Association of SSRI and SNRI use with incident hyponatremia after subarachnoid hemorrhage

Abstract

Background

Hyponatremia is common following subarachnoid hemorrhage (SAH) and is associated with vasospasm and delayed cerebral ischemia (DCI). Risk factors for post-SAH hyponatremia are poorly defined; however, selective serotonin reuptake inhibitors (SSRIs) and selective norepinephrine reuptake inhibitors (SNRIs) are associated with hyponatremia in non-SAH populations. This study assessed whether pre-admission SSRIs/SNRIs were associated with hyponatremia after SAH.

Methods

This was a single-center retrospective study at a comprehensive stroke center. Patients were included if they were admitted for nontraumatic SAH (aneurysmal, perimesencephalic, or angiography-negative) and were excluded if they died within 24 h of presentation or were hyponatremic on admission. The primary endpoint was the incidence of hyponatremia. Key secondary endpoints included incidence of vasospasm, DCI, and rebleeding and discharge modified Rankin scale.

Results

292 patients were included; 49 patients were prescribed an SSRI or SNRI prior to admission. Of those included, 55.5 % had a Hunt and Hess score of 1 or 2, and 45 % of patients had anterior aneurysms. 11 % and 26 % of patients had perimesencephalic and CTA-negative SAH respectively. Hyponatremia occurred in 37 % of patients prescribed SSRIs/SNRIs vs 30 % of patients not on SSRIs/SNRIs (p = 0.36). Incidence of radiographic vasospasm in the SSRI/SNRI group was 33 % compared to 21 % in the non-SSRI/SNRI group (p = 0.065).

Conclusions

We did not find an association that reached our predefined statistical threshold between pre-admission SSRI/SNRI utilization and hyponatremia or secondary endpoints including vasospasm. This study suggests serotonergic therapies do not cause large effects on hyponatremia or clinically relevant complications after SAH.