This is a plain English summary of an original research article
The number of children being diagnosed with both type 1 and type 2 diabetes is rising, but new cases of type 2 diabetes, the form associated with being overweight, has risen five-fold in about five years. New analysis in this NIHR-supported study suggest that type 2 diabetes now accounts for up to a third of diabetes diagnoses in children.
Amongst 100,000 school age children about six new cases of type 2 diabetes a year could be expected in the 1990s. This increased to about 33 new cases per year by the end of the next decade (2009 to 2013). Data was taken from the UK Clinical Practice Research Datalink, a primary care database of electronic health records.
Children who are obese have about a four times greater risk of developing type 2 diabetes compared with those of a normal weight. Having type 2 diabetes brings an increased risk of other complications and healthcare problems for individuals and is associated with extra resource use and costs for society.
NICE has produced guidance about preventing type 2 diabetes, but it appears that more needs to be done to promote healthier lifestyles to children and their families.
Why was this study needed?
The number of children and young people in England and Wales with both diabetes type 1 and 2 has been rising for several years. Obesity is a well-known risk factor for type 2 diabetes in adults. But there has been little large-scale research about the link between childhood obesity and diabetes.
Over a third of children and young adults were overweight or obese in the UK in 2015, with one in five children obese by the time they leave primary school.
This study aimed to examine trends in the incidence of both types of diabetes, as well as any association between high BMI and diagnosis of diabetes.
What did this study do?
This retrospective cohort study analysed electronic health records from 375 general practices in England that contribute to the UK Clinical Practice Research Datalink. They looked for a diagnosis of type 1 or 2 diabetes from data of 369,362 children aged two to 15 who had body mass index (BMI) measurements recorded between 1994 and 2013.
The authors also conducted a case-control study, matching each child with diabetes with up to four randomly selected control children of the same sex, age and general practice. They used this data to estimate the risks of developing diabetes for different BMI ranges.
This study can only show associations between BMI and diagnoses of diabetes, not causation. Other factors which could influence development of diabetes, such as physical activity, do not appear to have been taken into account. The authors note that information on weight and height were not available for all children in the database, so there may be some measurement bias in the group of children studied.
What did it find?
- About a third of cases of diabetes in the cohort were type 2 diabetes: 654 cases of type 2, compared to 1,318 cases of type 1 diabetes.
- The incidence of both type 1 and type 2 diabetes in children under 15 increased between 1994 and 2013.
- For type 1 diabetes, the incidence rose from 38.2 per 100,000 persons per year in the 1994-98 period (95% confidence interval [CI] 30.4 to 47.2) to 52.1 (95% CI 47.6 to 56.9) in 2009-13.
- For type 2 diabetes, there was an increase from 6.4 per 100,000 persons per year in 1994-98 (95% CI 3.5 to 10.7) to 33.2 (95% CI 29.7 to 37.1) in 2009-13.
- Obese children were about four times more likely to have type 2 diabetes than those with a normal BMI: odds ratio 3.7 (95% CI 3.1 to 4.6).
- The incidence of type 1 diabetes showed no association with BMI categories.
What does current guidance say on this issue?
In 2015, NICE updated its guidance on the diagnosis and management of diabetes in children and young people to include recommendations relating to type 2 diabetes for the first time. The guidance includes specific recommendations about dietary management for children and young people with type 2 diabetes who are overweight or obese. NICE also has public health guidance on preventing type 2 diabetes, which makes recommendations about promoting healthier lifestyles and addressing misconceptions about what constitutes a healthy weight.
What are the implications?
Children developing type 2 diabetes used to be rare, but figures from this study suggest that as many as a third of cases of diabetes in children under the age of 15 could now be type 2.
The study also confirms the strong link between obesity and type 2 diabetes in children. This highlights the need to find ways of promoting healthy lifestyles and habits in childhood alongside education initiatives for families, to minimise the risk of developing type 2 diabetes.
Type 1 diabetes is still more common than type 2 in children, and this isn’t associated with being overweight. The findings of this study illustrate the differences, and why it is important not to just refer to “diabetes”, but to distinguish between types 1 and 2.
Citation and Funding
Abbasi A, Juszczyk D, van Jaarsveld C, et al. Body Mass Index and Incident Type 1 and Type 2 Diabetes in Children and Young Adults: A Retrospective Cohort Study. J Endocr Soc. 2017;(5):524-37.
One of the authors is supported by the NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London.
NHS Choices. Reduce your diabetes risk. London: Department of Health; 2016.
NICE. Diabetes (type 1 and type 2) in children and young people: diagnosis and management. NG18. London: National Institute for Heath and Care Excellence; 2015.
NICE. Type 2 diabetes prevention: population and community-level interventions. London: National Institute for Health and Care Excellence; 2011.
NIHR. Evidence for action on type 2 diabetes. London: National Institute for Health Research; 2016.
The Conversation. How can we prevent type 2 diabetes in children. London; 2016.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre