Inter-arm blood pressure difference and mortality: a cohort study in an asymptomatic primary care population at elevated cardiovascular risk

Admission Left-Arm Systolic Blood Pressure and In-Hospital Mortality After Acute Type A Aortic Dissection Repair

AIM

Admission systolic blood pressure is a significant predictor of in-hospital mortality in patients with acute type A aortic dissection (ATAAD). While previous studies have focussed on recording the highest blood pressure value from both arms, this study aimed to evaluate the associations between blood pressure in bilateral arms and in-hospital mortality.

METHODS

Data were analysed from 262 patients with ATAAD treated at a single centre. The relationship between bilateral arm blood pressure upon admission and in-hospital mortality was assessed in a logistic regression model. To comprehensively evaluate potential non-linear relationships, the association between admission bilateral systolic blood pressure (SBP) and the risk of in-hospital mortality was analysed using restricted cubic splines on a continuous scale.

RESULTS

Mean age was 53.6±12.5 years and 194 (74.0%) were male. Baseline and operative data showed that ages, body mass index, smoking, left-arm SBP, left-arm diastolic blood pressure (DBP), right-arm SBP, right-arm DBP, syncope, cerebral/cardiac ischaemia, retrograde brain perfusion, Bentall procedure, coronary artery bypass grafting, and aortic valve replacement significantly differed among the left-arm SBP tertiles. In-hospital mortality was 17.6% (46 of 262). Restricted cubic splines demonstrated that the relationship between presenting left-arm SBP and in-hospital mortality followed a U-shaped curve, whereas non-linearity was not detected in the right arm.

CONCLUSION

This study found a U-shaped association between admission left-arm SBP and in-hospital mortality in ATAAD surgery patients, whereas a non-linearity relationship was not detected for right-arm SBP. Low left-arm SBP independently correlated with increased in-hospital mortality, underscoring the significance of bilateral blood pressure differences in ATAAD prognosis.

Prevalence of interarm blood pressure difference is notably higher in women; the Viborg population-based screening program (VISP)

BACKGROUND

Bilateral blood pressure (BP) measurement is important in cardiovascular prevention for identifying systolic interarm BP difference (IAD) and hypertension. We investigated sex-stratified IAD prevalence and its associations and coexistence with screen-detected peripheral atherosclerosis and hypertension. Furthermore, we determined the proportion misclassified as non-hypertensive when using the lower versus the higher reading arm.

METHODS

This sub-study formed part of the Viborg Screening Program (VISP), a cross-sectorial population-based cardiovascular screening programme targeting 67-year-old Danes. VISP includes screening for peripheral atherosclerosis (lower extremity arterial disease and carotid plaque), abdominal aortic aneurysm, hypertension, diabetes mellitus, and cardiac disease. Self-reported comorbidities, risk factors, and medication use were also collected. Among 4,602 attendees, 4,517 (82.1%) had eligible bilateral and repeated BP measurements. IAD was defined as a systolic BP difference ≥ 10 mmHg. IAD-associated factors (screening results and risk factors) were estimated by logistic regression; proportional coexistence was displayed by Venn diagrams (screening results).

RESULTS

We included 2,220 women (49.2%) and 2,297 men (50.8%). IAD was more predominant in women (26.8%) than men (21.0%) (p < 0.001). This disparity persisted after adjustment [odds ratio (OR) 1.53; 95% confidence interval (CI) 1.32-1.77]. No other association was recorded with the conditions screened for, barring potential hypertension: BP 140-159/90-99 mmHg (OR 1.68, 95% CI 1.44-1.97) and BP ≥ 160/100 mmHg (OR 1.82, 95% CI 1.49-2.23). Overall, IAD and BP ≥ 160/100 mmHg coexistence was 4% in women and 5% in men; for BP ≥ 140/90 mmHg, 13% and 14%, respectively. Among those recording a mean BP ≥ 140/90 mmHg in the higher reading arm, 14.5% of women and 15.3% of men would be misclassified as non-hypertensive compared with the lowest reading arm.

CONCLUSION

Female sex was an independent factor of IAD prevalence but not associated with other arterial lesions. Approximately 15% needed reclassification according to BP ≥ 140/90 mmHg when the lower rather than the higher reading arm was used; verifying bilateral BP measurements improved detection of potential hypertension. In future, the predictive value of sex-stratified IAD should be assessed for cardiovascular events and death to verify its potential as a screening tool in population-based cardiovascular screening.

TRIAL REGISTRATION FOR VISP

NCT03395509:10/12/2018.

Prevalence and factors associated with inter-arm systolic and diastolic blood pressure differences: results from the baseline Fasa Adult's Cohort Study (FACS)

BACKGROUND

One of the modifiable risk factors for cardiovascular diseases is the inter-arm blood pressure difference (IAD), which can be easily measured. This study aimed to determine the prevalence and factors related to the Iranian population's inter-arm differences in systolic and diastolic blood pressure.

METHOD

This cross-sectional study was conducted on the baseline data of participants who had Iranian nationality, were at least 1 year of residence in the area, aged within the age range of 35-70 years, and willed to participate from the Fasa Persian Adult Cohort Study (FACS). IAD for systolic and diastolic blood pressure was measured and categorized into two groups of difference < 10 and ≥ 10 mmHg. Logistic regression was used to model the association between independent variables and IAD.

RESULTS

The prevalence of systolic and diastolic IAD ≥ 10 mmHg was 16.34% and 10.2%, respectively, among 10,124 participants. According to the multivariable logistic regression models, age (adjusted odds ratio (aOR): 1.019 [95% CI: 1.013, 1.025]), body mass index (BMI) (aOR: 1.112 [95% CI: 1.016, 1.229]), having type 2 diabetes (aOR Yes/No: 1.172 [95% CI: 1.015, 1.368]), having chronic headaches (aOR Yes/No: 1.182 [95% CI: 1.024, 1.365]), and pulse rate (aOR: 1.019 [95% CI: 1.014, 1.024]) significantly increased the odds of systolic IAD ≥ 10 mmHg. Additionally, high socio-economic status decreased the odds of systolic IAD ≥ 10 mmHg (aOR High/Low: 0.854 [95% CI: 0.744, 0.979]). For diastolic IAD, age (aOR: 1.112 [95% CI: 1.015, 1.210]) and pulse rate (aOR: 1.021 [95% CI: 1.015, 1.027]) significantly increased the odds of diastolic IAD ≥ 10 mmHg. Moreover, high socioeconomic status decreased the odds of diastolic IAD ≥ 10 mmHg (aOR High/Low: 0.820 [95% CI: 0.698, 0.963]).

CONCLUSION

The noticeable prevalence of systolic and diastolic IAD in general population exhibits health implications due to its' association with the risk of cardiovascular events. Sociodemographic and medical history assessments have potentials to be incorporated in IAD risk stratification and preventing programs.

Hypertension management in primary health care: a survey in eight regions of Sweden

PURPOSE

To explore hypertension management in primary healthcare (PHC).

DESIGN

Structured interviews of randomly selected PHC centres (PHCCs) from December 2019 to January 2021.

SETTING

Seventy-six PHCCs in eight regions of Sweden.

MAIN OUTCOME MEASURES

Staffing and organization of hypertension care. Methods of measuring blood pressure (BP), laboratory tests, registration of co-morbidities and lifestyle advice at diagnosis and follow-up.

RESULTS

The management of hypertension varied among PHCCs. At diagnosis, most PHCCs (75%) used the sitting position at measurements, and only 13% routinely measured standing BP. One in three (33%) PHCCs never used home BP measurements and 25% only used manual measurements. The frequencies of laboratory analyses at diagnosis were similar in the PHCCs. At follow-up, fewer analyses were performed and the tests of lipids and microalbuminuria decreased from 95% to 45% (p < 0.001) and 61% to 43% (p = 0.001), respectively. Only one out of 76 PHCCs did not measure kidney function at routine follow-ups. Lifestyle, physical activity, food habits, smoking and alcohol use were assessed in ≥96% of patients at diagnosis. At follow-up, however, there were fewer assessments. Half of the PHCCs reported dedicated teams for hypertension, 82% of which were managed by nurses. There was a great inequality in the number of patients per tenured GP in the PHCCs (median 2500; range 1300-11300) patients.

CONCLUSIONS

The management of hypertension varies in many respects between PHCCs in Sweden. This might lead to inequity in the care of patients with hypertension.

The predictive value of interarm systolic blood pressure differences in patients with vascular disease: Sub-analysis of the COMPASS trial

BACKGROUND AND AIMS

Systolic blood pressure interarm difference (IAD) predicts cardiovascular morbidity and mortality in primary prevention populations. We examined the predictive value of IAD and the effects of treatment with the combination of rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily versus aspirin 100 mg once daily according to IAD in patients with chronic coronary artery disease or peripheral artery disease.

METHODS

COMPASS trial patients with IAD <15 mmHg and IAD >15 mmHg were compared with respect to thirty-month incidence risk of: 1) composite of stroke, myocardial infarction, or cardiovascular death (MACE), 2) composite of acute limb-ischemia or vascular amputation (MALE), 3) composite of MACE or MALE, and 4) effects of treatment with the combination versus aspirin alone on these outcomes.

RESULTS

24,539 patients had IAD<15 mmHg and 2,776 had IAD ≥15 mmHg. Relative to patients with IAD ≥15 mm Hg, those with IAD<15 mmHg had similar incidence rates for all measured outcomes including the composite of MACE or MALE (HR 1.12 [95% CI: 0.95 to 1.31], p = 0.19), with the exception of stroke (HR 1.38 [95% CI: 1.02 to 1.88], p = 0.04). Compared to aspirin alone, the combination consistently reduced the composite of MACE or MALE in both IAD <15 mmHg (HR 0.74 [95% CI: 0.65-0.85], p < 0.0001, ARR = -23.1) and IAD>15 mmHg (HR 0.65 [95% CI: 0.44-0.96], p = 0.03; ARR = -32.6, p interaction = 0.53) groups.

CONCLUSIONS

Unlike primary prevention populations, measuring IAD for risk stratification purposes does not appear to be useful in patients with established vascular disease.

Combined effect of inter-arm systolic blood pressure difference and carotid artery plaque on cardiovascular diseases and mortality: A prospective cohort study

OBJECTIVES

Previous studies have confirmed the relations between inter-arm systolic blood pressure difference (IASBPD) and carotid artery plaque with the risk of cardiovascular diseases (CVD). But it is unclear whether the combined effect of IASBPD and carotid artery plaque further increases the risk of CVD and all-cause mortality.

MATERIALS AND METHODS

We enrolled 4,970 participants (≥40 years old) in the prospective Kailuan study. All participants underwent dual-arm blood pressure and carotid artery ultrasounds. IASBPD was the absolute value of the difference between dual-arm blood pressure. All the participants were divided into four groups according to their IASBPD levels and the presence or absence of carotid artery plaque and Cox proportional hazards models were used to calculate the hazard ratios (HRs) and 95% confidence interval (CI) for incident CVD and all-cause mortality.

RESULTS

During a median follow-up of 7 years, 179 CVD events and 266 deaths occurred. Multivariable Cox Regression showed that participants with IASBPD ≥ 10 mmHg and plaque had a significantly higher incidence of CVD, cerebral infarction (CI), and myocardial infarction (10, 7.27, and 1.36%, respectively). After adjusting for covariates, the IASBPD ≥ 10 mmHg and carotid plaque group significantly increased risks for CVD (HR 2.38; 95% CI, 1.40∼4.05), CI (HR, 2.47; 95% CI, 1.31∼4.67), and all-cause mortality (HR, 2.08; 95% CI, 1.20∼3.59).

CONCLUSION

Our study indicated that the combination of IASBPD and carotid artery plaque was associated with incident CVD and all-cause mortality.

Simultaneously measured inter-arm blood pressure difference is not associated with pulse wave velocity in a clinical dataset of at-risk hypertensive patients

Recent analysis of systolic inter-arm differences in blood pressure from the INTERPRESS-IPD Collaboration suggest an association with increased all-cause mortality, cardiovascular mortality and cardiovascular events. Previous studies have demonstrated associations with other risk parameters. We aimed to reproduce these associations in a cohort of 199 treated, at-risk hypertensive patients with pulse wave velocity (PWV) as a surrogate marker of cardiovascular (CV) damage. Simultaneously measured inter-arm blood pressure (BP) differences, 24 hour ambulatory BP and PWV were measured in 199 treated patients from a tertiary hospital hypertension outpatient clinic. Associations between systolic inter-arm BP difference and PWV were analyzed with uni- and multi-variate regression models. Out of 199 participants, 90 showed an inter-arm BP difference of more than 5 mmHg. The inter-arm difference was not associated with PWV. Furthermore, neither observed single BP measurements nor 24 hour ambulatory BP was associated with inter-arm BP differences. In our clinical patient cohort we failed to observe an association between inter-arm BP differences and PWV. Mode of assessment, study design and the sample characteristics of this treated, hypertensive cohort may have contributed to the negative findings. The limited sample size of the study poses a challenge to the detection of smaller effects in our study.

Inter-arm blood pressure difference as a tool for predicting coronary artery disease severity

BACKGROUND

Patients with severe atherosclerosis have been found to exhibit considerable changes in blood pressure (BP) between arms. The objective of our study was to investigate the predictive value of interarm blood pressure difference (IABPD) for coronary artery disease (CAD) severity.

METHODS

It was a cross-sectional study conducted in the Department of Cardiology, Chittagong Medical College Hospital, Chattogram from May 2020 to November 2020. The study conveniently selected 110 individuals who visited the department for a coronary angiography during the study period. The BP of both arms were synchronously measured 1-2 days before the coronary angiography and IABPD were calculated. After coronary angiography, two blinded interventional cardiologists visually estimated the amount of coronary artery obstruction and determined the Gensini score.

RESULTS

Among the participants, more than three-fourths of the patients were above 50 years of age (64.66%), and the majority were male (86.67%). 14.7% of participants had no occlusion in their coronary artery, 38.0% of participants had insignificant occlusion, 26.7% participants had mild occlusion, 10.3% participants had moderate occlusion, 3.3% participants had significant occlusion and 6.0% participants had total occlusion. Corrected pulse IABPD (cIABPDpulse) showed the greatest area under the receiver operating characteristic curve (0.73) for predicting a high Gensini score (>median). Multiple regression analysis revealed a significant relationship between corrected systolic IABPD (cIABPDsys) and the Gensini score (B=0.057, p<0.001).

CONCLUSION

The differences in BP between the arms were found to be having a strong positive correlation with CAD severity.

Arterial stiffness and contralateral differences in blood pressure: The Atherosclerosis Risk in Communities (ARIC) study

A large interarm difference in brachial systolic blood pressure (SBP) (≥10 or ≥15 mmHg) is strongly associated with elevated cardiovascular events and mortality. Evidence demonstrating whether such contralateral differences in SBP occur in ankle blood pressure and its association with arterial stiffness is scarce. The aims of this study were to characterize arm and ankle contralateral SBP differences in a sample of community‐dwelling older adults (5077), and to determine whether this difference is associated with arterial stiffness assessed by pulse wave velocity (PWV) between the heart and ankle (haPWV), femoral artery and ankle (faPWV), and brachial artery and ankle (baPWV) in the right and left sides. Prevalence of interarm SBP differences ≥10 and ≥15 mmHg was 5.1% and .7%, respectively; the corresponding prevalence for interankle SBP was 24.9% and 12.0%. Higher BMI and lower ankle‐brachial index (ABI) were significantly correlated with greater interarm SBP differences. Increased age, higher BMI, lower ABI, and greater contralateral differences in haPWV, faPWV, and baPWV were significantly correlated to greater interankle SBP differences. Interankle SBP difference ≥15 mmHg was significantly associated with contralateral differences of >80 cm/s in haPWV (OR = 1.94 [95% CI = 1.52–2.49]), >165 cm/s in faPWV (OR = 1.64 [95% CI = 1.27–2.12]), and >240 cm/s in baPWV (OR = 2.43 [95% CI = 1.94–3.05]). The associations remained significant after adjustment for age, sex, race, BMI, smoking status, and ABI. Compared with interarm differences, interankle differences in SBP are common in older adults. The magnitude of interankle, but not interarm, differences in SBP is associated with various measures of arterial stiffness.

Association between four-limb blood pressure differences and arterial stiffness: a cross-sectional study

OBJECTIVES

Although inter-arm blood pressure difference (IAD) and inter-ankle blood pressure difference (IAND) have been shown to be associated with cardiovascular disease, controversy remains. In this study, we investigated the prevalence of IAD and IAND as well as the correlation with arterial stiffness and systolic blood pressure in a large number of the Chinese population.

METHODS

The four-limb blood pressure, IAD, IAND, brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) of 12,176 participants have been measured. Multivariate logistic regression analysis was used to analyze the relationship of the increase in IAD/IAND with arterial stiffness and blood pressure. Reporting adheres to the STROBE guidelines.

RESULTS

In 12,176 participants, 1832 (15%) subjects had an IAD≥10 mmHg, 663 (5%) had an IAD≥15 mmHg, and 291 (2%) had an IAD≥20 mmHg. Correspondingly, 4548 (37%) had an IAND≥10 mmHg, 2706 (22%) had an IAND≥15 mmHg, and 1706 (14%) had an IAND≥20 mmHg. baPWV was significantly higher in those with an IAD≥10 mmHg (1881 ± 487 cm/s vs. 1943 ± 508 cm/s, P = 0.036) and IAND≥10 mmHg (1850 ± 476 cm/s vs. 1955 ± 509 cm/s, P = 0.000). Compared to others, those with IAD or IAND≥10 mmHg had higher systolic blood pressure (SBP), higher prevalence of hypertension, larger male gender ratio, bigger body mass index, higher pulse rate and lower ABI (P < 0.001 for all). A significant association with baPWV was observed for IAND≥10 mmHg (OR = 1.117; 95%CI: 1.039-1.201; P = 0.003) not for IAD≥10 mmHg (OR = 0.771; 95%CI: 0.699-0.851; P = 0.000) in multivariate logistic regression analysis.

CONCLUSIONS

Limb blood pressure differences were closely related to arterial stiffness and systolic blood pressure, allowing for a more comprehensive assessment of cardiovascular risk.

The relation between inter arm blood pressure difference and presence of cardiovascular disease: a review of current findings

Raised inter arm blood pressure difference (IABPD) is already well-known as a clinical sign of peripheral arterial diseases including aortic dissection and subclavian stenosis. However, there are several other diseases associated with high IABPD. Therefore, this study aimed to review the association between increased IABPD and the presence of lethal health conditions, the possible mechanisms behind this relationship, and its contributing risk factors. Significant IABPD has been observed in patients with atherosclerotic plaques, peripheral artery disease, coronary artery disease, and chronic kidney disease. Patients with high IABPD are also at more risk of left ventricular hypertrophy that may affect long-term cardiac function. Besides, brain injuries such as stroke, dementia, and Alzheimer's disease has been related to increased IABPD. Considering that raised IABPD is associated with multiple cardiovascular diseases and other organ damage, IABPD detection may be accurate for the early diagnosis and screening of these life-threatening diseases and help manage them better.

Assessment of blood pressure skills and belief in clinical readings

Background

Accurate blood pressure (BP) measurement is essential for the diagnosis and management of hypertension. In clinical practice, BP is estimated using noninvasive methods with significant variability of application of guidelines in clinical practice, impacting the accuracy and certainty of BP measurements.

Objective

We sought to assess how BP is measured in clinical practice.

Methods

A survey was administered through professional societies that included predominantly cardiologists. Assessment of adherence to guideline recommendations for BP assessment was measured and compared to the level of confidence in clinic BP measurement.

Results

There were 571 surveys completed. The majority of respondents were cardiologists (61.1%), with 47 preventive cardiologists. BP was routinely checked in both arms by 53% at the initial visit, 48% check BP once each visit, and 64% wait 5 min before initial BP assessment. Automated BP assessment is used by 58% respondents. The majority (83%) trust their BP readings, and those who trust their BP readings are more likely to perform the initial BP assessment themselves, compared to those who do not trust the clinic BP readings (30.2% vs. 13.6%, P = 0.009). Accurate BP measurement is performed by 23% of cardiologists, and more likely performed accurately by a preventive cardiologist (38.3%) compared with other cardiologists (20.0%, P = 0.007). Accurate BP measurement is more likely for those who perform the initial BP themselves rather than any other staff (36.8% vs. 17.9%; P<0.001); and for those who repeat BP manually (80% vs. 54%; P<0.001), compared to those who do not measure BP accurately. Despite the inaccuracy of BP measurement, there is a high level of confidence in the BP readings.

Conclusions

Accurate BP assessment continues to remain suboptimal in clinical practice. Reliability of BP assessment requires education, identifying barriers to implementation of recommendations and engagement of the entire team to improve BP assessment.

Lack of Association between Interarm Systolic Blood Pressure Difference and Coronary Artery Disease in Patients Undergoing Elective Coronary Angiography

Aim

Peripheral vascular disease (PVD) and coronary artery disease (CAD) are, in many cases, asymptomatic and not usually diagnosed. The timely diagnosis of peripheral vascular diseases can act as an indicator or practical evidence of CAD. Therefore, this study was conducted to determine the relationship between interarm systolic blood pressure difference (IASBPD) and severity and number of coronary artery stenosis.

Methods

The samples in this cross-sectional study consisted of 578 patients who were candidates for coronary angiography, with an average age of 57.5 ± 10.5 years. Patients were classified according to CAD and number and severity of coronary artery stenosis. The relationship between IASBPD and presence or lack of CAD as well as the number and severity of coronary artery stenosis was studied. The sensitivity, specificity, and positive predictive value of IASBPD index were calculated for the detection of CAD using the Kappa coefficient.

Results

There was no statistically significant relationship between IASBPD, CAD, and severity and number of coronary artery stenosis. This index had low sensitivity and predictive value in the diagnosis of CAD and stenosis in coronary arteries in comparison with angiography.

Conclusion

The results showed that the IASBPD index cannot be a valid criterion for the diagnosis of CAD as well as the number and severity of coronary artery stenosis. More studies with larger sample sizes and different designs are needed in this regard to achieve more conclusive results.

Inter-arm difference in blood pressure in patients referred to tertiary hypertension center: Prevalence, risk factors, and relevance to physicians

The prevalence of inter-arm BP difference is high in hypertension and is associated with adverse cardiovascular outcomes. We performed a retrospective chart review of prevalent patients in the Ottawa Hospital Hypertension Center to assess for prevalence, risk factors, and whether finding of inter-arm BP difference >10 mmHg leads to investigations of the aorta and aortic arch. Inter-arm BP difference among 493 patients was present in 16.2% (95% confidence interval [CI]13.3-19.9%), and it was associated with presence of peripheral arterial disease. Physicians did not investigate ascending aorta and aortic arch for causes of the clinically significant inter-arm BP difference.

Associations Between Systolic Interarm Differences in Blood Pressure and Cardiovascular Disease Outcomes and Mortality: Individual Participant Data Meta-Analysis, Development and Validation of a Prognostic Algorithm: The INTERPRESS-IPD Collaboration

Systolic interarm differences in blood pressure have been associated with all-cause mortality and cardiovascular disease. We undertook individual participant data meta-analyses to (1) quantify independent associations of systolic interarm difference with mortality and cardiovascular events; (2) develop and validate prognostic models incorporating interarm difference, and (3) determine whether interarm difference remains associated with risk after adjustment for common cardiovascular risk scores. We searched for studies recording bilateral blood pressure and outcomes, established agreements with collaborating authors, and created a single international dataset: the Inter-arm Blood Pressure Difference - Individual Participant Data (INTERPRESS-IPD) Collaboration. Data were merged from 24 studies (53 827 participants). Systolic interarm difference was associated with all-cause and cardiovascular mortality: continuous hazard ratios 1.05 (95% CI, 1.02-1.08) and 1.06 (95% CI, 1.02-1.11), respectively, per 5 mm Hg systolic interarm difference. Hazard ratios for all-cause mortality increased with interarm difference magnitude from a ≥5 mm Hg threshold (hazard ratio, 1.07 [95% CI, 1.01-1.14]). Systolic interarm differences per 5 mm Hg were associated with cardiovascular events in people without preexisting disease, after adjustment for Atherosclerotic Cardiovascular Disease (hazard ratio, 1.04 [95% CI, 1.00-1.08]), Framingham (hazard ratio, 1.04 [95% CI, 1.01-1.08]), or QRISK cardiovascular disease risk algorithm version 2 (QRISK2) (hazard ratio, 1.12 [95% CI, 1.06-1.18]) cardiovascular risk scores. Our findings confirm that systolic interarm difference is associated with increased all-cause mortality, cardiovascular mortality, and cardiovascular events. Blood pressure should be measured in both arms during cardiovascular assessment. A systolic interarm difference of 10 mm Hg is proposed as the upper limit of normal. Registration: URL: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42015031227.

Characterization of resting and exercise inter-arm differences in SBP to isometric handgrip exercise in males and females

A large inter-arm difference (IAD; ≥10 mmHg) in SBP is linked to cardiovascular and peripheral vascular disease, hypertension, and premature mortality. Exercise-induced IAD (eIAD) is related to resting IAD, and acute aerobic activity alters eIAD and reduces IAD in recovery. Isometric handgrip exercise (IHE) affects blood pressure (BP), though the eIAD response to IHE is unknown. Further, the eIAD response may differ between males and females.

OBJECTIVES

To characterize the eIAD response to IHE in males and females.

METHODS

On visit 1, participants (16 females and 15 males, aged 18-35 years) completed three maximal voluntary isometric contractions (MVIC) per arm. On visit 2, before IHE, a series of three simultaneous, bilateral BP measures were averaged at rest. During IHE, participants maintained handgrip at 20% of MVIC for 2 minutes (arm randomly assigned), at which time bilateral BP was measured (IHE) during exercise and subsequent recovery (REC1 and REC2). Repeated-measures analysis of variance assessed eIAD and SBP (time × sex).

RESULTS

IHE increased absolute eIAD (4 mmHg). Differences in relative eIAD were observed at IHE and REC2 based on resting IAD status (P < 0.05). Females only had an exaggerated SBP and pulse pressure response in the working arm.

CONCLUSION

Acute IHE was shown to augment eIAD. Further eIAD and resting IAD were related. Acute IHE induced different bilateral responses between males and females, though the impact of sex on eIAD warrants further investigation. Future studies should address the effects of repeated bouts of IHE, which may benefit individuals with a large resting IAD.

Systolic inter-arm blood pressure difference and risk of cognitive decline in older people: a cohort study

BACKGROUND

Systolic inter-arm difference in blood pressure (IAD) and cognitive decline are both associated with cardiovascular disease; therefore, it was hypothesised that IAD may be predictive of cognitive decline.

AIM

To examine associations of IAD with cognitive decline in a community population.

DESIGN AND SETTING

A prospective study of older Italian adults enrolled in the InCHIANTI study.

METHOD

Univariable and multivariable associations of IAD were explored with declines in mini mental state examination (MMSE) scores, Trail Making Test A and B scores, and a composite outcome representing substantial decline in any of these scores. Backward stepwise regression was used to adjust observed associations of IAD with cognitive decline.

RESULTS

The rate of decline for MMSE scores in 1133 participants was greater with IAD ≥5 mmHg or ≥10 mmHg. On univariable analyses continuous IAD was associated with the composite outcome (odds ratio [OR] 1.16 per 5 mmHg of IAD, 95% confidence interval [CI] = 1.02 to 1.31). Substantial decline in MMSE score was seen with IAD ≥5 mmHg (OR 1.41, 95% CI = 1.03 to 1.93), and in the composite outcome with IAD ≥5 mmHg (OR 1.44, 95% CI = 1.10 to 1.89) or ≥10 mmHg (OR 1.39, 95% CI = 1.03 to 1.88). After multivariable adjustment, an IAD ≥ 5 mmHg remained associated with reductions in the composite outcome, reflecting declining cognitive performance (OR 1.46, 95% CI = 1.05 to 2.03).

CONCLUSION

An IAD ≥5 mmHg is associated with cognitive decline in a representative older population. Given that systolic inter-arm differences in blood pressure are easily measured, confirmation of these findings could inform individualised treatment for the prevention of cognitive decline and dementia.

Mathematical Model Based on the Shape of Pulse Waves Measured at a Single Spot for the Non-Invasive Prediction of Blood Pressure

Background: Continuous non-invasive blood pressure (BP) measurement is a desired virtue in clinical practice. Unfortunately, current systems do not allow one for continuous, reliable BP measurement for more than a few hours per day, and they often require a complicated set of sensors to provide the necessary biosignals. Therefore we investigated the possibility of proposing a computational model that would predict the BP from pulse waves recorded in a single spot. Methods: Two experimental circuits were created. One containing a simple plastic tube for model development and a second with a silicone molded patient-specific arterial tree model. The first model served for the measuring of pulse waves under various BP (70–270 mmHg) and heart rate (60–190 beats per minute) values. Four different computational models were used to estimate the BP values from the diastolic time. The most accurate model was further validated using data from the latter experimental circuit containing a molded patient-specific silicone arterial tree. The measured data were averaged over a window of one, three, and five cycles. Two models based on pulse arrival time (PAT) were also analyzed for comparison. Results: The most accurate model exhibits a correlation coefficient of r = 0.967. The Bland–Altman plot revealed standard deviations (SD) between the model predictions and measurement of 10, 8.3, and 7.5 mmHg for the systolic BP and 8.7, 7 and 6.3 mmHg for the diastolic BP (both pressures calculated for the averaging windows of one, three, and five cycles, respectively). The best of the used PAT based model exhibited a SD of 17, 16, and 15 mmHg for the systolic BP and 14, 13, and 12 mmHg for the diastolic BP for the same averaging windows. Discussion: The proposed model showed its capability to predict BP accurately from the shape of the pulse wave measured at a single spot. Its SD was about 50% lower compared to the PAT based models which met the requirements of the Association for the Advancement of Medical Instrumentation.

Association between an elevated inter-arm systolic blood pressure difference, the ankle-brachial index, and mortality in patients with diabetes mellitus

OBJECTIVES

To estimate the prevalence of an inter-arm blood pressure difference greater than 10mmHg in patients with type 2 diabetes, and the association of this measurement with the presence of a low ankle-brachial index and mortality at 5-year follow-up.

METHOD

A validated blood pressure measurement protocol was used. The blood pressure was calculated for each arm to obtain mean systolic differences. Peripheral arterial disease was confirmed by an ankle-arm index less than 0.9. The medical history of the patient was reviewed in the computerized clinical notes after 5 years of follow-up.

RESULTS

The study included 139 patients with a mean age of 70.1 years (49% male), and a mean duration of diabetes mellitus of 10.8 years. A total of 50 (36%) patients had an inter-arm systolic blood pressure difference greater than 10mmHg. Patients with an inter-arm systolic blood pressure greater than 10mmHg had lower ankle-arm index (0.91±0.30 vs. 1.04±0.28, P=0.005), and higher mortality rates from all causes (48.0% vs. 28.9%; hazard ratio 1.64; 95% confidence interval: 1.06-2.53; P=0.03), compared with those with lower inter-arm systolic blood pressure difference.

CONCLUSION

A high proportion of patients with type 2 diabetes have an elevated systolic blood pressure difference between arms. A significant relationship was found between elevated inter-arm systolic blood pressure difference, lower ankle-brachial index and greater all-cause mortality.

Effect of inter-arm blood pressure differences on outcomes after percutaneous coronary intervention

BACKGROUND

We investigated the effect of inter-arm blood pressure differences (IABPD) on the percutaneous coronary intervention (PCI) outcomes of patients with coronary artery diseases.

METHODS

We retrospectively reviewed the data of blood pressures measured simultaneously in the bilateral arms of 855 patients (560 males) who underwent PCI with drug-eluting stents for coronary artery diseases. IABPD was defined as the difference of blood pressure in both arms. The primary outcome was the presence of major adverse cardiac events (MACE) consisting of cardiovascular death, myocardial infarction, stroke, and ischemia-driven target vessel revascularization.

RESULTS

The mean age of the included patients was 66.2 ± 11.6 years, with a mean follow-up period of 44.5 ± 26.4 months. MACE occurred in 15.2% of patients, showing a higher rate in the higher IABPD group (≥10 mmHg) than in the lower IABPD group (<10 mmHg) (22.5% vs 14.5%, p = 0.081). The difference was induced by a higher rate of ischemia-driven target vessel revascularization (17.5% vs 8.3%, p = 0.011). The Kaplan-Meier survival analysis revealed a greater incidence of MACE in patients with a higher IABPD (log rank p = 0.054). The Cox proportional hazard analysis showed that IABPD was an independent predictor of long-term MACE (hazard ratio, 1.028; 95% confidence interval, 1.002-1.055; p = 0.037), along with age, diabetes mellitus, and number of implanted stents.

CONCLUSION

Among patients treated with PCI, the incidence of MACE was significantly higher in those with a higher IABPD (≥10 mmHg) than in those with a lower IABPD (<10 mmHg), which was mainly driven by ischemia-driven target vessel revascularization.

Association of 4-limb systolic blood pressure heterogeneity with peripheral artery disease and left ventricular mass index

A large interarm and interleg systolic blood pressure (SBP) difference and ankle-brachial index (ABI) <0.9 were associated with peripheral artery disease and left ventricular hypertrophy. These 3 parameters were derived from 4-limb SBP data. However, there is no study to assess clinical significance of SBP heterogeneity in 4 limbs. The aim of this study was to evaluate the association of 4-limb SBP standard deviation (SD) with peripheral vascular parameters and echocardiographic data in patients with or without clinical findings of peripheral artery disease.A total of 1240 patients were included, of whom 1020 had no clinical evidence of overt peripheral artery disease. The 4-limb blood pressures, brachial-ankle pulse wave velocity, and ABI were measured simultaneously by an ABI-form device.In the multivariable linear regression analysis, increased left ventricular mass index (LVMI), ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg (P ≤ .030) were associated with increased 4-limb SBP SD. Additionally, a subgroup multivariable linear regression analysis in 1020 patients without ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg found 4-limb SBP SD still had a positive correlation with LVMI (P < .001).In addition to significant association with ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg, 4-limb SBP SD was positively correlated with LVMI in the multivariable linear regression analysis in all study patients. Furthermore, in the subgroup of patients without clinical evidence of peripheral artery disease, 4-limb SBP SD still had a positive correlation with LVMI. Hence, assessment of 4-limb SBP heterogeneity is useful in identification of high-risk group of peripheral artery disease and/or increased LVMI, irrespective of the presence of overt peripheral artery disease.

Inter-Arm Blood Pressure Difference in Diabetes Mellitus and Its Preferential Association with Peripheral Artery Disease

Aim: Inter-arm blood pressure difference (IAD) is known to be associated with a composite of cardiovascular disease (CVD) and with CVD risk factors. However, only limited information is available regarding the contribution of diabetes mellitus to IAD and the association of IAD with individual CVDs, such as coronary artery disease (CAD), stroke, and peripheral artery disease (PAD).

Methods: We addressed these issues in this cross-sectional study of 2580 participants who had simultaneous blood pressure measurements in both arms using an automated device.

Results: Compared with 1,264 nondiabetic subjects, 1316 patients with diabetes mellitus had a greater IAD (P = 0.01) and a higher prevalence of IAD of ≥ 10 mmHg (8.4% vs. 5.4%, P = 0.002). However, such difference was not significant after the adjustment for potential confounders. Among CAD, stroke, and PAD, only PAD was significantly associated with IAD in a model adjusted for the CVD risk factors. Age was found to modify the association between IAD and PAD, with the association being more prominent in the younger subgroup.

Conclusion: Thus, diabetes mellitus itself was not an independent factor associated with IAD. A larger IAD was preferentially associated with the presence of PAD, and this association was modified by age.

Longitudinal association between adiposity and inter-arm blood pressure difference

This is the first longitudinal study evaluating whether adiposity is associated with inter-arm blood pressure difference. We evaluated 714 overweight/obese individuals aged 40-65 years over a 3-year follow-up. Systolic and diastolic blood pressures were measured in both arms simultaneously using an automated machine. Linear regression assessed the associations of body mass index, fat %, waist, neck, thigh, and arm circumferences (cm), with absolute inter-arm differences in systolic (IAS) and diastolic (IAD) blood pressure (mm Hg). Poisson regression was used for binary outcomes (IAS and IAD ≥ 10 mm Hg). All models were adjusted for age, gender, smoking, physical activity, and HOMA-IR. Adiposity measures were associated with increased IAS and IAD (β range: 0.09-0.20 and 0.09-0.30). Neck circumference showed the strongest association with IAS (β = 0.20, 95% CI: 0.03, 0.37) and IAD (β = 0.30, 95% CI: 0.12, 0.47); arm circumference showed a similar association with IAS, but lower with IAD. Highest quartiles of BMI, thigh, and arm showed significant associations with IAS (IRR: 2.21, 2.46 and 2.70). Highest quartiles of BMI, waist, neck, and arm circumferences were significantly associated with IAD (IRR: 2.38, 2.68, 4.50 and 2.24). If the associations are corroborated in other populations, adiposity may be an important modifiable risk factor for inter-arm blood pressure difference with a large potential public health impact.

Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association

The accurate measurement of blood pressure (BP) is essential for the diagnosis and management of hypertension. This article provides an updated American Heart Association scientific statement on BP measurement in humans. In the office setting, many oscillometric devices have been validated that allow accurate BP measurement while reducing human errors associated with the auscultatory approach. Fully automated oscillometric devices capable of taking multiple readings even without an observer being present may provide a more accurate measurement of BP than auscultation. Studies have shown substantial differences in BP when measured outside versus in the office setting. Ambulatory BP monitoring is considered the reference standard for out-of-office BP assessment, with home BP monitoring being an alternative when ambulatory BP monitoring is not available or tolerated. Compared with their counterparts with sustained normotension (ie, nonhypertensive BP levels in and outside the office setting), it is unclear whether adults with white-coat hypertension (ie, hypertensive BP levels in the office but not outside the office) have increased cardiovascular disease risk, whereas those with masked hypertension (ie, hypertensive BP levels outside the office but not in the office) are at substantially increased risk. In addition, high nighttime BP on ambulatory BP monitoring is associated with increased cardiovascular disease risk. Both oscillometric and auscultatory methods are considered acceptable for measuring BP in children and adolescents. Regardless of the method used to measure BP, initial and ongoing training of technicians and healthcare providers and the use of validated and calibrated devices are critical for obtaining accurate BP measurements.

Evaluation of inter-arm difference in blood pressure as predictor of vascular diseases among urban adults in Kancheepuram District of Tamil Nadu

Introduction:

An “Inter-Arm Difference” (IAD) in blood pressure (BP) is defined as a variation in systolic BP of >10 mmHg. Various studies conducted in different population show that there are wide variations in the prevalence of IAD, which ranges from 5% to 46%. The aim of this study is to evaluate the prevalence of IAD in BP among adults and its association with risk factors.

Methods:

This community-based cross-sectional study was carried out among urban adults in Kancheepuram district. The study sample size of 1634 was calculated, and simple random sampling method was used. Data analysis was performed using SPSS software version 16. Prevalence of IAD in BP was calculated using percentages, and statistical significance was tested to look for an association.

Results:

This study shows that 26.2% were at moderate risk for vascular events with IAD in systolic BP of 10–15 mmHg and 17.3% were at high risk with IAD >15 mmHg. About 14.2% had diastolic BP difference of 10–15 mmHg indicative of moderate risk and 6.1% had a difference of >15 mmHg indicative of high risk for vascular events. The statistical significant association was found between IAD in systolic BP and risk factors such as hypertension, smoking, alcoholism, and between IAD in diastolic BP with overweight/obesity (P < 0.05).

Conclusion:

This study outcome shows that the prevalence of IAD in BP is on the higher side. Hence, specific guidelines should be brought in to practice for measuring BP in both arms to detect IAD in every health-care settings.

Interarm Systolic and Diastolic Blood Pressure Difference Is Diversely Associated With Cerebral Atherosclerosis in Noncardioembolic Stroke Patients

BACKGROUND

Interarm systolic and diastolic blood pressure differences (IASBD, IADBD) are not infrequent in various populations. Cerebral atherosclerosis, including extracranial cerebral atherosclerosis (ECAS) and intracranial cerebral atherosclerosis (ICAS), is an important risk factor for stroke. In this study, we aimed to investigate the relationship of IASBD, IADBD with presence and burden of ICAS and ECAS.

METHODS

This was a retrospective hospital-based cross-sectional study. In total, 1,063 consecutive noncardioembolic ischemic stroke patients, who were checked for bi-brachial blood pressures from ankle-brachial index and brain magnetic resonance angiographic images of cerebral arteries, were included. The IASBD and IADBD were defined as absolute value of the blood pressure difference in both arms.

RESULTS

In all included patients, patients with IASBD ≥10 and IADBD ≥10 were noted in 9.4% (100/1,063) and 5.3% (56/1,063). The patients with IASBD ≥10 mm Hg were more frequently burdened with ICAS (P = 0.001) and ECAS (P = 0.027) and patients with IADBD ≥10 mm Hg were more frequently burdened with ICAS (P = 0.042) but not ECAS (P = 0.187). Multivariate analysis after adjusting gender, age, and a P value <0.1 in univariate analysis showed IASBD ≥10 mm Hg was associated with the presence of both ECAS and ICAS [odds ratio (OR): 2.96, 95% confidence interval (CI): 1.65-5.31]. The IADBD ≥10 mm Hg was related with presence of ICAS only (OR: 1.87, 95% CI: 1.05-3.37) but not with ECAS only (OR: 1.50, 95% CI: 0.73-3.06).

CONCLUSIONS

Our study showed IASBD and IADBD were diversely associated with cerebral atherosclerosis. In noncardioembolic stroke patients with IASBD ≥10 or IADBD ≥10, the possibility of accompanying cerebral atherosclerosis should be considered.

Association of physical activity with a systolic blood pressure difference between arms in older people

AIM

A increase in interarm systolic blood pressure difference (IASBPD) is believed to lead to increased risk of cardiovascular disease and to be a predictor of future cardiovascular events. The purpose of the present study was to test the hypothesis that an increased IASBPD is associated with reduced physical activity in older people.

METHODS

Older people who used a geriatric health services facility (n = 147, mean age 83.3 years) were enrolled. The prevalence of IASBPD in individuals with different levels of physical activity and factors that have a crucial effect on IASBPD were investigated. The study participants were divided into three groups according to their physical activity; ambulant persons (group A), wheelchair users (group B) and bedridden persons (group C). Blood pressure around the both brachiums was simultaneously measured using two automated devices. An IASBPD of ≥10 mmHg was considered to be significant IASBPD.

RESULTS

The median IASBPD was 4.5 mmHg in the present study participants, and 28 participants (19.0%) had an IASBPD ≥10 mmHg. The IASBPD in group C was greater than that in group A or B. Multivariate linear regression analysis showed that physical activity was the independent predictor of IASBPD after adjustment for possible factors. Furthermore, a logistic regression analysis with the end-point of significant IASBPD showed that physical activity is an independent predictor of significant IASBPD.

CONCLUSIONS

Physical activity simply assessed by moving ability can predict IASBPD in older individuals. In older people, reduced physical activity might indicate the progression of silent or clinical atherosclerosis and an increased risk of cardiovascular disease. Geriatr Gerontol Int 2018; 18: 95-100.

Associations between interarm differences in blood pressure and cardiovascular disease outcomes: protocol for an individual patient data meta-analysis and development of a prognostic algorithm

INTRODUCTION

Individual cohort studies in various populations and study-level meta-analyses have shown interarm differences (IAD) in blood pressure to be associated with increased cardiovascular and all-cause mortality. However, key questions remain, such as follows: (1) What is the additional contribution of IAD to prognostic risk estimation for cardiovascular and all-cause mortality? (2) What is the minimum cut-off value for IAD that defines elevated risk? (3) Is there a prognostic value of IAD and do different methods of IAD measurement impact on the prognostic value of IAD? We aim to address these questions by conducting an individual patient data (IPD) meta-analysis.

METHODS AND ANALYSIS

This study will identify prospective cohort studies that measured blood pressure in both arms during recruitment, and invite authors to contribute IPD datasets to this collaboration. All patient data received will be combined into a single dataset. Using one-stage meta-analysis, we will undertake multivariable time-to-event regression modelling, with the aim of developing a new prognostic model for cardiovascular risk estimation that includes IAD. We will explore variations in risk contribution of IAD across predefined population subgroups (eg, hypertensives, diabetics), establish the lower limit of IAD that is associated with additional cardiovascular risk and assess the impact of different methods of IAD measurement on risk prediction.

ETHICS AND DISSEMINATION

This study will not include any patient identifiable data. Included datasets will already have ethical approval and consent from their sponsors. Findings will be presented to international conferences and published in peer reviewed journals, and we have a comprehensive dissemination strategy in place with integrated patient and public involvement.

PROSPERO REGISTRATION NUMBER

CRD42015031227.

Interarm blood pressure differences predict target organ damage in type 2 diabetes

Patients with type 2 diabetes mellitus are at high risk for atherosclerotic disease, and proper blood pressure measurement is mandatory. The authors examined the prevalence of an interarm difference (IAD) in blood pressure and its association with cardiovascular risk factors and organ damage (nephropathy, retinopathy, left ventricular hypertrophy, and vascular damage) in a large diabetic population. A total of 800 consecutive patients with type 2 diabetes mellitus were evaluated with an automated simultaneous bilateral device (men: 422 [52.8%]; mean age: 68.1±12.2 years). Diabetic patients with systolic IAD ≥5 and systolic IAD ≥10 mm Hg showed an increased risk of having vascular damage (adjusted odds ratios: 1.73 and 2.49, respectively) and higher pulse pressure. IAD is highly prevalent in patients with diabetes, is associated with vascular damage, even for IAD ≥5 mm Hg, and should be accurately obtained to avoid underdiagnosis and undertreatment of hypertension.

Trends in the diagnosis and management of hypertension: repeated primary care survey in South West England

BACKGROUND

Previous surveys identified a shift to nurse-led care in hypertension in 2010. In 2011 the National Institute for Health and Care Excellence (NICE) recommended ambulatory (ABPM) or home (HBPM) blood pressure (BP) monitoring for diagnosis of hypertension.

AIM

To survey the organisation of hypertension care in 2016 to identify changes, and to assess uptake of NICE diagnostic guidelines.

DESIGN AND SETTING

Questionnaires were distributed to all 305 general practices in South West England.

METHOD

Responses were compared with previous rounds (2007 and 2010). Data from the 2015 Quality and Outcomes Framework (QOF) were used to compare responders with non-responders, and to explore associations of care organisation with QOF achievement.

RESULTS

One-hundred-and-seventeen practices (38%) responded. Responders had larger list sizes and greater achievement of the QOF target BP ≤150/90 mmHg. Healthcare assistants (HCAs) now monitor BP in 70% of practices, compared with 37% in 2010 and 19% in 2007 (P<0.001). Nurse prescribers alter BP medication in 26% of practices (11% in 2010, none in 2007; P<0.001). Of the practices, 89% have access to ABPM, but only 71% report confidence in interpreting results. Also, 87% offer HBPM, with 93% of these confident in interpreting results.

CONCLUSION

In primary care BP monitoring has devolved from GPs and nurses to HCAs. One in 10 practices are not implementing NICE guidelines on ABPM and HBPM for diagnosis of hypertension. Most practices express confidence interpreting HBPM results but less so with ABPM. The need for education and quality assurance for allied health professionals is highlighted, and for training in ABPM interpretation for GPs.

Prevalence of systolic inter-arm differences in blood pressure for different primary care populations: systematic review and meta-analysis

BACKGROUND

Various prevalence figures have been reported for inter-arm differences in blood pressure (IAD); variation may be explained by differing population vascular risk and by measurement method.

AIM

To review the literature to derive robust estimates of IAD prevalence relevant to community populations.

DESIGN AND SETTING

Systematic review and meta-analysis.

METHOD

MEDLINE, Embase, and CINAHL were searched for cross-sectional studies likely to represent general or primary care populations, reporting prevalence of IAD and employing a simultaneous method of measurement. Using study-level data, pooled estimates of mean prevalence of systolic IADs were calculated and compared using a random effects model.

RESULTS

Eighty IAD studies were identified. Sixteen met inclusion criteria: pooled estimates of prevalence for systolic IAD ≥10 mmHg were 11.2% (95% confidence interval [CI] = 9.1 to 13.6) in hypertension, 7.4% (95% CI = 5.8 to 9.2) in diabetes, and 3.6% (95% CI = 2.3 to 5.0) for a general adult population (P<0.001 for subgroup differences). Differences persisted for higher cut-off values. Prevalences were lower for East Asian than for Western populations and were overestimated by sequential measurement where this could be compared with simultaneous measurement within studies (relative risk for IAD: 2.9 [95% CI = 2.1 to 4.1]). Studies with higher mean absolute systolic pressures had higher prevalences for a systolic IAD ≥10 mmHg (P = 0.04).

CONCLUSION

Prevalences of IADs rise in relation to underlying cardiovascular comorbidities of the population studied, and are overestimated threefold when sequential measurement is used. Population-specific variation in prevalences of IAD should be taken into account in delivering clinical care and in planning future studies.

Elevated heart rate and nondipping heart rate as potential targets for melatonin: a review

Elevated heart rate is a risk factor for cardiovascular and all-cause mortalities in the general population and various cardiovascular pathologies. Insufficient heart rate decline during the night, that is, nondipping heart rate, also increases cardiovascular risk. Abnormal heart rate reflects an autonomic nervous system imbalance in terms of relative dominance of sympathetic tone. There are only a few prospective studies concerning the effect of heart rate reduction in coronary heart disease and heart failure. In hypertensive patients, retrospective analyses show no additional benefit of slowing down the heart rate by beta-blockade to blood pressure reduction. Melatonin, a secretory product of the pineal gland, has several attributes, which predict melatonin to be a promising candidate in the struggle against elevated heart rate and its consequences in the hypertensive population. First, melatonin production depends on the sympathetic stimulation of the pineal gland. On the other hand, melatonin inhibits the sympathetic system in several ways representing potentially the counter-regulatory mechanism to normalize excessive sympathetic drive. Second, administration of melatonin reduces heart rate in animals and humans. Third, the chronobiological action of melatonin may normalize the insufficient nocturnal decline of heart rate. Moreover, melatonin reduces the development of endothelial dysfunction and atherosclerosis, which are considered a crucial pathophysiological disorder of increased heart rate and pulsatile blood flow. The antihypertensive and antiremodeling action of melatonin along with its beneficial effects on lipid profile and insulin resistance may be of additional benefit. A clinical trial investigating melatonin actions in hypertensive patients with increased heart rate is warranted.