Incidence of type 1 diabetes in Navarra, 2009-2020. Evidence of a stabilization

The evolution of the incidence of type 1 diabetes (T1D) in all groups is controversial. Our objective is to study the incidence from 2009 to 2020, based on the Type 1 Diabetes Registry of Navarra, and to analyze the clinical presentation as diabetic ketoacidosis (DKA), and HbA1c at onset.

Descriptive study of all cases diagnosed as T1D and included in the Population Registry of T1D of Navarra in the period 1/1/2009 to 12/31/2020. Data are obtained from primary and secondary sources with an ascertainment rate of 96%. Incidence rates are expressed per 100,000 person-years of risk, by age group and sex. Likewise, a descriptive analysis of the HbA1c and DKA at diagnosis of each patient is performed.

627 new cases are registered, which represents an incidence of 8.1 (10 in men, 6.3 in women), without differences throughout the analyzed period. The group with the highest incidence is the 10-14 years old children (27.8), followed by that of 5-9 years old (20.6). The incidence in people older than 15 years is 5.8. Twenty six percent of patients present DKA at onset. The global mean of HbA1c is 11.6%, without changes throughout the studied period.

The population registry of T1D of Navarra shows a stabilization in the incidence of T1D at all ages in the 2009-2020 period. The percentage of presentation as severe forms is high, even in adulthood.