While type 2 diabetes isn’t directly caused by obesity — there are plenty of obese people without diabetes, and many thin people with type 2 — there is undeniably a connection between the two conditions. Insulin resistance — when your body becomes less responsive to the effects of insulin, the hormone that lets your body’s cells use glucose from your blood as fuel — is one of the conditions that make up metabolic syndrome, along with obesity, high blood pressure, abnormal cholesterol and triglyceride levels, increased blood clotting, and increased inflammation. Metabolic syndrome greatly increases your risk of developing type 2 diabetes, as well as cardiovascular disease.
In practice, this means that many people with type 2 diabetes are obese, even if one condition doesn’t cause the other. But losing extra weight can have major benefits if you have diabetes. According to the American Diabetes Association, losing just 5% to 10% of your body weight can substantially improve your blood glucose control, along with the other markers of metabolic syndrome.
To get cutting-edge diabetes news, strategies for blood glucose management, nutrition tips, healthy recipes, and more delivered straight to your inbox, sign up for our free newsletter!
But despite its benefits, achieving this level of weight loss is difficult for many people — and often requires lifestyle interventions that may be sustainable in the context of a study, with regular guidance and coaching, but aren’t quite so easy to achieve on your own in the real world. So any drug that helps people with type 2 lose weight could prove to be enormously helpful in reducing the burden of both diabetes and heart disease.
In this context, the results of a new study — showing substantial weight loss from a drug in people with type 2 — may demonstrate a game-changing path forward in treating obesity in the context of diabetes.
Less body fat, lower glucose levels
The study, published in the journal JAMA Network Open, involved 75 people with type 2 diabetes and a body-mass index (BMI, a measure of body weight that takes height into account) between 28 and 40 — meaning they were obese or near-obese. Each participant was randomly assigned to take either bimagrumab — a monoclonal antibody (a type of biologic drug) developed by Novartis — or a placebo (inactive treatment) for 48 weeks. The real or fake treatments were given by intravenous (IV) infusion every four weeks. Both groups also received diet and exercise counseling.
At the end of the nearly yearlong study, there were dramatic differences between the bimagrumab and placebo groups. Those in the active drug treatment group had lost an average of 20.5% of their body fat mass, compared with just 0.5% in the placebo group. They also increased their body’s lean mass by 3.6%, compared with a lean mass loss of 0.8% in the placebo group. The treatment group lost an average of 9.0 centimeters (3.5 inches) in waist circumference, compared with just 0.5 centimeters (0.2 inches) in the placebo group. Overall, members of the treatment group lost an average of 6.5% of their body weight, compared with 0.8% in the placebo group.
There were also greater improvements in blood glucose control in the treatment group, with an average drop in A1C (a measure o long-term blood glucose control) of 0.76%, compared with just 0.04% in the placebo group.
A new treatment strategy?
The researchers concluded that using a drug such as bimagrumab to block the body’s activin type II receptors, which stimulates skeletal muscle growth, could be a new and important way to treat obesity in the context of diabetes. This is especially true, they write, because many people with diabetes aren’t good candidates for bariatric (weight-loss) surgery, and because the risk profile of bimagrumab is better, in many ways, than surgery.
It remains to be seen whether treatment with bimagrumab could lead to even more weight loss, or fat mass loss, if it were combined with an active lifestyle program instead of just counseling. But even if it leads to weight loss of just 6.5%, this drug could have significant benefits in reducing the burden of diabetes complications and cardiovascular disease.
One potential downside of bimagrumab is the expense involved, since infusions of currently approved biologic drugs tend to cost thousands of dollars. But if the cost savings from improved health outweighed the treatment costs, insurance companies could be eager to cover even a relatively expensive treatment for obesity in people with type 2 diabetes.