The mean age of patients presenting with aSAH is increas- ing, which has been noted to have a negative impact on survival rates.59 Sex and racial variations in survival may also play a role in the variable rates, with some studies suggesting higher mortality in women than in men9,11,60 and higher mortality in blacks, American Indians/Alaskan Natives, and Asians/Pacific Islanders than in whites.63 Available population-based studies offer much less infor- mation about the functional outcome of survivors. Rates of persistent dependence of between 8% and 20% have been reported when the modified Rankin Scale is used.59 Although not population based, trial data show a similar picture, with 12% of patients in the International Subarachnoid Aneurysm Trial (ISAT) showing significant lifestyle restrictions (mod- ified Rankin Scale 3) and 6.5% being functionally dependent (modified Rankin Scale score of 4 5) 1 year after aSAH. Furthermore, scales that are relatively insensitive to cognitive impairment, behavioral changes, social readjustment, and energy level may substantially underestimate the effect of aSAH on the function and quality of life of surviving patients. Multiple studies using diverse designs have consistently demonstrated that intellectual impairment is very prevalent after aSAH. 