Incidence of childhood type 1 diabetes mellitus in Ireland remains high but no longer rising
Amanda McKenna, Myra O’Regan, Kerry J Ryder, Helen Fitzgerald, Hilary Hoey, Edna Roche
Abstract
AIM: The global incidence of type 1 diabetes mellitus (T1DM) varies considerably geographically. Ireland has a high incidence of T1DM. Incidence accelerated between 1997 and 2008, although more recent data (2008-2013) suggested stabilisation in the incidence rate (IR). This study sought to determine IRs for 2014 to 2018. METHODS: Incident cases were prospectively recorded through the established Irish Childhood Diabetes National Register (ICDNR). Cases were verified, and IRs were calculated. Capture-recapture methodology was identical to previous studies. Age and seasonality data were compared. RESULTS: A total of 1429 cases were reported (age range 0.45-14.98 years), with significantly more males (772, 54%) and male-to-female ratio of 1.17 (95% CI 1.05, 1.29). Standardised IRs for T1DM in the period were 28.0; 29.6; 30.9; 27.0; and 27.1/100,000/year, respectively. There was a slight reduction in standardised IR, more marked in females than males (9.9% v 1.6%). The highest IR remains in the 10- to 14-year-old age group (44% of total cases). Seasonality of diagnosis is persistently higher in autumn and winter. CONCLUSION: Ireland remains a high incidence country, despite a minor reduction in incidence rates. Ongoing incidence monitoring through national registers is vital to inform healthcare services, research relating to aetiology and paediatric diabetes management.