An international study, published Thursday in the European Heart Journal, has found that patients with a history of high blood pressure are at greater risk of dying from coronavirus.

Researchers found that COVID-19 patients with high blood pressure, or hypertension, have twice the risk of dying from the disease.

It is well known that high blood pressure worsens the risk of serious coronavirus symptoms, and the study shows how bad the risk is.

Lead researchers Fei Li and Ling Tao of the department of cardiology at Xijing Hospital in Xian, China, examined the data of more than 2,860 patients who were treated in Wuhan, where the epidemic was first noticed. They found that nearly 30 percent of them had high blood pressure.

Tao said, “Soon after we started to treat COVID-19 patients in early February in Wuhan, we noticed that nearly half of the patients who died had high blood pressure, which was a much higher percentage compared to those with only mild COVID-19 symptoms.”

The researchers noticed that 4 percent of patients with hypertension died, compared to 1 percent of those with normal blood pressure. Later, they found that the risk of dying doubled among hypertensive patients.

The team also found that more than 7 percent of patients who had stopped taking their antihypertensive drugs died of coronavirus.

The researchers then examined the medical records of 2,300 more patients to understand whether it mattered which antihypertensive drugs they took.

There have been concerns over the blood pressure drugs, such as Angiotensin-converting enzyme (ACE) inhibitors and Angiotensin II receptor blockers (ARBs), which were believed to help the virus to enter the cells. Some experts expressed concerns over those drugs, stating that they could make it easier for the virus to invade human cells. However, the team did not find evidence of that.

Tao explained, “We were quite surprised that these results did not support our initial hypothesis; in fact, the results were in the opposite direction, with a trend in favor of ACE inhibitors and ARBs. Therefore, we suggest that patients should not discontinue or change their usual antihypertensive treatment unless instructed by a physician.”

“It is important that patients with high blood pressure realize that they are at increased risk of dying from COVID-19,” Li said. “They should take good care of themselves during this pandemic and they need more attention if they are infected with the coronavirus,” Li added.