Artificial pancreas offers hope to diabetes patients

An artificial pancreas developed by Boston researchers shows considerable promise to dramatically change the treatment of type 1 diabetes, potentially enabling 2 million Americans to eat what they want without counting carbohydrates or calculating insulin injections, researchers announced Sunday.

Investigators from Massachusetts General Hospital and Boston University developed the experimental device, which consists of an automated pump that releases the hormones insulin and glucagon and a glucose monitoring system controlled by an iPhone app.

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“We encouraged them to eat whatever they wanted while they wore the bionic pancreas,” said Dr. Steven Russell, an endocrinologist at Massachusetts General Hospital who led the study. “They went on a diabetes vacation, eating ice cream, candy bars, and other things they normally wouldn’t eat — like taking out a new sports car and seeing what it can do.”

In a new study published online in the New England Journal of Medicine, the researchers found that 52 adults and teens who used the mobile system for five days had healthier blood sugar levels compared to when they used standard treatments that required them to check their own blood sugar levels and determine how much insulin to inject via a pump device.

“This is not a cure,” said study coauthor Edward Damiano, an associate professor of biomedical engineering at Boston University who holds a patent on the software that makes the automatic dosing decisions. “It’s taking diabetes management to its ultimate potential and unburdens people with type 1 diabetes from thinking about all the things that go into managing diabetes every day of their lives.”

Damiano, whose 15-year-old son developed type 1 diabetes during his first year of life, said he wakes up two to three times a night to check his son’s blood sugar to prevent it from falling to a dangerously low level, called hypoglycemia, which can cause seizures, a coma, and sometimes even death. Having an automated device, which is expected to become available by 2017 after more testing and upgrades, would save Damiano and other parents from having to wake up in the middle of the night to avoid medical emergencies, he said.

Children with type 1 diabetes are eight times more likely to die from severe hypoglycemia at night — called dead in bed syndrome — than in a car accident.

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Diabetes experts who were not involved in the study cautioned that automated devices need far more rigorous testing to determine if they’ll be safe enough to become widespread.

“Quite a few things need to be addressed,” added Dr. David Harlan, chief of the diabetes division at the UMass Memorial Medical Center in Worcester. “The chances of the pump failing with two difference hormone infusions are great and it doesn’t remove constant diligence from lives of people with diabetes.”

The rate of type 1 diabetes — in which the body’s immune cells attack and destroy a healthy insulin-producing pancreas — has, for unknown reasons, been surging over the past few decades, with nearly 16,000 children under age 18 now diagnosed with the condition every year. (Type 2 diabetes, by comparison, is a more common condition, and tends to occur well into adulthood and has far more explainable causes, such as genetics, obesity, and a lack of exercise.)

In the new study, all of the study participants were closely monitored — adults were accompanied by nurses round-the-clock and the teens were in a summer camp for those with type 1 diabetes — to ensure that their blood sugar levels wouldn’t rise too high or fall too low, which could cause seizures or other complications.

The research found that adult patients with type 1 diabetes who used the experimental device had lower blood sugar levels overall than the control group while also spending 67 percent less time in a state of hypoglycemia.

Children who used the device experienced a 50 percent reduction in carbohydrate use to treat hypoglycemia, though they did not experience a significant difference in their blood sugar measurements. That’s likely because children who participated in the study were closely monitored even when they used their usual treatments, said Russell.

He and his colleagues presented their results Sunday evening at the American Diabetes Association meeting in San Francisco.

“The initial proof of concept is very strong,” said Dr. Guillermo Arreaza-Rubin, a director at the National Institute of Diabetes and Digestive and Kidney Diseases which funded the trial. “Parents of children with type 1 live in permanent fear and maybe this device can free them from that burden and increase the quality of life of those with this disease.”

A few other groups of researchers presented findings on similar automated devices at the diabetes conference, he said, which, like the device developed in Boston, are also about three or four years away from widespread use.

Christopher Herndon, 13, a study participant who tried the bionic pancreas last summer while at Camp Joslin in Charlton, said for the first time in his life he “felt steady the whole day” rather than shaky when his blood sugar levels dropped too low and “really talkative” when it was too high.

Despite using an insulin pump and continuous glucose monitoring device, which many diabetes experts consider to be gold standard therapies, the Newburyport teen said he has never been able to achieve the kind of blood sugar control that he had while using the bionic pancreas.

While his mother, Christina, often wakes him at 2 a.m. to have some juice if his blood sugar drops too low, he was never woken by his counselors at the camp during the five days he used the device.

 

Mark Lorenz for The Globe

Christopher Herndon said he has never been able to achieve the kind of blood sugar control that he had while using the bionic pancreas.

Colby Clarizia, another study participant, said he consumed three blueberry muffins for breakfast while wearing the artificial pancreas and was surprised to see how well the device worked. The 21-year-old from Amesbury also found it easy to use.

“Instead of measuring every carb in a glass of milk or serving of rice, I just had to input whether I was going to eat a large meal or small one,” he said.

Such a device, he added, would make it far easier for him to eat in restaurants where carbohydrate counts aren’t posted on menus.

The bionic pancreas automatically monitors blood sugar using a wireless glucose monitoring system that sends a signal every five minutes to an iPhone adapted with software. The iPhone app determines how much insulin to dispense — to make high blood sugar levels decrease — and how much of the hormone glucagon to dispense to make blood sugar levels rise; it also learns over time how to adjust the release of the two hormones based on input from the monitoring system.

Harlan plans to test the device in conjunction with Russell’s team in a large multicenter study launching this week that will have less rigorous monitoring. Participants will need to stay within an hour’s drive of the study site but won’t need to be accompanied by a health professional wherever they go.

“I think it’s an important step forward, but it’s going to be quite challenging to see whether this device can function safely and effectively without close supervision,” said Dr. Howard Wolpert, director of the institute for technology translation at the Joslin Diabetes Center in Boston, who reviewed the paper before publication. “An analogy I would present is that they climbed a flight of stairs but now the next stage will be like climbing a hill or even a mountain.”