Racial differences between Maori and European New Zealanders in aneurysmal subarachnoid haemorrhage.

Racial differences in the incidence and rate of rupture of intracranial aneurysms are well recognized. A retrospective study of racial differences between Maori and European New Zealanders presenting to the Auckland Regional Neurosurgical Unit between 1985 and 1990 was conducted. It was found that the incidence per 100,000 of the population for all aneurysms was 14.3 for Europeans and 25.7 for Maoris. The mean age at rupture was 10 years earlier in Maoris with single aneurysms. A strong association between aneurysmal subarachnoid haemorrhage and cigarette smoking was found in both groups not only for single, but also for multiple aneurysms. Maoris were also found to have an abnormally high incidence of middle cerebral artery aneurysms and a low incidence of vertebrobasilar ones compared with Europeans.