Within-visit blood pressure variability: relevant factors in the general population

Abstract

The objective of this study was to use a nationwide epidemiological survey to investigate the factors that affect within-visit blood pressure (BP) variability. We analyzed the Korean National Health and Nutrition Examination Survey (KNHNES) data for 2005 (n=5488). We examined three within-visit BP variability parameters that include the following: the alarm reaction (AR), defined as the first BP reading minus the third BP reading; the BP discrepancy, defined as the maximal BP reading minus the minimal BP reading (ΔBPmax); and the s.d. (BPSD). Age, fasting glucose, eGFR, total cholesterol, LDL cholesterol, and the metabolic syndrome (MetS) score were the relevant factors that affected the systolic AR, ΔSBPmax and SBPSD. Multiple linear regression models revealed that age (P<0.0001), the office systolic BP (SBP) level (P<0.0001), the MetS score (P<0.0001), the female gender (P=0.007) and the eGFR (P=0.049) were independently associated with the systolic AR, whereas age (P<0.0001), the office SBP level (P<0.0001), and the female gender (P=0.024 and 0.022) were independently associated with ΔSBPmax and SBPSD, respectively. Within-visit BP variability, especially the variability associated with the SBP, was significantly associated with increased age, female gender and cardiovascular risk factors, such as hypertension, low eGFR and adverse glucose and lipid profiles. In addition, increased age, female gender, the eGFR and the MetS score were independently relevant factors that affected the systolic AR. Systolic within-visit BP variability and systolic AR are associated with cardiovascular risk factors.

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

“…In contrast, studies that included subjects with hypertension found higher standard deviation of the difference values ranging from 4–13 mmHg, independent of whether ambulatory BP measurements were separated by several weeks (4,5,7,9,12) or by several months (6,10,13). The greater BP variability among individuals with a higher BP is consistent with recent findings that visit-to-visit (23,24) and within-visit (25) BP variability for resting BP correlates positively with BP status.…”

“…Furthermore, laboratory experiments indicate that sympathetic nerve activity is positively associated with BP in men; however, if an association is found among women, it is in the opposite direction to that of men (28,29). In addition, it would seem the men in our study would be more susceptible to experiencing greater BP variability between ambulatory BP measurements made on different days due to having higher resting BP than the women (23–25). Collectively, these data suggest that the men in our study would have been more likely to experience an alerting reaction to initially wearing the ambulatory BP monitor, whereas we observed the opposite.…”

“…Shin et al (25) found that women exhibited greater within-visit auscultatory BP variability than men, including greater differences between the initial and subsequent BP measurements; this effect was considered to result from an alerting reaction to the initial auscultatory BP measurement. Calvo et al (15) found that when women and men with hypertension wore an ambulatory BP monitor continuously for 48 hours, the average ambulatory BP over 24 hours and the waking hours was lower on the second day than on the first day.…”

Use of the plasma triglyceride/high-density lipoprotein cholesterol ratio to identify cardiovascular disease in hypertensive subjects

“…We defined hypertension if the average of three readings was equal or above 140/90 mm Hg within a visit. Although guidelines recommend two visits to define office hypertension, the data regarding hypertension prevalence, knowledge, and control in the National Health and Nutrition Examination Survey population studies were based on one visit BP measurement 21 and recent publications based on National Health and Nutrition Examination Survey 22,23 and Korean National Health and Nutrition Examination Survey samples 24 were based on three measurement records within a visit. Thus, albeit imperfect, our approach was as rigorous as that used in several wellrespected studies.…”

Regional Fat Distribution and Blood Pressure Level and Variability

“…These measures have been used to describe BP variability in previous studies. 11-19, 27-30 ARV is calculated as (ΔBP1+ΔBP2+ΔBP3+ΔBP4)/4 for short-term ARV and as (ΔBP1+ΔBP2)/2 for long-term ARV where ΔBP is the absolute difference between successive BP measurements. In contrast with SD, ARV takes the order of the BP measurements into account.…”