USF Study: Inexpensive Drug Could Cut Type 2 Diabetes Cases By 30 Percent

Aug 15, 2017

According to the latest figures from the Centers for Disease Control and Prevention, more than 29 million people in the United States have diabetes – many of them the Type 2 form of the disease. That's where the body doesn't produce enough insulin on its own.

But another 86 million adults have prediabetes, with up to a third at risk of developing Type 2 diabetes within five years.

Now while experts say a change in lifestyle, with a healthier diet and more exercise, would cut that number down, so could an inexpensive, generic prescription drug called metformin - a drug that is currently being used by only 0.7 percent of patients with prediabetes.

Dr. Nicholas Carris
Credit USF Health Communications

Dr. Nicholas Carris, an assistant professor at the University of South Florida College of Pharmacy, recently co-authored a study looking at the cost-effectiveness of the drug in the Journal of the American Pharmacists Association

(Note: You must be a member to view the full study.

Disclosure: Carris and his fellow authors have no conflicts of interest or financial interests in metformin or any other product or service mentioned in the article.)

Carris recently sat down with WUSF's University Beat to discuss the findings of the study. Here are some highlights: 

What does metformin do?

"Metformin is our first-line medication actually to treat Type 2 diabetes and it's been studied also to prevent diabetes. It's a generic medication, it helps lower blood sugar.

"For people with prediabetes, it can also help them lose weight -- just a little bit -- and that was found out in the Diabetes Prevention Program research study, which is what my study is based off of, and so in that study, after a little less than three years, metformin reduced patients' risk for developing Type 2 diabetes by a little over 30 percent." 

How cost-effective is metformin?

"There's the direct cost: If you have a prescription from your physician, you can take that prescription, you can pick it up for free at Publix. So the cost to the patient, it can be nothing in that direct sense.

"When you look at the overall cost, yeah, there's the cost of monitoring (kidney function) ... but here's the thing: If you also have hypertension or a long list of other conditions that may be seen with prediabetes, your kidney function -- how well your kidneys are working -- is going to be checked anyway.

"So when you're thinking about picking up a medication, for free, that can prevent diabetes, to me, it's a slam dunk. For people that don't have access to what I like to call 'a high-intensity lifestyle intervention,' and that's a term actually from the American Heart Association, where really making these hard-to-make changes in our lifestyle in terms of diet and exercise, and so, what I'm advocating is for an increased use of metformin to prevent diabetes, but in the right patients."

Who are "the right patients" and how can doctors identify them?

"They're already being identified and what we need to do is take action on them.

"Primarily we want patients under 60, so younger patients will have a better response in terms of (metformin) actually working to prevent diabetes; patients that are significantly overweight (obese with a Body Mass Index over 35); women that have previously had gestational diabetes; and then people that are trying to make those changes in their lifestyle, but they keep moving closer towards those thresholds of being classified in a diabetic range."  

Does metformin have side effects?

"There's a little bit of risk potentially for maybe an effect on Vitamin B-12, that's a really minor risk. Metformin's an old drug, it's been used a long time, physicians have a lot of experience with it.

"The one main side effect that we see with metformin is upset stomach, almost GI (gastrointestinal) distress, but the way we get around that, or at least make it as little of an impact as possible, is: Start on a low dose, take it with food, go up on the dose slow, if you have problems with it, we go back down on the dose, and that's why this isn't a medication that you take without a doctor watching over you."

Why aren't more doctors prescribing metformin and what can be done to change that?

"I think that's where we have a little bit of a disconnect. Some of it is a lack of awareness from primary care providers about what diabetes is ... maybe there needs to be some education to providers in that sense.

"Some of that might be that sometimes there's, in a (doctor's) office visit, a limited amount of time, and maybe there's bigger fish to fry on that given day and that can be a real thing and it's tough to address.

"The next step is to try and find ways to systematically get patients on it without increasing other costs. So we don't need to add any more screening costs, any more testing to the healthcare system because people are already being screened for Type 2 diabetes, we're already following those recommendations, the next step is increasing the action on the results if they're in the prediabetes range.

"And so, protocols, maybe within (the) outpatient system, working with physician groups, maybe protocols working with inpatient groups, particularly patients that already have heart disease, adding diabetes on top of heart disease is really detrimental.

"It's really identifying where can we get this started in a systematic way: Where can we bring people into the fold to where even if they can't do the lifestyle enrichment and even if they don't want to do the metformin, how can we keep checking on them, keep giving them the opportunity to make those changes? Or if they do develop diabetes, then, starting to treat that when it's early."