Simultaneously with many Danish type 2 diabetic patients receiving preventative treatment for heart disease, their risk of blood clots in the heart and heart failure has fallen so significantly that it is today only marginally above that of the population as a whole.

"Today, type 2 diabetes is a less serious disease, and this is because in Denmark we’re better at treating patients in a preventative manner," says Michael Mæng, who is a consultant at Aarhus University Hospital and associate professor at Aarhus University.

This is shown by a new study from Aarhus University Hospital and Aarhus University, in which researchers have examined the extent of heart disease and heart failure in 209,311 newly diagnosed patients with type 2 diabetes who had not previously had heart disease, and then correlated the results with a control group of almost one million people without diabetes. All of them were followed over a seven year period.

The risk has fallen and so have the differences

By comparing the periods 1996-1999 and 2008-2011, the researchers found large decreases in the risk of thrombosis and death for the group with type 2 diabetes. Between 1996-1999 and 2008-2011, the risk of a blood clot in the heart was more than halved (falling from 6.8 per cent to 2.8 per cent) and the mortality risk fell from 29 per cent to 17 per cent during the study.

In comparison with the control group, the difference in risk narrowed during the course of the study. At the end of the study, the risk of a blood clot in the heart among patients with type 2 diabetes was only marginally higher – at 0.6 percentage points higher – than in the control group.

In another study, the research group calculated the risk of a blood clot in the brain for the same groups, and here the picture was the same. The risk for persons with type 2 diabetes fell by half, and the difference in risk compared to the control group also narrowed significantly.

During the same period, the proportion of Danes with type 2 diabetes who take preventive medicine for heart problems has increased. This is particularly true of cholesterol lowering medicine (statins), which have risen from five per cent in 1996-99 to 60 per cent in 2008-11, although the use of aspirin and blood pressure lowering drugs has also increased.

Result of new guidelines

In 2003, a Danish treatment study (the Steno 2 study) showed that the risk of heart disease in patients with type 2 diabetes could be reduced through targeted, long-term and intensive efforts against risk factors such as high blood pressure, cholesterol and blood sugar levels.

"Following the publication of the results of the Steno 2 study, we introduced new guidelines in Denmark which have meant that we’re more aware of the need to examine people for type 2 diabetes and to offer patients preventative treatment for cholesterol levels and blood pressure," says Michael Mæng.

"What's new in our study is that we’ve now shown the rest of the world that here in Denmark, we’ve made this work in practice. So earlier detection of diabetes and far better preventative treatment has had a significant effect in Denmark. But we can also see that there's still more to be done. Only half of the people with type 2 diabetes were receiving statins at the end of the study period. Everyone with type 2 diabetes ought to be receiving them, at least until we know more about who will benefit most from them.”

Since the end of the study, some new medications have been added in the form of the so-called GLP1 agonists and SGLT2 inhibitors, which appear to protect diabetic patients from e.g. blood clots in the heart and brain as well as heart failure.

"Our expectation is that the new medications will be able to further reduce the difference in the risk of blood clots and heart failure between people with type 2 diabetes and those who don’t have the disease," says Michael among G.

The research results – more information:

Type of study: Register-based study

Partners: The departments of Clinical Epidemiology and Cardiology, Aarhus University Hospital

External funding: Financed by the Department of Cardiology at Aarhus University Hospital. The study has not received any external funding.

Conflicts of interest: Kevin K.W. Olesen has received remuneration from Bayer for projects that are not related to the current study. Michael Mæng has received remuneration for advice, meetings and lectures from AstraZeneca, Bayer, Boehringer-Ingelheim, Boston Scientific, Bristol-Myers Squibb and Novo Nordisk in connection with projects that are not related to the current study.

The Department of Clinical Epidemiology receives funding for other studies from companies in the form of research grants made to (and administered by) Aarhus University. None of these studies have anything to do with the current study.

Read the scientific article:

Nationwide Trends in Cardiac Risk and Mortality in Patients With Incident Type 2 Diabetes: A Danish Cohort Study. Christine Gyldenkerne, Jakob S. Knudsen, Kevin K.W. Olesen, Henrik T. Sørensen, Hans E. Bøtker, Reimar W. Thomsen, Michael Mæng. Diabetes Care Aug 2021, dc210383; DOI: 10.2337/dc21-0383

Further information:

Michael Mæng
Consultant at the Department of Cardiology at Aarhus University Hospital
Associate Professor at the Department of Clinical Medicine at Aarhus University
Tel.: (+45) 2670 3237                       
Email: michael.maeng@ki.au.dk