Tag Archives: glucose levels

Artificial pancreas in 2018?

According to Dr. Roman Hovorka and Dr. Hood Thabit of the University of Cambridge, UK, there will be an artificial pancreas assuming issues such as cybersecurity are resolved. From a June 30, 2016 Diabetologia press release on EurekAlert,

The artificial pancreas — a device which monitors blood glucose in patients with type 1 diabetes and then automatically adjusts levels of insulin entering the body — is likely to be available by 2018, conclude authors of a paper in Diabetologia (the journal of the European Association for the Study of Diabetes). Issues such as speed of action of the forms of insulin used, reliability, convenience and accuracy of glucose monitors plus cybersecurity to protect devices from hacking, are among the issues that are being addressed.

The press release describes the current technology available for diabetes type 1 patients and alternatives other than an artificial pancreas,

Currently available technology allows insulin pumps to deliver insulin to people with diabetes after taking a reading or readings from glucose meters, but these two components are separate. It is the joining together of both parts into a ‘closed loop’ that makes an artificial pancreas, explain authors Dr Roman Hovorka and Dr Hood Thabit of the University of Cambridge, UK. “In trials to date, users have been positive about how use of an artificial pancreas gives them ‘time off’ or a ‘holiday’ from their diabetes management, since the system is managing their blood sugar effectively without the need for constant monitoring by the user,” they say.

One part of the clinical need for the artificial pancreas is the variability of insulin requirements between and within individuals — on one day a person could use one third of their normal requirements, and on another 3 times what they normally would. This is dependent on the individual, their diet, their physical activity and other factors. The combination of all these factors together places a burden on people with type 1 diabetes to constantly monitor their glucose levels, to ensure they don’t end up with too much blood sugar (hyperglycaemic) or more commonly, too little (hypoglycaemic). Both of these complications can cause significant damage to blood vessels and nerve endings, making complications such as cardiovascular problems more likely.

There are alternatives to the artificial pancreas, with improvements in technology in both whole pancreas transplantation and also transplants of just the beta cells from the pancreas which produce insulin. However, recipients of these transplants require drugs to supress their immune systems just as in other organ transplants. In the case of whole pancreas transplantation, major surgery is required; and in beta cell islet transplantation, the body’s immune system can still attack the transplanted cells and kill off a large proportion of them (80% in some cases). The artificial pancreas of course avoids the need for major surgery and immunosuppressant drugs.

Researchers are working to solve one of the major problems with an artificial pancreas according to the press release,

Researchers globally continue to work on a number of challenges faced by artificial pancreas technology. One such challenge is that even fast-acting insulin analogues do not reach their peak levels in the bloodstream until 0.5 to 2 hours after injection, with their effects lasting 3 to 5 hours. So this may not be fast enough for effective control in, for example, conditions of vigorous exercise. Use of the even faster acting ‘insulin aspart’ analogue may remove part of this problem, as could use of other forms of insulin such as inhaled insulin. Work also continues to improve the software in closed loop systems to make it as accurate as possible in blood sugar management.

The press release also provides a brief outline of some of the studies being run on one artificial pancreas or another, offers an abbreviated timeline for when the medical device may be found on the market, and notes specific cybersecurity issues,

A number of clinical studies have been completed using the artificial pancreas in its various forms, in various settings such as diabetes camps for children, and real life home testing. Many of these trials have shown as good or better glucose control than existing technologies (with success defined by time spent in a target range of ideal blood glucose concentrations and reduced risk of hypoglycaemia). A number of other studies are ongoing. The authors say: “Prolonged 6- to 24-month multinational closed-loop clinical trials and pivotal studies are underway or in preparation including adults and children. As closed loop devices may be vulnerable to cybersecurity threats such as interference with wireless protocols and unauthorised data retrieval, implementation of secure communications protocols is a must.”

The actual timeline to availability of the artificial pancreas, as with other medical devices, encompasses regulatory approvals with reassuring attitudes of regulatory agencies such as the US Food and Drug Administration (FDA), which is currently reviewing one proposed artificial pancreas with approval possibly as soon as 2017. And a recent review by the UK National Institute of Health Research (NIHR) reported that automated closed-loop systems may be expected to appear in the (European) market by the end of 2018. The authors say: “This timeline will largely be dependent upon regulatory approvals and ensuring that infrastructures and support are in place for healthcare professionals providing clinical care. Structured education will need to continue to augment efficacy and safety.”

The authors say: “Cost-effectiveness of closed-loop is to be determined to support access and reimbursement. In addition to conventional endpoints such as blood sugar control, quality of life is to be included to assess burden of disease management and hypoglycaemia. Future research may include finding out which sub-populations may benefit most from using an artificial pancreas. Research is underway to evaluate these closed-loop systems in the very young, in pregnant women with type 1 diabetes, and in hospital in-patients who are suffering episodes of hyperglycaemia.”

They conclude: “Significant milestones moving the artificial pancreas from laboratory to free-living unsupervised home settings have been achieved in the past decade. Through inter-disciplinary collaboration, teams worldwide have accelerated progress and real-world closed-loop applications have been demonstrated. Given the challenges of beta-cell transplantation, closed-loop technologies are, with continuing innovation potential, destined to provide a viable alternative for existing insulin pump therapy and multiple daily insulin injections.”

Here’s a link to and a citation for the paper,

Coming of age: the artificial pancreas for type 1 diabetes by Hood Thabit, Roman Hovorka. Diabetologia (2016). doi:10.1007/s00125-016-4022-4 First Online: 30 June 2016

This is an open access paper.

Wearable device to monitor and control diabetes is based on graphene

The research comes from Korea’s Institute of Basic Science and was announced in a March 22, 2016 news article by Lee Chi-dong for Yonhap News Agency,

A team of South Korean scientists announced Tuesday [March 22, 2016] that they have developed a wearable device, based on nanotechnology, for more convenient diabetes monitoring and therapy.

The graphene-using “smart patch” has improved the accuracy of blood sugar level measurements as it checks not only glucose in sweat but also temperature and acidity, according to the Institute for Basic Science (IBS) located in Daejeon, some 160 kilometers south of Seoul.

Existing smart patches gauge blood sugar merely in sweat.

Google is working on “smart contact lens” with an ultra-tiny super sensitive glucose sensor for tear fluid. Its accuracy remains a question amid concerns about adverse effects on eye health.

A March 21, 2016 IBS press release on EurekAlert provides more details about the work,

A scientific team from the Center for Nanoparticle Research at IBS has created a wearable GP [graphene]-based patch that allows accurate diabetes monitoring and feedback therapy by using human sweat. The researchers improved the device’s detecting capabilities by integrating electrochemically active and soft functional materials on the hybrid of gold-doped graphene and a serpentine-shape gold mesh. The device’s pH and temperature monitoring functions enable systematic corrections of sweat glucose measurements as the enzyme-based glucose sensor is affected by pH (blood acidity levels) and temperature.

Diabetes and regulating glucose levels

Insulin is produced in the pancreas and regulates the use of glucose, maintaining a balance in blood sugar levels. Diabetes causes an imbalance: insufficient amounts of insulin results in high blood glucose levels, known as hyperglycemia. Type 2 diabetes is the most common form of diabetes with no known cure. It affects some 3 million Koreans with the figure increasing due to dietary patterns and an aging society. The current treatments available to diabetics are painful, inconvenient and costly; regular visits to a doctor and home testing kits are needed to record glucose levels. Patients also have to inject uncomfortable insulin shots to regulate glucose levels. There is a significant need for non-invasive, painless, and stress-free monitoring of important markers of diabetes using multifunctional wearable devices. The IBS device facilitates this and thereby reduces the lengthy and expensive cycles of visiting doctors and pharmacies.

Components of the graphene-based wearable device

KIM Dae-Hyeong, a scientist from the Center for Nanoparticle Research, describes the vast array of components: “Our wearable GP-based device is capable of not only sweat-based glucose and pH monitoring but also controlled transcutaneous drug delivery through temperature-responsive microneedles. Precise measurement of sweat glucose concentrations are used to estimate the levels of glucose in the blood of a patient. The device retains its original sensitivity after multiple uses, thereby allowing for multiple treatments. The connection of the device to a portable/ wireless power supply and data transmission unit enables the point-of-care treatment of diabetes.” The professor went on to describe how the device works, “The patch is applied to the skin where sweat-based glucose monitoring begins on sweat generation. The humidity sensor monitors the increase in relative humidity (RH). It takes an average of 15 minutes for the sweat-uptake layer of the patch to collect sweat and reach a RH over 80% at which time glucose and pH measurements are initiated.”

Merits of the device and drug administration

The device shows dramatic advances over current treatment methods by allowing non-invasive treatments. During the team’s research, two healthy males participated in tests to demonstrate the sweat-based glucose sensing of the device. Glucose and pH levels of both subjects were recorded; a statistical analysis confirmed the reliable correlation between sweat glucose data from the diabetes patch and those from commercial glucose tests. If abnormally high levels of glucose are detected, a drug is released into a patient’s bloodstream via drug loaded microneedles. The malleable, semi-transparent skin-like appearance of the GP device provides easy and comfortable contact with human skin, allowing the sensors to remain unaffected by any skin deformations. This enables stable sensing and efficient drug delivery.

The scientific team also demonstrated the therapeutic effects by experimenting on diabetic (db/db) mice. Treatment began by applying the device near the abdomen of the db mouse. Microneedles pierced the skin of the mouse and released Metformin, an insulin regulating drug, into the bloodstream. The group treated with microneedles showed a significant suppression of blood glucose concentrations with respect to control groups. “One can easily replace the used microneedles with new ones. Treatment with Metformin through the skin is more efficient than that through the digestive system because the drug is directly introduced into metabolic circulation through the skin,” commented KIM Dae-Hyeong. He went on: “These advances using nanomaterials and devices provide new opportunities for the treatment of chronic diseases like diabetes.”

The researchers have made an image illustrating their work available,

Caption: Optical image of the GP-hybrid electrochemical device array on the human skin Credit: IBS

Caption: Optical image of the GP-hybrid electrochemical device array on the human skin Credit: IBS

Here’s a link to and a citation for the paper,

A graphene-based electrochemical device with thermoresponsive microneedles for diabetes monitoring and therapy by Hyunjae Lee, Tae Kyu Choi, Young Bum Lee, Hye Rim Cho, Roozbeh Ghaffari, Liu Wang, Hyung Jin Choi, Taek Dong Chung, Nanshu Lu, Taeghwan Hyeon, Seung Hong Choi, & Dae-Hyeong Kim. Nature Nanotechnology (2016) doi:10.1038/nnano.2016.38 Published online 21 March 2016

This paper is behind a paywall.