Clinical Assessment of Early Morning Blood Pressure in Patients With Hypertension

Abstract

In most individuals with hypertension, blood pressure (BP) shows a moderate to marked increase around the time of awakening, which has been linked to increases in cardiovascular complications occurring at this time of day. Many antihypertensive agents do not adequately control early morning BP, particularly when administered once daily in the morning. Points to consider in selecting an effective antihypertensive drug include pharmacokinetics and formulation of the agent and timing of administration. Agents with long pharmacologic half-lives, such as the angiotensin II receptor blocker telmisartan, the calcium antagonist amlodipine, and the beta-blocker bisoprolol, are examples of antihypertensive drugs with demonstrated efficacy in controlling early morning BP. Bedtime administration of chronotherapeutic preparations is also effective for controlling early morning BP. Given the association between early morning BP and cardiovascular risk, future clinical trials should focus on the efficacy of antihypertensive drugs during this important period of risk.

Effects of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers on Prothrombotic Processes and Myocardial Infarction Risk

“…Raised dawn and early morning blood pressure is one of the most significant acute risk factors that places a greater hemodynamic burden on the coronary circulation and is associated with the activation of several neurohumoral systems [13]. The morning surge in blood pressure represents the greatest danger, primarily for ‘non-dipper’ or ‘extreme dipper’ patients; in the former this is due to the pressure load that begins relatively early, at dawn, and lasts for 8–10 h, the latter because of the dangerously steep increase in blood pressure [21]. The flow-mediated vasodilatation (FMD) that reflects the functional state of the vessels shows no fluctuation in a healthy population, whereas it fluctuates together with ischemic episodes and is worse in the early morning period in patients with CHD and angina.…”

Influences of the circadian clock on neuronal susceptibility to excitotoxicity

“…Ramifications of these circadian events extend to factors that govern the onset, maintenance and progression of cardiovascular dysfunction including stroke (Uen et al, 2009). Observational studies and a recent meta-analysis have shown that stroke and cardiac arrest occur predominantly in the morning (Hassler and Burnier, 2005; White, 2007; Patel et al, 2008; Uen et al, 2009), thus demonstrating that just as the physiological aspect of the cardiovascular system is governed by a circadian overlord, so is its dysfunctional state governed by a time-of-day variation.…”

“…Basic science and clinical research have repeatedly revealed that stroke, among other cardiovascular events such as myocardial infarction, sudden cardiac death and arrhythmias, has a propensity to precipitate at a particular time-of-day; wherein these events are most likely to occur during the hours of 6:00 a.m. and 12:00 p.m. (Hassler and Burnier, 2005; Manfredini et al, 2005; White, 2007; Patel et al, 2008; Uen et al, 2009). Not only is the incidence of an ischemic event (such as acute myocardial infarction) higher during the morning hours, but the mortality resulting from such an event was also higher during this time (Manfredini et al, 2004).…”

“…Although causative data to evaluate mechanisms underlying these diurnal variations are lacking, circadian rhythms in activity, blood pressure, platelet aggregatability, cortisol and catecholamines are candidate factors (Bridges and Woods, 2001; Hassler and Burnier, 2005; White, 2007; Patel et al, 2008; Uen et al, 2009). These factors contribute to greater blood coagulability during the early morning hours, rendering the subject more susceptible to the adverse effects of ischemic events.…”

“…Among all the factors that contribute to a stroke, blood pressure is the one factor which has displayed a very strong correlation to stroke incidence and clinically is the most practical to measure and manipulate. Some studies demonstrated that maintaining blood pressure within normal limits during the peak susceptibility hours (early morning) can reduce adverse cardiovascular events, stroke in particular (White, 2007; Patel et al, 2008). On the other hand, some other researchers alleged that it was the night-time blood pressure that predicated the risk of an individual toward a stroke (Uen et al, 2009; Yano and Kario, 2012a,b).…”