The variation in the effect of alcohol consumption on different types of stroke may be ascribed to the difference in the causes of haemorrhagic and ischaemic stroke. Ischaemic stroke is caused by the blockage in a blood vessel in the brain, commonly arising from a blood clot formed somewhere else, and therefore has a similar aetiology to that of IHD (for biological pathways see IHD above). Consequently, a pattern of irregular heavy drinking occasions should also have the same detrimental effects as for IHD. Thus, combining fatal and non-fatal ischaemic strokes in a Finnish cohort study, Sundell and colleagues [156] reported a RR of 1.99 (95% CI: 1.39 to 2.87) for ischaemic stroke among participants whose drinking pattern included binge drinking occasions (defined as 6+ drinks in one setting for men or 4+ drinks for women, equivalent to 72 g and 48 g of pure alcohol respectively) compared to non-binge drinkers after adjusting for long-term average alcohol consumption, age and sex. An RR of 1.56 (95% CI: 1.06 to 2.31) was estimated, when hypertension, study area, smoking, diabetes, BMI, education, history of MI, and study year were taken into account as well.
