Morning blood pressure surge and the risk of stroke.

Abstract

HomeCirculationVol. 108, No. 15Morning Blood Pressure Surge and the Risk of Stroke Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBMorning Blood Pressure Surge and the Risk of Stroke Michael Bursztyn, MD Michael BursztynMichael Bursztyn Department of Medicine, Hadassah Mount Scopus, Jerusalem, Israel Search for more papers by this author Originally published14 Oct 2003https://doi.org/10.1161/01.CIR.0000093726.33033.3FCirculation. 2003;108:e110–e111To the Editor:I read with great interest the important study of Kario et al1 in the March 18th issue about morning blood pressure surge and the risk of stroke. I would like to point out that the blood pressure surge does not occur solely on awakening in the morning. My colleagues and I2 as well as others3 have found that blood pressure surges also occur after the afternoon nap, also known as the siesta. As noted in the accompanying editorial, we have also described that practice of the siesta may be associated with doubled mortality in the elderly.4 More recently, two independent groups in Greece have found people in whom the siesta is prevalent and in whom a second peak of stroke corresponds to awakening from the siesta.3,5 The unaccounted-for siesta may be one cause of misclassification of dipping; another is nocturnal awakening, the siesta’s nocturnal mirror. Many older individuals such as the cohort of Kario et al,1 wake up at night, sometimes several times (especially men with prostatism). If their nocturnal awake blood pressure measurements were included in the nocturnal average, as occurs when such awakenings are not accounted for, major misclassification would occur.6 Such misclassification would bias the night’s blood pressure, lack of dipping (or extreme dipping), and the subsequent blood pressure surge on awakening. As this surge may be extremely important as pointed out by Kario et al,1 it should be appropriately evaluated. Until more precise tools are widely available, estimation by using patients’ diaries is a simple, easy, inexpensive, and universally available tool for such evaluation. Last but not least, it is well accepted by patients and increases their confidence in the analysis extracted from the little box.1 Kario K, Pickering TG, Umeda Y, et al. Morning surge in blood pressure as a predictor of silent and clinical cerebrovascular disease in elderly hypertensives. Circulation. 2003; 107: 1401–1406.LinkGoogle Scholar2 Bursztyn M, Mekler J, Ben-Ishay D. The siesta and ambulatory blood pressure monitoring: is waking up the same in the morning and afternoon? J Hum Hypertens. 1996; 10: 287–292.MedlineGoogle Scholar3 Stergiou GS, Vemmos KN, Pliachopoulou KM, et al. Parallel morning and evening surge in stroke onset, blood pressure, and physical activity. Stroke. 2002; 33: 1480–1486.LinkGoogle Scholar4 Bursztyn M, Ginsberg G, Rozenberg-Hammerman R, et al. The siesta in the elderly: risk factor for mortality? Arch Int Med. 1999; 159: 1582–1586.CrossrefMedlineGoogle Scholar5 Spengos K, Vemmos KN, Tsivgoulis G, et al. Two-peak temporal distribution of stroke onset in Greek patients: a hospital-based study. Cerebrovasc Dis. 2003; 15: 70–77.CrossrefMedlineGoogle Scholar6 Perk G, Ben-Arie L, Mekler J, et al. Nocturnal urination may determine dipping status. Hypertension. 2001; 37: 749–752.CrossrefMedlineGoogle ScholarcirculationahaCirculationCirculationCirculation0009-73221524-4539Lippincott Williams & WilkinscirculationahaCirculationCirculationCirculation0009-73221524-4539Lippincott Williams & WilkinscirculationahaCirculationCirculationCirculation0009-73221524-4539Lippincott Williams & WilkinsMengden Thomas, , MD, Uen Sakir, , MD, and Vetter Hans, , MD14102003Marfella Raffaele, , MD, PhD, Esposito Katherine, , MD, PhD, Gualdiero Pasquale, , MD. PhD, and Guigliano Dario, , MD, PhD14102003ResponseKario K., , MD, Umeda Y., , MD, Hoshide S., , MD, Hoshide Y., , MD, Morinari M., , MD, Murata M., , MD, Kuroda T., , MD, Shimada K., , MD, Pickering T.G., , MD, and Schwartz J.E., , PhD14102003To the Editor:We read with interest the report on morning surge of blood pressure by Kario et al1 and the editorial by Kaplan.2 For the recognition of the morning surge, the use of early morning home blood pressure measured by the patient him- or herself is suggested.2 From our own experience of ambulatory 24-hour monitoring (ABPM) and home blood pressure monitoring,3 we agree with the potential benefits of this approach.We compared self-measured blood pressure and heart rate values with the respective values of ABPM in a group of 37 consecutively recruited hypertensives with poor blood pressure control despite antihypertensive medication (Mengden et al, unpublished data, 2000). Self-measurement of blood pressure was performed with the highly accurate Omron IC system (upper arm, oscillometric device). Patients were instructed to measure blood pressure after rising and before taking antihypertensive medication for a period of 2 weeks. As the Omron IC is a memory device with automatic storage of blood pressure/heart rate values together with the respective time of measurement, we were able to compare the trough values of self-measured home blood pressure with the respective trough values of ABPM (Spacelabs Medical 90207 recorder). We compared self-measurement (in the morning before intake of antihypertensive medication), the average of 3 ABPM recordings at the end of the dose interval (morning ABPM, trough value before intake of antihypertensive medication, measuring cycles 15 minutes), and the mean daytime readings of ABPM (6 am to 10 pm).The highest blood pressure values were observed with self-measurement of home blood pressure (163.0±20.0/90.2±10.1 mm Hg) as compared with morning ABPM values (151.1±20.1/88.0±10.9 mm Hg; P=0.0001 for systolic values). ABPM daytime values (148.4±14.9/89.0±9.4 mm Hg) did not differ significantly from morning ABPM values. Heart rate at the end of the dose interval was significantly lower for self-measurement as compared with ABPM readings (71.8±9.0 versus 76.9±14.6 and 77.2±12.0; P=0.01). In our patients, self-measurement delivered additional information about the early morning rise of blood pressure and heart rate that was different as compared with ABPM. The self-measured readings indicate the need for more effective, long-acting antihypertensive therapy (24-hour or longer efficacy). The significantly lower heart rate observed with self-measurement despite higher blood pressure values may indicate that activation of the sympathetic nervous system played a minor role in the morning surge.Home measurements can be used to recognize the morning surge of blood pressure. Given the well-known observer bias for the reporting of self-measured values, memory-equipped devices should be used to identify the exact measurement time with regard to rising and medication intake.4To the Editor:Kario et al1 report that a higher morning blood pressure surge (MBPS) is associated with stroke risk independent of ambulatory blood pressure (BP), nocturnal BP falls, and silent infarct in older hypertensives. The authors suppose that an excessive MBPS might trigger strokes through some hemodynamic mechanism such as increased shear stress on the atherosclerotic cerebral vessels, but there are several other factors that change during the morning hours. These include an increase of sympathetic nervous activity, particularly α-adrenergic activity,2 and other related acute risk factors such as platelet hyperactivity, hypercoagulability and hypofibrinolysis, blood viscosity, and increased vascular spasm.3 We have recently reported4 that in never-treated subjects with essential hypertension, a rise in systolic BP ≥50 mm Hg and/or diastolic BP ≥22 mm Hg during the early morning (6:00 to 10:00 am) is associated with the highest morning values of the ratio between low-frequency and high-frequency RR interval (considered as a marker of sympathetic overactivity), increased urinary catecholamine output, and left ventricular hypertrophy. The coexistence of sympathetic overactivity and left ventricular hypertrophy in patients with higher MBPS might contribute to their raised vascular risk and might explain the increase of cardiovascular accidents in early morning. The increase of sympathetic activity in the early morning is associated with some adverse modifications regarding heart rate, fibrinolytic activity, and platelet aggregability5 that may make the morning BP rise at most a pathophysiological cofactor in the determination of the increased morning rate of cardiovascular morbidity and fatal events.Dr Burszytyn pointed out that individual behavioral factors such as a siesta and nocturnal awaking are important modulators of the association between morning blood pressure (BP) surge and cardiovascular risk. Recently developed ambulatory BP monitors (ABPM) equipped with actigraphy1 could be used to assess the relationships between the morning- or siesta-associated BP surges and changes in physical activity.Dr Mengden et al recommended using memory-equipped devices for self-measurement of morning BP (SMBP) to reduce observer bias and to demonstrate the marked differences between morning BP and pulse rate measured by SMBP and ABPM. They found that morning systolic BP was 12 mm Hg higher by SMBP than by ABPM, whereas morning pulse rate was 5 mm Hg lower by SMBP. This may indicate that self-monitoring per se might be stressful for some patients. In our Jichi Morning-Hypertension Research (J-MORE) Pilot Study of a total of 1027 consecutive hypertensives who were taking the same antihypertensive medication for at least 3 months, SMBP was conducted twice in the morning just before taking antihypertensive medication and in the evening just before going to bed for 3 consecutive days, using automatic devices. In this study, the first BP reading of each pair of the 6 sets of measurements (morning and evening for 3 days) was consistently higher by 3.4 to 3.9 mm Hg systolic and by 1.1 to 1.7 mm Hg diastolic, whereas the difference between the first and the second pulse rates was <1.0 bpm. This suggests that some pressor response occurs during the first measurement of SMBP. To reduce the effects of this response, the second measurement may be preferable to assess morning BPs.SMBP cannot directly assess the morning BP surge, but when evening BPs measured just before going to bed are combined with morning BPs, some additional information can be derived for clinical practice. When we analyzed data from the same 519 patients2 using the morning and evening BPs (ME) derived from the ABPM data, after controlling for baseline characteristics, both the ME average (morning systolic BP+evening systolic BP÷2) (10 mm Hg increase; relative risk=1.41 [95% CI=1.19 to 1.67], P=0.0001) and the ME surge (morning systolic BP−evening systolic BP) (10 mm Hg increase; relative risk=1.24 (95% CI=1.08 to 1.42], P=0.0025) were independently associated with the risk of stroke.We agree with the opinion of Dr Marfella et al that other sympathetic activation–associated potentiation of risk factors, including heart rate and platelet/hemostatic factors,3 would augment the morning risk for cardiovascular events. In fact, in our recent study, the morning increase in platelet aggregation and in the plasma levels of von Willebrand factor and tissue-type plasminogen activator, 2 in vivo markers of endothelial cell stimulation, were significantly correlated with a higher morning BP surge in hypertensive patients (K. Kario MD, et al, Linkage between morning surge in blood pressure and acute risk factors for silent cerebrovascular disease in elderly hypertension, submitted for publication). To clarify the impact of morning BP surge from other confounders, we have just initiated the Japan Morning Surge-1 (JMS-1) Study, a randomized parallel control study, in which we attempt to study the effect of suppression of morning BP surge on target organ damage in treated hypertensives with high morning BPs.We believe that the strict control of morning BP as well as morning-potentiated risk factors would achieve more effective prevention of cardiovascular events in hypertensive patients. Previous Back to top Next FiguresReferencesRelatedDetailsCited By Sabater-Hernández D, Fikri-Benbrahim O and Faus M (2010) Utilidad de la monitorización ambulatoria de la presión arterial en la toma de decisiones clínicas, Medicina Clínica, 10.1016/j.medcli.2009.07.019, 135:1, (23-29), Online publication date: 1-Jun-2010. Brotman D, Golden S and Wittstein I (2007) The cardiovascular toll of stress, The Lancet, 10.1016/S0140-6736(07)61305-1, 370:9592, (1089-1100), Online publication date: 1-Sep-2007. KARIO K (2005) “Cocktail” Antihypertensive Chronotherapy for Perfect Control of Morning Hypertension in Diabetic Patients, Internal Medicine, 10.2169/internalmedicine.44.1211, 44:12, (1211-1212), . October 14, 2003Vol 108, Issue 15 Advertisement Article InformationMetrics https://doi.org/10.1161/01.CIR.0000093726.33033.3FPMID: 14557349 Originally publishedOctober 14, 2003 PDF download Advertisement