Better than expected survival after primary intracerebral hemorrhage in patients with untreated hypertension despite high admission blood pressures

Abstract

Hypertension is the most important modifiable risk factor for primary intracerebral hemorrhage (ICH), but little is known of the effect of preceding hypertension on outcome. Because high mean arterial blood pressure (MABP) at admission is an independent predictor of early death in patients with ICH, we explored its role on survival and poor outcome separately in normotensive subjects and subjects with treated and untreated hypertension. We assessed clinical data and the 3-month outcome of patients with spontaneous ICH (n = 453) admitted to the stroke unit of Oulu University Hospital between 1993 and 2004. Standard medical treatment was used to lower MABP from levels >127 mmHg to <120 mmHg. Overall mortality within 3 months was 28%. Patients with untreated hypertension had significantly lower mortality (6%) than those with treated hypertension (36%, P < 0.001) or those without hypertension (25%, P < 0.01). High admission MABP associated with early death in normotensive subjects (P < 0.05) and those on medication for hypertension (P < 0.01) but not in those with untreated hypertension. Patients with untreated hypertension were younger and had less frequently cardiac disease, diabetes, and/or warfarin or aspirin medications, but they showed the highest blood pressures (BPs) at admission. Amongst patients with high admission MABP, favorable outcome was seen most frequently in those who had untreated hypertension. Hematoma growth did not associate with high MABP amongst them. Despite their higher BP values at admission, subjects with untreated hypertension showed better survival and more frequently favorable outcome after BP-lowering therapy than other patients.