Alcohol Use and Infection May Trigger Ischemic Stroke

Although hypertension, atrial fibrillation, and other risk factors have been linked to stroke risk, conditions that could precipitate ischemic stoke (IS) are less well defined. The authors performed a systematic review of potential triggers for IS and identifying 12 factors in 26 studies (22 were case-control studies).

• There was a significant association between IS and alcohol consumption >40–60 g* in the preceding 24 hours (odds ratio [OR], 2.66) or >150 g† in the previous week (OR, 2.47).

• There was a significant association between IS and infection in the previous week (OR, 2.91) or in the previous month (OR, 2.41).

• Although the number of studies examining other precipitating factors was small, there was also a significant positive association between IS and anger, heavy eating, negative or positive emotions, sudden posture change in response to a startling event, birthday, and psychological distress.

• There was no significant association between IS and drug abuse or heavy physical exertion.

Comments:

Although regular moderate alcohol intake is associated with a reduced risk of IS in most cohort studies, this study found an increase in IS risk from drinking amounts some would consider moderate. Similarly, the risk of IS appears to increase following acute infections. As the authors point out, there are limitations to studying such relationships in case-control studies, and more case-crossover studies, where subjects serve as their own controls, are needed to better assess potential triggers of IS.

R. Curtis Ellison, MD

Reference:

Guiraud V, Amor MB, Mas JL, et al. Triggers of ischemic stroke: a systematic review. Stroke. 2010;41(11):2669–2677.