Prevalence, predictive factor, and clinical significance of white-coat hypertension and masked hypertension in Korean hypertensive patients

The 2022 focused update of the 2018 Korean Hypertension Society Guidelines for the management of hypertension

Hypertension is the leading cause of death in human being, which shows high prevalence and associated complications that increase the mortality and morbidity. Controlling blood pressure (BP) is very important because it is well known that lowering high BP effectively improves patients' prognosis. This review aims to provide a focused update of the 2018 Korean Hypertension Society Guidelines for the management of hypertension. The importance of ambulatory BP and home BP monitoring was further emphasized not only for the diagnosis but also for treatment target. By adopting corresponding BPs, the updated guideline recommended out-of-office BP targets for both standard and intensive treatment. Based on the consensus on corresponding BPs and Systolic Blood Pressure Intervention Trial (SPRINT) revisit, the updated guidelines recommended target BP in high-risk patients below 130/80 mmHg and it applies to hypertensive patients with three or more additional cardiovascular risk factors, one or more risk factors with diabetes, or hypertensive patients with subclinical organ damages, coronary or vascular diseases, heart failure, chronic kidney disease with proteinuria, and cerebral lacunar infarction. Cerebral infarction and chronic kidney disease are also high-risk factors for cardiovascular disease. However, due to lack of evidence, the target BP was generally determined at < 140/90 mmHg in patients with those conditions as well as in the elderly. Updated contents regarding the management of hypertension in special situations are also discussed.

Smoking and overweight associated with masked uncontrolled hypertension: a Hypertension Optimal Treatment (HOT) Sub-Study

PURPOSE

The Hypertension Optimal Treatment (HOT) Study investigated the relationship between target office diastolic blood pressure (BP) ≤80, ≤85 or ≤90 mmHg and cardiovascular morbidity and mortality in 18,790 patients aged 50-80 years. The home BP sub-study enrolled 926 patients and the aim was to clarify whether the separation into the BP target groups in the office prevailed in the out-of-office setting. The present study aimed to identify variables that characterised masked uncontrolled hypertension (MUCH) and white coat uncontrolled hypertension (WUCH).

MATERIAL AND METHODS

The sub-study participants took their home BP when office BP had been up titrated. The cut-off for normal or high BP was set to ≥135/85 mmHg at home and ≥140/90 mmHg in the office. We analysed data by using multivariate and stepwise multivariate logistic regression with home and office BP combinations as the dependent variables.

RESULTS

WUCH was associated with lower body mass index (BMI) (odds ratio (OR) 0.92, 95% confident intervals (CIs) 0.88-0.96, p < 0.001). MUCH was associated with smoking (OR 1.89, 95% CIs 1.25-2.86, p = 0.0025) and with lower baseline heart rate (OR 0.98, 95% CIs 0.97-0.99, p = 0.03) and higher BMI (OR 1.03, CIs 1.00-1.06, p = 0.04). MUCH remained associated with smoking (OR 2.76, 95% CIs 1.76-4.35, p < 0.0001) also when using ≥140/90 mmHg as the cut-off for both home and office BP. MUCH was also associated with higher BMI (OR 1.05, 95% CIs 1.01-1.09, p = 0.009) while WUCH was associated with lower BMI (OR 0.93, 95% CIs 0.90-0.97, p = 0.0005) when using ≥140/90 mmHg as a cut-off.

CONCLUSION

Our data support that 'reversed or masked' treated but uncontrolled hypertension (MUCH) is common and constitutes about 25% of treated hypertensive patients. This entity (MUCH) is rather strongly associated with current smoking and overweight while uncontrolled white coat (office) hypertension (WUCH) is associated with lower BMI.

Sex differences in masked hypertension: the Coronary Artery Risk Development in Young Adults study

OBJECTIVE

To evaluate the association of sex with masked hypertension, defined by out-of-clinic hypertension based on ambulatory blood pressure monitoring (ABPM) among adults without hypertension based on blood pressure (BP) measured in the clinic, after adjusting for potential confounders.

METHODS

We evaluated sex differences in the prevalence of masked hypertension and the difference between awake, or alternatively 24-h, ambulatory BP and clinic BP using multivariable adjusted models among 658 participants who underwent 24-h ABPM and had clinic SBP/DBP less than 140/90 mmHg during the Year 30 Exam of the Coronary Artery Risk Development in Young Adults study.

RESULTS

The mean age ± standard deviation (SD) of the participants was 54.8 ± 3.7 years, 58.4% were women, and 58.2% were black. The prevalence of any masked hypertension was 37.5% among women and 60.6% among men. In a model including adjustment for demographics, cardiovascular risk factors, antihypertensive medication, and clinic BP, the prevalence ratios (95% confidence intervals) comparing men versus women were 1.39 (1.18-1.63) for any masked hypertension, and 1.60 (1.28-1.99), 1.71 (1.36-2.15), and 1.40 (1.13-1.73) for masked awake, 24-h and asleep hypertension, respectively. In a fully adjusted model, the differences between mean awake ambulatory BP and clinic BP were 2.75 [standard error (SE) 0.92] mmHg higher for SBP and 3.61 (SE 0.58) mmHg higher for DBP among men compared with women.

CONCLUSION

The prevalence of masked hypertension on ABPM was high in both men and women. Male sex was an independent predictor of masked hypertension.

2018 Korean Society of Hypertension guidelines for the management of hypertension: part I-epidemiology of hypertension

The Korean Society of Hypertension guideline defines hypertension as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg, where the effectiveness of pharmacological treatment has been established. It is confirmed that higher blood pressure levels are associated with increased risk of cardiovascular disease and mortality also in the Korean population. About one third of Korean adults aged 30 years or older are estimated to have hypertension, and the prevalence of hypertension gradually increases as the age increases. The awareness, treatment, and control rates of hypertension are generally improving in Korea, but more efforts are required to increase awareness and treatment among younger patients with hypertension and to improve lifestyle modification compliance at all ages. More studies are required to determine the magnitude and impact of white coat hypertension and masked hypertension in the Korean population.

Magnitude of the Difference Between Clinic and Ambulatory Blood Pressures and Risk of Adverse Outcomes in Patients With Chronic Kidney Disease

Background Obtaining 24-hour ambulatory blood pressure ( BP ) is recommended for the detection of masked or white-coat hypertension. Our objective was to determine whether the magnitude of the difference between ambulatory and clinic BP s has prognostic implications. Methods and Results We included 610 participants of the AASK (African American Study of Kidney Disease and Hypertension) Cohort Study who had clinic and ambulatory BPs performed in close proximity in time. We used Cox models to determine the association between the absolute systolic BP ( SBP ) difference between clinic and awake ambulatory BPs (primary predictor) and death and end-stage renal disease. Of 610 AASK Cohort Study participants, 200 (32.8%) died during a median follow-up of 9.9 years; 178 (29.2%) developed end-stage renal disease. There was a U-shaped association between the clinic and ambulatory SBP difference with risk of death, but not end-stage renal disease. A 5- to <10-mm Hg higher clinic versus awake SBP (white-coat effect) was associated with a trend toward higher (adjusted) mortality risk (adjusted hazard ratio, 1.84; 95% CI, 0.94-3.56) compared with a 0- to <5-mm Hg clinic-awake SBP difference (reference group). A ≥10-mm Hg clinic-awake SBP difference was associated with even higher mortality risk (adjusted hazard ratio, 2.31; 95% CI, 1.27-4.22). A ≥-5-mm Hg clinic-awake SBP difference was also associated with higher mortality (adjusted hazard ratio, 1.82; 95% CI, 1.05-3.15) compared with the reference group. Conclusions A U-shaped association exists between the magnitude of the difference between clinic and ambulatory SBP and mortality. Higher clinic versus ambulatory BPs (as in white-coat effect) may be associated with higher risk of death in black patients with chronic kidney disease.

Diagnostic accuracy of manual office blood pressure measurement in ambulatory hypertensive patients in Korea

BACKGROUND/AIMS

Currently, office blood pressure (OBP) is the most widely used method of measuring blood pressure (BP) in daily clinical practice. However, data on the diagnostic accuracy of OBP in reference to ambulatory blood pressure (ABP) are scarce in Korea.

METHODS

In retrospective and prospective cohorts, manual OBP and ABP measurements were compared among ambulatory hypertensive patients. Hypertension was defined as systolic OBP ≥ 140 mmHg and/or diastolic OBP ≥ 90 mmHg, and systolic ABP ≥ 130 mmHg and/or diastolic ABP ≥ 80 mmHg.

RESULTS

In the retrospective cohort (n = 903), the mean OBP1 (before ABP measurement) was higher than ABP in both systolic (138 ± 17 mmHg vs. 123 ± 13 mmHg, p < 0.001) and diastolic (84 ± 12 mmHg vs. 78 ± 11 mmHg, p < 0.001) measurements. Interestingly, there was only a weak correlation between OBP and ABP (r² = 0.038, p < 0.001). The overall discordance rate of OBP compared to ABP, which is the reference method for measuring BP, was 43.9%. The prospective cohort (n = 57) showed similar results. In a subgroup analysis, male patients had higher false negative results (masked or under-treated hypertension) than did female patients (26.1% vs. 17.8%, p = 0.003), whereas female patients had a higher false positive rate (white-coat or over-treated hypertension) than did male patients (28.7% vs. 15.2%, p < 0.001).

CONCLUSIONS

The diagnostic accuracy of manual OBP is low in reference to ABP. Men and women have different patterns of discordance. These findings indicate that management of hypertensive patients with manual OBP measurements may be suboptimal and encourages the use of ABP in ambulatory hypertensive patients.

Decoding white coat hypertension

There is arguably no less understood or more intriguing problem in hypertension that the "white coat" condition, the standard concept of which is significantly blood pressure reading obtained by medical personnel of authoritative standing than that obtained by more junior and less authoritative personnel and by the patients themselves. Using hospital-initiated ambulatory blood pressure monitoring, the while effect manifests as initial and ending pressure elevations, and, in treated patients, a low daytime profile. The effect is essentially systolic. Pure diastolic white coat hypertension appears to be exceedingly rare. On the basis of the studies, we believe that the white coat phenomenon is a common, periodic, neuro-endocrine reflex conditioned by anticipation of having the blood pressure taken and the fear of what this measurement may indicate concerning future illness. It does not change with time, or with prolonged association with the physician, particularly with advancing years, it may be superimposed upon essential hypertension, and in patients receiving hypertensive medication, blunting of the nighttime dip, which occurs in about half the patients, may be a compensatory mechanisms, rather than an indication of cardiovascular risk. Rather than the blunted dip, the morning surge or the widened pulse pressure, cardiovascular risk appears to be related to elevation of the average night time pressure.

Which dialysis unit blood pressure is the most accurate for predicting home blood pressure in patients undergoing hemodialysis?

BACKGROUND/AIMS

We investigated which dialysis unit blood pressure (BP) is the most useful for predicting home BP in patients undergoing hemodialysis (HD).

METHODS

Patients undergoing HD who had been treated > 3 months were included in this study. Exclusion criteria were hospitalized patients with acute illness and changes in dry weight and anti-hypertensive drugs 2 weeks before the study. We used the dialysis unit BP recording data, such as pre-HD, intra-HD, post-HD, mean pre-HD, and post-HD (pre-post-HD), mean pre-HD, intra-HD, and post-HD (pre-intra-post-HD) BP. Home BP (the same period of dialysis unit BP) was monitored as a reference method during 2 weeks using the same automatic oscillometric device. Patients were asked to record their BP three times daily (wake up, between noon and 6:00 PM, and at bedtime).

RESULTS

Significant differences were detected between home systolic blood pressure (SBP) and pre-HD, post-HD, and intra-HD SBP (p = 0.003, p = 0.001, p = 0.016, respectively). In contrast, no differences were observed between home SBP and pre-intra-post-HD and pre-post-HD SBP (p = 0.235, p = 0.307, respectively). Areas under the receiver operating characteristic curve for pre-intra-post-HD and prepost-HD SBP with 2-week home BP as the reference standard were 0.812 and 0.801, respectively.

CONCLUSIONS

These results suggest that pre-intra-post-HD and pre-post-HD SBP had similar accuracy for predicting mean 2-week home SBP in HD patients. Therefore, pre-intra-post-HD and pre-post-HD SBP should be useful for predicting home SBP in HD patients if ambulatory or home BP measurements are unavailable.

Are increased oxidative stress and asymmetric dimethylarginine levels associated with masked hypertension?

OBJECTIVE

In this study, our aim was to determine total oxidative stress and asymmetric dimethylarginine (ADMA) levels in patients with masked hypertension (MHT) and to examine their association with blood pressure.

METHODS

Fifty patients diagnosed with MHT and 48 healthy volunteers without any known chronic diseases have been included in this study.

RESULTS

When compared to the control group, patients with MHT had higher levels of mean ADMA (p < 0.001), total oxidant status (TOS) (p < 0.001), and oxidative stress index (OSI) (p < 0.001), and a lower mean total antioxidant status (TAS) (p < 0.001) level. While a positive correlation was determined between the systolic blood pressure (SBP) and diastolic blood pressure (DBP) levels with ADMA, TOS, and OSI levels, a negative correlation was determined with the TAS level. During the stepwise multivariable logistic regression analysis, age (OR = 1.221; p = 0.003), body mass index (OR = 1.512; p = 0.005), low density lipoprotein (OR = 0.925; p = 0.016), ADMA (OR = 1.200; p = 0.002), and OSI (OR = 3.750; p = 0.002) levels were determined to be the predictors of MHT. During the linear regression analysis, it was determined that the independent risk factors of SBP and DBP are ADMA and OSI, and the independent risk factor of TOS, OSI, and ADMA is SBP. Our study found out that oxidative stress and ADMA levels of patients with MHT are higher than those of the control group. ADMA and OSI were determined to be predictors of MHT.

CONCLUSION

Based on these results, it could be said that oxidative stress, and therefore the ADMA level, could have an effect on the etiopathogenesis of MHT.

Prevalence of resistant hypertension and associated factors for blood pressure control status with optimal medical therapy using Korean ambulatory blood pressure monitoring registry data

Background

Resistant hypertension (RH) may be one of the cause of the plateau in improving the control rate in hypertension (HT) management. The misdiagnosis of RH by clinic blood pressure (BP) is important clinical problem. Aim of the study were to investigate the prevalence of RH by ambulatory blood pressure monitoring (ABPM) and the factor associated with control status of ambulatory BPs.

Methods

For 1230 subjects taking one or more antihypertensive medication (AHM) enrolled in the Korean Ambulatory Blood Pressure Monitoring (Kor-ABP) registry, the prevalence of RH was calculated which was defined as uncontrolled BP by three AHM classes including diuretic or BP in need of four or more AHM classes. The prevalence determined by clinic versus ambulatory BP was compared.

Results

The age was 59.3 ± 12.5 years, and 44.3 % were female (n = 1230). Among them 72 subjects were taking three AHM drugs including diuretics and 105 subjects were taking four or more AHM classes. With uncontrolled daytime ambulatory BP in 41 among 72 subjects, prevalence of RH was 11.9 % (146/1230). By using nighttime BP criteria, there was significant difference in the prevalence of RH for clinic versus nighttime BP (146/177 vs. 159/177, p = 0.0124). For control status of daytime BP, masked uncontrolled BP was 16.9 % and controlled BP with white-coat effect was 14.1 %. For nighttime BP control status, odd ratios for smoking (0.624), drinking (1.512), coronary artery disease (0.604), calcium antagonist (1.705), and loop diuretics (0.454) were all significant.

Conclusion

The prevalence itself was 11.9 % by daytime BP and it was significantly higher when using nighttime BP criteria. Control status of daytime BP was misclassified in 31.0 %. Smoking, drinking, coronary artery disease, calcium antagonist, and loop diuretics were associated with nighttime BP control status.

Discordance between ambulatory versus clinic blood pressure according to global cardiovascular risk group

BACKGROUND/AIMS

The detection of white coat hypertension (WCH), treated normalized hypertension, and masked hypertension (MH) is important to improve the effectiveness of hypertension management. However, whether global cardiovascular risk (GCR) profile has any effect on the discordance between ambulatory blood pressure (ABP) and clinic blood pressure (CBP) is unknown.

METHODS

Data from 1,916 subjects, taken from the Korean Multicenter Registry for ABP monitoring, were grouped according to diagnostic and therapeutic thresholds for CBP and ABP (140/90 and 135/85 mmHg, respectively). GCR was assessed using European Society of Hypertension 2007 guidelines.

RESULTS

The mean subject age was 54.1 ± 14.9 years, and 48.9% of patients were female. The discordancy rate between ABP and CBP in the untreated and treated patients was 32.5% and 26.5%, respectively (p = 0.02). The prevalence of WCH or treated normalized hypertension and MH was 14.4% and 16.0%, respectively. Discordance between ABP and CBP was lower in the very high added-risk group compared to the moderate added-risk group (odds ratio [OR], 0.649; 95% confidence interval [CI], 0.487 to 0.863; p = 0.003). The prevalence of WCH or treated normalized hypertension was also lower in the very high added-risk group (OR, 0.451; 95% CI, 0.311 to 0.655).

CONCLUSIONS

Discordance between ABP and CBP was observed more frequently in untreated subjects than in treated subjects, and less frequently in the very high added-risk group, which was due mainly to the lower prevalence of WCH or treated normalized hypertension.

2013 Korean Society of Hypertension guidelines for the management of hypertension: part I-epidemiology and diagnosis of hypertension

The standardized techniques of blood pressure measurement in the clinic are emphasized and the indications for ambulatory and/or home blood pressure monitoring are specified more broadly. The epidemiologic findings specific to Korean population related to blood pressure are reviewed. Cardiovascular risk of hypertensive patients are stratified based upon the data of a Korean population cohort study.

Ambulatory blood pressure measurement in the main cities of Cameroon: prevalence of masked and white coat hypertension, and influence of body mass index

Introduction

Identifying White Coat Hypertension (WCH) may avoid inappropriate commitment of individuals to lifelong and costly blood pressure (BP) lowering medications’. We assessed the prevalence and determinants of WCH in urban clinical settings in Cameroon.

Methods

Participants were a consecutive sample of adults, who underwent ambulatory BP measurements (ABPM) for the diagnosis of hypertension and evaluation of treatmentin three referral cardiac clinics in the cities of Yaounde and Douala, between January 2006 and July 2011. WCH was defined as an office-based systolic (or diastolic) BP ≥ 140(90) mmHg together with an average day time ambulatory systolic (and diastolic) BP < 135(85) mmHg.

Results

Of the 500 participants included, 188 (37.6%) were women, 230 (46%) were nonsmokers and 53 (10.6%) had diabetes mellitus. The mean age was 51.6±10.2years. The ABPM readings were higher in men than in women (p<0.05).The prevalence of WCH was 26.4% overall, 39.3% in women and22.4% in men (p=0.01).In multivariable analysis, body mass index was the only significant determinant of WCH (Odds ratio= 1.15(95% confidence intervals: 1.00-1.43), p<0.05).

Conclusion

The prevalence of WCH was high in our study population and was correlated only with BMI. Accurate measurement of BP and appropriate diagnosis of hypertension using ABPM in this setting may help limiting the consequences of over estimating hypertension severity on individuals, families and health systems.

Sex differences in primary hypertension

Men have higher blood pressure than women through much of life regardless of race and ethnicity. This is a robust and highly conserved sex difference that it is also observed across species including dogs, rats, mice and chickens and it is found in induced, genetic and transgenic animal models of hypertension. Not only do the differences between the ovarian and testicular hormonal milieu contribute to this sexual dimorphism in blood pressure, the sex chromosomes also play a role in and of themselves. This review primarily focuses on epidemiological studies of blood pressure in men and women and experimental models of hypertension in both sexes. Gaps in current knowledge regarding what underlie male-female differences in blood pressure control are discussed. Elucidating the mechanisms underlying sex differences in hypertension may lead to the development of anti-hypertensives tailored to one's sex and ultimately to improved therapeutic strategies for treating this disease and preventing its devastating consequences.

Frequency and related factors of masked hypertension at a worksite in Korea

Objectives

Masked hypertension is associated with metabolic risks and increased risk of cardiovascular disease. The purpose of this study was to identify the frequency of and risk factors of masked hypertension in Korean workers.

Methods

The study was conducted among 121 employees at a hotel in Gyeongju, Korea, from December 2008 to February 2009. We measured blood pressure (BP) both in the clinic and using 24-hour ambulatory BP monitors for all subjects. Hypertension was defined independently by both methods, and subjects were classified into four groups: true normotension, masked hypertension, white coat hypertension, and sustained hypertension.

Results

The frequency of masked hypertension in our study group was 25.6%. Compared with true normotension, the factors related to masked hypertension were male gender (odds ratio [OR], 10.7; 95% confidence interval [CI], 1.41 to 81.09), aging one year (OR, 0.88; 95% CI, 0.78 to 0.99), clinic BP 120-129/80-84 mmHg (OR, 8.42; 95% CI, 1.51 to 46.82), clinic BP 130-139 / 85-89 mmHg (OR, 12.14; 95% CI, 1.80 to 81.85), smoking (OR, 5.51; 95% CI, 1.15 to 26.54), and increase of total cholesterol 1 mg / dL (OR, 1.05; 95% CI, 1.02 to 1.08). In males only, these factors were clinic BP 120-129 / 80-84 mmHg (OR, 15.07; 95% CI, 1.55 to 146.19), clinic BP 130-139 / 85-89 mmHg (OR, 17.16; 95% CI, 1.56 to 189.45), smoking (OR, 11.61; 95% CI, 1.52 to 88.62), and increase of total cholesterol 1 mg/dL (OR, 1.05; 95% CI, 1.01 to 1.09).

Conclusions

The frequency of masked hypertension was high in our study sample. Detection and management of masked hypertension, a known strong predictor of cardiovascular risk, could improve prognosis for at-risk populations.

Relationship of self-reported alcohol consumption to ambulatory blood pressure in a sample of healthy adults

BACKGROUND

Habitual alcohol consumption has shown positive associations with office blood pressure (BP). Less well established, however, is alcohol consumption's relationship to various measures of ambulatory BP (ABP) in healthy, normotensive persons.

METHODS

We investigated alcohol consumption's relationship to mean ABP, ABP variability, and the ABP arterial stiffness index in a sample of nonsmoking adults who were free of hypertension and cardiovascular disease (CVD; n = 157). Total alcohol consumption, intake of specific alcoholic beverages, and binge drinking were assessed by self-report. ABP was measured every 30 min for 24 h.

RESULTS

In multivariable-adjusted linear regression models, higher levels of total weekly alcohol consumption were associated with higher ABP. For those consuming 0, 1-2, and 3 or more alcoholic drinks per week, mean 24-h systolic ABP values were 112.2, 115.2, and 116.6 mm Hg, respectively (P = 0.05), and mean 24-h diastolic ABP values were 70.6, 71.9, and 74.2 mm Hg, respectively (P = 0.02). Beer and liquor consumption showed stronger positive associations with ABP than did wine consumption. Among nonbinge drinkers and binge drinkers, mean 24-h systolic ABP values were 113.3 and 118.6 mm Hg, respectively (P = 0.04) and mean 24-h diastolic ABP values were 71.3 and 75.0 mm Hg, respectively (P = 0.04). Alcohol consumption was not significantly related to ABP variability or the ABP arterial stiffness index.

CONCLUSION

Total habitual alcohol consumption, consumption of specific alcoholic drinks, and binge drinking are associated with higher mean ABP in healthy, normotensive adults.