Post-stroke diastolic blood pressure and risk of recurrent vascular events.

Abstract

Recent clinical trials and expert consensus guidelines have typically focused on the issue of systolic blood pressure (SBP) targets for reducing vascular risk. However, little is known about the relationship of the diastolic BP (DBP) level with vascular outcomes after a stroke. A multicenter trial dataset involving 3680 recent (<4 months) non-cardioembolic stroke patients followed for 2 years was analyzed. Subjects were categorized per mean DBP level (mmHg) during follow-up: low-normal (<70), normal (70 to <80), high-normal (80-89) and high (≥90). Pulse pressure (PP) was prespecified by three categories of <60, 60 to <70, and ≥70 mmHg. Independent associations of mean DBP level with major vascular events (MVEs) and ischaemic stroke were assessed. Major vascular events occurred in 20.7% of the low-normal, 15.1% of the normal, 16.9% of the high-normal and 19.2% of the high DBP groups, whilst stroke occurred in 9.9%, 6.8%, 8.5% and 10.8%, respectively. Compared with the normal DBP group, risk of MVEs was higher in the low-normal DBP group (adjusted hazard ratio 1.33; 95% confidence interval 1.04-1.71). Amongst those with SBP 120 to <140 mmHg, risk of MVEs (1.89; 1.13-3.15) and stroke (2.87; 1.48-5.53) was higher in subjects with PP ≥70 (mean DBP 62.4 ± 3.8) than those with the lowest PP (mean DBP 78.0 ± 5.9) whilst, amongst those with SBP <120 mmHg, PP 60 to <70 (mean DBP 52.7 ± 2.5) was associated with increased risk of stroke (5.85; 1.25-27.5). Diastolic BP levels in the low-normal range, particularly accompanied by an increased PP of >60, confer increased risk of MVEs and stroke amongst patients after recent non-cardioembolic stroke.