Clinical trial NCT01279161: The Role of FTO Gene Polymorphism and Insulin Preparation in Obesity in Children With Type 1 Diabetes Mellitus
Official title: The Role of FTO Gene Polymorphism and Insulin Preparation in Overweight/Obesity in Children With Type 1 Diabetes Mellitus
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Type 1 Diabetes Mellitus
Keywords: overweight, obesity, children, insulin, pump therapy, FTO
Lead sponsor: University of Bialystok
Sponsor class: OTHER_GOV
First posted: 2011-01-19
Enrollment: 2000
Sex: ALL
Minimum age (years): 6
Maximum age (years): 18
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The study will include 1500 children with type 1 diabetes, aged 6-18 years. These will be patients from Diabetes Outpatient Clinics and patients hospitalized in Departments of Paediatrics, Endocrinology and Diabetology in University and Municipal Hospitals from all over Poland (Białystok, Warszawa, Gdańsk, Katowice, Wrocław). Reference group will be made of 1500 children from the above mentioned Clinics and Departments in whom type 1 diabetes was excluded. In these children diagnostics procedures will be conducted for reasons other than body weigh related diseases (excluding simple obesity). The children will not receive any treatment that might influence their body weight.

Brief summary: The project aims at assessment of the effect of the FTO gene polymorphism and the type of treatment on the development of overweight/obesity and features of metabolic syndrome in children with type 1 diabetes.

Gene polymorphism including some genetic variants may predispose to the development of cardiovascular diseases and their complications. The A allele of the FTO gene predisposing to obesity occurs in approximately 40% of the European population and each copy of this allele can increase BMI by 0.1 Z-score i.e. by 0.4 kg/m2. Insulin therapy in diabetic patients may result in excess body weight gain. Therefore we need studies involving large groups of children and assessing cardiovascular risk factors in type 1 diabetes along with their genetic associations.

Patients: The study will include 1500 children with type 1 diabetes, aged 6-18 years. Reference group will be made of 1500 children in whom type 1 diabetes was excluded. The following variables will be assessed in the treatment group: 1) Anthropometric data and questionnaire data: age, sex, body height and weight, body mass index (BMI), waist and hip circumferences, arm and thigh circumferences, family history of overweight/obesity, type 1 or 2 diabetes or cardiovascular disease, 2) Primary disease characteristics: age of the disease onset, treatment regimen, mean daily insulin consumption per kg body weight, brands of insulin products, glycated haemoglobin, BMI from the first 3-6 months following diabetes onset, diet, conversion of these data into actual and ideal calorie intake 3) Laboratory data - lipid profile and blood pressure (average of three measurements). Methodology: Gene polymorphism analysis in the extracted DNA will be made with the real-time PCR method using TaqMan 7900 HT by Applied Biosystems. Correlations between the FTO gene polymorphism and clinical variables such as BMI (including BMI increase since the disease onset), body weight and height, waist and hip circumferences, arm and thigh circumferences, and blood pressure will be assessed by a professional statistician with a specially dedicated software. Moreover parameters such as diet and metabolic control will be assessed. As regards insulin therapy the following variables will be analysed: insulin injection device, therapy regimen (intensive versus functional; brands and types of insulin products: human insulin versus insulin analogue), consumption of insulin. All of the above listed variables will be correlated with the genotypes found in the gene polymorphism analysis. The study has been approved by Bioethics Committee of the Medical University in Białystok.

Results: The authors of the project expect that the effect of the FTO gene polymorphism on overweight/obesity and features of metabolic syndrome in children with type 1 diabetes will be shown. Moreover the project will enable assessment of the effect of the therapeutic regimen, including the type of insulin product, on body weight increase in the course of type 1 diabetes treatment in the context of the FTO gene polymorphism. Confirmation of the above associations and identification of a group at risk of excess body weight increase in the course of insulin therapy may help physicians, parents and patients to avoid this complication. Therefore clinical benefit of this project will include identification - based on the genetic assays results - of a group of type 1 diabetic children particularly likely to develop overweight, obesity and other cardiovascular risk factors.

Detailed description: Aim:

The project aims at assessment of the effect of the FTO gene polymorphism and the type of treatment on the development of overweight/obesity and features of metabolic syndrome in children with type 1 diabetes. Particular objective of the project is providing an answer to the question: Are type 1 diabetic children who are carriers of the AA genotype of the FTO gene polymorphism (rs9939609) at risk of more weight gain in the course of insulin therapy when compared to carriers of the TA and TT genotypes of this polymorphism ? Background: Gene polymorphism including some genetic variants may predispose to the development of cardiovascular diseases and their complications. A great advance in studies on genetic susceptibility to obesity was the discovery of the gene called FTO - fat mass and obesity associated gene. The A allele of the FTO gene predisposing to obesity occurs in approximately 40% of the European population and each copy of this allele can increase BMI by 0.1 Z-score i.e. by 0.4 kg/m2. However, there are very few data on the impact of human genome on body weight change following particular intervention.

An important problem to be dealt with by physicians and type 1 diabetic patients is overweight and obesity. This problem is inevitably associated with insulin therapy and excess energy intake. Insulin therapy in diabetic patients may result in excess body weight gain. The exact mechanisms underlying this phenomenon are not known. Obesity in patients diagnosed with diabetes can be an additional risk factor of cardiovascular disease. Central obesity, insulin resistance, dyslipidaemia and arterial hypertension are all the elements of metabolic syndrome - a disease that predisposes to the development of cardiovascular disorders. Cardiovascular complications are the main cause of morbidity and mortality in adult patients with diabetes. However recently repeated attempts have been made to assess these factors also in children and adolescents. Overweight and obesity in type 1 diabetes depend among others on patients' sex, age and type of treatment. Although the role of gene polymorphism in the development of obesity in adults and children is the subject of extensive investigations, currently there are no reports that would assess genetic aspects of obesity in treatment of type 1 diabetes. Therefore we need studies involving large groups of children and assessing cardiovascular risk factors in type 1 diabetes along with their genetic associations.

Patients: The study will include 1500 children with type 1 diabetes, aged 6-18 years. Reference group will be made of 1500 children in whom type 1 diabetes was excluded.

The following variables will be assessed in the treatment group: 1) Anthropometric data and questionnaire data: age, sex, body height and weight, body mass index (BMI) (including SDS-BMI), waist and hip circumferences, arm and thigh circumferences, family history of overweight/obesity, type 1 or 2 diabetes or cardiovascular disease, 2) Primary disease characteristics: age of the disease onset, treatment regimen (intensive insulin therapy versus functional insulin therapy with a personal insulin pump), mean daily insulin consumption per kg body weight, brands of insulin products, glycated haemoglobin (the last available measurement and the mean value from the last year), BMI from the first 3-6 months following diabetes onset, diet - consumption of carbohydrate and protein-fat exchanges (only in patients using a personal insulin pump), conversion of these data into actual and ideal calorie intake 3) Laboratory data: lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) and blood pressure (average of three measurements). In the control group anthropometric variables and questionnaire data will be assessed along with additional questions.

Methodology: Gene polymorphism analysis in the extracted DNA will be made with the real-time PCR method using TaqMan 7900 HT by Applied Biosystems. Correlations between the FTO gene polymorphism and clinical variables such as BMI (including BMI increase since the disease onset), body weight and height, waist and hip circumferences, arm and thigh circumferences, and blood pressure will be assessed by a professional statistician with a specially dedicated software (R-project). Moreover parameters such as diet and metabolic control will be assessed. As regards insulin therapy the following variables will be analysed: insulin injection device, therapy regimen (intensive versus functional; brands and types of insulin products: human insulin versus insulin analogue), consumption of insulin. Out of laboratory data, lipid metabolism parameters will be assessed. All of the above listed variables will be correlated with the genotypes found in the gene polymorphism analysis. The study has been approved by Bioethics Committee of the Medical University in Białystok.

Results: The authors of the project expect that the effect of the FTO gene polymorphism on overweight/obesity and features of metabolic syndrome in children with type 1 diabetes will be shown. Moreover the project will enable assessment of the effect of the therapeutic regimen, including the type of insulin product, on body weight increase in the course of type 1 diabetes treatment in the context of the FTO gene polymorphism. Confirmation of the above associations and identification of a group at risk of excess body weight increase in the course of insulin therapy may help physicians, parents and patients to avoid this complication. Therefore clinical benefit of this project will include identification - based on the genetic assays results - of a group of type 1 diabetic children particularly likely to develop overweight, obesity and other cardiovascular risk factors.

Eligibility criteria: Inclusion Criteria:

* children of Polish origin
* diagnosed with type 1 diabetes (defined according to the ADA 2010)
* treated with insulin therapy for at least 1 year
* aged ≥ 6 \< 18 years
* receiving the same treatment regimen for at least one year
* insulin requirement of \> 0.5 U/kg/daily

Exclusion Criteria:

* no consent given by parents/guardians
* chromosome disorders
* autoimmune diseases
* coeliac disease (biopsy-proven)
* thyroid hormone disorders (but not the presence of antithyroid antibodies)
* treatment that might influence body weight
* newly diagnosed diabetes (either type 1, 2, 3 or other types of diabetes)

Primary outcomes:
measure: Identification of the effect of the FTO gene polymorphism on the development of overweight/obesity in insulin treated children
timeFrame: one year
Secondary outcomes:
measure: • Identification of the effect of the following factors: sex, age, duration of disease, therapy regimen, type of insulin product and degree of metabolic control on the development of overweight/ obesity in insulin treated children
timeFrame: one year
measure: • Identification of the effect of genetic polymorphism of the FTO gene on the incidence of metabolic syndrome features in insulin treated children.
timeFrame: one year
measure: • Identification of the effect of genetic polymorphism of the FTO gene on the incidence of overweight, obesity and metabolic syndrome features in children without diabetes.
timeFrame: one year
measure: • Comparison of frequency distribution of FTO gene polymorphism involved in the pathogenesis of obesity in children with diabetes versus children without diabetes.
timeFrame: one year
Other outcomes:
Locations:
city: Wrocław
country: Poland
facility: Department of Pediatrics, Endocrinology and Diabetology, Medical University
state: Dolnośląskie
city: Warsaw
country: Poland
facility: Department of Pediatrics, Medical University
state: Mazowieckie
city: Bialystok
country: Poland
facility: Department of Pediatrics, Endocrinology, Diabetology with Cardiology Division, Medical University
state: Podlaskie
city: Gdańsk
country: Poland
facility: Department of Pediatrics, Hematology, Oncology and Endocrinology, Medical University
state: Pomorskie
city: Łódź
country: Poland
facility: Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University
state: Łódzkie
city: Katowice
country: Poland
facility: Department of Pediatrics, Endocrinology and Diabetology, Medical University
state: Śląskie
Study officials:
affiliation: Medical University of Bialystok, Poland
name: Wlodzimierz Luczynski, Ass. Prof.
role: STUDY_CHAIR
affiliation: Medical University of Bialystok, Poland
name: Adam Kretowski, Prof
role: PRINCIPAL_INVESTIGATOR
References:
citation: Timpson NJ, Emmett PM, Frayling TM, Rogers I, Hattersley AT, McCarthy MI, Davey Smith G. The fat mass- and obesity-associated locus and dietary intake in children. Am J Clin Nutr. 2008 Oct;88(4):971-8. doi: 10.1093/ajcn/88.4.971.
citation: Frayling TM, Timpson NJ, Weedon MN, Zeggini E, Freathy RM, Lindgren CM, Perry JR, Elliott KS, Lango H, Rayner NW, Shields B, Harries LW, Barrett JC, Ellard S, Groves CJ, Knight B, Patch AM, Ness AR, Ebrahim S, Lawlor DA, Ring SM, Ben-Shlomo Y, Jarvelin MR, Sovio U, Bennett AJ, Melzer D, Ferrucci L, Loos RJ, Barroso I, Wareham NJ, Karpe F, Owen KR, Cardon LR, Walker M, Hitman GA, Palmer CN, Doney AS, Morris AD, Smith GD, Hattersley AT, McCarthy MI. A common variant in the FTO gene is associated with body mass index and predisposes to childhood and adult obesity. Science. 2007 May 11;316(5826):889-94. doi: 10.1126/science.1141634. Epub 2007 Apr 12.
citation: Reinehr T, Holl RW, Roth CL, Wiesel T, Stachow R, Wabitsch M, Andler W; DPV-Wiss Study Group. Insulin resistance in children and adolescents with type 1 diabetes mellitus: relation to obesity. Pediatr Diabetes. 2005 Mar;6(1):5-12. doi: 10.1111/j.1399-543X.2005.00093.x.
citation: Luczynski W, Szypowska A, Glowinska-Olszewska B, Bossowski A. Overweight, obesity and features of metabolic syndrome in children with diabetes treated with insulin pump therapy. Eur J Pediatr. 2011 Jul;170(7):891-8. doi: 10.1007/s00431-010-1372-7. Epub 2010 Dec 8.
citation: Luczynski W, Fendler W, Ramatowska A, Szypowska A, Szadkowska A, Mlynarski W, Chumiecki M, Jarosz-Chobot P, Chrzanowska J, Noczynska A, Brandt A, Mysliwiec M, Glowinska-Olszewska B, Bernatowicz P, Kowalczuk O, Bossowski A. Polymorphism of the FTO Gene Influences Body Weight in Children with Type 1 Diabetes without Severe Obesity. Int J Endocrinol. 2014;2014:630712. doi: 10.1155/2014/630712. Epub 2014 Aug 19.