PHILADELPHIA – Researchers of two recent studies on the safety of electronic (e-) cigarettes revealed that e-cigarette use is associated with abnormal coronary vascular function that may be worse than smoking traditional cigarettes and showed that adverse lipid and glucose profiles were similar to traditional cigarette use. These studies were presented at American Heart Association 2019 Scientific Sessions, held November 16 to 18, in Philadelphia, Pennsylvania.1,2
In one study, the investigators sought to examine the cardiovascular effects associated with e-cigarette use by analyzing myocardial blood flow as a measure of coronary vascular function. In a group of healthy volunteers (mean age, 28±4 years), 10 were self-reported chronic e-cigarette users and 9 were traditional cigarette users. Participants abstained overnight and after exposure to 1 use of a popular e-cigarette (15 puffs in 7 minutes) or 1 Camel Filtered cigarette, underwent myocardial contrast echocardiography to detect acute increases in myocardial blood flow. The procedure was repeated after performing handgrip exercises to induce physiologic stress to measure sympathetically mediated increases in myocardial work and oxygen demand.
Following inhalation, myocardial blood flow increased moderately in traditional cigarette smokers as did the myocardial demand for oxygen; however, despite greater oxygen demand, myocardial blood flow decreased notably with physiologic stress. In e-cigarette users, myocardial blood flow decreased both at rest and following hand-grip exercises, indicating persistent coronary vascular dysfunction even in the absence of stress. The investigators suggested further studies should be done to evaluate the potential harm to chronic e-cigarette users, especially in individuals at risk for cardiovascular disease.
In a second study, investigators sought to understand the impact of e-cigarettes specifically on lipids and glucose levels, as traditional cigarettes are known to affect these. Participants without established cardiovascular disease were categorized as nonsmokers (n=94), sole e-cigarette smokers (n=45), dual e- and traditional cigarette users (n=52), or traditional cigarette smokers (n=285). Investigators collected demographic data and measured fasting lipid and glucose levels of all participants.
E-cigarette users were often current or former smokers, and compared with traditional smokers, they were typically younger, more likely to be men, and less likely to be black.
Participants who used tobacco products had higher glucose, total cholesterol, triglycerides, low-density lipoproteins, and very-low density lipoprotein cholesterol levels and lower high-density lipoprotein cholesterol levels.
In multivariable regression analysis (adjusting for age, race, and gender), sole e-cigarette use remained associated with elevated total cholesterol, triglycerides, and low-density lipoprotein cholesterol when compared with nonsmoking (P <.05). Lower high-density lipoprotein cholesterol was associated with dual e-cigarette and traditional cigarette (P <.01). The investigators concluded that e-cigarettes produce an adverse metabolic affect similar to traditional smoking.
“Providers counseling patients on the use of nicotine products will want to consider the possibility that e-cigs may confer as much and potentially even more harm to users and especially patients at risk for vascular disease,” added study co-author Susan Cheng, MD, in a press release.3
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
- Rashid M, Davoren K, Moy NB, et al. Chronic e-cigarette users demonstrate more persistent coronary endothelial dysfunction than chronic combustible cigarette users. Presented at: American Heart Association 2019 Scientific Sessions; November 16-18, 2019; Philadelphia, PA. Abstract 14980.
- Majid S, McGlasson KL, Fetterman JL, et al. Electronic cigarette use is associated with altered lipid profiles in the CITU study. Presented at: American Heart Association 2019 Scientific Sessions; November 16-18, 2019; Philadelphia, PA. Abstract 14816.
- E-cigarettes take serious toll on heart health, not safer than traditional cigarettes [news release]. Dallas, TX: American Heart Association. Published November 11, 2019. https://newsroom.heart.org/news/e-cigarettes-take-serious-toll-on-heart-health-not-safer-than-traditional-cigarettes. Accessed November 14, 2019.