Spanish Ambulatory Blood Pressure Monitoring Research Articles

Mortality risks in different subtypes of masked hypertension in the Spanish ambulatory blood pressure monitoring registry.

We aimed to evaluate the risks of death and cardiovascular death of different subtypes of masked hypertension, defined by either isolated daytime or nighttime blood pressure (BP) elevation, or both, compared with patients with normal both office and 24-h BP. We selected 4999 patients with masked hypertension (normal office BP and elevated 24-h BP). They were divided in three different categories: isolated daytime masked hypertension (elevated daytime BP and normal nighttime BP, 800 patients), isolated nighttime masked hypertension (elevated nighttime BP and normal daytime BP, 1069 patients) and daytime and nighttime masked hypertension (elevation of both daytime and nighttime BP, 2989). All-cause and cardiovascular death (median follow-up 9.7 years) were assessed in each of these subtypes in comparison to 10 006 patients with normal both office and 24-h BP. Hazard ratios from Cox models after adjustment for clinical confounders were used for such comparisons. Compared with patients with normal both office and 24-h BP, isolated daytime masked hypertension was not associated with an increased risk of death in models adjusted for clinical confounders [hazard ratio 1.07; 95% confidence interval (CI): 0.80-1.43]. In contrast, isolated nighttime masked hypertension (hazard ratio: 1.39; 95% CI 1.19-1.63) and daytime and nighttime masked hypertension (hazard ratio: 1.22; 95% CI 1.08-1.37) had an increased risk of death in comparison to patients with BP in the normal range. Similar results were observed for cardiovascular death. The risk of death in masked hypertension is not homogeneous and requires nocturnal BP elevation, either isolated or with daytime elevation. Isolated daytime masked hypertension is not associated with an increased risk of death.

Prognostic Relevance of Short-Term Blood Pressure Variability. The Spanish ABPM Registry.

The prognostic relevance of short-term blood pressure (BP) variability in hypertension is not clearly established. We aimed to evaluate the association of short-term BP variability, with all-cause and cardiovascular mortality in a large cohort of patients with hypertension. We selected 59 124 patients from the Spanish Ambulatory Blood Pressure Monitoring Registry from 2004 to 2014 (median follow-up: 9.7 years). Systolic and diastolic BP SD and coefficient of variation from daytime and nighttime, weighted SD, weighted coefficient of variation, average real variability (mean of differences between consecutive readings), and BP variability ratio (ratio between systolic and diastolic 24-hour SD) were calculated through baseline 24-hour ambulatory BP monitoring. Association with all-cause and cardiovascular mortality were assessed by Cox regression models adjusted for clinical confounders and BP. Patients who died during follow-up had higher values of BP variability compared with those remaining alive. In adjusted models systolic and diastolic daytime and weighted SD and coefficient of variation, average real variability, as well as systolic nighttime SD and BP variability ratio were all significantly associated with all-cause and cardiovascular mortality. Hazard ratios for 1-SD increase in the systolic components ranged from 1.05 to 1.12 for all-cause mortality and from 1.07 to 1.17 for cardiovascular mortality. A daytime SD≥13 mm Hg, a nighttime and a weighted SD≥12 mm Hg, and an average real variability ≥10 mm Hg, all systolic, were independently associated with mortality. Short-term blood pressure variability shows a relatively weak but significant association with all-cause and cardiovascular mortality in patients with hypertension.

Prevalence and Clinical Characteristics of Refractory Hypertension.

BackgroundWe aimed to estimate the prevalence of refractory hypertension (RfH) and to determine the clinical differences between these patients and resistant hypertensives (RH). Secondly, we assessed the prevalence of white‐coat RfH and clinical differences between true‐ and white‐coat RfH patients.Methods and ResultsThe present analysis was conducted on the Spanish Ambulatory Blood Pressure Monitoring Registry database containing 70 997 treated hypertensive patients. RH and RfH were defined by the presence of elevated office blood pressure (≥140 and/or 90 mm Hg) in patients treated with at least 3 (RH) and 5 (RfH) antihypertensive drugs. White‐coat RfH was defined by RfH with normal (<130/80 mm Hg) 24‐hour blood pressure. A total of 11.972 (16.9%) patients fulfilled the standard criteria of RH, and 955 (1.4%) were considered as having RfH. Compared with RH patients, those with RfH were younger, more frequently male, and after adjusting for age and sex, had increased prevalence of target organ damage, and previous cardiovascular disease. The prevalence of white coat RfH was lower than white‐coat RH (26.7% versus 37.1%, P<0.001). White‐coat RfH, in comparison with those with true RfH, showed a lower prevalence of both left ventricular hypertrophy (22% versus 29.7%; P=0.018) and microalbuminuria (28.3% versus 42.9%; P=0.047).ConclusionsThe prevalence of RfH was low and these patients had a greater cardiovascular risk profile compared with RH. One out of 4 patients with RfH have normal 24‐hour blood pressure and less target organ damage, thus indicating the important role of ambulatory blood pressure monitoring in guiding antihypertensive therapy in difficult‐to‐treat patients.

Prevalence and clinical characteristics of white-coat hypertension based on different definition criteria in untreated and treated patients.

The prevalence and associated risks of white-coat hypertension (WCH) are still a matter of debate. We aimed to assess differences in prevalence and associated conditions of WCH defined on the basis of the normality of all daytime, night-time, and 24-h blood pressure (BP), only daytime, or only 24-h BP. We selected 115 708 patients (45 020 untreated and 70 688 treated) from the Spanish Ambulatory BP Monitoring Registry. WCH was estimated in patients with elevated office BP (≥140 and/or 90 mmHg) by using normal daytime (<135/85) BP, normal 24-h BP (<130/80), or normal daytime, night-time (<120/70) and 24-h BP. Demographic and clinical data (associated risk factors and organ damage) were compared among groups. Prevalence of WCH was 41.3, 35.2, and 26.1% in untreated, and 45.8, 38.9, and 27.2% in treated patients with elevated office BP, by using the criteria of daytime, 24-h, or all ambulatory periods. Compared with the normotensive group, WCH defined by normal daytime, night-time, and 24-h BP did not significantly differ in terms of other cardiovascular risk factors or organ damage. In contrast, patients from other groups (either only normal daytime BP or 24-h BP) had significantly more prevalence of diabetes, dyslipidaemia, microalbuminuria, left ventricular hypertrophy, reduced renal function, and previous history of cardiovascular disease. Prevalence of WCH is dependent on definition criteria. Only diagnostic criteria which considers the normality of all ambulatory periods identifies patients with cardiovascular risk similar to normotensive patients. These results support using such criteria for a more accurate definition of WCH.

PP.25.27] REFRACTORY HYPERTENSION

Objective: The term refractory hypertension has been recently proposed for a small group of patients with uncontrolled hypertension despite the simultaneous use of >=5 different drug classes. To assess the prevalence of true refractory hypertension and their associated factors in comparison with resistant hypertension. Design and method: The present analysis was conducted from the Spanish Ambulatory Blood pressure monitoring (ABPM) Registry database containing 70997 treated patients who had enough information regarding office BP measurements, ABPM of good quality and complete clinical information. Blood pressure was measured at the office with a validate oscillometric device after 5-minute rest in a sitting position, and office BP estimated as the mean of 2 readings. 24h-ABPM was performed using the Spacelabs 90207 automated non-invasive oscillometric device, programmed to register BP at 20 minutes interval for the 24-hour period. Results: A total of 11.972 (16.9%) patients fulfilled the standard criteria of resistant hypertension (Office BP >= 140 and/or 90 mm Hg) despite the use of >=3 antihypertensive drugs, and 955 (1.35%) were considered as having refractory hypertension (elevated office BP despite the simultaneous use of >=5 antihypertensive agents). The prevalence of white coat (24-hour BP < 130/80 mm Hg) refractory hypertension was lower than white-coat resistant hypertension (26.7% vs 37.1%, p < 0,0001. Compared with resistant hypertension, patients with refractory hypertension had a significantly higher prevalence of diabetes mellitus (48.1% vs 33.5%; p < 0.001), and obesity (59.6% vs 51.4%; p < 0.001), and a longer duration of hypertension (13.9 vs 10.9 years; p < 0.0001). The prevalence of microalbuminuria (38.5% vs 24.5%; p < 0.0001), ECG-left ventricular hypertrophy(27.6% vs 14.9%; p < 0.0001), and previous history of a cardiovascular event (20.5% vs 14.9%;p < 0.0001) were also significantly higher in refractory, compared to resistant hypertension. Conclusions: The prevalence of refractory hypertension is low. Compared with resistant hypertension, patients with refractory hypertension have more frequently target organ damage, a higher prevalence of diabetes and a longer duration of hypertension.

24-h pulse pressure cutoff point definition by office pulse pressure in a population of Spanish older hypertensive patients

The European Guidelines on Hypertension define an office pulse pressure (PP) at least 60 mmHg in the elderly patient as asymptomatic organ damage. Our objective was to estimate the cutoff point of 24-h PP that best predicts office PP associated with higher cardiovascular risk (≥60 mmHg) in hypertensive older patients. We studied all hypertensive patients at least 60 years with a first valid ambulatory blood pressure monitoring drawn from the Spanish ambulatory blood pressure monitoring registry. Receiver operating characteristic curves were used to estimate the best 24-h PP cutoff predictor of office PP at least 60 mmHg that maximized the sum of sensitivity and specificity. We included 52 246 hypertensive patients [52.4%, female; mean age (SD) 69.0 (7.0) years]. From these, 34 530 (66.1%) patients had an office PP at least 60 mmHg. The value of 24-h PP that best predicts higher risk clinic PP is 54.9 mmHg [sensitivity: 69.2%; specificity: 70.3%; area under the receiver operating characteristic curve of 0.761 (95% confidence interval 0.756-0.765)]. Mean clinic and 24-h PPs were progressively higher as the study participants were classified at higher cardiovascular risk group. Some 20.5% of patients presented isolated office high PP and 10% a masked high 24-h PP. In a large clinical sample of older hypertensive patients, the cutoff point of 24-h PP that best predicts office PP at least 60 mmHg is 55 mmHg. In 30.5% of cases, there is a discrepancy between office PP and ambulatory 24-h PP.

Association Between High and Very High Albuminuria and Nighttime Blood Pressure: Influence of Diabetes and Chronic Kidney Disease.

Nighttime blood pressure (BP) and albuminuria are two important and independent predictors of cardiovascular morbidity and mortality. Here, we examined the quantitative differences in nighttime systolic BP (SBP) across albuminuria levels in patients with and without diabetes and chronic kidney disease. A total of 16,546 patients from the Spanish Ambulatory Blood Pressure Monitoring Registry cohort (mean age 59.6 years, 54.9% men) were analyzed. Patients were classified according to estimated glomerular filtration rate (eGFR), as ≥60 or <60 mL/min/1.73 m(2) (low eGFR), and urine albumin-to-creatinine ratio, as normoalbuminuria (<30 mg/g), high albuminuria (30-300 mg/g), or very high albuminuria (>300 mg/g). Office and 24-h BP were determined with standardized methods and conditions. High albuminuria was associated with a statistically significant and clinically substantial higher nighttime SBP (6.8 mmHg higher than with normoalbuminuria, P < 0.001). This association was particularly striking at very high albuminuria among patients with diabetes and low eGFR (16.5 mmHg, P < 0.001). Generalized linear models showed that after full adjustment for demographic, lifestyles, and clinical characteristics, nighttime SBP was 4.8 mmHg higher in patients with high albuminuria than in those with normoalbuminuria (P < 0.001), and patients with very high albuminuria had a 6.1 mmHg greater nighttime SBP than those with high albuminuria (P < 0.001). These differences were 3.8 and 3.1 mmHg, respectively, among patients without diabetes, and 6.5 and 8 mmHg among patients with diabetes (P < 0.001). Albuminuria in hypertensive patients is accompanied by quantitatively striking higher nighttime SBP, particularly in those with diabetes with very high albuminuria and low eGFR.

Ambulatory blood pressure monitoring in daily clinical practice - the Spanish ABPM Registry experience.

Many patients are hypertensive at the medical settings but show normal blood pressure out of the doctor's office, and are classified as white-coat hypertensives. On the other hand, many patients with controlled hypertension at the clinic show ambulatory blood pressure levels above the thresholds considered for an adequate blood pressure control, known as having masked hypertension. Using data from the Spanish Ambulatory Blood Pressure Monitoring Registry (Spanish ABPM Registry), a national program developed to promote the use of the ambulatory technique for hypertension management in daily practice, we have reviewed the main strengths of this approach, that is the ability to detect discrepancies of blood pressure status with respect to office blood pressure measurement, and to better assess accurate rates of hypertension control. White-coat hypertension within patients with elevated office blood pressure, and masked hypertension within office-controlled patients affected one of three patients in each office status. On the other hand, rates of ambulatory blood pressure control (50%) doubled those of office blood pressure control (25%), still remaining half the patients uncontrolled. We think that a systematic use of ambulatory blood pressure monitoring, and strategies to improve blood pressure control constitute key priorities in hypertension management.

Prevalence of Atherogenic Dyslipidemia in Spanish Hypertensive Patients and Its Relationship With Blood Pressure Control and Silent Organ Damage

Introduction and objectivesTo assess the prevalence of atherogenic dyslipidemia in hypertensive patients and its relationship with risk profile and blood pressure control. MethodsThe study included 24 351 hypertensive patients from the Spanish Ambulatory Blood Pressure Monitoring Registry. Atherogenic dyslipidemia was defined as the presence of hypertriglyceridemia (> 150mg/dL) and low levels of high-density lipoprotein cholesterol (< 40mg/dL in men and < 46mg/dL in women). Blood pressure control was assessed by office and ambulatory monitoring. ResultsAtherogenic dyslipidemia was present in 2705 patients (11.1%). Of these, 30% had hypertriglyceridemia and 21.7% had low levels of high-density lipoprotein cholesterol. Compared with patients without these risk factors, the former group were more often male (60% vs 52%), younger (57 years vs 59 years), had other risk factors and organ damage (microalbuminuria, reduced estimated glomerular filtration rate, and left ventricular hypertrophy), worse office, diurnal, and nocturnal blood pressure values (odds ratio 1.09, 1.06, and 1.10, respectively), and the lowest nocturnal blood pressure reduction (odds ratio=1.07), despite the greater use of antihypertensive drugs. ConclusionsAtherogenic dyslipidemia is present in more than 10% of hypertensive patients and is associated with other risk factors, organ damage, and poorer blood pressure control. Greater therapeutic effort is needed to reduce overall risk in these patients.

Prevalencia de dislipemia aterogénica en hipertensos españoles y su relación con el control de la presión arterial y el daño orgánico silente

Introduction and objectivesTo assess the prevalence of atherogenic dyslipidemia in hypertensive patients and its relationship with risk profile and blood pressure control. MethodsThe study included 24 351 hypertensive patients from the Spanish Ambulatory Blood Pressure Monitoring Registry. Atherogenic dyslipidemia was defined as the presence of hypertriglyceridemia (> 150mg/dL) and low levels of high-density lipoprotein cholesterol (< 40mg/dL in men and < 46mg/dL in women). Blood pressure control was assessed by office and ambulatory monitoring. ResultsAtherogenic dyslipidemia was present in 2705 patients (11.1%). Of these, 30% had hypertriglyceridemia and 21.7% had low levels of high-density lipoprotein cholesterol. Compared with patients without these risk factors, the former group were more often male (60% vs 52%), younger (57 years vs 59 years), had other risk factors and organ damage (microalbuminuria, reduced estimated glomerular filtration rate, and left ventricular hypertrophy), worse office, diurnal, and nocturnal blood pressure values (odds ratio 1.09, 1.06, and 1.10, respectively), and the lowest nocturnal blood pressure reduction (odds ratio=1.07), despite the greater use of antihypertensive drugs. ConclusionsAtherogenic dyslipidemia is present in more than 10% of hypertensive patients and is associated with other risk factors, organ damage, and poorer blood pressure control. Greater therapeutic effort is needed to reduce overall risk in these patients.Full English text available from:www.revespcardiol.org/en

Nocturnal Hypertension or Nondipping: Which Is Better Associated With the Cardiovascular Risk Profile?

Both increased night blood pressure (BP) and nondipping are associated with worse cardiovascular risk and prognosis. However, as they are often related features, their relative importance has been difficult to assess separately. In this study we address separate associations of nocturnal hypertension and nondipping with cardiovascular risk profile in treated and untreated hypertensive patients. A total of 37,096 untreated patients and 62,788 patients receiving antihypertensive treatment from the Spanish Ambulatory Blood Pressure Monitoring Registry were included. Each cohort was separated into 4 groups: group 1, night systolic blood pressure (SBP) <120 mm Hg and normal dipping (>10%); group 2, night SBP <120 mm Hg and nondipping (≤10%); group 3, nocturnal hypertension (SBP ≥120 mm Hg) and normal dipping; and group 4, nocturnal hypertension and nondipping. The smallest proportion of patients with additional cardiovascular risk factors, organ damage, and history of previous events was observed in the group with both normal night SBP and dipping, whereas those with both nocturnal hypertension and nondipping showed the largest proportion of cardiovascular risk factors and diseases. When groups showing only 1 abnormality were compared, nondipping was associated with female sex, reduced renal function, and previous cardiovascular events, whereas nocturnal hypertension was associated with male sex, smoking, and increased urinary albumin excretion. In treated patients, it was also associated with the presence of diabetes. Nondipping is related to more advanced disease (reduced renal function and clinical evidence of cardiovascular disease), whereas nocturnal hypertension is associated with albuminuria. The worst cardiovascular risk profile is present in patients exhibiting both nocturnal hypertension and nondipping.

Differences Between Office and 24-Hour Blood Pressure Control in Hypertensive Patients With CKD: A 5,693-Patient Cross-sectional Analysis From Spain

Previous studies have examined control rates of office blood pressure (BP) in chronic kidney disease (CKD). However, recent evidence suggests major discrepancies between office and 24-hour BP values in hypertensive populations. This study examined concordance/discordance between office- and ambulatory-based BP control in a large cohort of patients with CKD. Cross-sectional. 5,693 hypertensive individuals with CKD stages 1-5 from the Spanish ABPM (ambulatory BP monitoring) Registry. Thresholds of 140/90 and 130/80 mm Hg for office BP and 24-hour ambulatory BP, respectively. Age, sex, body mass index, waist circumference, hypertension duration, kidney measures, diabetes, dyslipidemia, target-organ damage, and cardiovascular comorbid conditions. Misclassification of BP control as "white-coat" hypertension (office BP ≥140/90 mm Hg, 24-hour BP <130/80 mm Hg) or masked hypertension (office BP <140/90 mm Hg, 24-hour BP ≥130/80 mm Hg). Standardized office-based BP and 24-hour ABPM. Mean age was 61.0 ± 13.9 (SD) years and 52.6% were men. The proportion with white-coat hypertension was 28.8% (36.8% of patients with office BP ≥140/90 mm Hg) and that of masked hypertension was 7.0% (but 32.1% of patients with office BP <140/90 mm Hg). Female sex, aging, obesity, and target-organ damage were associated with white-coat hypertension; aging and obesity were associated with masked hypertension. Only 21.7% and 8.1% of the CKD population had office BP <140/90 and <130/80 mm Hg, respectively. In contrast, 43.5% of individuals had average 24-hour BP <130/80 mm Hg. Cross-sectional design, longitudinal associations cannot be established. Misclassification of BP control at the office was observed in 1 of 3 hypertensive patients with CKD. Ambulatory-based control rates were far better than office-based rates. Nevertheless, the burden of uncontrolled ambulatory BP and misclassification of BP control at the office constitutes a call for wider use of ABPM to evaluate the success of hypertension treatment in patients with CKD.

Clinical differences between resistant hypertensives and patients treated and controlled with three or less drugs

Clinical characteristics of resistant hypertensive patients in comparison to controlled patients have not been fully investigated in large cohorts. The aim of the study was to evaluate clinical differences, target organ damage and ambulatory blood pressure monitoring in resistant hypertensive patients and patients controlled on three or less drugs. In December 2010, from the Spanish Ambulatory Blood Pressure Monitoring Registry, we identified 14 461 patients fulfilling criteria of resistant hypertension and 13 436 hypertensive patients controlled on three or less drugs. Clinical characteristics were compared between these two groups. Compared to controlled patients, those having resistant hypertension were older, more obese and had longer hypertension duration. They also had more frequently diabetes, dyslipidemia, reduced renal function, microalbuminuria, left-ventricular hypertrophy and previous history of cardiovascular events. In multivariate analyses, hypertension duration, obesity, abdominal obesity, left-ventricular hypertrophy, reduced estimated glomerular filtration rate, and microalbuminuria were independently associated with resistant hypertension. Resistant hypertensive patients had higher ambulatory blood pressures, but differences between office and ambulatory blood pressure (white-coat effect) were also more pronounced in this group, revealing a proportion of 40% of patients with normal 24-h blood pressure. On the contrary, values of 24-h blood pressure above 130 and/or 80 mmHg (masked hypertension) were present in 31% of apparently controlled patients. Resistant hypertension is associated with obesity, longer hypertension duration and kidney and cardiac damage. Ambulatory blood pressure monitoring reveals that white-coat hypertension is common among resistant hypertensive patients, as well as is masked hypertension among apparently controlled patients.

INCREASE IN TREATMENT-REFRACTORY HYPERTENSION: PROGRESS IN CURRENT TREATMENT BY PRIMARY CARE

The prevalence of treatment resistant hypertension (TRH) defined as blood pressure (BP) uncontrolled on ≥3 antihypertensive medications in optimal doses, preferably including a diuretic, or controlled on ≥4 BP medications is unknown. Clinical trials suggest that 20–30% of hypertensives have TRH. Using U.S. NHANES data, the prevalence of apparent (a) TRH among treated, uncontrolled (BP ≥140/≥90 mmHg) individuals rose from 15.9% in 1988–1994 to 28.0% in 2005–2008; ‘aTRH’ is used, since medication dose, adherence, and measurement artefacts are unavailable in NHANES. About 30–50% of patients with aTRH have pseudoresistance, i.e., inaccurate BP, non-representative BP (‘office’ effect), or non-adherence. The Spanish Ambulatory BP Monitoring Registry reported that 3 in 8 patients with aTRH have ‘office’ resistance with normal ambulatory BP. Primary care clinicians can manage most TRH patients. First, primary care clinicians verify whether the regimen is appropriate, patient adherence, and carefully measured office readings are elevated. Second, document BP values out-of-office. Third, for the 50–70% with ‘true’ TRH, identify contributing lifestyle factors and facilitate improved health behaviors. Fourth, minimize prescription and ‘over-the-counter’ medications that raise BP. Fifth, screen for suspected secondary causes of hypertension. Sixth, use efficacious strategies for improving the antihypertensive regimen, e.g., optimizing diuretic therapy, adding an aldosterone antagonist, renin- or hemodynamic-guided therapeutics, and α,β-receptor blockade. This approach should control most patients with ‘true’ TRH. Seventh, for patients remaining uncontrolled, referral to a Clinical Hypertension Specialist is recommended. Primary care clinicians can improve community BP control and outcomes with a systematic approach to managing patients with TRH.

Response to Unmasking True Resistant Hypertension: Is the Real-World Resistance Just Revealed?

We thank Thomopoulos and Tsioufis1 for their interest in our article2 and also for their positive feedback and criticism. We will try to answer directly to the 3 points raised in their letter. First, we would like to clarify our analyses regarding treatment posology. Although, in the protocol of the Spanish Ambulatory Blood Pressure Monitoring Registry, details of treatment posology were collected on a 3-category scheme, results from this cohort of patients with resistant hypertension indicated that only 41 patients (0.5% of the cohort) received part of their …

Unmasking True Resistant Hypertension: Is the Real-World Resistance Just Revealed?

To the Editor: We read with interest the well-written article by de la Sierra et al1 aiming to estimate the prevalence of resistant hypertension (RH) in a large cohort of treated hypertensive patients, most of them in the primary care setting, from the Spanish Ambulatory Blood Pressure Monitoring Registry. The authors have elegantly shown that RH was present in ≈12% of patients, but among these patients, only two thirds had true RH. The remaining one third of the patients demonstrated normal ambulatory blood pressure, which suggests a white-coat RH phenotype. Although both the study protocol and the retrospective analysis …

Clinical Features of 8295 Patients With Resistant Hypertension Classified on the Basis of Ambulatory Blood Pressure Monitoring

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.

AMBULATORY BLOOD PRESSURE VARIABILITY IN NORMOTENSION AND IN WHITE COAT, MASKED AND SUSTAINED HYPERTENSION. DATA FROM THE SPANISH AMBULATORY BLOOD PRESSURE REGISTRY: PP.3.100

Objective: Based on their office and ambulatory blood pressure (BP), subjects can be classified as normotensive (NT), white coat, masked or sustained hypertensive (WCHT, MHT, SHT, respectively). It is not clear whether these categories are associated with differences in the degree of daily life BP variability (V). Aim of the present study was to assess this issue in a large group of subjects from the Spanish Ambulatory Blood Pressure Monitoring Registry. Methods: We analyzed ambulatory BP recordings (Spacelabs 90207) obtained in 18395 subjects (age: 52.8 ± 14.7 years, 55% males) not on antihypertensive medication for at least 2 weeks. Based on the accepted cutoffs for office (<140/90mmHg) and 24 h (<130/80mmHg) BP normality, subjects were classified as NT, WCHT, MHT and SHT. BPV was quantified as 24 h standard deviation (SD), weighted 24 h (wSD) and average real variability (ARV: average absolute BP difference between successive readings) for systolic (S) and diastolic (D)BP. The difference in BPV between BP categories was assessed by an ANCOVA model adjusted for age, BMI, gender, smoking, diabetes, dyslipidemia, previous cardiovascular diseases, renal insufficiency and average 24 h SBP or DBP as appropriate. Results: The distribution of subjects was as follows: 15.8%, 30.0%, 6.4% and 47.8% in NT, WCHT, MHT and SHT groups, respectively. The adjusted estimates of 24 h SBPV and DBPV in the four groups are shown in Table. Compared to NT, night-time SBP SD was similarly elevated in MHT and SHT (p < 0.001), but not in WCHT.Conclusions: Compared to NT, after adjusting for mean BP we found an increased 24 h BPV in WCHT similar to that observed in SHT, with smaller differences in MHT. Conversely, night-time BPV was increased in MHT and in SHT but not in WCHT. Our data suggest that increased office BP is associated with higher BP reactivity to daily life stimuli, irrespective of differences in average out-of-office BP. These findings may be relevant when considering the higher cardiovascular risk reported by some studies in WCHT.

Evidencias generadas por el proyecto CARDIORISC

After five years of work, the Spanish Ambulatory Blood Pressure Monitoring Registry, a project promoted by the Spanish Society of Hypertension-Spanish League for the Fight against Hypertension, has achieved its triple objective as a clinical, educational and research project. Many health professionals, both physicians and nurses, have incorporated 24-hour ambulatory blood pressure monitoring into their daily clinical practice, both in the diagnosis and follow-up of patients with hypertension, which has enabled the creation of the largest database on ambulatory blood pressure monitoring in the world. The present article aims to provide a comprehensive review of the evidence generated by this project in recent years, much of which has been presented at various meetings and published in national and international journals.

Discrepancies between Office and Ambulatory Blood Pressure: Clinical Implications

Background Recent trials have documented no benefit from small reductions in blood pressure measured in the clinical office. However, ambulatory blood pressure is a better predictor of cardiovascular events than office-based blood pressure. We assessed control of ambulatory blood pressure in treated hypertensive patients at high cardiovascular risk. Methods We selected 4729 patients from the Spanish Ambulatory Blood Pressure Monitoring Registry. Patients were aged ≥55 years and presented with at least one of the following co-morbidities: coronary heart disease, stroke, and diabetes with end-organ damage. An average of 2 measures of blood pressure in the office was used for analyses. Also, 24-hour ambulatory blood pressure was recorded at 20-minute intervals with a SpaceLabs 90207 device. Results Patients had a mean age of 69.6 (±8.2) years, and 60.8% of them were male. Average time from the diagnosis of hypertension to recruitment into the Registry was 10.9 (±8.4) years. Mean blood pressure in the office was 152.3/82.3 mm Hg, and mean 24-hour ambulatory blood pressure was 133.3/72.4 mm Hg. About 60% of patients with an office-pressure of 130-139/85-89 mm Hg, 42.4% with office-pressure of 140-159/90-99 mm Hg, and 23.3% with office-pressure ≥160/100 mm Hg were actually normotensive, according to 24-hour ambulatory blood pressure criteria (<130/80 mm Hg). Conclusion We suggest that the lack of benefit of antihypertensive therapy in some trials may partly be due to some patients having normal pressure at trial baseline. Ambulatory monitoring of blood pressure may allow for a better assessment of trial eligibility.