Treated hypertension and the white coat phenomenon: Office readings are inadequate measures of efficacy

Identification of patient-related, healthcare-related and knowledge-related factors associated with inadequate blood pressure control in outpatients: a cross-sectional study in Serbia

OBJECTIVES

To determine rate of blood pressure (BP) control and to analyse patient-related, medication-related and healthcare system-related factors associated with poor BP control in outpatients with hypertension (HT).

DESIGN

Cross-sectional study.

SETTING

Two study sites with different levels of healthcare (primary healthcare (PHC) and secondary level of healthcare (SHC)) in Vojvodina, Northern Serbia.

PARTICIPANTS

A total of 581 patients (response rate 96.8%) visiting their primary care physician between July 2019 and June 2020 filled out a pretested semistructured questionnaire and had a BP reading during their regular appointments.

PRIMARY AND SECONDARY OUTCOME MEASURES

Data on demographics, medication, BP control (target systolic BP≤140 mm Hg and∕ or diastolic BP≤90 mm Hg) and knowledge on HT was collected. Based on the median of knowledge score, patients were classified as having poor, average and adequate knowledge.

RESULTS

Majority of the respondents (74.9%) had poorly controlled BP and had HT longer than 10 years. Larger number of patients at PHC site was managed with monotherapy while at the SHC majority received three or more antihypertensive drugs. Respondents from SHC showed a significantly lower knowledge score (9, 2-15) compared with the respondents from PHC (11, 4-15, p=0.001). The share of respondents with adequate knowledge on HT was significantly higher in the group with good BP control (26% and 9.2%, respectively). In a multivariate regression analysis, factors associated with poor BP control were knowledge (B=-1.091; p<0001), number of drugs (B=0536; p<0001) and complications (B=0898; p=0004).

CONCLUSIONS

Poor BP control is common in outpatients in Serbia, irrespective of the availability of different levels of healthcare. Patients with poor knowledge on HT, with complications of HT and those with multiple antihypertensive drugs, were at particular risk of poor BP control. Our study could serve as a basis for targeted interventions to improve HT management.

Aldosterone-to-renin ratio is related to arterial stiffness when the screening criteria of primary aldosteronism are not met

Aldosterone-to-renin ratio (ARR) is a screening tool for primary aldosteronism (PA), but the significance of ARR when the PA criteria are not met remains largely unknown. In this cross-sectional study we investigated the association of ARR with haemodynamic variables in 545 normotensive and never-medicated hypertensive subjects (267 men, 278 women, age range 19-72 years) without suspicion of PA. Supine haemodynamic data was recorded using whole-body impedance cardiography and radial tonometric pulse wave analysis. In sex-adjusted quartiles of ARR, determined as serum aldosterone to plasma renin activity ratio, the mean values were 282, 504, 744 and 1467 pmol/µg of angiotensin I/h, respectively. The only difference in haemodynamic variables between the ARR quartiles was higher pulse wave velocity (PWV) in the highest quartile versus other quartiles (p = 0.004), while no differences in blood pressure (BP), heart rate, wave reflections, cardiac output or systemic vascular resistance were observed between the quartiles. In linear regression analysis with stepwise elimination, ARR was an independent explanatory factor for PWV (β = 0.146, p < 0.001, R2 of the model 0.634). In conclusion, ARR was directly and independently associated with large arterial stiffness in individuals without clinical suspicion of PA. Therefore, ARR could serve as a clinical marker of cardiovascular risk.Trial registration: ClinicalTrails.gov: NCT01742702.

Albuminuria and masked uncontrolled hypertension in chronic kidney disease

Background

Masked uncontrolled hypertension (MUCH) is associated with greater target organ damage such as left ventricular hypertrophy, increased arterial stiffness and albuminuria. Whether MUCH independently associates with greater cardiovascular end-organ damage or kidney damage is unclear. The objective of this study was to assess the strength of the relationship of MUCH (awake ambulatory blood pressure ≥135/85 mmHg and clinic blood pressure <140/90 mmHg) with target organ damage.

Methods

In a cross-sectional study at a veterans' administration medical center, clinically normotensive veterans without chronic kidney disease (CKD) (n = 29) and 287 patients with CKD and controlled hypertension (CH, n = 193), MUCH (n = 67) and uncontrolled hypertension (UCH, n = 27) had evaluation of target organ damage. Target organ damage was measured by echocardiography [left ventricular mass index (LVMI)], arterial ultrasonography [aortic pulse wave velocity (PWV)] and 24-h urine collection [albuminuria (urine albumin to creatinine ratio)] in all participants.

Results

Compared to that of controls, LVMI was higher by 21.8 g/m2 (CI, 4.0-39.7 g/m2) in CH, 27.9 (CI, 8-47.8) in MUCH and 39.5 (CI, 15.7-63.2) in UCH (P < 0.01 for group differences, P < 0.01 for linear trend). Although differences persisted after adjustment for age, sex and race, they lost significance after adjustments for cardiovascular risk factors and their treatment. Compared to that of controls, PWV was different among CH, MUCH and UCH (P = 0.04 for group differences, P = 0.02 for linear trend). However, differences lost significance after adjustments for age, sex and race. Compared to that of controls, log2 UACR was higher by 2.40 mg/mg (CI, 1.28-3.52) in CH, 4.94 (CI, 3.70-6.18) in MUCH and 6.01 (CI, 4.49-7.53) in UCH (P < 0.0001 for group difference, P < 0.0001 for linear trend). Differences persisted after adjustment for age, sex and race, cardiovascular risk factors and their treatment and cardiovascular disease (P < 0.0001 for group difference, P < 0.0001 for linear trend).

Conclusions

MUCH is more strongly related to albuminuria compared with cardiovascular damage as assessed by left ventricular mass and PWV. A graded and an independent relationship of blood pressure classification status with albuminuria is consistent with the hypothesis that renal mechanisms may be more important than cardiovascular disease in mediating the pathogenesis of MUCH.

A series of N-of-1 trials to assess the therapeutic interchangeability of two enalapril formulations in the treatment of hypertension in Addis Ababa, Ethiopia: study protocol for a randomized controlled trial

BACKGROUND

Hypertension is one of the leading causes of morbidity and mortality in Ethiopia. Treatment usually involves lifelong medication use. Enalapril is a common drug for the treatment of hypertension in Ethiopia. However, the drug is expensive and, therefore, there is limited capacity for people to afford the treatment. Locally produced Enalapril is a cost-effective solution to treat the disease. However, as local medicines regulation does not include bioequivalence tests on locally produced drugs, physicians and patients need assurance about the effectiveness and safety of local generics. Evidence on therapeutic equivalence is needed on these untested local drugs.

METHODS

This is a hospital-based, randomized, partially blinded, three-cycle crossover trial in single patients, comparing a locally produced version of enalapril with enalapril imported from Europe. Patients involved in this trial are not blinded, as there is no local facility to produce relatively small numbers of placebos or encapsulated drugs. To ensure blinding of study investigators and data analysts, study medications are prepared by an independent pharmacy unit using opaque medication packaging. The importance of maintaining blinding is also part of patient pre-trial education. Each N-of-1 trial will consist of three successive 14-day treatment pairs, each pair comprising 7 days of 5-20 mg local and 7 days of 5-20 mg imported enalapril taken once daily in the morning. The primary outcome will be the average difference in systolic blood pressure as measured by home blood pressure measurements.

DISCUSSION

The number of locally produced products, such as enalapril, being approved without proof of bioequivalence is dramatically increasing. By bridging the information gap on bioequivalence, the trial will give rigorous evidence on therapeutic equivalence of locally produced enalapril in the treatment of hypertension. If there is no difference, the hypothesized result, then patients can take the local medicine with confidence. This trial will also will determine whether aggregated N-of-1 studies are feasible to evaluate untested generic drugs in resource-limited countries where bioequivalence testing centers are unavailable.

TRIAL REGISTRATION NUMBER

Australian and New Zealand Clinical Trial Registry, ID: ACTRN12616001088437p . Registered on 12 August 2016.

Sources of inaccuracy in the measurement of adult patients' resting blood pressure in clinical settings: a systematic review

BACKGROUND

To interpret blood pressure (BP) data appropriately, healthcare providers need to be knowledgeable of the factors that can potentially impact the accuracy of BP measurement and contribute to variability between measurements.

METHODS

A systematic review of studies quantifying BP measurement inaccuracy. Medline and CINAHL databases were searched for empirical articles and systematic reviews published up to June 2015. Empirical articles were included if they reported a study that was relevant to the measurement of adult patients' resting BP at the upper arm in a clinical setting (e.g. ward or office); identified a specific source of inaccuracy; and quantified its effect. Reference lists and reviews were searched for additional articles.

RESULTS

A total of 328 empirical studies were included. They investigated 29 potential sources of inaccuracy, categorized as relating to the patient, device, procedure or observer. Significant directional effects were found for 27; however, for some, the effects were inconsistent in direction. Compared with true resting BP, significant effects of individual sources ranged from -23.6 to +33 mmHg SBP and -14 to +23 mmHg DBP.

CONCLUSION

A single BP value outside the expected range should be interpreted with caution and not taken as a definitive indicator of clinical deterioration. Where a measurement is abnormally high or low, further measurements should be taken and averaged. Wherever possible, BP values should be recorded graphically within ranges. This may reduce the impact of sources of inaccuracy and reduce the scope for misinterpretations based on small, likely erroneous or misleading, changes.

Comparative effectiveness of antihypertensive treatment for older children with primary hypertension: study protocol for a series of n-of-1 randomized trials

BACKGROUND

Children are increasingly being diagnosed with primary hypertension. The absence of comparative effectiveness research of antihypertensive medications in children has contributed to considerable differences in prescribing practices among physicians treating children with primary hypertension. Even if parallel-group trials had established a best overall choice for most of these children, the best medication for an individual may differ from the best overall medication.

METHODS/DESIGN

This project consists of a series of systematically administered n-of-1 trials among older children to verify the need for ongoing antihypertensive treatment and, if so, to identify the preferred single drug therapy from among the three major classes of drugs commonly used for primary hypertension (angiotensin-converting enzyme inhibitors, calcium channel blockers, and diuretics). We will determine whether one of these is the preferred therapy for the great majority of patients. The "preferred" therapy is the drug which produces normal ambulatory blood pressure, with the greatest reduction in blood pressure without unacceptable side effects. We will recruit 50 patients from the Houston Pediatric and Adolescent Hypertension Program clinic. For each patient, the three drugs will be prescribed in random order and each drug will be taken for 2 weeks. The effectiveness of each therapy will be measured with 24-h ambulatory blood pressure monitoring, and tolerability will be assessed using a side effect questionnaire. Participants will rotate through treatment periods, repeating drugs and adjusting doses until the preferred therapy is identified. In assessing whether one of the medications is most effective for the majority of subjects, the primary outcome will be the percentage of participants for whom each drug is selected as the preferred therapy. We hypothesize that no drug will be selected for the great majority of the subjects, a finding that would support consideration of clinical use of n-of-1 trials. Secondary analyses will explore whether patient characteristics predict which medication will be selected as a preferred drug.

DISCUSSION

This study will help optimize care of participating patients and provide evidence regarding the usefulness of n-of-1 trials in identifying appropriate treatment for children with hypertension and potentially other disorders.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02412761 (registered 4/8/2015).

Prevalence and Correlates of Prehypertension and Hypertension among Adults in Northeastern China: A Cross-Sectional Study

Background: Prehypertension is a category between normotension and hypertension that is becoming increasingly common in China. However, limited data are available on the prevalence and correlates of prehypertension in northeastern China. Methods: A cross-sectional study using stratified, clustered multistage, and random sampling methods was performed on 17,584 participants. Results: The prevalence of prehypertension and hypertension was 36.0% and 30.8% in northeastern China, respectively. As age increased, the prevalence of prehypertension in males declined (p-trend < 0.001), in parallel to an increase in the prevalence of hypertension (p-trend < 0.001). The prevalence of hypertension for females increased as age increased (p-trend < 0.001). Logistic regression analysis showed that age, gender, location, drinking, Body Mass Index (BMI), abdominal obesity, hypertriglyceridemia, and hypercholesterolemia correlated with prehypertension and hypertension (p-trend < 0.05). Conclusions: This study revealed a high prevalence of prehypertension and hypertension in an adult population of northeastern China and some correlates of prehypertension and hypertension.

Pro: Ambulatory blood pressure should be used in all patients on hemodialysis

In the adult population in general and among people with chronic kidney disease in particular, it is now well established that hypertension is a major driver of renal disease progression and cardiovascular morbidity and mortality. Although the contribution of hypertension to cardiovascular morbidity and mortality among patients on long-term dialysis continues to be debated, a major barrier to detect hypertension as a risk factor for cardiovascular events in these patients has been the inability to diagnose hypertension. Largely to blame has been the easy availability of pre-dialysis and post-dialysis blood pressure recordings in stark contrast to ambulatory blood pressure measurements in dialysis patients to accurately diagnose the presence or control of hypertension. It is increasingly becoming clear that out-of-office blood pressure recordings are superior to clinic recordings in making a diagnosis, assessing target organ damage, evaluating prognosis and managing patients with hypertension. In this debate, I have been asked to defend the position that ambulatory blood pressure recordings should be systematically applied to all patients on hemodialysis.

Rates, amounts, and determinants of ambulatory blood pressure monitoring claim reimbursements among Medicare beneficiaries

Ambulatory blood pressure monitoring (ABPM) can be used to identify white coat hypertension and guide hypertensive treatment. We determined the percentage of ABPM claims submitted between 2007 and 2010 that were reimbursed. Among 1970 Medicare beneficiaries with submitted claims, ABPM was reimbursed for 93.8% of claims that had an International Classification of Diseases, Ninth Revision, diagnosis code of 796.2 ("elevated blood pressure reading without diagnosis of hypertension") versus 28.5% of claims without this code. Among claims without an International Classification of Diseases, Ninth Revision, diagnosis code of 796.2 listed, those for the component (eg, recording, scanning analysis, physician review, reporting) versus full ABPM procedures and performed by institutional versus non-institutional providers were each more than two times as likely to be successfully reimbursed. Of the claims reimbursed, the median payment was $52.01 (25th-75th percentiles, $32.95-$64.98). In conclusion, educating providers on the ABPM claims reimbursement process and evaluation of Medicare reimbursement may increase the appropriate use of ABPM and improve patient care.

Identifying predictors of blood pressure control in the Lebanese population - a national, multicentric survey -- I-PREDICT

BACKGROUND

Blood Pressure (BP) is not well controlled and factors that predict BP control are not well identified in Lebanon. Improvement of hypertension management requires an understanding of patients' characteristics and factors associated with uncontrolled BP. This national, multicentric, observational prospective study was designed to determine the predictors of BP control in patients followed up to 6 months.

METHODS

I-PREDICT study was conducted on 988 patients with newly diagnosed or uncontrolled hypertension. Socio-demographic and clinical characteristics were analyzed. The level of agreement between doctors' perceptions on BP control status and JNC VII guidelines was analyzed.

RESULTS

The predictor associated with poor BP control was diabetes (OR = 0.17, CI = 0.10-0.28 at month-1; OR = 0.15, CI = 0.10-0.24 at month-6). The predictors associated with better BP control at month-6 were the early control of BP at month-1 (OR = 10.39, CI = 6.18-17.47) and combination therapy prescribed at baseline and month-1 (OR = 15.14, CI = 1.09-208.46, P = 0.04). In the sub-group of diabetes, the predictors that were associated with better BP control at 6 months were following diet at V1 (OR = 2.27, CI = 1.01 to 5.12) and BP control at V2 (OR = 7.34, CT = 3.83 to 14.07). The predictors that were associated with poor BP control at 6 months were middle economic class (OR = 0.036, CI = 0.16-0.94) and upper economic class (OR = 0.036; CI = 0.13-0.93).The rate of BP control was significantly higher at month 6 versus month 1 (67.52% vs 44.08%, P = 0.001). Additional analysis showed poor agreement between the doctors' perceptions on BP control status and the guidelines.

CONCLUSIONS

Reaching an early BP control and combination therapy were significant predictors of better BP control, whereas diabetes was a significant predictor of poor BP control. A poor agreement between JNC VII guidelines and clinical practice was observed. I-PREDICT study identified factors that can be targeted for improving BP control.

Closer look at white-coat hypertension

This review aims to clarify novel concepts regarding the clinical and laboratory aspects of white-coat hypertension (WCHT). Recent studies on the clinical and biological implications of WCHT were compared with existing knowledge. Studies were included if the WCHT patients were defined according to the 2013 European Society of Hypertension guidelines, i.e., an office blood pressure (BP) of ≥ 140/90 mmHg, a home BP of ≤ 135/85 mmHg, and a mean 24-h ambulatory BP of ≤ 130/80 mmHg. WCHT studies published since 2000 were selected, although a few studies performed before 2000 were used for comparative purposes. True WCHT was defined as normal ABPM and home BP readings, and partial WCHT was defined as an abnormality in one of these two readings. The reported prevalence of WCHT was 15%-45%. The incidence of WCHT tended to be higher in females and in non-smokers. Compared with normotensive (NT) patients, WCHT was associated with a higher left ventricular mass index, higher lipid levels, impaired fasting glucose, and decreased arterial compliance. The circadian rhythm in WCHT patients was more variable than in NT patient’s, with a higher pulse pressure and non-dipping characteristics. Compared with sustained hypertension patients, WCHT patients have a better 10-year prognosis; compared with NT patients, WCHT patients have a similar stroke risk, but receive more frequent drug treatment. There are conflicting results regarding WCHT and markers of endothelial damage, oxidative stress and inflammation, and the data imply that WCHT patients may have a worse prognosis. Nitric oxide levels are lower, and oxidative stress parameters are higher in WCHT patients than in NT patients, whereas the antioxidant capacity is lower in WCHT patients than in NT patients. Clinicians should be aware of the risk factors associated with WCHT and patients should be closely monitored especially to identify target organ damage and metabolic syndrome.