As a child growing up in Alexandria, Egypt, Mary Rezk-Hanna would stand on her family’s apartment balcony and watch men smoke below at the hookah café. The smell of the flavored tobacco was pleasant and as she watched the centuries-old ritual, a curiosity was sparked that would eventually lead to her current research on the human health effects of hookah.
Dr. Rezk-Hanna is an Assistant Professor at UCLA’s School of Nursing and has been funded by the Tobacco-Related Disease Research Program (TRDRP) to study the human blood vessel (vascular) health effects of hookah. Traditional hookah water pipes burn charcoal briquettes to heat and combust flavored tobacco, the smoke passes through a water reservoir and users inhale the vapor through a long hose. Recently, electronic hookah products have been introduced that use heated coils to aerosolize flavored liquids containing nicotine. E-hookah pens resemble e-cigarettes, while e-hookah bowls attach to traditional water pipes where users inhale the vapor through a hose. Dr. Rezk-Hanna’s research spans the use of both devices among young, healthy adults.
When asked how she became interested in science, Dr. Rezk-Hanna replied, “my father is a surgeon, specializing in urology, and growing up, our family moved with him to several parts of the Middle East over the course of his career. He would bring my brother and me with him on clinical rounds and quiz us on the proper diagnosis and treatment of his patients.” Reflecting on her father’s character, she added, “he was courageous, innovative and compassionate; I strive to live up to his example.”
After moving to Virginia in 2000, where she attended George Mason University as an undergraduate, she noticed that hookah users in the States were more diverse than those of her childhood. While mainly older men used hookah in Egypt, she saw healthy young men and women using hookah in the States. When she began her graduate research at UCLA, with the late Ron Victor, she was surprised to learn that this centuries-old tobacco product was greatly understudied.
Dr. Rezk-Hanna received a TRDRP dissertation award in 2014 to begin her study of the human health effects of hookah. Her research results demonstrate that smoking hookah injures blood vessels in ways that are equivalent to those reported after smoking combustible cigarettes. This is significant given the misperception among hookah users that smoking hookah is safer than smoking combustible cigarettes.
In a scientific statement from the American Heart Association authored by leading cardiovascular researchers, including Dr. Rezk-Hanna, authors noted that “A majority of users believe that hookah tobacco smoking is less harmful than cigarette smoking, that the probability of addiction is low, and that quitting hookah tobacco smoking is not difficult.” Dr. Rezk-Hanna’s research challenges that belief and provides objective scientific evidence that hookah is also harmful to the human vasculature.
Using preliminary data generated while funded by TRDRP as a graduate student, Dr. Rezk-Hanna has gone on, in her own laboratory, to successfully compete for funding from the National Institutes of Health as well as TRDRP, to continue her research on the health effects of hookah. Her work evaluates differences in health effects of traditional charcoal-heated hookah and e-hookah and dissects the effects of flavorings and nicotine on the vasculature when delivered through e-hookah. It is critical to understand the relative contributions of e-liquid ingredients given the diversity of liquids in use. Understanding each component will help provide more specific data to understand the health effects of vaping, now made more critical by the outbreak of vaping-associated pulmonary injury, and the epidemic of youth vaping.
“The research tells us that [vapes] have become the most popular tobacco products for youth and are attracting people to nicotine,” says Dr. Rezk-Hanna, “While [vapes] have helped some smokers to stop using combustible tobacco, the long term health effects are not well-understood. There’s an urgent need for regulation of these products by FDA. Youth may not be aware of the harmful effects of nicotine on the developing brain and the long term and short term health effects of vaping must be studied.”
As for the future of her research, Dr. Rezk-Hanna noted that research subjects have begun reporting that they add THC to hookah when vaping. THC, tetrahydrocannabinol, is the psychoactive chemical in cannabis and long-term health effects of cannabis use are only beginning to be studied. “Studying cannabis is an integral part of tobacco cessation,” says Dr. Rezk-Hanna. Indeed her recent study, using Wave 2 data from the Population Assessment of Tobacco and Health study (PATH), shows that e-hookah users are more likely to also co-use alcohol and cannabis than e-cigarette users.
Dr. Rezk-Hanna was awarded the 2019 Research Article of the Year from the AHA Council on Cardiovascular and Stroke Nursing. She received her BSN from George Mason University, and her MSN and PhD from UCLA.
