People with diabetes are two to four times more likely to have a vascular “event,” such as a heart attack or stroke. What can you do to prevent this? Although there is often a large focus on controlling blood sugars when we think of diabetes management, there are other areas, in addition to glucose control, that play a big part in reducing complications.
There are two types of risk factors for vascular disease: non-modifiable (this means that you can’t change them) and modifiable (this means that you can change them). The more risk factors you have, the more likely you are to have a vascular event. You can’t change your gender (men have a higher risk of a heart attack than woman) or your parents (you are at greater risk if one of your parents had a heart attack before the age of 60). You can’t change your age (your risk increases with age) or your nationality (South Asians have a higher risk).
You can, however, make a difference by changing your modifiable risks, such as quitting smoking, getting exercise, attaining and maintaining an ideal body weight, taking care of your diabetes and taking medication to lower blood pressure or cholesterol, if recommended.
Over the past few years I have written various blogs about preventing heart attacks and stroke in people living with diabetes. This blog will summarize the steps that people can take to live a long and healthy life with diabetes, and reduce their risk of having a vascular event.
A: A1C at target
One very large study in type 1 diabetes (the Diabetes Control and Complication Trial) showed that if your A1C is 7% (vs. 9%) over time, your risk of heart attack is reduced by almost 60%. This is especially true if blood glucose targets are reached early in the course of diabetes. This is known as “metabolic memory:” even if the people with an A1C of 7% and those with an A1C of 9% after the study ended had the same A1C of 8% for 10 years, later on, those who initially had an A1C of 7% continued to have a reduced rate of heart disease.
For type 2 diabetes the link is not as direct for just glucose control alone. However some studies – especially in people who are newly diagnosed – have shown that there is a consistent 15% reduction in heart attacks for those whose A1C is 7%, compared to those with higher A1C levels. Paradoxically, there is an increase in heart attacks in people with type 2 diabetes who have had the disease for a long time (10 to 15 years) and if their A1C target is reached with a lot of accompanying low blood sugars. One thing we have learned from recent studies is that the heart doesn’t like the stress of low blood sugar levels caused by medications such as insulin.
Other studies have shown that how A1C is lowered in type 2 diabetes may make a difference, in terms of which diabetes medications are used. In studies where people with diabetes had already had an event or had many risk factors, two classes of medications were shown to reduce the recurrence of a vascular event: SGLT2inhibitors (the “pee sugar” drugs) and GLP1 agonists such as liraglutide (Victoza®).
B: Blood pressure
The risk of a vascular event is much higher if the person with diabetes also has uncontrolled high blood pressure. Ideal blood pressure for someone with diabetes is 130/80 mm Hg. A reduction of 10 mmHg systolic or 5 mmHg diastolic will reduce coronary disease by 22% and stroke by 41%. There are excellent medications to treat high blood pressure, and it is very important that people with high blood pressure continue to take their medication and see their diabetes team regularly.
I often hear people with diabetes say, “I’m told that my cholesterol is fine.” The reality is that anyone with type 2 diabetes who is over 40 years old will reduce their lifetime risk of having a heart attack if they take a statin medication to lower their cholesterol level, even if it is not particularly high. There is a benefit to taking the statin earlier (i.e. less than 40 years of age) if the person with diabetes shows any signs of having heart or blood vessel damage, such as diabetic eye disease or protein in the urine. (For more information about diabetes complications, click here.
D: Drugs that protect the heart
As mentioned above, drugs that lower cholesterol also reduce the risk of heart attack. Another type of medication is one that lowers blood pressure but is used in people with type 2 diabetes who are over the age of 55 and have a risk factor for a vascular event, even if they don’t have high blood pressure. The reason is that lowering the pressure in the kidney also seems to be good for the heart. For this medication class – called “ACE inhibitors” and “ARBs” – take a test to see if you should be on them.
Drugs that reduce the way platelets stick together in the blood vessels can reduce vascular events. The evidence, however, for ASA in people whose only risk is diabetes, has not shown to be of benefit. If you have had a vascular event, then ASA or other antiplatelet therapy is recommended.
E: Exercise and eating right
Risk factors such as obesity or having a sedentary lifestyle also lead to a higher risk for having a heart attack. That’s why regular exercise is important, as well as eating a healthy diet. There is also evidence that certain diets can also help reduce the risk of a vascular event.
S: Stop smoking
Probably the changeable risk factor that will make the biggest difference in protecting you against a heart attack is to stop smoking. Diabetes is a disease that involves the blood vessels, and smoke is directly harmful to them.
S: Screening for complications
One of the main goals of treating diabetes is to prevent complications. As well, it is important to look for complications so that if they are present, their rate of progression can be slowed. Moreover, since the complications of diabetes are blood vessel related, discovering one complication (e.g. kidney disease) increases the risk for other complications (e.g. heart attack), and preventive treatment can be more aggressive.
People with diabetes may have cardiovascular events and be unaware. So screening for heart disease with an ECG, which measures the electrical activity of the heart, is recommended every 3 to 5 years for:
- People over the age of 40
- People with diabetes for more than 15 years (and are over the age of 30)
- Those with any complications from diabetes already (such as damage to the eyes, kidneys, nerves, or if there is erectile dysfunction)
- People less than 40 years old, who have risk factors such as smoking, high blood pressure or a strong family history
In addition, people with diabetes should be assessed for eye damage with an exam by an eye specialist. Kidney damage with a urine test (ACR) and blood test (eGFR) should be assessed yearly, or more often if chronic kidney disease is present. Finally, nerve damage should be assessed with a monofilament test to the feet yearly, or more often if nerve damage is present. Click here for a useful link to help you keep track of tests.
S: Self-management, stress and other barriers
This is probably the most important letter of the ABCDES. If you are not achieving your goals for your diabetes management, let your healthcare team know about any barriers you have. These could be financial issues (a common reason why people don’t take their diabetes medications or stop checking blood sugars.) It could also be stress-related. Living with diabetes day in and day out can cause burnout and sharing this with your team may help you achieve your goals. People living with diabetes have a higher rate of depression, which can decrease your ability to manage your diabetes. Setting goals will improve your diabetes management. Ask for your team for help to make these goals SMART (Specific, Measurable, Achievable, Realistic, Timely).
Even though having diabetes is a risk factor for having a heart attack, there are lots of things you can do to lower your risk.