We aimed to estimate the prevalence of resistant hypertension through both office and ambulatory blood pressure monitoring in a large cohort of treated hypertensive patients from the Spanish Ambulatory Blood Pressure Monitoring Registry. In addition, we also compared clinical features of patients with true or white-coat–resistant hypertension. In December 2009, we identified 68 045 treated patients with complete information for this analysis. Among them, 8295 (12.2% of the database) had resistant hypertension (office blood pressure ≥140 and/or 90 mm Hg while being treated with ≥3 antihypertensive drugs, 1 of them being a diuretic). After ambulatory blood pressure monitoring, 62.5% of patients were classified as true resistant hypertensives, the remaining 37.5% having white-coat resistance. The former group was younger, more frequently men, with a longer duration of hypertension and a worse cardiovascular risk profile. The group included larger proportions of smokers, diabetics, target organ damage (including left ventricular hypertrophy, impaired renal function, and microalbuminuria), and documented cardiovascular disease. Moreover, true resistant hypertensives exhibited in a greater proportion a riser pattern (22% versus 18%; P <0.001). In conclusion, this study first reports the prevalence of resistant hypertension in a large cohort of patients in usual daily practice. Resistant hypertension is present in 12% of the treated hypertensive population, but among them more than one third have normal ambulatory blood pressure. A worse risk profile is associated with true resistant hypertension, but this association is weak, thus making it necessary to assess ambulatory blood pressure monitoring for a correct diagnosis and management.

Evidence for the influence of ambulatory blood pressure on prognosis derives mainly from population-based studies and a few relatively small clinical investigations. This study examined the associations of blood pressure measured in the clinic (clinic blood pressure) and 24-hour ambulatory blood pressure with all-cause and cardiovascular mortality in a large cohort of patients in primary care.

Ambulatory blood pressure (BP) monitoring has become useful in the diagnosis and management of hypertensive individuals. In addition to 24-hour values, the circadian variation of BP adds prognostic significance in predicting cardiovascular outcome. However, the magnitude of circadian BP patterns in large studies has hardly been noticed. Our aims were to determine the prevalence of circadian BP patterns and to assess clinical conditions associated with the nondipping status in groups of both treated and untreated hypertensive subjects, studied separately. Clinical data and 24-hour ambulatory BP monitoring were obtained from 42 947 hypertensive patients included in the Spanish Society of Hypertension Ambulatory Blood Pressure Monitoring Registry. They were 8384 previously untreated and 34 563 treated hypertensives. Twenty-four-hour ambulatory BP monitoring was performed with an oscillometric device (SpaceLabs 90207). A nondipping pattern was defined when nocturnal systolic BP dip was <10% of daytime systolic BP. The prevalence of nondipping was 41% in the untreated group and 53% in treated patients. In both groups, advanced age, obesity, diabetes mellitus, and overt cardiovascular or renal disease were associated with a blunted nocturnal BP decline ( P <0.001). In treated patients, nondipping was associated with the use of a higher number of antihypertensive drugs but not with the time of the day at which antihypertensive drugs were administered. In conclusion, a blunted nocturnal BP dip (the nondipping pattern) is common in hypertensive patients. A clinical pattern of high cardiovascular risk is associated with nondipping, suggesting that the blunted nocturnal BP dip may be merely a marker of high cardiovascular risk.

Hypertensive emergencies are those situations where very high blood pressure (BP) values are associated with acute organ damage, and therefore, require immediate, but careful, BP reduction. The type of acute organ damage is the principal determinant of: (i) the drug of choice, (ii) the target BP, and (iii) the timeframe in which BP should be lowered. Key target organs are the heart, retina, brain, kidneys, and large arteries. Patients who lack acute hypertension-mediated end organ damage do not have a hypertensive emergency and can usually be treated with oral BP-lowering agents and usually discharged after a brief period of observation.

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. 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). 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.

Goal blood pressure (BP) was defined by the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC-VI) and the World Health Organization–International Society of Hypertension (WHO/ISH) as <140 mm Hg systolic and <90 mm Hg diastolic for the general and <130 mm Hg systolic and <85 mm Hg diastolic for special high-risk populations. However, there are few reports that address BP control among special subgroups of hypertensives by reference to targeted BP. We therefore conducted a study to evaluate BP control of 4049 hypertensives in 47 hospital-based hypertension units in Spain. Overall, 42% of patients achieved goal BP (<140 mm Hg systolic and <90 mm Hg diastolic). Only 13% of diabetic patients and 17% of those with renal disease achieved the BP goal (<130 mm Hg systolic and <85 mm Hg diastolic), and only 10% and 12%, respectively, achieved the even more rigorous goal (<130 mm Hg systolic and <80 mm Hg diastolic). Likewise, only 18% of patients in JNC-VI risk group C and 17% of WHO/ISH high-risk patients attained a goal BP <130 mm Hg systolic and <85 mm Hg diastolic. BP control (<125 mm Hg systolic and 1 g/d. Poorer BP control was observed among patients at high risk, with diabetes, renal disease, or obesity, than in lower-risk groups. BP control was lower for systolic than for diastolic BP. In >50% of uncontrolled patients, no measures were taken by doctors to optimize pharmacologic treatment, and approximately one-third of patients were still using drug monotherapy. Control of BP, particularly of systolic BP, is still far from optimal in hospital-based hypertension units. Patients at high risk, with diabetes or proteinuria, warrant focused attention. Moreover, a more aggressive behavior of doctors treating uncontrolled hypertension is needed.