Closing the Loop in the Management of Type 1 Diabetes
Hello, and welcome to season two of Diving Into Diabetes, the podcast where we explore the latest advances in best practices on individualized diabetes care. I'm your host, Dr. Ron Goldenberg, and our topic for discussion today is overcoming the challenges of living with type 1 diabetes. With me on the program today is Dr. Bruce Perkins. Dr. Perkins is the director of the Leadership Sinai Center for Diabetes at the University of Toronto. He's a clinician scientist with extensive experience doing cohort studies and trials for important issues in type 1 diabetes. He's dedicated to patient-oriented research and has lived with diabetes himself since he was a teenager. So welcome, Dr. Perkins. I'm very excited to have you on today. Ron, thank you so much. I'm excited to be here as well. Great. So let's get started, and we're going to discuss some important issues and challenges related to living with type 1 diabetes. So let's start based on your experience. What are the typical challenges faced by those living with type 1 diabetes today in 2023? Yeah, that's a great question. It turns out there's a lot of them. So if I were to categorize them, I mean, the first one is the challenge of just, frankly, getting by day to day and managing reasonable blood sugar control. So an aspect of this is that we have a lot of tools that can help better insulins, better ways of measuring blood glucose, of delivering insulin, but somehow getting through the day, managing all of these choices, and this huge amount of burden involved in getting through the day, I would say is the first major challenge. The second is that there are dangers with type 1 diabetes. Like type 1 diabetes is a fatal disease. People can die from it, from insulin lack or relative insulin lack. We call that diabetic ketoacidosis. And it's something that gets forgotten. And there are still five to seven out of every hundred people with type 1 diabetes each year who are going into diabetic ketoacidosis. And to me, that's a fundamental issue that we have to bring to the forefront. And then the final thing is like everyone with any form of diabetes, we need to do all those things to prevent complications, prevent cardiovascular disease, which people with type 1 are at an extremely accentuated risk of. And those things are often kind of forgotten at the cost of getting by day to day with blood sugar control. So thanks. That's a great introduction to our topic, but I hate discussing the negative side of diabetes because things are so optimistic these days for healthcare providers looking after individuals with type 1 diabetes and especially for individuals themselves. So, you know, we've come a long way in the hundred years or more since insulin was discovered. And there's been incredible innovation in the field, particularly related to glucose monitoring, like you said, and insulin pumps. So let's take a deeper dive. And have you reviewed with us very briefly how things like continuous glucose monitoring and insulin pumps have improved the lives of individuals living with type 1 diabetes? Yeah, so they definitely, both of these have. So the first component is the insulin pump. You load a little device with fast-absorbing insulin, and then it gets delivered at an hourly rate. It's delivered at an hourly rate, but every five minutes. And that gives someone basal insulin, the amount of insulin they need for when they're not eating. But then when they eat a meal, they need to take a bolus of insulin. So it's a way of taking fast-acting insulin, one alone, and delivering it for all of the insulin needs, basal as well as bolus for food, and also bolus to correct high sugars. So the second piece is a continuous glucose sensor. Now we have these great devices inserted with a needle that goes in and out and leaves a little filament. And it kind of, samples the glucose and the interstitial fluid under the skin, which is a pretty good proxy for blood sugar. And so then someone can look at this and they can make decisions about their insulin. But it's a perfect opportunity to have the glucose data go directly to the pump or to an algorithm that can then, that can be in a little computer or generally on a phone or a device that looks like a phone, that can then decide on adjusting the basal insulin or adding on some of these correction doses if the sugar's running too high. So the first example of this was a situation where if someone's going low, for example, during the night when they're sleeping, if they don't respond to an alarm, it can just shut off insulin for a couple of hours and then turn it on again. That was called low glucose suspension. It did a great job of preventing hypoglycemia. But why on earth wouldn't we have it work on the opposite end if someone's climbing in blood sugar, that it's starting to give more basal insulin, but on top of that, more importantly, correction doses of insulin? So these systems now exist. That's the concept of what we call automated insulin delivery. But I would just emphasize, Ron, that it sounds magical, like, oh, put this on and all my sugars will be perfect. It's just a tool to help adjust basal insulin and give some correction doses of insulin. It's not covering food. The person still needs to kind of count their carbs or estimate their insulin dose for food well and give that dose before they start eating. So the other term for automated insulin delivery is a hybrid closed loop because the pump is managing aspects of the insulin delivery, but the person is managing also aspects of it, the food boluses. So it's the hybrid of the two approaches. I can imagine now Frederick Banting, if he could view what was happening today with the delivery of insulin compared to the crude way it was done back in the 1920s, I think he would be very impressed. And I think our patients live with great fear of hypoglycemia. And I think these tools have probably not eliminated the fear, but dramatically improved that fear because several years ago, there was a survey of patients with type one diabetes and they feared hypoglycemia more than developing blindness from their diabetes on that term. So I think with that in perspective, these new tools have dramatically helped. But do you think Dr. Perkins that everybody with type one diabetes should be using CGM and or hybrid closed-loop pumps? Yeah. So my philosophy on this is that I wish that everyone with type one diabetes could have the opportunity to make that choice for themselves. So we have good injected insulins now. And you know, some people somehow manage pretty well on finger stick blood sugars, just checking before each meal and at bedtime plus some extras. And they do well and they're leading very functional, happy lives. And so if someone is doing well on those, it seems really tough to now push them onto therapies that they may not prefer to be on. So for example, to be on a pump and a sensor means you have to wear these devices that can feel weird. It can look weird to you. Some people lose confidence being around other people that it's a sign of their condition. So to me, it's a choice that I wish everyone had. And it's a choice that I kind of push people into if they are struggling. But there's a proportion of people who somehow or the other manage well on more vintage tools. And I would never push someone who's meeting their goals and living life well to take on another therapy that they may not want to. I hope that made sense the way I described it. I think so. And even though patients are still on kind of old-fashioned multiple daily injections, the newer analog insulins, especially the new basal long-acting analogs have made hypoglycemia less of a problem for those with type one diabetes still on injections, and using multiple injections with CGM seems to be very helpful as well. Exactly. If you're going to choose one of those pieces of technology, the glucose sensor, the CGM makes the most sense because we do have great injected basal insulins and other insulins now, you're right. But I guess the key message to our listeners is it's fantastic to have all of these options and certainly personal preference and that conversation between the patient and the healthcare provider is important. But it's nice to have these options to improve the lives of individuals living with type one diabetes. So moving on, you have many patients with type one diabetes. Can you give us some key pearls that you typically provide to your patients that help them stay healthy when living with type one diabetes on a day-to-day basis? Yeah. So even though a healthy lifestyle, committing to exercise most days and eating a healthy diet that doesn't have the high glycemic index foods, like higher, healthier foods, even though that's not a cause of type one diabetes, it helps to establish that sort of foundation to add on all these other things, whatever insulin regimen and how it's administered. Somehow it never goes well unless someone is making a great commitment to a healthy lifestyle, diet, and exercise. So that to me is a key thing. It's not the only treatment, but without that foundation, it's tough to move on and do well with other aspects of therapy. So that's the first thing. The second thing is that I feel like it always pays for someone with type one diabetes to just understand their insulin regimen and what it's doing. When you take a fast-acting insulin that is not acting immediately, it only peaks in the blood at an hour to an hour and a half, even though some of it gets in immediately and it lasts for four hours. Understanding that understanding how their basal insulin works, getting into some of those details always pays off because when you're living with it and trying to make a decision, oh, I'm about to get in the car, but I have this much insulin still acting and it's dropping, I can make a decision or I'm about to run out and do groceries, but my blood sugar is at this level. Understanding the previous doses of insulin and how long they act helps someone kind of get through their day magically than if they are just making big assumptions about how their insulin works. So those are two kinds of key things that I need for people with type one diabetes to understand. There's this terminology or phrase in medicine, see one, do one, teach one. And I think living with type one diabetes is a good example of that. You have to live with it and experience it and then learn from your experiences. Type one diabetes is a condition looked after by a whole slew of healthcare professionals and family physicians are involved and certainly diabetes educators and nurse practitioners. Any advice you would give to these individuals, particularly related to caring for people with type one diabetes? Yeah. So I mean, I would promote that two kind of things I just mentioned, a healthy lifestyle, making that commitment, and understanding your insulin, like even little bits at a time over time. But specifically, to a primary care physician who may not understand, let's say these devices and exactly how to interpret them, I would say don't be intimidated by them. When you have a person living with diabetes in front of you who's wearing a pump or wearing a sensor, say, show me your basal insulin, show me your food bolus, your correction bolus. How does it work? Show me your trends in glucose, because trust me as a family physician, even if you feel intimidated, let's say by a glucose report, you intuitively understand it. It's not you that's the problem. It might be the report. And just looking at it, you will understand. So my advice is do not be intimidated by these things just because they're technologies. They are simply meant to show us blood sugars and help us understand them. And they're simply meant to provide insulin. So you have the tools necessary to understand these things. So take those advantages when you have someone with type one in front of you. And I think that's great because more and more healthcare providers are going to have to be aware of these newer tools like CGM and insulin pumps as they get utilized more and more. Yeah. And Ron, I would say you would hope that these would just be plug-and-play. You just put someone on this device and it manages their diabetes, but it's a long way away until it does that. The person has to be engaged and therefore their team, including their family doctor, needs to generally understand this and help coach them through it. Excellent. So finally, you're at the forefront of research in type one diabetes. You've done some excellent studies over the years, but I'd like you to look to the future for a second and tell us what you think will be the most important new development in type one diabetes care in the coming years. All right. So I'm going to leave the technologies, even though there are a few things to refine that, but you already get it. They're going to be miniaturized. They're going to be better. They're going to have better algorithms. They're going to use machine learning and personalization, but just imagine that and put that aside. The next is someone diagnosed with diabetes. The next is someone who's not yet diagnosed with diabetes. We now have a therapy. It's an immune therapy. The specific drug is called teplizumab. It's been approved in the US anyway for people who are at risk of developing type one diabetes, and it has a biological effect. It doesn't completely negate getting type one, but it delays it by over two years, and that's a starting point. It means that we can figure out better ways to dose it to prevent it for longer, but to me, more importantly, because it is tough predicting who out there is going to get type one diabetes, to me, more importantly, it gives us a new wave of confidence to investigate this drug and similar drugs in people who are at the moment of being diagnosed with type one, that kind of immune emergency when they're losing insulin-producing cells. To me, that's one big area, immunotherapy for new-onset type one diabetes. The second is the cell-based therapies, which now it's getting more and more exciting. We've got stem cell-derived islets. Islets are the little clumps of cells that make insulin and also glucagon and the other hormones, somatostatin, that are now in human trials, and it's already common knowledge that in one of these studies, someone has been insulin-independent for well over a year from receiving an infusion of these cells. Now, the trick here is that that person needs immunosuppression medications, which isn't the easiest thing, but they are getting better and easier to take. So, it's a solution that there's no question in my mind we're going to be using clinically at some point in these next years. Maybe not for everyone with type one. I think eventually we'll be able to design these stem cells that can be replaced for everyone. And I'll leave it there. Maybe I'll just do a couple of other things. Type two diabetes, there are transformational drugs that have helped manage blood sugars in people with type 2 diabetes and also decrease heart disease and kidney disease and heart failure risks. We are doing more and more research to understand how these could be applied in people with type one diabetes on top of their insulin to make blood sugar smoother, but also help them prevent these terrible complications as we are doing a good job in people with type two diabetes. So, that's another area of research that I think we need to focus on. Great way to end our podcast for today. And if I could just recap for what you eloquently reviewed with us today is that there's still an incredible burden for living with type one diabetes, but with advanced and newer technologies over the years, like continuous glucose monitoring and newer insulin pumps, we've come a long way to improve the lives of our patients with type one diabetes. But there's even more room for optimism looking into the near future for preventing type one diabetes, intervening to prevent complications, and perhaps even curing type one diabetes in the future. So, thank you, Dr. Perkins, for joining us, and thanks to all for listening to this latest installment of the Diving into Diabetes podcast series. We hope you enjoyed our discussion of overcoming the challenges of living with type one diabetes. Don't forget to subscribe to our podcast on iTunes, Spotify, or Google Podcasts and stay tuned for new releases.
