Masked hypertension: evaluation, prognosis, and treatment

Unique characteristics of Asians with hypertension: what is known and what can be done?

Hypertension remains the leading modifiable risk factor for cardiovascular disease worldwide. Over the past 30 years, the prevalence of hypertension has been increasing in East and Southeast Asia to a greater extent as compared with other Western countries. Asians with hypertension have unique characteristics. This can be attributed to increased impact of obesity on Asians with hypertension, excessive salt intake and increased salt sensitivity, loss of diurnal rhythm in blood pressure and primary aldosteronism. The impact of hypertension on cardiovascular (particularly strokes) and chronic kidney disease is greater in Asians. These unique characteristics underpinned by the diverse socioeconomic backgrounds pose its own challenges in the diagnosis and management of hypertension in Asia.

Interpretation of Ambulatory Blood Pressure Monitoring for Risk Stratification in Hypertensive Patients: The 'Ambulatory Does Prediction Valid (ADPV)' Approach

Several outcome-based prospective investigations have provided solid data which support the prognostic value of 24 h ambulatory blood pressure over and beyond cardiovascular traditional risk factors. Average 24 h, daytime, and nighttime blood pressures are the principal components of the ambulatory blood pressure profile that have improved cardiovascular risk stratification beyond traditional risk factors. Furthermore, several additional ambulatory blood pressure measures have been investigated. The correct interpretation in clinical practice of ambulatory blood pressure monitoring needs a standardization of methods. Several algorithms for its clinical use have been proposed. Implementation of the results of ambulatory blood pressure monitoring in the management of individual subjects with the aim of improving risk stratification is challenging. We suggest that clinicians should focus attention on ambulatory blood pressure components which have been proven to act as the main independent predictors of outcome (average 24 h, daytime, and nighttime blood pressure, pulse pressure, dipping status, BP variability).

Prevalence and characteristics of isolated nocturnal hypertension in the general population

BACKGROUND/AIMS

Ascertaining the prevalence of isolated nocturnal hypertension (INHT) in the general population and identifying the characteristics of patients with INHT may be important to determine patients who should receive 24- hour ambulatory blood pressure (BP) measurements. This study aimed to evaluate the prevalence and characteristics of INHT in the general population.

METHODS

Of 1,128 participants (aged 20 to 70 years), we analyzed 823 who had valid 24-hour ambulatory BP measurements and were not on antihypertensive drug treatment.

RESULTS

The prevalence of INHT in the study was 22.8%. Individuals with INHT had a higher office, 24-hour, and daytime and nighttime ambulatory systolic and diastolic BPs compared to individuals with sustained day-night normotension. INHT was more prevalent in individuals with masked hypertension (MH) than in those with sustained hypertension (59.8% vs. 15.6%, p < 0.001). Among individuals with INHT, 92.6% had MH. Among individuals with office BP-based prehypertension, 34.5% had both INHT and MH. The prevalence of INHT was highest in individuals with office BP-based prehypertension. INHT was an independent determinant of MH after adjustment for age, sex, body mass index, diabetes, low-density-lipoprotein cholesterol, 24-hour systolic and diastolic BP, systolic and diastolic BP dipping, and systolic and diastolic BP non-dipping.

CONCLUSION

The present study showed that INHT is not uncommon and is a major determinant of MH. Our findings strongly suggest the use of 24-hour ambulatory BP measurement for individuals within the prehypertension range of office BP owing to the high prevalence of INHT and MH in this population.

Frequency of masked hypertension in patients with nonfunctioning adrenal incidentalomas with normal and high normal blood pressure

OBJECTIVES

Nonfunctioning adrenal incidentalomas (NFAIs) are associated with increased cardiovascular risk, but the frequency of masked hypertension (MH) is uncertain in these patients. This study aimed to evaluate the prevalence of MH by ambulatory blood pressure monitoring in patients with NFAIs.

METHODS

The study included a total of 85 individuals: 43 patients with NFAIs and 42 controls of similar age, gender, BMI, smoking, and diabetes. The office BP and ABPM parameters of the NFAI and controls were measured. Biochemical, hormonal, and radiological data were obtained retrospectively in the NFAI group.

RESULTS

There were no statistically significant difference between the NFAI and control groups in relation to the office SBP (134.4 ± 37.2 mmHg vs 133.1 ± 35.8 mmHg, p = 0.273) and office DBP (87.4 ± 14.5 mmHg vs 86.8 ± 13.7 mmHg, p = 0.318). Besides, normal (28% vs 28.6%, p = 0.176) and high normal blood pressure (72% vs 71.4%, p = 0.332) rates were similar. The prevalence of MH was significantly higher in patients with NFAI than in controls (25.5% vs 9.5%, p = 0.037). MH was significantly associated with diabetes odds ratio (OR) = 2.07, p = 0.044, office SBP (OR = 1.41, p = 0.046), smoking (OR = 1.46, p = 0.031), BMI (OR = 1.17, p = 0.037), and morning cortisol (OR = 1.21, p = 0.039).

CONCLUSION

The prevalence of MH in the NFAI patient's was higher than in the control group. Patients with NFAI with high normal blood pressure should be evaluated for MH.

The 2020 International Society of Hypertension global hypertension practice guidelines - key messages and clinical considerations

The International Society of Hypertension (ISH) has recently developed practice guidelines for the management of hypertension in adults aged ≥18 years. Conceptually, the 2020 ISH Guidelines are closer to the 2018 ESC/ESH Guidelines rather than to the 2017 ACC/AHA Guidelines. The ISH Guidelines have two distinctive features when compared with the 2018 European Society of Cardiology/European Society of Hypertension (ESC/ESH) Guidelines and the 2017 American College of Cardiology/American Heart Association (ACC/AHA) Guidelines. First, they are written in a concise and easy-to-read style; second, they focuses on practical issues related to the management of hypertension in 'high-income' as well as in 'low-income' countries, where there is limited access to resources for the diagnosis and treatment of hypertension. In our opinion, the 2020 ISH Guidelines share with the 2018 ESC/ESH Guidelines an important limitation which may impair the retention of these key aspects of Guidelines by physicians, with consequent difficult adoption in clinical practice. It consists in the definition of several blood pressure targets in relation to age, target organ damage and concomitant disease. We believe that results of randomized clinical trials and meta-analysis do not support the recommendation of differential BP targets, as well as of rigid 'safety boundaries'. This review critically examines similarities and differences across the three major Hypertension Guidelines, which include the definition of hypertension, drug treatment, and blood pressure targets, with emphasis on key messages relevant for clinical practice.

A comparative meta-analysis of prospective observational studies on masked hypertension and masked uncontrolled hypertension defined by ambulatory and home blood pressure

BACKGROUND

In a comparative meta-analysis, we investigated the prognostic value of masked hypertension and masked uncontrolled hypertension defined by ambulatory or home blood pressure (BP) monitoring.

METHODS

We searched English literature published till 2 September 2018 to identify prospective observational studies. Masked hypertension was defined as a normal clinic BP (<140/90 mmHg) in the presence of an elevated 24 h, daytime or night-time ambulatory or home BP. Clinical outcomes included all-cause and cardiovascular mortality, and fatal and nonfatal cardiovascular, stroke, cardiac, coronary and renal disease events.

RESULTS

In total, 21 studies (n = 130 318) were included. Overall, compared with normotensive participants, masked hypertensive patients had a 5.7/2.9 mmHg higher clinic BP and 18.7/9.8 mmHg higher out-of-office BP. The pooled risk ratio for masked hypertension versus normotension was 1.67 (95% confidence interval, 1.32-2.13) and 2.19 (1.72-2.78) for all-cause (eight studies) and cardiovascular mortality (three studies), respectively, and 1.71 (1.53-1.91), 1.95 (1.36-2.80), 1.76 (1.33-2.33), 1.62 (0.27-9.60), 3.85 (2.03-7.31) for fatal and nonfatal cardiovascular (15 studies), stroke (two studies), cardiac (two studies), coronary (two studies) and renal disease events (two studies), respectively. Risk ratios for all-cause mortality (1.78 versus 1.40, P = 0.16) and fatal and nonfatal cardiovascular events (1.81 versus 1.61, P = 0.29) were similar between studies on ambulatory and home BP monitoring in the overall analyses. The analyses in subgroups according to treatment status (untreated, treated or mixed) and sampling approach (population or referred patients) were confirmatory.

CONCLUSION

Masked hypertension and masked uncontrolled hypertension were associated with unfavorable clinical outcomes, regardless of the out-of-office BP monitoring techniques.

Blood Pressure Measurement and Treatment Decisions

White-coat and masked hypertension are important hypertension phenotypes. Out-of-office blood pressure measurement is essential for the accurate diagnosis and monitoring of these conditions. This review summarizes literature related to the detection and diagnosis, prevalence, epidemiology, prognosis, and treatment of white-coat and masked hypertension. Cardiovascular risk in white-coat hypertension appears to be dependent on the presence of coexisting risk factors, whereas patients with masked hypertension are at increased risk of target organ damage and cardiovascular events. There is an unmet need for robust data to support recommendations around the use of antihypertensive treatment for the management of white-coat and masked hypertension.

Pressure modification or humidification for improving usage of continuous positive airway pressure machines in adults with obstructive sleep apnoea

BACKGROUND

Obstructive sleep apnoea (OSA) is the repetitive closure of the upper airway during sleep. This results in disturbed sleep and excessive daytime sleepiness. It is a risk factor for long-term cardiovascular morbidity. Continuous positive airway pressure (CPAP) machines can be applied during sleep. They deliver air pressure by a nasal or oronasal mask to prevent the airway from closing, reducing sleep disturbance and improving sleep quality. Some people find them difficult to tolerate because of high pressure levels and other symptoms such as a dry mouth. Switching to machines that vary the level of air pressure required to reduce sleep disturbance could increase comfort and promote more regular use. Humidification devices humidify the air that is delivered to the upper airway through the CPAP circuit. Humidification may reduce dryness of the throat and mouth and thus improve CPAP tolerability. This updated Cochrane Review looks at modifying the delivery of positive pressure and humidification on machine usage and other clinical outcomes in OSA.

OBJECTIVES

To determine the effects of positive pressure modification or humidification on increasing CPAP machine usage in adults with OSA.

SEARCH METHODS

We searched Cochrane Airways Specialised Register and clinical trials registries on 15 October 2018.

SELECTION CRITERIA

Randomised parallel group or cross-over trials in adults with OSA. We included studies that compared automatically adjusting CPAP (auto-CPAP), bilevel positive airway pressure (bi-PAP), CPAP with expiratory pressure relief (CPAPexp), heated humidification plus fixed CPAP, automatically adjusting CPAP with expiratory pressure relief, Bi-PAP with expiratory pressure relief, auto bi-PAP and CPAPexp with wakefulness detection with fixed pressure setting.

DATA COLLECTION AND ANALYSIS

We used standard methods expected by Cochrane. We assessed the certainty of evidence using GRADE for the outcomes of machine usage, symptoms (measured by the Epworth Sleepiness Scale (ESS)), Apnoea Hypopnoea Index (AHI), quality of life measured by Functional Outcomes of Sleep Questionnaire (FOSQ), blood pressure, withdrawals and adverse events (e.g. nasal blockage or mask intolerance). The main comparison of interest in the review is auto-CPAP versus fixed CPAP.

MAIN RESULTS

We included 64 studies (3922 participants, 75% male). The main comparison of auto-CPAP with fixed CPAP is based on 36 studies with 2135 participants from Europe, USA, Hong Kong and Australia. The majority of studies recruited participants who were recently diagnosed with OSA and had not used CPAP previously. They had excessive sleepiness (ESS: 13), severe sleep disturbance (AHI ranged from 22 to 59), and average body mass index (BMI) of 35 kg/m2. Interventions were delivered at home and the duration of most studies was 12 weeks or less. We judged that studies at high or unclear risk of bias likely influenced the effect of auto-CPAP on machine usage, symptoms, quality of life and tolerability, but not for other outcomes. Primary outcome Compared with average usage of about five hours per night with fixed CPAP, people probably use auto-CPAP for 13 minutes longer per night at about six weeks (mean difference (MD) 0.21 hours/night, 95% confidence interval (CI) 0.11 to 0.31; 31 studies, 1452 participants; moderate-certainty evidence). We do not have enough data to determine whether auto-CPAP increases the number of people who use machines for more than four hours per night compared with fixed CPAP (odds ratio (OR) 1.16, 95% CI 0.75 to 1.81; 2 studies, 346 participants; low-certainty evidence). Secondary outcomes Auto-CPAP probably reduces daytime sleepiness compared with fixed CPAP at about six weeks by a small amount (MD -0.44 ESS units, 95% CI -0.72 to -0.16; 25 studies, 1285 participants; moderate-certainty evidence). AHI is slightly higher with auto-CPAP than with fixed CPAP (MD 0.48 events per hour, 95% CI 0.16 to 0.80; 26 studies, 1256 participants; high-certainty evidence), although it fell with both machine types from baseline values in the studies. Ten per cent of people in auto-CPAP and 11% in the fixed CPAP arms withdrew from the studies (OR 0.90, 95% CI 0.64 to 1.27; moderate-certainty evidence). Auto-CPAP and fixed CPAP may have similar effects on quality of life, as measured by the FOSQ but more evidence is needed to be confident in this result (MD 0.12, 95% CI -0.21 to 0.46; 3 studies, 352 participants; low-certainty evidence). Two studies (353 participants) provided data on clinic-measured blood pressure. Auto-CPAP may be slightly less effective at reducing diastolic blood pressure compared to fixed CPAP (MD 2.92 mmHg, 95% CI 1.06 to 4.77 mmHg; low-certainty evidence). The two modalities of CPAP probably do not differ in their effects on systolic blood pressure (MD 1.87 mmHg, 95% CI -1.08 to 4.82; moderate-certainty evidence). Nine studies (574 participants) provided information on adverse events such as nasal blockage, dry mouth, tolerance of treatment pressure and mask leak. They used different scales to capture these outcomes and due to variation in the direction and size of effect between the studies, the comparative effects on tolerability outcomes are uncertain (very low-certainty evidence).  The evidence base for other interventions is smaller, and does not provide sufficient information to determine whether there are important differences between pressure modification strategies and fixed CPAP on machine usage outcomes, symptoms and quality of life. As with the evidence for the auto-CPAP, adverse events are measured disparately.

AUTHORS' CONCLUSIONS

In adults with moderate to severe sleep apnoea starting positive airway pressure therapy, auto-CPAP probably increases machine usage by about 13 minutes per night. The effects on daytime sleepiness scores with auto-CPAP are not clinically meaningful. AHI values are slightly lower with fixed CPAP. Use of validated quality of life instruments in the studies to date has been limited, although where they have been used the effect sizes have not exceeded proposed clinically important differences. The adoption of a standardised approach to measuring tolerability would help decision-makers to balance benefits with harms from the different treatment options available. The evidence available for other pressure modification strategies does not provide a reliable basis on which to draw firm conclusions. Future studies should look at the effects of pressure modification devices and humidification in people who have already used CPAP but are unable to persist with treatment.

When Office Blood Pressure Is Not Enough: The Case of Masked Hypertension

An increasing attention has been devoted in the last two decades to masked hypertension (MH), a condition characterized by the fact that classification of a normal blood pressure (BP) status by office measurements is not confirmed by home and/or ambulatory BP monitoring (ABPM). MH definition (i.e., normal office BP, but high out-of-office BP) should be restricted to untreated subjects (true MH) whereas masked uncontrolled hypertension (MUCH) reserved to treated patients previously classified as hypertensives, presenting normal office BP and high ABPM or home values. Both MH and MUCH are associated with metabolic alterations, comorbidities, and hypertension-mediated organ damage (HMOD). Furthermore, the risk of cardiovascular events related to these conditions has been shown to be close or greater than that of sustained hypertension. This review discusses available evidence about MH and MUCH by focusing on its prevalence, clinical correlates, association with HMOD, prognostic significance, and their therapeutic implications.

Masked hypertension and kidney function decline: the Jackson Heart Study

BACKGROUND

Hypertension diagnosed by blood pressure (BP) measured in the clinic is associated with rapid kidney function decline (RKFD) and incident chronic kidney disease (CKD). The extent to which hypertension defined using out-of-clinic BP measurements is associated with these outcomes is unclear.

METHODS

We evaluated the association of any masked hypertension (daytime SBP/DBP ≥ 135/85 mmHg, night-time SBP/DBP ≥ 120/70 mmHg or 24-h SBP/DBP ≥ 130/80 mmHg) with RKFD and incident CKD among 676 African-Americans in the Jackson Heart Study with clinic-measured SBP/DBP less than 140/90 mmHg who completed ambulatory BP monitoring in 2000-2004. RKFD was defined as a decline in estimated glomerular filtration rate (eGFR) at least 30% and incident CKD was defined as development of eGFR less than 60 ml/min per 1.73 m with an at least 25% decline in eGFR between 2000-2004 and 2009-2013.

RESULTS

The mean age of participants was 57.6 years, 28.8% were men and 52.7% had any masked hypertension. After a median follow-up of 8 years, 13.8 and 8.6% of participants had RKFD and incident CKD, respectively. In unadjusted analyses, masked hypertension was associated with an increased odds for incident CKD [odds ratio (OR) 2.20, 95% confidence interval (CI) 1.22, 3.97]. This association remained statistically significant after adjustment for demographic characteristics, baseline eGFR and albumin-to-creatinine ratio (OR 1.95, 95% CI 1.04, 3.67) but was eliminated after propensity score adjustment (OR 1.62, 95% CI 0.87, 3.00). There was no association between masked hypertension and RKFD.

CONCLUSION

Masked hypertension may be associated with the development of CKD in African-Americans.

Role and prognostic value of individual ambulatory blood pressure components in chronic kidney disease

Hypertension is a key risk factor for chronic kidney disease (CKD), but can also be a detrimental consequence of established CKD. Unsurprisingly, the majority of subjects with abnormal creatinine in the general population are also hypertensive, with a huge toll on national health care systems worldwide due to a staggering increase in the risk of cardiovascular complications and end-stage renal disease requiring renal replacement therapy. In this setting, a comprehensive and careful assessment of the whole 24-h blood pressure (BP) profile could be of paramount importance in ensuring a timely diagnosis of hypertension and an optimal therapeutic control. Hence, ambulatory BP monitoring (ABPM) has the potential to become the preferred method for optimal clinical management of CKD patients. ABPM might better define the relationship between BP, target organ damage (TOD), and clinical outcomes. Current evidence suggests that specific day-night BP components, along with average BP values, may have clinical relevance in such patients, despite the suboptimal statistical power of available studies and inconsistencies on the prognostic value of individual BP components. The main aim of our review is to scrutinize the evidence for the usage of ABPM in CKD patients, including the relationship between ambulatory BP recordings and cardiovascular events, and the distinctive features of ABPM in these subjects.

Clinical Correlates of Ambulatory Blood Pressure Phenotypes at a Tertiary Care Hospital in Turkey

BACKGROUND/AIMS

Hypertension and its complications are major public health issues worldwide due to their association with high cardiovascular morbidity and mortality. Despite significant progress in health, the prevalence of hypertension is increasing. Ambulatory blood pressure monitoring (ABPM) is becoming increasingly important for the management of hypertension. In this study, we aimed to investigate the clinical and laboratory correlates of ambulatory blood pressure (ABP) phenotypes at a tertiary care hospital in Turkey.

METHODS

The characteristics of 1053 patients were retrospectively obtained from the hospital database. Hypertension was defined as patients with office blood pressure (BP) ≥140/90 mmHg and/or previously diagnosed hypertension and/or the use of antihypertensive medication. According to the office BP and ABPM results patients were identified namely: (1) sustained normotensive (SNT) patients (both office BP and ABPM were normal), (2) sustained hypertensive (SHT) patients (both office BP and ABPM were high), (3) masked hypertensive (MHT) patients (office BP were normal, but ABPM were high), (4) white coat hypertensive (WCHT) patients (office BP were above limits, but ABPM were normal).

RESULTS

A total of 1053 patients were included to the study (female/male: 608/445 and mean age 55 ± 15 years). The mean age of patients with hypertension was significantly higher than without hypertension (p< 0.0001). Hypertension was more frequent in females (p=0.009). The rates of history of diabetes mellitus (DM), hyperlipidemia (HL), and chronic kidney disease (CKD) were higher in patients with hypertension (p< 0.0001). Among patients with hypertension (n=853, 81%), ABPM results showed that 388 (45%) of patients had SHT, 92 (11%) had MHT, and 144 (17%) had WCHT, whereas 229 (27%) had SNT. Patients with MHT were significantly older than patients with SNT (p=0.025). The prevalence of SHT was higher in men than in women, whereas the prevalence of WCHT was higher in women than in men (p< 0.0001). There was no significant difference between 4 groups with regard to body mass index (p=0.142), a history of DM (p=0.189) and smoking status (self-reported) (p=0.306). Patients with SHT had the highest prevalence of history of hypertension, HL and CKD (p< 0.0001). Among patients without hypertension, 26 (13%) of patients had MHT and none of those patients was on antihypertensive treatment.

CONCLUSION

Potential usages of ABPM in Turkey may include screening of high risk individuals who have traditional cardiovascular risk factors. It also provides clinicians valuable information on abnormal ABP phenotypes. Future studies are needed to clarify the risk factors of different ABP phenotypes and to evaluate the role of ABPM on detection and control of hypertension.

Increased masked hypertension prevalence in patients with obesity

OBJECTIVES

Masked hypertension is associated with an increased risk for cardiovascular conditions. The aim of the study was to evaluate the relationship obesity parameters, including body weight, waist circumference, and body mass index.

METHODS

The study group consisted of 251 consecutive outpatient subjects without overt hypertension. Subjects were classified according to BMI. After a complete medical history and laboratory examination, patients' height, weight, waist circumference heart rate, and office blood pressure were recorded. All subjects underwent ambulatory blood pressure monitoring. Masked hypertension is defined as normal office blood pressure measurement and high ambulatory blood pressure level.

RESULTS

Baseline characteristics in patients and controls were similar. Prevalence of Masked hypertension was significantly higher in patients with obesity than controls (30.9% vs 5.7%, p < 0.001). Body mass index (33.2 ± 4.3 vs 25.1 ± 2.7 p < 0.001), waist circumference (98.5 ± 11.7 vs 86.8 ± 8.8, p < 0.001), and weight (86.5 ± 11.8 vs. 69 ± 9.1, p < 0.001) in patients with obesity were significantly higher than in patients with normal weight. Office Systolic BP (121.8 ± 4.4 vs 120.5 ± 4.78, p = 0.035), ambulatory daytime systolic BP (128.8 ± 8.9 vs 124.5 ± 7.4, p < 0.001), ambulatory daytime diastolic BP (73.9 ± 9.5 vs 71.5 ± 7.0, p = 0.019), ambulatory night-time systolic BP in patients with obesity was significantly higher than in patients with normal weight.

CONCLUSION

This study demonstrated that masked hypertension prevalence is higher in patients with obesity than control patients. It can be suggested that predefining obesity might be helpful in early detection of masked hypertension.

Prevalence of Hypertensive Phenotypes After Preeclampsia: A Prospective Cohort Study

Preeclampsia is associated with increased cardiovascular and renal risk. The aim of this prospective cohort study was to characterize the early postpartum blood pressure (BP) profile after preeclampsia. We enrolled 115 women with preeclampsia and 41 women with a normal pregnancy in a prospective cohort study. At 6 to 12 week postpartum, we assessed the prevalence of different hypertensive phenotypes using 24-hour ambulatory BP monitoring (ABPM), as well as the risk of salt sensitivity and the variability of BP derived from ABPM parameters. Among patients with preeclampsia, 57.4% were still hypertensive at the office. Daytime ABP was significantly higher in the preeclampsia group (118.9±15.0/83.2±10.4 mm Hg) than in controls (104.8±7.9/71.6±5.3 mm Hg; P<0.01). Differences between groups were similar for nocturnal BP values. Fifty percent of preeclampsia women remained hypertensive on ABPM in the postpartum, of whom 24.3% were still under antihypertensive treatment; 17.9% displayed a white-coat hypertension and 11.6% had masked hypertension. In controls, 2.8% had white-coat hypertension; none had masked hypertension or needed hypertensive treatment. The prevalence of nondippers was similar 59.8% in the preeclampsia group versus 51.4% in controls. High-risk class of salt sensitivity of BP was increased in preeclampsia women (48.6%) compared with controls (17.1%); P<0.01. In conclusion, ABPM 6 to 12 weeks after delivery reveals a high rate of sustained ambulatory, nocturnal, and masked hypertension after preeclampsia. This finding may help identify women who should be included in a postpartum cardiovascular risk management program.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01095939.

Predicted Atherosclerotic Cardiovascular Disease Risk and Masked Hypertension Among Blacks in the Jackson Heart Study

BACKGROUND

Among individuals without hypertension based on clinic blood pressure (BP), it is unclear who should be screened for masked hypertension, defined as having hypertension based on out-of-clinic BP. We hypothesized that individuals with a higher 10-year predicted atherosclerotic cardiovascular disease (ASCVD) risk, calculated using the pooled cohort risk equations, have a higher prevalence of masked hypertension.

METHODS AND RESULTS

We analyzed data from the Jackson Heart Study-a population-based cohort of blacks-to determine the association of predicted ASCVD risk with masked hypertension. The sample included 644 participants, 40 to 79 years of age, with clinic systolic/diastolic BP <140/90 mm Hg, who completed ambulatory BP monitoring, were free of cardiovascular disease, and had data on factors needed to calculate ASCVD risk. Ten-year predicted ASCVD risk was calculated using the pooled cohort risk equations. Any masked hypertension was defined as masked daytime hypertension (mean daytime systolic/diastolic BP ≥135/85 mm Hg), masked nighttime hypertension (mean nighttime systolic/diastolic BP ≥120/70 mm Hg), or masked 24-hour hypertension (mean 24-hour systolic/diastolic BP ≥130/80 mm Hg). The prevalence of any masked hypertension was 54.0%. Compared with participants in the lowest (<5%) predicted ASCVD risk category, multivariable-adjusted prevalence ratios (95% confidence interval) for any masked hypertension were 1.36 (1.03-1.79), 1.62 (1.22-2.16), and 1.91 (1.47-2.48) for those with ASCVD risk of 5% to <7.5%, 7.5% to <10%, and ≥10%, respectively. The C statistic for discriminating between participants with versus without any masked hypertension was 0.681 (95% confidence interval, 0.640-0.723) for ASCVD risk and 0.703 (95% confidence interval, 0.663-0.744) for clinic systolic BP and diastolic BP.

CONCLUSIONS

Higher ASCVD risk was associated with an increased prevalence of masked hypertension. Although the discrimination of ASCVD risk for masked hypertension was not superior to clinic BP, risk prediction equations may be useful for identifying the subgroup of individuals with both masked hypertension and high predicted ASCVD risk.

Masked hypertension in obesity: potential predictors and arterial damage

Background

Masked hypertension (MHT), defined as normal office blood pressure (BP) but high ambulatory BP, has been associated with increased cardiovascular risk. Although MHT has been associated with obesity, there is limited knowledge on the prevalence and covariates of MHT in obese cohorts.

Methods

Office and ambulatory BP recordings and other cardiovascular risk factors were assessed in 323 obese participants included in the fat-associated cardiovascular dysfunction study (mean age 48.9±9.0 years, 55% women, mean BMI 32.3±4.4 kg/m²). Office BP 130–139/85–89 mmHg was considered high-normal. Subclinical arterial damage was identified as carotid–femoral pulse wave velocity more than 10 m/s by applanation tonometry or carotid plaque by ultrasound (maximal intima–media thickness ≥1.5 mm).

Results

MHT was present in 17.1% of the population. Patients with MHT had a higher prevalence of metabolic syndrome, high-normal office BP, and were more often male compared with the normotensive (NT) individuals (all P<0.05), but were younger and had lower prevalence of diabetes and subclinical arterial damage than the sustained hypertensive group (all P<0.05). In multinomial logistic regression analysis, MHT was associated with the presence of metabolic syndrome and high-normal office BP compared with NT individuals, and lower pulse wave velocity and fewer carotid plaques than sustained hypertension (all P<0.05).

Conclusion

In obese patients, MHT was associated with the presence of metabolic syndrome and high-normal office BP compared with NT individuals, but less subclinical arterial damage than sustained hypertensive patients.

A possible cause of epistaxis: increased masked hypertension prevalence in patients with epistaxis

Introduction

Epistaxis and hypertension are frequent conditions in the adult population. Masked hypertension is defined as a clinical condition in which a patient's office blood pressure level is <140/90 mmHg, but the ambulatory or home blood pressure readings are in the hypertensive range. Many studies have proved that hypertension is one of the most important causes of epistaxis. The prevalence of this condition in patients with epistaxis is not well defined.

Objective

This study aimed to evaluate the prevalence of masked hypertension using the results of office blood pressure measurement compared with the results of ambulatory blood pressure monitoring.

Methods

Sixty patients with epistaxis and 60 control subjects were enrolled in the study. All patients with epistaxis and controls without history of hypertension underwent physical examination, including office blood pressure measurement, ambulatory or home blood pressure, and measurement of anthropometric parameters.

Results

Mean age was similar between the epistaxis group and the controls – 21–68 years (mean 42.9) for the epistaxis group and 18–71 years (mean 42.2) for the control group. A total of 20 patients (33.3%) in the epistaxis group and 7 patients (11.7%) in the control group (p = 0.004) had masked hypertension. Night-time systolic blood pressure was significantly higher in patients with epistaxis than in the control group (p < 0.005). However, no significant difference was found in daytime systolic blood pressure between the control group and the patients with epistaxis (p = 0.517).

Conclusion

This study demonstrates increased masked hypertension prevalence in patients with epistaxis. We suggest that all patients with epistaxis should undergo ambulatory or home blood pressure to detect masked hypertension, which could be a possible cause of epistaxis.

A new diagnostic tool for masked hypertension: impaired sleep quality

INTRODUCTION

The aim of this study was to evaluate the relationship between masked hypertension and impaired sleep quality. Additionally, we evaluated the diagnostic role and prevalence of poor sleep quality among patients with newly diagnosed masked hypertension.

MATERIAL AND METHODS

A total of 112 individuals, 72 patients with newly diagnosed masked hypertension and 40 normotensive healthy volunteers, were included in this study. All patients underwent evaluation comprising 12-lead electrocardiography, transthoracic echocardiography, 24-hour Holter ECG, and basic laboratory tests. Additionally, all participants completed questionnaires, including the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

The total PSQI score was significantly higher in the masked hypertension group than in the normotensive healthy volunteers (4.13 ±2.43 vs. 2.33 ±1.67, p < 0.001). A PSQI score > 5 was found in 45.8% (n = 33) of patients in the masked hypertension group and 15% (n = 6) of patients in the normotensive group (p < 0.001). The non-dipper pattern was found in 17.5% of the healthy volunteer group and 59.94% (n = 41) of the masked hypertension group (p < 0.001). When we compared the dipping pattern of the masked hypertension groups, there was a significant difference in PSQI score between the dipper and non-dipper groups (4.87 ±3.21 vs. 3.58 ±2.33, p < 0.001). Multiple logistic regression analyses showed that masked hypertension, LV mass, and LV mass index score were independent predictors of poor PSQI.

CONCLUSIONS

This study demonstrates impaired sleep quality in subjects with masked hypertension, particularly those with a non-dipper pattern. Additionally, this study indicates that impaired sleep quality may help diagnose masked hypertension, particularly in the non-dipper group.

Prevalence of Masked Hypertension: a Population-Based Survey in a Large City by Using 24-Hour Ambulatory Blood Pressure Monitoring

Background and Objectives

We estimated the prevalence of hypertension and hypertension subtypes in a large semi-urban city in Korea, using 24-hour ambulatory blood pressure monitoring (ABPM) in a randomly selected sample population.

Subjects and Methods

A random sample (aged 20-65 years) from a city with an adult population of approximately 600000 was selected by using a list-assisted random digit dialing method. The 24-hour ABPM and conventional blood pressure measurement (CBPM) of these individuals were obtained.

Results

Among the 496 participants, valid 24-hour ABPM and CBPM were obtained from 462 (93%) individuals. The estimated prevalence of hypertension in Goyang was 17.54% by CBPM and 32.70% by 24-hour ABPM (p<0.01). In the age stratified analysis, both CBPM and 24-hour ABPM showed increased prevalence of hypertension with age. The estimated prevalence of masked hypertension was 16.22% and that of white-coat hypertension was 1.08%. Men had a higher prevalence of masked hypertension than women (20.79% vs. 11.86%, p=0.0295). The estimated prevalence of masked hypertension was 17.5%, 20.58%, 24.34%, and 13.29% in the age categories of 30s, 40s, 50s, and 60s, respectively. The estimated prevalence of masked uncontrolled hypertension was 26.79% in patients with hypertension who were taking antihypertensive medications.

Conclusion

The estimated prevalence of hypertension by 24-hour ABPM was higher than that by CBPM, revealing high prevalence of masked hypertension. The high prevalence of masked hypertension supports the adoption of ABPM in the national population survey and clinical practice to improve public health and reduce health care costs.

Masked Hypertension and Cardiovascular Disease Events in a Prospective Cohort of Blacks: The Jackson Heart Study

Masked hypertension, defined as nonelevated clinic blood pressure (BP) with elevated out-of-clinic BP, has been associated with increased cardiovascular disease (CVD) risk in Europeans and Asians. Few data are available on masked hypertension and CVD and mortality risk among blacks. We analyzed data from the Jackson Heart Study, a prospective cohort study of blacks. Analyses included participants with clinic-measured systolic/diastolic BP <140/90 mm Hg who completed ambulatory BP monitoring after the baseline examination in 2000 to 2004 (n=738). Masked daytime (10:00 am-8:00 pm) hypertension was defined as mean ambulatory systolic/diastolic BP ≥135/85 mm Hg. Masked nighttime (midnight to 6:00 am) hypertension was defined as mean ambulatory systolic/diastolic BP ≥120/70 mm Hg. Masked 24-hour hypertension was defined as mean systolic/diastolic BP ≥130/80 mm Hg. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction, or fatal coronary heart disease) and deaths identified through December 2010 were adjudicated. Any masked hypertension (masked daytime, nighttime, or 24-hour hypertension) was present in 52.2% of participants; 28.2%, 48.2% and 31.7% had masked daytime, nighttime, and 24-hour hypertension, respectively. There were 51 CVD events and 44 deaths during a median follow-up of 8.2 and 8.5 years, respectively. CVD rates per 1000 person-years (95% confidence interval) in participants with and without any masked hypertension were 13.5 (9.9-18.4) and 3.9 (2.2-7.1), respectively. The multivariable adjusted hazard ratio (95% confidence interval) for CVD was 2.49 (1.26-4.93) for any masked hypertension and 2.86 (1.59-5.13), 2.35 (1.23-4.50), and 2.52 (1.39-4.58) for masked daytime, nighttime, and 24-hour hypertension, respectively. Masked hypertension was not associated with all-cause mortality. Masked hypertension is common and associated with increased risk for CVD events in blacks.

Masked Hypertension: How to Identify and When to Treat?

Approximately one out of 7-8 individuals with normal blood pressure (BP) in the clinic or doctor's office and one third of patients with chronic kidney disease with normal clinic BP have elevated ambulatory BP (masked hypertension). Patients with masked hypertension have an increased risk for target organ damage and a two-fold increased risk for cardiovascular events compared to patients with normal clinic and ambulatory BP. Despite this elevated risk for adverse outcomes, patients with masked hypertension have been excluded from hypertension trials because of their normal clinic BP. It is still unknown whether the reduction in target organ damage and adverse cardiovascular outcomes associated with treatment of hypertension extends to patients with masked hypertension. Ongoing and planned interventional studies will provide an answer to this crucial question in a few years. At present, it seems reasonable to follow the suggestion of current European guidelines, that lifestyle measures and drug treatment should be considered in the presence of masked hypertension.

Prevalence of Masked Hypertension and Its Association With Subclinical Cardiovascular Disease in African Americans: Results From the Jackson Heart Study

Background

Studies consisting mostly of whites have shown that the prevalence of masked hypertension differs by prehypertension status. Using data from the Jackson Heart Study, an exclusively African American population‐based cohort, we evaluated the association of masked hypertension and prehypertension with left ventricular mass index and common carotid intima media thickness.

Methods and Results

At the baseline visit, clinic blood pressure (CBP) measurement and 24‐hour ambulatory blood pressure monitoring were performed. Masked hypertension was defined as mean systolic/diastolic CBP <140/90 mm Hg and mean daytime systolic/diastolic ambulatory blood pressure ≥135/85 mm Hg. Clinic hypertension was defined as mean systolic/diastolic CBP ≥140/90 mm Hg. Normal CBP was defined as mean systolic/diastolic CBP <120/80 mm Hg and prehypertension as mean systolic/diastolic CBP 120 to 139/80 to 89 mm Hg. The analytic sample included 909 participants. Among participants with systolic/diastolic CBP <140/90 mm Hg, the prevalence of masked hypertension and prehypertension was 27.5% and 62.4%, respectively. The prevalence of masked hypertension among those with normal CBP and prehypertension was 12.9% and 36.3%, respectively. In a fully adjusted model, which included prehypertension status and antihypertensive medication use as covariates, left ventricular mass index was 7.94 g/m² lower among those without masked hypertension compared to participants with masked hypertension (P<0.001). Left ventricular mass index was also 4.77 g/m² lower among those with clinic hypertension, but this difference was not statistically significant (P=0.068). There were no significant differences in left ventricular mass index between participants with and without masked hypertension, or clinic hypertension.

Conclusions

Masked hypertension was common among African Americans with prehypertension and also normal CBP, and was associated with subclinical cardiovascular disease.

Evaluation of prehypertension and masked hypertension rate among clinically normotensive patients

BACKGROUND

The present cross-sectional study was aimed to identify pre-hypertension and masked hypertension rate in clinically normotensive adults in relation to socio-demographic, clinical and laboratory parameters.

METHODS

A total of 161 clinically normotensive adults with office blood pressure (OBP) <140/90 mmHg without medication were included in this single-center cross-sectional study. OBP, home BP (HBP) recordings and ambulatory BP monitoring (ABPM) were used to identify rates of true normotensives, true pre-hypertensives and masked hypertensives. Data on sociodemographic and clinical characteristics were collected in each subject and evaluated with respect to true normotensive vs. pre-hypertensive patients with masked hypertension or true pre-hypertensive. Target organ damage (TOD) was evaluated in masked hypertensives based on laboratory investigation.

RESULTS

Masked hypertension was identified in 8.7% of clinically normotensives. Alcohol consumption was significantly more common in masked hypertension than in true pre-hypertension (28.6 vs. 0.0%, p = 0.020) with risk ratio of 2.7 (95% CI 1.7-4.4). Patients with true pre-hypertension and masked hypertension had significantly higher values for body mass index, waist circumference, systolic and diastolic OBP and HBP (p < 0.05 for each) compared to true normotensive subjects. ABPM revealed significantly higher values for day-time and night-time systolic and diastolic BP (p = 0.002 for night-time diastolic BP, p < 0.001 for others) in masked hypertension than true pre-hypertension.

CONCLUSIONS

Given that the associations of pre-hypertension with TOD might be attributable to the high prevalence of insidious presentation of masked hypertension among pre-hypertensive individuals, ABPM seems helpful in early identification and management of masked hypertension in the pre-hypertensive population.

What is the evidence base for diagnosing hypertension and for subsequent blood pressure treatment targets in the prevention of cardiovascular disease?

Diagnosing and treating hypertension plays an important role in minimising the risk of cardiovascular disease and stroke. Early and accurate diagnosis of hypertension, as well as regular monitoring, is essential to meet treatment targets. In this article, current recommendations for the screening and diagnosis of hypertension are reviewed. The evidence for treatment targets specified in contemporary guidelines is evaluated and recommendations from the USA, Canada, Europe and the UK are compared. Finally, consideration is given as to how diagnosis and management of hypertension might develop in the future.

Prevalence, Determinants, and Clinical Significance of Masked Hypertension in a Population-Based Sample of African Americans: The Jackson Heart Study

BACKGROUND

The disproportionate rates of cardiovascular disease in African Americans may, in part, be due to suboptimal assessment of blood pressure (BP) with clinic BP measurements alone. To date, however, the prevalence of masked hypertension in African Americans has not been fully delineated. The purpose of this study was to evaluate masked hypertension prevalence in a large population-based sample of African Americans and examine its determinants and association with indices of target organ damage (TOD).

METHODS

Clinic and 24-hour ambulatory BP monitoring were conducted in 972 African Americans enrolled in the Jackson Heart Study. Common carotid artery intima-media thickness, left ventricular mass index, and the urinary albumin:creatinine excretion ratio were evaluated as indices of TOD.

RESULTS

Masked hypertension prevalence was 25.9% in the overall sample and 34.4% in participants with normal clinic BP. All indices of TOD were significantly higher in masked hypertensives compared to sustained normotensives and were similar between masked hypertensives and sustained hypertensives. Male gender, smoking, diabetes, and antihypertensive medication use were independent determinants of masked hypertension in multivariate analyses.

CONCLUSIONS

In this population-based cohort of African Americans, approximately one-third of participants with presumably normal clinic BP had masked hypertension when BP was assessed in their daily environment. Masked hypertension was accompanied by a greater degree of TOD in this cohort.

Clinical value of ambulatory blood pressure: evidence and limits

This article reviews the clinical value of ambulatory blood pressure (BP) vis-à-vis the traditional BP measurements taken in the physician's office or in the hospital. Mention is initially made that longitudinal studies conducted in the general population or in hypertensive cohorts have shown that ambulatory BP provides a more accurate prediction of outcome than office BP. Namely, that (1) the risk of cardiovascular events increases in a less steep fashion with office than with 24-hour mean BP, (2) the 24-hour BP-dependent prediction is maintained after adjustment for office BP values, and (3) among individuals with normal office BP, those with increased ambulatory BP (masked hypertension) have an increased prevalence of organ damage, a more frequent unfavorable metabolic profile and a higher risk of new onset sustained hypertension, diabetes mellitus, and cardiovascular events than those with normal ambulatory BP. It is further mentioned, however, that more recently similar observations have been made for individuals with high office but normal ambulatory BP (white coat hypertension) suggesting a complementary role of out-of-office and office BP values in the determination of patients' prognosis. The evidence in favor of an independent prognostic value also of some within 24-hour BP phenomena (night BP reduction or absolute values, short-term BP variations, and morning BP surge) is then critically appraised for its elements of strength and weakness. Finally, whether the clinical advantages of ambulatory BP make this approach necessary for all patients with hypertension is discussed. The conclusion is that this is at present still premature because crucial evidence pro or against routine use of this approach in untreated and treated hypertensives is not yet available. It will be crucial for future studies to determine whether, compared with a treatment guided by office BP, a treatment tailored on ambulatory BP allows to improve prevention or regression of organ damage as well as protection from major cardiovascular complications to a degree that justifies the complexity and cost of the procedure.

Untreated Masked Hypertension and Subclinical Cardiac Damage: A Systematic Review and Meta-analysis

AIM

Data on the association of masked hypertension (MH) (i.e., normal office and elevated out-of-office blood pressure (BP)) with cardiac damage are scanty. We performed a meta-analysis in order to provide a comprehensive information on subclinical cardiac alterations in subjects with MH.

DESIGN

Studies were identified by the following search terms: "masked hypertension," "white coat normotension," "isolated ambulatory hypertension," "left ventricular mass," "left ventricular hypertrophy," "cardiac damage," and "echocardiography." Full articles published in English language providing data on left ventricular (LV) mass and/or prevalence of LV hypertrophy in MH, as assessed by ambulatory BP monitoring, were considered.

RESULTS

Overall, 4,884 untreated subjects (2,467 normotensive, 776 MH, and 1,641 sustained hypertensive individuals) of both genders included in 12 studies were analyzed. LV mass index showed a progressive increase from normotensive (79.2 ± 0.35 g/m(2)) to MH (91.6 ± 4.0 g/m(2)) (standard difference in means (SDM): 0.50 ± 0.11, confidence interval (CI): 0.28-0.73, P < 0.01) and to hypertensive subjects (102.9 ± 3.3g/m(2)) (SDM: 0.22 ± 0.07, CI: 0.09-0.35, P < 0.01). After assessing data for publication bias, the difference between groups was still significant.

CONCLUSIONS

Our findings support an association between MH and increased risk of LV structural alterations compared to true normotensive individuals. Due to the worse cardiovascular prognosis associated with subclinical cardiac damage, subjects with MH should be carefully screened in order to detect hypertensive organ damage and provide appropriate therapeutic interventions.

Association of isolated systolic, isolated diastolic, and systolic-diastolic masked hypertension with carotid artery intima-media thickness

Masked hypertension (MH) is associated with advanced target organ damage. However, patients with MH constitute a group of individuals with heterogeneous characteristics concerning their ambulatory blood pressure (BP) status. The aim of this study was to evaluate the association of isolated systolic MH, isolated diastolic MH, and systolic/diastolic MH with carotid artery intima-media thickness (CIMT). A total of 101 patients with MH underwent carotid artery ultrasonographic measurements. The patients were divided into three groups according to office and daytime BP values: isolated systolic MH, isolated diastolic MH, and systolic/diastolic MH. Patients with isolated systolic (n=36) (0.771 mm) and systolic/diastolic MH (n=37) (0.775 mm) had significantly (P<.05) higher CIMT values than those with isolated diastolic MH (n=28) (0.664 mm), even after adjustment for baseline characteristics and risk factors. Patients with isolated systolic and systolic/diastolic MH presented significantly higher CIMT values compared with patients with isolated diastolic MH.

Ambulatory blood pressure monitoring in the elderly: features and perspectives

Aging leads to a multitude of changes in the cardiovascular system that include a rise in blood pressure. Age-related changes in blood pressure are mainly attributable to an increase in systolic blood pressure, generally associated with a slight decrease diastolic blood pressure. This leads to a widening in pulse pressure. Ambulatory blood pressure monitoring is a useful tool to understand these processes and to refine cardiovascular risk assessment. In the light of emerging data in this area, we reviewed the main features of ambulatory blood pressure in elderly and discussed the evidence showing that ambulatory blood pressure is superior to clinic blood pressure to reflect the true pattern of blood pressure over time. Furthermore, we discussed the role of weight control obtained by fitness programs to prevent an excessive rise in blood pressure with age. A thorough understanding of these concepts is of paramount importance and has therapeutic implications in the growing population of elderly subjects with increased blood pressure.

Canadian Society of Nephrology commentary on the 2012 KDIGO clinical practice guideline for the management of blood pressure in CKD

The KDIGO (Kidney Disease: Improving Global Outcomes) 2012 clinical practice guideline for the management of blood pressure (BP) in chronic kidney disease (CKD) provides the structural and evidence base for the Canadian Society of Nephrology (CSN) commentary on this guideline's relevancy and application to the Canadian health care system. While in general agreement, we provide commentary on 13 of the 21 KDIGO guideline statements. Specifically, we agreed that nonpharmacological interventions should play a significant role in the management of hypertension in patients with CKD. We also agreed that the approach to the management of hypertension in elderly patients with CKD should be individualized and take into account comorbid conditions to avoid adverse outcomes from excessive BP lowering. In contrast to KDIGO, the CSN Work Group believes there is insufficient evidence to target a lower BP for nondiabetic CKD patients based on the presence and severity of albuminuria. The CSN Work Group concurs with the Canadian Hypertension Education Program (CHEP) recommendation of a target BP for all non-dialysis-dependent CKD patients without diabetes of ≤140 mm Hg systolic and ≤90 mm Hg diastolic. Similarly, it is our position that in diabetic patients with CKD and normal urinary albumin excretion, raising the threshold for treatment from <130 mm Hg systolic BP to <140 mm Hg systolic BP could increase stroke risk and the risk of worsening kidney disease. The CSN Work Group concurs with the CHEP and the Canadian Diabetic Association recommendation for diabetic patients with CKD with or without albuminuria to continue to be treated to a BP target similar to that of the overall diabetes population, aiming for BP levels < 130/80 mm Hg. Consistent with this, the CSN Work Group endorses a BP target of <130/80 mm Hg for diabetic patients with a kidney transplant. Finally, in the absence of evidence for a lower BP target, the CSN Work Group concurs with the CHEP recommendation to target BP<140/90 mm Hg for nondiabetic patients with a kidney transplant.

Clinical utility of ambulatory blood pressure monitoring in the management of hypertension

Accurate blood pressure (BP) measurement is essential for the diagnosis, monitoring and management of hypertension. However, conventional office-based BP readings have several limitations that include a low reproducibility, the white-coat effect and the existence of masked hypertension. These limitations can be addressed through the use of ambulatory BP monitoring. Because ambulatory monitoring provides measurements at specific time intervals throughout a 24-hour period, this technique represents a better picture of the normal fluctuations in BP levels associated with daily activities and sleep. In addition, end-organ damage associated with hypertension is more closely related to ambulatory BP than office BP measurements and ambulatory BP profile give better prediction of clinical outcome than conventional BP measurements.

Epidemiology of masked and white-coat hypertension: the family-based SKIPOGH study

Objective

We investigated factors associated with masked and white-coat hypertension in a Swiss population-based sample.

Methods

The Swiss Kidney Project on Genes in Hypertension is a family-based cross-sectional study. Office and 24-hour ambulatory blood pressure were measured using validated devices. Masked hypertension was defined as office blood pressure<140/90 mmHg and daytime ambulatory blood pressure≥135/85 mmHg. White-coat hypertension was defined as office blood pressure≥140/90 mmHg and daytime ambulatory blood pressure<135/85 mmHg. Mixed-effect logistic regression was used to examine the relationship of masked and white-coat hypertension with associated factors, while taking familial correlations into account. High-normal office blood pressure was defined as systolic/diastolic blood pressure within the 130–139/85–89 mmHg range.

Results

Among the 652 participants included in this analysis, 51% were female. Mean age (±SD) was 48 (±18) years. The proportion of participants with masked and white coat hypertension was respectively 15.8% and 2.6%. Masked hypertension was associated with age (odds ratio (OR) = 1.02, p = 0.012), high-normal office blood pressure (OR = 6.68, p<0.001), and obesity (OR = 3.63, p = 0.001). White-coat hypertension was significantly associated with age (OR = 1.07, p<0.001) but not with education, family history of hypertension, or physical activity.

Conclusions

Our findings suggest that physicians should consider ambulatory blood pressure monitoring for older individuals with high-normal office blood pressure and/or who are obese.

Unmasking masked hypertension: prevalence, clinical implications, diagnosis, correlates and future directions

'Masked hypertension' is defined as having non-elevated clinic blood pressure (BP) with elevated out-of-clinic average BP, typically determined by ambulatory BP monitoring. Approximately 15-30% of adults with non-elevated clinic BP have masked hypertension. Masked hypertension is associated with increased risks of cardiovascular morbidity and mortality compared with sustained normotension (non-elevated clinic and ambulatory BP), which is similar to or approaching the risk associated with sustained hypertension (elevated clinic and ambulatory BP). The confluence of increased cardiovascular risk and a failure to be diagnosed by the conventional approach of clinic BP measurement makes masked hypertension a significant public health concern. However, many important questions remain. First, the definition of masked hypertension varies across studies. Further, the best approach in the clinical setting to exclude masked hypertension also remains unknown. It is unclear whether home BP monitoring is an adequate substitute for ambulatory BP monitoring in identifying masked hypertension. Few studies have examined the mechanistic pathways that may explain masked hypertension. Finally, scarce data are available on the best approach to treating individuals with masked hypertension. Herein, we review the current literature on masked hypertension including definition, prevalence, clinical implications, special patient populations, correlates, issues related to diagnosis, treatment and areas for future research.