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

AIM

This 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.

METHODS

T1D 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.

RESULTS

A 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.

CONCLUSIONS

On 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.