Predictor Of Target Organ Damage Research Articles

GW29-e1878 Left ventricular structure and function in relation to peripheral and central blood pressure in a general population

Central blood pressure (BP) is a predictor of target organ damage. No previous population study addressed the question to what extent central compared with peripheral is related to left ventricular (LV) structure and function. In 577 Flemish recruited from the general population (47.8% women; mean

A0329 Left ventricular structure and function in relation to peripheral and central blood pressure in a general population

Objectives: Central blood pressure (BP) is a predictor of target organ damage. No previous population study addressed the question to what extent central compared with peripheral is related to left ventricu-lar (LV) structure and function. Methods: In 577 Flemish recruited from the general population (47.8% women; mean age 50.5 years), we assessed the multivariable-adjusted associations of echocardiographic LV structure and systolic and diastolic LV function (Vivid7 Pro device; EchoPac software, version 4.0.4; GE Vingmed, Horten, Norway) with peripheral and central pressure, as recorded by radial applanation tonometry (SphygmoCor software, version 9.0). Association sizes were expressed per 1-SD increment in peripheral or central systolic/diastolic BP. Results: Peripheral compared with central systolic BP was 10.2 mm Hg higher (P < 0.0001), whereas dias-tolic BP was similar peripherally and centrally (P = 0.50). Associations were closer (P ≤ 0.020) with central than peripheral systolic BP for LV mass (+0.886 g/m2) and left atrial volume (+0.166 ml/m2) indexed to body surface area, peak A transmitral flow (+0.343 cm/s), peak e′ mitral annular movement (–0.219 cm/s) and the E/A ratio (–0.021). Associations were closer (P ≤ 0.038) with central than peripheral diastolic BP for left atrial volume index (+0.267 ml/m2), e′ (–0.104 cm/s) and E/e′ (+0.081). Ejection fraction and global longitudinal strain were similarly associated with central and peripheral systolic (P ≥ 0.62) and diastolic (P ≥ 0.18) BP. Conclusion: In asymptomatic people recruited from the general population, LV mass and atrial volume indexes and selected haemodynamic measurements reflecting diastolic LV function are slightly but significantly closer associated with central than peripheral BP.

Office blood pressure measurement in the 21st century.

Measurement of blood pressure (BP) using the auscultatory method must follow specific rules and conditions to be reliable. Nonetheless, these requirements are often not followed in clinical practice, resulting in inaccurate BP readings. Simply replacing manual sphygmomanometers with an oscillometric device may still produce readings that are associated with a white coat effect. These limitations can be overcome by using an oscillometric sphygmomanometer that automatically records multiple readings with the patient resting quietly and alone, called automated office (AO)BP. AOBP produces office readings with a reduced white coat effect, which are also similar to the awake ambulatory BP. There is also evidence that AOBP is a better predictor of target organ damage than attended office BP. Furthermore, clinical outcome data support AOBP as having both a similar diagnostic threshold as awake ambulatory BP and a lower treatment target. Using AOBP in clinical practice simplifies recording office BP by not requiring an additional period of rest before activation of the device and by not having staff present during the actual measurements. Recent studies have reported that automatic BP measurements taken by staff in research studies with close adherence to guidelines using AOBP devices may produce similar readings to AOBP. Further research is needed to determine the best method for recording BP at systolic targets <130mm Hg and the relationship of office BP to ambulatory BP and home BP.

Relationship between blood pressure variability and target organ damage in elderly patients.

To investigate the relationship between 24 h systolic blood pressure variability (SBPV) and target organ damage in elderly patients with essential hypertension. 180 elderly patients (≥ 80 y) with hypertension admitted to our hospital from January 2015 to January 2017 were selected as hypertension group and divided into high blood pressure variability (BPV) group and low BPV group according to the 50th percentile (P50) of 24 h SBPV, while 90 elderly non-hypertension patients admitted during the same period were enrolled as control group. 24 h ambulatory blood pressure values of patients in the three groups were recorded. The total cholesterol (TC), left ventricular mass index (LVMI), carotid artery intima-media thickness (IMT), 24 h microalbuminuria (MA) and complications with cardiovascular disease in patients of the three groups were compared and analyzed. Logistic analysis was conducted with MA, IMT and LVMI as the dependent variables and the remaining risk factors as the independent variables. 24 h SBPV and daytime SBPV (d SBPV) in patients of the hypertension group were significantly higher than those in the control group (p < 0.01); the incidences of coronary heart disease and atherosclerotic plaque as well as IMT, LVMI and MA were higher in the high BPV group than those in the low BPV group (p < 0.05 or p < 0.01). The multivariate results showed that 24 h SBPV was associated with IMT, LVMI and MA. BPV can serve as an important indicator to predict target organ damage in elderly patients with essential hypertension. 24 h SBPV can reflect the degree of target organ damage in elderly hypertensive patients.

Abstract 044: Sex Differences in Relative Contributions of Hemodynamic Parameters to Blood Pressure: A Population-based Study of Adolescents and Middle-aged Adults

Hypertension is a leading cause of death. Sex differences in blood pressure (BP) and hypertension prevalence emerge during adolescence and remain throughout reproductive age. Sex differences in BP-underlying hemodynamics, i.e., in the relative contributions of stroke volume (SV), total peripheral resistance (TPR) and heart rate (HR) to BP, have not been investigated in these age categories in a population-based setting. We studied a cohort of 1,347 individuals, including 911 adolescents (12-18 years, 52 % female) and 426 young to middle-aged adults (36-65 years, 56 % female). Beat-by-beat systolic BP (SBP) and diastolic BP (DBP), together with HR, SV, and TPR, were measured with a Finometer throughout a 52-min protocol; the protocol was intended to “mimic” daily-life activities, such as changes in posture and mental stress. It is well established that BP during regular daily activities (ambulatory BP monitoring) is a better predictor of target-organ damage than standard office BP. The relative contributions of HR, SV and TPR to SBP and DBP were determined by decomposing the model-explained variance into non-negative contributions. The relative contributions of SV, TPR and HR to SBP and DBP showed marked sex differences in young and middle-aged adults. The main determinant of higher SBP was SV in females (55 [50-60] % in females vs. only 35 [30-40] % in males), whereas it was TPR in males (47 [41-52] % in males vs. only 30 [26-34] % in females). The main determinant of higher DBP was TPR in both sexes, but its contribution was higher in males than females (58 [52-63] % vs. 41 [36-45] %, respectively). These sex differences were seen across most of the 52-min protocol, being most prominent during standing and least evident during mental stress. Similar sex differences were observed in adolescents, but they were less pronounced, being significant only during standing. The present population-based study of adolescents and young to middle-aged adults, suggest that marked sex differences exist in BP-underlying hemodynamics, with BP being driven mainly by SV in females and by TPR in males. These results underscore the need for sex-specific treatments of hypertension (not recommended currently), which affects 3-5 % of adolescents and 23-58% of young to middle-aged adults.

Maximum home blood pressure is a useful indicator of diabetic nephropathy in patients with type 2 diabetes mellitus: KAMOGAWA-HBP study.

Maximum home systolic blood pressure has been shown to predict target organ damage. We aimed to clarify the association between maximum home systolic blood pressure and urine albumin to creatinine ratio, an indicator of early-phase diabetic nephropathy in patients with type 2 diabetes. In 1040 patients, we assessed the relationship of mean or maximum home systolic blood pressure and urine albumin to creatinine ratio, and compared the area under the receiver operating characteristic curve of mean or maximum home systolic blood pressure for diabetic nephropathy (urine albumin to creatinine ratio ⩾30 mg/g Cr). Multivariate linear regression analyses indicated that mean morning systolic blood pressure ( β = 0.010, p < 0.001) and maximum morning systolic blood pressure ( β = 0.008, p < 0.001) were significantly associated with urine albumin to creatinine ratio. Area under the receiver operating characteristic curve (95% confidence interval) for diabetic nephropathy in mean and maximum morning systolic blood pressure was 0.667 (0.634-0.700; p < 0.001) and 0.671 (0.638-0.703; p < 0.001), respectively. Maximum home systolic blood pressure, as well as mean home systolic blood pressure, was significantly associated with diabetic nephropathy in patients with type 2 diabetes.

Interarm blood pressure differences predict target organ damage in type 2 diabetes.

Patients with type 2 diabetes mellitus are at high risk for atherosclerotic disease, and proper blood pressure measurement is mandatory. The authors examined the prevalence of an interarm difference (IAD) in blood pressure and its association with cardiovascular risk factors and organ damage (nephropathy, retinopathy, left ventricular hypertrophy, and vascular damage) in a large diabetic population. A total of 800 consecutive patients with type 2 diabetes mellitus were evaluated with an automated simultaneous bilateral device (men: 422 [52.8%]; mean age: 68.1±12.2years). Diabetic patients with systolic IAD ≥5 and systolic IAD ≥10mm Hg showed an increased risk of having vascular damage (adjusted odds ratios: 1.73 and 2.49, respectively) and higher pulse pressure. IAD is highly prevalent in patients with diabetes, is associated with vascular damage, even for IAD ≥5mm Hg, and should be accurately obtained to avoid underdiagnosis and undertreatment of hypertension.

Ethnic Difference in Proximal Aortic Stiffness: An Observation From the Dallas Heart Study

ObjectivesThis study aims to compare ethnic difference in proximal aortic pulse wave velocity (PWV) and characteristic impedance (Zc). BackgroundIncreased aortic stiffness is an independent predictor of target organ damage, incident hypertension, and all-cause mortality. However, previous studies have not directly assessed proximal aortic function in Blacks, the ethnic population with disproportionately high risk for incident hypertension and target organ complications. MethodsWe evaluated the multiethnic, population-based DHS (Dallas Heart Study) participants (N = 2,544, 54.2% women, 49.7% Black) who underwent cardiac magnetic resonance at 1.5-T. Aortic stiffness and Zc were determined from aortic arch PWV and lumen area measurements. Linear regression was used to evaluate ethnic differences in proximal aortic wall stiffness using aortic arch PWV and Zc as dependent variables with and without adjustment for traditional cardiovascular risk factors. Because cardiac output was significantly higher in Blacks compared to Whites and Hispanics, additional comparisons of PWV and Zc were performed after adjustment for cardiac output and peripheral vascular resistance. ResultsCompared with Whites, both Blacks and Hispanics had higher levels of aortic arch PWV (4.25, 95% confidence interval [CI]: 4.15 to 4.35 m/s, vs. 4.72, 95% CI: 4.64 to 4.81 m/s, vs. 4.48, 95% CI: 4.33 to 4.63 m/s, respectively, both p < 0.05 vs. White), and Zc (64.9, 95% CI: 63.3 to 66.6 dyne·s/cm5, vs. 75.6, 95% CI: 74.0 to 77.2 dyne·s/cm5, vs. 70.1, 95% CI: 67.6 to 72.8 dyne·s/cm5, respectively, both p < 0.01 vs. White) after adjustment for age, age squared, sex, body mass index, height, mean arterial blood pressure, antihypertensive treatment, heart rate, total cholesterol, diabetes mellitus, and smoking. Compared with Hispanics, Blacks also had higher level of both PWV and Zc (both p < 0.01). Ethnic differences in PWV and Zc persisted after adjustment for cardiac output and peripheral vascular resistance. ConclusionsIn a multiethnic population-based-sample, Blacks and Hispanics had higher proximal aortic stiffness compared with Whites independent of blood pressure and relevant risk factors.

Hypertension Editors' Picks: Hypertension and Sleep.

Hypertension Editors' Picks: Hypertension and Sleep.

Abstract P248: Office and Ambulatory Brachial and Aortic Blood Pressure in Relation to Renal, Cardiac, and Vascular Organ Damage in Hypertension

It has been suggested that aortic BP could be a better predictor of target organ damage (TOD) than peripheral BP. However, studies examining such relationship by using ABPM are scarce. We aimed to examine such relationship in a cohort of hypertensive patients. A total of 208 patients (34% women; mean age: 57±12 years, 90% on antihypertensive treatment) were recruited from 4 hospital clinics in the area of Barcelona, Spain. The presence of TOD was determined if one of the following were present: cardiac, defined as the presence of LVH (LVMI ≥ 115 g/m 2 in men or ≥ 95 g/m 2 in women); renal, defined as the presence of either albuminuria (UAE ≥ 30mg/g) or reduced eGFR (&lt; 60 ml/min/1.73 m 2 , by CKD-EPI formula), or both; vascular: aortic PWV ≥ 10 m/s. Clinic (mean of 4 measurements) and 24-h brachial and aortic BP were determined by the use of the portable automated Mobil-O-Graph device. LVH was present in 37%, albuminuria (17%), reduced eGFR (14%), or both were present in 26%, and elevated aortic PWV in 18%. Overall, 51% of patients presented TOD in at least one organ, whereas 6.3% have all renal, cardiac, and vascular alterations. After adjustments for age, gender, and the use of antihypertensive treatment, odds ratios for clinic, 24-hour, daytime, and nighttime brachial and aortic SBP and pulse pressure (PP) were all significantly associated with the presence of TOD. Higher odds ratios were observed for PP, compared to SBP, and for 24-hour estimates, compared to clinic, daytime or nighttime values. The OR for 5 mmHg increase in brachial and aortic PP were respectively 1.38 (1.16-1.60) and 1.41 (1.14-1.70). PP amplification or augmentation index (clinic or 24-h-derived) were not significantly associated with the presence of TOD, after adjustments. Considering specific organ alterations, aortic SBP and PP estimates were associated with LVH and aortic PWV, but not with albuminuria or reduced eGFR. Both aortic SBP and PP are associated with the presence of TOD in hypertensive patients. The association is stronger for 24-h PP and for LVH and arterial stiffness, whereas renal alterations show a weaker association. The use of ABPM including aortic BP measurement can be of interest in predicting cardiovascular alterations in hypertension.

LBPS 02–32 THE RELATIONSHIP BETWEEN ADOLESCENT METABOLIC SYNDROME AND TARGET ORGAN DAMAGE OF ESSENTIAL HYPERTENSION

Objective: To study the relationship between metabolic syndrome and target organ damage of essential hypertension in adolescents. Design and Method: From Jan. 2007 to Sup. 2015, 186 children were enrolled who were diagnosed as essential hypertension in Capital Institute of Pediatrics. All children received the following examinations: fundus oculi, electrocardiogram, echocardiography, serum triglyceride, glucose, insulin, C peptide, uric acid, renal function, urine microalbumin, and serum and urine β2-microglobulin. According the diagnostic criteria of metabolic syndrome defined by Chinese Pediatric Society of Chinese Medical Association in 2012, all children were divided into group with metabolic syndrome (Group A) and group without metabolic syndrome (Group B). All data were collected as standard procedure and analyzed using statistic methods. Results: In all recruited adolescents, 41 patients had diagnosed as metabolic syndrome with the rate of 22.0%. The incidences of target organ damage in Group A was significantly higher than Group B (78% vs 61.4%, χ2 = 3.907, P = 0.048). Specially, the incidences of cardiovascular damage in Group A was much higher than Group B (36.6% vs 9.7%, χ2 = 17.641, P < 0.001). The average numbers of damaged target organ in Group A were significantly higher than that of Group B (1.2 ± 0.9 vs 0.8 ± 0.7, t = 2.576, P = 0.011). A ROC curve on the predictive value of fasting serum insulin concentration showed that the area under the curve was 0.638 (P < 0.05). Using a cutoff value for fasting serum insulin concentration of 15.05mIU/L produced sensitivity of 72.2% and specificity of 55.9% in predicting target organ damage, while the cutoff value of 14.81mIU/L produced sensitivity of 80.8% and specificity of 48.5% in predicting renal damage. Conclusions: Adolescent essential hypertension complicated with metabolic syndrome had a much higher incidence of target organ damage than those without metabolic syndrome. Specially, cardiovascular damage was more common in those adolescents with metabolic syndrome. Fasting serum insulin concentration was very important for predicting target organ damage.

AMBULATORY BLOOD PRESSURE AND LEFT VENTRICULAR DIASTOLIC DYSFUNCTION: A COMMUNITY-BASED STUDY IN AN ELDERLY COHORT

Left ventricular diastolic dysfunction (LVDD) is frequent in the elderly, and is an independent predictor of mortality, cardiovascular events, and heart failure development. Ambulatory blood pressure (ABP) is a better predictor of target organ damage and cardiovascular events than office BP. We

Assessment of central blood pressure as a predictor of target organ damage in children with primary hypertension

Introduction. Central systolic blood pressure (cSBP) is assumed to be the best indicator of cardiovascular risk caused by elevated blood pressure. However, there are no data on the usefulness of cSBP measurments in the assessment of the risk of target organ damage (TOD) in hypertensive children. Aim. The aim of study was to evaluate the usefulness of noninvasive measurements of cSBP, AugP and AugInd as predictors of increased left ventricular hypertrophy (LVH) and increased carotid intima-media thickness (cIMT) in children with primary hypertension. Material and methods. 114 children (25 girls), mean age 15.2 ± 2.5 years, referred because of elevated blood pressure and with excluded secondary hypertension, were included in the study. In all patients, 24h ambulatory blood pressure monitoring (ABPM), cSBP, central pulse pressure (cPP), AugP, AugInd, cardiac index (CI), total peripheral resistance (TPR), pulse wave velocity (PWV), LVMI and cIMT were measured. Results. In 62 patients white coat hypertension was diagnosed, 9 had ambulatory hypertension and 43 had severe ambulatory hypertension. Children with severe ambulatory hypertension had greater AugP, CI and carotid wall cross sectional area (WCSA) and lower TPR. cSBP correlated with WCSA (p = 0.015; r = 0.255) and AugP with LVMI (p = 0.02; r = 0.220). ABPM had greater sensitivity and lower specificity for predicting LVH than cSBP. ABPM and cSBP had similar sensitivity and specificity as predictors of cIMT and WCSA. Conclusions. Although sensitivity and specificity of cSBP and ABPM as predictors of arterial injury were similar, ABPM performed better as a predictor of LVH. The results of our study indicate a much higher risk of TOD in children with severe ambulatory hypertension and show that the assessment of cSBP, which is also a predictor of LVH, may be a new criterion for drug therapy implementation.

Całodobowy profil ciśnienia tętniczego a czynność nerek u chorych na cukrzycę typu 1

Background and aims. Dipping profile in ambulatory blood pressure monitoring (ABPM) may be a good predictor of target organ damage in patients with type 1 diabetes. The aim of the study was to analyze the correlation between the blood pressure profile in ABPM and other predictors of early kidney damage in type 1 diabetes. Material and methods. We examined 132 type 1 diabetes patients with normal blood pressure and 22 type 1 diabetes patients treated with antihypertensive drugs. ABPM was performed in each patient. Urine albumin to creatinine ratio (UACR) was assessed and estimated glomerular filtration rate (eGFR) was estimated based on serum cystatin C concentration. The association between blood pressure profile in ABPM and renal function was analyzed. Results. In normotensive patients dipper status did not have any impact on renal function. Non-dippers had lower day systolic and diastolic blood pressure and higher night systolic and diastolic blood pressure than dippers. Day systolic blood pressure was negatively correlated with eGRF estimated with cystatin C. In hypertensive patients non-dippers had higher urine albumine to creatinine ratio than dippers. Conclusions. In normotensive type 1 diabetic patients non-dipping status does not seem to be good predictor of early renal complications. However, in type 1 diabetics treated for hypertension, non-dipping could reflect probable kidney damage. GFR estimated with cystatin C could be more sensitive than albuminuria predictor of early kidney damage in type 1 diabetes.

PP.10.19

Objective: Ambulatory blood pressure monitoring (ABPM) is being increasingly used in the assessment of hypertension in all age groups, confirming the continuous relationship between blood pressure (BP) and cardiovascular risk amongst older people. Moreover, ABPM seems to be is a more accurate predictor of cardiovascular morbidity and mortality than clinic measurements, providing a better estimate of BP load and identification of white-coat hypertension, a known common phenomenon in the elderly. The present analysis was undertaken to evaluate blood pressure profiles in subjects over 80 years old referred to our institution for ABPM in comparison with young subjects (18–30 years old). In view of the lack of data regarding ABPM in elderly people, we tried to better understand additional value of ABPM over office BP measuring and its reflections on patients’ treatment and follow-up. Design and method: 429 ABPMs of subjects aged 80 and over compared with 210 ABPMs of subjects between 18 and 30 years, referred at our Institution in the period 2000- 2014 were analyzed; all the recordings were performed using the same oscillometric device (TM 2430), in order to avoid confounding factors; all ABPMs fulfilled both the following criteria: > 23 hours recording and at least 2 valid measurements/hour (>70 % of total measures). Results: We identified hypertensive and normotensive subjects; hypertensives were furtherly subdivided in white coat, masked, isolated systolic, systo-diastolic and diastolic isolated hypertensives. Dipper and non dipper status (difference day- night > 10%) and post prandial fall were also calculated. Morning surge phenomenon and hypotension were also considered. Conclusions: Twenty-four-hour ABPM provides many measurements for better analysis and is likely to eliminate the stress of office visits and observer bias and proves to be a more accurate predictor of target organ damage and cardiovascular risk than routine office BP measurements. This tool seems to be of a certain importance even in the better evaluation of elderly subjects and in their possible therapeutic approach. White coat phenomenon seems to be a crucial parameter to be taken into account not only in younger subjects but also in elderly.

Central hemodynamics in risk assessment strategies: additive value over and above brachial blood pressure.

Although the clinical relevance of brachial blood pressure (BP) measurement for cardiovascular (CV) risk stratification is nowadays widely accepted, this approach can nevertheless present several limitations. Pulse pressure (PP) amplification accounts for the notable increase in PP from central to peripheral arterial sites. Target organs are more greatly exposed to central hemodynamic changes than peripheral organs. The pathophysiological significance of local BP pulsatility, which has a role in the pathogenesis of target organ damage in both the macro- and the microcirculation, may therefore not be accurately captured by brachial BP as traditionally evaluated with cuff measurements. The predictive value of central systolic BP and PP over brachial BP for major clinical outcomes has been demonstrated in the general population, in elderly adults and in patients at high CV risk, irrespective of the invasive or non-invasive methods used to assess central BP. Aortic stiffness, timing and intensity of wave reflections, and cardiac performance appear as major factors influencing central PP. Great emphasis has been placed on the role of aortic stiffness, disturbed arterial wave reflections and their intercorrelation in the pathophysiological mechanisms of CV diseases as well as on their capacity to predict target organ damage and clinical events. Comorbidities and age-related changes, together with gender-related specificities of arterial and cardiac parameters, are known to affect the predictive ability of central hemodynamics on individual CV risk.

Exercise testing in hypertensive patients for assessing the cardiovascular protective potential of antihypertensive drugs

Exercise testing is an established noninvasive tool in cardiology used to diagnose and guide treatment in individuals with suspected or confirmed coronary artery disease. Owing to the wealth of information it provides, exercise testing is also being utilized to evaluate prehypertensive stages, characterize hypertension, assess tolerance to exercise and the efficacy of antihypertensive therapies, and predict target organ damage and cardiovascular risk. The literature on exercise tolerance tests is relatively limited since these studies are difficult to conduct although they represent a valuable test for evaluating the benefits of antihypertensive therapies beyond their blood-pressure-lowering efficacy at rest or during exercise. Such a setting can be immensely useful for the evaluation and for the differentiation of treatments, especially in patients with evident rises in systolic blood pressure and with concomitant diseases, who are at higher risk of stroke. Exercise-induced increase in systolic blood pressure from rest to peak exercise should therefore be used as the primary efficacy variable. There is growing evidence that central pressure is a better predictor for cardiovascular risk than peripheral blood pressure, since this variable takes into account the overall effect of vascular aging and increased arterial stiffness that age and other concomitant diseases may induce. It is also important to include central aortic blood pressure and biomarkers of hypertension and cardiac disease in the overall assessment.

Home versus ambulatory and office blood pressure in predicting target organ damage in hypertension

Studies have shown that ambulatory blood pressure (BP) is more closely related to preclinical target organ damage than office measurements. A review and meta-analysis of studies investigating the association of home BP measurements with target organ damage was performed. A PubMed and Cochrane Library search (1950-2011) revealed 23 studies reporting comparative data of home BP versus ambulatory and/or office measurements in terms of their association with several indices of target organ damage. Correlation coefficients were pooled by random-effects model meta-analysis. Fourteen studies (n = 2485) assessing echocardiographic left ventricular mass index (LVMI) showed similar correlations with home (coefficients r = 0.46/0.28, systolic/diastolic) as with ambulatory BP (0.37/0.26, P = NS for difference versus home BP), and superior to office measurements (r = 0.23/0.19, P < 0.001/0.009 for difference versus home BP). Four methodologically heterogeneous studies assessing the glomerular filtration rate (n = 609) could not be pooled or lead to a concrete result. Four studies assessing carotid intima-media thickness (n = 1222), three assessing pulse wave velocity (n = 720) and two assessing urinary protein excretion (n = 156) showed no difference in pooled correlation coefficients with home versus office BP measurements. With all the measurement methods SBP was more closely associated with target organ damage than DBP. These data suggest that home BP is as good as ambulatory monitoring and superior to office measurements in regard to their association with preclinical organ damage assessed by echocardiographic LVMI. More research is required to evaluate the relationship of home BP with other indices of target organ damage.

Increasing the Validity and Efficiency of Blood Pressure Estimates Using Ambulatory and Clinic Measurements and Modern Missing Data Methods

Ambulatory blood pressure monitoring (ABPM) is considered the gold standard for BP measurement, compared to clinic BP measurements (CBP), which are a less valid predictor of target organ damage and cardiovascular events. However, ABPM is considerably more expensive than CBP, leaving BP researchers with a difficult dilemma: Use the less efficient CBP measure, or bear the cost of the more expensive ABPM. Recent developments in missing data methods, notably the two-method measurement (TMM) design, address this problem. With the TMM design, all research participants receive the less expensive CBP measure, but only a random subset receives the more expensive ABPM. The total number of participants must be increased, with additional participants receiving only CBP measurements. Even so, the TMM still reduces costs. We applied the TMM approach, which makes use of a "bias correction" structural equation model, to an empirical data set in which data were available for ABPM and CBP, as well as an echocardiographic measure of left ventricular mass (LVM). Based on an estimated fivefold difference in cost for using ABPM compared to CBP, we found that statistical power can be considerably increased, or that BP measurement costs can be considerably reduced, when using this planned missing data design. These benefits were observed with no loss of predictive validity (i.e., the observed association between BP and LVM). This suggests that the TMM design is a promising technique that in some studies may be able to decrease costs and/or increase one's power to detect effects.

Home blood pressure monitoring may make office measurements obsolete

he conventional measurement of blood pressure(BP) in the office or clinic has been the cornerstonefor hypertension management for decades. How-ever, because of the white-coat and the masked hyper-tension phenomena, out-of-office BP monitoring withambulatory or home measurements is often required [1].ExtensiveresearchonambulatoryBPmonitoringhasestab-lished its role as the most accurate tool for hypertensiondiagnosis [1–3].Onthecontrary,despitetheincreasinguseof home BP monitoring by hypertensive patients in thedaily management of their high BP condition, research inthisfield,inparticularwhenconsideringoutcometrials,hasbeen delayed as compared to ambulatory BP monitoring[4,5].