Masked Hypertension and Cardiovascular Disease Events in a Prospective Cohort of Blacks: The Jackson Heart Study.
ABSTRACT: Masked hypertension, defined as nonelevated clinic blood pressure (BP) with elevated out-of-clinic BP, has been associated with increased cardiovascular disease (CVD) risk in Europeans and Asians. Few data are available on masked hypertension and CVD and mortality risk among blacks. We analyzed data from the Jackson Heart Study, a prospective cohort study of blacks. Analyses included participants with clinic-measured systolic/diastolic BP <140/90 mm?Hg who completed ambulatory BP monitoring after the baseline examination in 2000 to 2004 (n=738). Masked daytime (10:00 am-8:00 pm) hypertension was defined as mean ambulatory systolic/diastolic BP ?135/85 mm?Hg. Masked nighttime (midnight to 6:00 am) hypertension was defined as mean ambulatory systolic/diastolic BP ?120/70 mm?Hg. Masked 24-hour hypertension was defined as mean systolic/diastolic BP ?130/80 mm?Hg. CVD events (nonfatal/fatal stroke, nonfatal myocardial infarction, or fatal coronary heart disease) and deaths identified through December 2010 were adjudicated. Any masked hypertension (masked daytime, nighttime, or 24-hour hypertension) was present in 52.2% of participants; 28.2%, 48.2% and 31.7% had masked daytime, nighttime, and 24-hour hypertension, respectively. There were 51 CVD events and 44 deaths during a median follow-up of 8.2 and 8.5 years, respectively. CVD rates per 1000 person-years (95% confidence interval) in participants with and without any masked hypertension were 13.5 (9.9-18.4) and 3.9 (2.2-7.1), respectively. The multivariable adjusted hazard ratio (95% confidence interval) for CVD was 2.49 (1.26-4.93) for any masked hypertension and 2.86 (1.59-5.13), 2.35 (1.23-4.50), and 2.52 (1.39-4.58) for masked daytime, nighttime, and 24-hour hypertension, respectively. Masked hypertension was not associated with all-cause mortality. Masked hypertension is common and associated with increased risk for CVD events in blacks.
Project description:BACKGROUND:Ambulatory blood pressure (BP) monitoring is the reference standard for out-of-clinic BP measurement. Thresholds for identifying ambulatory hypertension (daytime systolic BP [SBP]/diastolic BP [DBP] ?135/85 mm?Hg, 24-hour SBP/DBP ?130/80 mm?Hg, and nighttime SBP/DBP ?120/70 mm?Hg) have been derived from European, Asian, and South American populations. We determined BP thresholds for ambulatory hypertension in a US population-based sample of African American adults. METHODS:We analyzed data from the Jackson Heart Study, a population-based cohort study comprised exclusively of African American adults (n=5306). Analyses were restricted to 1016 participants who completed ambulatory BP monitoring at baseline in 2000 to 2004. Mean SBP and DBP levels were calculated for daytime (10:00 am-8:00 pm), 24-hour (all available readings), and nighttime (midnight-6:00 am) periods, separately. Daytime, 24-hour, and nighttime BP thresholds for ambulatory hypertension were identified using regression- and outcome-derived approaches. The composite of a cardiovascular disease or an all-cause mortality event was used in the outcome-derived approach. For this latter approach, BP thresholds were identified only for SBP because clinic DBP was not associated with the outcome. Analyses were stratified by antihypertensive medication use. RESULTS:Among participants not taking antihypertensive medication, the regression-derived thresholds for daytime, 24-hour, and nighttime SBP/DBP corresponding to clinic SBP/DBP of 140/90 mm?Hg were 134/85 mm?Hg, 130/81 mm?Hg, and 123/73 mm?Hg, respectively. The outcome-derived thresholds for daytime, 24-hour, and nighttime SBP corresponding to a clinic SBP ?140 mm?Hg were 138 mm?Hg, 134 mm?Hg, and 129 mm?Hg, respectively. Among participants taking antihypertensive medication, the regression-derived thresholds for daytime, 24-hour, and nighttime SBP/DBP corresponding to clinic SBP/DBP of 140/90 mm?Hg were 135/85 mm?Hg, 133/82 mm?Hg, and 128/76 mm?Hg, respectively. The corresponding outcome-derived thresholds for daytime, 24-hour, and nighttime SBP were 140 mm?Hg, 137 mm?Hg, and 133 mm?Hg, respectively, among those taking antihypertensive medication. CONCLUSIONS:On the basis of the outcome-derived approach for SBP and regression-derived approach for DBP, the following definitions for daytime, 24-hour, and nighttime hypertension corresponding to clinic SBP/DBP ?140/90 mm?Hg are proposed for African American adults: daytime SBP/DBP ?140/85 mm?Hg, 24-hour SBP/DBP ?135/80 mm?Hg, and nighttime SBP/DBP ?130/75 mm?Hg, respectively.
Project description:BACKGROUND:Among individuals without hypertension based on clinic blood pressure (BP), it is unclear who should be screened for masked hypertension, defined as having hypertension based on out-of-clinic BP. We hypothesized that individuals with a higher 10-year predicted atherosclerotic cardiovascular disease (ASCVD) risk, calculated using the pooled cohort risk equations, have a higher prevalence of masked hypertension. METHODS AND RESULTS:We analyzed data from the Jackson Heart Study-a population-based cohort of blacks-to determine the association of predicted ASCVD risk with masked hypertension. The sample included 644 participants, 40 to 79 years of age, with clinic systolic/diastolic BP <140/90 mm Hg, who completed ambulatory BP monitoring, were free of cardiovascular disease, and had data on factors needed to calculate ASCVD risk. Ten-year predicted ASCVD risk was calculated using the pooled cohort risk equations. Any masked hypertension was defined as masked daytime hypertension (mean daytime systolic/diastolic BP ?135/85 mm Hg), masked nighttime hypertension (mean nighttime systolic/diastolic BP ?120/70 mm Hg), or masked 24-hour hypertension (mean 24-hour systolic/diastolic BP ?130/80 mm Hg). The prevalence of any masked hypertension was 54.0%. Compared with participants in the lowest (<5%) predicted ASCVD risk category, multivariable-adjusted prevalence ratios (95% confidence interval) for any masked hypertension were 1.36 (1.03-1.79), 1.62 (1.22-2.16), and 1.91 (1.47-2.48) for those with ASCVD risk of 5% to <7.5%, 7.5% to <10%, and ?10%, respectively. The C statistic for discriminating between participants with versus without any masked hypertension was 0.681 (95% confidence interval, 0.640-0.723) for ASCVD risk and 0.703 (95% confidence interval, 0.663-0.744) for clinic systolic BP and diastolic BP. CONCLUSIONS:Higher ASCVD risk was associated with an increased prevalence of masked hypertension. Although the discrimination of ASCVD risk for masked hypertension was not superior to clinic BP, risk prediction equations may be useful for identifying the subgroup of individuals with both masked hypertension and high predicted ASCVD risk.
Project description:Masked hypertension is associated with increased risk for cardiovascular disease. Identifying modifiable risk factors for masked hypertension could provide approaches to reduce its prevalence. Life's Simple 7 is a measure of cardiovascular health developed by the American Heart Association that includes body mass index, physical activity, diet, cigarette smoking, blood pressure (BP), cholesterol, and glucose. We examined the association between cardiovascular health and masked daytime hypertension in the Jackson Heart Study, an exclusively African American cohort. Life's Simple 7 factors were assessed during a study visit and categorized as poor, intermediate, or ideal. Ambulatory BP monitoring was performed after the study visit. Using BP measured between 10:00 am and 8:00 pm on ambulatory BP monitoring, masked daytime hypertension was defined as mean clinic systolic BP/diastolic BP <140/90 mm?Hg and mean daytime systolic BP/diastolic BP ?135/85 mm?Hg. Among the 758 participants with systolic BP/diastolic BP <140/90 mm?Hg, 30.5% had masked daytime hypertension. The multivariable-adjusted prevalence ratios for masked daytime hypertension comparing participants with 2, 3, and ?4 versus ?1 ideal Life's Simple 7 factors were 0.99 (95% confidence interval [CI], 0.74-1.33), 0.77 (95% CI, 0.57-1.03), and 0.51 (95% CI, 0.33-0.79), respectively. Masked daytime hypertension was less common among participants with ideal versus poor levels of physical activity (ratio, 0.74; 95% CI, 0.56-1.00), ideal or intermediate levels pooled together versus poor diet (prevalence ratio, 0.73; 95% CI, 0.58-0.91), ideal versus poor levels of cigarette smoking (prevalence ratio, 0.61; 95% CI, 0.46-0.82), and ideal versus intermediate levels of clinic BP (prevalence ratio, 0.28, 95% CI, 0.16-0.48). Better cardiovascular health is associated with a lower preva lence of masked hypertension.
Project description:Masked hypertension, defined as nonelevated clinic blood pressure (BP) and elevated out-of-clinic BP may be an intermediary stage in the progression from normotension to hypertension. We examined the associations of out-of-clinic BP and masked hypertension using ambulatory BP monitoring with incident clinic hypertension in the Jackson Heart Study, a prospective cohort of blacks. Analyses included 317 participants with clinic BP <140/90 mm?Hg, complete ambulatory BP monitoring, who were not taking antihypertensive medication at baseline in 2000 to 2004. Masked daytime hypertension was defined as mean daytime blood pressure ?135/85 mm?Hg, masked night-time hypertension as mean night-time BP ?120/70 mm?Hg, and masked 24-hour hypertension as mean 24-hour BP ?130/80 mm?Hg. Incident clinic hypertension, assessed at study visits in 2005 to 2008 and 2009 to 2012, was defined as the first visit with clinic systolic/diastolic BP ?140/90 mm?Hg or antihypertensive medication use. During a median follow-up of 8.1 years, there were 187 (59.0%) incident cases of clinic hypertension. Clinic hypertension developed in 79.2% and 42.2% of participants with and without any masked hypertension, 85.7% and 50.4% with and without masked daytime hypertension, 79.9% and 43.7% with and without masked night-time hypertension, and 85.7% and 48.2% with and without masked 24-hour hypertension, respectively. Multivariable-adjusted hazard ratios (95% confidence interval) of incident clinic hypertension for any masked hypertension and masked daytime, night-time, and 24-hour hypertension were 2.13 (1.51-3.02), 1.79 (1.24-2.60), 2.22 (1.58-3.12), and 1.91 (1.32-2.75), respectively. These findings suggest that ambulatory BP monitoring can identify blacks at increased risk for developing clinic hypertension.
Project description: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.
Project description:Background In contrast to the general population, outcome-derived thresholds for diagnosing ambulatory hypertension in pregnancy are not yet available. We aimed to identify and compare outcome-derived ambulatory blood pressure (BP) monitoring thresholds for adverse perinatal outcomes by using approaches related and not related to clinic BP in a southern Chinese population. Methods and Results Ambulatory BP monitoring was performed in a cohort of 1768 high-risk participants in late pregnancy who were not taking antihypertensive medications. Participants were followed for composite maternal (severe complications) and neonatal (pregnancy loss, advanced neonatal care, and small for gestational age) outcomes. Modeling of clinic BP-unrelated approaches revealed a nonlinear threshold effect of ambulatory diastolic BP on the composite outcome, with increased risk for daytime ?79 mm Hg and 24-hour measurement ?76 mm Hg. For other ambulatory BP components showing linear associations with outcome, the following thresholds were identified: 131 mm Hg for daytime systolic, 121 mm Hg for nighttime systolic, 130 mm Hg for 24-hour systolic, and 73 mm Hg for night-time diastolic BP. These thresholds unrelated to clinic BP were lower than the equivalents yielding a similar probability of outcome to clinic BP of 140/90 mm Hg and were comparable with equivalents to clinic BP of 130/80 mm Hg. Conclusions Using an outcome-derived approach unrelated to clinic BP, we identified rounded thresholds to define ambulatory hypertension in at-risk women in late pregnancy in a southern Chinese population as follows: 130/80 mm Hg for daytime, 120/75 mm Hg for nighttime, and 130/75 mm Hg for 24-hour measurement. For wider clinical applicability and to align both nonpregnancy and pregnancy ambulatory BP monitoring with an outcomes-based approach, prospective, multiethnic, international studies from early pregnancy onward will be required.
Project description:Outcome-driven recommendations about time intervals during which ambulatory blood pressure should be measured to diagnose white-coat or masked hypertension are lacking. We cross-classified 8237 untreated participants (mean age, 50.7 years; 48.4% women) enrolled in 12 population studies, using ?140/?90, ?130/?80, ?135/?85, and ?120/?70 mm Hg as hypertension thresholds for conventional, 24-hour, daytime, and nighttime blood pressure. White-coat hypertension was hypertension on conventional measurement with ambulatory normotension, the opposite condition being masked hypertension. Intervals used for classification of participants were daytime, nighttime, and 24 hours, first considered separately, and next combined as 24 hours plus daytime or plus nighttime, or plus both. Depending on time intervals chosen, white-coat and masked hypertension frequencies ranged from 6.3% to 12.5% and from 9.7% to 19.6%, respectively. During 91 046 person-years, 729 participants experienced a cardiovascular event. In multivariable analyses with normotension during all intervals of the day as reference, hazard ratios associated with white-coat hypertension progressively weakened considering daytime only (1.38; P=0.033), nighttime only (1.43; P=0.0074), 24 hours only (1.21; P=0.20), 24 hours plus daytime (1.24; P=0.18), 24 hours plus nighttime (1.15; P=0.39), and 24 hours plus daytime and nighttime (1.16; P=0.41). The hazard ratios comparing masked hypertension with normotension were all significant (P<0.0001), ranging from 1.76 to 2.03. In conclusion, identification of truly low-risk white-coat hypertension requires setting thresholds simultaneously to 24 hours, daytime, and nighttime blood pressure. Although any time interval suffices to diagnose masked hypertension, as proposed in current guidelines, full 24-hour recordings remain standard in clinical practice.
Project description:Isolated nocturnal hypertension (INH), defined as nocturnal without daytime hypertension on ambulatory blood pressure (BP) monitoring (ABPM), has been observed to be associated with an increased risk of cardiovascular disease (CVD) events and mortality. The aim of this study was to determine the short-term reproducibility of INH.The Improving the Detection of Hypertension Study enrolled a community-based sample of adults (N = 282) in upper Manhattan without CVD, renal failure, or treated hypertension. Each participant completed two 24-hour ABPM recordings (ABPM1: first recording and ABPM2: second recording) with a mean ± SD time interval of 33 ± 17 days between recordings. Daytime hypertension was defined as mean awake systolic/diastolic BP ? 135/85 mm Hg; nocturnal hypertension as mean sleep systolic/diastolic BP ? 120/70 mm Hg; INH as nocturnal without daytime hypertension; isolated daytime hypertension (IDH) as daytime without nocturnal hypertension; day and night hypertension (DNH) as daytime and nocturnal hypertension, and any ambulatory hypertension as having daytime and/or nocturnal hypertension.On ABPM1, 26 (9.2%), 21 (7.4%), and 50 (17.7%) participants had INH, IDH, and DNH, respectively. On ABPM2, 24 (8.5%), 19 (6.7%), and 54 (19.1%) had INH, IDH, and DNH, respectively. The kappa statistics were 0.21 (95% confidence interval (CI) 0.04-0.38), 0.25 (95% CI 0.06-0.44), and 0.65 (95% CI 0.53-0.77) for INH, IDH, and DNH respectively; and 0.72 (95% CI 0.63-0.81) for having any ambulatory hypertension.Our results suggest that INH and IDH are poorly reproducible phenotypes, and that ABPM should be primarily used to identify individuals with daytime hypertension and/or nocturnal hypertension.
Project description:Guidelines recommend measuring out-of-clinic blood pressure (BP) to identify masked hypertension (MHT) defined by out-of-clinic BP in the hypertensive range among individuals with clinic-measured BP not in the hypertensive range. The aim of this study was to determine the overlap between ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM) for the detection of MHT. We analyzed data from 333 community-dwelling adults not taking antihypertensive medication with clinic BP <140/90 mm Hg in the IDH study (Improving the Detection of Hypertension). Any MHT was defined by the presence of daytime MHT (mean daytime BP ?135/85 mm Hg), 24-hour MHT (mean 24-hour BP ?130/80 mm Hg), or nighttime MHT (mean nighttime BP ?120/70 mm Hg). Home MHT was defined as mean BP ?135/85 mm Hg on HBPM. The prevalence of MHT was 25.8% for any MHT and 11.1% for home MHT. Among participants with MHT on either ABPM or HBPM, 29.5% had MHT on both ABPM and HBPM; 61.1% had MHT only on ABPM; and 9.4% of participants had MHT only on HBPM. After multivariable adjustment and compared with participants without MHT on ABPM and HBPM, those with MHT on both ABPM and HBPM and only on ABPM had a higher left ventricular mass index (mean difference [SE], 12.7 [2.9] g/m2, P<0.001; and 4.9 [2.1] g/m2, P=0.022, respectively), whereas participants with MHT only on HBPM did not have an increased left ventricular mass index (mean difference [SE], -1.9 [4.8] g/m2, P=0.693). These data suggest that conducting ABPM will detect many individuals with MHT who have an increased cardiovascular disease risk.
Project description:The metabolic syndrome is associated with higher ambulatory blood pressure. The authors studied the association of metabolic syndrome and masked hypertension (MHT) among African Americans with clinic-measured systolic/diastolic blood pressure (SBP/DBP) <140/90 mm Hg in the Jackson Heart Study. MHT was defined as daytime, nighttime, or 24-hour hypertension on ambulatory blood pressure monitoring. Among 359 participants not taking antihypertensive medication, the metabolic syndrome was associated with MHT (prevalence ratio, 1.38; 95% confidence interval, 1.10-1.74]). When metabolic syndrome components (clinic SBP/DBP 130-139/85-89 mm Hg, abdominal obesity, impaired glucose, low high-density lipoprotein cholesterol, high triglycerides) were analyzed separately, only clinic SBP/DBP 130-139/85-89 mm Hg was associated with MHT (prevalence ratio, 1.90; 95% confidence interval, 1.56-2.32]). The metabolic syndrome was not associated with MHT among participants not taking antihypertensive medication with SBP/DBP 130-139/85-89 and <130/85 mm Hg, separately, or among participants taking antihypertensive medication (n=393). Ambulatory blood pressure monitoring screening for MHT among African Americans should be considered based on clinic BP, not metabolic syndrome.