Identification of the hemodynamic modulators and hemodynamic status in uncontrolled hypertensive patients.

Only 20-30% out of the treated hypertensive patients in Europe are achieving blood pressure (BP) control. Among other recognized factors, these poor results could be attributable to the fact that for many doctors it is very difficult to detect which is the predominant hemodynamic cause of the hypertension (hypervolemia, hyperinotropy or vasoconstriction). The aim of the study was to use non-invasive thoracic electrical bioimpedance (TEB) to evaluate hemodynamic modulators and subsequent hemodynamic status in uncontrolled hypertensive patients, receiving at least two antihypertensive drugs. A number of 134 uncontrolled hypertensive patients with essential hypertension were evaluated in nine European Hypertension Excellence centers by means of TEB (the HOTMAN(®) System). Baseline office systolic and diastolic BP averaged 156/92 mmHg. Hemodynamic measurements show that almost all patients (98.5%) presented at least one altered hemodynamic modulator: intravascular hypervolemia (96.4%) and/or hypoinotropy (42.5%) and/or vasoconstriction (49.3%). Eleven combinations of hemodynamic modulators were present in the study population, the most common being concomitant hypervolemia, hypoinotropy and vasoconstriction in 51(38%) patients. Six different hemodynamic states (pairs of mean arterial pressure and stroke index) were found. Data suggest that there is a strong relation between hypertension and abnormal hemodynamic modulators. This method might be helpful for treatment individualization of hypertensive patients.

Automated office blood pressure measurements in primary care are misleading in more than one third of treated hypertensives: The VALENTINE-Greece Home Blood Pressure Monitoring study.

BACKGROUND: This study assessed the diagnostic reliability of automated office blood pressure (OBP) measurements in treated hypertensive patients in primary care by evaluating the prevalence of white coat hypertension (WCH) and masked uncontrolled hypertension (MUCH) phenomena. METHODS: Primary care physicians, nationwide in Greece, assessed consecutive hypertensive patients on stable treatment using OBP (1 visit, triplicate measurements) and home blood pressure (HBP) measurements (7 days, duplicate morning and evening measurements). All measurements were performed using validated automated devices with bluetooth capacity (Omron M7 Intelli-IT). Uncontrolled OBP was defined as ≥140/90 mmHg, and uncontrolled HBP was defined as ≥135/85 mmHg. RESULTS: A total of 790 patients recruited by 135 doctors were analyzed (age: 64.5 ± 14.4 years, diabetics: 21.4%, smokers: 20.6%, and average number of antihypertensive drugs: 1.6 ± 0.8). OBP (137.5 ± 9.4/84.3 ± 7.7 mmHg, systolic/diastolic) was higher than HBP (130.6 ± 11.2/79.9 ± 8 mmHg; difference 6.9 ± 11.6/4.4 ± 7.6 mmHg, p < 0.001). WCH phenomenon (high OBP with low HBP) was observed in 22.7% of the patients, MUCH (low OBP with high HBP) in 15.8%, uncontrolled hypertension (high OBP with high HBP) in 29.9%, and controlled hypertension (low OBP with low HBP) in 31.6%. In multivariate logistic regression analysis, WCH was determined by stage-1 systolic hypertension (odds ratio [OR] 8.6, 95% confidence intervals [CI] 5.7, 13.1) and female gender (OR 1.6, 95% CI 1.1, 2.4), whereas MUCH was determined by high-normal systolic OBP (OR 6.2, 95% CI 3.8, 10.1) and male gender (OR 2.0, 95% CI 1.2, 3.1). CONCLUSIONS: In primary care, automated OBP measurements are misleading in approximately 40% of treated hypertensive patients. HBP monitoring is mandatory to avoid overtreatment of subjects with WCH phenomenon and prevent undertreatment and subsequent excess cardiovascular disease in MUCH.

Can an electronic device with a single cuff be accurate in a wide range of arm size? Validation of the Visomat Comfort 20/40 device for home blood pressure monitoring.

An appropriate cuff according to the individual's arm circumference is recommended with all blood pressure (BP) monitors. An electronic device for home monitoring has been developed (Visomat Comfort 20/40) that estimates the individual's arm circumference by measuring the cuff filing volume and makes an adjustment of measured BP taking into account the estimated arm circumference. Thus the manufacturer recommends the use of a single cuff for arm circumference 23-43 cm. The device accuracy was assessed using the European Society of Hypertension International Protocol. Simultaneous BP measurements were obtained in 33 adults by two observers (connected mercury sphygmomanometers) four times, sequentially with three measurements taken using the tested device. Absolute device-observer BP differences were classified into < or =5, < or =10 and < or =15 mm Hg zones. For each participant the number of measurements with a difference < or =5 mm Hg was calculated. The device produced 60/89/97 measurements within 5/10/15 mm Hg respectively for systolic BP, and 72/97/98 for diastolic. Twenty-three subjects had at least two of their systolic BP differences < or =5 mm Hg and three had no differences < or =5 mm Hg (for diastolic 27 and 1, respectively). Mean device-observer BP difference (systolic/diastolic) was 3.7 +/- 5.6/-1.5 +/- 4.7 mm Hg (4.7 +/- 4.9/ - 1.7 +/- 4.3 in arm circumference 23-29 cm [39 readings] and 3.1 +/- 5.9/-1.4 +/- 5.0 in arm 30-34 cm [60 readings], P=NS). In conclusion, the device fulfils the International Protocol requirements and can be recommended for clinical use. Interestingly, the device was accurate using a single cuff in a wide range of arm circumference (23-34 cm). This study provides no information about the device accuracy in larger arms.

A novel cuffless device for self-measurement of blood pressure: concept, performance and clinical validation.

A pocket-size cuffless electronic device for self-measurement of blood pressure (BP) has been developed (Freescan, Maisense Inc., Zhubei, Taiwan). The device estimates BP within 10 s using three embedded electrodes and one force sensor that is applied over the radial pulse to evaluate the pulse wave. Before use, basic anthropometric characteristics are recorded on the device, and individualized initial calibration is required based on a standard BP measurement performed using an upper-arm BP monitor. The device performance in providing valid BP readings was evaluated in 313 normotensive and hypertensive adults in three study phases during which the device sensor was upgraded. A formal validation study of a prototype device against mercury sphygmomanometer was performed according to the American National Standards Institute/Association for the Advancement of Medical Instrumentation/International Organization for Standardization (ANSI/AAMI/ISO) 2013 protocol. The test device succeeded in obtaining a valid BP measurement (three successful readings within up to five attempts) in 55-72% of the participants, which reached 87% with device sensor upgrade. For the validation study, 125 adults were recruited and 85 met the protocol requirements for inclusion. The mean device-observers BP difference was 3.2±6.7 (s.d.) mm Hg for systolic and 2.6±4.6 mm Hg for diastolic BP (criterion 1). The estimated s.d. (inter-subject variability) were 5.83 and 4.17 mm Hg respectively (criterion 2). These data suggest that this prototype cuffless BP monitor provides valid self-measurements in the vast majority of adults, and satisfies the BP measurement accuracy criteria of the ANSI/AAMI/ISO 2013 validation protocol.

Self-monitoring of blood pressure at home: how many measurements are needed?

OBJECTIVE: To determine the minimum number of self-measurements of blood pressure at home (HBP) necessary to provide the maximum clinically important benefit. METHODS: Hypertensive patients were randomly allocated to monitor HBP for 2 weeks (6 work days, duplicate measurements, twice daily) or ambulatory blood pressure for 24 h. The alternative measurement was then performed. Clinic blood pressure was measured at the beginning and the end of the study. Criteria for reliability of HBP were the stabilization of mean HBP, its variability (SD) and the correlation coefficient r for relationship of HBP with ambulatory blood pressure. The reproducibility of HBP was quantified using test-re-test correlations and the SD of differences between average HBP values of different days. RESULTS: We studied 189 patients (79 being administered stable antihypertensive treatment). Average HBP (137.5 +/- 16.2/85.9 +/- 9.9 mmHg) was lower than average clinic blood pressure (P<0.001) and higher than 24 h and night-time ambulatory blood pressures (P<0.001). There was no difference between HBP and daytime ambulatory blood pressure. On day 1 HBP was higher than it was on each of days 2-6, with no difference among days 2-6. When data for the initial day for monitoring of HBP were excluded from analysis, average HBP was reduced. Only a modest improvement in the reliability of HBP on day 2 (reductions in mean HBP and its SD and an increase in r with ambulatory blood pressure) was achieved by averaging more readings taken on succeeding days. At least two monitoring days were needed for the reproducibility of HBP to be superior to that of clinic blood pressure. CONCLUSIONS: These results suggest that determining average HBP of the second and third work days, is the minimum programme that provides a reliable estimate of HBP.

Diagnosis of hypertension using home or ambulatory blood pressure monitoring: comparison with the conventional strategy based on repeated clinic blood pressure measurements.

OBJECTIVE: To investigate whether measurement of blood pressure at home (HBP) and by ambulatory monitoring (ABP) are reliable alternatives to the traditional strategy for the diagnosis of hypertension based on blood pressure measurement on repeated clinic visits (CBP). DESIGN: Comparison of the diagnosis of hypertension based on HBP (on six workdays) or ABP monitoring (two occasions) with that based on CBP (five visits within 3 months). SETTING: Outpatient hypertension clinic. PARTICIPANTS: We enrolled 133 individuals with a diastolic CBP of 90-115 mmHg on the initial visit. MAIN OUTCOME MEASURES: CBP, HBP and ABP values, and the diagnosis of hypertension. RESULTS: Hypertension was diagnosed in 70, 63 and 56% of individuals using the CBP, ABP and HBP methods respectively (P = 0.04). Agreement in the diagnosis of hypertension between all three methods was found in 59% of individuals. Disagreement between CBP and ABP was found in 27%, between CBP and HBP in 29% and between ABP and HBP in 26% of individuals. The sensitivity, specificity and positive and negative predictive values of ABP to diagnose hypertension correctly were 76, 67, 85 and 53% respectively; for HBP the respective values were 69, 77, 88 and 51%. The same parameters for HBP compared with ABP in the detection of white-coat hypertension were 61, 79, 48 and 86% respectively. CONCLUSIONS: Indiscriminate use of HBP or ABP monitoring in the evaluation of all individuals with high blood pressure will probably result in confusion and therefore should be discouraged. However, in the detection of white-coat hypertension, HBP appears to be useful as a screening test, which, if positive, requires confirmation with ABP monitoring.

Home self-monitoring of blood pressure: is fully automated oscillometric technique as good as conventional stethoscopic technique?

Home blood pressure (HBP) measurement is becoming increasingly popular as an additional source of information for the practicing physician. Whether HBP measured with a fully automated oscillometric device (oHBP) is more reliable than HBP measured with an aneroid sphygmomanometer and a stethoscope (sHBP) remains unclear. We compared sHBP with oHBP using as a reference method daytime ambulatory blood pressure (ABP), as this is believed to be a better index of an individual's overall level of pressure. Forty-six hypertensive patients measuring HBP with aneroid devices were retrained by a standard 30 min protocol that included training in the technique of measurement, checking patients' devices, and testing patients' performance in stethoscopic measurement. Patients were randomized to measure for 2 weeks either sHBP using their own calibrated aneroid devices or oHBP using a validated fully automated oscillometric device (Omron HEM-705CP). Then 24 h ABP monitoring was performed (SpaceLabs 90207) and patients crossed over for a second 2 week period by using the alternative HBP measurement technique. Mean sHBP was not different from mean oHBP, and there was a close correlation between them (r = 0.82/0.76 for systolic/diastolic BP, P < .001). Daytime ABP was not different from oHBP or sHBP and was closely related to both of them (oHBP, r = 0.59/0.72 systolic/diastolic BP, P < .001; sHBP, 0.50/0.65, P < .001). Age was significantly related with diastolic ABP-sHBP difference (r = 0.33, P < .05). These results suggest that HBP measured with validated fully automated oscillometric devices is equally reliable in predicting average ABP as that measured with calibrated aneroid sphygmomanometers used by very carefully trained patients. In clinical practice, HBP monitoring by using reliable automated devices is probably more feasible than to achieve a high standard of stethoscopic HBP measuring technique.

White coat effect detected using self-monitoring of blood pressure at home: comparison with ambulatory blood pressure.

The objective of the study was to investigate whether home blood pressure (HBP) is a reliable alternative to ambulatory blood pressure (ABP) for the detection of the white coat effect (WCE). Hypertensive patients were randomized to measure HBP for 2 weeks or ABP for 24 h. The alternative measurement was then performed. Clinic blood pressure (CBP) was measured in the beginning and end of the study. Subjects with a difference of > or = 20 mm Hg systolic or > or = 10 mm Hg diastolic BP between CBP and awake ABP or CBP and HBP, were classified as clinic reactors. A total of 189 patients completed the study (79 on stable antihypertensive treatment). There was no difference in the magnitude of WCE assessed using the ABP or the HBP method (mean discrepancy, systolic BP: -1.5 +/- 11.7 mm Hg, 95% CI -3.2, 0.2; diastolic BP: 0.9 +/- 7.0, 95% CI -0.1, 1.9). A strong association existed between WCE calculated using the HBP or the ABP method (r = 0.64/0.59 systolic/diastolic, P < .001). The proportion of patients classified as clinic reactors was identical using the HBP or the ABP method (25.9%). Agreement between methods in the classification of clinic reactors was found in 147 patients (78%). The sensitivity and specificity of the HBP method to classify correctly clinic reactors (ABP method used as the standard) were 57% and 85%, respectively, whereas its positive and negative predictive value were 57% and 85%. These results indicate that HBP is not appropriate as an alternative to ABP diagnostic testing in the detection of WCE. Nevertheless, HBP appears useful as a screening test for the detection of this phenomenon.

Home blood pressure normalcy: the Didima study.

To evaluate reference values of home blood pressure (HBP) a cross-sectional community study was conducted on 694 adult subjects (aged > or = 18 years) of the village Didima in southern Greece (participation rate 76.4%). Clinic blood pressure (CBP) was measured on two visits (triplicate measurements, mercury sphygmomanometer) and HBP on 3 workdays (duplicate morning and evening measurements, oscillometric devices; Omron HEM 705CP). After exclusion of 132 subjects (103 treated hypertensives and 29 with incomplete data), 562 subjects were analyzed (mean +/- SD aged 51.2 +/- 17.2 years, 42.7% men). Average HBP (120.0 +/- 17.8/72.6 +/- 8.8 mm Hg, systolic/diastolic) was strongly correlated (P < .0001) with CBP (118.7 +/- 17.7/73.8 +/- 10.5 mm Hg). Systolic CBP was 1.3 mm Hg lower than HBP (P < .01, 95% confidence interval 0.4, 2.2), whereas diastolic CBP was 1.2 mm Hg higher than HBP (P < .0001, 95% confidence interval 0.6, 1.7). The threshold of HBP normality determined using three different approaches was 1) 139.7/83.0 mm Hg (systolic/diastolic) using the distribution criterion (95th percentile of the HBP distribution among 476 normotensive subjects); 2) 139.7/85.8 mm Hg using the correspondence criterion (the percentiles of the CBP distribution that correspond to CBP > or = 140/90 mm Hg were estimated, and the levels of BP that correspond to these same percentiles on the HBP distribution were calculated); and 3) 137.4/82.7 mm Hg using the regression criterion (calculation of the levels of HBP that correspond to CBP of 140/90 mm Hg using the regression equation between HBP and CBP). Overall, the findings of the three criteria suggest that average HBP < 137/82 mm Hg might be considered as probably normal, > 140/86 mm Hg as probably abnormal, and within these limits as borderline. Until mortality-based prospective data are available, this approach might be useful in the interpretation of HBP in clinical practice.

Prevalence, awareness, treatment, and control of hypertension in Greece: the Didima study.

To assess the prevalence and the levels of awareness, treatment, and control of hypertension in the rural population of Greece, a cross-sectional survey of the total population age > or =18 years of the village Didima was conducted. The survey included an interview and blood pressure (BP) measurement on two clinic visits. Hypertension was defined as systolic BP > or = 140 mm Hg and or diastolic BP > or = 90 mm Hg or current treatment with antihypertensive drugs. The same BP threshold was used for the assessment of hypertension control. A total of 694 inhabitants participated (response rate 76.4%), and 665 were analyzed. The prevalence of hypertension was 28.4% (men 30.2%, women 27.1%). Of the subjects age > or =65 years, 50% had hypertension. Although 73% of participants were measuring their BP at least once a year, overall, 39.2% of hypertensives were unaware of the diagnosis (men 50%, women 30.5%), 6.3% were aware but not treated (men 4.8%, women 7.6%), 27.5% were treated but not controlled (men 22.6%, women 31.4%), and 27% were treated and controlled (men 22.6%, women 30.5%). These results suggest that, in the rural population of Greece, hypertension is a common risk factor with considerable potential for improvement in levels of control.

Does the antihypertensive response to angiotensin converting enzyme inhibition predict the antihypertensive response to angiotensin receptor antagonism?

To test the hypothesis that the antihypertensive response to angiotensin converting enzyme (ACE) inhibition can predict the response to angiotensin II type I receptor (AT1R) antagonism, 33 hypertensive patients were randomized to receive lisinopril (20 mg) or losartan (50 mg) for 5 weeks. Patients were then crossed-over to the alternative treatment for a second 5-week period. Twenty-four-hour ambulatory BP (ABP) was measured before randomization and on the final day of each period. The agreement in ABP response between the two drugs was assessed using the following approaches: Subjects were classified as responders and nonresponders using as a threshold an arbitrary level of response (ABP fall > or = 10 mm Hg systolic or > or = 5 mm Hg diastolic) or the median ABP response achieved by each of the drugs. Disagreement between the two drugs in the responders-nonresponders classification was expressed as the proportion of subjects whose ABP responded to one of the drugs only. Lisinopril was more effective than losartan in reducing ABP (mean difference 4.7+/-8.1/3.3+/-5.7 mm Hg, systolic/diastolic, P < .05). Disagreement in the antihypertensive response between the two drugs was found in 39%/33% of subjects for systolic/diastolic ABP using the arbitrary response criterion (33%/39% using the median response criterion). Significant correlations were found between the responses to lisinopril and losartan (r = 0.47/0.59, systolic/diastolic, P < .01). We conclude that in more than one third of hypertensive subjects, the BP response to ACE inhibition fails to predict the response to AT1R antagonism and vice versa. These data suggest that there are differences between these two drug classes that are not only of theoretical but also of practical significance.

Genomic and chromosomal organization of Ty1- copia-like sequences in Olea europaea and evolutionary relationships of Olea retroelements.

The Ty1- copia-like retrotransposon is one of the commonest class of transposable elements in the plant kingdom, often comprising several percent of the total DNA content. We aimed to study the evolutionary relationships of Olea retroelements, using part of the reverse transcriptase domain, as well as the genomic and chromosomal organization of these sequences in Olea europaea chromosomes and their transcription activity and copy number. Fourteen clones, that were isolated from four different species, were sequenced and a phylogenetic tree was constructed based on their predicted amino acids. Five clones derived from O. europaea were clustered together with a 87% nucleotide sequence homology and two Olea oleaster clones showed 98% sequence homology. The rest of the clones showed heterogeneity among them, leading to a common ancestral transposon that existed before the genus arose. The Ty1- copia-like sequences have a dispersed genomic organization, physically distributed on all chromosomes, showing minor clustering in some cases and low copy numbers in the smallest chromosome pair. The total copy number in the O. europaea genome was estimated by dot blotting to be 40,000 in a haploid nucleus, but a number of these are non-functional since the sequenced clones contained stop codons and frame-shifts. Some Ty1- copia-like copies, present in O. europaea, were found to be methylated, while no differences in methylation were observed between DNA isolated from young leaves and callus-suspension cultures.

Angiotensin receptor blockade in the challenging era of systolic hypertension.

Systolic blood pressure is a major cardiovascular risk factor which is often associated with arterial stiffness. Markers of arterial stiffness, such as pulse pressure and carotid-femoral pulse wave velocity, have been proved independent predictors of cardiovascular risk. Recent evidence suggests that the renin-angiotensin system is involved in the pathogenesis of systolic hypertension and arterial stiffness. Outcome trials have shown impressive cardiovascular protection by reducing systolic blood pressure (BP) with drug treatment. However, in clinical practice systolic hypertension remains largely uncontrolled, first, because systolic BP goal is more difficult to be reached than diastolic and, second, because physicians are often reluctant to intensify treatment in patients with systolic BP close to 150 mmHg. Recent trials have focused on the effects of antihypertensive drugs not only on blood pressure, but also on pulse pressure and pulse-wave velocity. Blockade of the renin-angiotensin-aldosterone system, using angiotensin-converting enzyme inhibitors and more recently angiotensin receptor blockers, has been shown to provide beneficial effects on arterial stiffness that appear to be independent of their antihypertensive effects. Recent outcome trials have shown significant cardiovascular protection with angiotensin receptor blockers. These drugs have an excellent placebolike profile of adverse effects which is maintained when these drugs are combined with low-dose diuretics. Therefore, an angiotensin receptor blocker-based treatment strategy appears to be an attractive and evidence-based approach for the management of systolic hypertension, the reduction of arterial stiffness and the prevention of cardiovascular disease.

Aggressive blood pressure control in general practice (ABC-GP) study: can the new targets be reached?

Based on outcome trials, guidelines for hypertension management recommend lower blood pressure (BP) goals using an individualized treatment strategy (IND) and referral to a specialist of patients uncontrolled after 6 months of treatment. This study aimed to evaluate the performance of General Practitioners (GPs) in reaching the recommended BP goals using the IND, or a stepwise treatment strategy (STEP) as used in the outcome trials. Trained GPs were randomized to reach the BP goals within 6 months using the IND or a STEP strategy in untreated or treated uncontrolled hypertensives. In all, 24 GPs recruited 528 patients of whom 443 were analysed (mean age 65+/-9 years, 42% men, 70% treated, STEP/IND 12/12 GPs, 231/211 patients). After 6 months, 83% of the patients had reached the diastolic BP goal, whereas only 51% the systolic (P<0.0001 for difference). Factors associated with uncontrolled systolic BP were diabetes, age >60 years and triple antihypertensive therapy at baseline. A faster BP reduction was achieved during the first 3 months using the STEP strategy, but at the cost of using more drugs (combination therapy in 68/59% for STEP/IND, P=0.06). At 6 months similar rates of control were achieved with the two strategies. In conclusion, in primary care the diastolic BP goal can be reached within 6 months in the majority of patients, whereas systolic BP remains uncontrolled in 50% of the cases. The IND should be the recommended treatment strategy, but further investigation is required on the reasons for treatment failure and the optimal strategy for its improvement.

Diagnostic value of strategy for the detection of white coat hypertension based on ambulatory and home blood pressure monitoring.

An algorithm has been proposed for the detection of white coat hypertension among subjects with elevated blood pressure (BP) on at least three clinic visits using home BP monitoring (screening test) and, if this is low, ambulatory BP monitoring (diagnostic test). This study aims to test this strategy in practice. The proposed algorithm was applied in 133 untreated subjects with elevated BP assessed in a previous prospective study using repeated clinic, home and ambulatory BP measurements. The proportions of detected and missed cases of white coat hypertension and the diagnostic value of the algorithm were calculated. By applying the algorithm, 99 subjects (74%) were found eligible for home measurements and 35 (26%) for ambulatory monitoring. There were 38 subjects with white coat hypertension (38%), of whom 15 (39%) were not detected by the proposed strategy. The sensitivity, specificity, and the positive and negative predictive value of the algorithm to diagnose white coat hypertension were 61, 81, 66 and 77%, respectively. Of the 34 subjects with normal BP on the third clinic visit, 15 (42%) had elevated home and/or ambulatory BP. These data suggest that, using the proposed strategy, many white coat hypertensives may remain undetected and may receive unnecessary long-term drug treatment. Therefore, more research is needed on the optimal strategy for detecting white coat hypertension in clinical practice.

Blood pressure during siesta: effect on 24-h ambulatory blood pressure profiles analysis.

Blood pressure (BP) during siesta declines to levels similar to those of night time sleep. The objective of the study was to assess the effect of siesta on 24-h ambulatory BP (ABP) data. Two different approaches were employed for the definition of day and night periods: (1) actual patient reported day and night intervals (ACT) with siesta period analysed as a third time period; and (2) arbitrary day and night time intervals (ARB) with the presence of siesta being ignored. A total of 203 24-h ABP recordings were analysed, with a siesta during ABP monitoring reported in 154 of them. Mean siesta BP was very close to ACT night time BP. Among recordings with a siesta, ACT daytime BP was higher and night time BP lower than the corresponding ARB BPs (P < 0.001). The magnitude of night time BP drop was greater with ACT intervals, resulting in a lower percentage of non-dippers (P < 0.001). Among 49 recordings without a siesta, differences between ACT and ARB BPs were less pronounced for daytime but not for night time. Differences in the magnitude of nocturnal BP drop between ACT and ARB periods, although statistically significant, did not affect the prevalence of non-dippers. In conclusion, analysis of 24-h BP profiles by using ARB instead of ACT day and night intervals results in underestimation of the nocturnal BP drop and overestimation of the proportion of non-dippers. This bias is more pronounced in patients who take a siesta during ABP monitoring.

Home monitoring of blood pressure: limited value in general practice.

To investigate the reliability of home blood pressure (HBP) measurement as it is generally used in practice, we studied 50 consecutive newly referred hypertensive patients that were measuring HBP for at least 6 months before referral. No specific instructions on the technique of HBP measurement were given to the patients. HBP was compared to clinic BP (CBP) by using daytime ambulatory BP (ABP) as a reference method. The technique of HBP measurement used by the patients was assessed on the basis of a detailed questionnaire and the accuracy of the devices was tested against a mercury column. There was no difference between the degree of similarity of ABP with HBP or CBP (mean value of discrepancies and correlation coefficients) for systolic BP (SBP) and little difference for diastolic BP (DBP). However, the variability of discrepancies between HBP and ABP was equal to the corresponding variability between CBP and ABP, indicating that HBP was not better predictor of ABP than CBP. Although patients measured HBP more frequently than generally recommended, poor standardisation of measurement and wrong technique were particularly common. In conclusion, in the present study HBP measurement offered no advantage over CBP in predicting ABP. The theoretical advantages of HBP may be partially offset by incorrect technique and less standardised conditions of measurement. Without patients education and regular maintenance of devices HBP offers no advantage over CBP and should not be used. (This article is based on data presented at the 7th European Hypertension Society Meeting in Milan, June 1995).

Assessment of drug effects on blood pressure and pulse pressure using clinic, home and ambulatory measurements.

This study investigated the differences in the effect of an angiotensin converting enzyme inhibitor (ACEI) compared with an angiotensin receptor blocker (ARB) on blood pressure (BP) and pulse pressure (PP) measured in the clinic (CBP and CPP, respectively), at home (HBP, HPP) and with ambulatory monitoring (ABP, APP). Twenty-seven hypertensive patients were randomised to receive lisinopril (20 mg) or losartan (50 mg) for 5 weeks, and were subsequently crossed-over to the alternative treatment for a second 5-week period. Measurements of CBP, 24-h ABP and 5-days HBP were performed before randomisation and at the end of each treatment period. All measurement methods showed that lisinopril was more effective than losartan in reducing BP. However, the difference between the two drugs was demonstrated with greater precision using HBP (P<0.001) than 24-h ABP (P<0.01), whereas the poorest precision for demonstrating this difference was provided by CBP (P<0.05). Lisinopril was also found more effective than losartan in reducing HPP (P=0.01) and 24-h APP (P=0.03) whereas no such a difference was detected using measurements of CPP. It was concluded that the antihypertensive drugs may differ in their effects not only on BP, but also on PP. HBP monitoring appears to be as reliable as 24-h ABP monitoring in detecting differences in the effect of drugs on both BP and PP. Clinic measurements seem to be the least reliable method, particularly in the detection of differences in PP.

Consensus Conference on Self-blood pressure measurement. Clinical applications and diagnosis.

The present study was aimed at reviewing the medical literature devoted to the clinical applications of self-blood pressure monitoring (SBPM) and at providing some recommendations regarding the use of SBPM for diagnostic purposes. The lack of reliability of conventional blood pressure (BP) measurement is largely related to the extreme variability of BP over time. SBPM provides a large number of readings and can be used to predict the results of repeated clinical measurements. The use of SBPM in the diagnosis of white coat hypertension can be proposed as a screening test: if it gives a positive result (a low home BP), it should be confirmed by ambulatory BP monitoring (ABPM). SBPM could improve patients' compliance with medication. Last, SBPM may be cost-effective for the management of hypertensive patients, by reducing costs of medication, number of clinic visits and costs of cardiovascular morbidity. Compared with ABPM, SBPM seems to have a less value for the initial diagnosis of hypertension and for predicting prognosis. In contrast, it should be of more value for the long term follow-up of patients with white coat hypertension and for the evaluation of treatment efficacy in patients with sustained hypertension. The use of SBPM in diabetic hypertensives, in pregnant women and in the elderly is encouraged, but needs further evaluation.