Sex differences in the clinical manifestations and treatment outcomes in a large cohort of spontaneous intracranial hypotension

Objective: To determine sex differences in clinical profiles and treatment outcomes in patients with spontaneous intracranial hypotension. Background: Spontaneous intracranial hypotension is associated with considerable functional disability and potentially fatal complications, and it is uncertain whether males and females should be managed differently. Methods: This was a cohort study of consecutive patients with spontaneous intracranial hypotension enrolled from a medical center. Medical records and imaging findings were reviewed. The outcome of treatment responses to epidural blood patches and risks of subdural hematoma were measured. Results: In total, 442 patients with spontaneous intracranial hypotension (165 males, 277 females) were included in the analysis. Males were more likely to have a delayed (>30 days) initial presentation than females (32.1% [53/165] vs. 19.9% [55/277], p = 0.004), and males were less likely to have nausea (55.8% [92/165] vs. 67.1% [186/277], p = 0.016), vomiting (43.0% [71/165] vs. 54.2% [150/277], p = 0.024), photophobia (9.7% [16/165] vs. 17.0% [47/277], p = 0.034), and tinnitus (26.7% [44/165] vs. 39.7% [110/277], p = 0.005) compared with females despite comparable radiologic findings. Among the 374 patients treated with epidural blood patches, males were more likely to be nonresponders to the first epidural blood patch (58.0% [80/138] vs. 39.0% [92/236], OR = 2.2, 95% CI = 1.4–3.3, p < 0.001). Males were at a higher risk of having subdural hematoma (29.7% [49/165] vs. 10.8% [30/277], OR = 3.5, 95% CI = 2.1–5.8, p < 0.001). Among patients with subdural hematoma, males had greater thickness (12.8 ± 4.3 vs. 8.1 ± 5.9 mm, p < 0.001) and were more likely to receive surgical drainage (55.1% [27/49] vs. 10.0% [3/30], OR = 11.0, 95% CI = 3.0–41.3, p < 0.001) than females. Conclusion: In the present study, spontaneous intracranial hypotension in males was characterized by a delayed presentation, poorer response to the first epidural blood patch, and a higher risk of subdural hematoma. Caution should be exercised in the management of males with spontaneous intracranial hypotension. The generalizability of the findings needs to be further confirmed.