What is the association between smoking and risk of stroke?
Multiple meta-analyses and studies have found that smoking is associated with increased risk of stroke. This has been demonstrated in both active and passive smokers. For example, a meta-analysis of 36 studies found that active smoking increases the risk of stroke by 40-50%, whereas passive smoking was associated with an increased risk of stroke of 20-30% (Lee et al, 2017). Another study found that there is a dose-dependent relationship between the amount of smoking and risk of stroke, with the risk increasing as the amount of smoking increases (Pan et al, 2019). Therefore, it is clear that smoking is associated with increased risk of stroke.