Jan 6 2014
By Eleanor McDermid, Senior medwireNews Reporter
Intensive antihypertensive treatment to a systolic blood pressure (SBP) target of 130 mmHg is equally beneficial for patients with and without established cardiovascular disease (CVD), research suggests.
Paolo Verdecchia (Hospital of Assisi, Italy) and co-workers conducted a post-hoc analysis of a clinical trial (Cardio-Sis) that randomly assigned 1111 patients with hypertension to receive treatment to a SBP target of 130 or 140 mmHg.
For their analysis, Verdecchia et al divided patients into those who did and did not have established CVD at study entry (n=216 and 895, respectively). They found that, over 2 years, the trial’s primary endpoint of the prevalence of left ventricular (LV) hypertrophy fell significantly more in patients treated to the tighter SBP target of 130 mmHg, irrespective of whether they had established CVD.
Tight BP control resulted in a 40% reduction in LV hypertrophy relative to standard control, after accounting for age and LV hypertrophy prevalence at baseline, and there was no significant interaction with CVD status.
The team says that “the advantage of a tight over a standard BP control was found at any level of achieved systolic BP, without any paradoxical rise in the risk of events at low levels of achieved BP during follow-up.”
Some previous analyses have suggested a J-shaped relationship between SBP and cardiovascular events, with an increase in events at the very lowest achieved levels of SBP. But this did not occur in Cardio-Sis; instead, there was a steady rise in the rate of cardiovascular events as SBP increased.
A similar proportion of patients with and without CVD achieved SBP below 130 mmHg, at 52.9% and 53.8%, respectively, in the tight control group, and 35.1% and 33.0%, respectively, in the standard control group. Although considerably more patients with than without CVD died or had a cardiovascular event during follow-up, at 16.7 versus 4.8 per 100 patients/year, the rate among those with CVD was significantly lower with tight than standard BP control, at 7.9 versus 11.2 per 100 patients/year.
“Our results support the hypothesis, derived from previous studies, that the poorer outcome in patients with low values of achieved BP is explained more likely by poor health conditions and frailty associated with concomitant disorders rather than an adverse specific effect of BP reduction caused by treatment,” conclude the researchers in Hypertension.
Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.