Hybrid Closed Loop System

Type 1 diabetes is a tough disease for pediatric patients and their parents to live with. At Stony Brook Children’s Hospital, pediatric endocrinologists are making these families’ lives easier and healthier, by offering innovative treatments as soon as they become available.  

One innovative device that Jennifer Osipoff, MD, FAAP, Assistant Professor of Pediatric Endocrinology at Stony Brook Children’s,  calls an “exciting step forward” in treating her young diabetic patients is the MiniMed 670G insulin pump with Guardian Link 3 sensor.  

The MiniMed 670G system is the first technology to automatically adjust a patient’s insulin delivery. The hybrid closed loop system consists of a sensor (placed under the patient’s skin) that communicates wirelessly with a portable insulin pump worn by the patient.  

The system’s continuous glucose monitor tests the patient’s blood glucose 288 times a day (approximately every five minutes) and, when used in “auto mode,” adjusts the background, or basal insulin, without input from the wearer. It can predict when blood sugar will fall, and give less insulin to prevent the level from dropping too low.  The system can also give “micro-boluses” of insulin when the glucose levels are too high, to help bring the user’s blood glucose back into target range.  

Type 1 diabetes is an autoimmune disease that occurs when a person’s own body attacks their pancreas. The pancreas loses its ability to make insulin, a hormone essential to moving glucose out of the bloodstream so cells can use it for energy. Researchers have yet to pinpoint a definitive cause of Type 1 diabetes, and there is no cure. But we know that stabilizing blood glucose levels as early on as possible can prevent serious medical complications from developing later on.  

Thomas Wilson, MD, Division Chief of Pediatric Endocrinology at Stony Brook Children’s, said Type 1 diabetes “demands a huge amount of effort on the part of patients to lead normal lives. But the technology has come a long way. We can now manage their blood sugars in real time. They can keep their blood sugar in control much better than 20 or 30 years ago, so that should have a much better impact on the progress of the disease.”   

“We’re getting better and better at treating,” he said. “And as we’ve gotten better at identifying people likely to get diabetes, I think at some point we might be able to prevent diabetes from happening.”  

number one Five-year-old Nadia McKee, a Stony Brook Children’s patient, is one of the first children in the country to be put on the MiniMed 670G system. For her and other kids younger than 14, Dr. Osipoff is prescribing the pump “off label.” The U.S. Food and Drug Administration approved the device last year for patients age 14 and older, but doctors are allowed to prescribe it off label for younger age groups.  

“I’m most excited to use the system in my youngest patients. I have several patients younger than 2 years old who are unable to express their symptoms of hypoglycemia (low blood glucose.) Hypoglycemia can cause loss of consciousness or seizures so it’s obviously a feared side effect of insulin delivery,” Dr. Osipoff said. “When their blood glucoses are too low, toddlers can’t just say, ‘Hey Mom and Dad, I’m feeling a little shaky over here. I need something to eat.’  Automatically adjusting insulin to help prevent these episodes will greatly enhance these families’ quality of life.”  

Dr. Osipoff said the device’s auto mode is also good for teens, who might be more interested in the usual adolescent pursuits than checking blood glucose levels.  

“Parents can trust this system. They can just say to their kid, ‘Are you in automated mode?’ instead of nagging them about checking their blood sugar,” she said.  

The division of pediatric endocrinology held its first Diabetes Technology Night at Stony Brook Medicine’s new Advanced Specialty Care facility in Commack. The gathering was a fun way for kids to try out many pumps and sensors on the market. With close to 50 families in attendance, it was a great meeting place for mutual support. More events are already being planned.  

sistersNadia McKee, wearing a big smile and a pink party dress, was at Technology Night with her mom Daniela and dad Rob. At Stony Brook Children’s, “Nadia has the best pediatrician in the world in Dr. Leslie Quinn, and Dr. Osipoff is an amazing combination of empathy and knowing about the latest technology,” Daniela said. Nadia’s parents said having access to ever-evolving diabetes management helps Nadia keep her blood glucose at appropriate levels, even when she’s outside playing or at a birthday party.  

Keri and John Armentano were also at Technology Night, with their 7-year-old fraternal twins Connie and Maria and 6-year-old Rose. To have all three siblings diagnosed with Type 1 diabetes was “a surprise, to say the least,” said Keri. The girls use the DexCom continuous glucose monitor with an Omnipod insulin pump. “Their ability to use and operate the technology allows them a level of independence,” their mom said.  

Rose demonstrated how Stony Brook Children’s staff taught her to swab her finger with alcohol, do a finger stick, touch her finger to her glucose monitor, and keep her blood sugar level right where it should be. How does it make her feel, to handle that process all by herself? “Sometimes brave. Smart, too,” she said. Her sister Maria had a message for other kids with Type 1 diabetes: “Take care of yourself. Try not to be scared of the pump.”  

Daniel Aponte and brother high five each otherEight-year-old Daniel Aponte was mingling at Technology Night with his mom, Meredeth, and dad, Danny. Daniel was diagnosed just before Thanksgiving four years ago. When the family’s primary care doctor, Dr. Katherine Wightman from Stony Brook Medicine’s Department of Family Medicine, saw Daniel’s symptoms, she told his parents to bring him directly to the Emergency Department. Instead of sitting down to a Thanksgiving feast like they expected, they spent the holiday in the hospital.

Daniel Aponte Now Daniel uses the MiniMed 530G (manufactured by Medtronic, the same company that makes the latest pump) and will upgrade to the 670G later this year. Moving up to the 670G means his parents will be able to sleep through the night. Now they are up until 2 or 3 a.m., three or four nights a week, monitoring Daniel’s fluctuating levels of blood glucose. The 670G will sense his highs and lows and automatically give him the right insulin dose.  

“The pump will be watching him for us,” Danny says. As for Daniel, he’s taking on more and more responsibility for managing his health. “I look and see if I can calibrate myself, and I do my own insulin dose,” he said.  

Clinical trials are underway at Stony Brook Children’s, to test the efficacy of technologies used in the treatment of Type 1 diabetes. A post-marketing trial examined and expanded uses of the new 670G’s predecessor, the 530G, and now the manufacturer plans a post-marketing clinical trial at Stony Brook for the 670G.  

“The technology available to us at Stony Brook Children’s is always improving and making this disease easier to manage,” Dr. Osipoff said.