Cardiovascular Effects of Rapidly Declining Plasma Glucose in Patients With Type 1 Diabetes

Steno Diabetes Centers

Status: Completed

Conditions: Type 1 Diabetes

Treatments: Other: Rapidly declining plasma glucose; Other: Slowly declining plasma glucose

Study type: Interventional

Funder types: Other

Identifiers

NCT04800536

H-20033627

Details and patient eligibility

About

Type 1 diabetes (T1D) is an autoimmune metabolic disease characterised by impaired lack of endogenous insulin causing elevated plasma glucose levels and increased risk of microvascular and macrovascular complications. With respect to the cardiovascular system, patients with T1D have an up to 10-fold increased risk of sudden cardiac death compared to healthy individuals. Furthermore, diabetes constitutes a hypercoagulable state, which to some extent may explain why cardiovascular disease still is a major cause of mortality in patients with T1D. Due to treatment with exogenously delivered insulin, glycaemic variability with intra-day and inter-day plasma glucose concentrations fluctuating between high levels (peaks) and low levels (nadirs), are inevitable in patients with T1D. A potentially important factor in development of cardiovascular disease, associated with glycaemic variability, is the rate of increase and/or decline of plasma glucose. The aim of this study is to test the hypothesis that a rapid plasma glucose decline from a hyperglycaemic level to an euglycaemic level can induce changes in QT-interval and blood coagulation in a proarrhythmogenic and prothrombotic way.

Twenty patients with T1D with a 1:1 distribution with chronic hyperglycaemia (HbA1C ≥63 mmol/mol) and with well-controlled diabetes (HbA1C ≤53 mmol/mol) will be recruited for a crossover study including two test days (protocols), P-rapid, a combined hyperglycaemic and euglycaemic clamp with rapidly declining plasma glucose and P-slow, a combined hyperglycaemic and euglycaemic clamp with slowly declining plasma glucose. Patients will be randomised 1:1 to start with P-rapid or P-slow. The cardiovascular effects will be investigated using Holter-ECG, Thrombelastography, Echocardiography and blood sampling.

Given that cardiovascular disease is a major cause of death in patients with T1D and that patients with diabetes may be more susceptible for cardiac arrhythmias and thrombotic events compared to healthy individuals, it is important to identify cardiovascular risk factors related to acute changes in plasma glucose in order to improve prevention strategies and therapy.

Enrollment: 20 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion criteria - chronic hyperglycaemia cohort

• Informed and written consent
• Type 1 diabetes
• Age ≥18 years
• C-peptide negative (<0.2 nmol/l)
• Insulin treatment for ≥1 year
• HbA1C ≥63 mmol/mol

Inclusion criteria - well-controlled cohort

• Informed and written consent
• Type 1 diabetes
• Age ≥18 years
• C-peptide negative (<0.2nmol/l)
• Insulin treatment for ≥1 year
• HbA1C ≤53 mmol/mol

Exclusion criteria - both cohorts

• Arrhythmia diagnosed prior to or at the time of the screening visit
• ECG with left or right bundle branch block diagnosed prior to the screening visit.
• Implantable cardioverter defibrillator or pacemaker at the time of inclusion
• Heart failure diagnosed prior to the screening visit (left ventricular ejection fraction < 45%)
• Structural heart disease (Wolf-Parkinson-White syndrome, congenital heart disease, severe valve disease)
• Thyroid dysfunction (except for well-regulated myxoedema)
• Anaemia (male: haemoglobin <8.0 mmol/l; female: haemoglobin <7.0 mmol/l)
• Treatment with anticoagulant or antiplatelet treatment
• Bleeding disorder diagnosed prior to the screening visit

Withdrawal criteria

• The participants may withdraw at will at any time

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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20 participants in 2 patient groups

Cardiovascular effects of rapidly declining plasma glucose

Experimental group

Description:

A combined hyperglycaemic and euglycaemic clamp with a rapidly declining plasma glucose (\>0.15 mmol/l/min). Plasma glucose will be measured every 5 minute and cardiovascular effects of the plasma glucose decline rate will be assessed using Holter-ECG, echocardiography, thrombelastography and blood sampling.

Treatment:

Other: Rapidly declining plasma glucose

Cardiovascular effects of slowly declining plasma glucose

Experimental group

Description:

A combined hyperglycaemic and euglycaemic clamp with slowly declining plasma glucose (\<0.085 mmol/l/min). A combined hyperglycaemic and euglycaemic clamp with a slowly declining plasma glucose (\>0.15 mmol/l/min). Plasma glucose will be measured every 5 minute and cardiovascular effects of the plasma glucose decline rate will be assessed using Holter-ECG, echocardiography, thrombelastography and blood sampling.

Treatment:

Other: Slowly declining plasma glucose