Acute inhalation of vaporized nicotine increases arterial pressure in young non-smokers: a pilot study

Introduction:
This text is a summary of a study on the acute effects of vaporized nicotine inhalation delivered by electronic cigarettes on arterial pressure and autonomic control in healthy, non-smoking human subjects. The study found that nicotine inhalation is associated with elevated arterial pressures in the seated position and increased arterial pressures in the supine and head-up positions compared with the placebo condition. The study also found that functional autonomic control is not affected by nicotine inhalation during head-up tilt.

Key points:

* The study had 20 healthy, non-smoking participants who were exposed to either nicotine or placebo cartridges in a double-blind, randomized, counterbalanced design.
* After inhaling nicotine for 10 minutes, 19 of the 20 participants reported feeling lightheaded, and 3 reported nausea. No symptoms were reported after inhaling the placebo cartridge.
* Urine cotinine concentrations, an index of metabolized nicotine, were significantly higher after nicotine inhalation compared with the placebo cartridge.
* Baseline arterial pressures and heart rates before inhalation on either the nicotine or placebo cartridge were not different. However, after the inhalation protocol, heart rate and systolic pressure increased in the nicotine condition, resulting in higher heart rates and systolic pressure compared with the placebo trial.
* Systolic and diastolic pressures were higher after nicotine inhalation in each posture during the head-up tilt protocol.
* Vagal-cardiac control, as assessed by R-R intervals and RRISD, decreased with tilt, but reductions were similar between conditions.
* MSNA was numerically higher after nicotine inhalation compared with placebo in the supine position, but not statistically distinguishable. Head-up tilt increased both MSNA burst incidence and frequency, but this difference was not distinguishable statistically between conditions.

Main message:
The study suggests that inhalation of vaporized nicotine delivered by electronic cigarettes increases arterial pressures acutely but does not affect autonomic cardiovascular control under conditions of orthostatic stress. Although vaporized nicotine was associated with acute increases of blood pressure, the potential effects of chronic use in healthy non-smokers are not known and should be explored. The study highlights the need for further research on the potential health effects of electronic cigarettes, particularly in young non-smokers. The symptoms reported by the participants after nicotine inhalation suggest that non-smokers are sensitive to nicotine as delivered in this protocol. Therefore, regulations and restrictions on the use of electronic cigarettes, especially among young non-smokers, are necessary to protect public health.

Cooke, William H., Anusheela Pokhrel, Colin Dowling, Donovan L. Fogt, and Caroline A. Rickards. “Acute Inhalation of Vaporized Nicotine Increases Arterial Pressure in Young Non-Smokers: A Pilot Study.” Clinical Autonomic Research 25, no. 4 (August 2015): 267–70. https://doi.org/10.1007/s10286-015-0304-z.