HOme Blood Pressure In Relation Research Articles

PROGNOSTIC SIGNIFICANCE OF BLOOD PRESSURE FLUCTUATIONS IN THE MORNING AND EVENING FOR CARDIOVASCULAR OUTCOMES

Objective: Independent of office blood pressure (BP) levels, home BP is associated with the occurrence of cardiovascular events. Abnormal diurnal variations in BP have been linked to cardiovascular disease (CVD). However, data on diurnal patterns of home BP, the morning and evening BP difference (MEdiff), are scarce. This study looked into the relationship between all MEdiff indices and cardiovascular outcomes. Design and method: The association was assessed using data from the International Database of Home Blood Pressure in Relation to Cardiovascular Outcome (IDHOCO), which comprised 6753 patients from five cohorts. We found 1254 patients who had taken home BP readings every morning and every evening for more than 14 days. The MEdiff over a 13-day period, omitting the first day, for each patient were used to calculate the average (MEdiff_sbp_avg), minimum (MEdiff sbp_min), and maximum (MEdiff_sbp_max) values. MEdiff is defined as morning (6AM-8AM) minus evening BP (8PM-10PM) measures. The prognostic values of these parameters were assessed using Cox proportional hazards models. Factors adjusted in the base model included age, sex, body mass index, total cholesterol, high-density lipoprotein cholesterol, smoking status, prevalence of diabetes, history of cardiovascular disease, and antihypertensive drug treatment. Results: Only MEdiff_min_sbp strongly predicted CVD (183 events; mean follow-up time of 13.4 years), but MEdiff_avg_sbp (hazard ratio: 0.906, 95% CI: 0.087-1.018 per SD), MEdiff_max_sbp (0.949, 0.846-1.064 per SD) did not. Spline regression analysis with thresholds of -17 mmHg and -4 mmHg revealed a U-curve association between MEdiff_min_sbp and the risk of CVD outcomes. Three groups were identified by MEdiff_min_sbp: lower than -17 mmHg (Low, n = 574), between -17 and -4 mmHg (medium, n = 568) and higher than -4 mmHg (high, n = 112). Compared to the low group, the high group had a significantly higher risk of CVD (1.353, 1.052-1.739), in the models with adjustment for the mean of the morning and evening SBP values, and MEdiff_avg_sbp or various BP variability indices. Conclusions: MEdiff_min_sbp was strongly associated with an increased risk of cardiovascular outcomes, suggesting that it could be a useful BP index for describing abnormal BP diurnal variations for CVD risk prediction.

Cardiovascular outcome and home blood pressure in relation to silent myocardial ischemia in a clinical population: The J-HOP study.

Several guidelines recommend measuring home blood pressure (BP) and lowering blood pressure than ever before. But several studies reported that lowering diastolic blood pressure (DBP) increased the incidence of coronary artery disease (CAD). We analyzed 3605 individuals who underwent both home and office BP monitoring over 14days and baseline Hs-cTnT measurement and identified follow-up data of the Japan Morning Surge-Home Blood Pressure (J-HOP) study who had a history of or risk factors for cardiovascular disease. During a mean follow-up period of 6.4years (23173 person-years), 114 coronary artery disease and 81 stroke events occurred. Elevated Hs-cTnT (≥0.014ng/mL) was observed in 298 patients (8.3%). In the group with non-elevated Hs-cTnT (<0.014ng/mL, n=3307), an adjusted Cox hazard model showed that home systolic BP (SBP) was associated with a risk of stroke incidence (hazard ratio [HR] per 1 SD, 1.62; 95% confidence interval [CI], 1.29-2.03). This association was also observed in office SBP (HR per 1 SD, 1.43; 95%CI, 1.07-1.91). There was no association between office or home BP and CAD events in the group with non-elevated Hs-cTnT. In the group with elevated Hs-cTnT, an adjusted Cox hazard model showed that home DBP was associated with a risk of CAD incidence (HR per 1 SD, 0.54; 95%CI, 0.30-0.99). However, this association was not observed in office DBP. In patients with elevated Hs-cTnT, which is a marker of subclinical myocardial ischemia, excessive lowering of home DBP may be associated with a risk of incident CAD.

Relationship between office and home blood pressure with increasing age: The International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO).

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.

Defining thresholds for home blood pressure monitoring in octogenarians.

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.

Prognosis of White-Coat and Masked Hypertension

Home blood pressure monitoring is useful in detecting white-coat and masked hypertension and is recommended for patients with suspected or treated hypertension. The prognostic significance of white-coat and masked hypertension detected by home measurement was investigated in 6458 participants from 5 populations enrolled in the International Database of HOme blood pressure in relation to Cardiovascular Outcomes. During a median follow-up of 8.3 years, 714 fatal plus nonfatal cardiovascular events occurred. Among untreated subjects (n=5007), cardiovascular risk was higher in those with white-coat hypertension (adjusted hazard ratio 1.42; 95% CI [1.06–1.91]; P =0.02), masked hypertension (1.55; 95% CI [1.12–2.14]; P &lt;0.01) and sustained hypertension (2.13; 95% CI [1.66–2.73]; P &lt;0.0001) compared with normotensive subjects. Among treated patients (n=1451), the cardiovascular risk did not differ between those with high office and low home blood pressure (white-coat) and treated controlled subjects (low office and home blood pressure; 1.16; 95% CI [0.79–1.72]; P =0.45). However, treated subjects with masked hypertension (low office and high home blood pressure; 1.76; 95% CI [1.23–2.53]; P =0.002) and uncontrolled hypertension (high office and home blood pressure; 1.40; 95% CI [1.02–1.94]; P =0.04) had higher cardiovascular risk than treated controlled patients. In conclusion, white-coat hypertension assessed by home measurements is a cardiovascular risk factor in untreated but not in treated subjects probably because the latter receive effective treatment on the basis of their elevated office blood pressure. In contrast, masked uncontrolled hypertension is associated with increased cardiovascular risk in both untreated and treated patients, who are probably undertreated because of their low office blood pressure.

Reference frame for home pulse pressure based on cardiovascular risk in 6470 subjects from 5 populations

The absence of an outcome-driven reference frame for self-measured pulse pressure (PP) limits its clinical applicability. In an attempt to derive an operational threshold for self-measured PP, we analyzed 6470 participants (mean age 59.3 years; 56.9% women; 22.5% on antihypertensive treatment) from 5 general population cohorts included in the International Database on HOme blood pressure in relation to Cardiovascular Outcome. During 8.3 years of follow-up (median), 294 cardiovascular deaths, 393 strokes and 336 cardiac events occurred. In 3285 younger subjects (<60 years), home PP only predicted all-cause and cardiovascular mortality (P⩽0.036), whereas in 3185 older subjects (⩾60 years) PP predicted total and cardiovascular mortality (P⩽0.0067) and all cardiovascular and coronary events (P⩽0.044). However, PP did not substantially refine risk prediction based on classical risk factors including mean blood pressure (generalized R(2) statistic ⩽0.20%). In older subjects, the adjusted hazard ratios expressing the risk in the upper decile of home PP (⩾76 mm Hg) versus the average risk in whole population were 1.41 (95% confidence interval, 1.09-1.81; P=0.0081) for all-cause mortality, 1.62 (1.11-2.35; P=0.012) for cardiovascular mortality and 1.31 (1.00-1.70; P=0.047) for all fatal and nonfatal cardiovascular end points combined. The low number of events precluded an analysis by tenths of the PP distribution in younger participants. In conclusion, a home PP of ⩾76 mm Hg predicted cardiovascular outcomes in the elderly with the exception of stroke, whereas in younger subjects no threshold could be established.

Is white-coat hypertension a harbinger of increased risk?

White-coat hypertension is defined by elevated office and normal out-of-office blood pressure (home or ambulatory) in untreated subjects. This condition is common in clinical practice and requires appropriate work-up for detection and management. Many studies have examined the relationship between white-coat hypertension and cardiovascular risk but with marked heterogeneity in the definitions and methodology applied. Thus, the results have been inconsistent leading to confusion in scientific research and clinical practice. Some but not all the relevant studies suggested that white-coat hypertension is associated with subclinical target-organ damage, yet the cross-sectional design of these studies and the fact that these indices are only surrogate end points do not allow firm conclusions to be drawn. In recent years, longitudinal studies have examined the prognostic significance of white-coat hypertension in terms of cardiovascular morbidity and mortality. Most of them indicate that white-coat hypertensive compared with normotensive subjects present a moderate-in most cases not significant-increase in risk. Meta-analyses of raw data from large databases, such as the International Database on Ambulatory blood pressure and Cardiovascular Outcomes (IDACO) and the International Database on HOme blood pressure in relation to Cardiovascular Outcomes (IDHOCO) allowed separate powered analyses in untreated subjects and provided a clearer picture regarding the modest risk associated with white-coat hypertension, especially in the long term. White-coat hypertension is regarded as an intermediate phenotype between normotension and hypertension associated with increased risk of developing sustained hypertension, and therefore requires regular follow-up using nonpharmacological measures.

The International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO): moving from baseline characteristics to research perspectives.

The objective of this study is to construct an International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO). The main goal of this database is to determine outcome-based diagnostic thresholds for the self-measured home blood pressure (BP). Secondary objectives include investigating the predictive value of white-coat and masked hypertension, morning and evening BP, BP and heart rate variability, and the home arterial stiffness index. We also aim to determine an optimal schedule for home BP measurements that provides the most accurate risk stratification. Eligible studies are population-based, have fatal as well as nonfatal outcomes available for analysis, comply with ethical standards, and have been previously published in peer-reviewed journals. In a meta-analysis based on individual subject data, composite and cause-specific cardiovascular events will be related to various indexes derived by home BP measurement. The analyses will be stratified by a cohort and adjusted for the clinic BP and established cardiovascular risk factors. The database includes 6753 subjects from five cohorts recruited in Ohasama, Japan (n=2777); Finland (n=2075); Tsurugaya, Japan (n=836); Didima, Greece (n=665); and Montevideo, Uruguay (n=400). In these five cohorts, during a total of 62 106 person-years of follow-up (mean 9.2 years), 852 subjects died and 740 participants experienced a fatal or nonfatal cardiovascular event. IDHOCO provides a unique opportunity to investigate several hypotheses that could not reliably be studied in individual studies. The results of these analyses should be of help to clinicians involved in the management of patients with suspected or established hypertension.