M. Gorostidi

Relationship between Clinic and Ambulatory Blood-Pressure Measurements and Mortality

Background 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. Methods We analyzed data from a registry‐based, multicenter, national cohort that included 63,910 adults recruited from 2004 through 2014 in Spain. Clinic and 24‐hour ambulatory blood‐pressure data were examined in the following categories: sustained hypertension (elevated clinic and elevated 24‐hour ambulatory blood pressure), “white‐coat” hypertension (elevated clinic and normal 24‐hour ambulatory blood pressure), masked hypertension (normal clinic and elevated 24‐hour ambulatory blood pressure), and normotension (normal clinic and normal 24‐hour ambulatory blood pressure). Analyses were conducted with Cox regression models, adjusted for clinic and 24‐hour ambulatory blood pressures and for confounders. Results During a median follow‐up of 4.7 years, 3808 patients died from any cause, and 1295 of these patients died from cardiovascular causes. In a model that included both 24‐hour and clinic measurements, 24‐hour systolic pressure was more strongly associated with all‐cause mortality (hazard ratio, 1.58 per 1‐SD increase in pressure; 95% confidence interval [CI], 1.56 to 1.60, after adjustment for clinic blood pressure) than the clinic systolic pressure (hazard ratio, 1.02; 95% CI, 1.00 to 1.04, after adjustment for 24‐hour blood pressure). Corresponding hazard ratios per 1‐SD increase in pressure were 1.55 (95% CI, 1.53 to 1.57, after adjustment for clinic and daytime blood pressures) for nighttime ambulatory systolic pressure and 1.54 (95% CI, 1.52 to 1.56, after adjustment for clinic and nighttime blood pressures) for daytime ambulatory systolic pressure. These relationships were consistent across subgroups of age, sex, and status with respect to obesity, diabetes, cardiovascular disease, and antihypertensive treatment. Masked hypertension was more strongly associated with all‐cause mortality (hazard ratio, 2.83; 95% CI, 2.12 to 3.79) than sustained hypertension (hazard ratio, 1.80; 95% CI, 1.41 to 2.31) or white‐coat hypertension (hazard ratio, 1.79; 95% CI, 1.38 to 2.32). Results for cardiovascular mortality were similar to those for all‐cause mortality. Conclusions Ambulatory blood‐pressure measurements were a stronger predictor of all‐cause and cardiovascular mortality than clinic blood‐pressure measurements. White‐coat hypertension was not benign, and masked hypertension was associated with a greater risk of death than sustained hypertension. (Funded by the Spanish Society of Hypertension and others.)

Control of hypertension in coronary heart disease.

This observational study investigates, for the first time, the actual or out-of-office control of hypertension among coronary heart disease (CHD) patients, by using 24-h ambulatory BP monitoring (ABPM). We used the Spanish Society of Hypertension ABPM Registry, based on a large-scale network of primary-care physicians consecutively recruiting hypertensive patients with conventional clinical indications for ABPM. The average of two office BP measurements was used for analyses. Thereafter, 24-h ABPM was performed, using a SpaceLabs 90207 device. Out-of-office control of hypertension among 2434 treated essential hypertensive patients with clinically documented CHD was much higher (46.4%) than in-office BP control (28.7%). This considerable difference was partly due to the presence of 25.2% of patients with office resistance, i.e., normal ambulatory BP but with high office BP despite treatment. Although further efforts in controlling BP are needed in CHD patients, physicians should be also comforted by BP results better than previously believed based on office data.

Heart rate and heart rate variability in resistant versus controlled hypertension and in true versus white-coat resistance.

Sympathetic nervous system has an important role in resistant hypertension. Heart rate (HR) is a marker of sympathetic activity, but its association with resistant hypertension has not been assessed. We aimed to evaluate differences in HR values and variability between resistant and controlled patients and between true and white-coat resistant hypertensives (RHs). We compared office and ambulatory HR, nocturnal dip and s.d. in 14u2009627 RHs versus 11u2009951 controlled patients (on ⩽3 drugs) and in 8730 true (24u2009h blood pressure (BP)⩾130 and/or 80u2009mmu2009Hg) versus 4825 white-coat (24-h BP<130/80u2009mmu2009Hg) RHs. After adjusting for age, gender, body mass index, diabetes status and beta blocker use, HR values and variability were significantly elevated in resistant versus controlled patients and in true versus white-coat RHs. In logistic regression models, after adjustment for confounders, office HR (odds ratio for each increase in tertile: 1.337; 95% confidence interval: 1.287–1.388; P<0.001), nocturnal dip (0.958; 0.918–0.999; P=0.035) and night time s.d. (1.115; 1.057–1.177; P=0.013) were all significantly associated with the presence of resistant hypertension. Moreover, night time HR (1.160; 1.065–1.265; P<0.001), nocturnal dip (0.876; 0.830–0.925; P<0.001) and 24-h s.d. (1.148; 1.092–1.207; P<0.001) were all significantly associated with true resistant hypertension. In conclusion, both increased HR and variability are associated with resistant hypertension and with true resistance. These suggest the involvement of the sympathetic nervous system in the development of resistance to antihypertensive treatment.

Hipertensión arterial nocturna

Resumen Las alteraciones de la presion arterial nocturna, tanto absolutas (hipertension arterial nocturna) como relativas (patron circadiano no dipper ), son un hallazgo frecuente entre los pacientes con hipertension arterial. Estas anomalias se relacionan con un riesgo aumentado de dano vascular subclinico y de complicaciones cardiovasculares. La monitorizacion ambulatoria de la presion arterial es una herramienta basica en la evaluacion de la presion arterial nocturna. En la presente revision se tratan tanto aspectos descriptivos y epidemiologicos de la presion arterial nocturna como posibles abordajes terapeuticos. Estos incluyen desde el tratamiento antihipertensivo clasico hasta alternativas recientes, como la cronoterapia o el bloqueo optimo del sistema renina-angiotensina.

EFFECTS OF AIR POLLUTION IN 24H AMBULATORY BLOOD PRESSURE MONITORING

Objective: INTRODUCTION: Air particulate matters and nitrogen and sulfur dioxide are the most worrying environmental pollutants, with the greatest impact on public health. There are studies that relate atmospheric pollution with the increase in office blood pressure, but there is no study that relates air pollution with 24u200ah ambulatory blood pressure (ABP). Objective: To know the relationship between ABP and classic atmospheric pollutants (PM10, PM2,5, NO2 and SO2) and the most recent measurement (ultrafine particles, PUF). Design and method: Observational study of temporary and geographical measures of polluants in individual patients (case-time series design) in centers of Primary Care and Units of Hypertension of a large urban area. Untreatedu200a>u200a18 years hypertensive patients were included, with a first valid ABP monitoring (ABPM) conducted between 2005–2014 and with at least one atmospheric pollution reader atu200a<u200a3u200akm of radius of the center where the ABPM was performed. Analysis of regression of temporal series adjusted by individual variables (sociodemographic and risk factors) and ecological (environmental temperature). Results: Sample of 2,888 hypertensive patients. Mean age of 54.3 (SD 14,6) years and 50,1% are women. Body Mass Index (BMI) 28.8u200akg/m2 (SD 6.4) and 16.9% of the sample smokes. Baseline 24u200ah ABPM 128.0 (12.7)/77.4 (9.7) mmHg. For each increase of 10u200amg/m3 of PM10 an increase of 1.37 mmHg in 24u200ah diastolicBP (DBP) and 1.48 mmHg in daytime-DBP was observed, statistically significant. For each increase of 1u200amg/m3 of PUF 24u200ah DBP increases in 1.46 mmHg and daytime-DBP in 1.56 mmHg, statistically significant. The calculation was adjusted by temporal variables of ABPM measures, sociodemographic variables and risk factors, and by environmental temperature. No association was found with any of the two pollutants and nighttime-DBP. No statistical relationship was detected between the PM2.5, NO2 and SO2 pollutants and ABPM, nor between any air pollutants and the office BP. Conclusions: The increase in the atmospheric concentration of PM10 and PUF particles the day prior to ABPM is significantly associated with an increase in 24u200ah DBP and daytime-DBP.

CONCORDANCE OF BP CONTROL ASSESSED BY OFFICE BP AND BY ABPM IN A LARGE COHORT OF TREATED HYPERTENSIVES: PP.14.06

Objective: To examine the concordance of blood pressure (BP) control by means of both office measurements and ambulatory BP monitoring (ABPM), in a large cohort of treated hypertensives from the Spanish Society of Hypertension ABPM Registry. Methods: A total of 43,499 hypertensives were analyzed. Office BP control was defined when BP <140/90 mmHg. Ambulatory BP control was considered by means of 3 different criteria: daytime BP <135/85 mmHg, 24-h BP <130/80 mmHg, and nightime BP <120/70 mmHg. Clinical characteristics were compared between patients with daytime BP below or above 135/85 mmHg. Results: Office BP control was 22.7%, daytime BP control was 52.0%, 24-h BP control was 44.8%, and nighttime BP control was 39.7%. Concordant control of BP was present in 17.4%, 15.7%, and 12.9%, by the 3 different criteria. The main source of difference between office and ABPM was the proportion of patients with isolated office resistance, the proportion of which, using the 3 aforementioned criteria was 34.5%, 29.1%, and 26.8%, respectively. When compared to patients with normal ABPM values, the presence of elevated daytime BP (higher than 135/85 mmHg) was associated (p < 0.001 for all comparisons) with male gender (57.5% vs 47.7%), diabetes (25.1% vs 20.9%), smoking (17.5% vs 12.5%), left ventricular hypertrophy on EKG (11.1 vs 9.1), and chronic kidney disease (3.0% vs 2.0%). Conclusions: BP control in the treated hypertensive population by using ABPM is twice as observed by office measurements. The proportion of patients with isolated office resistance (white coat) is relatively large. Normal values of ABPM in treated patients are more frequent in women, nondiabetic, and nonsmokers subjects, as well as in those without organ damage.

IMPROVEMENT IN HYPERTENSION CONTROL AFTER A 2-YEAR PARTICIPATION IN A WEB-BASED PROGRAM ON HIGH BP MANAGEMENT: 6C.01

Objective: To examine changes in hypertension control reported by physicians participating in a web-based project for management of patients with high BP. Methods: We selected physicians participating in the Spanish Society of Hypertension ABPM Registry, each one recruiting >20 subjects both in 2005 (group 1 or G1) and 2007 (group 2 or G2) (n = 71). Data between both groups were compared. Cases with repeated ABPM were discarded. Office BP was considered as controlled when <140/90 mmHg and ambulatory BP was considered as controlled when 24-h BP <130/80 mmHg. Results: G1 and G2 included 4,158 and 3,253 patients respectively. Age (62.3 vs 62.7 years), duration of hypertension (8.3 vs 8.1 years), body mass index (29.5 vs 29.3 kg/m2), presence of at least one additional cardiovascular risk factor (91.1% vs 90.3%), prevalence of diabetes (21.9% vs 20.7%), and prevalence of established cardiovascular disease (16.8 vs 15.6%) were similar in both groups. Male sex was 49.0% in G1 and 51.6% in G2, p = 0.03. Office BP was 151.2/86.6 mmHg in G1 and 146.8/84.2 mmHg in G2 (p < 0.001), and control rates were 22.8% and 27.9% respectively (p < 0.001). Mean 24-h BP was 130.4/75.4 mmHg in G1 and 129.2/74.7 mmHg in G2 (p < 0.01), and ambulatory control rates 45.1% and 48.0% respectively (p = 0.022). Combination antihypertensive therapy was more frequently used in 2007 (68.5%) than in 2005 (63.3%), p < 0.001. Conclusions: A modest improvement in 2-year hypertension control rate was observed in patients attended by participant physicians in this web-based ABPM registry. Programs designed to help physicians in daily management of hypertensive patients may be useful for ameliorating hypertension control.

PREVALENCE OF MASKED HYPERTENSION IN SUBJECTS WITH HIGH NORMAL BLOOD PRESSURE: PP.3.98

Objective: To estimate the prevalence of masked hypertension in subjects with high normal blood pressure (BP). Methods: We analyzed data from untreated individuals included in the Spanish Society of Hypertension ABPM Registry (whole sample number 68,045). High normal BP was defined following current guidelines when office systolic BP was 130–139 mmHg and diastolic BP was 85–89 mmHg. A series of demographic and clinical variables were collected. Definitions and risk stratification followed 2007 ESH-ESC guidelines. ABPM was performed under standardized conditions. Masked hypertension was diagnosed when mean 24-h systolic BP = or > 130 mmHg and/or 24-h diastolic BP = or >80 mmHg. Results: We identified 3,199 untreated subjects with high normal BP. Mean (SD) age was 51.2 (15.1) years, 53.6% were men, and 26.4% were obese (body mass index ≥30 kg/m2). Mean (SD) office BP was 132.5 (5.2)/81.5 (6.3) mmHg and mean (SD) 24-h ambulatory BP was 123.9 (10,4)/75.8 (8,2) mmHg. Prevalence (95%CI) of masked hypertension was 39.5% (37.8–41.2). Subjects with masked hypertension showed a 24.5 % prevalence of high cardiovascular risk. With respect to individuals with ambulatory normotension, subjects with masked hypertension were overweighted, more frequently smokers, and showed a higher prevalence of a riser profile of nocturnal BP (p < 0.05 for all comparisons). Prevalence of documented target organ damage and established cardiovascular disease was similar in patients with masked hypertension and subjects with ambulatory normotension. Conclusions: Masked hypertension was present in 4 of 10 subjects with high-normal BP. This proportion and the potential high-risk profile of these individuals should encourage the detection of masked hypertension in subjects with high-normal BP.

MEASURING CARDIOVASCULAR RISK IN NORMOTENSIVE PEOPLE: IMPACT OF A NON DIPPER PATTERN OF BLOOD PRESSURE: PP.3.122

Objective: To assess the impact of a non-dipper pattern of blood pressure (BP) on vascular risk in normotensive people. Methods: We analyzed data from 10,358 non-treated subjects from the Spanish Society of Hypertension Ambulatory BP Monitoring (ABPM) Registry (total sample n = 102,615) having 24-h BP <130/80 mmHg. We compared total cardiovascular risk between subjects with a non dipping BP and subjects with a dipping BP. Risk stratification was assessed following the 2007 ESH-ESC guidelines. ABPM was performed under standardized conditions and the conventional definition of a NDBP was applied. Results: Mean age was 53.0 years, 53.7% were women, and body mass index was 28.0 kg/m2. A total of 5,572 subjects (53.8%) showed a dipping pattern and 4,786 (46.2%) were non-dippers. With respect to dippers, individuals with a non-dipper profile were older (56.2 vs 50.3 years), more frequently women (55.3% vs 52.4%), had a lower daytime BP (119.4/71.9 vs 123.9/76.4 mmHg), and a higher nighttime BP (115.0/65.6 vs 105.0/60.4 mmHg) (p < 0.001 for all). Prevalences of accompanying risk factors were higher in non-dippers (overweight-obesity 91.0% vs 84.9%, diabetes 14.0% vs 9.6%, dyslipidaemia 30.9% vs 27.2%, p < 0.001 for all) with the exception of smoking (14.5% vs 19.7%, p < 0.001). Prevalence of documented target organ damage (6.7% vs 3.4%, p < 0.001) and established cardiovascular disease (7.0% vs 3.5%, p < 0.001) was also higher in non-dippers. A high or very high added cardiovascular risk was also more prevalent in this group (25.6% vs 19.3%, p < 0.001). Conclusions: Normotensive subjects with a non-dipping BP, in comparison to dippers, showed an unfavorable cardiovascular risk profile. A non-dipping BP could identify normotensive subjects at risk of developing cardiovascular damage and could be considered as a marker of cardiovascular risk in this population.

RELATIONSHIP BETWEEN NOCTURNAL BLOOD PRESSURE PATTERNS AND DAYTIME BLOOD PRESSURE VARIABILITY IN THE SPANISH AMBULATORY BLOOD PRESSURE MONITORING REGISTRY: 8C.05

Objective: Different abnormal patterns of nocturnal blood pressure (BP) including nocturnal hypertension, absent or excessive night-time BP fall, as well as increased short-term BP variability have been reported to be associated with an increased risk of cardiovascular events. However, it is not clear whether any relationship exists between different nocturnal BP patterns and daytime BP variability. The aim of the present study was to address this issue taking advantage of the large number of subjects included in the Spanish Ambulatory Blood Pressure Monitoring Registry. Methods: We studied 18405 subjects (mean age: 52.7 ± 14.3 years, male 54%) not on antihypertensive medication for at least 2 weeks. Ambulatory BP monitoring was performed with Spacelabs 90207 devices. BP variability was quantified as standard deviation (SD) of daytime (10 a.m.-10 p.m.) values. Data were analyzed by different models, subdividing subjects into: 1) categories of day/night systolic(S) BP pattern [risers (R): < 0% nocturnal SBP fall, nondippers: 0–5% (ND1) and 5–10% (ND2), dippers (D): 10–20%, extreme dippers (ED): >20%] and 2) quintiles of mean night-time (midnight-6 a.m.) SBP. The differences between categories were assessed by means of an ANCOVA model adjusted for age, BMI, gender, smoking, diabetes, dyslipidemia, previous cardiovascular disease, renal insufficiency and mean 24 h SBP (Model 1) or mean awake SBP (Model 2). Post hoc analysis with Bonferroni correction was used for multiple comparisons. Results: Significant differences in daytime SBP SD were found between day/night SBP fall categories (p < 0.0001) and between night-time SBP quintiles (p < 0.0001) (see Figure). Conclusions: Untreated subjects with very high or very low nocturnal BP, as well as with “riser” and “extreme-dipper” SBP profile show increased short-term BP variability during the awake period even after adjustment for major confounders. This relationship may reflect an increased sympathetic activity in these subjects. Studies on the clinical relevance of these ambulatory BP patterns should thus not disregard such an association. Figure 1. No caption available.