In a new study published in the journal eClinicalMedicine, researchers have explored in detail how varied smoking habits influence the risk of getting a stroke.
It found that current smokers are at a higher risk of getting a stroke compared to those who never smoked, with the association being stronger for ischaemic stroke, the most common kind and caused when blood fails to reach the brain. The international study included researchers from St John's Medical College and Research Institute, Bangalore.
Both filtered and non-filtered cigarettes were linked with increased stroke risk and passive smoking. Exposure to environmental tobacco smoke (ETS) for more than ten hours a week was found to nearly double the stroke risk, especially that of ischaemic and intracerebral hemorrhage (ICH).
The team also found that in young heavy smokers (more than 20 cigarettes a day) under 50 years of age, stroke risk more than doubled, which was higher compared to increasing 1.5-fold in participants aged 70 and above. Among those aged 50-59, they observed an 8-fold risk increase of large vessel stroke involving large vessels supplying blood to the brain.
The data of participants from 32 high-, middle—and low-income countries, including those from Africa, South Asia (India and Pakistan), and South America, were analysed. They were recruited from January 2008 to August 2015.
The researchers also found that across income levels, stroke risk from smoking was higher in high-income countries (HICs) than low- and middle-income countries (LMICs), with younger smokers at higher risk than older ones. The risk of stroke rose with the number of cigarettes smoked per day, especially in HICs, they said. The study findings are relevant to global efforts directed at reducing tobacco use and exposure, the researchers said.
