Masked Uncontrolled Hypertension in Patients Treated for HTN
Masked Uncontrolled Hypertension in Patients Treated for HTN
Aim There are limited data on the quality of treated blood pressure (BP) control during normal daily life, and in particular, the prevalence of 'masked uncontrolled hypertension' (MUCH) in people with treated and seemingly well-controlled BP is unknown. This is important because masked hypertension in 'treatment naïve' patients is associated with a high risk of cardiovascular events. We therefore conducted the first study to define the prevalence and characteristics of MUCH among a large sample of hypertensive patients in routine clinical practice in whom BP was treated and controlled to recommended clinic BP goals.
Methods and results We analysed data from the Spanish Society of Hypertension ambulatory blood pressure monitoring (ABPM) Registry and identified patients with treated and controlled BP according to current international guidelines (clinic BP <140/90 mmHg). Masked uncontrolled hypertension was diagnosed in these patients if despite controlled clinic BP, the mean 24-h ABPM average remained elevated (24-h systolic BP ≥130 mmHg and/or 24-h diastolic BP ≥80 mmHg). From 62 788 patients with treated BP in the Spanish registry, we identified 14 840 with treated and controlled clinic BP, of whom 4608 patients (31.1%) had MUCH according to 24-h ABPM criteria (mean age 59.4 years, 59.7% men). The prevalence of MUCH was significantly higher in males, patients with borderline clinic BP (130–9/80–9 mmHg), and patients at high cardiovascular risk (smokers, diabetes, obesity). Masked uncontrolled hypertension was most often because of poor control of nocturnal BP, with the proportion of patients in whom MUCH was solely attributable to an elevated nocturnal BP almost double that solely attributable to daytime BP elevation (24.3 vs. 12.9%, P < 0.001).
Conclusion The prevalence of masked suboptimal BP control in patients with treated and well-controlled clinic BP is high. Clinic BP monitoring alone is thus inadequate to optimize BP control because many patients have an elevated nocturnal BP. These findings suggest that ABPM should become more routine to confirm BP control, especially in higher risk groups and/or those with borderline control of clinic BP.
Masked hypertension (MH) is a term used to define people who have a normal seated clinic blood pressure (BP) but an elevated out-of-office BP, as determined by ambulatory BP monitoring (ABPM) or home BP monitoring (HBPM). Masked hypertension is the opposite of the more commonly recognized 'white coat hypertension'. Patients with MH are now known to be at particularly high risk of developing cardiovascular disease (CVD) because they often remain undetected and untreated.
Most studies on the prevalence of MH have primarily focused on 'treatment naïve' patients, prior to the diagnosis of hypertension, and many of them based the measurements on HBPM or daytime ABPM, or were of small size. This daytime definition of MH would not include people whose sole abnormality is an elevation in nocturnal BP, which some studies suggest is the strongest predictor of CVD risk compared with daytime or 24-h mean pressures. Furthermore, few studies have established the prevalence of the equivalent of MH, i.e. 'masked uncontrolled hypertension', which we have termed MUCH, in patients with treated hypertension. We use MUCH to describe treated patients in whom BP levels are sub-optimally controlled according to ABPM, but who are considered controlled to clinic BP targets by current treatment guidelines recommendations (<140/90 mmHg), which universally recommend the use of seated clinic BP to monitor BP control. MUCH has gone unrecognized because few studies have used 24-h ABPM to determine the prevalence of suboptimal BP control in seemingly well-treated patients, and there are no such studies in large cohorts of treated patients attending usual clinical practice.
The normal range for ABPM values has been defined based on data from prospective studies. For the diagnosis of hypertension, the recent UK NICE guidelines defined a daytime mean ABPM of ≥135/85 mmHg as being equivalent to the usual seated clinic BP threshold of ≥140/90 mmHg. However, ABPM also yields values for nocturnal pressures, and previous studies have suggested an ABPM-based diagnostic threshold for nocturnal hypertension as ≥120/70 and ≥130/80 mmHg for the 24-h BP average.
Despite the recognized potential for clinic BP alone to both over- and underdiagnose hypertension, to date, no guidelines have recommended the routine use of ABPM to monitor the quality of BP control because there are very little data on the quality of BP control in routine clinical practice.
The Spanish ABPM registry was established to evaluate the utility of the wider use of ABPM, and we have used this large, well-characterized population of hypertensive patients specifically to determine the frequency of MUCH in patients with treated hypertension. To our knowledge, this is the first large-scale study to evaluate and report the prevalence and characteristics of MUCH in people with seemingly well-treated hypertension.
Abstract and Introduction
Abstract
Aim There are limited data on the quality of treated blood pressure (BP) control during normal daily life, and in particular, the prevalence of 'masked uncontrolled hypertension' (MUCH) in people with treated and seemingly well-controlled BP is unknown. This is important because masked hypertension in 'treatment naïve' patients is associated with a high risk of cardiovascular events. We therefore conducted the first study to define the prevalence and characteristics of MUCH among a large sample of hypertensive patients in routine clinical practice in whom BP was treated and controlled to recommended clinic BP goals.
Methods and results We analysed data from the Spanish Society of Hypertension ambulatory blood pressure monitoring (ABPM) Registry and identified patients with treated and controlled BP according to current international guidelines (clinic BP <140/90 mmHg). Masked uncontrolled hypertension was diagnosed in these patients if despite controlled clinic BP, the mean 24-h ABPM average remained elevated (24-h systolic BP ≥130 mmHg and/or 24-h diastolic BP ≥80 mmHg). From 62 788 patients with treated BP in the Spanish registry, we identified 14 840 with treated and controlled clinic BP, of whom 4608 patients (31.1%) had MUCH according to 24-h ABPM criteria (mean age 59.4 years, 59.7% men). The prevalence of MUCH was significantly higher in males, patients with borderline clinic BP (130–9/80–9 mmHg), and patients at high cardiovascular risk (smokers, diabetes, obesity). Masked uncontrolled hypertension was most often because of poor control of nocturnal BP, with the proportion of patients in whom MUCH was solely attributable to an elevated nocturnal BP almost double that solely attributable to daytime BP elevation (24.3 vs. 12.9%, P < 0.001).
Conclusion The prevalence of masked suboptimal BP control in patients with treated and well-controlled clinic BP is high. Clinic BP monitoring alone is thus inadequate to optimize BP control because many patients have an elevated nocturnal BP. These findings suggest that ABPM should become more routine to confirm BP control, especially in higher risk groups and/or those with borderline control of clinic BP.
Introduction
Masked hypertension (MH) is a term used to define people who have a normal seated clinic blood pressure (BP) but an elevated out-of-office BP, as determined by ambulatory BP monitoring (ABPM) or home BP monitoring (HBPM). Masked hypertension is the opposite of the more commonly recognized 'white coat hypertension'. Patients with MH are now known to be at particularly high risk of developing cardiovascular disease (CVD) because they often remain undetected and untreated.
Most studies on the prevalence of MH have primarily focused on 'treatment naïve' patients, prior to the diagnosis of hypertension, and many of them based the measurements on HBPM or daytime ABPM, or were of small size. This daytime definition of MH would not include people whose sole abnormality is an elevation in nocturnal BP, which some studies suggest is the strongest predictor of CVD risk compared with daytime or 24-h mean pressures. Furthermore, few studies have established the prevalence of the equivalent of MH, i.e. 'masked uncontrolled hypertension', which we have termed MUCH, in patients with treated hypertension. We use MUCH to describe treated patients in whom BP levels are sub-optimally controlled according to ABPM, but who are considered controlled to clinic BP targets by current treatment guidelines recommendations (<140/90 mmHg), which universally recommend the use of seated clinic BP to monitor BP control. MUCH has gone unrecognized because few studies have used 24-h ABPM to determine the prevalence of suboptimal BP control in seemingly well-treated patients, and there are no such studies in large cohorts of treated patients attending usual clinical practice.
The normal range for ABPM values has been defined based on data from prospective studies. For the diagnosis of hypertension, the recent UK NICE guidelines defined a daytime mean ABPM of ≥135/85 mmHg as being equivalent to the usual seated clinic BP threshold of ≥140/90 mmHg. However, ABPM also yields values for nocturnal pressures, and previous studies have suggested an ABPM-based diagnostic threshold for nocturnal hypertension as ≥120/70 and ≥130/80 mmHg for the 24-h BP average.
Despite the recognized potential for clinic BP alone to both over- and underdiagnose hypertension, to date, no guidelines have recommended the routine use of ABPM to monitor the quality of BP control because there are very little data on the quality of BP control in routine clinical practice.
The Spanish ABPM registry was established to evaluate the utility of the wider use of ABPM, and we have used this large, well-characterized population of hypertensive patients specifically to determine the frequency of MUCH in patients with treated hypertension. To our knowledge, this is the first large-scale study to evaluate and report the prevalence and characteristics of MUCH in people with seemingly well-treated hypertension.
Source...