title: Increasing incidence of type 1 diabetes between 1986 and 2015 in Bauru, Brazil.
abstract: OBJECTIVE
  To assess temporal trends in the incidence of type 1 diabetes in Bauru, São Paulo State, Brazil from 1986 to 2015.
  
  
  METHODS
  The yearly incidence of type 1 diabetes (per 100,000/yr) from 1986 to 2015 was determined in children ≤14yr of age, using individual case notification and the capture and recapture method.
  
  
  RESULTS
  During thirty years (1986-2015), 302 cases were diagnosed in our population. The overall incidence was of 12.8/100,000 (95% CI: 11.2-14.4), ranging from 2.8/100,000 in 1987 to 25.6/100,000 in 2013 with a 9.1-fold variation. It was non-significantly higher in girls [13.7 (95% CI: 11.4-16.1)] than in boys [12.0 (95% CI: 9.8-14.2)] (p=0.48) and significantly higher in the 5-9yr [14.6 (95% CI: 11.8-17.4)] and 10-14yr [15.8 (95% CI: 12.7-18.8)] age ranges compared to the 0-4yr [8.1 (95% CI: 6.0-10.2)] age range (p<0.001). The majority of diagnoses were made in colder months. The patterns of incidence were very high and high in 80.0% of the study-years.
  
  
  CONCLUSIONS
  The incidence of type1 diabetes in children ≤14yr has increased in Bauru, Brazil, in the last thirty years, in approximately 3.1% annually, with an absolute crude increase of 2.5-fold. These findings pose Brazil as a country with high incidence of type 1 diabetes. All Brazilian regions should be enrolled in future studies to determine the factors that contribute to the predisposition to type 1 diabetes in our population and to the steep rise in its incidence.
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil. Electronic address: carlosnegrato@uol.com.br.
authors.forename: Carlos Antonio
authors.initials: CA
authors.lastname: Negrato
authors.affiliation: Department of Pediatric Dentistry, Orthodontics and Community Health, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil.
authors.forename: José Roberto Pereira
authors.initials: JRP
authors.lastname: Lauris
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Ieso Braz
authors.initials: IB
authors.lastname: Saggioro
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Maria Cristina Morato
authors.initials: MCM
authors.lastname: Corradini
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Pricila Rubia
authors.initials: PR
authors.lastname: Borges
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Crês
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Aluysio Leal
authors.initials: AL
authors.lastname: Junior
authors.affiliation: Bauru's Diabetics Association, Department of Internal Medicine, Bauru, São Paulo, Brazil.
authors.forename: Maria Fatima Soares
authors.initials: MFS
authors.lastname: Guedes
authors.affiliation: Department of Internal Medicine, Diabetes Unit, State University Hospital of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Marilia Brito
authors.initials: MB
authors.lastname: Gomes
mesh_terms: D000293:Adolescent; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology*; D005260:Female; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D015994:Incidence; D008297:Male
keywords: Brazil; Childhood; Incidence; Type 1 diabetes