“Cigarette smoking has been directly correlated with an increased risk of intracranial aneurysm formation and growth,” the authors say.

RE:  “And despite this evidence, more than one third of prior smokers continue to use nicotine after suffering an aneurysm, especially patients who started smoking at a young age and those with a history of depression or alcohol abuse.”

Were contributing factors of history of depression without smoking or alcohol abuse without smoking noted as being correlated to increased risk as well?  Besides smoking, were there other defined risks associated with formation of aneurysms?

Could you tell me the study group size and the statistical error factors?

Thank you.