Pattern of subarachnoid haemorrhage in Saudi Arabia.

It has often been claimed that subarachnoid haemorrhage (SAH) is a rare condition in the Middle East. A 7-1/2-year retrospective study was undertaken to substantiate or disprove this claim. It was found that although the condition is less common than the global average, it was not as rare as previously supposed. The pattern of distribution throughout the population, in terms of sex, was significantly different. The possible reasons for this are discussed.