Clinical Outcome and Prognostic Factors of Patients with Perimesencephalic and Nonperimesencephalic Subarachnoid Hemorrhage

To demonstrate the clinical outcome of patients with nonperimesencephalic subarachnoid hemorrhage (npSAH) compared with patients with aneurysmal SAH (aSAH) and perimesencephalic SAH (pSAH) and to evaluate predictive value of various clinical and radiological findings in patients with npSAH.We retrospectively identified patients with SAH who presented at our institution between 2009 and 2018. We analyzed demographic and clinical data and outcomes. Multivariable analysis was performed for outcome parameters.Of 608 patients with confirmed SAH, 78% had aSAH, and 22% had nonaneurysmal SAH. Nonaneurysmal SAH was perimesencephalic in 30% of cases and nonperimesencephalic in 70%. Initial clinical status (Hunt and Hess score) was significantly worse in patients with aSAH compared with patients with nonaneurysmal SAH. Complications such as delayed cerebral ischemia occurred significantly more often in patients with aSAH. Patients with pSAH had a more favorable clinical course than patients with aSAH or npSAH. There was no significant difference in 30-day mortality between aSAH (29%) and npSAH (28%) patients (P = 0.835). Hunt and Hess score emerged as a strong predictor of unfavorable outcome in both aSAH and npSAH in multivariable regression.Patients with npSAH had a similar clinical outcome as patients with aSAH, although there were significantly fewer clinical complications in patients with npSAH. Patients with pSAH demonstrated an overall good clinical course. Our multivariable analysis showed that initial Hunt and Hess score was an important predictor for clinical outcome in aSAH as well as npSAH.