Evaluating different criteria for defining a complete ambulatory blood pressure monitoring recording: data from the Jackson Heart Study

Predictors of daytime blood pressure, nighttime blood pressure, and nocturnal dipping in patients with chronic kidney disease

Increasing attention has recently been paid to discrepancies between office and ambulatory blood pressure (BP) control in patients with chronic kidney disease (CKD), but information on mechanisms underlying circadian BP variations in CKD remains scarce. We described circadian BP patterns and their predictors in patients with CKD stages 1 to 5 referred for kidney function testing in a French tertiary hospital: 1122 ambulatory BP measurements from 635 participants. Factors associated with daytime and nighttime systolic BP (SBP) as well as with nocturnal SBP dipping (ratio of average nighttime to daytime SBP) were analyzed with linear mixed regression models. Participants (mean age 55 ± 16 years; 36% female, mean GFR 51 ± 22 mL/min/1.73m2) had a mean daytime and nighttime SBP of 130 ± 17 and 118 ± 18 mm Hg, respectively. The prevalence of impaired dipping (nighttime over daytime SBP ratio ≥ 0.9) increased from 32% in CKD stage 1 to 68% in CKD stages 4-5. After multivariable adjustment, measured GFR, diabetes, and sub-Saharan African origin were more strongly associated with nighttime than with daytime SBP, which led to significant associations with altered nocturnal BP dipping. For a 1 SD decrease in measured GFR, nighttime BP was 2.87 mmHg (95%CI, 1.44-4.30) higher and nocturnal SBP dipping ratio was 1.55% higher (95%CI, 0.85-2.26%). In conclusion, the prevalence of impaired nocturnal BP dipping increases substantially across the spectrum of CKD. Along with sub-Saharan African origin and diabetes, lower measured GFR was a robust and specific predictor of higher nighttime BP and blunted nocturnal BP decline.

Interplay of Race and Neighborhood Deprivation on Ambulatory Blood Pressure in Young Adults

Background

Ambulatory blood pressure (BP) monitoring measures nighttime BP and BP dipping, which are superior to in-clinic BP for predicting cardiovascular disease (CVD), the leading cause of death in America. Compared with other racial/ethnic groups, Black Americans exhibit elevated nighttime BP and attenuated BP dipping, including in young adulthood. Social determinants of health contribute to disparities in CVD risk, but the contribution of neighborhood deprivation on nighttime BP is unclear. Therefore, we examined associations between neighborhood deprivation with nighttime BP and BP dipping in young Black and White adults.

Methods

We recruited 21 Black and 26 White participants (20 M/27 F, mean age: 21 years, body mass index: 25±4 kg/m2) for 24-hour ambulatory BP monitoring. We assessed nighttime BP and BP dipping (nighttime:daytime BP ratio). The area deprivation index (ADI) was used to measure neighborhood deprivation. Associations between ADI and ambulatory BP were examined.

Results

Black participants exhibited higher nighttime diastolic BP compared with White participants (63±8 mmHg vs 58±7 mmHg, p=0.003), and attenuated BP dipping ratios for both systolic (0.92±0.06 vs 0.86±0.05, p=0.001) and diastolic BP (0.86±0.09 vs 0.78±0.08, p=0.007). Black participants experienced greater neighborhood deprivation compared with White participants (ADI scores: 110±8 vs 97±21, p<0.001), and ADI was associated with attenuated systolic BP dipping (ρ=0.342, p=0.019).

Conclusions

Our findings suggest neighborhood deprivation may contribute to higher nighttime BP and attenuated BP dipping, which are prognostic of CVD, and more prevalent in Black adults. Targeted interventions to mitigate the effects of neighborhood deprivation may help to improve nighttime BP.

Clinical Trial Registry

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04576338.

Nondipping blood pressure pattern predicts cardiovascular events and mortality in patients with atherosclerotic peripheral vascular disease

BACKGROUND

Patients with peripheral vascular disease (PVD) are often underdiagnosed and undertreated. Nocturnal nondipping blood pressure (BP) pattern, as diagnosed by ambulatory BP monitoring (ABPM), is associated with increased cardiovascular risk, but has not been studied in patients with PVD. We aimed to investigate if a nondipping BP pattern predicts cardiovascular events or all-cause death in outpatients with PVD.

METHODS

Consecutive outpatients with carotid or lower-extremity PVD were examined with 24-hour ABPM (n = 396). Nondipping was defined as a < 10% fall in systolic BP level during night-time. We used Cox regression models adjusting for potential confounders. We also evaluated the incremental prognostic value of dipping status in the COPART risk score. Our primary composite outcome was cardiovascular events or all-cause death.

RESULTS

In the cohort (mean age 70; 40% women), 137 events occurred during a 5.1-year median follow-up; incident rate of 7.35 events per 100 person-years. Nondipping was significantly associated with outcome (hazard ratio 1.55, 95% CI 1.07-2.26, p = 0.021) in a fully adjusted model. When adding nondipping to the risk markers in the COPART risk score, the model fit significantly improved (χ2 7.91, p < 0.005) and the C-statistic increased from 0.65 to 0.67.

CONCLUSION

In a cohort of outpatients with PVD, nondipping was an independent risk factor for future cardiovascular events or mortality and seemed to be a strong predictor in patients with carotid artery disease but not in lower-extremity PVD. Additional studies are needed to evaluate the clinical utility of ABPM for improved prevention in these high-risk patients. (ClinicalTrials.gov Identifier: NCT01452165).

Acceptability and Adherence to Home, Kiosk, and Clinic Blood Pressure Measurement Compared to 24-H Ambulatory Monitoring

BACKGROUND

The US Preventive Services Task Force recommends measuring blood pressure (BP) outside of clinic/office settings. While various options are available, including home devices, BP kiosks, and 24-h ambulatory BP monitoring (ABPM), understanding patient acceptability and adherence is a critical factor for implementation.

OBJECTIVE

To compare the acceptability and adherence of clinic, home, kiosk, and ABPM measurement.

DESIGN

Comparative diagnostic accuracy study which randomized adults to one of three BP measurement arms: clinic, home, and kiosk. ABPM was conducted on all participants.

PARTICIPANTS

Adults (18-85 years) receiving care at 12 Kaiser Permanente Washington primary care clinics (Washington State, USA) with a high BP (≥ 138 mmHg systolic or ≥ 88 mmHg diastolic) in the electronic health record with no hypertension diagnosis and on no hypertensive medications and with high BP at a research screening visit.

MEASURES

Patient acceptability was measured using a validated survey which was used to calculate an overall acceptability score (range 1-7) at baseline, after completing their assigned BP measurement intervention, and after completing ABPM. Adherence was defined based on the pre-specified number of BP measurements completed.

KEY RESULTS

Five hundred ten participants were randomized (mean age 59 years), with mean BP of 150/88. Overall acceptability score was highest (i.e. most acceptable) for Home BP (mean 6.2, SD 0.7) and lowest (least acceptable) for ABPM (mean 5.0, SD 1.0); scores were intermediate for Clinic (5.5, SD 1.1) and Kiosk (5.4, SD 1.0). Adherence was higher for Home (154/170, 90.6%) and Clinic (150/172, 87.2%) than for Kiosk (114/168, 67.9%)). The majority of participants (467/510, 91.6%) were adherent to ABPM.

CONCLUSIONS

Participants found home BP measurement most acceptable followed by clinic, BP kiosks, and ABPM. Our findings, coupled with recent evidence regarding the accuracy of home BP measurement, further support the routine use of home-based BP measurement in primary care practice in the US.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03130257 https://clinicaltrials.gov/ct2/show/NCT03130257.

Clinic, Home, and Kiosk Blood Pressure Measurements for Diagnosing Hypertension: a Randomized Diagnostic Study

BACKGROUND

The US Preventive Services Task Force recommends blood pressure (BP) measurements using 24-h ambulatory monitoring (ABPM) or home BP monitoring before making a new hypertension diagnosis.

OBJECTIVE

Compare clinic-, home-, and kiosk-based BP measurement to ABPM for diagnosing hypertension.

DESIGN, SETTING, AND PARTICIPANTS

Diagnostic study in 12 Washington State primary care centers, with participants aged 18-85 years without diagnosed hypertension or prescribed antihypertensive medications, with elevated BP in clinic.

INTERVENTIONS

Randomization into one of three diagnostic regimens: (1) clinic (usual care follow-up BPs); (2) home (duplicate BPs twice daily for 5 days); or (3) kiosk (triplicate BPs on 3 days). All participants completed ABPM at 3 weeks.

MAIN MEASURES

Primary outcome was difference between ABPM daytime and clinic, home, and kiosk mean systolic BP. Differences in diastolic BP, sensitivity, and specificity were secondary outcomes.

KEY RESULTS

Five hundred ten participants (mean age 58.7 years, 80.2% white) with 434 (85.1%) included in primary analyses. Compared to daytime ABPM, adjusted mean differences in systolic BP were clinic (-4.7mmHg [95% confidence interval -7.3, -2.2]; P<.001); home (-0.1mmHg [-1.6, 1.5];P=.92); and kiosk (9.5mmHg [7.5, 11.6];P<.001). Differences for diastolic BP were clinic (-7.2mmHg [-8.8, -5.5]; P<.001); home (-0.4mmHg [-1.4, 0.7];P=.52); and kiosk (5.0mmHg [3.8, 6.2]; P<.001). Sensitivities for clinic, home, and kiosk compared to ABPM were 31.1% (95% confidence interval, 22.9, 40.6), 82.2% (73.8, 88.4), and 96.0% (90.0, 98.5), and specificities 79.5% (64.0, 89.4), 53.3% (38.9, 67.2), and 28.2% (16.4, 44.1), respectively.

LIMITATIONS

Single health care organization and limited race/ethnicity representation.

CONCLUSIONS

Compared to ABPM, mean BP was significantly lower for clinic, significantly higher for kiosk, and without significant differences for home. Clinic BP measurements had low sensitivity for detecting hypertension. Findings support utility of home BP monitoring for making a new diagnosis of hypertension.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03130257 https://clinicaltrials.gov/ct2/show/NCT03130257.

Poorly controlled ambulatory blood pressure in outpatients with peripheral arterial disease

BACKGROUND

Patients with peripheral arterial disease (PAD) are generally less intensively managed than patients with coronary heart disease (CHD), despite that their risk of complications is believed to be equivalent. Identification of PAD patients at risk of poorly controlled blood pressure (BP) could lead to improved treatment, thus lowering the risk of cardiovascular (CV) complications. We aimed to describe the prevalence of poorly controlled cardiovascular (CV) risk factors, focusing on BP, in outpatients with PAD diagnosed in a vascular ultrasound laboratory.

METHODS

Consecutive outpatients with carotid and/or lower extremity PAD were included (n = 402) and examined with blood sampling, clinical BP, and 24-h ambulatory BP measurements. A poorly controlled clinical BP was defined as ≥140/90 mmHg, ambulatory BP ≥130/80 mmHg, low-density lipoprotein (LDL)-cholesterol level ≥2.5 mmol/L, and glycated hemoglobin (HbA1c) level >53 mmol/mol in those with diabetes.

RESULTS

Most of the patients had poorly controlled clinical (76.6%) and ambulatory BP (51.7%) profiles. Antihypertensive medications were prescribed in 84% of the patients. However, >40% of them used only 0-1 medication, and <25% of them used three or more agents. Clinical BP, a low number of medications, body mass index, and the presence of diabetes independently predicted a poorly controlled ambulatory BP. Nearly one-third of the patients were smokers, and most of the cohort had an LDL-cholesterol level of ≥2.5 mmol/L. An HbA1c level of >53 mmol/mol was present in 55% of diabetic patients.

CONCLUSION

Poorly controlled clinical and ambulatory systolic BP profiles were common. In addition, suboptimal control of other important CV risk factors was detected. The findings of this study highlight the need for better preventive efforts against CV risk factors in outpatients with PAD.

Objective short sleep duration and 24-hour blood pressure

BACKGROUND

Short sleep duration is a contributor to cardiovascular disease (CVD) events and mortality. Short sleep duration is associated with an increased risk of high clinic blood pressure (BP). BP measured outside the clinic using 24-h ambulatory blood pressure monitoring (ABPM) is a better predictor of an individual's CVD risk. We examined the association between objectively-assessed sleep duration and 24-h ambulatory blood pressure (ABP).

METHODS

A total of 893 working adults underwent sleep and ABPM. Participants were fitted with an ABPM device, and measures were taken at 28-30 min intervals. Objective sleep duration, and times of wakefulness and sleep during the 24-h ABPM period were derived from wrist-worn actigraphy. Linear regression, adjusted for age, sex, race/ethnicity, body mass index, smoking status, and diabetes were conducted on the relationship between sleep duration and the ABP measures.

RESULTS

Mean age of participants (final n = 729, 59.5% female, 11.9% Hispanic) was 45.2 ± 10.4 y. Mean actigraphy-derived sleep duration was 6.8 ± 1.2 h. Sleep duration <6 h was associated with a 1.73 mmHg higher 24-h systolic BP (p = 0.031) and 2.17 mmHg higher 24-h diastolic BP (p < 0.001). Shorter sleep duration was not associated with mean awake or asleep systolic BP (p = 0.89 and p = 0.92) or mean awake or asleep diastolic BP (p = 0.30 and p = 0.74).

CONCLUSIONS

To our knowledge, this is the largest study conducted which assessed sleep duration objectively while measuring 24-h ABP. Shorter sleep duration is associated with higher 24-h BP and potentially cardiovascular risk.

Using Predicted Atherosclerotic Cardiovascular Disease Risk for Discrimination of Awake or Nocturnal Hypertension

BACKGROUND

Several atherosclerotic cardiovascular disease (ASCVD) risk factors are associated with awake and nocturnal hypertension.

METHODS

We assessed the association between a composite ASCVD risk score and awake or nocturnal hypertension using data from participants aged 40-79 years who completed ambulatory blood pressure monitoring at the Year 30 Coronary Artery Risk Development in Young Adults study exam in 2015-2016 (n = 716) and the baseline Jackson Heart Study exam in 2000-2004 (n = 770). Ten-year predicted ASCVD risk was calculated using the Pooled Cohort risk equations. Awake hypertension was defined as mean awake systolic blood pressure (SBP) ≥135 mm Hg or diastolic blood pressure (DBP) ≥85 mm Hg and nocturnal hypertension was defined as mean asleep SBP ≥120 mm Hg or DBP ≥70 mm Hg.

RESULTS

Among participants with a 10-year predicted ASCVD risk <5%, 5% to <7.5%, 7.5% to <10%, and ≥10%, the prevalence of awake or nocturnal hypertension as a composite outcome was 29.5%, 47.8%, 62.2%, and 69.7%, respectively. After multivariable adjustment, higher ASCVD risk was associated with higher prevalence ratios for awake or nocturnal hypertension among participants with clinic-measured SBP/DBP <130/85 mm Hg but not ≥130/85 mm Hg. The C-statistic for discriminating between participants with vs. without awake or nocturnal hypertension was 0.012 (95% confidence interval 0.003, 0.016) higher when comparing a model with ASCVD risk and clinic-measured blood pressure (BP) together vs. clinic-measured BP without ASCVD risk.

CONCLUSIONS

Using 10-year predicted ASCVD risk in conjunction with clinic BP improves discrimination between individuals with and without awake or nocturnal hypertension.

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.

Association of Daytime and Nighttime Blood Pressure With Cardiovascular Disease Events Among African American Individuals

Importance

Little is known regarding health outcomes associated with higher blood pressure (BP) levels measured outside the clinic among African American individuals.

Objective

To examine whether daytime and nighttime BP levels measured outside the clinic among African American individuals are associated with cardiovascular disease (CVD) and all-cause mortality independent of BP levels measured inside the clinic.

Design, Setting, and Participants

This prospective cohort study analyzed data from 1034 African American participants in the Jackson Heart Study who completed ambulatory BP monitoring at baseline (September 26, 2000, to March 31, 2004). Mean daytime and nighttime BPs were calculated based on measurements taken while participants were awake and asleep, respectively. Data were analyzed from July 1, 2017, to April 30, 2019.

Main Outcomes and Measures

Cardiovascular disease events, including coronary heart disease and stroke, experienced through December 31, 2014, and all-cause mortality experienced through December 31, 2016, were adjudicated. The associations of daytime BP and nighttime BP, separately, with CVD events and all-cause mortality were determined using Cox proportional hazards regression models.

Results

A total of 1034 participants (mean [SD] age, 58.9 [10.9] years; 337 [32.6%] male; and 583 [56.4%] taking antihypertensive medication) were included in the study. The mean daytime systolic BP (SBP)/diastolic BP (DBP) was 129.4/77.6 mm Hg, and the mean nighttime SBP/DBP was 121.3/68.4 mm Hg. During follow-up (median [interquartile range], 12.5 [11.1-13.6] years for CVD and 14.8 [13.7-15.6] years for all-cause mortality), 113 CVD events and 194 deaths occurred. After multivariable adjustment, including in-clinic SBP and DBP, the hazard ratios (HRs) for CVD events for each SD higher level were 1.53 (95% CI, 1.24-1.88) for daytime SBP (per 13.5 mm Hg), 1.48 (95% CI, 1.22-1.80) for nighttime SBP (per 15.5 mm Hg), 1.25 (95% CI, 1.02-1.51) for daytime DBP (per 9.3 mm Hg), and 1.30 (95% CI, 1.06-1.59) for nighttime DBP (per 9.5 mm Hg). Nighttime SBP was associated with all-cause mortality (HR per 1-SD higher level, 1.24; 95% CI, 1.06-1.45), but no association was present for daytime SBP (HR, 1.13; 95% CI, 0.97-1.33) and daytime (HR, 0.95; 95% CI, 0.81-1.10) and nighttime (HR, 1.06; 95% CI, 0.90-1.24) DBP.

Conclusions and Relevance

Among African American individuals, higher daytime and nighttime SBPs were associated with an increased risk for CVD events and all-cause mortality independent of BP levels measured in the clinic. Measurement of daytime and nighttime BP using ambulatory monitoring during a 24-hour period may help identify African American individuals who have an increased cardiovascular disease risk.

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.

Masked hypertension and submaximal exercise blood pressure among adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC)

PURPOSE

Masked hypertension is associated with increased cardiovascular risk but is undetectable by clinic blood pressure (BP). Elevated systolic BP responses to submaximal exercise reveal the presence of masked hypertension in adults, but it is unknown whether this is the case during adolescence. We aimed to determine if exercise BP was raised in adolescents with masked hypertension, and its association with cardiovascular risk markers.

METHODS

A total of 657 adolescents (aged 17.7 ± 0.3 years; 41.9% male) from the Avon longitudinal study of parents and children (ALSPAC) completed a step-exercise test with pre-, post-, and recovery-exercise BP, clinic BP and 24-hour ambulatory BP. Masked hypertension was defined as clinic BP <140/90 mm Hg and 24-hour ambulatory BP ≥130/80 mm Hg. Assessment of left-ventricular (LV) mass index and carotid-femoral pulse wave velocity (aortic PWV) was also undertaken. Thresholds of clinic, pre-, post-, and recovery-exercise systolic BP were explored from ROC analysis to identify masked hypertension.

RESULTS

Fifty participants (7.8%) were classified with masked hypertension. Clinic, pre-, post-, and recovery-exercise systolic BP were associated with masked hypertension (AUC ≥ 0.69 for all, respectively), with the clinic systolic BP threshold of 115 mm Hg having high sensitivity and specificity and exercise BP thresholds of 126, 150, and 130 mm Hg, respectively, having high specificity and negative predictive value (individually or when combined) for ruling out the presence of masked hypertension. Additionally, this exercise systolic BP above the thresholds was associated with greater left-ventricular mass index and aortic PWV.

CONCLUSIONS

Submaximal exercise systolic BP is associated with masked hypertension and adverse cardiovascular structure in adolescents. Exercise BP may be useful in addition to clinic BP for screening of high BP and cardiovascular risk in adolescents.

Health Behaviors, Nocturnal Hypertension, and Non-dipping Blood Pressure: The Coronary Artery Risk Development in Young Adults and Jackson Heart Study

BACKGROUND

Several health behaviors have been associated with hypertension based on clinic blood pressure (BP). Data on the association of health behaviors with nocturnal hypertension and non-dipping systolic BP (SBP) are limited.

METHODS

We analyzed data for participants with ambulatory BP monitoring at the Year 30 Coronary Artery Risk Development in Young Adults (CARDIA) study exam in 2015-2016 (n = 781) and the baseline Jackson Heart Study (JHS) exam in 2000-2004 (n = 1,046). Health behaviors (i.e., body mass index, physical activity, smoking, and alcohol intake) were categorized as good, fair, and poor and assigned scores of 2, 1, and 0, respectively. A composite health behavior score was calculated as their sum and categorized as very good (score range = 6-8), good (5), fair (4), and poor (0-3). Nocturnal hypertension was defined as mean asleep SBP ≥ 120 mm Hg or mean asleep diastolic BP ≥ 70 mm Hg and non-dipping SBP as < 10% awake-to-asleep decline in SBP.

RESULTS

Among CARDIA study and JHS participants, 41.1% and 56.9% had nocturnal hypertension, respectively, and 32.4% and 72.8% had non-dipping SBP, respectively. The multivariable-adjusted prevalence ratios (95% confidence interval) for nocturnal hypertension associated with good, fair, and poor vs. very good health behavior scores were 1.03 (0.82-1.29), 0.98 (0.79-1.22), and 0.96 (0.77-1.20), respectively in CARDIA study and 0.98 (0.87-1.10), 0.96 (0.86-1.09), and 0.86 (0.74-1.00), respectively in JHS. The health behavior score was not associated non-dipping SBP in CARDIA study or JHS after multivariable adjustment.

CONCLUSIONS

A health behavior score was not associated with nocturnal hypertension or non-dipping SBP.

Blood pressure checks and diagnosing hypertension (BP-CHECK): Design and methods of a randomized controlled diagnostic study comparing clinic, home, kiosk, and 24-hour ambulatory BP monitoring

BACKGROUND

The US Preventive Services Task Force recommends out-of-office blood pressure (BPs) before making a new diagnosis of hypertension, using 24-h ambulatory (ABPM) or home BP monitoring (HBPM), however this is not common in routine clinical practice. Blood Pressure Checks and Diagnosing Hypertension (BP-CHECK) is a randomized controlled diagnostic study assessing the comparability and acceptability of clinic, home, and kiosk-based BP monitoring to ABPM for diagnosing hypertension. Stakeholders including patients, providers, policy makers, and researchers informed the study design and protocols.

METHODS

Adults aged 18-85 without diagnosed hypertension and on no hypertension medication with elevated BPs in clinic and at the baseline research visit are randomized to one of 3 regimens for diagnosing hypertension: (1) clinic BPs, (2) home BPs, or (3) kiosk BPs; all participants subsequently complete ABPM. The primary outcomes are the comparability (with daytime ABPM mean systolic and diastolic BP as the reference standard) and acceptability (e.g., adherence to, patient-reported outcomes) of each method compared to ABPM. Longer-term outcomes are assessed at 6-months including: patient-reported outcomes, primary care providers' diagnosis of hypertension; and BP control. We report challenges experienced and our response to these.

RESULTS

Enrollment began in May of 2017 with a target of randomizing 510 participants. BP thresholds for diagnosing hypertension in the US changed after the trial started. We discuss the stakeholder process used to assess and respond to these changes.

CONCLUSION AND PUBLIC HEALTH IMPACT

BP-CHECK will inform which hypertension diagnostic methods are most accurate, acceptable, and feasible to implement in primary care.

Masked hypertension and kidney function decline: the Jackson Heart Study

BACKGROUND

Hypertension diagnosed by blood pressure (BP) measured in the clinic is associated with rapid kidney function decline (RKFD) and incident chronic kidney disease (CKD). The extent to which hypertension defined using out-of-clinic BP measurements is associated with these outcomes is unclear.

METHODS

We evaluated the association of any masked hypertension (daytime SBP/DBP ≥ 135/85 mmHg, night-time SBP/DBP ≥ 120/70 mmHg or 24-h SBP/DBP ≥ 130/80 mmHg) with RKFD and incident CKD among 676 African-Americans in the Jackson Heart Study with clinic-measured SBP/DBP less than 140/90 mmHg who completed ambulatory BP monitoring in 2000-2004. RKFD was defined as a decline in estimated glomerular filtration rate (eGFR) at least 30% and incident CKD was defined as development of eGFR less than 60 ml/min per 1.73 m with an at least 25% decline in eGFR between 2000-2004 and 2009-2013.

RESULTS

The mean age of participants was 57.6 years, 28.8% were men and 52.7% had any masked hypertension. After a median follow-up of 8 years, 13.8 and 8.6% of participants had RKFD and incident CKD, respectively. In unadjusted analyses, masked hypertension was associated with an increased odds for incident CKD [odds ratio (OR) 2.20, 95% confidence interval (CI) 1.22, 3.97]. This association remained statistically significant after adjustment for demographic characteristics, baseline eGFR and albumin-to-creatinine ratio (OR 1.95, 95% CI 1.04, 3.67) but was eliminated after propensity score adjustment (OR 1.62, 95% CI 0.87, 3.00). There was no association between masked hypertension and RKFD.

CONCLUSION

Masked hypertension may be associated with the development of CKD in African-Americans.

Evidence-based proposal for the number of ambulatory readings required for assessing blood pressure level in research settings: an analysis of the IDACO database

BACKGROUND

Guidelines on the required number of ambulatory blood pressure (ABP) readings focus on individual patients. Clinical researchers often face the dilemma of applying recommendations and discarding potentially valuable information or accepting fewer readings.

METHODS

Starting from ABP recordings with ≥30/≥10 awake/asleep readings in 4277 participants enrolled in eight population studies in the International Database on Ambulatory Blood Pressure in Relation to Cardiovascular Outcomes (IDACO), we randomly selected a certain number of readings (from 30 to 1 awake and 10 to 1 asleep readings) at a time over 1000 bootstraps at each step. We evaluated: (i) concordance of the ABP level; (ii) consistency of the cross-classification based on office blood pressure and ABP; and (iii) accuracy in predicting cardiovascular complications. For each criterion, we fitted a regression line joining data points relating outcome to the number of readings covering the ranges of 30-20/10-7 for awake/asleep readings.

RESULTS

Reducing readings widened the SD of the systolic/diastolic differences between full (reference) and selected recordings from 1.7/1.2 (30 readings) to 14.3/10.3 mm Hg (single reading) during wakefulness, and from 1.9/1.4 to 10.3/7.7 mm Hg during sleep; lowered the κ statistic from 0.94 to 0.63, and decreased the hazard ratio associated with 10/5 mm Hg increments in systolic/diastolic ABP from 1.21/1.14 to 1.06/1.04 during wakefulness and from 1.26/1.17 to 1.14/1.08 during sleep. The first data points falling off these regression lines during wakefulness/sleep corresponded to 8/3 and 8/4 readings for criteria (i) and (iii) and to 5 awake readings for criterion (ii).

CONCLUSIONS

24-h ambulatory recordings with ≥8/≥4 awake/asleep readings yielded ABP levels similar to recordings including the guideline-recommended ≥20/≥7 readings. These criteria save valuable data in a research setting, but are not applicable to clinical practice.