Patient and product benefits

It is a well-known fact that patients with autonomic neuropathy have an increased risk of developing cardiovascular disesase. Hitherto, further risk stratification of the heterogenous patient group has not been possible based on conventional cardiovascular risk factors. Many patients suffer in silence since the disease tends to develop without symptoms. The disease affects the autonomic nervous system, which, among other things, controls the heart rate.

According to international recommendations, autonomic neuropathy tests of patients with type 1 diabetes should be made five years after the time of diagnosis and then once every year, whereas tests of patients with type 2 diabetes should be made at the time of diagnosis and hereafter once every year (1,2). 

Conventional screening is both time consuming (about 1 hour per test) and cost-intensive, as it is performed in a hospital laboratory with specially trained staff and with an apparatus consisting of several devices.

Using Vagus™ the total test will take less than 10 minutes. It can be performed in outpatient clinics or by a general practitioner, and in the near future, even at home by the patient himself/herself. This device, a Danish design, is the only one to scientifically prove it possible to move the complicated autonomic neuropathy tests from the dedicated laboratory milieu with specially trained staff (3-5) to where the patient actually is. Vagus™ is the only device which can be used for internationally recommended large scale screening of diabetic autonomic neuropathy (6,7).   

References

1. Guidelines on diabetes, pre-diabetes, and cardiovascular diseases: executive summary. The Task Force on Diabetes and Cardiovascular Diseases of the European Society of Cardiology (ESC) and of the European Association for the Study of Diabetes (EASD). Eur Heart J 28(1):88-136, 2007
2. Boulton AJ, Vinik AI, Arezzo JC, Bril V, Feldman EL, Freeman R, Malik RA, Maser RE, Sosenko JM, Ziegler D: Diabetic neuropathies: a statement by the American Diabetes Association. Diabetes Care 28(4):956-962, 2005
3. Fleischer J, Nielsen R, Laugesen E, Nygaard H, Poulsen P, Ejskjaer N: White-Coat Effect in Testing for Cardiovascular Autonomic Neuropathy (Abstract). Journal of Diabetes Science and Technology 5(4): 2011
4. Fleischer J, Nielsen R, Laugesen E, Nygaard H, Poulsen PL, Ejskjaer N: Self-monitoring of cardiac autonomic function at home is feasible. J Diabetes Sci Technol 5(1):107-112, 2011
5. Fleischer J, Ballegaard AS, Eskildsen KG, Damgaard H, Nygaard H, Hoffmeyer V, Ejskjaer N: A Technological and Clinical Feasibility Study: Testing for Diabetic Autonomic Neuropathy in General Practice and in a Home Setting (Abstract). Eleventh Diabetes Technology Meeting 2011
6. Charles M, Fleischer J, Witte DR, Ejskjaer N, Borch-Johnsen K, Lauritzen T, Sandbaek A: Impact of early detection and treatment of diabetes on the 6-year prevalence of cardiac autonomic neuropathy in people with screen-detected diabetes: ADDITION-Denmark, a cluster-randomised study. Diabetologia 56(1):101-108, 2013
7. Gulichsen E, Fleischer J, Ejskjaer N, Eldrup E, Tarnow L: Screening for Diabetic Cardiac Autonomic Neuropathy Using a New Handheld Device. Journal of Diabetes Science and Technology 6(4):965-972, 2012

NEUROPATI

Clinical issues in neuropathy

Neuropathy is a common complication in diabetes (though not only in diabetes). The symptoms of neuropathy may be weak and uncharacteristic for years and are therefore easily overlooked. Thus, the disease is often diagnosed very late and unfortunately often when permanent nerve damage is recognised.

Autonomic neuropathy screening is internationally recommended five years after the time of diagnosis of type 1 diabetes and at the time of diagnosis of type 2 diabetes. Hereafter, yearly screenings of both groups are recommended.

Diabetic autonomic neuropathy

The symptoms of autonomic neuropathy typically appear long after the diabetic debut and it may be disabling for the patient. The complications may be hypoglycaemia, unawareness, dizziness, tendency to perspire, recurrent cystitis, urinary retention and impotence. The multi factual symptoms reflect that autonomic neuropathy may affect any organ which is innervated by the autonomic nervous system.

Using Vagus™ autonomic neuropathy can be identified in patients both with and without symptoms. The first symptom of autonomic neuropathy is usually reduced parasympathetic modulation (1).

Stratification level – course

Regardless of other complications, the presence of autonomic neuropathy is a bad prognostic symptom and should change the stratification level for the patient and lead to decisions on diagnosis, treatment and future control.

Written by:

External independent experts

Christian Stevns Hansen, Physician, PhD-student, Steno Diabetes Center

Marit Eika Jørgensen, Professor, Chief Physician, PhD, Steno Diabetes Center

Lise Tarnow, Head of Research, Professor, DMSc, Hillerød Hospital

In collaboration with Jesper Fleischer, Associate Professor, PhD, the Medical Research Laboratory, Aarhus University and Aarhus University Hospital and Medicus Engineering

RESEARCH

Research in autonomic dysfunction

Vagus™ is based on many years of biomedical research. Via the palm of the patient’s hands, the device measures the electrical signals generated by every heart beat (ECG-signal). The extremely accurate measures can be used to deduce information about heart rate variability (HRV).

Over the years, the screening method has generated much attention as a commonly known research instrument for measuring balance/imbalance in the autonomic nervous system. Both in humans and animals, a correlation between HRV and the degree of autonomic modulation has been found.

HRV is a result of both internal and external changes in respiration, blood pressure, hormone status, mental condition, physical condition and a series of pathophysiological conditions, which may reduce or increase the stimulation of the heart sinus node. An imbalance/dysfunction in the autonomic nervous system is usually without symptoms, but may be recorded as changes in HRV-measurements.

Detailed analysis

HRV is defined as the variation from heart beat to heart beat (R-R-interval) and HRV measurements obtained by the use of Vagus™ follow international recommendations.

Only one device is necessary. Vagus™ both contains electronics for heart rate recording and sensors for measuring pressure. The device stores all data, including raw data (R-R-intervals), and this can be transferred for analysis to a computer with software for that purpose. The combination of measurements of various physiological signals and concurrent detailed data analysis is exactly what enables such complicated autonomic dysfunction screening to be made in a cost effective way.

No time for preparation and minimal training

A great advantage of Vagus™ is that the device is simply hand-held. A user-friendly display guides the patient through four standard exercises while measurements are recorded automatically. The integrated exercise guidance ensures a minimal need for staff training in the use of the device.

TECHNOLOGY

Technical specifications