Type 2 Diabetes and Risk of Rupture of Saccular Intracranial Aneurysm in Eastern Finland

OBJECTIVE Type 2 diabetes is a risk factor for other forms of stroke, but its association with subarachnoid hemorrhage (SAH) from ruptured saccular intracranial aneurysm (sIA) has remained unclear. RESEARCH DESIGN AND METHODS Kuopio Intracranial Aneurysm Database (www.uef.fi/ns) includes all ruptured and unruptured sIA cases from a defined catchment population in eastern Finland since 1980. We compared the age-adjusted incidences of type 2 diabetes in 1,058 ruptured and 484 unruptured sIA patients during 1994-2008, using the national registry of prescribed medicine purchases. RESULTS Of the 1,058 ruptured sIA patients, 43% were males and 57% females, with a median age at rupture of 51 and 56 years, respectively. From 1994 to 2008 or until death, 9% had been prescribed antidiabetes medication (ADM) with a median starting age of 58 years for males and 66 years for females. Of the 484 unruptured sIA patients, 44% were males and 56% females, with a median age at the diagnosis of 53 and 55 years, respectively, and 9% had used ADM, with a median starting age of 61 years for males and 66 years for females. The incidence of type 2 diabetes was highest in the age-group 60-70 years, with no significant differences between the ruptured and unruptured sIA patients. CONCLUSIONS Our study suggests that type 2 diabetes does not increase the risk of rupture of sIA, which is by far the most frequent cause of nontraumatic SAH.