208 Number of measurements required for analysis of the diurnal blood pressure curve in normal subjects

Thijs, Lutgarde; Staessen, Jan A.; Fagard, Robert; Zachariah, Prince K.; Améry, A

doi:10.1097/00004872-199312050-00377

Cited by 26 publications

(39 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The sampling interval was randomized to take a reading on the average of every 1575 min for daytime hours (0600-2200 h) and on the average of every 3075 min for nighttime hours (2200-0600 h). 21 One repeat measurement was taken if the first measurement was unsuccessful during the daytime hours and two repeat measurements were taken during the nighttime hours. The inflation of the cuff for each measurement was programmed to inflate 30 mmHg greater than the previous reading.…”

Section: Twenty-four Hour Ambulatory Blood Pressure Monitoringmentioning

confidence: 99%

Time of day for exercise on blood pressure reduction in dipping and nondipping hypertension

2005

View full text Add to dashboard Cite

Time of day (TOD) for exercise may influence blood pressure (BP) reduction in hypertension because of the diurnal variation of BP and the duration of BP reduction following a single bout of exercise. The purpose of this study was to observe the effects of TOD for exercise on ambulatory blood pressure reduction in dipping (n ¼ 5) and nondipping (n ¼ 9) hypertension (o10% drop in nighttime BP (BP night )). Hypotheses: (1) evening exercise (PM ex ) would exhibit a greater BP night reduction in NonDippers than Dippers, (2) morning exercise (AM ex ) would exhibit similar daytime BP (BP day ) reduction in Dippers and Non-Dippers, (3) AM ex would exhibit greater 24 h BP (BP 24 h ) reduction than PM ex in Dippers, and (4) AM ex and PM ex would exhibit similar BP 24 h reduction in NonDippers. BP responses to AM ex (0600-0800 h; 30 min at 50% VO 2peak ) and PM ex (1700-1900 h) were compared to each control day in a randomized design. Systolic (S) and diastolic (D) BP were averaged for BP 24 h , BP day , and BP night . A two-way ANOVA (dipping X time of exercise) using BP reduction with repeated measures were performed at Po0.05. Findings: (1) Non-Dippers respond to exercise despite of TOD for exercise, (2) PM ex exhibited a greater SBP night reduction in Non-Dippers than Dippers, (3) AM ex exhibited similar SBP day reductions in Dippers and Non-Dippers, and (4) AM ex and PM ex exhibited similar SBP 24 h reduction in Dippers and NonDippers. Dippers and Non-Dippers respond differently to TOD for exercise. The duration of the BP reduction persists up to 24 h after exercise.

show abstract

Section: Twenty-four Hour Ambulatory Blood Pressure Monitoringmentioning

confidence: 99%

Time of day for exercise on blood pressure reduction in dipping and nondipping hypertension

2005

View full text Add to dashboard Cite

show abstract

“…First, we programmed our ABP readings at a constant interval during the day and night for 30 min. 2 However, from the current results as well as from those published before, 10,18 it is unlikely that a shorter interval between consecutive measurements in the full recordings, of for instance 15 min, would have had a bearing on the present conclusions. Second, middle-aged and older women made up the majority of the Ohasama cohort.…”

Section: Discussionmentioning

confidence: 44%

“…Previous studies clarified that the 24-h systolic and diastolic blood pressures are highly reproducible, even if the number of readings are reduced to one every 30 min 10 or to 1 per hour. 18 In Thijs et al 18 study, the relative RC for 24-h blood pressure in recordings with only 1-hourly readings compared with the full recordings was 9% systolic and 12% diastolic. For the night-to-day blood pressure difference, RCC was 23% systolic and 30% diastolic.…”

Section: Discussionmentioning

confidence: 97%

“…17 The relative RC was RC expressed as a percentage of the maximal variability of the parameter under study. 18 Maximal variability was four times the s.d. for the between-subjects variation in AASI or PP in the full recordings.…”

Section: Discussionmentioning

confidence: 99%

“…10 Di Rienzo et al 10 did not report on PP, but from the results on systolic and diastolic pressure one may infer that up to 30-min intervals estimates of 24-h PP would be within 2 mm Hg of those from continuous recordings, a result in-line with our current findings. Thijs et al 18 studied 97 normotensive volunteers, aged 23-84 years, who underwent ambulatory monitoring with readings programmed at 7.5-min intervals from 0800 to 2000 h and at 15-min intervals for the remainder of the day. If only the readings at 30-min or 1-h intervals were considered, estimates of PP were within 0.5 mm Hg of those derived from the full recordings.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

How many measurements are needed to provide reliable information in terms of the ambulatory arterial stiffness index? the Ohasama study

et al. 2010

Self Cite

View full text Add to dashboard Cite

The aim of this study was to investigate how frequent ambulatory blood pressure (ABP) readings need to be obtained to reproduce the ambulatory arterial stiffness index (AASI) and pulse pressure (PP) without loss of information. We compared concordance from full and reduced ABP recordings. We recorded 24-h ABP at 30-min intervals in 1542 residents of Ohasama, Japan (baseline age, 40-93 years; 63.4% women). We randomly excluded up to 16 readings per recording or we selected readings at fixed 1-or 2-h intervals. Using full recordings as reference, we computed for the reduced recordings repeatability coefficient by Bland and Altman's approach. By Cox regression, we also calculated multivariate-adjusted hazard ratios for cardiovascular mortality. The median number of ABP readings per recording was 46. Randomly excluding more readings reduced the concordance of AASI, but not PP. Selecting blood pressure readings at 1-or 2-h intervals produced mean values of AASI and PP, which significantly differed from those in full recordings. During follow-up (median, 13.3 years) 126 cardiovascular deaths occurred. Across quartiles, AASI significantly predicted cardiovascular mortality in a U-shaped manner. AASI lost its prognostic significance when the number of randomly excluded readings increased from 8 to 16 or when the interval between readings was 1 h or longer. Compared with PP, AASI is less reproducible when the number of readings in ABP decreases, but this does not affect the predictive accuracy of AASI for cardiovascular mortality, until the median number of readings per ABP recording is less than B35.

show abstract

Blood pressure variability in relation to outcome in the International Database of Ambulatory blood pressure in relation to Cardiovascular Outcome

et al. 2010

Self Cite

View full text Add to dashboard Cite

Ambulatory blood pressure (BP) monitoring provides information not only on the BP level but also on the diurnal changes in BP.In the present review, we summarized the main findings of the International Database on Ambulatory BP in relation to Cardiovascular Outcome (IDACO) with regard to risk stratification based on BP variability. The predictive accuracy of daytime and nighttime BP and the night-to-day BP ratio depended on the disease outcome under study and treatment status, and differed for fatal outcomes compared with the composite of fatal and nonfatal diseases. An exaggerated morning surge, exceeding the 90th percentile of the population, is an independent risk factor for mortality and cardiovascular and cardiac events. Conversely, a sleep-trough or preawakening morning surge in systolic BP below 20 mm Hg is probably not associated with an increased risk of death or cardiovascular events. BP variability as captured by the average of the daytime and nighttime s.d. weighted for the duration of the daytime and nighttime interval (s.d. dn ) and the average real variability (ARV 24 ) predicted the outcome, but improved the prediction of the composite of all cardiovascular events by only 0.1%. In conclusion, the IDACO observations support the concept that BP variability adds to risk stratification, but above all highlight that 24-h ambulatory BP level remains the main predictor to be considered in clinical practice. Hypertension Research (2010) 33, 757-766; doi:10.1038/hr.2010.110; published online 8 July 2010Keywords: blood pressure; cardiovascular outcome; diurnal blood pressure variability; morning surge INTRODUCTION Ambulatory monitoring allows the registration of blood pressure (BP) throughout the day in patients engaged in their usual activities. Ambulatory BP recordings have high reproducibility, are not subject to digit preference, and avoid the transient rise of a patient's BP in response to a medical environment, the so-called white-coat effect. 1,2 Collaborative meta-analyses of individual patient data constitute a powerful research tool to clarify the role of cardiovascular risk factors in relation to total and cause-specific mortality and morbidity, over and beyond the prognostic information generated by single-cohort studies. 3,4 The international database on ambulatory BP monitoring 5 illustrated to what extent a meta-analysis of individual patient data can contribute to our understanding of the distribution 5,6 and the diurnal profile 5,7 of ambulatory BP across ethnically diverse populations. This database, constructed in 1993This database, constructed in -1994 however, lacked a

show abstract

208 Number of measurements required for analysis of the diurnal blood pressure curve in normal subjects

Cited by 26 publications

References 0 publications

Time of day for exercise on blood pressure reduction in dipping and nondipping hypertension

Time of day for exercise on blood pressure reduction in dipping and nondipping hypertension

How many measurements are needed to provide reliable information in terms of the ambulatory arterial stiffness index? the Ohasama study

Blood pressure variability in relation to outcome in the International Database of Ambulatory blood pressure in relation to Cardiovascular Outcome

Contact Info

Product

Resources

About