0–4 years, continuously decreasing at 5–9 years, decreasing until 2003 at 10–14 years), and with a positive relation with PM10—but not ozone, NOx and CO average air levels. The OR was 1.037 (1.002; 1.074) in the high tertile of PM10 concentrations, and mean incidence was higher with PM10 levels in the highest, than in the medium/reference tertile. Mean age at T1D onset was linked with yearly PM10 and ozone air levels.ConclusionsOn a wide period, a stable or decreased incidence of T1D was evident in children with early- or later onset of disease, respectively. PM10 exposure significantly affects the incidence of T1D, which might be considered, at least in part, a preventable condition.