Temporal profiles of blood pressure, circulating nitric oxide, and adrenomedullin as predictors of clinical outcome in acute ischemic stroke patients

Stroke remains an important health and social challenge. The present study investigated whether blood pressure (BP) parameters and circulating levels of nitric oxide metabolites (NOx) and adrenomedullin (AM) may predict clinical outcomes of stroke. Patients (n=76) diagnosed with acute ischemic stroke were admitted to the stroke unit and clinical history data and monitored parameters were recorded. Blood plasma was collected at days 1, 2, and 7 to measure NOx and AM levels. Infarct volume, neurological severity [on the National Institutes of Health Stroke Scale (NIHSS)], and functional prognosis (on the Rankin scale) were measured as clinical outcomes. Patients with higher BP had more severe symptoms (NIHSS >3; P<0.01) and BP variability predicted neurological severity and growth of infarct volume. NOx values were significantly lower in stroke patients than in healthy controls (P<0.01). An increase in NOx levels from day 1 to day 2 was beneficial for the patients as measured by NIHSS at 7 days and 3 months, and by Rankin at 3 months [odds ratio (OR), 0.91] whereas a steep increase from day 2 to day 7 was detrimental and associated with an increase in infarct volume (OR, 35.3). AM levels were significantly higher in patients at day 1 and 2 than in healthy individuals (P<0.01) and these levels returned to normal at day 7. Patients with high AM levels at day 2 had significantly higher NIHSS scores measured at day 1 (P<0.05) and 7 (P<0.01). A receiving operating characteristic curve analysis identified that AM levels at day 2 of >522.13 pg/ml predicted increased neurological severity at day 7 (area under the curve=0.721). Multivariate logistic regression indicated that AM levels at day 2 predicted increased neurological severity at 7 days and at 3 months. BP parameters and changing levels for NOx and AM predicted long-term clinical outcomes as measured by infarct volume, neurological severity scale, and functional prognosis.