Influence of Sex on the Accuracy of Oscillometric-Derived Blood Pressures

Comparisons of an automated oscillometric device with a hybrid manual auscultatory device for the Korea National Health and Nutrition Examination Survey

This study evaluated an oscillometric device (OD), Microlife WatchBP Office AFIB, and a hybrid manual auscultatory device (AD), Greenlight 300TM, to determine a suitable blood pressure (BP) measurement device for the Korea National Health and Nutrition Examination Survey in a mercury-free context. Adhering to the 2018 Universal Standard's suggested consensus, the study involved 800 subjects (mean age 51.2 ± 17.5 years; 44.3% male), who underwent triplicate BP measurements following 5 min of rest in a randomized order (OD-first: 398 participants; AD-first: 402 participants). BP difference was calculated as OD value minus AD value, with results stratified by measurement sequence. The overall BP difference and tolerable error probability were -1.1 ± 6.5/-2.6 ± 4.9 mmHg and 89.2%/92.5% for systolic/diastolic BP (SBP/DBP), respectively. Lin's concordance correlation coefficient was 0.907/0.844 for SBP/DBP (OD-first/AD-first: 0.925/0.892 for SBP, 0.842/0.845 for DBP). The overall agreement for hypertension (BP ≥ 140 and/or 90 mmHg) was 0.71 (p < 0.0001), and the OD underestimated the overall hypertension prevalence by 5.1%. Analysis of the AD-first data revealed a lower level of agreement compared to the OD-first data; however, the observed blood pressure difference adhered to Criterion 1 of the 2018 Universal Standard. Microlife met the Criterion 1 of 2018 Universal Standard but underestimated the prevalence of hypertension. The BP discrepancy increased with higher BP levels, male sex, and smaller AC. With increasing age, the discrepancy decreased for SBP and increased for DBP.

Sex Differences in Blood Pressure and Potential Implications for Cardiovascular Risk Management

BACKGROUND

Accurate blood pressure (BP) measurement is critical for optimal cardiovascular risk management. Age-related trajectories for cuff-measured BP accelerate faster in women compared with men, but whether cuff BP represents the intraarterial (invasive) aortic BP is unknown. This study aimed to determine the sex differences between cuff BP, invasive aortic BP, and the difference between the 2 measurements.

METHODS

Upper-arm cuff BP and invasive aortic BP were measured during coronary angiography in 1615 subjects from the Invasive Blood Pressure Consortium Database. This analysis comprised 22 different cuff BP devices from 28 studies.

RESULTS

Subjects were 64±11 years (range 40-89) and 32% women. For the same cuff systolic BP (SBP), invasive aortic SBP was 4.4 mm Hg higher in women compared with men. Cuff and invasive aortic SBP were higher in women compared with men, but the sex difference was more pronounced from invasive aortic SBP, was the lowest in younger ages, and the highest in older ages. Cuff diastolic blood pressure overestimated invasive diastolic blood pressure in both sexes. For cuff and invasive diastolic blood pressure separately, there were sex*age interactions in which diastolic blood pressure was higher in younger men and lower in older men, compared with women. Cuff pulse pressure underestimated invasive aortic pulse pressure in excess of 10 mm Hg for both sexes in older age.

CONCLUSIONS

For the same cuff SBP, invasive aortic SBP was higher in women compared with men. How this translates to cardiovascular risk prediction needs to be determined, but women may be at higher BP-related risk than estimated by cuff measurements.

Identifying Isolated Systolic Hypertension From Upper-Arm Cuff Blood Pressure Compared With Invasive Measurements

Isolated systolic hypertension (ISH) is the most common form of hypertension and is highly prevalent in older people. We recently showed differences between upper-arm cuff and invasive blood pressure (BP) become greater with increasing age, which could influence correct identification of ISH. This study sought to determine the difference between identification of ISH by cuff BP compared with invasive BP. Cuff BP and invasive aortic BP were measured in 1695 subjects (median 64 years, interquartile range [55-72], 68% male) from the INSPECT (Invasive Blood Pressure Consortium) database. Data were recorded during coronary angiography among 29 studies, using 21 different cuff BP devices. ISH was defined as ≥130/<80 mm Hg using cuff BP compared with invasive aortic BP as the reference. The prevalence of ISH was 24% (n=407) according to cuff BP but 38% (n=642) according to invasive aortic BP. There was fair agreement (Cohen κ, 0.36) and 72% concordance between cuff and invasive aortic BP for identifying ISH. Among the 28% of subjects (n=471) with misclassification of ISH status by cuff BP, 20% (n=96) of the difference was due to lower cuff systolic BP compared with invasive aortic systolic BP (mean, -16.4 mm Hg [95% CI, -18.7 to -14.1]), whereas 49% (n=231) was from higher cuff diastolic BP compared with invasive aortic diastolic BP (+14.2 mm Hg [95% CI, 11.5-16.9]). In conclusion, compared with invasive BP, cuff BP fails to identify ISH in a sizeable portion of older people and demonstrates the need to improve cuff BP measurements.

Moderate morning rise in blood pressure has lowest risk of stroke but only in women

BACKGROUND

The morning period which is recognized as the highest risk for cardiovascular events is associated with a surge in blood pressure (BP). However, it is unclear what aspect of this rise is important.

AIM

To determine whether the rate of rise (RoR), the magnitude (day night difference) or the product [BP power (BPPower)] is associated with increased cardiovascular risk.

METHODS

We developed a logistic equation method to fit individual 24-h patterns of BP to determine RoR, amplitude and BPPower using the ambulatory recordings from the Ohasama study including 564 men and 971 women (16.6 years follow-up).

RESULTS

Men had a higher risk of cardiovascular events than women (24, 16%, P < 0.001). Age and night BP were strong linear risk predictors. In men sorting risk by quintiles of BPPower (adjusted for age, night BP, smoking status) revealed no clear linear or nonlinear pattern. However, in women BPPower had a U-shaped relationship with the lowest risk being the 2-3rd quintile for all cardiovascular events (Pquadratic = 0.01) including cardiovascular death (Pquadratic = 0.03) and nonfatal stroke (Pquadratic = 0.02). A similar but less clear trend was observed with the RoR but only stroke (infarct) reached significance (Pquadratic = 0.03) while sorting by range showed a U shaped pattern for combined cardiovascular events (Pquadratic = 0.04).

CONCLUSION

These findings suggest that the morning BPPower is an important independent risk factor for predicting cardiovascular events and stroke but only in women with median levels having the lowest risk.

Relation of pulse and systolic and mean blood pressure to severe renal artery stenosis in patients undergoing concurrent coronary and renal angiography

Abrupt onset of renal ischemia is associated with increased blood pressure (BP), but it is unknown whether BP remains elevated in patients with chronic severe atherosclerotic renal artery stenosis (RAS). Patients undergoing coronary angiography who had concurrent renal angiography were divided into 3 groups: severe (stenosis ≥70% diameter reduction), moderate (10%-69%), and minimal RAS. Aortic BP was measured at the time of angiography. Renal angiography was performed in 762 (5.4%) of 14,181 patients undergoing coronary angiography. The mean age was 62 ± 12 years, 52% were women, 93% had hypertension, and 42% had diabetes mellitus. Minimal, moderate, or severe RAS was found in 62%, 30%, and 9% of patients. Patients with minimal RAS were younger, less likely to have hypercholesterolemia or coronary artery disease, and had a lower creatinine than patients with severe RAS. Severe RAS was associated with a lower diastolic BP and mean BP and a higher pulse pressure (PP), but there was no difference in systolic BP or the number of antihypertensive medications between the 3 groups. The degree of RAS had a weak positive correlation with PP, a weak negative correlation with diastolic BP, and almost no correlation with systolic BP or mean BP. In multivariate linear regression analysis, there was an association between severity of RAS and PP but not with mean BP or systolic BP. In conclusion, PP, but not systolic BP, diastolic BP, mean BP, or number of antihypertensive medications, was elevated in patients with severe RAS.