Type 2 diabetics don’t always receive advanced warning that they are about to lose consciousness from a drop in blood glucose levels. Common symptoms of passing out include sweating, tingling or numbness in the face, a feeling of intense hunger and heart palpitations. But in patients who have lived with diabetes for a long period of time, the symptoms aren’t always present before an episode. Performing a finger prick test is still the most reliable way to determine if blood sugar levels are dropping too low.
However, that may change within a few years. Research has shown that a diabetic’s sweat pattern undergoes changes when blood glucose levels drop too low. Now a sweat meter developed jointly at the University of Olso in Norway and the National Hospital may be able to monitor sweat patterns to determine irregularities in blood glucose levels and send an alert via text message before the patient suffers an attack.
Better yet, the sweat meter could supercede finger pricking as the primary mechanism for quickly testing blood glucose levels in diabetics. “The advantage of the sweat meter is that the patient doesn’t have to prick themselves,” said Professor Ørjan G. Martinsen with the Department of Physics at the University of Oslo. “All you need to do is paste an electrode on your skin.”
“We envisage that the device will be able to measure sweat activity continuously, providing an indication of whether the patient is about to experience low blood sugar,” said Christian Tronstad, a medical technology researcher at the Oslo University Hospital. “It can communicate directly or via a smartphone. The warning system will then not be very bothersome for the patient.”
The project is being supported by the Norwegian Diabetes Association. Researchers are now conducting studies to determine if changes in sweat patterns can be viable indicators of dangerous blood glucose levels. “In the study we will compare the continuous measurements of sweat activity and blood sugar in patients to see if we can get a good enough warning of a low sugar level in the blood,” said Tronstad.
Kåre Birkeland, head of the medical council of the Norwegian Diabetes Association, believes that the sweat meter holds exciting possibilities in streamlining blood glucose testing and providing advance warning of attacks from low blood sugar for diabetics. “It can be developed into a practical, usable device that can help those who have a hypo when their blood sugar gets too low. The patient can then take the necessary precautions,” said Birkeland.
The sweat meter was actually developed to diagnose hyperhidrosis, or a condition that causes excessive sweating. It sends a small electrical current through the outermost layers of skin, which moves into the sweat glands and then returns to the surface of the skin. When the skin has sweat on it, the electrical current reacts to its salt content and notifies the meter that sweat is present on the skin.
Professor Martinsen leads a team that is at the forefront of research dealing with the electrical properties of the skin. Martinsen has worked for over 20 years with Sverre Grimnes, professor emeritus of medical technology at the University of Oslo, on researching and studying bioimpedance, or the electrical resistance properties of biological tissues. The research team calls itself the Bioimpedance Group; they have started a scientific journal to present their findings.