Dr. Page is an associate professor of clinical pharmacy and physical medicine and a clinical specialist, Division of Cardiology, University of Colorado Health Sciences Center, Schools of Pharmacy and Medicine.
As with most biologic processes,blood pressure (BP) demonstratesa distinct circadianrhythm, characterized by a substantialreduction during sleep (the nocturnaldip) followed by a moderate to markedincrease around the time of awakening(the morning surge). It is not surprisingthat the onset of acute cardiovascular (CV)events (eg, myocardial infarction, suddencardiac death, and stroke) also showsa circadian pattern, with peak occurrenceduring the early morning hours.1,2In patients with hypertension, this surgein BP (eg, above 135/85 mm Hg) duringthe first 2 hours after waking, but not inthe evening (the last 2 hours before goingto bed) has been defined as morninghypertension.3 This morning BP surge haspathological significance as it is positivelyrelated to degree of target-organ damage,such as carotid intima-media thicknessand left ventricular hypertrophy.4-6 Themagnitude of the morning surge also is anindependent predictor of cerebrovascularand cardiac events.7
Nondippers Versus Extreme Dippers
Two types of morning hypertension exist.8-10The patients who demonstrate a nocturnaldecrease in BP that is <10% of theirdaytime BP are known as nondippers. Theother type of patients are the extreme dipperswho exhibit a 20% or more decreasein nocturnal BP, compared with daytimeBP. Finally, a patient can be an inverteddipper/riser in which their BP does notdecrease or actually may increase at night.Nondippers and risers typically do notshow a surge in BP on awakening but usuallyhave sustained early morning hypertension.An excessive morning surge iscommon in extreme dippers.8-10
What Causes Morning Hypertension?
The morning surge in BP is influenced bymany pathophysiological factors, such asactivity of the autonomic and renin-angiotensin-aldosterone systems and dietarysodium intake. Other alterations thatoccur during the early morning that canhave a significant impact on increasing CVrisk in this population include increasedheart rate, vascular tone, blood viscosity,and platelet aggregability. With the adventof ambulatory blood pressure monitoring(ABPM), this technology has improvedidentification of patients with excessivemorning surges and has facilitated assessmentof antihypertensive agents that maybe particularly effective in this subgroupof the hypertensive population.11,12
In the Japan Morning Surge-1 study,Ishikawa and colleagues used ABPM in611 patients with morning hypertensionto determine important patient-specificcharacteristics.13 The analysis showedthat patients with morning hypertensionare more likely to be of older age, as wellas have a longer duration of hypertensionand antihypertensive medication use, displaya higher prevalence of left ventricularhypertrophy with an elevated B-type natriureticpeptide concentration, and exhibit alower glomerular filtration rate.
As for pharmacotherapy, choice of anagent is dependent upon the pharmacokineticsand formulation of the drug,published evidence, and timing of administration.Medications with long half-lives,such as telmisartan, amlodipine, chlorthalidone,and bisoprolol, have demonstratedefficacy in controlling early morning BP.Bedtime administration of chronotherapeuticpreparations as well as alphablockerssuch as doxazosin have alsobeen effective, particularly when used incombination with ABPM.14-24
This communication on the importance of home blood pressure monitoring is supported by Omron Healthcare, Inc. It is intended to help pharmacists and their staff understand the importance of home blood pressure monitoring.
- Cohen MC, Rohtla KM, Lavery CE, Muller JE, Mittleman MA. Meta-analysis of the morning excess of acute myocardial infarction and sudden cardiac death. Am J Cardiol. 1997;79(11):1512-1516.
- Muller JE, Ludmer PL, Willich SN, et al. Circadian variation in the frequency of sudden cardiac death. Circulation. 1987;75(1):131-138.
- Pickering TG. Morning hypertension. J Clin Hypertens (Greenwich). 2007;9(3):224-228.
- Giles TD. Circadian rhythm of blood pressure and the relation to cardiovascular events. J Hypertens Suppl. 2006;24(2):S11-16.
- Pol?nia J, Amado P, Barbosa L, et al. Morning rise, morning surge and daytime variability of blood pressure and cardiovascular target organ damage. A cross-sectional study in 743 subjects. Rev Port Cardiol. 2005;24(1):65-78.
- Marfella R, Siniscalchi M, Nappo F, et al. Regression of carotid atherosclerosis by control of morning blood pressure peak in newly diagnosed hypertensive patients. Am J Hypertens. 2005;18(3):308-318.
- Kario K, Ishikawa J, Pickering TG, et al. Morning hypertension: the strongest independent risk factor for stroke in elderly hypertensive patients. Hypertens Res. 2006;29(8):581-587.
- Ohkubo T, Imai Y, Tsuji I, et al. Relation between nocturnal decline in blood pressure and mortality. The Ohasama Study. Am J Hypertens. 1997;10(11):1201-1207.
- White WB. Clinical assessment of early morning blood pressure in patients with hypertension. Prev Cardiol. 2007;10(4):210-214.
- Kario K, Shimada K. Risers and extreme-dippers of nocturnal blood pressure in hypertension: antihypertensive strategy for nocturnal blood pressure. Clin Exp Hypertens. 2004;26(2):177-189.
- Sica DA. What are the influences of salt, potassium, the sympathetic nervous system, and the renin-angiotensin system on the circadian variation in blood pressure? Blood Press Monit. 1999;4(Suppl 2):S9-S16.
- Pickering TG, Miller NH, Ogedegbe G, et al. Call to action on use and reimbursement for home blood pressure monitoring: executive summary: a joint scientific statement from the American Heart Association, American Society Of Hypertension, and Preventive Cardiovascular Nurses Association. Hypertension. 2008;52(1):1-9.
- Ishikawa J, Hoshide S, Shibasaki S, et al. Relationship between morning hypertension identified by home blood pressure monitoring and brain natriuretic peptide and estimated glomerular filtration rate: the Japan Morning Surge 1 (JMS-1) Study. J Clin Hypertens (Greenwich). 2008;10(1):34-42.
- Mengden T, Battig B, Schubert M, et al. Comparison of casual, ambulatory and self-measured blood pressure in a study of nitrendipine vs bisoprolol. Eur J Clin Pharmacol. 1992;42(6):569-575.
- White WB, Sica DA, Calhoun D, Mansoor GA, Anders RJ. Preventing increases in early-morning blood pressure, heart rate, and the rate-pressure product with controlled onset extended release verapamil at bedtime versus enalapril, losartan, and placebo on arising. Am Heart J. 2002;144(4):657-665.
- Glasser SP, Neutel JM, Gana TJ, Albert KS. Efficacy and safety of a once daily graded-release diltiazem formulation in essential hypertension. Am J Hypertens. 2003;16(1):51-58.
- Eguchi K, Kario K, Hoshide Y, et al. Comparison of valsartan and amlodipine on ambulatory and morning blood pressure in hypertensive patients. Am J Hypertens. 2004;17(2):112-117.
- White WB, Lacourciere Y, Davidai G. Effects of the angiotensin II receptor blockers telmisartan versus valsartan on the circadian variation of blood pressure: impact on the early morning period. Am J Hypertens. 2004;17(4):347-353.
- White WB, Lacourciere Y, Gana T, et al. Effects of graded-release diltiazem versus ramipril, dosed at bedtime, on early morning blood pressure, heart rate, and the rate-pressure product. Am Heart J. 2004;148(4):628-634.
- Kamoi K, Ikarashi T. The bedtime administration of doxazosin controls morning hypertension and albuminuria in patients with type-2 diabetes: evaluation using home-based blood pressure measurements. Clin Exp Hypertens. 2005;27(4):369-376.
- Lacourciere Y, Neutel JM, Davidai G, Koval S. A multicenter, 14-week study of telmisartan and ramipril in patients with mild-to-moderate hypertension using ambulatory blood pressure monitoring. Am J Hypertens. 2006;19(1):104-112.
- Williams B, Gosse P, Lowe L, Harper R; PRISMA I Study Group. The prospective, randomized investigation of the safety and efficacy of telmisartan versus ramipril using ambulatory blood pressure monitoring (PRISMA I). J Hypertens. 2006;24(1):193-200.
- Gosse P, Neutel JM, Schumacher H, et al. The effect of telmisartan and ramipril on early morning blood pressure surge: a pooled analysis of two randomized clinical trials. Blood Press Monit. 2007;12(3):141-147.
- Wright JT, Jr, Harris-Haywood S, Pressel S, et al. Clinical outcomes by race in hypertensive patients with and without the metabolic syndrome: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Arch Intern Med. 2008;168(2):207-217.