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Advancing Science for Global Health
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Home > Global Health Matters Mar/Apr 2011 > Researching the roots of khat addiction in Yemen Print

Researching the roots of khat addiction in Yemen

March/ April 2011 | Volume 10, Issue 2

In Yemen, khat is the national plant and daily habit. Unfortunately, its consequences are extremely negative. Chewing the leaves of the evergreen shrub releases an amphetamine-like stimulant. Though it’s considered highly addictive, there is virtually no research on how it affects brain function.

Dr. Mustafa al’Absi, a professor of psychology at the University of Minnesota-Duluth, began studying the neurobehavioral effects of khat use in his native country with support from Fogarty. The drug is undermining national productivity and contributing to the country’s water shortage; a daily bag of chew requires an estimated 500 liters of water to produce. A high unemployment rate among youth is part of the shaky economy and political instability is aggravated by terrorist elements.

Two men sit in front of wooden hut, one with droopy eyes stuffs handful of khat into his mouth, the other looks off the camera
Photo by Curt Carnemark/World Bank

Many Yemenis chew khat as a daily habit, but the
drug is linked to decreased productivity, increased
traffic fatalities and even a national water shortage.

Against this backdrop, al’Absi is hopes his findings help curb the use of the drug and inform public policy decisions by linking chewing khat with cognitive and emotional malfunctions. Khat seems to affect stress response and is linked to an increase in road accident fatalities.

At universities in Sanaa and Taiz, al’Absi has begun studying khat users and hopes to ultimately recruit 150 participants. After filling out questionnaires regarding their health and khat use, subjects are then given some psychological challenges and other tasks that are mentally demanding. “We’re trying to see how reactivity to these challenges varies as a function of chronic khat use, or tobacco use and a combination of those and compare that with the controls,” said Al’Absi.

On a subsequent visit, subjects perform various cognitive tasks to measure attention, memory and concentration. Based on early results, al’Absi said he has “a hunch that people using stimulants will have difficulties with challenges and coping with acute stressors... one of the things that interests me is how people regulate their emotions. How people cope with stress or emotionally charged situations may be impacted by stimulants like khat.”

Three boys and two men sit and stand around a large pile of khat branches and leaves on the ground, large blue metal door behind
by Curt Carnemark/World Bank

Chewing khat seems to affect stress
response and the ability to perform
cognitive tasks, early results of the
study show.

As with other addictive substances, there is a supposition that khat use leads to “a high prevalence of certain psychopathology,” said al’Absi. Based on snapshot data and some anecdotal experience, “there seems to be a lowering of the threshold for having full blown episodes of depression and psychotic behavior,” he explained.

The subject matter is important to the mental state, economic productivity, stability and ultimately the future of the Yemeni people. There are also ramifications for thousands of U.S. immigrants from Africa and the Middle East who have brought the habit with them and now find khat easy to obtain in New York, Los Angeles, Detroit, Dallas and other cities.

Al’Absi said the khat project actually began with a Fogarty International Research Collaboration Award (FIRCA) that sparked the conversation between researchers in Minnesota and Yemen. This behavioral study, he said, helped the evolution of proposals focusing on both social-behavioral studies and infectious disease studies. Al’Absi was able to leverage the FIRCA into a larger grant from the National Institute on Drug Abuse (NIDA), which demonstrated Fogarty’s ability to nurture budding global heath researchers.

Apart from training a Yemeni cadre in addiction research, al’Absi helped establish the nation’s first Institutional Review Board and conducted training in ethical issues. His team forms a network of U.S., European and Yemeni scientists and al’Absi hopes this will foster Yemeni-American scientific cooperation and capacity-building efforts.

“You know, khat is endemic in countries that are already highly burdened and taxed by many social, economic and other burdens, and it really takes some good insight and leadership to champion some of those marginal, but highly impactful problems,” said al’Absi. “So I hope Fogarty and NIDA continue to champion these issues.”

In addition to building research capacity in Yemen and perhaps even leading to growth in the biomedical field, the studies could provide some insight as Americans struggle to fight a still widespread addiction to tobacco products.

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