Measurement of Blood Pressure In and Out of the Office

Postprandial Responses to a Standardised Meal in Hypertension: The Mediatory Role of Visceral Fat Mass

Postprandial insulinaemia, triglyceridaemia and measures of inflammation are thought to be more closely associated with cardiovascular risk than fasting measures. Although hypertension is associated with altered fasting metabolism, it is unknown as to what extent postprandial lipaemic and inflammatory metabolic responses differ between hypertensive and normotensive individuals. Linear models adjusting for age, sex, body mass index (BMI), visceral fat mass (VFM) and multiple testing (false discovery rate), were used to investigate whether hypertensive cases and normotensive controls had different fasting and postprandial (in response to two standardised test meal challenges) lipaemic, glycaemic, insulinaemic, and inflammatory (glycoprotein acetylation (GlycA)) responses in 989 participants from the ZOE PREDICT-1 nutritional intervention study. Compared to normotensive controls, hypertensive individuals had significantly higher fasting and postprandial insulin, triglycerides, and markers of inflammation after adjusting for age, sex, and BMI (effect size: Beta (Standard Error) ranging from 0.17 (0.08), p = 0.04 for peak insulin to 0.29 (0.08), p = 4.4 × 10^-4 for peak GlycA). No difference was seen for postprandial glucose. When further adjusting for VFM effects were attenuated. Causal mediation analysis suggests that 36% of the variance in postprandial insulin response and 33.8% of variance in postprandial triglyceride response were mediated by VFM. Hypertensive individuals have different postprandial insulinaemic and lipaemic responses compared to normotensive controls and this is partially mediated by visceral fat mass. Consequently, reducing VFM should be a key focus of health interventions in hypertension. Trial registration: The ClinicalTrials.gov registration identifier is NCT03479866.

A Comparison of the Diagnostic Accuracy of Common Office Blood Pressure Measurement Protocols

BACKGROUND

The optimal approach to measuring office blood pressure (BP) is uncertain. We aimed to compare BP measurement protocols that differed based on numbers of readings within and between visits and by assessment method.

METHODS

We enrolled a sample of 707 employees without known hypertension or cardiovascular disease, and obtained 6 standardized BP readings during each of 3 office visits at least 1 week apart, using mercury sphygmomanometer and BpTRU oscillometric devices (18 readings per participant) for a total of 12,645 readings. We used confirmatory factor analysis to develop a model estimating "true" office BP that could be used to compare the probability of correctly classifying participants' office BP status using differing numbers and types of office BP readings.

RESULTS

Averaging 2 systolic BP readings across 2 visits correctly classified participants as having BP below or above the 140 mm Hg threshold at least 95% of the time if the averaged reading was <134 or >149 mm Hg, respectively. Our model demonstrated that more confidence was gained by increasing the number of visits with readings than by increasing the number of readings within a visit. No clinically significant confidence was gained by dropping the first reading vs. averaging all readings, nor by measuring with a manual mercury device vs. with an automated oscillometric device.

CONCLUSIONS

Averaging 2 BP readings across 2 office visits appeared to best balance increased confidence in office BP status with efficiency of BP measurement, though the preferred measurement strategy may vary with the clinical context.

High sodium intake is associated with masked hypertension in Japanese patients with type 2 diabetes and treated hypertension

BACKGROUND

Knowledge regarding the association between dietary sodium intake and the incidence of masked hypertension is limited.

METHODS

A total of 193 Japanese type 2 diabetic outpatients who had been treated with antihypertensive agents and with office blood pressures <140/90 mm Hg were recruited. Masked hypertension was defined as having office blood pressure <140/90 mm Hg and 24-h mean ambulatory blood pressure ≥130/80 mm Hg. The dietary sodium intake was estimated by measuring the 24-h urinary sodium excretion.

RESULTS

Masked hypertension was found in 128 (66.3%) patients. An age- and sex-adjusted univariate logistic regression analysis showed that urinary albumin excretion, renin-angiotensin system inhibitor use, office systolic blood pressure, and amount of dietary sodium intake were significantly associated with masked hypertension. A multivariate logistic regression analysis also identified an older age, renin-angiotensin system inhibitor use, an office elevated systolic blood pressure, and high dietary sodium intake to be independently associated with masked hypertension. When compared with those who consumed a low salt diet (sodium <120 mEq/day), the odds ratio for the risk of exhibiting masked hypertension in patients who consumed a medium salt diet (sodium 120 to <200 mEq/day) or a high salt diet (sodium ≥200 mEq/day) were 5.3 (P < 0.001) and 12.6 (P < 0.001), respectively.

CONCLUSIONS

Masked hypertension is a common feature in type 2 diabetic patients being treated for hypertension. The observed association with sodium intake raised the hypothesis that excessive sodium intake may play a part in the genesis of masked hypertension in these patients.

[Home blood pressure monitoring and control in a group of hypertensive patients]

This qualitative study was performed with 71 hypertensive patients, with the objectives to compare outpatient and home blood pressure monitoring (HBPM), to assess blood pressure control, and characterize white-coat hypertension. A nurse performed the outpatient blood pressure measurement. The home blood pressure monitoring was carried out over seven days. White-coat hypertension was quantified as a difference between the outpatient measurement and home blood pressure monitoring in the ranges from 1 to 5, 6 to 10 and > 10 mmHg. The outpatient blood pressure measurement was significantly higher (p<0.05) than the home blood pressure measurement. Pressure control corresponded to 9.9% in the outpatient measurement and 23.9% in the home blood pressure measurement. The white-coat effect > 10 mmHg was 57.7% for systolic and 32.4% for diastolic pressure, in the range from 6 to 10 mmHg. Home blood pressure measurement provided a better assessment of hypertensive patients' control.

Reliability of palpation of the radial artery compared with auscultation of the brachial artery in measuring SBP

BACKGROUND

Systolic blood pressure contributes more to cardiovascular disease than DBP, especially in elderly persons. Palpation of the radial artery to assess SBP - Riva-Rocci's technique - may be an attractive alternative for auscultatory SBP in these patients. Therefore, we investigated the difference between SBP determined by palpation of the radial artery (pSBP) and SBP assessed by auscultation of the brachial artery (aSBP).

METHODS

Patients were included from the waiting room of a hypertension outpatient clinic. In each patient eight simultaneous pSBP and aSBP measurements were assessed by two observers in the same arm. After every two readings the observers switched between pSBP and aSBP.

RESULTS

Forty patients were included, 25 men (62.5%), mean age 55.3 years (range 24-78). From a total of 320 measurements, mean difference between pSBP and aSBP was -5.2 mmHg (range -12-26 mmHg) (P < 0.01). This difference correlated significantly with BMI (r = 0.51, P < 0.01), but not with age (r = 0.15, P = 0.35), pulse rate (r = 0.29, P = 0.09) or mean SBP (r = 0.03, P = 0.85). After averaging the first three comparisons, reproducibility did not improve when increasing the number of comparisons. When correcting for the underestimation of 6 mmHg over the first three comparisons, Riva-Rocci's technique estimates SBP with an acceptable accuracy.

CONCLUSION

In clinical practice, Riva-Rocci's palpatory technique offers an acceptable alternative for auscultatory SBP measurement. It is recommended to take three measurements and then correct for the average underestimation of 6 mmHg.

Ambulatory blood pressure monitoring predicts cardiovascular events in treated hypertensive patients--an Anglo-Scandinavian cardiac outcomes trial substudy

BACKGROUND

Results of the Anglo-Scandinavian cardiac outcomes trial-blood pressure lowering arm (ASCOT-BPLA) showed significantly lower rates of coronary and stroke events in individuals allocated an amlodipine-perindopril combination drug regimen than in those allocated an atenolol-thiazide combination drug regimen. The aims of the ambulatory blood pressure (ABP) substudy of ASCOT were to examine the impact of the two blood pressure (BP)- lowering regimens on ambulatory pressures, test to what extent the between-treatment differences in cardiovascular outcome could be attributed to differences in ABP and assess whether ABP provides predictive information additional to that of clinic blood pressure (CBP) in treated hypertensive patients.

METHODS AND RESULTS

One thousand, nine hundred and five patients from four ASCOT centres had repeated ABPs performed over a median follow-up period of 5.5 years. As in the whole ASCOT population, CBP values were lower in amlodipine-perindopril-treated patients compared with those treated with atenolol-thiazide [between-regimen difference [95% confidence intervals (CIs)]]: [-1.5 (-2.4 to -0.5)/-1.2 (-1.8 to +0.5) mmHg]. Daytime BP during follow-up was higher in patients treated with amlodipine-perindopril therapy [+1.1 (0.1-2.1)/+1.6 (0.8-2.3) mmHg]; night-time systolic, but not diastolic BP, was lower in patients treated with amlodipine-perindopril therapy [-2.2 (-3.4 to +0.9)/+0.8 (0.0-1.6) mmHg]. The relative risk of a cardiovascular event associated with a 1 SD increment in accumulated mean BP was 1.35 (1.18-1.53) for clinic systolic BP, 1.30 (1.14-1.49) for daytime systolic BP and 1.42 (1.24-1.62) for night-time systolic BP. With adjustment for baseline variables, treatment regimen and clinic systolic BP, the hazard ratios were 1.17 (1.00-1.36) and 1.25 (1.08-1.47) for daytime and night-time systolic BP, respectively. The between-regimen adjusted hazard ratio for cardiovascular events (amlodipine-perindopril therapy versus atenolol-thiazide therapy) was 0.74 (0.55-1.01) and increased to 0.81 (0.60-1.10) after further adjustment for clinic systolic BP. Further, adjustment for night-time systolic BP increased the hazard ratio to 0.85 (0.62-1.16).

CONCLUSION

The amlodipine-perindopril and atenolol-thiazide regimens had different effects on daytime and night-time ABP, which may have contributed to the lower rates of events in patients treated with amlodipine-perindopril therapy. Both CBP and ABP were significantly associated with rates of cardiovascular events. ABP nocturnal pressures provided complimentary and incremental utility over CBP in the prediction of cardiovascular risk in treated hypertensive patients. These data support the use of ABP to assess the effect of antihypertensive treatment in clinical practice.

Resistant hypertension: diagnosis and management

The incidence of resistant hypertension, the failure to reduce blood pressure below 140/90 mm Hg, despite the use of 3 antihypertensive medications at optimal doses including a diuretic, is estimated to be less than 5% of the hypertensive population. Resistant hypertension increases the risk of stroke, myocardial infarction, congestive heart failure, and renal failure. Evaluation of the patient with resistant hypertension should include 24-hour ambulatory blood pressure monitoring or home measurements and a limited search for secondary causes. Treatment should focus on optimizing the drug regimen in a logical way, based on the patient's comorbidities and tolerability. Long-acting, well-tolerated once-daily medications are preferred, and the regimen should include in sequence a diuretic, beta-blocker, angiotensin-converting enzyme/angiotensin receptor-blocker inhibitors, and a calcium-channel blocker. This article reviews the definitions and causes and provides specific recommendations for the evaluation and management of patients with this life-threatening condition.