Soy products and risk of an aneurysmal rupture subarachnoid hemorrhage in Japan.

Background: The aim of this study was to explore the relationship between soy products and the risk of subarachnoid hemorrhage in a case-control study.

Design: A case-control study was conducted.

Methods: Incident subarachnoid hemorrhage cases (n = 201) were identified and individually matched on age (+/- 2 years) and sex to community (n = 201) controls from April 1992 to March 1997. A factor analysis was conducted to identify dietary patterns in relation to subarachnoid hemorrhage risk.

Results: Soy-rich products were significantly associated with a decreased risk of subarachnoid hemorrhage (lowest versus highest quartile, adjusted odds ratio 0.46; 95% confidence interval 0.18-0.88).

Conclusion: The findings suggest that a diet high in soy products may be protective against the development of subarachnoid hemorrhage.