- A nationwide Danish study found that sudden cardiac death was 3.7 times more common in people with type 1 diabetes and 6.5 times more common in people with type 2 diabetes than in the general population.
- The relative risk was greatest in younger adults: people under 50 with diabetes had about seven times the risk of sudden cardiac death compared with their peers without diabetes.
- Sudden cardiac death accounted for a sizeable slice of reduced life expectancy in diabetes, although newer treatments such as SGLT 2 inhibitors and GLP 1 drugs were not yet in widespread use during the study period.
Researchers used national registers to analyse all 54,028 deaths in Denmark during 2010.
They reviewed death certificates, hospital records and autopsy reports to identify cases of sudden cardiac death, where people died unexpectedly from a presumed heart cause.
They then linked this information to data on diagnosed type 1 and type 2 diabetes and compared rates of sudden cardiac death between those with and without diabetes.
Because the study used whole population data, it avoided some of the selection problems that affect smaller cohorts.
What the researchers found
Out of all deaths, 6,862 were classified as sudden cardiac death. When the team compared groups, they found a clear pattern.
Sudden cardiac death was far more frequent in people with diabetes than in those without. Compared with the general population, rates were 3.7 times higher in type 1 diabetes and 6.5 times higher in type 2 diabetes.
The relative difference was most striking in younger adults.
People under 50 with diabetes had around seven times the risk of sudden cardiac death compared with people of the same age without diabetes.
The study also looked at life expectancy.
On average, people with type 1 diabetes lived 14.2 years less and those with type 2 diabetes 7.9 years less than those without diabetes.
Sudden cardiac death explained 3.4 of the years lost in type 1 and 2.7 of the years lost in type 2 diabetes.
The authors stress that this is observational research. It shows a strong link between diabetes and sudden cardiac death but cannot prove that diabetes itself directly causes the deaths.
Factors such as ischaemic heart disease, hypoglycaemia and cardiac autonomic neuropathy are likely to contribute.
What this means for people living with diabetes
These findings reinforce what many guidelines already say.
For people with diabetes, protecting the heart is not optional, it is central to care.
That means:
- managing blood pressure, lipids and glucose
- not smoking
- getting regular reviews of kidney function and heart symptoms
- asking whether heart protective medicines such as SGLT 2 inhibitors or GLP 1 drugs are appropriate in your case
The authors note that their data come from 2010, before many of the modern therapies and devices in routine use today.
Risk today may not be identical. Even so, sudden cardiac death clearly contributes to reduced life expectancy in diabetes, particularly in younger adults, and deserves attention from patients, clinicians and policy makers.
