•  
  •  
 

Abstract


ABSTRACT

Electronic cigarettes (e-cigs) are popular with smokers looking for a healthier alternative to tobacco cigarettes. E-cigs utilize a battery, activated on inhalation, to heat propylene glycol-suspended nicotine which is inhaled as vapor, and which does not include harmful poisons found in conventional cigarettes. Although the health claims of e-cigs continue to be debated, the effects of nicotine delivered as vapor on the cardiovascular system have not been studied. Because nicotine is a sympathomemetic agent, we tested the hypothesis that e-cigs would increase arterial pressure and protect against challenges associated with upright posture. Ten non-smoking subjects (5 male) participated in two experimental trials, separated by one week (randomized). Seated blood pressures were taken after a 10 min quiet rest period, and then subjects either inhaled (once every 30 s for 10 min) on an e-cig with a placebo cartridge (0 mg nicotine) or an active cartridge (18 mg nicotine). After an additional 10 min quiet seated rest, we measured blood pressure again, and then subjects provided a urine sample for analysis of cotinine (a nicotine biomarker). We recorded ECG and finger photoplethysmographic arterial pressure. Subjects breathed to a metronome set at 15 breaths/min for 5 min supine, 5 min head-up (70o), and 5 min supine (recovery). Cotinine readings failed to register the presence of nicotine in urine, but a majority of subjects experienced dizziness and nausea after the active, but not the placebo cartridge. Seated arterial pressures were similar after the placebo cartridge (p ≥ .05), but increased from 112 ± 3/62 ± 2 mmHg to 115 ± 3/67 ± 3 after the nicotine cartridge (p ≤. 05). Systolic and diastolic pressures were higher (all p ≤ .05) after the nicotine trial compared to placebo for supine (115 ± 3/69 ± 2 vs. 106 ± 4/62 ± 2 mmHg), tilt (105 ± 4/66 ± 3 vs. 93 ± 4/60 ± 3 mmHg), and recovery (117 ± 5/72 ± 2 vs. 106 ± 4/64 ± 3 mmHg). No subject experienced presyncope during tilt for either trial. We show, for the first time, that inhalation of vaporized nicotine increases arterial pressure in the seated, supine and head-up tilt positions - suggesting sympathomemetic properties. Although mild, acute increases in arterial pressure may seem harmless, it is possible that daily, continuous use of e-cigs could result in consistently elevated arterial pressure, resulting in higher afterload and chronic cardiac strain.

Share

COinS
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.