A plan to improve global type 1 diabetes epidemiology data.

The discovery and subsequent introduction of insulin therapy in 1922 led to fundamental changes in the treatment and epidemiology of type 1 diabetes. In Boston, MA, USA, the life expectancy of people with type 1 diabetes diagnosed at age 10 years increased from 2·6 years during 1914–1922 to 45 years during 1939–1945.1Gale EA Is there really an epidemic of type 2 diabetes?.Lancet. 2003; 362: 503-504Summary Full Text Full Text PDF PubMed Scopus (29) Google Scholar Therefore, type 1 diabetes is not only a condition of young people.3Green A Hede SM Patterson CC et al.Type 1 diabetes in 2017: global estimates of incident and prevalent cases in children and adults.Diabetologia. 2021; 64: 2741-2750Crossref PubMed Scopus (45) Google Scholar, 4Gregory GA Robinson TIG Linklater SE et al.Global incidence, prevalence, and mortality of type 1 diabetes in 2021 with projection to 2040: a modelling study.Lancet Diabetes Endocrinol. 2022; 10: 741-760Summary Full Text Full Text PDF PubMed Scopus (60) Google Scholar Reduced life expectancy of people with type 1 diabetes compared with the general population still persists at a global level,2Livingstone SJ Levin D Looker HC et al.Estimated life expectancy in a Scottish cohort with type 1 diabetes, 2008–2010.JAMA. 2015; 313: 37-44Crossref PubMed Scopus (389) Google Scholar but survival rates continue to improve, especially in high-income countries. In many settings, diabetes registries have contributed to an improved understanding of diabetes epidemiology and has led to improvements in care.5Khunti K Mathieu C Torbeyns B Del Prato S Heine R Diabetes registries and high-quality diabetes care.Lancet Diabetes Endocrinol. 2023; 11: 70-72Summary Full Text Full Text PDF PubMed Scopus (1) Google Scholar Ward and colleagues6Ward ZJ Yeh JM Reddy CL et al.Estimating the total incidence of type 1 diabetes in children and adolescents aged 0–19 years from 1990 to 2050: a global simulation-based analysis.Lancet Diabetes Endocrinol. 2022; 10: 848-858Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar provided novel estimates of incidence of type 1 diabetes in people aged 0–19 years that account for health-system performance. They suggest 355 900 incident cases of type 1 diabetes globally in people aged 0–19 years,6Ward ZJ Yeh JM Reddy CL et al.Estimating the total incidence of type 1 diabetes in children and adolescents aged 0–19 years from 1990 to 2050: a global simulation-based analysis.Lancet Diabetes Endocrinol. 2022; 10: 848-858Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar which is 1·8 times higher than the estimates from Gregory and colleagues4Gregory GA Robinson TIG Linklater SE et al.Global incidence, prevalence, and mortality of type 1 diabetes in 2021 with projection to 2040: a modelling study.Lancet Diabetes Endocrinol. 2022; 10: 741-760Summary Full Text Full Text PDF PubMed Scopus (60) Google Scholar and 2·4 times higher than the estimates of the International Diabetes Federation (appendix).7International Diabetes FederationIDF Diabetes Atlas.10th edition. International Diabetes Federation, Brussels2021Google Scholar Validation of these estimates is difficult as fatal hyperglycaemia might be missed with current autopsy practices.8Blackstock S Witham MD Wade AN et al.Ability of verbal autopsy data to detect deaths due to uncontrolled hyperglycaemia: testing existing methods and development and validation of a novel weighted score.BMJ Open. 2019; 9e026331Crossref PubMed Scopus (2) Google Scholar Both papers also include estimates of missing and undiagnosed cases, as well as future predictions of numbers of incident cases of type 1 diabetes, on the basis of existing incomplete data. This required substantial assumptions that are acknowledged as limitations by the authors of both papers.4Gregory GA Robinson TIG Linklater SE et al.Global incidence, prevalence, and mortality of type 1 diabetes in 2021 with projection to 2040: a modelling study.Lancet Diabetes Endocrinol. 2022; 10: 741-760Summary Full Text Full Text PDF PubMed Scopus (60) Google Scholar, 6Ward ZJ Yeh JM Reddy CL et al.Estimating the total incidence of type 1 diabetes in children and adolescents aged 0–19 years from 1990 to 2050: a global simulation-based analysis.Lancet Diabetes Endocrinol. 2022; 10: 848-858Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar Although the methods and resulting data differ between the studies by Gregory and colleagues4Gregory GA Robinson TIG Linklater SE et al.Global incidence, prevalence, and mortality of type 1 diabetes in 2021 with projection to 2040: a modelling study.Lancet Diabetes Endocrinol. 2022; 10: 741-760Summary Full Text Full Text PDF PubMed Scopus (60) Google Scholar and Ward and colleagues6Ward ZJ Yeh JM Reddy CL et al.Estimating the total incidence of type 1 diabetes in children and adolescents aged 0–19 years from 1990 to 2050: a global simulation-based analysis.Lancet Diabetes Endocrinol. 2022; 10: 848-858Summary Full Text Full Text PDF PubMed Scopus (6) Google Scholar and other global estimates (appendix),3Green A Hede SM Patterson CC et al.Type 1 diabetes in 2017: global estimates of incident and prevalent cases in children and adults.Diabetologia. 2021; 64: 2741-2750Crossref PubMed Scopus (45) Google Scholar, 7International Diabetes FederationIDF Diabetes Atlas.10th edition. International Diabetes Federation, Brussels2021Google Scholar, 9Institute for Health Metrics and EvaluationGBD Results.https://vizhub.healthdata.org/gbd-resultsDate: 2019Date accessed: November 17, 2022Google Scholar they all highlight the scarcity of data on incidence and mortality for type 1 diabetes, especially in people older than 19 years. We therefore propose a plan to increase knowledge of type 1 diabetes epidemiology to improve services and outcomes. This plan includes actions at global and national levels. At a global level, mapping data gaps in existing estimates as well as targeted studies to address these gaps are needed. Re-launching global studies, such as the WHO Diabetes Mondiale study and the EURODIAB register, broadening their scope beyond incidence studies in childhood and adolescence, and developing guidelines and tools to assist countries in data collection should be done. At a national level, developing targeted studies of incidence, prevalence, mortality (including causes), and proportion of undiagnosed cases in specific countries to address existing gaps in knowledge is needed. Existing published and unpublished information on type 1 diabetes needs to be documented by local stakeholders. It is also important to collect information on complications and deaths, if available and accessible in patient file reviews, routine registrations, and monitoring of quality of care or research projects. The development of sustainable ongoing data collection and registers and links with existing global initiatives, such as SWEET, with expansion to all ages should be encouraged. Khunti and colleagues5Khunti K Mathieu C Torbeyns B Del Prato S Heine R Diabetes registries and high-quality diabetes care.Lancet Diabetes Endocrinol. 2023; 11: 70-72Summary Full Text Full Text PDF PubMed Scopus (1) Google Scholar suggest guidance on the development of registries in Europe for type 2 diabetes. Many of these recommendations are relevant also for type 1 diabetes and are in line with our proposed plan. Improved data collection will be essential to monitor WHO's first global coverage targets for diabetes10WHOFirst-ever global coverage targets for diabetes adopted at the 75th World Health Assembly.https://www.who.int/news-room/feature-stories/detail/first-ever-global-coverage-targets-for-diabetes-adopted-at-the-75-th-world-health-assemblyDate: 2022Date accessed: August 30, 2022Google Scholar introduced at the 75th World Health Assembly. These targets include “100% of people with type 1 diabetes having access to affordable insulin and blood glucose self-monitoring”. An improved understanding of type 1 diabetes epidemiology is essential in achieving this goal. DB received a visiting professorship grant for this work from the Danish Diabetes Academy (VP003-21). All other authors declare no competing interests. Download .pdf (.21 MB) Help with pdf files Supplementary appendix