Smoking Directly Linked to Subarachnoid Haemorrhage in Large, Long-Term Study of Twins

September 18, 2020
A study published in Stroke provides strong evidence for a casual, rather than associative, role of smoking in subarachnoid haemorrhage (SAH). The findings suggest that SAH has more to do with external risk factors and very little to do with genetic influence. “Our study provides further evidence about the link between smoking and bleeding in the brain,” said Ilari Rautalin, University of Helsinki, Helsinki, Finland. The researchers utilised healthcare data from the Finnish Twin Cohort, a national database of 32,564 individuals (16,282 same-sex, twin pairs in Finland) who were born before 1958 and alive in 1974, and followed for over 42 years between 1976 and 2018. There were a total of 120 fatal bleeding stroke events among the twins, and the strongest link for a fatal brain bleed was found among smokers. Data collected from surveys included smoking, hypertension, physical activity, body mass index, education, and alcohol use. Participants were separated into 2 groups: smokers (occasional or current) or non-smokers (never and former). Current smokers were classified according to the number of cigarettes smoked per day: light (https://www.ahajournals.org/doi/10.1161/STROKEAHA.120.031231 SOURCE: American Stroke Association