Twenty years ago, type 2 diabetes was almost unheard of in China. Twenty years later, we are at the forefront of the world – the country with the highest prevalence of type 2 diabetes in the world. According to the statistics available, the number of patients with type 2 diabetes has reached 114 million in China, and the incidence rate of younger patients is becoming more and more obvious. Since 2008, the incidence of type 2 diabetes has increased from 3.2% to 5.9% since the age of 40, and the number of young diabetic patients has increased by 1 times in the past more than 10 years.
For patients with diabetes, testing blood sugar, like eating, is an essential daily activity. At present, the most conventional method is fingertip blood sampling method to detect blood glucose, that is, by puncturing the fingers of patients at different time points to measure blood glucose levels. Because many sugar friends can’t stand the pain of frequent needling, so many people can’t do blood glucose measurement seven times a day. In addition, the instantaneous blood glucose measured by this method is easily affected by many factors, such as exercise, diet, drugs, emotional fluctuations and so on, so there is a certain one sidedness in the measurement results. In addition to the shortcomings of monitoring methods, the feelings of patients (such as pain, inconvenience, etc.) are also one of the main reasons affecting blood glucose monitoring. Therefore, continuous glucose monitor (CGM) and other monitoring equipment came into being, and was quickly welcomed by the majority of diabetic patients. China is the country with the largest number of diabetic patients in the world. In order to cope with this growing market, ADI and China’s leading CGM equipment providers bring benefits to diabetic patients, including cooperating with Meiqi to develop the next generation of integrated ambulatory blood glucose monitoring wearable device.
Say goodbye to fingertip blood collection, CGM provides more accurate monitoring data for patients
CGM is a kind of device which can monitor the glucose concentration of subcutaneous interstitial fluid through glucose sensor, indirectly reflect the blood glucose level, and help patients fully understand the 24-hour dynamic blood glucose fluctuation. It allows users to observe the effects of diet, exercise and insulin dosage on glucose level in real time, and reduce the frequency and severity of hypoglycemia attacks. It also finds hidden hyperglycemia and hypoglycemia that are not easy to be detected by traditional monitoring methods.
In addition, the cost advantage of CGM is also very obvious, which can not only save a lot of needle and test paper use costs, but also help patients successfully monitor symptoms through continuous data obtained by dynamic blood glucose meter in their lifetime, avoiding the high cost of serious medical procedures or hospital visits. Patients with CGM can manage their own health, change their eating habits, take medicine on time, and improve their overall quality of life.
The size, weight and power consumption (SWAP) of CGM are the challenges for the whole industry. After all, CGM is a portable vital sign monitoring (VSM) device worn on diabetic patients, usually connected to the arm or abdomen. But because it requires constant power to collect data, it’s hard to make them big enough to work without affecting the wearer. As a leader in digital healthcare solutions, especially in wearable technology and chronic disease management, this swap challenge is the strength of ADI’s professional solutions. According to the public information, the ADI sensor and the next generation mobile impedance testing technology are used in the dynamic blood glucose monitoring equipment of Meiqi.
ADI can meet the impedance measurement solution in medical field
In the official information, Meiqi chose ADI’s small size, low voltage ad5950 for the next generation of mobile impedance testing technology. The device model is not in the information of ADI official website, but we might as well have a glimpse of the technical characteristics and technical trend of its impedance measurement solution from ADI’s related solutions.
Meiqi dynamic blood glucose monitoring patch integrated with transmitter and replaceable sensor
For all applications, the basic principle of impedance measurement is the same, but the function of single measurement is still very different. For example, for electrochemical impedance analysis, the impedance of an electrochemical cell or sensor is measured at all different frequencies. Through the change of impedance at different frequencies, the sensor wear is measured, and the signal chain is automatically adjusted. When using this kind of measurement, the sensor accuracy will decline with time (days to weeks), which may seriously affect the overall accuracy of various measured values. That’s the problem with CGM. ADI’s impedance measurement solution aducm355 can implement all measurements uniformly. This highly integrated chip includes an energy-saving analog front end (AFE) and a microcontroller, which undertakes management and security functions, such as cyclic redundancy check (CRC). The following figure shows the key components of aducm355.
Block diagram of precision analog microcontroller aducm355 with chemical sensor interface
In the field of medical technology, people are looking for small, energy-saving and low-cost solutions to implant them into wearable and usable devices. ADI’s aducm355 is an on-chip system, which can control electrochemical and biosensors with extremely low power consumption. The device is an ultra-low power mixed signal microcontroller based on armcortex-m3 processor, which can measure current, voltage and impedance.
Most of the sensors used for measurement can be operated directly through aducm355 input. For example, it is used for potentiostat measurement, such as blood glucose measurement. In contrast, to achieve more accurate measurement (such as conductivity and pH value) needs to use extended signal chain, so it also needs to use external chips, such as ltc6078. It increases the input impedance to adapt to the high output impedance of the sensor, so as to obtain accurate readings. With the help of large signal chain, aducm355 can read voltage and current values. In the circuit shown, the impedance range of less than 100 Ω to 10m Ω can be detected, and a larger measurement range can cover the whole impedance spectrum required by the medical field.
Advanced function block diagram of ad594x
Ad594x is a high-precision, low-power analog front-end solution for continuous blood glucose monitoring in ADI official website. This series of chips are specially tailored for medical and industrial applications. The analog front end is fully configurable and can be modified to support a variety of applications, including electrical skin activity (EDA) or electrical skin response (GSR), body impedance analysis, moisture measurement and biochemical measurement. With the development of wearable devices and battery powered systems, the main challenge is to meet the required performance level in the smallest possible size and low power consumption. The ad594x is designed to support today’s wearable market and meet all key requirements, including high precision, small size and low power consumption.
With the change of medicine from passive treatment to active prevention, this medical trend relies on high-quality and continuous access to patient data equipment, such as whether blood glucose is too low due to exercise or too high due to bad eating habits, and can make more accurate, effective and comprehensive judgment based on these test data. With the accurate clinical blood glucose level data provided by CGM, patients can get appropriate insulin treatment, which helps to avoid further diabetic complications, such as vascular injury, heart disease, stroke, kidney disease, diabetic coma and so on.