Background: Perimesencephalic and nonperimesencephalic nonaneurysmal subarachnoid hemorrhage (PM-naSAH and NPM-naSAH) have a different bleeding pattern and clinical course. The etiology and risk factors for PM-naSAH and NPM-naSAH are unclear. The objective of this study was to compare risk factors and triggering events between PM-naSAH and NPM-naSAH.
Methods: We reviewed retrospectively all patients (n = 3475) who had undergone cerebral digital subtraction angiography between 2003 and 2020 at our tertiary hospital. Of these, 119 patients had 6-vessel angiography negative subarachnoid hemorrhage (47 (39%) PM-naSAH and 72 (61%) NPM-naSAH) and accurate information about the triggering event was available in 42 (89%) PM-NASAH and 64 (89%) NPM-naSAH patients.
Results: PM-naSAH were younger compared to NPM-naSAH (mean age [SD]; 55.3 [11.1] years vs. 59.6 [12.2] years, p = .045. PM-naSAH was triggered during the physical exertion in 79% of patients and 16% of patients with NPM-naSAH (relative risk 5.4; 95% CI, 2.9-10.1, p < .0001). There were no significant difference in sex, smoking, alcohol abuse, hypertension, diabetes, hyperlipidemia, or anticoagulation/antithrombotic usage between PM-naSAH and NMP-naSAH, p > .05.
Conclusion: Physical exertion was a triggering factor in most of the PM-naSAH cases and the risk was five times greater than in NMP-naSAH. More studies are needed to confirm our results and to study pathophysiology of PM-naSAH and NPM-naSAH.
Keywords: nonaneurysmal subarachnoid hemorrhage; perimesencephalic subarachnoid hemorrhage; physical exertion; risk factors.
© 2022 The Authors. Brain and Behavior published by Wiley Periodicals LLC.