Reproducibility of ambulatory blood pressure changes from the initial values on two different days

Abstract

OBJECTIVE:We tested the reproducibility of changes in the ambulatory blood pressure (BP) from the initial values, an indicator of BP reactivity and cardiovascular health outcomes, in young, healthy adults.METHOD:The subjects wore an ambulatory BP monitor attached by the same investigator at the same time of day until the next morning on two different days (day 1 and day 2) separated by a week. We compared the ambulatory BP change from the initial values at hourly intervals over 24 waking and sleeping hours on days 1 and 2 using linear regression and repeated measures analysis of covariance.RESULTS:The subjects comprised 88 men and 57 women (mean age±SE 22.4±0.3 years) with normal BP (118.3±0.9/69.7±0.6 mmHg). For the total sample, the correlation between the ambulatory BP change on day 1 vs. day 2 over 24, waking, and sleeping hours ranged from 0.37–0.61; among women, the correlation was 0.38–0.71, and among men, it was 0.24–0.52. Among women, the ambulatory systolic/diastolic BP change was greater by 3.1±1.0/2.4±0.8 mmHg over 24 hours and by 3.0±1.1/2.4±0.8 mmHg over waking hours on day 1 than on day 2. The diastolic ambulatory BP change during sleeping hours was greater by 2.2±0.9 mmHg on day 1 than on day 2, but the systolic ambulatory BP change during sleeping hours on days 1 and 2 did not differ. Among men, the ambulatory BP change on days 1 and 2 did not differ.CONCLUSION:Our primary findings were that the ambulatory BP change from the initial values was moderately reproducible; however, it was more reproducible in men than in women. These results suggest that women, but not men, may experience an alerting reaction to initially wearing the ambulatory BP monitor.

The antihypertensive effects of aerobic versus isometric handgrip resistance exercise

“…The BP increase during the first hour in the laboratory also seen in our previous work [21, 22] and others [31] reflects the typical morning circadian increase in BP [20–22, 24–26, 32]. The BP increase during subsequent hours under ambulatory compared to laboratory conditions has also been observed in our previous work [21, 25, 33, 34] and that of others [35–37]. Higher ambulatory than laboratory BP has been noted especially among male subjects with high BMI but without diagnosed hypertension [36, 38, 39] as characterized our sample (Table 1).…”

“…We omitted ambulatory BP readings of SBP >220 or <80 mmHg, or DBP >130 or <40 mmHg according to the manufacturer’s exclusion criteria. Ambulatory BP studies following the screening visits (Visits 1–3) were used to familiarize subjects with the technology [25], confirm their ability to follow all protocols, and lastly that they met the inclusion criteria of having prehypertension to stage 1 hypertension [26]. …”

Short-term reproducibility of ambulatory blood pressure measurements: a systematic review and meta-analysis of 35 observational studies

“…Several studies used Bland–Altman statistics to describe intra-individual reproducibility and had provided enough data for meta-analysis [ 9 , 11 , 14 , 21 – 27 , 28 ]. The detailed meta-analysis results can be found in Appendix 4, Supplemental Digital Content.…”

The Effect of Atorvastatin on Habitual Physical Activity among Healthy Adults

“…Therefore, we examined the seasons in which the subjects participated as a fixed factor in our statistical analyses and found season not to exert any statistically significant effects on the findings. Second, the subjects may have experienced an alerting reaction to wearing the accelerometer for the first time prior to randomization to drug treatment group which could account for the decreases in physical activity pre- to post-treatment that we observed (2,3). However, accelerometers have demonstrated test-retest reliability (11,20), and therefore, a decline in physical activity levels due to the alerting reaction of initially wearing the accelerometer was not likely to occur or explain our findings.…”