Evidence that treatment can reduce or eliminate the risk of cardiovascular disease and death in type 2 diabetes
Another world first for people with diabetes was published and this time it concerns type 2 diabetes. Researchers from the University of Gothenburg and the National Diabetes Register have just published a study that affects everyone with type 2 diabetes. The study, published in the most reputable medical journal the New England Journal of Medicine, brings a lot of positive to everyone who has type 2 diabetes. The main result of the study is that people with type 2 diabetes do not need to have higher mortality and higher risk of cardiovascular disease, compared to people without type 2 diabetes. The founders behind diabeteson.com are part of the research group behind the study. Below we explain the study in detail so that you who have type 2 diabetes can understand and assimilate this knowledge.
Why was the study done and what questions does it answer?
The purpose of the study is to answer the following questions:
- Can I reduce or even eliminate my elevated risk of cardiovascular disease and death by controlling my risk factors (high blood pressure, high blood lipids, high blood sugar, etc.)?
- What risk factors are most important for preventing cardiovascular disease and premature death?
- Do I have any additional gain from treating my blood pressure, blood sugar and blood lipids to even lower levels than recommended?
- Does it matter when in life I develop type 2 diabetes?
Why are these questions important to you?
The goal of diabetes care is that if you have type 2 diabetes, you should live a normal life, without barriers and without increased risk of cardiovascular disease, cancer or death. You should be able to live a normal life without worries. Unfortunately, the reality is such that diabetes entails an increased risk of cardiovascular disease and premature death. This has been known for over 50 years. In most previous studies, people with type 2 diabetes have between 2 and 6 times increased risk of cardiovascular disease and death, compared to people without type 2 diabetes. In order to prevent this risk, we have been better at treating risk factors such as high blood pressure and high blood lipids in recent decades. Over the years, numerous studies have shown that it is favorable to treat these risk factors. The risk of a heart attack is reduced by receiving treatment with drugs that lower blood fats, as well as by treating high blood pressure with drugs that lower blood pressure.
Target values for risk factors
Diabetic care is working for you to achieve what we call target values. For example, the target value for HbA1c is 52 mmol/mol, which means that you should preferably have less than 52 mmol/mol. For blood lipids (LDL cholesterol), the target value is 2.5 mmol/L.
The two big questions
Question 1: How good can it be if I achieve all the target values? In fact, this has never been investigated and therefore we do not know whether people with type 2 diabetes can get rid of the risk associated with diabetes.
Question 2: Which of all these risk factors is most important? We currently do not know which ones are the most important and therefore we do not know where the focus should be either.
This study is the first to answer these important questions and for those who have diabetes, the study brings a very positive message.
Facts about the study
- The study included about 270,000 people with type 2 diabetes. Each person with diabetes was compared with 5 people without diabetes (from the general population).
- For people with diabetes, the following risk factors were assessed:
- Long-term blood sugar (HbA1c)
- Blood pressure
- Presence of kidney damage (albuminuria)
- High blood lipids
- For each risk factor you had (i.e. if you did not reach the target value), you got 1 point. Thus, people with type 2 diabetes could have 0 to 5 points: 0 points mean that all risk factors were controlled and 5 points meant that no risk factor was controlled.
- The risk of death and cardiovascular disease was investigated in relation to the number of risk factors. Thus, the comparison was made against people without diabetes (from the general population)
What did the study show?
The main result of the study is very pleasing and for those who have type 2 diabetes. The main results are as follows:
The risk of death
People with type 2 diabetes who managed to control all the risk factors hardly had an increased risk of death. This means that the risk of death was reduced so sharply that people with diabetes had basically the same mortality rate as people without diabetes (if all the risk factors were managed to control). This is sensational results and means that you who have diabetes have a huge amount to gain from seeking good risk factor control. Below is a diagram showing the risk of death in relation to how well controlled the risk factors were (note that the results are also shown in relation to age). The diagram below also shows that the risks were lower the older one.
Risk of a heart attack
If you managed to control all the risk factors, you had no increased risk of a heart attack. The fact is that people with diabetes even had a lower risk of a heart attack than people without diabetes (if you checked all risk factors). This is also sensational news!
The risk of stroke was very similar to the risk of a heart attack.
Risk of heart failure
Unfortunately, people with diabetes could not eliminate their risk of heart failure, even if they controlled all the risk factors (the only exception was the very oldest people). This means that heart failure remains a challenge for diabetes care.
How did those who did not manage their risk factors?
Those with diabetes who could not achieve the target of the risk factors had an increased risk of heart attack, stroke, and heart failure, and fivefold increased risk of premature death compared to controls. What is crucial is how well people with type 2 diabetes control a number of risk factors using medicines and by being smoke-free.
What risk factors are most important?
This is a fundamental issue because you who have diabetes have a big challenge ahead of you and it is important to know where you and your caregiver should focus. The study shows that low physical activity, high blood lipids, high blood sugar, high blood pressure and impaired renal function (albuminuria) are the absolute strongest risk factors for cardiovascular disease and death. That is, it is these risk factors that are most important to treat.
Smoking and low physical activity appear to be the strongest risk factors for premature death, while elevated blood sugar, elevated blood lipids, high blood pressure (hypertension) and low physical activity are the strongest risk factors for acute myocardial infarction and stroke.
The main risk factors for heart failure were atrial fibrillation, high body mass index (BMI), high blood sugar and impaired renal function. People with type 2 diabetes should focus primarily on these risk factors in order to influence the risk of cardiovascular disease and death.
The following figures show (in descending order) which risk factors were most important for death and heart attack.
What levels are optimal for blood pressure, blood sugar and blood lipids?
The study also examined whether it made sense to try to reach even lower levels of HbA1c, LDL cholesterol and blood pressure. Currently, there are target values that you are trying to achieve and you usually “settle” if you reach these target values. The purpose of this investigation is therefore to clarify whether there was any further profit from coming even below the target value. The results showed that even lower blood pressure, even lower blood sugar and even lower blood lipids were associated with lower risk of heart attack and complications.
How difficult is it really to achieve all the target values?
The fact is that the risk factors examined can be achieved by the vast majority with type 2 diabetes. There are very effective drugs to treat blood pressure, blood lipids and blood sugar. However, it is more difficult to deal with kidney damage and smoking, but even there are treatments and measures that are effective. Recall that we did not investigate how “good” it can be if you also eat the right diet and exercise. People with diabetes are highly likely to reduce their risks further if the two risk factors (diet and exercise) can also be addressed.
Meaning of age
The study also showed that the risk of complications, especially of heart failure, is greatest among those who are younger. Therefore, it is especially important to control and treat risk factors if you are younger. In other words, the younger you are, the higher the risks and therefore it is even more important to be aggressive with the treatment.
What is missing in the study? Diet.
The study has not investigated the importance of the diet. There is no doubt that the diet is extremely important for those who have type 2 diabetes and therefore it is a pity that the diet was not examined in this study (dietary data are not available in the National Diabetes Register). However, it is highly likely that the person who also manages the diet correctly has even lower risks than the one shown above. We can therefore recommend that you who have type 2 diabetes should make an effort to restructure your diet and be physically active on a regular basis.
There is now strong evidence that people with diabetes do not have to live a life filled with worries about cardiovascular disease and complications. This study is a milestone that shows that risk factor control can do a huge amount for those who have diabetes. If you manage to achieve target values for the five risk factors studied here, you can significantly reduce, or even eliminate, the risk of cardiovascular disease and death. You have to work hard, together with your caregiver, to maintain physical activity, control blood pressure, blood lipids, blood sugar and prevent kidney damage.
Rawshani A, Rawshani A, Franzén S, et al. Risk Factors, Mortality, and Cardiovascular Outcomes in Patients with Type 2 Diabetes. N Engl J Med. 2018;379(7):633-644.