Racial impact of diurnal variations in blood pressure on cardiovascular events in chronic kidney disease

Assessment of hypertension in kidney transplantation by ambulatory blood pressure monitoring: a systematic review and meta-analysis

Background

Hypertension (HTN) is common following renal transplantation and it is associated with adverse effects on cardiovascular (CV) and graft health. Ambulatory blood pressure monitoring (ABPM) is the preferred method to characterize blood pressure (BP) status, since HTN misclassification by office BP (OBP) is quite common in this population. We performed a systematic review and meta-analysis aimed at determining the clinical utility of 24-h ABPM and its potential implications for the management of HTN in this population.

Methods

Ovid-MEDLINE and PubMed databases were searched for interventional or observational studies enrolling adult kidney transplant recipients (KTRs) undergoing 24-h ABP readings compared with OBP or home BP. The main outcome was the proportion of KTRs diagnosed with HTN by ABPM, home or OBP recordings. Additionally, day-night BP variability and dipper/non-dipper status were assessed.

Results

Forty-two eligible studies (4115 participants) were reviewed. A cumulative analysis including 27 studies (3481 participants) revealed a prevalence of uncontrolled HTN detected by ABPM of 56% [95% confidence interval (CI) 46-65%]. The pooled prevalence of uncontrolled HTN according to OBP was 47% (95% CI 36-58%) in 25 studies (3261 participants). Very few studies reported on home BP recordings. The average concordance rate between OBP and ABPM measurements in classifying patients as controlled or uncontrolled hypertensive was 66% (95% CI 59-73%). ABPM revealed HTN phenotypes among KTRs. Two pooled analyses of 11 and 10 studies, respectively, revealed an average prevalence of 26% (95% CI 19-33%) for masked HTN (MHT) and 10% (95% CI 6-17%) for white-coat HTN (WCH). The proportion of non-dippers was variable across the 28 studies that analysed dipping status, with an average prevalence of 54% (95% CI 45-63%).

Conclusions

In our systematic review, comparison of OBP versus ABP measurements disclosed a high proportion of MHT, uncontrolled HTN and, to a lesser extent, WCH in KTRs. These results suggest that HTN is not adequately diagnosed and controlled by OBP recordings in this population. Furthermore, the high prevalence of non-dippers confirmed that circadian rhythm is commonly disturbed in KTRs.

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.

Efficacy and safety of a combination antihypertensive drug (olmesartan plus azelnidipine): "Issues with hypertension studies in real-world practice"

Background: This study investigated whether a combination drug containing an angiotensin II receptor blocker (ARB) and a calcium channel blocker (CCB) could provide effective antihypertensive therapy.Methods: A multicenter, prospective, open-label study was conducted at the clinics of Clinical Research Network. The subjects had uncontrolled blood pressure (BP) despite ARB or CCB monotherapy. The effect on both office and home BP was examined after patients switched to a combination drug (REZ: containing 20 mg of olmesartan [OL] and 16 mg of azelnidipine [AZ]).Results: A total of 78 patients were enrolled. After switching to REZ, a significant and sustained reduction of office BP was observed. The proportion of patients who achieved the target for both office and home BP was an increase from 0% to 55%. Switching from amlodipine to REZ resulted in a significant and sustained decrease of office and home BP. There was also a significant decrease of home pulse rate (PR), but office PR was unchanged. To determine the accuracy of the BP and PR values reported by patients, the frequency of each number as the first digit was determined. The frequency of "0" was extremely high for both office and home BP values, and the same was noted for home PR values.Conclusion: The results of this study suggested that switching from a single drug to combination therapy with REZ could achieve a stronger antihypertensive effect. However, concern was raised regarding the methods of BP and PR measurement and recording in this clinical trial involving general practitioners.

Ambulatory blood pressure monitoring and diabetes complications: Targeting morning blood pressure surge and nocturnal dipping

Ambulatory blood pressure monitoring (ABPM) correlates more closely to organ damages than clinic blood pressure (BP). In the current study we aimed to investigate the association between micro- and macrovascular complications of diabetes and both diurnal and nocturnal variability in BP.A total of 192 patients with type 2 diabetes (T2DM) who had complete data on ABPM were selected. BP categories were defined based on 2017 ACC/American Heart Association BP guideline. The cross-sectional association between different BP phenotypes and diabetes complications including cardiovascular disease (CVD), nephropathy, retinopathy, and neuropathy was assessed using multiple logistic regression models adjusted for age, sex, body mass index, hypertension (HTN), hemoglobin A1c, fasting blood glucose (FBG), triglyceride (TG), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total cholesterol.Approximately 48.9% of participants with T2DM had 24-hour HTN. The prevalence of daytime, nighttime, and clinic HTN were 35.9%, 96.3%, and 53.1%, respectively. Approximately 54.2% of participants had nondipping nocturnal pattern and 28.6% were risers. Nondipping nocturnal BP was associated with CVD, neuropathy, and retinopathy (P = .05, .05, and .014, respectively). Sleep trough morning blood pressure surge (MBPS) was associated with neuropathy (P = .023). Neuropathy was also associated with other components of MBPS (P < .05).We demonstrated that diabetic neuropathy was associated with all the components of MBPS and abnormal dipping status. Our results indicated loss of nocturnal BP dipping but not MBPS as a risk factor for CVD and retinopathy in patients with T2DM. Our findings once again highlighted the importance of ambulatory BP monitoring and targeted antihypertensive therapy directed toward to restore normal circadian BP in patients with T2DM.

Morning blood pressure surge: pathophysiology, clinical relevance and therapeutic aspects

Morning hours are the period of the day characterized by the highest incidence of major cardiovascular events including myocardial infarction, sudden death or stroke. They are also characterized by important neurohormonal changes, in particular, the activation of sympathetic nervous system which usually leads to a rapid increase in blood pressure (BP), known as morning blood pressure surge (MBPS). It was hypothesized that excessive MBPS may be causally involved in the pathogenesis of cardiovascular events occurring in the morning by inducing hemodynamic stress. A number of studies support an independent relationship of MBPS with organ damage, cerebrovascular complications and mortality, although some heterogeneity exists in the available evidence. This may be due to ethnic differences, methodological issues and the confounding relationship of MBPS with other features of 24-hour BP profile, such as nocturnal dipping or BP variability. Several studies are also available dealing with treatment effects on MBPS and indicating the importance of long-acting antihypertensive drugs in this regard. This paper provides an overview of pathophysiologic, methodological, prognostic and therapeutic aspects related to MBPS.

Improvement of Diurnal Blood Pressure Variation by Azilsartan

Background

Azilsartan is an angiotensin II receptor blocker with a potent antihypertensive effect.

Methods

In a multicenter, prospective, open-label study, 265 patients with poor blood pressure control despite treatment with other angiotensin II receptor blockers were switched to 20 mg/day of azilsartan (patients on standard dosages) or 40 mg/day of azilsartan (patients on high dosages).

Results

Blood pressure was 149/83 mm Hg before switching and was significantly reduced from 1 month after switching until final assessment (132/76 mm Hg, P < 0.001). The pulse rate was 72/min before switching and increased significantly from 3 months after switching until final assessment (74/min, P < 0.005). A significant decrease of home morning systolic and diastolic pressure was observed from 1 and 3 months, respectively. Home morning blood pressure was 143/82 mm Hg before switching and 130/76 mm Hg at final assessment (P < 0.01). The morning-evening difference of systolic blood pressure decreased from 14.6 to 6.6 mm Hg after switching (P = 0.09). The estimated glomerular filtration rate was significantly decreased at 3, 6, and 12 months after switching, and serum uric acid was significantly increased at 12 months. No serious adverse events occurred.

Conclusion

Azilsartan significantly reduced the blood pressure and decreased diurnal variation in patients responding poorly to other angiotensin II receptor blockers.

Associations of Blood Pressure Dipping Patterns With Left Ventricular Mass and Left Ventricular Hypertrophy in Blacks: The Jackson Heart Study

Background

Abnormal diurnal blood pressure (BP), including nondipping patterns, assessed using ambulatory BP monitoring, have been associated with increased cardiovascular risk among white and Asian adults. We examined the associations of BP dipping patterns (dipping, nondipping, and reverse dipping) with cardiovascular target organ damage (left ventricular mass index and left ventricular hypertrophy), among participants from the Jackson Heart Study, an exclusively black population–based cohort.

Methods and Results

Analyses included 1015 participants who completed ambulatory BP monitoring and had echocardiography data from the baseline visit. Participants were categorized based on the nighttime to daytime systolic BP ratio into 3 patterns: dipping pattern (≤0.90), nondipping pattern (>0.90 to ≤1.00), and reverse dipping pattern (>1.00). The prevalence of dipping, nondipping, and reverse dipping patterns was 33.6%, 48.2%, and 18.2%, respectively. In a fully adjusted model, which included antihypertensive medication use and clinic and daytime systolic BP, the mean differences in left ventricular mass index between reverse dipping pattern versus dipping pattern was 8.3±2.1 g/m² (P<0.001) and between nondipping pattern versus dipping pattern was −1.0±1.6 g/m² (P=0.536). Compared with participants with a dipping pattern, the prevalence ratio for having left ventricular hypertrophy was 1.65 (95% CI, 1.05–2.58) and 0.96 (95% CI, 0.63–1.97) for those with a reverse dipping pattern and nondipping pattern, respectively.

Conclusions

In this population‐based study of blacks, a reverse dipping pattern was associated with increased left ventricular mass index and a higher prevalence of left ventricular hypertrophy. Identification of a reverse dipping pattern on ambulatory BP monitoring may help identify black at increased risk for cardiovascular target organ damage.

Prospective analysis of the association of ambulatory blood pressure characteristics with incident chronic kidney disease

OBJECTIVE

Ambulatory blood pressure measurement allows quantification of diurnal changes in blood pressure. While decreased nocturnal blood pressure dipping and elevated morning blood pressure surge are associated with an increased risk of cardiovascular events, the utility of ambulatory blood pressure measurements to predict renal events is unclear. African Americans, in addition to having an increased risk of chronic kidney disease (CKD), also have an increased prevalence of hypertension. Thus, we selected an African American population to study the association of ambulatory blood pressure parameters with incidence of CKD.

METHODS

Prospective cohort study of 603 participants with normal renal function enrolled in the Jackson Heart Study who underwent baseline 24-h ambulatory blood pressure monitoring between 2000 and 2004, with median follow-up of 8.1 years. We analyzed the association of nocturnal dipping and morning surge with both incident CKD [estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m] and annual rate of eGFR decline. In additional analyses, we examined the relation of nocturnal, daytime, white-coat, and masked hypertension with CKD incidence.

RESULTS

We found that 10% higher nocturnal dipping was significantly associated with a decreased risk of incident CKD [odds ratio (OR) 0.55, 95% confidence interval (CI) 0.32-0.96] and a 0.4 ml/min per 1.73 m slower annual decline in eGFR. Morning surge was not associated with the incidence of CKD. Additional analyses revealed that isolated nocturnal hypertension and mean asleep SBP were associated with a nonsignificantly higher risk of CKD (OR 2.34, 95% CI 0.90-6.08) and (OR 1.31, 95% CI 0.99-1.72), respectively, in fully adjusted models.

CONCLUSIONS

Loss of nocturnal blood pressure dipping, but not morning blood pressure surge, may promote the decline in GFR and increase the risk for development of CKD in high-risk individuals.