DARWIN EU® - Feasibility of studies on early (pre-symptomatic) stages of type 1 diabetes mellitus in the DARWIN EU® network

Study type

• Study topic:
  Disease /health condition
• Study topic, other:
  Type 1 Diabetes mellitus
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Population studied

• Short description of the study population:
  Objectives 1 and 2 (newly diagnosed type 1 diabetes mellitus cohort): ; Inclusion criteria; First-ever recorded diagnosis of type 1 diabetes mellitus during the study period. ; Objective 3: ; Inclusion criteria; • All individuals present in the period from 01/01/2015 to 31/12/2024 (or the first and latest available date); • Minimum 365 days of available history before the index date (applied to non-hospital-based data sources and individuals aged 1 year or older). ;
• Age groups:
  • In utero
  • Paediatric Population (< 18 years)

    • Neonate

      • Preterm newborn infants (0 – 27 days)
      • Term newborn infants (0 – 27 days)
    • Infants and toddlers (28 days – 23 months)
    • Children (2 to < 12 years)
    • Adolescents (12 to < 18 years)
  • Adult and elderly population (≥18 years)

    • Adults (18 to < 65 years)

      • Adults (18 to < 46 years)
      • Adults (46 to < 65 years)
    • Elderly (≥ 65 years)

      • Adults (65 to < 75 years)
      • Adults (75 to < 85 years)
      • Adults (85 years and over)

Study design details

• Study design:
  This study will be conducted using routinely collected data from 6 data sources, including primary care (n=1), hospital care (n=4), and registry-based data settings (n=1) within the DARWIN EU® network of data partners, and from 6 EU member states. All data were a priori mapped to the OMOP CDM.
• Main study objective:
  The aim of this study is to investigate the feasibility of conducting research on the early (pre-symptomatic) stages of type 1 diabetes mellitus within the DARWIN EU® network. It will focus on the frequency and timing of autoantibody and glucose testing before the disease becomes clinically apparent.; The specific objectives for this study are:; 1. To describe the characteristics of individuals newly diagnosed with type 1 diabetes mellitus in terms of demographics, prespecified comorbidities and medications, and diagnostic tests of interest (HbA1C, C-peptide, glucose, and each autoantibody assay), prior to and at the time of type 1 diabetes mellitus diagnosis, and to assess selected characteristics at one-year post-diagnosis. ; 2. To estimate, for each diagnostic test of interest (HbA1C, C-peptide, glucose, and each autoantibody assay), the median (IQR) time in days from 1) the earliest recorded test and 2) the earliest recorded abnormal result (where ascertainable) to the date of first-ever type 1 diabetes mellitus diagnosis. ; 3. To estimate the annual point prevalence of type 1 diabetes mellitus during 2015–2024, using population-based data sources. ;