Abstract 156: Glyceryl Trinitrate for Hyperacute Stroke: Results from the Efficacy of Nitric Oxide in Stroke (ENOS) Trial

Abstract

Background: High blood pressure (BP) is common during the acute phase of stroke and is associated with a poor outcome. Administration of glyceryl trinitrate (GTN), a nitric oxide donor that lowers BP, improved functional outcome in the small ambulance-based paramedic-delivered RIGHT trial. Methods: ENOS was an international prospective randomised single-blind blinded-endpoint trial. Patients with acute (<48 hours) stroke and systolic BP 140-220 mmHg were randomised to GTN (5 mg transdermal) or no GTN. Outcomes included shift in modified Rankin Scale (mRS, primary), Barthel Index (BI) and death at 3 months. Analyses are by regression (binary, ordinal or multiple) with adjustment for baseline covariates; results are odds ratio (OR)/mean difference (MD) with 95% confidence intervals (95% CI). Results: Of 4,011 enrolled patients, 273 were randomised (GTN 144, no GTN 129) within 6 hours of onset of stroke: age 70 (SD 13); BP 167 (18)/91 (13) mmHg; Scandinavian Stroke Scale 32 (12); ischaemic 76%, ICH 22%; stroke-randomisation 4.6 hours. Treatment with GTN was associated with improved mRS (OR 0.51, 95% CI 0.32-0.80), BI (MD 13.5, 95% CI 4.6 to 22.5), and reduced death (OR 0.31, 95% CI 0.11-0.91). Significant improvements in mood, quality of life and cognition were also seen. Summary: In the subgroup of patients randomised within 6 hours of stroke onset, treatment with GTN was associated with less dependency, disability and death. These positive results mirror those seen in the RIGHT pilot trial.