Background
There is substantial interest in the cardiovascular effects of e-cigarette use, highlighting the need to update our knowledge on the subject. We conducted this review to analyse whether e-cigarette use increases cardiovascular health risks and how these risks vary among different populations.
Methods
We searched six databases and included peer-reviewed human, animal, cell/in vitro original studies but excluded qualitative studies, which were published between July 2021 and December 2023. Three types of e-cigarette exposure were examined: acute, short-to-medium term and long term. Different risk of bias tools were used for assessing the quality of the included human studies and we conducted meta-analysis when possible.
Results
We included 63 studies in the main analysis, 12 studies in the meta-analysis and 32 studies in the sociodemographic factor-based subgroup analysis. Over half of the human studies had low risk of bias. Acute exposure to e-cigarette was associated with increased heart rate (HR) (mean difference (MD) 11.329, p<0.01) and blood pressure (BP) (MD 12.856, p<0.01 for systolic; MD 7.676, p<0.01 for diastolic) compared with non-use. While HR was lower after acute exposure to e-cigarettes compared with cigarettes (MD –5.415, p<0.01), no significant difference in systolic or diastolic BP was observed. Non-smoker current vapers had no significant differences in resting HR and BP compared with non-users but lower resting HR (MD –2.608, p<0.01) and diastolic BP (MD –3.226, p<0.01) compared with non-vaper current smokers. Despite some association between e-cigarette and endothelial dysfunction, short-to-medium-term transition from cigarettes to e-cigarettes may improve blood flow and BP, particularly among females and younger individuals. There is lack of evidence supporting any association of e-cigarette use with cardiovascular diseases and cardiac dysfunction or remodelling.
Conclusions
This review highlighted several important cardiovascular impacts of e-cigarette use compared with non-use and cigarette smoking. However, the evidence is still limited and requires future research.
PROSPERO registration number
CRD42023385632.
