Does vaping cause cardiovascular disease?
Posted on August 14, 2024 By Colin
WHILE VAPING MAY POSE A RISK of cardiovascular harm, such as heart attacks or strokes, there is currently no definitive evidence to confirm this. Long-term epidemiological studies are needed to provide more conclusive answers.
However, the potential harm is likely to be small in most cases and significantly less than that caused by cigarette smoking. The risk is greatest in heavy or long-term vapers and those with pre-existing cardiovascular conditions.
In contrast, the evidence is clear that switching from smoking to vaping substantially reduces the risk of cardiovascular disease
The evidence
Cross-sectional studies
Cross-sectional studies provide a snapshot of a population at a single point in time. While they can identify associations between vaping and health outcomes, they cannot determine whether vaping caused those outcomes.
Some cross-sectional studies have reported an association between vaping and a higher risk of cardiovascular issues compared to non-vapers. (Sharma; Alzaharani; Farfan; Vindyal) However, in many instances, participants who vaped had a history of smoking, and the increased harm may be attributed to their previous smoking habits. In some studies, cardiovascular events occurred before the onset of vaping.
Other cross-sectional studies have not identified any increased risk. One study of 450,000 subjects found that people who vaped but had never smoked had no increased risk. (Osei) Another study of 60,000 subjects found no increased incidence of heart disease in vapers compared to non-vapers. (Farsalinos)
Longitudinal studies
Longitudinal studies follow subjects over time. They are more robust and provide more reliable information.
A study of 24,000 subjects found that vapers who had never smoked had the same risk as non-vapers after five years follow-up. (Berlowitz) Another study found that vapers did not have an increased incidence of heart attack or stroke compared to non-vapers and non-smokers after five years. (Hirschtstick)
Cross-sectional and longitudinal studies
An analysis of 20 studies (14 cross-sectional and 6 longitudinal) involving nearly 9 million people did not find an increased incidence of cardiovascular disease in people who exclusively vaped compared to those who had never vaped or smoked. (Chen) The authors point out that this study does not prove that vaping is risk-free to the cardiovascular system - longer studies may be needed to identify harms.
Dual use
Numerous studies have found that dual use (smoking and vaping) significantly increases the risk of cardiovascular disease. (Chen; Berlowitz)
Does switching to vaping improve heart health?
The harm to the cardiovascular system from smoking far outweighs any potential risks from vaping (Peruzzi; Ding; Sharma)
Switching from smoking to vaping has been shown to reduce cardiovascular risk. Research has documented improvements in cardiovascular health in the short term (Caruso), within one month (George), and also at three and six months. (Klonizakis)
Studies have demonstrated significant improvements in blood pressure control among smokers with hypertension who switch to vaping, with benefits observed at a 12-month follow-up. (Farsalinos; Polosa) Additionally, both heart rate and blood pressure tend to decrease after switching from smoking to vaping. (OHID p956, 963)
Biological Plausibility: How might vaping cause harm?
While most of the toxic chemicals found in cigarette smoke are absent from e-cigarette vapour, some toxicants are present which could impact cardiovascular health. These include acrolein, oxidizing chemicals, volatile organic compounds (such as acrolein and benzene), and trace metals. However, these substances are present at much lower levels in vapor than in smoke. (OHID)
Studies in cells, animals and humans have found that vapour can affect cardiovascular health in several ways, the most potent being oxidising stress (harm to blood vessels from free radicals). Other mechanisms of harm include inflammation, sympathetic activation (increased pulse rate and blood pressure), platelet activation (increased stickiness in platelets leading to blood clots), harm to blood fats and endothelial dysfunction (damage to the lining of the arteries).
The risk to to human health from these findings is possible but uncertain. (Benowitz) Importantly, these effects are less pronounced compared to those caused by smoking. (Middlekauff; Ikonomidis)
What about the effect of nicotine?
Nicotine has well-documented effects on the cardiovascular system and could pose a risk for people with existing cardiovascular conditions. (Benowitz) However, these risks are much lower than those associated with smoking.
Nicotine increases heart rate and blood pressure, makes the heart work harder, and constricts blood vessels. It can also trigger arrhythmia (irregular heartbeat), cause insulin resistance (leading to elevated blood glucose levels) and may result in lipid (blood fat) abnormalities. Additionally, nicotine might damage the lining of the arteries. (Benowitz)
However, in the short term, nicotine use appears to pose minimal risk. A review of 42 clinical trials using nicotine products for up to 12 weeks found no significant increase in cardiovascular events. (Kim)
Furthermore, long-term users of Swedish snus (a product that delivers high doses of nicotine) do not have higher rates of heart attack or stroke compared to non-users. (Hansson)
Conclusions
There is strong evidence that smokers who switch to exclusive vaping substantially reduce their risk of cardiovascular disease.
There is no good evidence that exclusive vaping increases cardiovascular disease, although longer studies are needed to confirm this. Nevertheless, it is best not to vape if you are not a smoker or former smoker.
Dual use (smoking and vaping) significantly increases cardiovascular risk.