Blood glucose monitoring is an important part of managing diabetes. Seeing whether your numbers are up or down tells you whether your treatment is working and if you need to adjust your diet or change your insulin dose.
A decade or so ago, the only way to measure your blood sugar was to prick your finger and collect your blood on a test strip. This manual (and sometimes painful) process can get old very fast, especially if you need to check your blood sugar levels several times a day.
Monitoring blood glucose has come a long way since then. Technologies like continuous glucose monitoring (CGM), closed-loop systems, and noninvasive monitoring have automated the process. In some cases they've eliminated the dreaded fingerstick.
These high-tech glucose monitoring devices are the future of diabetes management.
Continuous Glucose Monitoring (CGM)
All CGM systems work in much the same way. A small sensor placed under your skin -- usually on your arm or belly -- measures the glucose levels in the fluid between the cells every few minutes around the clock. Depending on the system, it then sends the data wirelessly to a handheld receiver similar to a cell phone, an app on your smartphone, or an insulin pump.
You can download your glucose data and share it with your doctor so they can use it to adjust your treatment plan for better control of your blood sugar. Your doctor will let you know when you need to use fingersticks along with your monitor to manage your diabetes.
Most people who use CGM have type 1 diabetes, but it's also being studied for type 2 diabetes.
You'll need to calibrate most of these devices with a fingerstick blood test using a standard glucose meter. Only a few of these devices eliminate the need for physical blood testing.
There's an App for That
There are apps to help us make travel plans and manage our money. Why shouldn't they help us manage diabetes, too?
Apps are being developed to help you monitor your blood sugar levels and share readings with your doctor over your mobile devices. Soon apps may be able to deliver insulin, too.
Tandem's t:connect mobile app pairs with the company's insulin pump. It lets you deliver or cancel an insulin bolus straight from your smartphone.
Your real pancreas releases the hormone insulin after you eat to lower your blood sugar. Then it releases another hormone, glucagon, between meals to raise your blood sugar. An artificial pancreas aims to do the same thing. The technology isn't quite there, but it's getting close.
Most of the artificial pancreas systems available today are called hybrid closed-loop systems. They're mainly for people with type 1 diabetes.
A closed-loop system monitors your blood glucose level throughout the day using CGM. Based on your blood glucose level, it figures out how much insulin you need and delivers it through a pump. You still need to count carbs at each meal and enter the total into the system to figure out your bolus dose.
The current systems also can't deliver glucagon if your blood sugar gets too low. Researchers are working on developing a dual hormone system, and it may be available in the future.
Glucose Monitoring Without the Stick
Most glucose monitors measure blood sugar in your blood or fluid with a sensor. Even if you can avoid the finger prick, you'll still have to stick the sensor under your skin.
sugarBEAT calls itself the world's first noninvasive CGM. It's a patch that runs a very slight electric current through your skin to measure glucose in the fluid under your skin. sugarBEAT already has clearance in Europe, and the company has applied for FDA approval in the United States.
The K'Watch uses an array of tiny microneedles to measure blood glucose in fluid right under the skin. The company that makes it claims the device is "painless." K'Watch is in clinical trials.
Other glucose monitoring methods don't require any contact with your blood or fluids. These noninvasive testing methods measure glucose in your body's fluids through the skin of your finger, belly, wrist, or earlobe. Some use light, while others use radio waves. But they all measure the signal that glucose gives off when it interacts with these forms of energy.
A few of these types of devices are approved in Europe but not in the United States. One of the biggest problems with them has been accuracy. It's hard for these devices to tell the difference between the signal from glucose and the signal given off by water and other substances in the blood.
Other devices in the works are trying to use easier-to-access fluids like sweat, tears, or saliva to measure blood sugar. Time will tell which, if any, of these monitoring systems will be able to give a result accurate enough to be useful for people with diabetes.
Photo Credit: Jon Feingersh Photography Inc / Getty Images
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