Type 2 Diabetes: Since 2001, more than 20 well-done, large, randomized and controlled trials have shown that a variety of inexpensive approaches can reduce the likelihood of developing type 2 diabetes in middle-aged and older individuals with prediabetes. Therapies that have been proven effective include modest weight loss (approximately 5% of body weight), modest physical activity (about 30 minutes of brisk walking 5 days of the week), and drugs that reduce the amount of insulin that the pancreas needs to produce. These trials specifically showed that fewer people who were given these therapies developed a diagnosis of diabetes every year compared to people who were given a placebo or who were not given these therapies.
The most common way of interpreting these trials has been that the therapies prevented diabetes.
However, people who received the active therapies could still develop diabetes – fewer people just developed it every year. For example, in one of the trials, about 4 out of 100 people who were given the therapy developed diabetes every year, compared to about 7 or 8 out of 100 people who didn’t get the therapy. Although these results could be interpreted as prevention, a more accurate description is that the therapies slowed or delayed the development of diabetes. This differs from the usual way that we think of prevention, in which the disease is prevented from ever occurring, not just delayed.
A similar situation now exists for type 1 diabetes. In a recent randomized controlled trial, people at high risk for developing type 1 diabetes (those with stage 2 type 1 diabetes) were either given a treatment (teplizumab) that affects the immune system or a placebo. Type 1 diabetes developed less frequently in those given teplizumab. Once again, the therapy didn’t stop the disease; it slowed it down.
These examples for both type 2 and type 1 diabetes demonstrate that new medical approaches are being developed that can slow diabetes progression. When drugs are given to reduce the development of a chronic disease, the most accurate way of describing it is that they are delaying rather than completely preventing the illness. We all expect that future advances may change this reality, as permanent prevention is what everyone is hoping for.
Here is a link to the randomized controlled trial mentioned in this article.
About the author
Hertzel Gerstein
Hertzel is an endocrinologist and professor at McMaster University who is in high demand as a speaker, advocate, and educator on diabetes-related topics. His research focuses on using large, international randomized trials to identify and test new ways of preventing type 2 diabetes, reducing serious health outcomes like strokes and death, and achieving type 2 diabetes remissions.