Background: Non-aneurysmal, non-traumatic subarachnoid hemorrhage (nSAH) refers to cases where a causative aneurysm cannot be identified. We studied six-months outcomes in nSAH patients. Methods: From a prospective SAH registry of all nSAH patients admitted between 2012 and 2023, relevant complications and outcomes were collected. Functional outcome and return-to-work at six months were assessed using the modified Rankin Scale (mRS), quality of life with the EuroQol-5Dimensions (EQ-5D) and Hospital Anxiety & Depression Scale (HADS), and an institutional 14-item questionnaire for assessment of residual symptoms. Results: 325 consecutive nSAH patients were included (191 non-perimesencephalic, non-aneurysmal subarachnoid hemorrhage [NPSAH]; 134 perimesencephalic subarachnoid hemorrhage [PMSAH]). 303 (93%; 179 NPSAH and 124 PMSAH) were available at follow-up (7 patients died). Favorable functional outcome (mRS-score 0-2) was reported in 271 (89%) patients and did not differ between NPSAH- and PMSAH. 141 (77%) patients returned to work, whereas only 71 (39%) patients reached their previous level of work. PMSAH patients were more likely to return to work (68/96 (71%) NPSAH and 73/87 (84%) PMSAH, respectively, p=0.01). Furthermore, PMSAH patients were more likely to fully return to work (p=.034). The mean (SD) EQ-5D and EQ-VAS scores were 0.827 (0.184) and 74 (16), respectively. The HADS-A and -D scores were deviant (score >7 points) in 53 (23%) and 48 (21%) patients, respectively. Only 39 patients (16%) denied experiencing residual symptoms. Increased fatigue (n=164; 68%), increased concentration difficulties (n=130; 54%), and increased forgetfulness (n=121; 50%) were the most frequently reported residual symptoms. Conclusions: This study reveals that the majority of nSAH patients reports residual symptoms and did not return to their previous level of work at six months follow-up, despite a favorable functional outcome. These findings nuance the perception of a good outcome, as suggested in previous studies, warranting further research on possible rehabilitative interventions and counseling in these patients.

Jonathan Coutinho received financial support from the Dutch Heart Foundation, Medtronic, Bayer and Boehringer (all fees were paid to his employer), and is co-founder and shareholder of TrianecT. René van den Berg reports a consultancy agreement with Cerenovus (Johnson & Johnson).

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This study was waived for ethical approval by the Institutional Review Board of the Amsterdam UMC because it did not fall under the scope of the Medical Research Involving Human Subjects Act (WMO). This study was completed in accordance with the Helsinki Declaration as revised in 2013.

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