Is There a Cure for Diabetes? A Look at the Remission Potential for Type 1, Type 2, and Gestational Diabetes
Is There a Cure for Diabetes? A Look at the Remission Potential for Type 1, Type 2, and Gestational Diabetes
If you or a loved one has been diagnosed with diabetes mellitus, one of the metabolic disorders characterized by blood sugar (glucose) that’s too high, you may be wondering if you have a chance of being cured. (1) Depending on what type of diabetes you have and how far the disease has progressed, you may be able to reverse course and return your blood sugar level back to normal — a state that would more accurately be called remission, as there’s always the possibility for relapse. (2)
Read on to find what medical experts and researchers say about the prospects of remission for the following forms of diabetes: type 1 diabetes, type 2 diabetes, and gestational diabetes.
How Type 2 Diabetes May Be Reversible Through Weight Loss, Diet, and Lifestyle Changes
Type 2 diabetes results from insulin resistance, which happens when your blood glucose (sugar) levels are too high because the cells in your muscles, fat, and liver have stopped responding well to insulin. Insulin is a hormone produced in the pancreas, which helps convert glucose into energy. At first, the body produces more insulin to compensate, but eventually it can’t keep up with the level of resistance. (3)
Type 2 diabetes is by far the most common type of diabetes, accounting for over 90 percent of cases. (4) It typically develops in people ages 45 and older, but it can happen at any age. A complex set of risk factors, including age, ethnicity, genetics, diet, and lifestyle are thought to be at play in those who develop the disease. (5) It’s also strongly correlated with obesity — in fact, up to 90 percent of people worldwide who have type 2 diabetes are overweight or obese. (6) (But it’s important to note that the majority of overweight and obese individuals do not develop diabetes.) (7)
The good news is that your diet, lifestyle (particularly exercise), and weight are things you can control, and with type 2 diabetes, remission is at least possible. “A lot of times patients think it’s like a futile effort, like whatever they do is not going to matter,” says Patricia Happel, DO, an assistant professor and associate medical director at NYIT College of Osteopathic Medicine in Old Westbury, New York. “What I try to do is empower them and educate them about what they can do to manage it, and hopefully, reverse it.”
One way of measuring blood sugar is through a hemoglobin A1C test, which measures how much glucose attached to the hemoglobin in your red blood cells, on average, over the previous three months. Below 5.7 percent A1C is a normal result. Prediabetes is a reversible state in which insulin resistance has pushed your blood sugar to between 5.7 percent and 6.4 percent. At 6.5 percent or above, you have diabetes. (8)
Dr. Happel says if your A1C is below 8.0, you may have a chance of returning to a normal blood sugar level, provided you make and maintain healthier eating, exercise, and lifestyle habits. As the A1C increases, it’s harder to return to a normal blood sugar level without medical intervention.Jordana Turkel, RD, CDE, at Park Avenue Endocrinology and Nutrition in New York City, also says she has seen people go into remission from type 2 diabetes if they act early enough. “Typically it’s done with a very-low-carb diet, a minimum of 150 minutes of exercise a week, with a combination of cardiovascular and strength training, as well as follow-up with both myself and the doctor.” Underscoring the fact that remission doesn’t mean the diabetes won’t come back, she adds, “Even if their numbers are in check, frequent follow-up is important.”
Turkel’s observation about the beneficial effects of a low-calorie diet is backed up by the results of a study published in December 2017 in the journal The Lancet, which looked at overweight and obese people with type 2 diabetes. It showed high levels of remission among participants who lost a significant amount of weight through a low-calorie diet. (9)
During the Diabetes Remission Clinical Trial (DIRECT), an open-label, cluster-randomized trial in the United Kingdom, antidiabetic and antihypertensive medication was withdrawn from 149 participants with type 2 diabetes who were then placed on a diet consisting of between 825 and 853 calories daily for three to five months. Forty-six percent of participants achieved remission, meaning that their hemoglobin A1C was less than 6.5 percent. The results were even more dramatic in people who lost 33 pounds (lbs) or more: Eighty-six percent of them achieved remission. (9)
Bariatric Surgery Could Also Play a Role in Helping Reverse Diabetes
Researchers have also observed remission in obese people who undergo bariatric (weight-loss) surgery, another route to losing a significant amount of weight. (10) A review and meta-analysis that appeared in the American Journal of Medicine looked at 621 studies that were published between 1990 and 2006, concluding that clinical signs of type 2 diabetes disappeared in about 78 percent of patients who underwent bariatric surgery. The average amount of weight lost was 85 lbs, or 55.9 percent of excess body weight. The procedures that netted the best results for weight loss and diabetes resolution were, in descending order: biliopancreatic diversion with duodenal switch, gastric bypass, and gastric banding procedures. (11)
Later research suggests that remission results may decrease over time. A study published in the New England Journal of Medicine in September 2017, which was a follow-up to an observational, prospective study that focused solely on gastric bypass patients, found this pattern. Among those who had type 2 diabetes before surgery, 75 percent were in remission after 2 years, 62 percent after 6 years, and 51 percent after 12 years. (12)
Gestational Diabetes Is Often Reversed After Pregnancy, but That Doesn’t Mean It’s Gone Forever
In pregnancy, a woman normally develops a certain amount of insulin resistance to ensure that there is enough glucose available to provide energy for her growing baby. That develops into gestational diabetes in up to 14 percent of all pregnancies in the United States. The condition is typically managed through diet and lifestyle modifications, although sometimes patients take oral diabetes medication or insulin. (13)
Fortunately, gestational diabetes usually reverses on its own after the child is born. But there’s a 30 to 70 percent chance of recurrence in subsequent pregnancies. Furthermore, half of all women with gestational diabetes will go on to develop type 2 diabetes later in life. “Sometimes the lifestyle stuff isn’t managed,” observes Happel, who recommends continuing with healthy eating and exercise habits even after the gestational diabetes has gone away. (13)
Type 1 Diabetes May Be Put in Remission via Cell Transplants and Artificial Pancreas Devices
Type 1 diabetes is an autoimmune disorder that usually appears in childhood or early adulthood. It’s caused when the body’s immune system attacks and destroys the insulin-producing beta cells. Without insulin, the level of blood glucose climbs too high, a condition known as hyperglycemia.
People who have type 1 diabetes must take injections to replace the insulin their body doesn’t make, as well as monitor and control their blood glucose level, on a daily basis for the rest of their lives. (14,15) “At present there is nothing that a patient can do to prevent type 1 diabetes,” says Joshua D. Miller, MD, medical director of diabetes care at Stony Brook Medicine in New York, who also manages a personal diagnosis of type 1 diabetes. There’s also no cure for type 1 diabetes. (16) Nonetheless, there have been developments in donor cell transplantation, as well as artificial pancreas technology, that have shown some promise in the quest for helping these people achieve remission.
To understand some of these developments, it’s important to know what the pancreas’s islet cells do. They make hormones that help the body break down glucose and use it for energy, including alpha cells that make glucagon (which causes the liver to break down glycogen into glucose and release it into the bloodstream) and beta cells that make insulin (which allow your body to use or store glucose). Together they help regulate your blood sugar. (17)
Islet Cell Transplantation
A growing field of treatment involves the transplantation of islet cells into a recipient with type 1 diabetes, in the hopes that they will begin secreting the hormones that allow the independent regulation of blood sugar.
Among the most established of this type of procedure is pancreatic islet allo-transplantation, in which the mature cells of a deceased donor are purified, processed, and transferred into a recipient. The islet cells begin to secrete insulin soon after transplantation, but insulin injections are usually needed until the donated cells are fully functional. After that, the recipient may no longer need to take insulin, or may need less of it. (18)
Yet the same autoimmune response that attacked the recipient’s original islet cells can strike the donated ones. Additionally, as with most organ donations, the recipient must take immunosuppressive drugs to stop the body from rejecting the transplanted islet cells, which come with significant side effects and can raise one’s risk of developing cancer and bacterial or viral infections. (18)
A report published in July 2012 in the journal Diabetes Care focused on islet transplantation recipients who were registered with the Collaborative Islet Transplant Registry. Of the 208 individuals who received transplants between 2007 and 2010, 44 percent had achieved insulin independence at three years after the original procedure (including those who had received subsequent reinfusions). (19)
Dr. Miller’s perspective is that despite limited successes, such procedures are “very expensive, fraught with complications and risk, and not at all ready for prime time in terms of widespread application.”
He is more optimistic about the potential for transplant procedures that use innovative, protective methods to tackle the problem of donor cell rejection. “What transplant scientists are working on is how to package beta cells in the body so that they remain viable in someone who receives them,” he explains.
For instance, Senorva is currently conducting a human clinical trial in the United States for a pouch that encapsulates donor islet cells to protect them, and is implanted under the skin, where it incorporates itself into the recipient’s living tissue and supports vein and tissue growth. (20,21)
People with type 1 diabetes who have hypoglycemia unawareness (a potentially life-threatening condition in which they are unaware the signs that their blood sugar has dropped too low) are being recruited to participate in the trial. This trial will include immunosuppressive therapy, but the company has said it intends to test the pouch without such medication in a subsequent trial. (21,22)
In a separate human clinical trial that already has more than two years’ worth of data, implantable pouch technology is being used to protect and support transplanted pancreatic progenitor cells that are derived from embryonic stem cells. After Viacyte’s VC-01 pouch is implanted into the recipient, the cells mature into islet cells that secrete insulin and regulate blood sugar levels. (23)
At the American Diabetes Association’s (ADA) 78th Scientific Sessions in June 2018, the study’s authors reported that islet cells have survived and proliferated within the VC-01 for up to two years. They said the device has protected the cells from donor tissue rejection or autoimmunity response, although in some subjects “a foreign body response to the device component” has been observed and further work is needed to address that. (24)
Artificial Pancreas Devices
Miller says that developments in artificial pancreas technology may hold the most promise for people with type 1 diabetes who wish to be free from insulin injections. (25)
“My definition of a cure has very little to do with preventing or reversing autoimmunity, and it has very much to do with how do you use and leverage technology to mimic the normal pancreatic function,” he says. Artificial pancreas devices — also known as closed-loop systems — employ insulin pumps, glucose sensors, and smart software to automate the delivery of the right amount of insulin at the right time for each individual.
In September 2016, the Food and Drug Administration (FDA) approved the Medtronic 670G Hybrid Closed Loop System for commercial use in people ages 14 and older, and in June 2018 that approval was expanded to include people as young as age 7 with type 1 diabetes. It measures glucose levels in the body every five minutes and automatically adjusts the delivery of insulin by either administering or withholding it. The Medtronic 670G includes: a sensor that attaches to the body to measure glucose levels under the skin; an insulin pump that is strapped to the body; and an infusion patch that’s connected to the pump with a catheter, delivering insulin. While the device automatically adjusts basal insulin (background insulin) levels, it is not fully automated in that users need to manually select bolus insulin (insulin pegged to meals) doses to account for carbohydrate consumption at mealtime. (26)
According to a research letter published in October 2016 in the Journal of the American Medical Association, a small, three-and-a-half-month-long, before-and-after study of people with type 1 diabetes showed that the Medtronic 670G kept users within their target blood glucose range — 71–180 mg/dl (milligrams per deciliter) — 72 percent of the time, versus 67 percent during the baseline period when they controlled their own insulin doses. (27)
Another hybrid closed-loop system, Insulet’s Omnipod, is in clinical trials. Data released on June 23, 2018, at the American Diabetes Association’s 78th Scientific Session from a five-day trial of 11 adults, showed the amount of time spent in the target glucose range of 70–180 mg/dl was 73.7 percent, versus 62.5 percent with standard insulin therapy. (28)
So there’s still room for improvement, and a number of companies are working on artificial pancreas devices that involve a greater degree of automation and delivery of additional hormones, such as glucagon. (29) “I think that we are on the precipice of having widespread access to closed-loop technology that will allow patients to lead a normal life, preventing complications from diabetes,” says Miller.