Willem J. Verberk

Self-measurement of blood pressure at home reduces the need for antihypertensive drugs: a randomized, controlled trial.

It is still uncertain whether one can safely base treatment decisions on self-measurement of blood pressure. In the present study, we investigated whether antihypertensive treatment based on self-measurement of blood pressure leads to the use of less medication without the loss of blood pressure control. We randomly assigned 430 hypertensive patients to receive treatment either on the basis of self-measured pressures (n=216) or office pressures (OPs; n=214). During 1-year follow-up, blood pressure was measured by office measurement (10 visits), ambulatory monitoring (start and end), and self-measurement (8 times, self-pressure group only). In addition, drug use, associated costs, and degree of target organ damage (echocardiography and microalbuminuria) were assessed. The self-pressure group used less medication than the OP group (1.47 versus 2.48 drug steps; P<0.001) with lower costs (

Prevalence, Causes, and Consequences of Masked Hypertension: A Meta-analysis

3222 versus

Blood Pressure Measurement Method and Inter-Arm Differences: A Meta-Analysis

4420 per 100 patients per month; P<0.001) but without significant differences in systolic and diastolic OP values (1.6/1.0 mm Hg; P=0.25/0.20), in changes in left ventricular mass index (-6.5 g/m(2) versus -5.6 g/m(2); P=0.72), or in median urinary microalbumin concentration (-1.7 versus -1.5 mg per 24 hours; P=0.87). Nevertheless, 24-hour ambulatory blood pressure values at the end of the trial were higher in the self-pressure than in the OP group: 125.9 versus 123.8 mm Hg (P<0.05) for systolic and 77.2 versus 76.1 mm Hg (P<0.05) for diastolic blood pressure. These data show that self-measurement leads to less medication use than office blood pressure measurement without leading to significant differences in OP values or target organ damage. Ambulatory values, however, remain slightly elevated for the self-pressure group.

The optimal scheme of self blood pressure measurement as determined from ambulatory blood pressure recordings

BACKGROUND Masked hypertension (MH) is a relatively newly detected condition of which little is known. More information about MH may help to improve overall antihypertensive health care. We aimed to investigate the prevalence, potential causes, and associated consequences of MH. METHODS We searched published literature using MEDLINE, EMBASE, and the Cochrane database completed with references cited in reviews and original study articles. We restricted our research to articles written in the English, German, French, and Spanish language. Studies were included only when the prevalence of MH was reported, office blood pressure (BP) values were given, and methods of BP measurements were described in detail. All data were extracted independently by two readers with a standardized protocol and data-collection form. RESULTS The prevalence of MH averaged 16.8% (95% confidence interval 13.0-20.5%). The MH prevalence was 7% for children and 19% for adults. MH prevalences did not differ significantly when determined with self or ambulatory BP measurement (21.1% vs. 16.8%; P = 0.42). Subjects with MH had significantly higher left ventricular mass index (LVMI) values than normotensives (110 vs. 98 g/m2; P < 0.01) but similar values as sustained hypertensives (109 g/m2). In addition, patients with MH were more often smokers than normotensives (mean difference 18%; P < 0.03). CONCLUSIONS MH strikes about a quarter of the patients who were initially classified as normotensives (based on office BP measurements) and of treated hypertensives. Patients with MH seem to have a similar cardiovascular risk as sustained hypertensives but they may remain undetected. The presence of MH seems to be a matter of a coincidently low office BP value not related to certain subject characteristics although the chance of its presence may be increased by smoking and antihypertensive treatment.

Assessing Medication Adherence Simultaneously by Electronic Monitoring and Pill Count in Patients With Mild-to-Moderate Hypertension

BACKGROUND Screening for inter-arm difference (IAD) of blood pressure (BP) at each first visit is recommended by numerous guidelines whereas it is unclear whether the method by which IAD is measured has significant influence on the IAD value. METHODS A systematic review is made of the studies reporting on double-arm measurements and the association of IAD with procedure characteristics (Medline/PubMed, Embase, and Cochrane Library). RESULTS The mean absolute IAD was 5.4 ± 1.7 and 3.6 ± 1.2 mm Hg for systolic and diastolic BP, respectively. Of all subjects 14% had a systolic IAD ≥10 mm Hg, 4% a systolic IAD ≥20 mm Hg, and 7% a diastolic IAD ≥10 mm Hg. The relative risk (RR) of obtaining a systolic IAD ≥10 and 20 mm Hg and a diastolic IAD ≥10 mm Hg is higher when measuring sequentially instead of simultaneously (2.2 (95% CI: 1.4-3.6), P < 0.01; 4.8 (95% CI: 1.1-21.9), P < 0.05 and 2.5 (95% CI: 1.0-6.3) P < 0.05, respectively), when using a manual instead of an automated device (2.1 (95% CI: 1.1-3.9), P < 0.05; 4.4 (95% CI: 1.8-10.8), P < 0.01 and 3.7 (95% CI: 1.6-8.6), P < 0.01, respectively) and when performing only one BP measurement instead of multiple (2.0 (95% CI: 1.1-3.8), P < 0.05; 4.3 (95% CI: 1.6-11.4), P < 0.01 and 4.4 (95% CI: 1.7-11.4), P < 0.01, respectively). CONCLUSION Screening for IAD of BP is important but the measurement methodology has a major influence on IAD results. To prevent overestimation and observer bias IAD should be assessed simultaneously at both arms, with one or two automatic devices and multiple readings should be taken.

Telecare is a valuable tool for hypertension management, a systematic review and meta-analysis

Objective To determine how many self-measurements of blood pressure (BP) should be taken at home in order to obtain a reliable estimate of a patients BP. Design Participants performed self blood pressure measurement (SBPM) for 7 days (triplicate morning and evening readings). In all of them, office blood pressure (three consecutive readings) and 24-h ambulatory blood pressure were obtained as well. Average SBPM values, obtained from several combinations of readings, were correlated with the results of ambulatory blood pressure measurement (ABPM). In addition, we assessed whether certain patient characteristics would influence such correlations. Setting Patients were recruited at hospital or general practice. Patients A total of 216 untreated hypertensive patients. Results The average SBPM value calculated from day 3 to day 7, omitting the first measurement of each morning and evening session, gave the best correlation with 24-h ABPM (r = 0.70). However, similar results were obtained from a SBPM value averaged from day 3 until 5 without the first measurement of each triplicate session. Overall, younger patients had significantly better correlations than older ones. Women had significantly better correlations with ABPM than men for systolic morning and daytime SBPM, whereas men had significantly better correlations for daytime and evening diastolic SBPM (P < 0.001). In addition, all correlations increased with lower systolic office blood pressure measurement (OBPM) values. Conclusions A minimum number of 5 days of measurement is recommended to obtain a reliable estimate of a patients usual BP. On each day, three consecutive morning and evening measurements should be performed. For calculating the average SBPM, the first 2 days and the first measurement of each triplicate measurements should be discarded. Moreover, patient characteristics may have an impact on the number of necessary self-measurements. However, because adhering to these recommendations will make SBPM a time-consuming procedure, this type of measurement should be performed only when a decision about starting or changing antihypertensive therapy is needed or in the case of special patient groups.

Participation in a Clinical Trial Enhances Adherence and Persistence to Treatment A Retrospective Cohort Study

BACKGROUND Poor adherence to antihypertensive medication is one of the major problems in the treatment of hypertension. Electronic monitoring is currently considered to be the gold standard for assessing adherence, but it may trigger patients to open the pill bottle without taking medication or to take out more than prescribed. In adjunct to electronic monitoring, pill count could be a valuable tool for exploring adherence patterns, and their effects on blood pressure reduction. METHODS Among a total of 228 patients with mild-to-moderate hypertension, adherence to treatment was measured by means of both the Medication Event Monitoring System (MEMS) and pill count. Patients were followed-up for seven visits over a period of 1 year. At each visit to the physicians office, patients adherence was assessed by both methods. RESULTS Adherence is defined as the percentage of days with correct dosing; median adherence according to MEMS was lower than median adherence according to pill count (91.6 vs. 96.1; P < 0.001). Both methods agreed in defining patients as adherent in 107 (47%) and nonadherent in 33 (14%) patients. Thirty-one (14%) patients were adherent only by MEMS and 59 (25%) patients only by pill count. At the end of the study, patients in the four categories reached comparable blood pressure values and reductions. CONCLUSIONS Pill count could be a useful adjunct to electronic monitoring in assessing adherence patterns. Although deviant intake behavior occurred frequently, the effect on achieved blood pressure and blood pressure reduction was not remarkable.

Automated oscillometric determination of the ankle-brachial index: a systematic review and meta-analysis

There is an increasing interest for using telecare(TC) in the management of hypertension. A systematic review to the use of blood pressure (BP) measurement in TC has been performed (Medline/PubMed, Embase, and Cochrane Library), selecting randomized clinical trials that compared TC with usual care (UC) for hypertension management (treatment and/or coaching). Nine randomized clinical trials were selected (n=2501, 61.4±0.6 years, 42±2.7% males). Overall there was a significant larger decrease in the TC group than in the UC group for systolic (5.2±1.5 mmHg; P<0.001) and diastolic BP (2.1±0.8 mmHg; P<0.01). When studies were separated for antihypertensive treatment modification during the study (yes or no), systolic BP decrease difference between the TC and UC groups (&Dgr;TC-&Dgr;UC) tended to be significantly lower (5.1±2.9 mmHg lower) with treatment modification compared with nontreatment modification in which the &Dgr;TC-&Dgr;UC was 8.6±2.4 mmHg, P=0.07. TC led to a greater decrease in systolic and diastolic BP than UC. The differences between TC and UC for systolic BP tend to become larger when no treatment modification is applied. TC seems a valuable tool for hypertension management.

Effect of self-measurement of blood pressure on adherence to treatment in patients with mild-to-moderate hypertension.

Poor adherence to treatment is one of the major determinants of an uncontrolled blood pressure. Participation in a clinical trial may increase patients adherence to treatment. This prompted us to investigate adherence and persistence profiles in patients with hypertension who had participated in a clinical trial, by collecting pharmacy refill data before, during, and after participation in the trial. Pharmacy refill data of 182 patients with hypertension who participated in the Home Versus Office Blood Pressure Measurements: Reduction of Unnecessary Treatment Study between 2001 and 2005 were obtained from 1999 until 2010. Refill adherence to treatment was compared for the periods before, during, and after this trial. Persistence to medication was investigated for the period after termination of the trial. Refill data were available for 22 600 prescriptions. Participation into the trial significantly increased refill adherence, from 90.6% to 95.6% (P<0.001). After the trial period, refill adherence decreased again to 91.8% (P<0.001), which did not differ from the adherence before the start of the trial (P=0.45). Except for adherence to trial medication, adherence to nontrial-related drugs also increased as a consequence of trial participation, from 77.6% to 89.6% (P<0.001). After termination of the trial, median persistence was 1424 days. Participants classified as adherent (adherence: >90%) were less likely to discontinue treatment compared with nonadherent participants (odds ratio: 0.66 [95% CI: 0.45 to 0.98]). Participation in a clinical trial significantly increases adherence to both trial-related and nontrial-related treatment, suggesting that participants in a trial are more involved with their conditions and treatments.

Prevalence of the white-coat effect at multiple visits before and during treatment

Measurement of the ankle-brachial index (ABI) using a Doppler device is widely used to identify subjects with peripheral artery disease (PAD), and those who are at high risk of cardiovascular disease. This paper presents a systematic review (Medline/PubMed, Embase and Cochrane) and meta-analysis of studies assessing the usefulness of automated oscillometric devices for ABI estimation and PAD detection compared with the conventional Doppler method. A total of 25 studies including 4186 subjects were analyzed. A random-effects model analysis showed that the average oscillometric ABI was similar to the Doppler ABI (mean difference±s.e. 0.020±0.018, P=0.3) but that the absolute differences were significant (0.048±0.009, P<0.01). The pooled correlation coefficient (r) between the oscillometric and Doppler ABI was 0.71±0.05. Simultaneous arm–leg measurements resulted in a smaller difference between the average oscillometric ABI value and the average Doppler ABI value than did sequential measurements (−0.012±0.022 vs. 0.040±0.026, respectively, P<0.01). The average sensitivity and specificity of the oscillometric ABI estimation in PAD diagnosis was 69±6% and 96±1%, respectively (with Doppler ABI taken as the reference). These data suggest that an automated ABI measurement obtained by oscillometric blood pressure monitors is a reliable and practical alternative to the conventional Doppler measurement for the detection of PAD. To increase the sensitivity of the PAD diagnosis based on an oscillometric ABI, a higher threshold of 1.0 might be preferable.