Aldosterone-to-renin ratio and nocturnal blood pressure decline in a general population: the Ohasama study

The association between blood pressure variability and renal damage in patients with primary aldosteronism

This research examines the association between blood pressure variability (BPV) and renal damage in a cohort of 129 primary aldosteronism (PA) patients, employing ambulatory blood pressure monitoring (ABPM) for comparative analysis with individuals diagnosed with essential hypertension (EH). The study reveals that PA patients exhibited significantly elevated levels of cystatin C and urine microalbumin/creatinine ratio (UACR). Additionally, a higher prevalence of non-dipping blood pressure patterns in PA patients suggests an increased risk of circadian blood pressure regulation disturbances. Notably, while most BPV indices were comparable between the two groups, the standard deviation of 24-h weighted diastolic blood pressure was markedly lower in the PA cohort, distinguishing it as a unique variable. Through multiple linear regression analysis, the duration of hypertension, angiotensin II concentrations, and daytime systolic blood pressure standard deviation emerged as significant determinants of estimated glomerular filtration rate (eGFR) in PA patients. Furthermore, UACR was significantly influenced by variables including the 24-h weighted standard deviation (wSD) of systolic BP, glycosylated hemoglobin levels, nocturnal systolic BP peaks, aldosterone-renin ratio (ARR), and total cholesterol, with the most pronounced association observed with the 24-h wSD of systolic BP (β = 0.383).The study also found significant correlations between the 24-h wSD of systolic BP, ARR, HbA1c, serum potassium levels, and 24-h urinary microalbumin, underscoring the critical role of the 24-h wSD of systolic BP (β = 0.267). These findings underscore the imperative of an integrated management strategy for PA, addressing the intricate interconnections among metabolic abnormalities, blood pressure variability, and renal health outcomes.

Nocturnal systolic blood pressure dipping and progression of chronic kidney disease

The relationship between declining nocturnal blood pressure (BP) and adverse cardiovascular outcomes is well-recognized. However, the relationship between diurnal BP profile and the risk of chronic kidney disease (CKD) progression is unclear. Herein, we examined the association between nocturnal systolic SBP (SBP) dipping and CKD progression in 1061 participants at the Cardiovascular and Metabolic Disease Etiology Research Center-High Risk (CMERC-HI). The main exposure was diurnal systolic BP (SBP) profile and diurnal SBP difference ([nighttime SBP-daytime SBP] × 100/daytime SBP). The primary outcome was CKD progression, defined as a composite of ≥ a 50% decline in the estimated glomerular filtration rate from baseline or the initiation of kidney replacement therapy. During 4749 person-years of follow-up (median, 4.8 years), the composite outcome occurred in 380 (35.8%) participants. Compared to dippers, the hazard ratios (HRs) for the risk of adverse kidney outcomes were 1.02 (95% confidence interval [CI], 0.64-1.62), 1.30 (95% CI, 1.02-1.66), and 1.40 (95% CI, 1.03-1.90) for extreme dipper, non-dipper, and reverse dipper, respectively. In a continuous modeling, a 10% increase in diurnal SBP difference was associated with a 1.21-fold (95% CI, 1.07-1.37) higher risk of CKD progression. Thus, decreased nocturnal SBP decline was associated with adverse kidney outcomes in patients with CKD. Particularly, patients with non-dipping and reverse dipping patterns were at higher risk for CKD progression than those with a dipping pattern.

Defining the nocturnal period in 24-h ambulatory blood pressure monitoring: a comparison of three methods

OBJECTIVES

The purpose of our study was to compare three definitions of ambulatory blood pressure (BP) nocturnal period and to assess their agreement in determining nocturnal BP dipping patterns.

METHODS

We investigated 69 subjects with metabolic syndrome, aged 50-55 years. In all subjects, we assessed 24-h BP monitoring, electrocardiogram and actigraphy profiles. The nocturnal period was defined in three ways: as a fixed narrow nighttime period from 01:00 to 06:00, as a self-reported sleeping period and as a disappearance and onset of physical activity recorded by the actigraph.

RESULTS

Our study revealed a significant discrepancy between the self-reported and actigraphy-based nocturnal periods (P < 0.001). In addition, different definitions of the nighttime yielded significant differences in determining nondipping, extreme dipping and dipping BP patterns, the identification of the latter being affected the most. The actigraphy-based approach best aligned with the fixed-time determination of the nocturnal period: Cohen's kappa coefficient for the nondipping pattern was 0.78 (0.58-1), for the dipping pattern 0.75 (0.59-0.91) and for the extreme dipping pattern 0.81 (0.65-0.97). In comparison to the self-reported determination of the nocturnal period, using the actigraphy-based approach resulted in reclassifying the nocturnal BP pattern in 20.3% of subjects.

CONCLUSIONS

The lack of agreement between fixed-time, self-reported and actigraphy-based determinations of the nighttime period affects the identification of the nocturnal BP patterns. In comparison to the self-reported nocturnal period estimation, the actigraphy-based approach results in the reclassification of BP dipping status in every fifth subject.

Pharmacologic management of nocturnal polyuria: a contemporary assessment of efficacy, safety, and progress toward individualized treatment

This narrative review synthesizes current evidence on the medical management of nocturnal polyuria, including antidiuretic replacement therapy as well as other emerging modalities, with particular emphasis on areas of active investigation and future research directions. Relative to earlier formulations, the pharmacological profiles of novel desmopressin acetate nasal spray and orally disintegrating tablet formulations appear favorable in optimizing the balance between efficacy and safety. Additionally, several highly selective small-molecule arginine vasopressin 2 receptor agonists are under active development, while appropriately timed short-acting diuretics, pharmacotherapy for hypertension, nonsteroidal anti-inflammatory drugs, and sex hormone replacement therapy are also a focal point of extensive ongoing nocturnal polyuria research. Emerging laboratory technologies now make feasible a sub-stratification of nocturnal polyuria patients into substrate-based phenotypes for individualized treatment. An increasingly refined understanding of the pathogenesis of nocturnal polyuria, and arginine vasopressin dysregulation in particular, has also introduced new opportunities for point-of-care testing in patients with nocturnal polyuria.

Confounders of the aldosterone-to-renin ratio when used as a screening test in hypertensive patients: A critical analysis of the literature

The aldosterone‐to‐renin ratio (ARR) is a common screening test for primary aldosteronism in hypertensives. However, there are many factors which could confound the ARR test result and reduce the accuracy of this test. The present review's objective is to identify these factors and to describe to what extent they affect the ARR. Our analysis revealed that sex, age, posture, and sodium‐intake influence the ARR, whereas assay techniques do not. Race and body mass index have an uncertain effect on the ARR. We conclude that several factors can affect the ARR. Not taking these factors into account could lead to misinterpretation of the ARR.

Effects of continuous positive airway pressure treatment on aldosterone excretion in patients with obstructive sleep apnoea and resistant hypertension: a randomized controlled trial

OBJECTIVE

Aldosterone excess has been equally associated with resistant hypertension (RHT) and obstructive sleep apnoea (OSA). We conducted a randomized controlled study to assess the effect of continuous positive airway pressure (CPAP) treatment on 24-h urinary aldosterone excretion in patients with RHT and moderate/severe OSA.

METHODS

A total of 117 patients were randomized (57 CPAP and 60 control groups). Aldosterone excretion was determined by 24 h urine (24h-UAldo) collected at randomization and after 6 months of follow-up. Twenty-four hour UAldo differences were assessed by general linear model with the allocation group (CPAP or control) as a fixed factor adjusted for their respective baseline values. Both intention-to-treat and per-protocol (45 patients with optimal adherence to CPAP) analyses were performed.

RESULTS

Baseline 24h-UAldo was higher in severe OSA than in moderate OSA patients. After CPAP treatment, there was a borderline significant reduction in 24h-UAldo [mean difference: -2.5 μg/24 h; 95% confidence interval (95% CI): -5.3 to +0.3 μg/24 h; P = 0.07] in intention-to-treat analysis, whereas in the per-protocol analysis, the CPAP group had a greater reduction in 24h-UAldo than the control group (mean difference: -3.3 μg/24 h; 95% CI: -6.1 to -0.4 μg/24 h; P = 0.027). This effect occurred solely in patients with uncontrolled ambulatory BPs, and was more pronounced in those with the nondipping pattern, not using spironolactone, less obese, and with lowest sleep SaO2 levels.

CONCLUSION

Only optimal CPAP treatment reduced aldosterone excretion in patients with uncontrolled RHT, while on intention-to-treat the effect was borderline. Although nondefinitive, our results suggest that CPAP treatment might improve cardiovascular outcomes by reducing aldosterone excess in resistant hypertensive individuals with OSA.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01508754.

Prognostic Effect of the Nocturnal Blood Pressure Fall in Hypertensive Patients: The Ambulatory Blood Pressure Collaboration in Patients With Hypertension (ABC-H) Meta-Analysis

The prognostic importance of the nocturnal systolic blood pressure (SBP) fall, adjusted for average 24-hour SBP levels, is unclear. The Ambulatory Blood Pressure Collaboration in Patients With Hypertension (ABC-H) examined this issue in a meta-analysis of 17 312 hypertensives from 3 continents. Risks were computed for the systolic night-to-day ratio and for different dipping patterns (extreme, reduced, and reverse dippers) relative to normal dippers. ABC-H investigators provided multivariate adjusted hazard ratios (HRs), with and without adjustment for 24-hour SBP, for total cardiovascular events (CVEs), coronary events, strokes, cardiovascular mortality, and total mortality. Average 24-hour SBP varied from 131 to 140 mm Hg and systolic night-to-day ratio from 0.88 to 0.93. There were 1769 total CVEs, 916 coronary events, 698 strokes, 450 cardiovascular deaths, and 903 total deaths. After adjustment for 24-hour SBP, the systolic night-to-day ratio predicted all outcomes: from a 1-SD increase, summary HRs were 1.12 to 1.23. Reverse dipping also predicted all end points: HRs were 1.57 to 1.89. Reduced dippers, relative to normal dippers, had a significant 27% higher risk for total CVEs. Risks for extreme dippers were significantly influenced by antihypertensive treatment (P<0.001): untreated patients had increased risk of total CVEs (HR, 1.92), whereas treated patients had borderline lower risk (HR, 0.72) than normal dippers. For CVEs, heterogeneity was low for systolic night-to-day ratio and reverse/reduced dipping and moderate for extreme dippers. Quality of included studies was moderate to high, and publication bias was undetectable. In conclusion, in this largest meta-analysis of hypertensive patients, the nocturnal BP fall provided substantial prognostic information, independent of 24-hour SBP levels.

Association of aldosterone-to-renin ratio with hypertension differs by sodium intake: the Ohasama study

BACKGROUND

In cross-sectional studies, the aldosterone-to-renin ratio (ARR) has been reported to be associated with hypertension under conditions of higher sodium intake. The objective of this prospective study was to investigate the association between ARR and the development of hypertension in community residents stratified by dietary sodium intake.

METHODS

From the general population of Ohasama, we obtained plasma renin activity (PRA) and plasma aldosterone concentrations (PACs) for 608 participants (mean age = 57.6 years; 71.4% women) without hypertension at baseline. Using the Cox model, we computed the adjusted hazard ratio (HR) of natural log-transformed ARR (lnARR) for the development of hypertension, defined as blood pressure ≥140/90mm Hg or start of treatment with antihypertensive drugs during follow-up.

RESULTS

During a mean follow-up of 6.8 years, 298 participants developed hypertension. The median PRA, PAC, and ARR were 1.2ng/ml/hour, 6.6ng/dl, and 5.5ng/dl per ng/ml/hour, respectively. Each 1 SD increase in lnARR was associated with an increased risk for the development of hypertension in participants overall (HR = 1.18; P = 0.007). In participants with higher sodium intake (median ≥4,102mg/day), a significant association of lnARR with hypertension remained (HR = 1.25; P = 0.009), whereas no significant association was observed in participants with lower sodium intake (P = 0.18). Participants who developed hypertension had significantly lower PRA than those who did not (P = 0.003), despite no differences in PAC (P = 0.91).

CONCLUSIONS

These results raise the hypothesis that relative aldosterone excess may have a deleterious effect on the development of hypertension by contributing to salt/volume-related hypertension.

Determinants of plasma renin activity: role of a human renin gene variant as a genetic factor

The plasma renin activity (PRA) is affected by a number of environmental factors. However, significant heritability has been shown for the activity. A hypothesis that a candidate regulatory single-nucleotide polymorphism, C-5312T, of human renin gene should have a significant effect on PRA was elucidated and updating of independent determinants of PRA was attempted. Cross sectional study. Outpatient study. We enrolled consecutive 810 subjects who had consulted our hospitals for lifestyle-related diseases. Genotypes were assayed with genomic DNA for C-5312T. Among the genetic variants, the difference of PRA was evaluated. Monovariate linear regression analysis was performed to test the correlation between PRA and clinical variables. Finally, stepwise multiple regression analysis was performed to evaluate the independent determinants. On comparing 2 genotype groups, CC/CT and T allele homozygote, the geometric means of PRA were 0.778 and 0.941 ng/ml/h, respectively (F = 5.992, P = 0.015). Monovariate linear regression analysis revealed that a number of variables have a significant correlation with the activity, including urinary salt excretion. A stepwise multivariate regression analysis revealed that renin C-5312T variant (TT) is one of the independent determinants of PRA. Thus, for the first time, a human renin gene variant was associated with a significant increase in PRA as a genetic factor and the independent determinants for the activity were updated including genetic factor.

Plasma renin activity and the aldosterone-to-renin ratio are associated with the development of chronic kidney disease: the Ohasama Study

BACKGROUND

The aldosterone-to-renin ratio (ARR) is used to screen for primary aldosteronism and could be an index for salt sensitivity. The association between ARR and the development of chronic kidney disease (CKD) is completely unknown.

METHOD

A longitudinal observational study involving 689 participants from a general Japanese population (mean age 58.2 years; 68.5% women) who did not have CKD and were not receiving antihypertensive medication at baseline was conducted. The estimated glomerular filtration rate (eGFR) was calculated from serum creatinine levels, and CKD was defined as eGFR less than 60 ml/min per 1.73 m(2) and/or dipstick-positive proteinuria. The associations of baseline plasma renin activity (PRA), plasma aldosterone concentration, and ARR with the development of CKD were examined using Cox proportional hazard regression analysis adjusted for sex, age, BMI, smoking, drinking, history of hypercholesterolemia, diabetes mellitus, and cardiovascular disease, SBP, and baseline eGFR.

RESULTS

During a mean 9.1-year follow-up, 118 participants developed CKD. A 1 standard deviation increment in the natural log-transformed (ln) ARR was positively associated with the incidence of CKD (hazard ratio 1.29, P = 0.012). LnPRA showed an inverse association (hazard ratio 0.76, P = 0.007). Meanwhile, plasma aldosterone concentration was not associated with CKD. Individuals who developed CKD had significantly lower baseline PRA (0.97 vs. 1.14 ng/ml per h; P = 0.03) and higher baseline ARR levels [66.6 vs. 56.8 (pg/ml)/(ng/ml per h); P = 0.02] than those who did not.

CONCLUSIONS

Lower PRA and higher ARR were associated with the development of CKD in a general population, suggesting that they are independent predictors of CKD.

Aldosterone-to-renin ratio as a predictor of stroke under conditions of high sodium intake: the Ohasama study

BACKGROUND

Aldosterone is thought to have deleterious effects on the cardiovascular system. The aldosterone-to-renin ratio (ARR) is more reproducible than aldosterone levels alone and could be an index for inappropriate aldosterone secretion or activity. We previously reported the apparent relation between ARR and hypertension in subjects with high sodium intake. This prospective study investigated the risk of ARR for a first stroke in a general population stratified by sodium intake.

METHODS

We obtained plasma renin activity (PRA) and plasma aldosterone concentrations (PAC) for 883 participants aged ≥ 35 years not receiving antihypertensive treatment in the general population of Ohasama (mean age: 59.0 ± 11.3 years; 65.6% women).

RESULTS

Over a mean of 10.9 follow-up years, 45 strokes occurred. The median PRA, PAC, and ARR were 1.2 ng/ml/h, 6.4 ng/dl, and 5.3 ng/dl per ng/ml/h, respectively. Using Cox regression, we computed hazard ratios adjusted for sex, age, body mass index (BMI), and systolic blood pressure. No association between logARR and stroke was observed in subjects overall. However, in subjects with high sodium intake (≥ median of 4,058 mg/day (salt equivalent, 10.5 g/day)), each 1 s.d. increase in logARR was associated with an increased hazard ratio for stroke (hazard ratio: 1.49, P = 0.04). No significant association was observed in subjects with low sodium intake (P = 0.7). When we repeated all the analyses using logPRA or logPAC, no significant associations were found.

CONCLUSION

These results suggest that high ARR, that is, relative aldosterone excess, is a predictor for stroke under conditions of high sodium intake.