Transcription:
Management of Diabetes During Pregnancy and Gestational Diabetes

Melanie:  Welcome to Better Edge, a Northwestern Medicine podcast for physicians. I'm Melanie Cole and joining me Today is Dr. Emily Szmuilowicz. She's an Associate Professor of Medicine in Endocrinology at Northwestern medicine. And she joins me to discuss her research and clinical focus on the management of diabetes and gestational diabetes.

Dr. Szmuilowicz, thank you so much for joining us today. As we get into this, tell us a little bit about gestational diabetes. How prevalent is it? Tell us a little bit about the risk factors and assessing that clinical risk.

Dr Emily Szmuilowicz: Well, thanks so much for having me. Gestational diabetes is one of the most common complications of pregnancy. And depending on the criteria used to diagnose GDM, it affects anywhere from 6% to 25% of pregnant women. So it's quite prevalent and it's associated with increased risks of several serious conditions in both the mothers and the infants.

Some of the risks we most commonly associate with gestational diabetes are increased risk of what we call large for gestational age or excessive growth of the infant. That of course has potential consequences for the mother and baby, including increased risk of C-section, birth trauma to the mother or the newborn, and a number of other complications related to the mother and the baby. Those are the short-term risks that we think about.

Then of course, we know about long-term risks, which is that these women are at significantly higher risk for developing type 2 diabetes in the future, which isn't surprising since the pathophysiologic pathway of inadequate insulin secretion that leads to gestational diabetes is also underlying the later development of type 2 diabetes outside of pregnancy, so these are related conditions. And these mothers now know that they're at significantly increased risk of developing diabetes in the future. And then their babies are also at higher risk of developing obesity, abnormal glucose tolerance, and other features of a metabolic syndrome later in life.

So it really is a condition that affects not only the pregnancy itself, but then the mother and the baby's health for decades down the line. So it's a really important condition to think about, diagnose and treat, just because of its reach across so many decades of life in so many aspects of pregnancy and beyond.

Melanie: Well, thank you for that intro, doctor. And it is certainly a complex issue. Your clinical focus is on the management of gestational diabetes. Tell us a little bit about some of the current debates regarding detecting and treating gestational diabetes.

Dr Emily Szmuilowicz: As with every area of medicine, there's a lot of areas of debate. I would say that in the area of diagnosis or detection of gestational diabetes, there's an ongoing debate as to what is the best way of diagnosing it. Despite the fact that it's so prevalent, we still really don't have any universal agreement on how to best diagnose it.

There's two tests that are available most commonly. The one that's used most commonly in the United States and in our area is a two-step method. And by that method, what we do is all pregnant women between 24 and 28 weeks of pregnancy will come in for a standard non-fasting what's called a glucose blood test. They all get 50 grams of glucose and glucose levels are measured one hour later. Then only the women that have abnormal results on that test are going to go on and have a three-hour glucose tolerance test, which involves fasting and then measuring glucose at one, two and three hours after getting glucose. That's what we typically use here in the United States.

The other method that's available and is endorsed by several professional societies is a one-step method where all women just come in fasting, get glucose and we measure glucose fasting, and then one and two hours after glucose. And really the main difference between those two tests is that in the second one, the one-step method, women can be diagnosed with gestational diabetes by having only one abnormal resutl. Whereas on the first test that I mentioned, the one we most commonly use in the United States, women need to have two abnormal tests.

And so the reason that's really important, that sounds like a small thing, but the reason that's very important is that when we only require one test to be abnormal, one level to be abnormal, it leads to a marked increase in detection of gestational diabetes, meaning many more women are going to be diagnosed with GDM. So estimates are that we go up from about 5% or 6% to about 18%. And that's a tripling of the rates of the prevalence of gestational diabetes. And that's really important because we are screening an entire population of pregnant women. So you can imagine the scope when we triple, when we really increase the amount of women we're diagnosing with gestational diabetes.

So there's a lot of debate, what's the best test? You might say, "Well, I'd want the one that picks up more women," because we'll pick up more women with a more mild form of hyperglycemia and be able to help them and treat them. But I think the controversy comes from the fact that we don't have robust data showing us that diagnosing more women and treating these women with a more mild form of disease is going to improve outcomes. And that's what we really care about. We don't want to subject a huge segment of our population to more testing, more office visits, more expensive in terms of testing supplies and medications unless we know that that treatment is going to benefit them.

And so the jury is out. We really don't know which method is best. There's been a number of studies that have looked at this. There have been varying results, including one very highly circulated study that just recently came out that did not show benefit of treating these more milder forms and using the more sensitive tests. So, the debate continues and it's something that becomes very important when you're looking at a disease that's so common.

Melanie: So interesting, doctor. And while we're talking about various debates and even controversies, tell us about some of the new technologies, such as continuous glucose monitoring that play a role in gestational diabetes and are there some challenges? And also I've heard there are some barriers to the use of the self-monitored blood glucose, inconvenience, lack of timely and regular feedback. Tell us a little bit about what you've found as far as glucose monitoring goes.

Dr Emily Szmuilowicz: Sure. So continuous glucose monitoring, which is something that is becoming incredibly, thankfully, very widespread in the treatment of all forms of, for example, type 1 diabetes, and type 2 diabetes outside of pregnancy is now gaining increasing use within pregnancy as well. It has this type of technology in which women are able to receive glucose levels measured roughly every five minutes, as opposed to typically four to eight times a day where women prick their finger by the conventional method, just provides a wealth of data, that both the patients and the providers are able to use to guide treatment.

In pregnancy specifically, we now have very good evidence from clinical trials in women with type 1 diabetes that use of CGM or continuous glucose monitoring during pregnancy improves glycemic control as well as neonatal outcomes including one large child that showed that this led to reduced risk of large for gestational age babies, admission to the ICU, the NICU for the babies, neonatal hypoglycemia, et cetera. So this is a very powerful technology that is gaining increasing acceptance and use during pregnancy.

Specifically in terms of GDM, we have less data. The data is less robust. There haven't been as many studies evaluating this technology in women with gestational diabetes, meaning women who develop diabetes newly in the second and third trimesters of pregnancy. That being said, a recent expert guideline from the American Association of Clinical Endocrinology did recommend CGM for women who have GDM, who are taking insulin. It provides a number of benefits, including, like you said, more data available to guide therapy. It addresses issues of discomfort that patients often experience from having to prick their finger so many times a day. This device allows you to see those numbers automatically without having to repetitively prick the finger and cause discomfort.

One of the most exciting things about this type of technology, about CGM, is that it really empowers patients. It gives people an enormous amount of feedback about the types of choices and behaviors and activities that they do in their everyday life. For example, they'll find that a food that they may have thought would lead to large increases in glucose actually doesn't. And so they're able to return to that food and eat it more frequently. But the opposite is true as well, meaning a food that they thought would be quite good for the glucose levels, it turns out it's not. So it allows the woman to modify her eating patterns, to avoid the foods that lead to large glucose excursions, and to favor the foods that tend to be beneficial.

It shows them the benefits of activity and exercise. And likewise at the other end of the spectrum, it allows women to receive alerts for impending or actual hypoglycemia, which is a big concern for patients. A lot of women who are told they need to take insulin, they're worried about their glucose levels going too low at night. They've heard stories about hypoglycemia from family members or friends, and they're very frightened of it appropriately. And these monitors can often give women the sense of security that they need, knowing that if they go low overnight, this device will wake them up and wake up their partners as well.

And so it really gives women the empowerment and the security, to use the therapies that they need to treat the high glucose levels and to treat the diabetes during pregnancy. So we're very excited about it.

Melanie: So then give us your top recommendations, doctor, for your colleagues on how to best manage diabetes during pregnancy, when it's considered a high-risk pregnancy, what you'd like them to know also about referral.

Dr Emily Szmuilowicz: In our diabetes and pregnancy program, one very important thing to know about is that we co-manage with providers across the Northwestern system. Our clinic is housed within the maternal-fetal medicine division and one of the most exciting aspects and what I think one of the strongest benefits of this program is my strong collaboration with my colleagues in maternal-fetal medicine. It allows us not only to physically be co-located, but allows us to coordinate care in I think the most effective and efficient way possible. It's one of the biggest strengths of our program.

But outside of women who are considered high risk and who are followed in the maternal-fetal medicine division, I also collaborate in terms of management of insulin-treated diabetes with providers in practices across Northwestern and I work individually with them as well. So it really is a program that spans Northwestern, both in the central region and also in the community. So it's been a very exciting collaboration.

Melanie: Expand just a little bit more for us, doctor, before we wrap up about the diabetes and pregnancy program at Northwestern Medicine and what kinds of multidisciplinary team is involved in caring for these women.

Dr Emily Szmuilowicz: I'm really glad you raised that point because multidisciplinary care I think really is the key. For any complex condition, I think that's one of the most important things that we need to do is to involve members from different clinical areas and to coordinate together. And so, like I mentioned before, I collaborate closely with my colleagues in maternal-fetal medicine, including both physicians as well as Char Niznik, who is the backbone of our program, a very distinguished APN that works in the program together with me. We co-manage patients together and we work very closely, of course, with our colleagues, our dietician colleagues, because lifestyle modifications and medical nutrition therapy is of course one of the backbones of gestational diabetes and really all forms of diabetes in pregnancy.

And we all work together, and like I said, the physical co-location in maternal-fetal medicine is very important for those patients that are followed for obstetric care in MFM, because it allows them to do what we call a one-stop shop. They come on one day and see multiple providers who are coordinating together.

Melanie: And as we wrap up, leave with one parting piece of information for providers who are listening and counseling these patients because pregnant women are scared. And when they hear they've got gestational diabetes, that raises the nerves. So if they listen to their doctor, they get their lifestyle under control, can they still expect to deliver a healthy baby? And really give your best piece of advice to providers listening.

Dr Emily Szmuilowicz: We counsel women on that day in and day out. It's a lot of anxiety that women experience when they find out that they have this diagnosis. As I mentioned before, by the nature of the condition, many of these women have family members with type 2 diabetes or other forms of diabetes. And it can be a really scary experience to find out that this is something that affects you as well. And so we spend a lot of time counseling women about of course the risks, but the positive sides as well, which is that with effective treatment, we can dramatically lower those risks. And that is what we expect to see and we encourage our patients, that with this type of expert care that they can expect these types of wonderful outcomes for them and their pregnancies.

And I think that, you know, one of the things I would pass on to my colleagues is that you read some of the guidance, you might think that it's fairly standardized and one-size-fits-all in terms of how we treat these women. And I think one just really important piece of advice that I've learned in the years that I've been doing this is how important it is really just to listen to each individual patient that it can be quite nuanced, that there's so many different aspects that relate to treatment and are so pertinent to their treatment regimen, meaning it's not just the doses of medication. There's things like their activity levels, the other events leading up to changes in glucose levels, maybe a change in timing of medication related to work or family obligations or undercovering their carbohydrate intake because of the fears of hypoglycemia, et cetera. So there's so much that we can learn from our patients. And the one thing that I've learned, one of the things that I've learned in managing gestational diabetes and diabetes in pregnancy is that it is just so important that we listen to each patient, listen to each woman and engage them in care so that we can develop a care plan together.

Melanie: What an informative episode. Such a great guest you are, Dr. Szmuilowicz. Thank you so much for joining us today.

To refer your patient to the diabetes and pregnancy program at Northwestern Medicine, please visit our website at nm.org to get connected with one of our providers.

That concludes this episode of Better Edge, a Northwestern Medicine podcast for physicians. For updates on the latest medical advancements and breakthroughs, follow us on your social channels. I'm Melanie Cole.