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Researchers investigate shisha cancer risk

Dr. Ravinder Mamtani and Dr. Sohaila Cheema.
Dr. Ravinder Mamtani and Dr. Sohaila Cheema.

Researchers at WCM-Q have conducted a comprehensive study to determine the cancer risk posed by smoking from a water-pipe.

While the risks of smoking cigarettes are well known, the cancer risk associated with smoking from a water-pipe - also known as shisha, hookah and ‘hubble bubble’ - remain poorly understood.

A team of researchers led by WCM-Q’s Dr. Ravinder Mamtani and Dr. Sohaila Cheema, used a sophisticated meta-analysis technique to review 28 published scientific studies and examined the relationship between water-pipe smoking and various forms of cancer, including cancer of the head and neck, esophagus, stomach, lung and bladder.

Dr. Mamtani, associate dean for global and public health at WCM-Q, said the need for such a study had become urgent in recent years owing to the surge in popularity of shisha, especially among young people and women. He said:

“There are many studies examining the risks of cigarette smoking but we must understand that smoking from a water-pipe is significantly different because the smoker generally inhales far more smoke, smokes for longer, and there are different concentrations of toxins in water-pipe smoke than in cigarette smoke.

Furthermore, there is a very dangerous and frankly wrong perception that water-pipe smoking is safe because the water somehow filters out the dangerous toxins in the smoke. I cannot emphasize enough that this is not true. The water only cools the smoke, it does not filter out the toxins.”

Dr. Cheema, director of global and public health at WCM-Q, said:

“Water-pipe smoking is a very social act and in the Middle East it is more socially acceptable for women than smoking cigarettes. This means that patterns of use are quite different from cigarette smoking so it is vital that we study water-pipe use separately to understand the risks more clearly.”

Data from a 2014 World Health Organization (WHO) study shows that tobacco kills up to half its users, amounting to nearly six million people each year. More than 600,000 deaths per year are the result of non-smokers being exposed to second-hand smoke. The Qatar World Health Organization Step Survey of 2012 found that 29.1 per cent of men in Qatar smoke, and 0.6 per cent of women.

Unpublished WCM-Q data indicates that among adolescents in Qatar aged 15-18 years, 13 per cent reported they had tried cigarettes and 22 per cent that they had tried water-pipe. Among college students in Qatar, 27 per cent said they were regular or social cigarette smokers, and 32 per cent regular or social water-pipe smokers.

A water-pipe smoking session can expose the user to up to 50 liters of smoke over a 45-minute use period, compared to around one liter of smoke that is consumed by someone smoking a cigarette over about five minutes. Water-pipe smokers are exposed to tar, addictive nicotine, carbon monoxide, and other harmful substances at similar levels and sometimes greater levels than cigarette smokers.

The meta-analysis of the 28 studies revealed data that points to a strong association between water-pipe smoking with cancers of the head and neck, esophagus and lung. The study, entitled ‘Cancer risk in water-pipe smokers: a meta-analysis’ has now been published in the International Journal of Public Health.

Other contributing authors to the study are Dr. Javaid Sheikh, dean of WCM-Q, Dr. Ahmad Al Mulla of the Smoking Cessation Program at Hamad Medical Corporation (HMC), Dr. Albert Lowenfels of the Department of Surgery at New York Medical College, and Dr. Patrick Maisonneauve of the Division of Epidemiology and Biostatistics and the European Institute of Oncology.

Dr. Cheema added:

“Our analysis of the existing studies points to a clear association between water-pipe smoking and several forms of cancer and people need to be aware of this so that they can make informed choices about whether they smoke or not. We also determined that the number of high-quality studies into the effects of water-pipe smoking is very low, so there is a great need for more investigation in this area, especially as shisha is so popular nowadays.”

Dr. Mamtani said:

“Governments around the world have taken steps to reduce cigarette smoking in their populations through measures such as public health campaigns, tax policy, creating smoke-free areas and passing laws about what can be displayed on packaging. Until now, water-pipe smoking has managed to escape many of these measures.

It is time for more studies about water-pipe smoking, more public awareness of the risks and we can also explore the opportunities for public policy on this issue to protect public health.”

The full research paper can be read at: