Sometimes, when I’m bored at Sunday breakfast, I pretend I’m Steve Harvey and subject my relatives to a round of medical Family Feud. Here’s a sample question: “According to 100 people surveyed, what image comes to mind when you think of diabetes complications?” Forced to play along, my family offers these responses: “Amputations! Blindness!” Neither answer surprises me, not because I’m a doctor, but because they’re the first images that come to my mind, too. What does surprise me, however, is how seldom I hear the answer “Heart disease.”
Cardiovascular disease is the leading cause of death in type 2 diabetes.
Every day I see at least one patient in the office whose heart disease is a direct complication of diabetes. That’s because many heart problems are caused by atherosclerosis – blockages in the arteries that supply the heart. And, put simply: sugar is toxic to blood vessels. Please don’t counter with “Oh, but the body needs sugar.” I know. It also needs cholesterol, fat, and salt. But, as our grannies kept reminding us, “Too much of a good thing …”
So, do you have diabetes? How old are you? Because here are a few grim statistics that might make you forget about cholesterol, fat, and salt for a minute: Having a history of diabetes at age 60 can shorten your life by 6 years. Having both diabetes and a heart attack by age 60 can shorten your life by 12 years. When you fantasize about retirement plans and hear these awful numbers, it makes you want to learn some things about sugar.
Type 2 diabetes is a condition in which your body doesn’t metabolize blood sugar properly. This leads to elevated blood sugar. There are a few ways to diagnose diabetes, all involving blood sugar measurements – either fasting, randomly, or the hemoglobin A1c – abbreviated HbA1c or, simply, “A1c”.
Hemoglobin is a red blood cell protein that carries oxygen. Turns out sugar also attaches to hemoglobin, in proportion to the sugar levels in blood. Because the life span of a red cell is 120 days, the HbA1c level is a good indicator of your 3-month average blood sugar. A normal level is below 5.7%. Above 6.5% means you probably have diabetes.
Now, here’s another Family Feud challenge: “Name a medication that lowers blood sugar!” If you didn’t slam the buzzer and shout INSULIN you’re not going home with the cash. But did you know, for type 2 diabetes, there are actually dozens of sugar-lowering medications? Some are cheap. Some are not. I Googled it, and after I had tallied over 30 drugs, either alone or in combination, I got bored, and went to check my Twitter account. The point is, your doctor has a huge array of choices to lower your blood sugar.
But now, hear this: all diabetes drugs may lower blood sugar, but they don’t all reduce your chances of having a heart attack. In fact, some (rosiglitazone, or Avandia, comes to mind) actually increase the risk. I know, it makes no sense. Diabetes causes heart attacks, and you would think that lowering blood sugar by whatever means necessary would reduce that risk. Not so. That’s why, about 10 years ago the FDA told pharmaceutical companies that no more diabetes drugs would be released just because they lower blood sugar – from now on, they also had to prove the new drug wouldn’t predispose diabetics to a higher risk of heart disease. So, when Jardiance (empagliflozin) came along a few years ago, the researchers set out to prove it could lower blood sugar without causing heart problems. Here’s what they found:
In the EMPA-Reg Outcome trial (Empagliflozin cardiovascular outcome event trial in type 2 diabetes mellitus) patients with type 2 diabetes who had a heart attack, a bypass, or an angiogram showing multiple coronary artery blockages, received either Jardiance (empagliflozin) or placebo. After 3 years, and to everyone’s shock, not only did Jardiance not cause heart problems, it resulted in a 38% lower chance of cardiovascular death.
That may sound like just another boring statistic to you, but in the medical world it made time stop. Jardiance saved lives. Pharmaceutical execs were high-fiving each other in boardrooms. Diabetologists packed their bow ties in preparation for a new round on the lecture circuit. Cardiologists looked up from their journals and marveled, “Hmm, another intervention with mortality benefit.” Family doctors sighed and wondered whether specialists who had already hijacked cholesterol and hypertension treatment would now be managing blood sugars, too. What, everyone wondered, was this Jardiance all about?
Jardiance is an SGLT2 inhibitor that reduces blood sugar by preventing renal glucose reabsorption and increasing renal glucose excretion. In plain English, you pee sugar out. That’s wonderful because it improves your HbA1c. But it turns out Jardiance’s ability to prevent heart attacks is only partially related to sugar lowering. Because it makes you pee sugar (there go the calories, into the toilet bowl, hurrah!) you lose a little weight. To add to that, along with sugar, you pee out water and salt, and that lowers blood pressure, another bonus for those with hypertension.
Jardiance is not the only diabetes drug that reduces cardiovascular events: the old tried-and-true metformin (Glucophage) and the newer liraglutide (Victoza), semaglutide (Ozempic) and canagliflozin (Invokana) also have cardiovascular benefits. But Jardiance is the first diabetes drug shown to reduce cardiovascular mortality in persons who already have atherosclerosis. That’s big. And the positive studies keep appearing – one last year suggested that Jardiance can be expected to extend lifespan by 1 – 4.5 years; another demonstrated reductions in both kidney disease and heart failure. One thing is clear:
For persons with type 2 diabetes and heart disease, it doesn’t just matter that you lower blood sugar, it matters how you lower it.
Of course, no drug is perfect. Jardiance’s side effects include dehydration, low blood pressure, and genital infections. That means you must practice good perineal hygiene, or as your mother might say, “keep yourself clean down there”. Regardless, at this point the evidence is so convincing, that the American Diabetes Association, in their 2019 Standards of Care, recommends that for type 2 diabetics with heart disease – after lifestyle modifications and the old tried-and-true metformin – treatment should include a medication that both lowers blood sugar and improves heart health. Now there’s an answer I like.
Some final thoughts on treating diabetes and heart disease …
Will your cardiologist now be taking over the management of your diabetes? I doubt it. But more than ever, medical disciplines are overlapping when it comes to the care and prevention of chronic diseases. Cardiologists need to know what kidney specialists, weight-reduction specialists, and diabetes specialists are doing. We also need to know if the orthopedic surgeon gives you Mobic, Advil, Arcoxia, or any other anti-inflammatory that predisposes to salt and water retention which can aggravate high blood pressure and heart failure. And the family doctors need to know what all those specialists are up to (I do not envy them all the texts, emails, phone calls, and letters they must wade through). The thing is, as regards diabetes, for years there’s been this vague notion that it doesn’t much matter which drugs you use to lower blood sugar, as long as your HbA1c is at a reasonable level. Now we know that’s not true. For diabetics with heart disease, it does matter, and everyone needs to be on the same page.
So, let’s start with this: if you have type 2 diabetes and heart disease, take a moment to line up your pill bottles. See whether metformin (Glucophage) is amongst them – for most, that’s a good thing. Then, if you’re on additional diabetes pills, learn the names. Do your other diabetes medications have heart-protective properties? Not sure? Ask your doctor. I think everyone would agree, if you have a choice between a medication that just gives you a nice HbA1c (which is wonderful) and a medication that gives you a nice HbA1c and reduces your risk of cardiovascular death, you should opt for the one might save your life. Finally, I cannot finish without a reminder that diet, exercise, weight loss, and lifestyle modifications will always be the mainstay of treatment for type 2 diabetics, whether you have heart disease or not. And sometimes lifestyle interventions are enough to keep you off pills all together, or at least minimize the number you have to take.
For more news on the latest developments in cardiology, visit www.ShaneMarshallMD.com, subscribe to the free newsletter The Annals of Cardiology, and follow Dr. Marshall on Twitter @ShaneMarshallMD.