Assessing Interpersonal Variability in Postprandial Glucose Responses to Food in People With Type 1 Diabetes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 150
- 试验地点
- 1
- 主要终点
- Glucose AUC
研究概览
简要总结
Type 1 diabetes (T1D) is a lifelong disease which stops the body from producing insulin - an important hormone that controls blood sugar (glucose) levels. People with T1D use insulin replacement therapy, usually in the form of injections, to help control blood glucose levels, however keeping glucose levels within normal ranges is usually a challenge. Mealtime glucose control is fundamental to good diabetes management and are an important contributor to long-term diabetes complications. However, many individuals experience variability in glucose levels around mealtimes. The objective of this study is to establish whether and which parameters are important predictors of mealtime glucose levels in people with T1D.
The investigators will monitor glucose levels using the latest glucose monitoring technology and collect blood samples to:
- Characterise changes in glucose levels in individuals with T1D in response to different meals
- Determine whether and what food characteristics and personal factors are linked to individual glucose responses to different meals.
The investigators will recruit 150 individuals with type 1 diabetes. Firstly participants will attend a preliminary visit, where a blood sample will be donated to study laboratory blood markers of vascular and metabolic health accompanied by a full medical examination in which body composition will be established. During this visit participants will also complete questionnaires about their lifestyle, and be fitted with two wearable devices to monitor glucose levels and physical activity levels under free-living conditions.
After 4-weeks of wearing the devices, participants will attend two experimental laboratory visits where breakfast and lunch will be served and blood samples taken. This will enable us to observe glucose and metabolic responses to feeding under controlled conditions.
详细描述
Recruitment: Participants will be recruited using advertisements through university channels. The investigators will also approach local and national diabetes charities (Diabetes UK, JDRF) who the investigators work with closely to advertise through written publications (patient magazines), websites, social media, and patient support groups. In addition, the investigators will contact patients who have previously participated in our research who have consented to being contacted about future research. Contact information for the research team will be provided in advertisements; an initial telephone call will be available to interested participants to discuss the study, answer any questions, and obtain contact information to send a study information pack including a participant information sheet. Participants will be given 6-weeks to decide whether to participate in the study.
Preliminary visit: Patients will attend a preliminary visit to our dedicated laboratories at the University of Sunderland to assess eligibility and obtain written informed consent by a GCP trained member of the research team. At this visit, consented participants will be fitted with a blinded real-time CGM and an accelerometer and provided with a food diary. During this visit, patients will complete a questionnaire to assess their medical history and physical activity. Both CGM and accelerometer devices will be worn by participants for the duration of their study involvement; both devices complete with data capture will be returned by participants to the research team either in person or via post (using a prepaid envelope).
CGM measurement: A small CGM device (CGM; Freestyle Libre Pro; Abbott Diabetes Care) will be inserted during the preliminary visit to the laboratory. It is a small discreet, water-resistant sensor, with a thin filament (<0.4m thick) that is inserted (painlessly) 5mm beneath the skin surface on the upper arm. The sensor will be inserted into the subcutaneous tissue on the anterior of the upper arm. The insertion site will be taken as equidistant between the most medial portion of the upper arm and marked with indelible ink so that initial placement can be replicated on subsequent insertions in the unlikely event that a sensor should fail. The sensor is factory calibrated making it far more convenient and removing the risk for sensor inaccuracies from calibration user error (capillary meter inaccuracy, not washing hands etc) seen with other CGM devices. Glucose data generated by the CGM is masked (i.e., participants cannot see their glucose data and thus cannot change their treatment regimen based on this information). A single reader device is used to activate and retrieve the data. The accuracy and safety of this device has been established in T1D across the full range of glucose levels likely to be observed in this study, including those in the normal range; the latest generation of the CGM sensor has a MARD of <9% as of 2018. Moreover, as an un-blinded version of this device is now made available to people with T1D with treatment indications through the NHS, the use of this technology is deemed acceptable to people with T1D. Study participants who are using Freestyle Libre to monitor their glucose patterns can continue to use the device as usual but will be asked to wear an additional blinded sensor. In total, patients will be requested to wear the CGM device for 6 continuous weeks, consisting of 4-weeks observation followed by 2-weeks observation during which laboratory experimental testing will occur.
Accelerometer: Participants will be issued and fitted with an accelerometer (GeneActiv, worn on the arm) which will provide a comprehensive assessment of sitting/standing patterns (i.e. posture allocated) and physical activity levels. The data collected from this device will be used to estimate daily energy expenditure (using a priori cut points) and calculate physical activity levels including time spent in different postures and activities during discrete parts of the day both before and after each laboratory visit. This will allow for quantification, standardisation and replication of physical activity patterns during free-living episodes. In total, patients will be requested to wear the accelerometer device for 2 continuous weeks.
Medical history: To include: age, gender, duration of diabetes, insulin therapy (average total daily dose and basal insulin dose), associated medical conditions, family history of T2D and cardiovascular disease, hypoglycaemia unawareness (assessed through a combination of the Clarke and Gold methods).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Double (Participant, Investigator)
盲法说明
Double blind
入排标准
- 年龄范围
- 18 Years 至 70 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Gender/sex, race/ethnicity, sexual orientation, and religion are not
排除标准
- •for this study
- •Inclusion Criteria:
- •A diagnosis of T1D for a minimum of 5 years;
- •Currently treated on a stable insulin regimen for a minimum of 6 months consisting of continuous subcutaneous insulin infusion (CSII) therapy or multiple daily injections (MDI) of a combination of rapid-acting and long-acting insulin;
- •Familiar and currently using the carbohydrate-counting method for determining mealtime insulin dose;
- •Not currently pregnant;
- •No overt diabetes complications including end stage renal failure requiring dialysis;
- •Free from hypoglycaemia unawareness assessed through a combination of the Clarke64 and Gold65 methods66;
- •No recent (<6-months) history of diabetic ketoacidosis (DKA);
- •Free from medical conditions relating to a haematological disorder, gut mobility or digestion; No history of anorexia, bulimia, or any other disordered eating;
- •No history of deep vein thrombosis;
- •No history of heart attack or stroke within 6 months prior to recruitment;
- •No history of malignancy; No existing medical or psychiatric conditions likely to interfere with the study;
- •No dietary allergies or intolerances likely to interfere with the study;
- •Able to understand written English and provide written informed consent.
- •Exclusion Criteria:
- •A diagnosis of T1D for less than 5 years;
- •Not currently treated on a stable insulin regimen for more than 6 months consisting of continuous subcutaneous insulin infusion (CSII) therapy or multiple daily injections (MDI) of a combination of rapid-acting and long-acting insulin;
- •Unfamiliar and not currently using the carbohydrate-counting method for determining mealtime insulin dose;
- •Currently pregnant or planning on becoming pregnant during study involvement;
- •Presence of overt diabetes complications including end stage renal failure requiring dialysis;
- •Presenting with hypoglycaemia unawareness assessed through a combination of the Clarke and Gold methods; Recent (<6-months) history of diabetic ketoacidosis (DKA);
- •Presenting with medical conditions relating to a haematological disorder, gut mobility or digestion;
- •Presenting with a history of anorexia, bulimia, or any other disordered eating;
- •Presenting with a history of deep vein thrombosis;
- •Presenting with a history of heart attack or stroke within 6 months prior to recruitment;
- •History of malignancy;
- •Presence of existing medical or psychiatric conditions likely to interfere with the study;
- •Presenting with dietary allergies or intolerances likely to interfere with the study;
- •Unable to understand written English and provide written informed consent.
研究组 & 干预措施
Low GI
Consumption of standardised low-GI mixed-macronutrient breakfast-based meal followed by a standardised low-GI mixed-macronutrient lunch meal 4 hours later.
干预措施: Nutritional Interventional (Other)
High GI
Consumption of a standardised high-GI mixed-macronutrient breakfast-based meal followed by a standardised high-GI mixed-macronutrient lunch meal 4 hours later.
干预措施: Nutritional Interventional (Other)
结局指标
主要结局
Glucose AUC
时间窗: 4 hours
Glucose Area Under the Curve calculated using the trapezoid method (mmol.L.hr)
次要结局
- Hyperglycaemia(4 hours)
- Glycaemic variability(4 hours)
- Mean glucose(4 hours)
- Hypoglycaemia(4 hours)
- TNF-a(4 hours)
- Fibrinogen(4 hours)
- PAI-1(4 hours)
- TF(4 hours)