Race and sex differences in asleep blood pressure: The Coronary Artery Risk Development in Young Adults (CARDIA) study

Device-estimated sleep metrics do not mediate the relation between race and blood pressure dipping in young black and white women

Short, disturbed, and irregular sleep may contribute to blunted nocturnal blood pressure (BP) dipping, a predictor of cardiovascular disease. Black women (BLW) demonstrate less BP dipping and poorer sleep health than White women (WHW). However, it remains unclear whether device-estimated sleep health metrics mediate the relation between race and BP dipping in young women. We hypothesized that the relation between race and BP dipping would be partly mediated by sleep health metrics of sleep duration, sleep efficiency, and sleep regularity. Participants (20 BLW, 17 WHW) were 18-29 years old, normotensive, nonobese, and without evidence of sleep disorders. Systolic and diastolic BP dipping were derived from 24-h ambulatory BP monitoring. Habitual sleep duration and sleep efficiency were estimated via 14 days of wrist actigraphy. Sleep duration regularity was calculated as the standard deviation (SD) of nightly sleep duration (SDSD). Sleep timing regularity metrics were calculated as the SD of sleep onset and sleep midpoint (SMSD). Mediation analysis tested the mediating effect of each sleep metric on the relation between race and BP dipping. BLW experienced less systolic (P = .02) and diastolic (P = .01) BP dipping. Sleep duration (P = .14) was not different between groups. BLW had lower sleep efficiency (P < .01) and higher SDSD (P = .02), sleep onset SD (P < .01) and SMSD (P = .01). No sleep metrics mediated the relation between race and BP dipping (all indirect effects P > .38). In conclusion, mediation pathways of sleep health metrics do not explain racial differences in nocturnal BP dipping between young BLW and WHW.

While You Are Sleeping: Marital Ambivalence and Blunted Nocturnal Blood Pressure

Marital relationships offer health benefits, including a lower risk of cardiovascular disease (CVD). However, quality of the relationship matters; ambivalent behaviors may increase CVD risk by affecting blunted nocturnal blood pressure (BP) dipping. This study tracked daytime and nocturnal SBP and DBP in 180 normotensive individuals (90 couples; participant mean age 25.04; 91.58% white) over a 24 h period using ambulatory blood pressure monitors to explore the impact of martial quality. Results showed that perceptions of spousal ambivalence were associated with blunted nocturnal BP dipping. Perceptions of one's own behavior as ambivalent also showed blunted nocturnal dipping. When in an ambivalent relationship, a gender interaction was found such that women were most likely to have blunted SBP dipping, but men were more likely to have blunted nocturnal DBP dipping. Overall, this study found an association between ambivalence and BP dipping, thus uncovering one virtually unexplored pathway by which marital relationships may have adverse effects on health.

Non-dipping blood pressure pattern is associated with cardiovascular events in a 21-year follow-up study

Non-dipping blood pressure (BP) pattern is a predictor for cardiovascular (CV) events and mortality. We evaluated dipping status change and its association with incidence of non-fatal CV events in middle-aged subjects. The OPERA study was carried out during the years 1991-1993, with a follow-up study 21.7 years later. In this study, we included 452 participants with 24-h ambulatory BP measurements (ABPM) available in both surveys. The study population was divided into four groups according to the dipping pattern change: dipping-dipping (n = 152/33.6%), dipping-non-dipping (n = 198/43.8%), non-dipping-dipping (n = 20/4.4%), and non-dipping-non-dipping (n = 82/18.1%). Sixty-five participants experienced a CV event (14.4%) during the 21.7 (SD 0.8) years of follow-up. The incidence of events was highest (28%) in the non-dipping-non-dipping group, and lowest (6.6%) in the dipping-dipping group (p < 0.001). In Cox regression analyses the covariates were age, sex, total cholesterol, hypertension and use of antihypertensive medication, systolic office BP and ambulatory mean or nighttime systolic BP, as well as the change in the variables during the follow-up period. After adjustments, the association of the non-dipping-non-dipping pattern with CV events compared with the dipping-dipping pattern remained significant (HR 4.01; 95% CI 1.89-8.67, p < 0.001). In summary, non-dipping-non-dipping pattern was associated with non-fatal CV events in the long term, and the effect was independent of the conventional risk factors including office and ambulatory BP levels.

Race differences in ambulatory blood pressure monitoring parameters

BACKGROUND

Mean systolic and diastolic blood pressure (SBP and DBP) on ambulatory blood pressure (BP) monitoring (ABPM) are higher among Black compared with White adults. With 48 to 72 BP measurements obtained over 24 h, ABPM can generate parameters other than mean BP that are associated with increased risk for cardiovascular events. There are few data on race differences in ABPM parameters other than mean BP.

METHODS

To estimate differences between White and Black participants in ABPM parameters, we used pooled data from five US-based studies in which participants completed ABPM (n = 2580). We calculated measures of SBP and DBP level, including mean, load, peak, and measures of SBP and DBP variability, including average real variability (ARV) and peak increase.

RESULTS

There were 1513 (58.6%) Black and 1067 (41.4%) White participants with mean ages of 56.1 and 49.0 years, respectively. After multivariable adjustment, asleep SBP and DBP load were 5.7% (95% CI: 3.5-7.9%) and 2.7% (95% CI: 1.1-4.3%) higher, respectively, among Black compared with White participants. Black compared with White participants also had higher awake DBP ARV (0.3 [95%CI: 0.0-0.6] mmHg) and peak increase in DBP (0.4 [95% CI: 0.0-0.8] mmHg). There was no evidence of Black:White differences in awake measures of SBP level, asleep peak SBP or DBP, awake and asleep measures of SBP variability or asleep measures of DBP variability after multivariable adjustment.

CONCLUSION

Asleep SBP load, awake DBP ARV and peak increase in awake DBP were higher in Black compared to White participants, independent of mean BP on ABPM.

Non-Dipping Blood Pressure or Nocturnal Hypertension: Does One Matter More?

PURPOSE OF REVIEW

Nocturnal hypertension and non-dipping are both associated with increased cardiovascular risk; however, debate remains over which is a better prognosticator of cardiovascular outcomes. This review explores current literature on nocturnal hypertension and non-dipping to assess their relationship to cardiovascular disease and implications for clinical practice.

RECENT FINDINGS

While current data remain inconclusive, some suggest that nocturnal hypertension is a more reliable and clinically significant marker of cardiovascular risk than non-dipping status. Importantly, reducing nocturnal HTN and non-dipping through chronotherapy, specifically evening dosing of antihypertensives, has not been conclusively shown to provide long-term cardiovascular benefits. Recent data suggests that non-dipping, compared to nocturnal hypertension, may be falling out of favor as a prognostic indicator for adverse cardiovascular outcomes. However, additional information is needed to understand how aberrant nighttime blood pressure patterns modulate cardiovascular risk to guide clinical management.

Reproducibility and diurnal variation in middle cerebral artery blood velocity in healthy humans

NEW FINDINGS

What is the central question of this study? We sought to establish between-day reproducibility in estimates of middle cerebral artery blood velocity (MCAv) and cerebrovascular reactivity (CVR) in young, healthy male and female adults in tightly controlled experimental conditions. What is the main finding and its importance? Measures of MCAv assessed during morning, afternoon and evening hours are reproducible between days. There is diurnal variation in CVR, with values being highest during the evening compared with the morning. Greater diurnal variation in CVR is associated with more efficient sleep and greater nocturnal blood pressure dipping. These data enhance our understanding of modulators of MCAv and CVR.

ABSTRACT

Transcranial Doppler (TCD) is used to assess cerebral blood velocity (CBV) and cerebrovascular reactivity (CVR). Assessments of TCD reproducibility are limited, and few include multiple within-day measurements. We sought to establish reproducibility of CBV and CVR in healthy adults during three time periods (morning, afternoon and evening). We hypothesized that CBV and CVR measured at the same time of day are reproducible between days. We also hypothesized that CBV and CVR exhibit diurnal variation, with measurements being higher in the evening compared with morning/afternoon hours. Twelve adults [six male and six female, 27 years (95% CI, 22-31 years)] completed three measurements (morning, afternoon and evening) on two separate days in controlled conditions (e.g., meals, activity and sleep). Middle cerebral artery blood velocity (MCAv, TCD) was measured continuously at rest and during two CVR tests (end-expiratory apnoea and carbogen inhalation). Intraclass correlation coefficients for resting MCAv showed moderate to good reproducibility, which did not differ between morning, afternoon and evening (0.87, 0.56 and 0.67, respectively; P > 0.05). Intraclass correlation coefficients for peak MCAv during apnoea (0.80, 0.46 and 0.65, respectively; P > 0.05) and minute 2 of carbogen inhalation (0.81, 0.74 and 0.73, respectively; P > 0.05) were also not different from morning compared with afternoon/evening. Time of day had no effect on resting MCAv (F = 0.69, P = 0.51, ƞp 2  = 0.06) or the peak response to apnoea (F = 1.00, P = 0.39, ƞp 2  = 0.08); however, peak MCAv during carbogen breathing exhibited diurnal variation, with highest values in the evening (F = 3.41, P = 0.05, ƞp 2  = 0.24). Measures of CBV and CVR assessed via TCD during morning, afternoon and evening hours are reproducible between days. There is diurnal variation in the MCAv response to carbogen exposure, with CVR being highest during evening compared with morning hours.

Toward Precision Medicine: Circadian Rhythm of Blood Pressure and Chronotherapy for Hypertension - 2021 NHLBI Workshop Report

Healthy individuals exhibit blood pressure variation over a 24-hour period with higher blood pressure during wakefulness and lower blood pressure during sleep. Loss or disruption of the blood pressure circadian rhythm has been linked to adverse health outcomes, for example, cardiovascular disease, dementia, and chronic kidney disease. However, the current diagnostic and therapeutic approaches lack sufficient attention to the circadian rhythmicity of blood pressure. Sleep patterns, hormone release, eating habits, digestion, body temperature, renal and cardiovascular function, and other important host functions as well as gut microbiota exhibit circadian rhythms, and influence circadian rhythms of blood pressure. Potential benefits of nonpharmacologic interventions such as meal timing, and pharmacologic chronotherapeutic interventions, such as the bedtime administration of antihypertensive medications, have recently been suggested in some studies. However, the mechanisms underlying circadian rhythm-mediated blood pressure regulation and the efficacy of chronotherapy in hypertension remain unclear. This review summarizes the results of the National Heart, Lung, and Blood Institute workshop convened on October 27 to 29, 2021 to assess knowledge gaps and research opportunities in the study of circadian rhythm of blood pressure and chronotherapy for hypertension.

Diagnosing hypertension in primary care: a retrospective cohort study to investigate the importance of night-time blood pressure assessment

BACKGROUND

Ambulatory blood-pressure monitoring (ABPM) has become less frequent in primary care since the COVID-19 pandemic, with home blood-pressure monitoring (HBPM) often the preferred alternative; however, HBPM cannot measure night-time blood pressure (BP), and patients whose night-time BP does not dip, or rises (reverse dipping), have poorer cardiovascular outcomes.

AIM

To investigate the importance of measuring night-time BP when assessing individuals for hypertension.

DESIGN AND SETTING

Retrospective cohort study of two patient populations - namely, hospital patients admitted to four UK acute hospitals located in Oxfordshire, and participants of the BP in different ethnic groups (BP-Eth) study, who were recruited from 28 UK general practices in the West Midlands.

METHOD

Using BP data collected for the two cohorts, three systolic BP phenotypes (dipper, non-dipper, and reverse dipper) were studied.

RESULTS

Among the hospital cohort, 48.9% (n = 10 610/21 716) patients were 'reverse dippers', with an average day-night systolic BP difference of +8.0 mmHg. Among the community (BP-Eth) cohort, 10.8% (n = 63/585) of patients were reverse dippers, with an average day-night systolic BP difference of +8.5 mmHg. Non-dipper and reverse-dipper phenotypes both had lower daytime systolic BP and higher night-time systolic BP than the dipper phenotype. Average daytime systolic BP was lowest in the reverse-dipping phenotype (this was 6.5 mmHg and 6.8 mmHg lower than for the dipper phenotype in the hospital and community cohorts, respectively), thereby placing them at risk of undiagnosed, or masked, hypertension.

CONCLUSION

Not measuring night-time BP puts all groups, other than dippers, at risk of failure to identify hypertension. As a result of this study, it is recommended that GPs should offer ABPM to all patients aged ≥60 years as a minimum when assessing for hypertension.

Vascular health and diffusion properties of normal appearing white matter in midlife

In this study, we perform a region of interest diffusion tensor imaging and advanced diffusion complexity analysis of normal appearing white matter to determine the impact of vascular health on these diffusivity metrics in midlife adults. 77 participants (26 black, 35 female) at year 30 visit in the Coronary Artery Risk Development in Young Adults longitudinal study were scanned with an advanced diffusion-weighted imaging and fluid-attenuated inversion recovery protocol. Fractional anisotropy and non-linear diffusion complexity measures were estimated. Cumulative measures across 30 years (9 study visits) of systolic blood pressure, body mass index, glucose, smoking and cholesterol were calculated as the area under the curve from baseline up to year 30 examination. Partial correlation analyses assessed the association between cumulative vascular health measures and normal appearing white matter diffusion metrics in these participants. Midlife normal appearing white matter diffusion properties were significantly associated (P < 0.05) with cumulative exposure to vascular risk factors from young adulthood over the 30-year time period. Higher cumulative systolic blood pressure exposure was associated with increased complexity and decreased fractional anisotropy. Higher cumulative body mass index exposure was associated with decreased fractional anisotropy. Additionally, in the normal appearing white matter of black participants (P < 0.05), who exhibited a higher cumulative vascular risk exposure, fractional anisotropy was lower and complexity was higher in comparison to normal appearing white matter in white participants. Higher burden of vascular risk factor exposure from young adulthood to midlife is associated with changes in the diffusion properties of normal appearing white matter in midlife. These changes which may reflect axonal disruption, increased inflammation and/or increased glial proliferation, were primarily observed in both anterior and posterior normal appearing white matter regions of the corpus callosum. These results suggest that microstructural changes in normal appearing white matter are sensitive to vascular health during young adulthood and are possibly therapeutic targets in interventions focused on preserving white matter health across life.

Effects of Experimental Sleep Restriction on Ambulatory and Sleep Blood Pressure in Healthy Young Adults: A Randomized Crossover Study

[Figure: see text].

Chronotherapy for morning blood pressure surge in hypertensive patients: a systematic review and meta-analysis

BACKGROUND

The morning blood pressure surge (MBPS) is related to an exaggerated risk of cardiovascular diseases and mortality. With increasing attention on circadian change in blood pressure and extensive use of ambulatory blood pressure monitoring (ABPM), chronotherapy that administration of medication according to biological rhythm, is reported to improve cardiovascular outcomes. The aim of this study is to evaluate the influence of chronotherapy of antihypertensive drugs upon MBPS in hypertensive patients.

METHODS

A search strategy was applied in Ovid MEDLINE, EMBASE, Cochrane (Wiley) CENTRAL Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the Chinese Biomedical literature database. No language and date restrictions. Randomized controlled trials (RCT) assessing the efficacy of evening and morning administration of the same medications in adult patients with primary hypertension were included.

RESULTS

A total of ten trials, comprising 1724 participants with a mean age of 61 and 51% female, were included in this study. Combined analysis observed significant reduction of MBPS (- 5.30 mmHg, 95% CI - 8.80 to - 1.80), night-time SBP (- 2.29 mmHg, 95% CI - 4.43 to - 0.15), night-time DBP (- 1.63 mmHg, 95 %CI - 3.23 to - 0.04) and increase in night blood pressure dipping (3.23%, 95% CI 5.37 to 1.10) in evening dosage compared with traditional morning dosage of blood pressure-lowering drugs. No significant difference was found in the incidence of overall adverse effects (RR 0.65, 95% CI 0.30 to 1.41) and withdrawal due to adverse effects (RR 0.95, 95% CI 0.53 to 1.71).

CONCLUSIONS

Our study suggested that evening administration of antihypertensive medications exerted better blood pressure-lowering effect on MBPS compared with conventional morning dosage. Safety assessment also indicated that the evening regimen did not increase the risk of adverse events. However, endpoint studies need to be carried out to confirm the significance and feasibility of this treatment regimen in clinical practice.

Association Between Ambulatory Blood Pressure and Coronary Artery Calcification: The JHS

[Figure: see text].

Twenty-Five-Year Changes in Office and Ambulatory Blood Pressure: Results From the Coronary Artery Risk Development in Young Adults (CARDIA) Study

BACKGROUND

Blood pressure (BP) measured in the office setting increases from early through later adulthood. However, it is unknown to what extent out-of-office BP derived via ambulatory BP monitoring (ABPM) increases over time, and which participant characteristics and risk factors might contribute to these increases.

METHODS

We assessed 25-year change in office- and ABPM-derived BP across sex, race, diabetes mellitus (DM), and body mass index (BMI) subgroups in the Coronary Artery Risk Development in Young Adults study using multivariable-adjusted linear mixed effects models.

RESULTS

We included 288 participants who underwent ABPM at the Year 5 Exam (mean [SD] age, 25.1 [3.7]; 45.8% men) and 455 participants who underwent ABPM at the Year 30 Exam (mean [SD] age, 49.5 [3.7]; 42.0% men). Office, daytime, and nighttime systolic BP (SBP) increased 12.8 (95% confidence interval [CI], 7.6-17.9), 14.7 (95% CI, 9.7-19.8), and 16.6 (95% CI, 11.4-21.8) mm Hg, respectively, over 25 years. Office SBP increased 6.5 (95% CI, 2.3-10.6) mm Hg more among black compared with white participants. Daytime SBP increased 6.3 (95% CI, 0.2-12.4) mm Hg more among participants with a BMI ≥25 vs. <25 kg/m2. Nighttime SBP increased 4.7 (95% CI, 0.5-8.9) mm Hg more among black compared with white participants, and 17.3 (95% CI, 7.2-27.4) mm Hg more among participants with vs. without DM.

CONCLUSIONS

Office- and ABPM-derived BP increased more from early through middle adulthood among black adults and participants with DM and BMI ≥25 kg/m2.

Association of Obstructive Sleep Apnea With Nighttime Blood Pressure in African Americans: The Jackson Heart Study

BACKGROUND

Obstructive sleep apnea (OSA), nocturnal hypertension, and nondipping systolic blood pressure (BP) are each highly prevalent among African Americans. However, few data are available on the association between OSA and nighttime BP in this population.

METHODS

We examined the association of OSA with nighttime BP among African Americans who completed 24-hour ambulatory BP monitoring (ABPM) at Exam 1 (2000-2004) of the Jackson Heart Study (JHS) and subsequently participated in the JHS Sleep Study (2012-2016). Type 3 home sleep apnea testing was used to assess OSA measures, including respiratory event index (REI4%) and percent sleep time <90% oxygen saturation (nocturnal hypoxemia). Nocturnal hypertension was defined as mean asleep systolic BP (SBP) ≥120 mm Hg or diastolic BP (DBP) ≥70 mm Hg. Multivariable linear regression models were fit to estimate the association between each OSA measure and nighttime SBP and DBP.

RESULTS

Among 206 participants who completed ABPM and participated in the Jackson Heart Sleep Study, 50.5% had nocturnal hypertension and 26.2% had moderate to severe OSA (REI4% ≥15 events/hour). After multivariable adjustment, each SD (13.3 events/hour) increase in REI4% was associated with 1.75 mm Hg higher nighttime DBP (95% confidence interval (CI): 0.38, 3.11) and a prevalence ratio of 1.11 (95% CI: 1.00, 1.24) for nocturnal hypertension. Each SD (10.4%) increase in nocturnal hypoxemia was associated with a 1.91 mm Hg higher nighttime SBP (95% CI: 0.15, 3.66).

CONCLUSIONS

Severity of OSA and nocturnal hypoxemia were associated with high nighttime BP in African American participants in the JHS.

Associations Between Objective Sleep and Ambulatory Blood Pressure in a Community Sample

OBJECTIVE

Epidemiologic data increasingly support sleep as a determinant of cardiovascular disease risk. Fewer studies have investigated the mechanisms underlying this relationship using objective sleep assessment approaches. Therefore, the aim of this study was to examine associations between daily blood pressure (BP) and both objectively assessed sleep duration and efficiency.

METHODS

A diverse community sample of 300 men and women aged 21 to 70 years, enrolled in the North Texas Heart Study, participated in the study. Actigraphy-assessed sleep was monitored for two consecutive nights with ambulatory BP sampled randomly within 45-minute blocks on the first and second day as well as the second night.

RESULTS

Overall, sleep duration results paralleled those of sleep efficiency. Individuals with lower sleep efficiency had higher daytime systolic (B = -0.35, SE = 0.11, p = .0018, R = 0.26) but not diastolic BP (B = -0.043, SE = 0.068, p = .52, R = 0.17) and higher nighttime BP (systolic: B = -0.37, SE = 0.10, p < .001, R = .15; diastolic: B = -0.20, SE = 0.059, p < .001, R = .14). Moreover, lower sleep efficiency on one night was associated with higher systolic (B = -0.51, SE = 0.11, p < .001, R = 0.23) and diastolic BP (B = -0.17, SE = 0.065, p = .012, R = .16) the following day. When 'asleep' BP was taken into account instead of nighttime BP, the associations between sleep and BP disappeared. When both sleep duration and efficiency were assessed together, sleep efficiency was associated with daytime systolic BP, whereas sleep duration was associated with nighttime BP.

CONCLUSIONS

Lower sleep duration and efficiency are associated with higher daytime systolic BP and higher nighttime BP when assessed separately. When assessed together, sleep duration and efficiency diverge in their associations with BP at different times of day. These results warrant further investigation of these possible pathways to disease.

Association of Sleep Characteristics With Nocturnal Hypertension and Nondipping Blood Pressure in the CARDIA Study

Background Sleep characteristics and disorders are associated with higher blood pressure (BP) when measured in the clinic setting. Methods and Results We tested whether self-reported sleep characteristics and likelihood of obstructive sleep apnea (OSA) were associated with nocturnal hypertension and nondipping systolic BP (SBP) among participants in the CARDIA (Coronary Artery Risk Development in Young Adults) study who completed 24-hour ambulatory BP monitoring during the year 30 examination. Likelihood of OSA was determined using the STOP-Bang questionnaire. Global sleep quality, habitual sleep duration, sleep efficiency, and midsleep time were obtained from the Pittsburgh Sleep Quality Index. Nocturnal hypertension was defined as mean asleep SBP ≥120 mm Hg or diastolic BP ≥70 mm Hg. Nondipping SBP was defined as a decline in awake-to-asleep SBP <10%. Among 702 participants, the prevalence of nocturnal hypertension and nondipping SBP was 41.3% and 32.5%, respectively. After multivariable adjustment including cardiovascular risk factors, the prevalence ratios (PRs) for nocturnal hypertension and nondipping SBP associated with high versus low likelihood of OSA were 1.32 (95% CI, 1.00-1.75) and 1.31 (95% CI, 1.02-1.68), respectively. The association between likelihood of OSA and nocturnal hypertension was stronger for white participants (PR: 2.09; 95% CI, 1.23-3.48) compared with black participants (PR: 1.11; 95% CI, 0.79-1.56). The PR for nondipping SBP associated with a 1-hour later midsleep time was 0.92 (95% CI, 0.85-0.99). Global sleep quality, habitual sleep duration, and sleep efficiency were not associated with either nocturnal hypertension or nondipping SBP. Conclusions These findings suggest that addressing OSA risk and sleep timing in a clinical trial may improve BP during sleep.

Morning Blood Pressure Surge and Cardiovascular Disease Events and All-Cause Mortality in Blacks: The Jackson Heart Study

The cardiovascular disease (CVD) and mortality risk associated with morning blood pressure (BP) surge and its components among black adults, a population with high BP during the asleep period, is unknown. We studied Jackson Heart Study participants who completed 24-hour ambulatory BP monitoring at the baseline exam in 2000 to 2004 (n=761). The sleep-trough morning surge was calculated as the mean 2-hour postawakening systolic BP (SBP) minus the lowest nighttime SBP, preawakening morning surge as mean 2-hour postawakening SBP minus mean 2-hour preawakening SBP, and rising morning surge as the first postawakening SBP minus the last preawakening SBP. The primary outcome was the occurrence of CVD events including the composite of coronary heart disease or stroke. Over a median follow-up of 14.0 years, there were 74 CVD (coronary heart disease or stroke) events and 144 deaths. Higher tertiles of sleep-trough, preawakening, and rising SBP surge were not associated with CVD risk after multivariable adjustment. In contrast, the highest tertile of the individual components of morning surge, including postawakening SBP (tertiles 2 and 3 versus 1: hazard ratio [95% CI]: 1.58 [0.71-3.53] and 4.04 [1.91-8.52], respectively), lowest nighttime SBP (1.29 [0.59-2.84] and 2.87 [1.41-5.83]), preawakening SBP (1.26 [0.57-2.80] and 2.79 [1.32-5.93]), first postawakening SBP (1.60 [0.73-3.51] and 2.93 [1.40-6.16]), and last preawakening SBP (1.23 [0.57-2.68] and 2.99 [1.46-6.12]), was associated with increased CVD risk after multivariable adjustment. Among black adults, the components of morning SBP surge, but not morning SBP surge itself, were associated with increased CVD risk.

Development of Predictive Equations for Nocturnal Hypertension and Nondipping Systolic Blood Pressure

Background Nocturnal hypertension, defined by a mean asleep systolic blood pressure (SBP)/diastolic blood pressure (BP) ≥120/70 mm Hg, and nondipping SBP, defined by an awake-to-asleep decline in SBP <10%, are each associated with increased risk for cardiovascular disease. Methods and Results We developed predictive equations to identify adults with a high probability of having nocturnal hypertension or nondipping SBP using data from the CARDIA (Coronary Artery Risk Development in Young Adults) study (n=787), JHS (Jackson Heart Study) (n=1063), IDH (Improving the Detection of Hypertension) study (n=395), and MHT (Masked Hypertension) study (n=772) who underwent 24-hour ambulatory BP monitoring. Participants were randomized to derivation (n=2511) or validation (n=506) data sets. The prevalence rates of nocturnal hypertension and nondipping SBP were 39.7% and 44.9% in the derivation data set, respectively, and 36.6% and 44.5% in the validation data set, respectively. The predictive equation for nocturnal hypertension included age, race/ethnicity, smoking status, neck circumference, height, high-density lipoprotein cholesterol, albumin/creatinine ratio, and clinic SBP and diastolic BP. The predictive equation for nondipping SBP included age, sex, race/ethnicity, waist circumference, height, alcohol use, high-density lipoprotein cholesterol, and albumin/creatinine ratio. Concordance statistics (95% CI) for nocturnal hypertension and nondipping SBP predictive equations in the validation data set were 0.84 (0.80-0.87) and 0.73 (0.69-0.78), respectively. Compared with reference models including antihypertensive medication use and clinic SBP and diastolic BP as predictors, the continuous net reclassification improvement (95% CI) values for the nocturnal hypertension and nondipping SBP predictive equations were 0.52 (0.35-0.69) and 0.51 (0.34-0.69), respectively. Conclusions These predictive equations can direct ambulatory BP monitoring toward adults with high probability of having nocturnal hypertension and nondipping SBP.