Alcohol in e-Cigarettes May Impair Motor Skills

Megan Brooks

January 20, 2016

UPDATED January 20, 2016 // Some e-cigarettes contain enough alcohol (used to vaporize nicotine) to affect motor skills, without the user knowing it, new research shows.

"e-Cigarettes are not regulated right now, and this study raises major questions about the acute and long-term safety of e-cigarettes. It's one thing to drink alcohol, it's another thing to inhale it," senior investigator Mehmet Sofuoglu, MD, PhD, Department of Psychiatry, Yale University School of Medicine and VA Connecticut Healthcare System, told Medscape Medical News.

"We didn't do a driving simulation, but you kind of have to wonder whether people using e-cigarettes would have impaired driving," he added.

The study was published online December 24 in Drug and Alcohol Dependence.

Unaware of Motor Effects

The researchers studied 21 adults aged 21 to 35 years who reported drinking socially and using an e-cigarette at least once in the past year. They had them puff from two commercially available e-cigarettes containing either high (23.5%) or low (0.4%) amounts of alcohol and measured acute changes in subjective drug effects, psychomotor performance, and alcohol metabolites in urine.

Although neither group reported feeling differently after inhaling the vapor, "performance on the Purdue Pegboard Dexterity Test improved under the trace, but not under the 23.5% alcohol condition," the researchers report.

"What struck us," Dr Sofuoglu said, "is that they didn't feel like they had any subjective drug effects" after using the e-cigarette with high alcohol content, yet there was a decline in psychomotor performance compared with individuals who used the e-cigarette with only a trace amount of alcohol.

Although plasma alcohol levels remained undetectable during testing, three participants had measurable levels of an alcohol metabolite in their urine after puffing from the e-cigarette with 23.5% alcohol. "So there was also some biochemical evidence that people were actually getting alcohol, and this was impairing their psychomotor performance," Dr Sofuoglu said.

"To our knowledge, no previous studies have systematically examined the acute effects of alcohol inhaled from an e-cigarette," the investigators note in their report, and the prevalence and patterns of alcohol exposure from e-cigarette use remain unknown.

About 75% of the commercial e-cigarette liquids the researchers tested contained less than 1% alcohol. However, anecdotal evidence from the Internet suggests that some e-cigarette users "spike" their e-liquids with various types of alcohol, and alcohol may be deliberately added to e-liquids to thin viscous solutions, as recommended by do-it-yourself e-liquid forums, they say. In addition, "alcohol e-cigarettes" may soon be coming on the market.

"Consequently, whether from commercially prepared products or from self-made e-liquids, many e-cigarette users are likely repeatedly inhaling variable levels of alcohol during routine e- cigarette use," the investigators note.

"Given the widespread and unregulated use of e-cigarettes, especially by youth and other vulnerable populations, further studies are needed to evaluate both the acute safety and long-term health risks of using alcohol-containing e-cigarettes," the investigators conclude.

The presence of alcohol in e-cigarettes might reinforce the addictive properties of both nicotine and alcohol if inhaled, they note. It is also "concerning," Dr Sofuoglu said, that people in recovery from alcohol addiction could be exposed to a small dose of alcohol without knowing it.

Invalid Conclusion

Michael Siegel, MD, MPH, professor, Department of Community Health Sciences, Boston University School of Public Health, in Massachusetts, who reviewed the study for Medscape Medical News, has strong reservations about the study.

"After reviewing the study, I have to question the validity of the conclusions. Specifically, I do not believe the conclusions of the study are supported by its actual findings. The results of this study do not provide a solid basis to conclude that vaping a high-alcohol e-liquid impairs motor performance," Dr Siegel said.

"This article," he noted, "concludes that vaping high-alcohol e-liquids causes motor impairment that could lead to motor vehicle crashes from alcohol intoxication, despite finding that there was no alcohol detectable in the blood of high-alcohol e-liquid vapers. This extrapolation is not warranted, and therefore, the study conclusions are not valid."

Funding for the study was provided by the New England Mental Illness Research, Education, and Clinical Center, the Department of Veterans Affairs, the National Institute for Drug Abuse, and the FDA Center for Tobacco. The authors have disclosed no relevant financial relationships.

Drug Alcohol Depend. Published online December 24, 2015. Abstract


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