ADMA Levels and Arginine/ADMA Ratios Reflect Severity of Disease and Extent of Inflammation After Subarachnoid Hemorrhage

Abstract

Subarachnoid hemorrhage (SAH) is characterized by an inflammatory response that might induce endothelial dysfunction. The aim of this study was to evaluate if ADMA and arginine/ADMA ratios after SAH (indicators of endothelial dysfunction) are related to clinical parameters, inflammatory response, and outcome. Prospective observational study. ADMA, arginine, C-reactive protein (CRP), and cytokines were obtained 0-240 h (h) after SAH. Definition of severe clinical condition was Hunt&Hess (H&H) 3-5 and less severe clinical condition H&H 1-2. Impaired cerebral circulation was assessed by clinical examination, transcranial doppler, CT-scan, and angiography. Glasgow outcome scale (GOS) evaluated the outcome. Compared to admission, 0-48 h after SAH, the following was observed 49-240 h after SAH; (a) ADMA was significantly increased at 97-240 h (highest 217-240 h), (b) CRP was significantly increased at 49-240 h (highest 73-96 h), (c) interleukin-6 (IL-6) was significantly lower at 97-240 h (highest 49-96 h), p < 0.05. ADMA, CRP, and IL-6 were significantly lower and peak arginine/ADMA ratio was significantly higher in patients with H&H 1-2 compared to patients with H&H 3-5, p < 0.05. The peak ADMA or the nadir arginine/ADMA ratio did not differ significantly between patients with (55%) or without (45%) signs of impaired cerebral circulation. The peak ADMA or the nadir arginine/ADMA ratio did not differ significantly between patients with GOS 1-3 and patients with GOS 4-5. ADMA increased significantly after SAH, and the increase in ADMA started after the pro-inflammatory markers (CRP and IL-6) had peaked. This might indicate that endothelial dysfunction, with ADMA as a marker, is induced by a systemic inflammation.