gms | German Medical Science

Objective: The neurotransmitter polypeptide Neuropeptide Y (NPY) is a potent vasoconstrictor; its role in the pathophysiology of spontaneous subarachnoid hemorrhage (SAH) has not yet been sufficiently yet. Recently, we reported on the correlation between NPY in CSF with vasospasm and outcome in 37 patients with spontaneous SAH. Here, we present the evaluation of the serum levels of NPY in this cohort and correlate the results to the clinical course and to the type of aneurysm treatment (clip or coil).

Methods: Thirty-seven patients with SAH were included and compared to a healthy control group (27 patients). Twenty-one patients met the doppler-sonography criteria for vasospasm and eighteen of these patients developed a stroke. In eighteen patients a craniotomy and clipping procedure were performed; in 14 patients the aneurysm was occluded with coils. All patients had an arterial catheter in the radial artery and blood was drawn daily for NPY analysis over a ten-day interval.

Results: The levels of NPY in serum were significantly higher after SAH than in the control group (p=0.001). The levels of NPY ranged significantly higher in patients with craniotomy and clipping than in the coiling group from days 3 to 10 (p=0.001). In fact, on day 1, we found a statistically significantly higher level of NPY in the serum of the 18 patients with vasospasm-related stroke over the time course of ten days (p=0.001).

Conclusions: We presume that retraction of the forebrain, opening of the Sylvian fissure and preparation of the aneurysm lead to excessive release of NPY in the systemic circulation. Furthermore, our data support the theory that NPY is increasingly due to vasospasm-related stroke after SAH. We suggest that NPY plays a major role in the pathophysiology of SAH.