• Posted May 8, 2025

Down Syndrome Patients Have Higher Stroke, Heart Attack Risk

People with Down syndrome have a much higher risk of stroke than people without the genetic disorder, a new study says.

Down syndrome patients have a 5.14 times higher risk of a stroke caused by a brain bleed, and more than 4 times higher risk of a stroke caused by a blood clot, researchers reported May 7 in the Journal of Internal Medicine.

Younger patients with Down also have an increased risk of heart attack, researchers found.

“Our results show that individuals with Down syndrome are at increased risk of some age-related cardiovascular outcomes, and indicate, in line with results from previous studies, that their cardiovascular risk factor profile differs from the general population,” lead researcher Annie Pedersen of the University of Gothenburg in Sweden said in a news release.

In Down syndrome, patients have an extra copy of chromosome 21, which changes how their body and brain develops, according to the U.S. Centers for Disease Control and Prevention (CDC).

During recent decades the life expectancy for people with Down syndrome has increased dramatically, rising from an average 25 years in the early 1980s to 60 years in 2020, researchers said in background notes.

With age comes increased risk of heart-related health problems, however. Researchers wondered whether the genetic differences of Down syndrome might mean different risks for these patients as they grow older.

For the study, researchers tracked nearly 5,200 people with Down syndrome born in Sweden between 1946 and 2000, and compared their stroke and heart attack risk to the country's general population.

Results showing higher risk for stroke “could have future implications for the surveillance and treatment of individuals with Down syndrome,” Pedersen said.

The increased risk of blood-clot-related stroke is likely due to the presence of congenital heart disease or diabetes, rather than the result of clogged arteries, researchers said.

Likewise, it’s possible that brain-bleed strokes among Down syndrome patients might be driven by obesity, high cholesterol, lack of exercise and other unhealthy lifestyle factors, researchers said.

More information

The U.S. Centers for Disease Control and Prevention has more on Down syndrome.

SOURCES: Wiley, news release, May 7, 2025; Journal of Internal Medicine, May 7, 2025