A new paper published in JAMA Network Open discusses the trends in the use of e-cigarettes among American adults with pre-existing cardiovascular disease (CVD). Smoking tobacco is a widespread practice worldwide, despite numerous reports of its ability to endanger human health and shorten human life.
Recently, electronic cigarettes have come into fashion, especially following their promotion as useful tools to support smoking cessation. However, their use has been linked to worsening cardiovascular health.
Given the reported cardiovascular hazards of e-cigarettes, smoking cessation, rather than e-cigarette substitution, may be more beneficial for cardiovascular secondary prevention.
Wen et al. (2023)
The e-cigarette is considered by many to be safer than conventional cigarettes, leading it to be recommended as a smoking cessation tool. Instead of burning tobacco, a liquid formulation is electronically heated to produce a cocktail of fumes that is inhaled by the user.
The ability to choose among various flavors and nicotine concentrations has further wooed the consumer market. However, the process of heating various chemicals like propylene glycol and glycerin to the point of vaporization has been reported to produce new decomposition compounds, some of which are dangerous to lung tissue.
For instance, acrolein is a potent herbicide and is known to be associated with acute lung injury and chronic obstructive pulmonary disease (COPD).
The cardiovascular effects of e-cigarettes include oxidative stress, endothelial injury, systemic inflammation, enhanced platelet activation, and arterial stiffening. These effects are associated with various chemical by-products known to be present in e-cigarette fumes. Some of these chemicals are actual or potential carcinogens.
E-cigarettes were introduced to the American market in 2006, following which users have increased rapidly across age groups.
They have chiefly been promoted as aids to quitting smoking, which is known to be a risk factor for CVD, cutting short the expected lifespan by about a decade. However, this promotion overlooks documented facts related to e-cigarettes themselves being addictive and potentially contributing to worsening CVD.
The current study looked at how the use of e-cigarettes is growing among American adults who have already developed CVD. This could help shape future laws and regulations in this important area of public health.
What did the study show?
The study used public data from the National Health Interview Survey. There were approximately 30,500 participants with a mean age of 65 years. About 48% were female and 85% were white.
The data shows decreasing use of e-cigarettes from 2014 to 2019, from 5% to 3% respectively. This trend reversed itself thereafter, returning to 5% in 2020. This has been attributed to the onset of the coronavirus disease 2019 (COVID-19) pandemic. However, this is unlikely since the pandemic was declared in March 2020.
Ex-smokers with CVD who used e-cigarettes increased from 3% in 2015 to 19% in 2020. Among older patients (those aged 60 years or more), almost 3% used e-cigarettes in 2014, but this declined to <1% in 2020. The opposite trend is observable among younger patients, those below 60, with the prevalence being 6% and 7% in 2014 and 2020, respectively.
Men outnumbered women in their use of e-cigarettes before 2018, but in both 2019 and 2020, the reverse trend occurred. In fact, in 2020, over 8% of women but less than 3% of men used e-cigarettes.
Both ex-smokers and those who tried to quit but failed were at twice the odds for e-cigarette use compared with current smokers. This confirms the observation that e-cigarettes are most often used among CVD patients as an aid for smoking cessation, as is the case for general users.
What are the implications?
While e-cigarettes may help cut down on conventional smoking, it is not yet clear whether their use is heart-friendly or promotes an improvement in cardiovascular health compared to the use of conventional cigarettes.
The current study shows an increasing shift towards the use of e-cigarettes among young people and women, among those with prior CVD.
Further studies are needed to understand the cardiovascular effects of e-cigarettes compared with combustible tobacco to inform future legislation for cardiovascular health.
Wen et al. (2023)