India is among the countries with highest estimated T1D prevalence.
“Given that prevalence of people with T1D is projected to increase in all countries to up to 17.5 million cases in 2040, our results provide a warning for substantial negative implications for societies and healthcare systems,” said Graham Ogle from Sydney Medical School, University of Sydney, who is, one of the authors of the study.
“There is an opportunity to save millions of lives in the coming decades by raising the standard of care for T1D (including ensuring universal access to insulin and other essential supplies) and increasing awareness of the signs and symptoms of T1D to enable a 100% rate of diagnosis in all countries,” he said.
Historically, T1D is seen as a disease with onset in childhood, but in 2021 it was estimated that there were numerically more adults (316,000) diagnosed with T1D than children and adolescents (194,000), with a mean diagnosis age of 32 years.
In 2021, the model estimated that 8.4 million individuals worldwide were living with T1D. Of these, 18% were under 20 years old, 64% were between 20-59 years, and 19% were over 60 years. Ten countries with the highest estimated T1D prevalence are the USA, India, Brazil, China, Germany, the UK, Russia, Canada, Saudi Arabia, and Spain. They account for 5.08 million (60%) of global cases of T1D. Model estimates also suggest that 21% of individuals with T1D live in low-income countries (LICs) and lower middle income countries (LMICs).
World Bank currently classifies India as an LMIC.
Model estimates place global deaths due to T1D at 175,000 in 2021. Of these, 35,000 or 20% were attributed to non-diagnosis, of which 14,500 were in sub-Saharan Africa and 8,700 were in South Asia.
Researchers estimate that an extra 3.1 million people would have been alive in 2021 if they hadn’t died prematurely due to suboptimal care of T1D, and a further 700,000 people would still be alive if they hadn’t died prematurely due to non-diagnosis.
Researchers hope that by making country-specific prevalence and mortality metrics publicly available as part of an open-source database for T1D Index Project, health outcomes can be improved with universal health coverage and better surveillance.
Researchers modelled data on childhood, adolescent and adult T1D prevalence in 97 countries, along with incidence over time data from 65 countries and mortality data from 37 countries to predict T1D incidence, prevalence, and mortality in 2021 for 201 countries, with projections of future prevalence through 2040.
(With inputs from health)