Monday March 2 2009
Type 2 diabetes is related to lifestyle factors, including diet and obesity
An expert has said that “fat children should be given gastric bands to tackle diabetes” according to The Daily Telegraph. The newspaper says paediatrician Professor Julian Shield believes that the NHS needs to take more radical measures to prevent serious damage to the health of obese children with ‘weight-related diabetes’.
This and other newspaper stories were based on a study looking at a group of 73 medical cases of adolescent type 2 diabetes. These individuals were followed-up for a year after their diagnosis and were managed in a variety of ways by their doctors. Some were taking medication and others were treated with diet and exercise regimes to manage their weight and diabetes. However, many gained weight rather than losing it, and on balance, this group of cases seemed to be ineffectively treated.
Gastric banding was not the subject of this research, and only one morbidly obese child who had failed medical treatment was awaiting weight-loss surgery. The lead researcher has been quoted as saying that it should be considered in the more serious cases. This study was not set up to compare one treatment with another.
Where did the story come from?
Dr J Shield and colleagues from the Royal College of Paediatrics and Child Health in London, the University of Birmingham, the University of Bristol and the Bristol Royal Hospital for Children carried out this study. The research was funded by a grant from Diabetes UK, and was published in the peer-reviewed medical journal Archives of Diseases in Childhood.
What kind of scientific study was this?
This study was a follow-up report of a case series of adolescents with type 2 diabetes: these adolescent patients were initially enrolled through monthly surveillance of consultant paediatricians in the UK and the Republic of Ireland. The monthly surveillance was carried out by the British Paediatric Surveillance Unit to identify cases of diabetes (not the autoimmune condition of type 1) in 0-16 year olds.
Paediatricians who reported a case of diabetes other than type 1 were sent a questionnaire seeking to collect information about the case, including details of diagnosis, family history, body mass index (BMI), etc. The paediatrician was then sent another questionnaire a year later, asking about insulin, blood glucose, height, weight and comorbidity.
In this research, the researchers only included individuals whose initial diagnosis was for type 2 diabetes. A total of 76 children were selected. The researchers report on how the patients' weight, height and blood pressure changed over the course of the year between the initial and follow-up questionnaires. The researchers also used the information on the number of type 2 diabetes cases to estimate the national incidence (number of new cases over time) for the UK.
What were the results of the study?
At the beginning of the study, the diabetes cases had an average age of 13.6 years. The average BMI was 32.5. After 12 months, follow-up information was available for 96% of the original 76 patients.
On average, the patients’ weight increased by 3.1kg over the year. Overall, 67% of cases had achieved a reduction in their BMI after 12 months. But of these, only 11 children (15%) managed a reasonable reduction (at least half a standard deviation from the mean weight).
The researchers also found that at the beginning of the study, most children (47%) were being treated with Metformin (a drug that decreases glucose production in the body), while 17% made diet and lifestyle changes alone. By the end of the first year, only six children (8%) remained on diet alone/no treatment, while the number receiving Metformin had increased to 44 (61%).
The researchers report that there was no significant improvement in the BMI scores of those children who were initially treated with diet and education but started taking Metformin over the course of the year (10 from an initial 12). Only 58% of the children had blood glucose levels that reached the desired treatment goals.
What interpretations did the researchers draw from these results?
The researchers say that their study has confirmed that the incidence of childhood type 2 diabetes in the UK is 0.6/100,000 per year. They also say that they “have shown that BMI does not improve as much as would be desired with current therapy”, and that the overall change in BMI in the group was “disappointing”, given that lifestyle modification is central to the management of type 2 diabetes.
What does the NHS Knowledge Service make of this study?
This case series study has followed-up children diagnosed with type 2 diabetes in the UK, and reports on the characteristics of the patients one year after diagnosis. According to the researchers, the study highlights shortcomings in the way that paediatric diabetes clinics in the UK managed the participating children’s diabetes.
The researchers have commented on the findings of their study, saying that “given the increasing prevalence of type 2 diabetes in paediatric practice, these poor weight-management figures and evidence of poor metabolic control indicate an urgent need to develop specific strategies to deal with this relatively new patient group”. The researchers say these strategies should feature “culturally sensitive lifestyle and behaviour changes as the cornerstone of therapy”.
This is an important study in that it demonstrates current practice in the way children with type 2 diabetes are managed by this group of paediatric consultants. There are two separate but related issues raised by this study. Firstly, whether children are receiving appropriate clinical treatments in accordance with national treatment guidelines. Secondly, whether treatment with these recommended patient management approaches are effective in this population.
This second question can only be addressed by comparative studies, and one recent systematic review of appropriate literature suggests that a combined behavioural and lifestyle intervention can lead to significant weight reduction in children and adolescents with type 2 diabetes. However, in this widely reported research, there was insufficient information collected at the beginning of this study to determine whether the children were receiving a comprehensive lifestyle intervention.
Overall, this study was not set up to compare one treatment approach with another. It certainly did not compare children managed with gastric bands to those who were not, as might be understood from some of the news headlines. The researchers say that their study indicates that most patients require medication-based therapies from diagnosis, presumably implying that they are not receiving them.
Most of the newspapers focus on gastric banding, quoting the lead researcher as saying that gastric banding “should be considered for the most severe cases”. However, weight-loss surgery in a child or adolescent would only be considered, with great caution, as a last resort when all other therapeutic options have failed. Current NICE guidance for the management of obesity in children advises that surgical intervention is not generally recommended for children or young people, and would only be considered under exceptional circumstances when they have reached, or almost reached, physiological maturity.