Dec 13 2011 --- Chewing the natural stimulant khat increases the risk of death and stroke in patients with heart disease compared to those who are not users, according to new research in Circulation: Journal of the American Heart Association.

Since ancient times, people in the Arabian Peninsula and East Africa have chewed the fresh leaves of the Catha edulis plant which has effects similar to amphetamines and cocaine. It causes euphoria, hyperactivity, restlessness, loss of appetite and weight loss.

In Yemen, some people have khat picnics, chewing the leaves for as much as three hours, like tobacco chewing. Its use has spread globally throughout Western Europe and into the United States. Seven metric tons of khat travel through Heathrow Airport in England each week, and fresh and dried khat has been seized and confiscated in the United States where it is illegal, researchers said.

In the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2) Study, researchers comparing 1,408 khat chewers to 5,991 people who didn't use khat found:

In the hospital, khat users had a 7.5 percent death rate from heart disease compared to 3.8 percent in those who were not khat users.
At one month, the death rate was 15.5 percent among khat users and 6.4 percent for non-khat users.
At one year, the death rate was 18.8 percent among khat users compared to 10.8 percent among non-users.

For the study, researchers enrolled men and women from 65 hospitals in Saudi Arabia, Bahrain, Yemen, Qatar, United Arab Emirates and Oman.

About 96 percent of the khat users were from Yemen, where khat is legal and socially acceptable, unlike the other countries in the study.

"Global awareness of the negative impact of khat chewing on health and social life is warranted before it becomes endemic," said Jassim Al Suwaidi, M.B., Ch.B., study co-author and Consultant Cardiologist and Director of Cardiovascular Research in the Department of Cardiology and Cardiovascular Surgery at Hamad General Hospital in Doha, Qatar. "This report underscores the importance of improving education about the cardiovascular risks of khat chewing as well as the need for further studies in the field."

Furthermore, researchers found:

Khat chewers were more likely to be men (only 14 percent were women) and had lower cardiovascular risk factors such as diabetes mellitus, hypertension and dyslipidemia.
Death rates were consistently higher among khat users up to age 80, but khat chewing occurs across the spectrum of young and old, male and female.
Users were more likely to experience adverse health effects, including heart failure, recurrent ischemia, a second heart attack, cardiogenic shock and stroke compared to non-users.
Women were as likely as men to experience adverse heart effects.
Male khat chewers were more likely to develop stroke, particularly hemorrhagic (bleeding) stroke, compared to non-users. The increased risk of stroke wasn't significant among women using khat.

The worse in-hospital outcomes may be related to delays in people getting to the hospital after the onset of symptoms and failing to receive thrombolytic (clot-busting) therapy or treatment with beta blockers, researchers said.