“Broken heart syndrome” may harm more than just the heart, new research suggests.

While the extreme stress of losing a loved one has been linked to heart troubles in prior research, a new study found that one in six people with broken heart syndrome also had cancer. Even worse, they were less likely to survive their cancer five years after diagnosis.

“There seems to be a strong interplay between Takotsubo syndrome [broken heart syndrome] and malignancies,” said study senior author Dr. Christian Templin. He’s director of acute cardiac care at University Hospital Zurich in Switzerland.

“Therefore, it should be recommended for Takotsubo syndrome patients to participate in cancer screening to improve overall survival,” he said, adding that the reverse is also true. Still, the study did not prove that one causes the other.

Broken heart syndrome causes sudden intense chest pain and shortness of breath that can be mistaken for a heart attack. These symptoms are a reaction to a sudden surge in stress hormones, according to the American Heart Association (AHA).

The condition causes the heart’s main pumping chamber to enlarge, the researchers said. And that means the heart can’t pump blood effectively.

Broken heart syndrome can happen after just about any intensely emotional experience. The death of a loved one, a breakup or divorce, financial problems and even an intensely positive experience like winning the lottery can trigger broken heart syndrome, the AHA said.

Major physical stress can also trigger broken heart syndrome. A physical trauma or surgery, respiratory failure and infections are examples of physical stresses that can contribute to broken heart syndrome, the study noted.

The new study included just over 1,600 people with broken heart syndrome. The participants were recruited at 26 medical centers in nine different countries, including eight European countries and the United States.

Among those diagnosed with cancer, most were women (88%) and their average age was 70.

The incidence of cancer cases was much higher than would normally be expected, Templin said. That was true for both genders and all age groups. For example, in women aged 44 years and younger, the expected rate of cancer is 0.4%, but for those with broken heart syndrome it was 8%. In men 45 to 64 years old, the expected rate of cancer was 2%, but in those with broken heart syndrome, it was 22%. In both older men and women, the expected cancer cases were more than double what would be expected for those with broken heart syndrome.

The most common type of cancer was breast cancer. Other cancers affected areas including the digestive system, the respiratory tract, internal sex organs and the skin.

People who also had cancer were more likely to have a physical trigger for broken heart syndrome than an emotional one, the findings showed.

Templin said it’s not clear from this study exactly how these conditions are linked, though he noted that stress from a cancer diagnosis might trigger broken heart syndrome. It’s also possible that metabolic or hormonal changes caused by cancer could increase the risk of broken heart syndrome.

Dr. Guy Mintz, director of cardiovascular health and lipidology at Northwell Health’s Sandra Atlas Bass Heart Hospital in Manhasset, N.Y., said, “Many cancer patients have both significant emotional stress and multiple medical interventions, the most common triggers found in this study.”

But he noted that “the study was too small and the cancers too variable to draw conclusions regarding a direct mechanism and the interaction of the two diagnoses on longevity.”

Mintz said it’s important for physicians to be aware of the link between broken heart syndrome and cancer so that doctors — including primary care, cancer and heart doctors — can intervene earlier in the course of either condition.

The findings were published online July 17 in the Journal of the American Heart Association.

More information

Learn more about broken heart syndrome from the American Heart Association.