Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal).

Hitherto, diagnosis of hypertension in sub-Saharan Africa was largely based on conventional office blood pressure (BP). Data on the prevalence of masked hypertension (MH) in this region is scarce. Among individuals with normal office BP (<140/90 mm Hg), we compared the prevalence and determinants of MH diagnosed with self-monitored home blood pressure (≥135/85 mm Hg) among 293 Nigerians with a reference population consisting of 3615 subjects enrolled in the International Database on Home Blood Pressure in Relation to Cardiovascular Outcomes. In the reference population, the prevalence of MH was 14.6% overall and 11.1% and 39.6% in untreated and treated participants, respectively. Among Nigerians, the prevalence standardized to the sex and age distribution of the reference population was similar with rates of 14.4%, 8.6%, and 34.6%, respectively. The mutually adjusted odds ratios of having MH in Nigerians were 2.34 (95% confidence interval, 1.39-3.94) for a 10-year higher age, 1.92 (1.11-3.31) and 1.70 (1.14-2.53) for 10- or 5-mm Hg increments in systolic or diastolic office BP, and 3.05 (1.08-8.55) for being on antihypertensive therapy. The corresponding estimates in the reference population were similar with odds ratios of 1.80 (1.62-2.01), 1.64 (1.45-1.87), 1.13 (1.05-1.22), and 2.84 (2.21-3.64), respectively. In conclusion, MH is as common in Nigerians as in other populations with older age and higher levels of office BP being major risk factors. A significant proportion of true hypertensive subjects therefore remains undetected based on office BP, which is particularly relevant in sub-Saharan Africa, where hypertension is now a major cause of death.

Home blood pressure (HBP) measurements are known to be lower than conventional office blood pressure (OBP) measurements. However, this difference might not be consistent across the entire age range and has not been adequately investigated. We assessed the relationship between OBP and HBP with increasing age using the International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO). OBP, HBP and their difference were assessed across different decades of age. A total of 5689 untreated subjects aged 18-97 years, who had at least two OBP and HBP measurements, were included. Systolic OBP and HBP increased across older age categories (from 112 to 142 mm Hg and from 109 to 136 mm Hg, respectively), with OBP being higher than HBP by ∼7 mm Hg in subjects aged >30 years and lesser in younger subjects (P=0.001). Both diastolic OBP and HBP increased until the age of ∼50 years (from 71 to 79 mm Hg and from 66 to 76 mm Hg, respectively), with OBP being consistently higher than HBP and a trend toward a decreased OBP-HBP difference with aging (P<0.001). Determinants of a larger OBP-HBP difference were younger age, sustained hypertension, nonsmoking and negative cardiovascular disease history. These data suggest that in the general adult population, HBP is consistently lower than OBP across all the decades, but their difference might vary between age groups. Further research is needed to confirm these findings in younger and older subjects and in hypertensive individuals.

Accumulating evidence suggests that central blood pressure (BP) may reflect the hemodynamic stress on target organs more accurately than brachial BP. A systematic review assessing the relationship of central versus brachial BP with preclinical target-organ damage was performed. Meta-analysis of cross-sectional data showed that central compared with brachial systolic BP was more closely associated with (1) left ventricular mass index (12 studies, n=6431; weighted age [SD], 49.9 [13.1] years; 51% hypertensives): pooled correlation coefficients r=0.30; 95% confidence interval (CI), 0.23-0.37 versus r=0.26; 95% CI, 0.19-0.33, respectively; P<0.01 for difference; (2) carotid intima-media thickness (7 studies, n=6136; weighted age, 55.6 [13.2] years; 48% hypertensives): r=0.27; 95% CI, 0.19-0.34 versus r=0.23; 95% CI, 0.16-0.30, respectively; P<0.01 for difference; (3) pulse-wave velocity (14 studies, n=3699; weighted age, 53.9 [13.3] years; 53% hypertensives): r=0.42; 95% CI, 0.37-0.47 versus r=0.39; 95% CI, 0.33-0.45, respectively; P<0.01 for difference. Four studies assessing urine albumin excretion (n=3718; weighted age, 56.4 [5] years; 69% hypertensives) reported similar correlations (P=not significant) with central (r=0.22; 95% CI, 0.14-0.29) and brachial systolic BP (r=0.22; 95% CI, 0.12-0.32). Similar findings were observed for central compared with brachial pulse pressure in terms of relationship with target-organ damage. Metaregression analyses did not reveal any significant effect of age. In conclusion, central compared with brachial BP seems to be more strongly associated with most of the investigated indices of preclinical organ damage.

Several guidelines recommend opportunistic screening for atrial fibrillation (AF) in subjects aged ≥ 65 years using pulse palpation during routine blood pressure (BP) measurement. However, this method has limited diagnostic accuracy. A specific algorithm for AF detection during automated BP measurement was developed and implemented in a novel oscillometric device (Microlife WatchBP Home-A). In 2013, the UK National Institute for Health and Care Excellence (NICE) recommended this device for AF screening during routine office BP measurement in primary care in subjects ≥ 65 years. A review and meta-analysis of the evidence on the diagnostic accuracy of this algorithm were performed. Six studies (n=2332) investigated the accuracy of AF detection using the Microlife BP monitor and estimated a pooled sensitivity at 0.98 (95% CI 0.95, 1.00) and specificity 0.92 (0.88, 0.96). Analysis of 4 studies (n=1126) showed more readings to improve specificity (from 0.86 to 0.91) and sensitivity (from 0.97 to 0.99). Taking 3 sequential readings with at least 2 detecting AF gave the highest diagnostic accuracy. A single study (n=139) of paroxysmal AF screening with home BP monitoring (3316 days) showed sensitivity 99% and specificity 93%. Another study (n=46) of AF screening with 24h ambulatory BP monitoring showed that AF detected in >15% of all readings has high probability of AF diagnosis requiring confirmation by 24h electrocardiography. AF detection with routine automated BP measurement is a reliable screening tool in the elderly, which requires confirmation by electrocardiography. Paroxysmal AF might also be detected by routine automated home or ambulatory BP monitoring.

To generate outcome-driven thresholds for home blood pressure (BP) in the elderly, we analyzed 375 octogenarians (60.3% women; 83.0 years [mean]) enrolled in the International Database on home BP in relation to cardiovascular outcome. Over 5.5 years (median), 155 participants died, 76 from cardiovascular causes, whereas 104, 55, 36, and 51 experienced a cardiovascular, cardiac, coronary, or cerebrovascular event, respectively. In 202 untreated participants, home diastolic in the lowest fifth of the distribution (≤65.1 mm Hg) compared with the multivariable-adjusted average risk was associated with increased risk of cardiovascular mortality and morbidity (hazard ratios [HRs], ≥1.96; P≤0.022), whereas the HR for cardiovascular mortality in the top fifth (≥82.0 mm Hg) was 0.37 (P=0.034). Among 173 participants treated for hypertension, the HR for total mortality in the lowest fifth of systolic home BP (<126.9 mm Hg) was 2.09 (P=0.020). In further analyses of home BP as continuous variable (per 1-SD increment), higher diastolic BP predicted lower cardiovascular mortality and morbidity and cardiac and coronary risk (HR≤0.65; P≤0.039) in untreated participants. In those treated, cardiovascular morbidity was curvilinearly associated with systolic home BP with nadir at 148.6 mm Hg and with a 1.45 HR (P=0.046) for a 1-SD decrease below this threshold. In conclusion, in untreated octogenarians, systolic home BP ≥152.4 and diastolic BP ≤65.1 mm Hg entails increased cardiovascular risk, whereas diastolic home BP ≥82 mm Hg minimizes risk. In those treated, systolic home BP <126.9 mm Hg was associated with increased total mortality with lowest risk at 148.6 mm Hg.

This study investigated the relationship between seasonal variations in blood pressure (BP) and the corresponding changes in meteorological parameters and weather-induced patients' discomfort. Hypertensives on stable treatment were assessed in winter-1, summer and winter-2 with clinic (CBP), home (HBP) and 24-hour ambulatory BP (ABP). Discomfort indices derived from temperature, humidity and atmospheric pressure that reflected subjects' discomfort were evaluated. Symptomatic orthostatic hypotension was assessed with a questionnaire. Sixty subjects (mean age 65.1±8.8 [s.d.], 39 men) were analyzed. CBP, HBP and daytime ABP were lower in summer than in winter (P<0.01). Nighttime ABP was unchanged, which resulted in a 55% higher proportion of non-dippers (P<0.001). All the discomfort indices that reflected weather-induced subjects' discomfort were higher in summer (P<0.05) and systolic daytime ABP was <110 mm Hg in 15 subjects (25%). Seasonal changes in temperature and the discomfort indices were correlated with BP changes (P<0.05). Multivariate analyses revealed that winter BP levels, seasonal differences in temperature, female gender and the use of diuretics predicted the summer BP decline. In conclusion, all aspects of the BP profile, except nighttime ABP, are reduced in summer, resulting in an increased prevalence of non-dippers in summer with unknown consequences. Seasonal BP changes are influenced by changes in meteorological parameters, anthropometric and treatment characteristics. Trials are urgently needed to evaluate the clinical relevance of excessive BP decline in summer and management guidelines for practicing physicians should be developed.

Studies in adults have shown similar levels of home (HBP) and daytime ambulatory blood pressure (dABP), which are lower than clinic blood pressure (CBP) measurements. This study investigated the impact of age on these differences. A total of 642 untreated children, adolescents, and adults referred to a hypertension clinic were evaluated with CBP, HBP, and dABP measurements within 4 weeks (mean age 38.6 ± 19.4 years; range 5-78 years; 61.1% males). In children, dABP was higher than both CBP and HBP. These differences were progressively eliminated with increasing age, and after the age of 30 years, dABP was similar to HBP, and both were lower than CBP. In subjects aged ≥60 years, dABP appeared to be lower than HBP. Age and hypertension appeared to be the main independent predictors of the differences among the three methods.These data suggest that the relationship between office and out-of-office blood pressure measurements is not the same across all age groups and should be taken into account in the evaluation of subjects with elevated blood pressure in clinical practice.

The ambulatory arterial stiffness index (AASI) has been introduced as an index of arterial function, predicting cardiovascular events. However, treatment-induced changes in AASI are rather equivocal. This study aims to: (i) present the results of treatment-induced changes in AASI in untreated subjects with elevated blood pressure (BP), subjected to antihypertensive treatment for 1 year and (ii) perform a meta-analysis of studies reporting on treatment-induced change in AASI. A total of 104 subjects (mean age 51.4±10.3 years, 62% males, mean follow-up: 13.6±2.4 months) were analyzed. Despite significant reductions in 24-h ambulatory systolic/diastolic BP, pulse pressure and pulse wave velocity (mean change: -15.9±12/-10.4±7.6 mm Hg, -5.4±6.8 mm Hg, -0.7±1.9 m s(-1), respectively, all P<0.05), there was no significant change (Follow up-Baseline) in AASI values (mean change: 0.01±0.17, P=not significant). The treatment-induced change in AASI was correlated with baseline AASI (r=-0.61), baseline 24-h pulse pressure (-0.26), treatment-induced change in 24-h pulse pressure (0.26) and in systolic/diastolic nocturnal dipping (-0.25/-0.40, respectively). Meta-analysis of eight trials (n=990) revealed a marginal decrease in AASI with antihypertensive treatment (pooled change: -0.018 (95% confidence interval (CI): -0.033,-0.003)). When the analysis was restricted to data with renin-angiotensin system blockers (n=755, 76% of total), the results did not significantly change (pooled change -0.028 (95% CI -0.048, -0.007)). In conclusion, although AASI is an independent predictor of cardiovascular events, its response to antihypertensive treatment is only marginal and clinically uncertain, which may render its use as a therapeutic target in clinical practice questionable.

Hypertension significantly contributes to the increased cardiovascular morbidity and mortality, thus leading to rising healthcare costs. The objective of this study was to quantify the clinical and economic benefits of optimal systolic blood pressure (SBP), in a setting under severe financial constraints, as in the case of Greece. Hence, a Markov model projecting 10-year outcomes and costs was adopted, in order to compare two scenarios. The first one depicted the "current setting", where all hypertensives in Greece presented an average SBP of 164 mmHg, while the second scenario namely "optimal SBP control" represented a hypothesis in which the whole population of hypertensives would achieve optimal SBP (i.e. <140 mmHg). Cardiovascular events' occurrence was estimated for four sub-models (according to gender and smoking status). Costs were calculated from the Greek healthcare system's perspective (discounted at a 3% annual rate). Findings showed that compared to the "current setting", universal "optimal SBP control" could, within a 10-year period, reduce the occurrence of non-fatal events and deaths, by 80 and 61 cases/1000 male smokers; 59 and 37 cases/1000 men non-smokers; whereas the respective figures for women were 69 and 57 cases/1000 women smokers; and accordingly, 52 and 28 cases/1000 women non-smokers. Considering health expenditures, they could be reduced by approximately €83 million per year. Therefore, prevention of cardiovascular events through BP control could result in reduced morbidity, thereby in substantial cost savings. Based on clinical and economic outcomes, interventions that promote BP control should be a health policy priority.