Night-time blood pressure is associated with the development of chronic kidney disease in a general population: the Ohasama Study

Outpatient management of essential hypertension: a review based on the latest clinical guidelines

Background: Essential hypertension, a prevalent cardiovascular condition, poses a significant health burden worldwide. Based on the latest American clinical guidelines, half of adults in the United States have hypertension. Of these, only about a half are treated and about a quarter are adequately controlled for hypertension. Given its impact on morbidity and mortality, ensuring effective management of high blood pressure is crucial to reduce associated risks and improve patient outcomes.Objective: This review aims to provide a comprehensive and up-to-date summary of the latest cardiology guidelines and evidence-based research on essential hypertension, with a focus on guiding outpatient clinical practice.Methods: The review evaluates both non-pharmacological approaches and pharmacological interventions to offer clinicians practical insights. Notably, it emphasizes the importance of individualized treatment plans tailored to patients' specific risk profiles and comorbidities.Results: By consolidating the latest advancements in hypertension management, this review provides clinicians with an up-to-date reference, offering a nuanced understanding of treatment goals and strategies.Conclusion: Through the incorporation of evidence-based recommendations, healthcare practitioners can optimize patient care, mitigate potential complications, and improve overall outcomes in essential hypertension.

Ambulatory blood pressure as risk factor for long-term kidney function decline in the general population: a distributional regression approach

The results of randomized controlled trials are unclear about the long-term effect of blood pressure (BP) on kidney function assessed as the glomerular filtration rate (GFR) in persons without chronic kidney disease or diabetes. The limited duration of follow-up and use of imprecise methods for assessing BP and GFR are important reasons why this issue has not been settled. Since a long-term randomized trial is unlikely, we investigated the association between 24-h ambulatory BP (ABP) and measured GFR in a cohort study with a median follow-up of 11 years. The Renal Iohexol Clearance Survey (RENIS) cohort is a representative sample of persons aged 50 to 62 years without baseline cardiovascular disease, diabetes, or kidney disease from the general population of Tromsø in northern Norway. ABP was measured at baseline, and iohexol clearance at baseline and twice during follow-up. The study population comprised 1589 persons with 4127 GFR measurements. Baseline ABP or office BP components were not associated with the GFR change rate in multivariable adjusted conventional regression models. In generalized additive models for location, scale, and shape (GAMLSS), higher daytime systolic, diastolic, and mean arterial ABP were associated with a slight shift of the central part of the GFR distribution toward lower GFR and with higher probability of GFR < 60 mL/min/1.73 m2 during follow-up (p < 0.05). The use of a distributional regression method and precise methods for measuring exposure and outcome were necessary to detect an unfavorable association between BP and GFR in this study of the general population.

Prognostic Significance of Home and Ambulatory Blood Pressure: Summary of Longitudinal Evidence from the Ohasama Study

The Ohasama Study is a long-term prospective cohort study of the general population in the town of Ohasama (currently, Hanamaki city) in Iwate Prefecture, Japan, that was started in 1986. Ohasama is a typical farming village in the Tohoku region that consists of part-time farming households that cultivate mainly fruit trees. At the start of the study, the prevention of hypertension, a main cause of strokes, was taken to be an important issue in public health activities because of the many people who died or needed care as a result of strokes in Ohasama. A home blood pressure measurement program was then begun with the aim of preventing hypertension while increasing a sense of solidarity among community residents and the awareness that "one must protect one's own health." As a result, this project became the world's first community-based epidemiological study using home blood pressure, as well as 24-hour ambulatory blood pressure, for which measurements were also initiated. In the 1990s, the Ohasama Study reported a linear "the lower, the better" relationship between out-of-office blood pressure and cardiovascular risk. To date, we have accumulated advanced evidence regarding the clinical significance of out-of-office blood pressure. Those have contributed to hypertension management guidelines around the world. This article summarizes the results of representative long-term follow-up studies of the Ohasama Study.

Cross-classification by systolic and diastolic blood pressure levels and chronic kidney disease, proteinuria, or kidney function decline

Predicting and preventing new-onset chronic kidney disease (CKD) through blood pressure (BP) measurements is worthwhile. This study assessed the risk of CKD, which was defined as proteinuria and/or an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, according to cross-classification by systolic and diastolic BP (SBP and DBP). This retrospective population-based cohort study analyzed data from 1,492,291 participants without CKD and without antihypertensive treatment in the JMDC database, which contains the annual health check-up data of Japanese aged <75 years. During a mean follow-up of 3.2 years, CKD incidence, proteinuria, and eGFR <60 mL/min/1.73 m2 occurred in 92,587, 67,021, and 28,858 participants, respectively. When the SBP/DBP <120/<80 mmHg group was set as a reference, both high SBP and DBP were significantly associated with an elevated CKD risk. DBP tended to be more strongly associated with CKD risk than SBP; the hazard ratio of CKD was 1.44-1.80 in the group with SBP/DBP of 130-139/≥90 mmHg and 1.23-1.47 in the group with SBP/DBP of ≥140/80-89 mmHg. A similar result was observed for developing proteinuria and eGFR <60 mL/min/1.73 m2. SBP/DBP ≥150/<80 mmHg was strongly associated with an elevated CKD risk due to the increased risk of eGFR decline. High BP, especially isolated high DBP levels, is a significant risk factor for CKD among individuals around middle age without kidney disease. Moreover, attention should be paid to kidney function, particularly eGFR decline, in the case of low DBP with extremely high SBP levels.

Relationship between clinic and ambulatory blood pressure and mortality: an observational cohort study in 59 124 patients

BACKGROUND

Ambulatory blood pressure provides a more comprehensive assessment than clinic blood pressure, and has been reported to better predict health outcomes than clinic or home pressure. We aimed to examine associations of clinic and 24-h ambulatory blood pressure with all-cause and cardiovascular mortality in a large cohort of primary care patients referred for assessment of hypertension.

METHODS

We did an observational cohort study using clinic and ambulatory blood pressure data obtained from March 1, 2004, to Dec 31, 2014, from the Spanish Ambulatory Blood Pressure Registry. This registry included patients from 223 primary care centres from the Spanish National Health System in all 17 regions of Spain. Mortality data (date and cause) were ascertained by a computerised search of the vital registry of the Spanish National Institute of Statistics. Complete data were available for age, sex, all blood pressure measures, and BMI. For each study participant, follow-up was from the date of their recruitment to the date of death or Dec 31, 2019, whichever occurred first. Cox models were used to estimate associations between usual clinic or ambulatory blood pressure and mortality, adjusted for confounders and additionally for alternative measures of blood pressure. For each measure of blood pressure, we created five groups (ie, fifths) defined by quintiles of that measure among those who subsequently died.

FINDINGS

During a median follow-up of 9·7 years, 7174 (12·1%) of 59 124 patients died, including 2361 (4·0%) from cardiovascular causes. J-shaped associations were observed for several blood pressure measures. Among the top four baseline-defined fifths, 24-h systolic blood pressure was more strongly associated with all-cause death (hazard ratio [HR] 1·41 per 1 - SD increment [95% CI 1·36-1·47]) than clinic systolic blood pressure (1·18 [1·13-1·23]). After adjustment for clinic blood pressure, 24-h blood pressure remained strongly associated with all-cause deaths (HR 1·43 [95% CI 1·37-1·49]), but the association between clinic blood pressure and all-cause death was attenuated when adjusted for 24-h blood pressure (1·04 [1·00-1·09]). Compared with the informativeness of clinic systolic blood pressure (100%), night-time systolic blood pressure was most informative about risk of all-cause death (591%) and cardiovascular death (604%). Relative to blood pressure within the normal range, elevated all-cause mortality risks were observed for masked hypertension (HR 1·24 [95% CI 1·12-1·37]) and sustained hypertension (1·24 [1·15-1·32]), but not white-coat hypertension, and elevated cardiovascular mortality risks were observed for masked hypertension (1·37 [1·15-1·63]) and sustained hypertension (1·38 [1·22-1·55]), but not white-coat hypertension.

INTERPRETATION

Ambulatory blood pressure, particularly night-time blood pressure, was more informative about the risk of all-cause death and cardiovascular death than clinic blood pressure.

FUNDING

Spanish Society of Hypertension, Lacer Laboratories, UK Medical Research Council, Health Data Research UK, National Institute for Health and Care Research Biomedical Research Centres (Oxford and University College London Hospitals), and British Heart Foundation Centre for Research Excellence.

Actual impact of angiotensin II receptor blocker or calcium channel blocker monotherapy on renal function in real-world patients

OBJECTIVE

This observational retrospective cohort study investigates the effect of antihypertensive therapy with angiotensin II receptor blockers (ARBs) or dihydropyridine calcium channel blockers (dCCBs) monotherapy on renal function using longitudinal real-world health data of a drug-naive, hypertensive population without kidney disease.

METHODS

Using propensity score matching, we selected untreated hypertensive participants (n = 10 151) and dCCB (n = 5078) or ARB (n = 5073) new-users based on annual health check-ups and claims between 2008 and 2020. Participants were divided by the first prescribed drug.

RESULTS

The mean age was 51 years, 79% were men and the mean estimated glomerular filtration rate (eGFR) was 78 ml/min per 1.73 m2. Blood pressure rapidly decreased by approximately 10% in both treatment groups. At the 1-year visit, eGFR levels decreased in the ARB group by nearly 2% but increased in the dCCB group by less than 1%. However, no significant difference was apparent in the annual eGFR change after the 1-year visit. The risk for composite kidney outcome (new-onset proteinuria or eGFR decline ≥30%) was lowest in the ARB group owing to their robust effect on preventing proteinuria: hazard ratio (95% confidence interval) for proteinuria was 0.90 (0.78-1.05) for the dCCB group and 0.54 (0.44-0.65) for the ARB group, compared with that for the untreated group after ending follow-up at the last visit before changing antihypertensive treatment.

CONCLUSION

From the present findings based on the real-world data, ARBs can be recommended for kidney protection even in a primary care setting. Meanwhile, dCCB treatment initially increases eGFR with no adverse effects on proteinuria.

Detailed association between serum uric acid levels and the incidence of chronic kidney disease stratified by sex in middle-aged adults

BACKGROUND AND AIMS

Chronic kidney disease (CKD) is a global health burden. Previous studies have shown a J- or U-shaped association between serum uric acid (SUA) and cardiovascular mortality. We assessed the risk of CKD incidence in a refined SUA category in middle-aged adults stratified by sex.

METHODS

We analyzed data from 138,511 participants <65 years old (29.6% women; mean age 44.1 years) without CKD at baseline acquired from the JMDC database. The Cox model was used to assess the adjusted hazard ratio (HR).

RESULTS

During the mean follow-up period of 4.68 years, 12,589 participants developed CKD. The fully adjusted HRs (95% confidence interval [CI], p-value) for CKD incidence in men with SUA <4.0, 10.0-10.9 and ≥ 11.0 mg/dL compared to men with SUA 4.0-4.9 mg/dL were 1.13 (1.01-1.26, p = 0.030), 1.98 (1.32-2.97, p = 0.0010), and 3.74 (1.68-8.35, p = 0.0013), respectively. The fully adjusted HRs for CKD incidence in women with SUA <4.0, 8.0-8.9, and ≥9.0 mg/dL compared to women with SUA 4.0-4.9 mg/dL were 1.08 (1.01-1.16, p = 0.032), 2.39 (1.07-5.35, p = 0.034), and 3.20 (0.80-12.8, p = 0.10), respectively.

CONCLUSIONS

Both high and low SUA levels were identified as risk factors for CKD incidence in middle-aged men and women. The association of SUA levels with the increase in the risk of CKD incidence differed by sex, and the range of SUA levels associated with an increase in the risk of CKD incidence varied by sex.

Circadian variations in blood pressure and their implications for the administration of antihypertensive drugs: is dosing in the evening better than in the morning?

: Blood pressure (BP) follows a circadian rhythm with a physiological decrease during the night. Studies have demonstrated that nocturnal BP as well as its dipping pattern during night-time have a significant prognostic importance for mortality and the occurrence of cardiovascular events. Therefore, hypertension management guidelines recommend to ascertain that patients treated for hypertension have well controlled BP values around the clock. To improve hypertension control during the night and eventually further reduce cardiovascular events, it has been proposed by some to prescribe at least one antihypertensive medication at bedtime. In this review, we have examined the data which could support the benefits of prescribing BP-lowering drugs at bedtime. Our conclusion is that there is no convincing evidence that the administration of BP-lowering drugs in the evening provides any significant advantage in terms of quality of BP control, prevention of target organ damage or reduction of cardiovascular events. Before changing practice for unproven benefits, it would be wise to wait for the results of the ongoing trials that are addressing this issue.

Lifetime risk of stroke stratified by chronic kidney disease and hypertension in the general Asian population: the Ohasama study

Lifetime risk (LTR) evaluates the absolute risk of developing a disease during the remainder of one's life. It can be a useful tool, enabling the general public to easily understand their risk of stroke. No study has been performed to determine the LTR of cardiovascular disease in patients with chronic kidney disease (CKD) with or without hypertension; therefore, we performed this study in an Asian population. We followed 1525 participants (66.0% women; age 63.1 years) in the general population of Ohasama, Japan. We defined CKD as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² and/or proteinuria. Hypertension was defined as a systolic/diastolic blood pressure ≥140/≥90 mmHg and/or the use of antihypertensive medication. We calculated the sex-specific LTR of stroke adjusted for the competing risk of death. During the mean follow-up period of 16.5 years, a first stroke occurred in 238 participants. The 10-year risk of stroke at the age of 45 years was 0.0% for men and women. The LTRs of stroke at the index age of 45 years (men/women) were 20.9%/14.5% for participants without CKD and hypertension, 34.1%/29.8% for those with CKD but not hypertension, 37.9%/27.3% for those with hypertension but not CKD, and 38.4%/36.4% for those with CKD and hypertension. The LTRs of stroke tended to be higher in younger participants than in older participants with CKD and/or hypertension. CKD contributed to the LTR of stroke, as did hypertension. The prevention of CKD and hypertension can reduce the LTR of stroke, especially in young populations.

Ambulatory Blood Pressure Profiles and Correlation with Cardiovascular Risk Factors in a Sample of 390 University Employees in Tanzania

Background

Hypertension is a major risk factor for cardiovascular morbidity and mortality. Increasingly, evidence suggests that 24-hour ambulatory blood pressure (BP) monitoring (ABPM) is more accurate than clinic BP in predicting cardiovascular risk. However, this association has not been widely studied in subSaharan Africa, especially in Tanzania.

Aim

To explore the relationship between 24-hour ABPM profiles and cardiovascular risk factors in comparison with clinic BP among Muhimbili University of Health and Allied Sciences (MUHAS) employees.

Methods

A descriptive cross-sectional study was conducted from October 2018 to February 2019. Socio-demographic and cardiovascular risk information was gathered. We used an automated ABPM device to record 24-hour ambulatory BP. Correlation between BP profiles and cardiovascular risk factors was done using Pearson’s correlation coefficient, and independent factors for hypertension were determined using logistic regression analysis. P-value of <0.05 was considered statistically significant.

Results

In total, 390 employees participated. Their mean age was 40.5 ± 8.9 years, and 53.6% were men. The mean office systolic and diastolic BP were 126±12 mmHg and 78±13 mmHg, respectively, while the corresponding values for mean 24-hour ABPM were 122±14 and 75±10 mmHg. The prevalence of hypertension was 23.1%. The prevalence of white coat hypertension was 16.2%, while masked hypertension and nocturnal non-dipping were present in 11.5 and 66.7%, respectively. Overall, the mean 24-hour systolic BP showed the strongest correlations with cardiovascular risk factors while mean office systolic BP showed least. Independent associated factors of hypertension were male gender, age ≥40 years, family history of hypertension, central obesity, raised cholesterol and uric acid levels, all p<0.01.

Conclusion

Compared to office BP, ABPM measurements had stronger correlations with cardiovascular risk factors in this population, and therefore likely to reflect true BP. ABPM has revealed high proportion of masked, white coat and nocturnal non-dipping, supporting use of ABPM to detect these clinically important BP profiles.

Blood Pressure and Chronic Kidney Disease Stratified by Gender and the Use of Antihypertensive Drugs

Background

The present study assessed the association between blood pressure (BP) and the risk of chronic kidney disease (CKD) according to gender and the use of antihypertensive drugs using data from a large‐scale health checkup.

Methods and Results

We conducted a retrospective cohort study using the JMDC database, which contains annual health checkup data of Japanese employees and their dependents aged <75 years. We included 154 692 participants (men, 69.68%; mean age, 44.74 years) without CKD. CKD was indicated by an estimated glomerular filtration rate <60 mL/min per 1.73 m² or the presence of proteinuria. During the mean follow‐up period of 4.78 years, new‐onset CKD occurred in 14 888 participants. When the normal BP group (systolic/diastolic BP <120/<80 mm Hg) without treatment was used as a reference, the hazard ratios of the high BP (130–139/80–89 mm Hg) and grade 1 (140–159/90–99 mm Hg) and grade 2 or 3 hypertension (≥160/≥100 mm Hg) groups were 1.11 (95% CI, 1.06–1.17), 1.36 (95% CI, 1.28–1.45), and 1.76 (95% CI, 1.56–1.99) for untreated men, respectively. However, in treated men, even normal BP was associated with a 1.5‐fold higher risk of CKD. The association between BP and the risk of CKD was weaker in untreated women than in untreated men. The risk of CKD in treated women with normal BP was similar to that of untreated women with normal BP.

Conclusions

Gender differences were found in the association between BP and CKD risk. Kidney function in treated individuals should be followed carefully, especially in men.

N-Terminal Pro-B-Type Natriuretic Peptide Is a Predictor of Chronic Kidney Disease in an Asian General Population - The Ohasama Study

Background: N-terminal pro-B-type natriuretic peptide (NT-proBNP) is known to increase in heart failure patients. Given that no reports have described the association between NT-proBNP and chronic kidney disease (CKD) incidence in Asian populations, we investigated this association in the Japanese population. Methods and Results: We followed up 867 participants without CKD from the general population of Ohasama, Japan. We defined CKD as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² and/or proteinuria. In accordance with previous studies, the participants were classified into 4 groups according to NT-proBNP level (<30.0, 30.0-54.9, 55.0-124.9, and ≥125.0 pg/mL). The Cox model was applied to assess adjusted hazard ratios (HR) for CKD incidence after full adjustment including baseline eGFR. Participant mean age was 59.1 years, and 587 (67.7%) were women. During the mean follow-up period of 9.7 years, 177 participants developed CKD. When the group with NT-proBNP <30.0 pg/mL was used as the reference, adjusted HR for CKD incidence in the 30.0-54.9, 55.0-124.9, and ≥125.0 pg/mL groups were 1.34 (95% CI: 0.90-2.01), 1.25 (95% CI: 0.81-1.92), and 1.83 (95% CI: 1.05-3.18), respectively. Conclusions: NT-proBNP can be significantly predictive for CKD incidence in Asian populations.

Optimal blood pressure target and measurement in patients with chronic kidney disease

The prevalence rates of hypertension and chronic kidney disease (CKD) are increasing with the aging of the population. Hypertension and CKD are closely related, and hypertension with accompanying CKD is difficult to control. This difficulty controlling blood pressure (BP) can be explained by changes in diurnal variation in BP, such as non-dipping and reverse dipping patterns, increased pulse pressure, and BP variability in CKD patients resulting in a high frequency of nocturnal hypertension or masked hypertension. CKD patients with uncontrolled or nocturnal hypertension are at increased risk for cardiovascular disease, progression of CKD, and all-cause death. Recent studies have shown that intensive reduction of systolic BP below 120 mmHg is seems to favor in CKD patients regardless of the presence or absence of diabetes. As BP control is difficult in patients with CKD, appropriate measurement of BP is important. Automated BP monitoring could reduce the so-called "white coat effect" (spike in BP) that may be triggered by measurement in a clinical setting. Moreover, out-of-office BP monitoring at home or ambulatory BP monitoring for 24 hours may provide critical information regarding diurnal BP variability and nocturnal BP in patients with CKD.

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.

Risk of incident chronic kidney disease is better reduced by bedtime than upon-awakening ingestion of hypertension medications

This trial investigated whether therapy with the entire daily dose of ≥1 hypertension medications at bedtime exerts a greater reduction in the risk of incident chronic kidney disease (CKD) than therapy with all medications upon awakening. We conducted a prospective, open-label, blinded endpoint trial of 2078 hypertensive patients without CKD (1017 men/1061 women, 53.6 ± 13.7 years of age) randomized to ingest all their prescribed hypertension medications upon awakening (n = 1041) or the entire daily dose of ≥1 of those medications at bedtime (n = 1037). During a 5.9-year median follow-up, 368 participants developed CKD. Patients of the bedtime, compared with the morning, treatment group showed (i) significantly lower asleep blood pressure (BP) mean, greater sleep-time relative BP decline, and attenuated prevalence of non-dipping at the final evaluation (38 vs. 55%; P < 0.001); and (ii) a significantly lower hazard ratio of CKD, adjusted for the significant influential characteristics of age, serum creatinine, urinary albumin, type 2 diabetes, previous cardiovascular event, asleep systolic BP mean, and sleep-time relative systolic BP decline (0.27 (95% confidence interval: 0.21-0.36); event-rate 8.3 vs. 27.1% in the bedtime and morning-treatment groups; P < 0.001). Greater benefit was observed for bedtime than awakening treatment, with angiotensin converting enzyme inhibitors and angiotensin receptor blockers. In hypertensive patients without CKD, ingestion of ≥1 BP-lowering medications at bedtime, mainly those modulating or blocking the effects of angiotensin II, compared with ingestion of all such medications upon-awakening, resulted in improved ambulatory BP control (significant further decrease of asleep BP and enhanced sleep-time relative BP decline) and reduced risk of incident CKD.

The association between home vs. ambulatory night-time blood pressure and end-organ damage in the general population

OBJECTIVE

The aim of this study was to test the agreement between night-time home and night-time ambulatory blood pressure (BP) and to compare their associations with hypertensive end-organ damage for the first time in the general population.

METHODS

A population sample of 248 participants underwent measurements for night-time home BP (three measurements on two nights with a timer-equipped home device), night-time ambulatory BP, pulse wave velocity (PWV), carotid intima-media thickness (IMT) and echocardiographic left ventricular mass index (LVMI).

RESULTS

No significant or systematic differences were observed between mean night-time ambulatory and home BPs (systolic/diastolic difference: 0.7 ± 7.6/0.2 ± 6.0 mmHg, P = 0.16/0.64). All night-time home and ambulatory BPs were positively correlated with PWV, IMT and LVMI (P < 0.01 for all). No significant differences in Pearson's correlations between end-organ damage and night-time home or ambulatory BP were observed (P ≥ 0.11 for all comparisons using Dunn and Clark's Z), except for a slightly stronger correlation between PWV and ambulatory SBP than for home SBP (r = 0.57 vs. 0.50, P = 0.03). The adjusted R of all multivariable-adjusted models for PWV, IMT or LVMI that included night-time home or ambulatory SBP/DBP were within 2/1%.

CONCLUSION

Our study demonstrates that night-time home and ambulatory measurements produce similar BP values that have comparable associations with end-organ damage in the general population even when a clinically feasible measurement protocol is used for measuring night-time home BP. In the future, night-time home BP measurement may offer a feasible and easily accessible alternative to ambulatory monitoring for the measurement of night-time BP.

Management of Hypertension in Patients with Chronic Kidney Disease

Hypertension is the leading factor in the global burden of disease. It is the predominant modifiable risk factor for stroke, heart disease, and kidney failure. Chronic kidney disease (CKD) is both a common cause and sequel of uncontrolled hypertension. The pathophysiology of CKD-associated hypertension is complex and multi-factorial. This paper reviews the key pathogenic mechanisms of CKD-associated hypertension, the importance of standardized blood pressure (BP) measurement in establishing the diagnosis and management plus the significance of ambulatory BP monitoring for assessment of diurnal BP variation commonly seen in CKD. The optimal BP target in CKD remains a matter of discussion despite recent clinical trials. Medical therapy can be difficult and challenging. In addition to lifestyle modification and dietary salt restriction, treatment may need to be individualized based on co-morbidities. Combination of antihypertensive drugs, including appropriate diuretic choice and dose, is of great significance in hypertension management in CKD.

Sleep-Time Ambulatory BP Is an Independent Prognostic Marker of CKD

The prognostic value of clinic and ambulatory BP in predicting incident CKD and whether CKD risk reduction associates with progressive treatment-induced decrease of clinic, awake, or asleep BP are unknown. We prospectively evaluated 2763 individuals without CKD, 1343 men and 1420 women (mean±SD age: 51.5±14.3 years old), with baseline ambulatory BP ranging from normotension to hypertension. On recruitment and annually thereafter (more frequently if hypertension treatment was adjusted on the basis of ambulatory BP), we simultaneously monitored BP and physical activity (wrist actigraphy) for 48 hours to accurately derive individualized mean awake and asleep BP. During a median 5.9-year follow-up, 404 participants developed CKD. Mean asleep systolic BP was the most significant predictor of CKD in a Cox proportional hazard model adjusted for age, diabetes, serum creatinine concentration, urinary albumin concentration, previous cardiovascular event, and hypertension treatment time (on awakening versus at bedtime; per 1-SD elevation: hazard ratio, 1.44; 95% confidence interval, 1.31 to 1.56; P<0.001). The predictive values of mean clinic BP and mean awake or 48-hour ambulatory BP was not significant when corrected by mean asleep BP. Analyses of BP changes during follow-up revealed 27% reduction in the risk of CKD per 1-SD decrease in mean asleep systolic BP, independent of changes in mean clinic BP or awake ambulatory BP. In conclusion, sleep-time BP is a highly significant independent prognostic marker for CKD. Furthermore, progressive treatment-induced decrease of asleep BP, a potential therapeutic target requiring ambulatory BP evaluation, might be a significant method for reducing CKD risk.

Comparison of Prognostic Values of Daytime and Night-Time Systolic Blood Pressures on Renal Outcomes in Patients With Chronic Kidney Disease

BACKGROUND

Differences in the predictive value of daytime systolic blood pressure (SBP) and night-time SBP by ambulatory blood pressure monitoring on renal outcomes have not been fully investigated in chronic kidney disease (CKD) patients. This study compared the prognostic value between daytime and night-time SBP on renal outcomes in CKD.Methods and Results:This prospective observational study included 421 patients. The composite renal endpoint was endstage renal disease (ESRD) or death. Cox models were used to determine associations of daytime and night-time SBP with renal outcomes. There were 150 renal events (ESRD, 130; death, 20). Multivariable Cox analyses demonstrated that hazard ratios (HRs) [95% confidence interval (CI)] for composite renal outcomes of every 10-mmHg increase in daytime and night-time SBP levels were 1.13 (1.02-1.26) (P=0.02) and 1.15 (1.05-1.27) (P<0.01), respectively. In addition, compared with the 1st daytime or night-time SBP quartile, HRs (95% CI) for outcomes in the 2nd, 3rd, and 4th quartiles were: daytime SBP, 1.25 (0.70-2.25), 1.09 (0.61-1.94), and 1.58 (0.88-2.85; P=0.13) (P for trend=0.16); night-time SBP, 1.09 (0.61-1.96), 1.31 (0.76-2.28), and 1.82 (1.00-3.30; P=0.049) (P for trend=0.03), respectively.

CONCLUSIONS

Night-time SBP appeared superior to daytime SBP for predicting renal outcomes in this population of patients.

Blood pressure and age-related GFR decline in the general population

BACKGROUND

Hypertension is one of the most important causes of end-stage renal disease, but it is unclear whether elevated blood pressure (BP) also accelerates the gradual decline in the glomerular filtration rate (GFR) seen in the general population with increasing age. The reason may be that most studies have considered only baseline BP and not the effects of changes in BP, antihypertensive treatment and other determinants of GFR during follow-up. Additionally, the use of GFR estimated from creatinine or cystatin C instead of measurements of GFR may have biased the results because of influence from non-GFR related confounders. We studied the relationship between BP and GFR decline using time-varying variables in a cohort representative of the general population using measurements of GFR as iohexol clearance.

METHODS

We included 1594 subjects aged 50 to 62 years without baseline diabetes, kidney-, or cardiovascular disease in the Renal Iohexol-clearance Survey in Tromsø 6 (RENIS-T6). GFR, BP, antihypertensive medication and all adjustment variables were ascertained at baseline, and at follow-up after a median observation time of 5.6 years in 1299 persons (81%). The relationship between GFR decline and BP was analyzed in linear mixed models.

RESULTS

The mean (standard deviation) GFR decline rate was 0.95 (2.23) mL/min/year. The percentage of persons with hypertension (systolic BP ≥ 140 mmHg, diastolic BP ≥ 90 mmHg or antihypertensive medication) increased from 42 to 52% between baseline and follow-up. In multivariable adjusted linear mixed models using time-varying independent variables measured at baseline and follow-up, higher systolic and diastolic BP were associated with slower GFR decline rates by 0.10 and 0.20 mL/min/year/10 mmHg, respectively (p < 0.05). The association was stronger in persons on antihypertensive medication than in others (p < 0.05 for the interaction between BP and antihypertensive medication).

CONCLUSIONS

In the medium-term, elevated BP is not associated with accelerated GFR decline in the general middle-aged population. In persons using antihypertensive medication, elevated BP is associated with a paradoxical slower GFR decline. Studies with even longer observation periods are needed to evaluate the ultimate effect of BP on kidney function.

Ambulatory versus clinic blood pressure in predicting overall subclinical target organ damage progression in essential hypertensive patients: a 3-year follow-up study

BACKGROUND

Ambulatory blood pressure (BP) was shown to predict specific subclinical target organ damage (TOD) progression better than clinic BP, whereas the usefulness of ambulatory and clinic BP measurements to predict overall TOD progression is not well established.

METHODS AND RESULTS

Clinic and 24-h ambulatory BP values were obtained in 280 patients on baseline. A total of 199 participants (mean age 62.5±9.5, 59.3% men) were followed up for an average of 39 months and overall subclinical TOD were recorded at the end of follow-up period. Patients with increased TOD number had higher baseline clinic, 24-h, day and night systolic blood pressure (SBP), and pulse pressure, but baseline ambulatory and clinic diastolic blood pressure showed no differences. Multiple logistic regression analysis showed that the independent predictors of the overall TOD number increased were clinic [relative ratio (RR)=1.023, P=0.006], 24-h (RR=1.034, P=0.005), day (RR=1.023, P=0.04) and night (RR=1.038, P=0.001) SBP, as well as 24-h (RR=1.050, P=0.005), day (RR=1.037, P=0.02) and night (RR=1.062, P=0.001) ambulatory pulse pressure, and night average diastolic blood pressure with boundary correlation (RR=1.034, P=0.048). The night-time SBP value was more strongly associated with the risk of overall increased TOD number than the daytime (RR=1.049, P=0.003) or clinic SBP (RR=1.026, P=0.02). Similarly, 24-h pulse pressure was superior to clinic (RR=1.045, P=0.02) and night-time was superior to daytime pulse pressure (RR=1.104, P=0.002).

CONCLUSION

The risk of overall subclinical TOD progression increased more with a given increase in baseline ambulatory night-time BP than baseline clinic or daytime BP in essential hypertension.

Impact of night-time blood pressure on cerebral white matter hyperintensity in elderly hypertensive patients

AIM

Cerebral white matter hyperintensity (WMH) is highly prevalent in the elderly population, and increases the risk of dementia and stroke. We investigated the relationship between ambulatory blood pressure monitoring levels and quantitatively measured WMH volumes among elderly hypertensive patients with well-controlled blood pressure (BP) to re-evaluated effective hypertension management methods to prevent the progression of WMH.

METHODS

Participants comprised 84 hypertensive patients aged between 65 and 75 years without symptomatic heart failure, ischemic heart disease, atrial fibrillation, stroke or cognitive dysfunction.

RESULTS

Linear regression analysis showed that office BP was not associated with WMH volume increases. Raised night-time systolic BP (P = 0.013) were associated with greater WMH volumes during ambulatory blood pressure monitoring. To clarify the effect of asleep systolic BP on WML volume, we then classified patients into two systolic BP groups as follows: <125 mmHg (n = 47) and ≥125 mmHg (n = 37). Baseline characteristics were almost similar in both groups, except the dipper type of circadian BP variation was significantly common in the group with night-time systolic BP <125 mmHg. However, WMH volume was greater in the group with night-time systolic BP ≥125 mmHg than that in the <125 mmHg group (9.0 ± 8.4 mL vs 4.1 ± 4.3 mL, P = 0.015).

CONCLUSION

Higher night-time systolic BP levels were observed to contribute greater WMH volumes in elderly hypertensive patients. To prevent the progression of WMH, controlling BP on the basis of ambulatory blood pressure monitoring is important.

Antihypertensive treatment decreases arterial stiffness at night but not during the day. Results from the Hypertension in the Very Elderly Trial

The main Hypertension in the Very Elderly Trial (HYVET) demonstrated a very marked reduction in cardiovascular events by treating hypertensive participants 80 years or older with a low dose, sustained release prescription of indapamide (indapamide SR, 1.5 mg) to which was added a low dose of an angiotensin converting enzyme inhibitor in two-thirds of cases (perindopril 2-4 mg). This report from the ambulatory blood pressure sub-study investigates whether changes in arterial stiffness and ambulatory blood pressure (BP) could both explain the benefits observed in the main trial. A total of 139 participants were randomized to placebo [67] and to active treatment [72] and had both day and night observations of BP and arterial stiffness as determined from the Q wave Korotkoff diastolic (QKD) interval. The QKD interval was 5.6 ms longer (p = 0.017) in the actively treated group at night than in the placebo group. This was not true for the more numerous daytime readings so that 24-h results were similar in the two groups. The QKD interval remained longer at night in the actively treated group even when adjusted for systolic pressure, heart rate and height. The reduced arterial stiffness at night may partly explain the marked benefits observed in the main trial.

Elevated blood pressure is not associated with accelerated glomerular filtration rate decline in the general non-diabetic middle-aged population

Although hypertension is a risk factor for end-stage renal disease, this complication develops in only a minority of hypertensive patients. Whether non-malignant hypertension itself is sufficient to cause reduced glomerular filtration rate (GFR) is unclear. Therefore, we investigated whether elevated blood pressure (BP) was associated with accelerated GFR decline in the general population. The study was based on the Renal Iohexol Clearance Survey in Tromsø 6 (RENIS-T6), which included a representative sample of 1594 individuals aged 50 to 62 years from the general population without baseline diabetes or kidney or cardiovascular disease. GFR was measured as iohexol clearance at baseline and follow-up after a median observation time of 5.6 years. BP was measured according to a standardized procedure. The mean (SD) GFR decline rate was 0.95 (2.23) ml/min/yr. In multivariable adjusted linear mixed regressions with either baseline systolic or diastolic BP as the independent variable, there were no statistically significant associations with GFR decline. Thus, elevated BP is not associated with accelerated mean GFR decline in the general middle-aged population. Hence, additional genetic and environmental factors are probably necessary for elevated BP to develop manifest chronic kidney disease in some individuals.

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.

Hypertension in Chronic Kidney Disease

Hypertension, a global public health problem, is currently the leading factor in the global burden of disease. It is the major modifiable risk factor for heart disease, stroke and kidney failure. Chronic kidney disease (CKD) is both a common cause of hypertension and CKD is also a complication of uncontrolled hypertension. The interaction between hypertension and CKD is complex and increases the risk of adverse cardiovascular and cerebrovascular outcomes. This is particularly significant in the setting of resistant hypertension commonly seen in patient with CKD. The pathophysiology of CKD associated hypertension is multi-factorial with different mechanisms contributing to hypertension. These pathogenic mechanisms include sodium dysregulation, increased sympathetic nervous system and alterations in renin angiotensin aldosterone system activity. Standardized blood pressure (BP) measurement is essential in establishing the diagnosis and management of hypertension in CKD. Use of ambulatory blood pressure monitoring provides an additional assessment of diurnal variation in BP commonly seen in CKD patients. The optimal BP target in the treatment of hypertension in general and CKD population remains a matter of debate and controversial despite recent guidelines and clinical trial data. Medical therapy of patients with CKD associated hypertension can be difficult and challenging. Additional evaluation by a hypertension specialist may be required in the setting of treatment resistant hypertension by excluding pseudo-resistance and treatable secondary causes. Treatment with a combination of antihypertensive drugs, including appropriate diuretic choice, based on estimated glomerular filtration rate, is a key component of hypertension management in CKD patients. In addition to drug treatment non-pharmacological approaches including life style modification, most important of which is dietary salt restriction, should be included in the management of hypertension in CKD patients.

Management of hypertension in chronic kidney disease

Hypertension is a common comorbidity in patients with impaired kidney function. The kidney exerts a marked degree of control over blood pressure through various mechanisms, such as by regulating sodium balance and hormone secretion through the activity of the renin-angiotensin system. The kidney is susceptible to injury, and if already damaged can be at risk of further loss of function as a consequence of elevated blood pressure. Once elevated blood pressure is identified, a combination of sensible lifestyle measures, such as sodium restriction and weight loss, with pharmacological intervention to reduce blood pressure will usually achieve blood pressure goals. In this Review, we outline the importance of blood pressure control for patients with chronic kidney disease (CKD), the mechanisms that affect blood pressure control, and the basis for non-drug and drug therapies. We further discuss the rationale for <140 mmHg systolic and <90 mmHg diastolic targets for blood pressure in patients with CKD, with consideration for tighter targets in the setting of proteinuria.

Diurnal variation in blood pressure and arterial stiffness in chronic kidney disease: the role of endothelin-1

Hypertension and arterial stiffness are important independent cardiovascular risk factors in chronic kidney disease (CKD) to which endothelin-1 (ET-1) contributes. Loss of nocturnal blood pressure (BP) dipping is associated with CKD progression, but there are no data on 24-hour arterial stiffness variation. We examined the 24-hour variation of BP, arterial stiffness, and the ET system in healthy volunteers and patients with CKD and the effects on these of ET receptor type A receptor antagonism (sitaxentan). There were nocturnal dips in systolic BP and diastolic BP and pulse wave velocity, our measure of arterial stiffness, in 15 controls (systolic BP, −3.2±4.8%, P<0.05; diastolic BP, −6.4±6.2%, P=0.001; pulse wave velocity, −5.8±5.2%, P<0.01) but not in 15 patients with CKD. In CKD, plasma ET-1 increased by 1.2±1.4 pg/mL from midday to midnight compared with healthy volunteers (P<0.05). Urinary ET-1 did not change. In a randomized, double-blind, 3-way crossover study in 27 patients with CKD, 6-week treatment with placebo and nifedipine did not affect nocturnal dips in systolic BP or diastolic BP between baseline and week 6, whereas dipping was increased after 6-week sitaxentan treatment (baseline versus week 6, systolic BP: −7.0±6.2 versus −11.0±7.8 mm Hg, P<0.05; diastolic BP: −6.0±3.6 versus −8.3±5.1 mm Hg, P<0.05). There was no nocturnal dip in pulse pressure at baseline in the 3 phases of the study, whereas sitaxentan was linked to the development of a nocturnal dip in pulse pressure. In CKD, activation of the ET system seems to contribute not only to raised BP but also the loss of BP dipping. The clinical significance of these findings should be explored in future clinical trials.