A comparison of ambulatory blood pressure patterns across populations

Twenty-four-hour ambulatory blood pressure changes in older patients with essential hypertension receiving monotherapy or dual combination antihypertensive drug therapy

Objective

To evaluate the differences in 24-hour ambulatory blood pressure (BP) in older patients with hypertension treated with the five major classes of antihypertensive drugs, as monotherapy or dual combination therapy, to improve daytime and nighttime BP control.

Methods

We enrolled 1920 Chinese community-dwelling outpatients aged ≥ 60 years and compared ambulatory BP values and ambulatory BP control (24-hour BP < 130/80 mmHg; daytime mean BP < 135/85 mmHg; and nighttime mean BP < 120/70 mmHg), as well as nighttime BP dip patterns for monotherapy and dual combination therapy groups.

Results

Patients' mean age was 71 years, and 59.5% of patients were women. Calcium channel blockers (CCBs) constituted the most common (60.3% of patients) monotherapy, and renin-angiotensin system (RAS) blockers combined with CCBs was the most common (56.5% of patients) dual combination therapy. Monotherapy with beta-blockers (BB) provided the best daytime BP control. The probabilities of having a nighttime dip pattern and nighttime BP control were higher in patients receiving diuretics compared with CCBs (OR = 0.52, P = 0.05 and OR = 0.41, P = 0.007, respectively). Patients receiving RAS/diuretic combination therapy had a higher probability of having controlled nighttime BP compared with those receiving RAS/CCB (OR = 0.45, P = 0.004). Compared with RAS/diuretic therapy, BB/CCB therapy had a higher probability of achieving daytime BP control (OR = 1.27, P = 0.45).

Conclusions

Antihypertensive monotherapy and dual combination drug therapy provided different ambulatory BP control and nighttime BP dip patterns. BB-based regimens provided lower daytime BP, whereas diuretic-based therapies provided lower nighttime BP, compared with other antihypertensive regimens.

Night blood pressure responses to atenolol and hydrochlorothiazide in black and white patients with essential hypertension

BACKGROUND

Night blood pressure (BP) predicts patient outcomes. Variables associated with night BP response to antihypertensive agents have not been fully evaluated in essential hypertension.

METHODS

We sought to measure night BP responses to hydrochlorothiazide (HCTZ), atenolol (ATEN), and combined therapy using ambulatory blood pressure (ABP) monitoring in 204 black and 281 white essential hypertensive patients. Initial therapy was randomized; HCTZ and ATEN once daily doses were doubled after 3 weeks and continued for 6 more weeks with the alternate medication added for combined therapy arms. ABP was measured at baseline and after completion of each drug. Night, day, and night/day BP ratio responses (treatment - baseline) were compared in race/sex subgroups.

RESULTS

Baseline night systolic BP and diastolic BP, and night/day ratios were greater in blacks than whites (P < 0.01, all comparisons). Night BP responses to ATEN were absent and night/day ratios increased significantly in blacks (P < 0.05). At the end of combined therapy, women, blacks, and those starting with HCTZ as opposed to ATEN had significantly greater night BP responses (P < 0.01). Variables that significantly associated with ATEN response differed from those that associated with HCTZ response and those that associated with night BP response differed from those that associated with day BP response.

CONCLUSIONS

In summary, after completion of HCTZ and ATEN therapy, women, blacks, and those who started with HCTZ had greater night BP responses. Reduced night BP response and increased night/day BP ratios occured with ATEN in blacks. Given the prognostic significance of night BP, strategies for optimizing night BP antihypertensive therapy should be considered.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov identifier NCT00246519.

Interactive influences of ethnicity, endothelin-1 gene, and everyday discrimination upon nocturnal ambulatory blood pressure

BACKGROUND

Everyday discrimination scale scores are associated with increased ambulatory blood pressure (BP) and reduced nocturnal dipping, and the endothelin-1 (ET-1)/Lys198Asn polymorphism is associated with increased resting BP and exaggerated BP reactivity among African Americans compared to European Americans. Combined influences of these factors on BP control are unknown.

PURPOSE

This study tested the hypothesis of a three-way interaction between ethnicity, ET-1 carrier status, and everyday discrimination upon ambulatory BP and nocturnal dipping.

METHODS

Baseline laboratory anthropometrics and the everyday discrimination scale were completed by 352 (175 African American) young adult normotensives, followed by 24-h ambulatory BP monitoring.

RESULTS

For nocturnal dipping, multiple regression models controlling for age, sex, ethnicity, and body mass index revealed significant three-way ET-1 × everyday discrimination × ethnicity interactions. Specifically, among African American ET-1 T-allele carriers, increases in everyday discrimination led to reduced nocturnal dipping.

CONCLUSIONS

African Americans that carry the ET-1/Lys198Asn T-allele and report higher everyday discrimination scores may be at particular risk for reduced nocturnal dipping.

Night/day ratios of ambulatory blood pressure among healthy adolescents: roles of race, socioeconomic status, and psychosocial factors

BACKGROUND

Elevated nighttime blood pressure (BP) predicts hypertension and its complications in adulthood.

PURPOSE

This study aimed to assess the independent effects of race and family income on night/day BP among adolescents and to examine whether negative emotions, low positive resources, and unpleasant interactions during the day are also related.

METHODS

Healthy African American and Caucasian high school students (N = 239) wore an ambulatory BP monitor for 48 h, recorded quality of ongoing interpersonal interactions, and completed questionnaires.

RESULTS

African Americans and those with lower family income had higher night/day BP ratios. African Americans reporting greater negative emotions, lower positive resources, and more unpleasant interactions had higher night/day BP ratios.

CONCLUSIONS

Racial differences in night BP emerge by adolescence, independent of family income. African Americans, especially those high in negative emotions and low in positive resources, may be at higher relative risk for hypertension later in life in part due to elevated night BP.

Dipping status and hostility in newly diagnosed essential hypertension

AIM

Personality traits, including hostility, play an important role in the development of cardiovascular disease. Moreover, abnormalities in blood pressure circadian pattern, such as a lack of nocturnal BP fall, are related with target organ damage and increased cardiovascular risk. The aim of this study was to investigate the impact of hostility and its dimensions on dipping status, in newly diagnosed hypertensive patients.

METHODS

The study population consisted of 114 newly diagnosed untreated essential hypertensives. All participants underwent 24-hour ambulatory blood pressure monitoring (ABPM) in order to assess dipping status. Hostility was assessed by Hostility and Direction of Hostility Questionnaire (HDHQ). The study population was divided in terms of dipping status in two groups, "dippers" and "non-dippers."

RESULTS

The statistical analysis revealed that dippers presented significantly higher score of extrapunitiveness (13.2 +/- 4.9 vs 11.4 +/- 3.9, p = 0.032), as well as significantly higher score of the dimension "urge to act out hostility (AH)" (4 +/- 3 vs 3 +/- 2, p = 0.025) compared to non-dippers. Multivariate regression analysis revealed extrapunitiveness as the only independent predictor of dipping status. The odds ratio (OR) for dipping status associated with each point increase in extrapunitiveness was 0.912 (95% CI: 0.832-0.992; p = 0.048).

CONCLUSION

The present findings may suggest that hostility and its features affect the circadian variation of blood pressure in hypertensive patients, providing a promising objective for future investigations linking psychological factors and dipping status in essential hypertension.

Relationship between waking-sleep blood pressure and catecholamine changes in African-American and European-American women

BACKGROUND

A blunted decline in waking to sleep blood pressure (BP) is more common in African-American (AA) than European-American (EA) women. The causes of reduced BP 'dipping' in AA women are not known, although several factors including ethnic differences in catecholamine sensitivity have been suggested. The purpose of this study was to investigate the possible contribution of catecholamine influences on BP to ethnic differences in BP dipping in a sample of working women.

PARTICIPANTS AND METHODS

Healthy female participants wore ambulatory BP monitors over the course of 1 work day and night. Urine samples for assay of epinephrine and norepinephrine were collected at work (approximately 11.00-15.00 h), home (approximately 06.00-22.00 h) and during sleep (approximately 22.00-06.00 h). Analysis of covariance was used to assess the relationships between changes in BP and the catecholamines by ethnicity.

RESULTS

AA women (n=51; age=38.9+/-8.5 years) had smaller proportional BP changes from work to sleep and home to sleep than EA women (n=110; age=37.1+/-9.2 years). Overall, the work to sleep change in epinephrine excretion was positively associated with changes in both SBP (P<0.003) and DBP (P<0.001); however, there was an ethnic difference in the epinephrine-BP relationship. For AA women, these associations were highly positive and significant, but for EA women, there was little correlation. Nonetheless, the analysis also revealed that overall, the work to sleep BP changes were not directly related to ethnic differences in catecholamine variation.

CONCLUSION

The AA-EA difference in waking-sleep BP changes (dipping) is not directly related to ethnic differences in catecholamine variation; however, AA seem to have a greater BP sensitivity to epinephrine.

Ambulatory blood pressure monitoring: what a pediatrician should know

PURPOSE OF REVIEW

Ambulatory blood pressure monitoring is a useful tool for the evaluation and management of hypertension in children and adolescents. This review provides a basic overview of ambulatory blood pressure monitoring and summarizes the most recent available knowledge regarding its use in the pediatric population.

RECENT FINDINGS

Evaluation and validation of ambulatory blood pressure monitoring equipment in children remains limited, although advances in the interpretation of results for this age group have been reported specifically in the area of circadian (24 h) and ultradian (<24 h) variability. Blood pressure is a dynamic phenomenon that varies not only with time but also with changing patient and environmental circumstances. Growing evidence regarding conditions identified when this variability is considered, specifically white coat and masked hypertension, suggests that office blood pressure measurement may not be a sufficient screening test for hypertension-related target-organ damage.

SUMMARY

Information regarding ambulatory blood pressure monitoring use in children is increasing, although due to its limitations and expense, it remains a tool primarily utilized by the pediatric sub-specialist.

Chronic stress influences ambulatory blood pressure in adolescents

BACKGROUND

High ambulatory blood pressure (ABP) predicts cardiovascular events, even after controlling for clinic BP and other established risk factors.

PURPOSE

This study examined whether chronic or discrete stress in the past year was associated with greater ABP in adolescents.

METHOD

Participants were 217 male and female Black and White adolescents who wore ABP monitors on 2 consecutive school days and completed a survey of life events.

RESULTS

Report of discrete, negative events was not associated with ABP. Adolescents experiencing greater numbers of chronic, negative life events exhibited greater systolic blood pressure (SBP), independent of ethnicity; sex; body mass index; and location, position, physical activity, and consumption of food/caffeine/nicotine at time of measurement. Greater numbers of chronic, negative events were associated with greater diastolic blood pressure (DBP) among boys. When resting clinic BP was introduced into the model, the main effect of chronic, negative life events on ambulatory SBP became nonsignificant, whereas the effect of chronic, negative life events on male adolescents' DBP persisted.

CONCLUSIONS

Chronic stress is associated with greater ambulatory SBP among male and female adolescents and with greater ambulatory DBP among male adolescents. The latter association persisted after controlling for clinic BP, suggesting that males may be more vulnerable to chronic stress as a determinant of BP regulation than females early in life.