The effect of age, sex and BMI on the aldosterone-to-renin ratio in essential hypertensive individuals

OBJECTIVE

The aldosterone-to-renin ratio (ARR) is widely used as a screening test for primary aldosteronism, but its determinants in patients with essential hypertension are not fully known. The purpose of the present investigation is to identify the impact of age, sex and BMI on renin, aldosterone and the ARR when measured under strict, standardized conditions in hypertensive patients without primary aldosteronism.

METHODS

We analysed the data of 423 consecutive hypertensive patients with no concomitant cardiac or renal disorders from two different hospitals (Rotterdam and Maastricht) who had been referred for evaluation of their hypertension. Those who were diagnosed with secondary causes of hypertension, including primary aldosteronism, were excluded from analysis. Patients who used oral contraceptives or had hormonal replacement therapy were excluded as well. Plasma aldosterone concentration (PAC), active plasma renin concentration (APRC) and the ARR were measured under standardized conditions. All measurements were taken in the supine position at 10.00 h in the morning, with one subgroup of patients adhering to a sodium-restricted diet (55 mmol/day) for no less than 3 weeks, and the other subgroup maintaining an ad libitum diet. In those who were receiving antihypertensive treatment, all medications were discontinued at least 3 weeks before testing.

RESULTS

In neither group did aldosterone correlate with age. Renin, however, was inversely related to age both during low-salt diet ( P  < 0.001) and during ad lib salt intake ( P  = 0.05). This resulted in a significant positive correlation between age and the ARR in both groups. Although on both dietary regimens, PAC and APRC were significantly higher in men when compared with women, the ARR was not significantly different between the two sexes. The age-relationships of renin and the ARR were comparable in men and women on both diets, albeit with greater variability in women. There was an upward trend between BMI and the ARR, which reached statistical significance only in men on low-salt diet. In multivariable regression analysis, age remained the only independent determinant of the ARR.

CONCLUSION

In our essential hypertensive population, the ARR increased significantly with age but was not affected by sex or BMI.

Urinary Sodium Excretion and Salt Intake Are Not Associated With Blood Pressure Variability in a White General Population

Background Salt restriction may lower blood pressure variability (BPV), but previous studies have shown inconsistent results. Therefore, we investigated in an observational study and intervention trial whether urinary sodium excretion and salt intake are associated with 24-hour BPV. Methods and Results We used data from the cross-sectional population-based Maastricht Study (n=2652; 60±8 years; 52% men) and from a randomized crossover trial (n=40; 49±11 years; 33% men). In the observational study, we measured 24-hour urinary sodium excretion and 24-hour BPV and performed linear regression adjusted for age, sex, mean blood pressure, lifestyle, and cardiovascular risk factors. In the intervention study, participants adhered to a 7-day low- and high-salt diet (50 and 250 mmol NaCl/24 h) with a washout period of 14 days, 24-hour BPV was measured during each diet. We used linear mixed models adjusted for order of diet, mean blood pressure, and body mass index. In the observational study, 24-hour urinary sodium excretion was not associated with 24-hour systolic or diastolic BPV (β, per 1 g/24 h urinary sodium excretion: 0.05 mm Hg [95% CI, -0.02 to 0.11] and 0.04 mm Hg [95% CI, -0.01 to 0.09], respectively). In the intervention trial, mean difference in 24-hour systolic and diastolic BPV between the low- and high-salt diet was not statistically significantly different (0.62 mm Hg [95% CI, -0.10 to 1.35] and 0.04 mm Hg [95% CI, -0.54 to 0.63], respectively). Conclusions Urinary sodium excretion and salt intake are not independently associated with 24-hour BPV. These findings suggest that salt restriction is not an effective strategy to lower BPV in the White general population. Registration URL: https://clinicaltrials.gov/ct2/show/NCT02068781.

Variability of aldosterone, renin and the aldosterone-to-renin ratio in hypertensive patients without primary aldosteronism

OBJECTIVES

The aldosterone-to-renin ratio (ARR) is commonly used in the screening of primary aldosteronism. However, limited information is available with regard to the intra-patient variability in this ratio. Our objective is to determine whether ARR measurements are reliably consistent over both the short- and long-term.

METHODS

We assessed the short-term variability of the aldosterone-to-renin ratio in 116 unmedicated, essential hypertensive participants who had two blood samples taken in the morning of the same day for measurement of aldosterone and active plasma renin concentration. Long-term variability was studied in 22 unmedicated, essential hypertensive participants who had two blood samples taken approximately 1 year apart. All samples were taken under highly standardized conditions.

RESULTS

Our data show that renin, aldosterone and the aldosterone-to-renin ratio show marked variations, both when measured on the same day and when assessed at a longer interval. The ARR becomes increasingly variable as its mean value increases. Its degree of variability is similar in both the short-term and the long-term.

CONCLUSIONS

Based on our findings, we conclude that the aldosterone-to-renin has acceptable short-term variability in the lower ranges, but increasingly dubious reliability as aldosterone-to-renin values rise. Thus, in a clinical context, great caution should be taken in interpreting point-measurements of moderate to high aldosterone-to-renin ratio values.

Renal Clearance of Fibroblast Growth Factor-23 (FGF23) and its Fragments in Humans

Relative abundance of fibroblast growth factor-23 (FGF23) measured by the C-terminal (cFGF23, which measures both intact FGF23 and C-terminal fragments) versus intact (iFGF23, measures only intact hormone) assays varies by kidney function in humans. Differential kidney clearance may explain this finding. We measured cFGF23 and iFGF23 in the aorta and bilateral renal veins of 162 patients with essential hypertension undergoing renal angiography. Using multivariable linear regression, we examined factors associated with aorta to renal vein reduction of FGF23 using both assays. Similar parameters and with addition of urine concentrations of cFGF23 and iFGF23 were measured in six Wistar rats. Mean ± standard deviation (SD) age was 54 ± 12 years, 54% were women, and mean creatinine clearance was 72 ± 48 mL/min/100 g. The human kidney reduced the concentrations of both cFGF23 (16% ± 12%) and iFGF23 (21% ± 16%), but reduction was higher for iFGF23. Greater kidney creatinine and PTH reductions were each independently associated with greater reductions of both cFGF23 and iFGF23. The greater kidney reduction of iFGF23 compared to cFGF23 appeared stable and consistent across the range of creatinine clearance evaluated. Kidney clearance was similar, and urine concentrations of both assays were low in the rat models, suggesting kidney metabolism of both cFGF23 and iFGF23. Renal reduction of iFGF23 is higher than that of creatinine and cFGF23. Our data suggest that FGF23 is metabolized by the kidney. However, the major cell types involved in metabolization of FGF23 requires future study. Kidney clearance of FGF23 does not explain differences in C-terminal and intact moieties across the range of kidney function. © 2022 American Society for Bone and Mineral Research (ASBMR).

Night shifts and hypertension

Shift workers may develop increased blood pressure.

Control in the Hospital by Extensive Clinical rules for Unplanned hospitalizations in older Patients (CHECkUP); study design of a multicentre randomized study

Background

Due to ageing of the population the incidence of multimorbidity and polypharmacy is rising. Polypharmacy is a risk factor for medication-related (re)admission and therefore places a significant burden on the healthcare system. The reported incidence of medication-related (re)admissions varies widely due to the lack of a clear definition. Some medications are known to increase the risk for medication-related admission and are therefore published in the triggerlist of the Dutch guideline for Polypharmacy in older patients. Different interventions to support medication optimization have been studied to reduce medication-related (re)admissions. However, the optimal template of medication optimization is still unknown, which contributes to the large heterogeneity of their effect on hospital readmissions. Therefore, we implemented a clinical decision support system (CDSS) to optimize medication lists and investigate whether continuous use of a CDSS reduces the number of hospital readmissions in older patients, who previously have had an unplanned probably medication-related hospitalization.

Methods

The CHECkUP study is a multicentre randomized study in older (≥60 years) patients with an unplanned hospitalization, polypharmacy (≥5 medications) and using at least two medications from the triggerlist, from Zuyderland Medical Centre and Maastricht University Medical Centre+ in the Netherlands. Patients will be randomized. The intervention consists of continuous (weekly) use of a CDSS, which generates a Medication Optimization Profile, which will be sent to the patient’s general practitioner and pharmacist. The control group will receive standard care. The primary outcome is hospital readmission within 1 year after study inclusion. Secondary outcomes are one-year mortality, number of emergency department visits, nursing home admissions, time to hospital readmissions and we will evaluate the quality of life and socio-economic status.

Discussion

This study is expected to add evidence on the knowledge of medication optimization and whether use of a continuous CDSS ameliorates the risk of adverse outcomes in older patients, already at an increased risk of medication-related (re)admission. To our knowledge, this is the first large study, providing one-year follow-up data and reporting not only on quality of care indicators, but also on quality-of-life.

Trial registration

The trial was registered in the Netherlands Trial Register on October 14, 2018, identifier: NL7449 (NTR7691). https://www.trialregister.nl/trial/7449.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02723-8.

The effect of medication on the aldosterone-to-renin ratio. A critical review of the literature

The aldosterone-to-renin ratio (ARR) is a common screening test for primary aldosteronism in hypertensives. However, patients often use medications that could confound the ARR and, thereby, reduce the interpretability of the test. Since it is not always feasible to stop such medication, several drugs that are supposedly neutral with respect to the ARR have been recommended as alternative treatment. The objective of the present review is to explore whether sufficient evidence exists to justify the recommendations. To this end, we performed a systematic PubMed and Cochrane literature search regarding medications that may influence the ARR. Our review revealed that many commonly prescribed antihypertensives seem to have significant effects on renin, aldosterone, and resulting ARR values. However, the magnitude of these effects is poorly quantifiable with the present level of research. We conclude that several medications can affect the ARR. Not taking this into account could lead to misinterpretation of the ARR. Therefore, standardization of the medications used during ARR measurement is advisable for a reliable and accurate interpretation. Further research is needed to ascertain how to best optimize these medications.

Nutritional assessment and the role of preexisting inflammation with a bearing on COVID-19

 Although there is consensus in the European, American, Latin-American, and Asiatic nutrition and metabolic scientific societies regarding the definition of malnutrition, this definition has not been operationalized. This means that in different countries, the risk of malnutrition on outcome cannot be adequately determined or predicted. In patients with inflammatory activity, the preexistent nutritional status is an important predictor of outcome. Malnutrition is characterized by three crucial elements: undernutrition, inflammation, and diminished function. Malnutrition in our countries as well as in countries with famine almost always is caused by varying degrees of deficient nutritional intake in combination with disease or other damaging inflammatory causes of varying severity. The female genome appears to be better equipped to survive intercurrent trauma or illness than the male one, which impacts on longevity and the ability to overcome certain infections like COVID-19 at higher ages.

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.

Intact and C-Terminal FGF23 Assays-Do Kidney Function, Inflammation, and Low Iron Influence Relationships With Outcomes?

CONTEXT

Higher fibroblast growth factor-23 (FGF23) concentrations are associated with heart failure and mortality in diverse populations, but the strengths of associations differ markedly depending up on which assay is used.

OBJECTIVE

We sought to evaluate whether iron deficiency, inflammation, or kidney function account for differences in the strengths of associations between these 2 FGF23 assays with clinical outcomes.

DESIGN

Case cohort study from the Cardiovascular Health Study.

SETTING

A total of 844 community-dwelling individuals aged 65 years or older with and without chronic kidney disease were followed for 10 years.

OUTCOMES

Outcomes included death, incident heart failure (HF), and incident myocardial infarction (MI). Exposure was baseline intact and C-terminal FGF23. Using modified Cox models, adjusting sequentially we tested whether observed associations of each assay with outcomes were attenuated by iron status, inflammation, kidney function, or their combinations.

RESULTS

FGF23 measured by either assay was associated with mortality in unadjusted analysis (intact FGF23 hazard ratio [HR] per 2-fold higher 1.45; 95% CI, 1.25-1.68; C-terminal FGF23 HR 1.38; 95% CI, 1.26-1.50). Adjustment for kidney function completely attenuated associations of intact FGF23 with mortality (HR 1.00; 95% CI, 0.85-1.17), but had much less influence on the association of C-terminal FGF23, for which results remained significant after adjustment (HR 1.15; 95% CI, 1.04-1.28). Attenuation was much less with adjustment for iron status or inflammation. Results were similar for the HF end point. Neither C-terminal or intact FGF23 was associated with MI risk.

CONCLUSIONS

The relationship of FGF23 with clinical end points is markedly different depending on the type of FGF23 assay used. The associations of biologically active FGF23 with clinical end points may be confounded by kidney disease, and thus much weaker than previously thought.

Rationale and design of the PRAETORIAN-COVID trial: A double-blind, placebo-controlled randomized clinical trial with valsartan for PRevention of Acute rEspiraTORy dIstress syndrome in hospitAlized patieNts with SARS-COV-2 Infection Disease

There is much debate on the use of angiotensin receptor blockers (ARBs) in severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)-infected patients. Although it has been suggested that ARBs might lead to a higher susceptibility and severity of SARS-CoV-2 infection, experimental data suggest that ARBs may reduce acute lung injury via blocking angiotensin-II-mediated pulmonary permeability, inflammation, and fibrosis. However, despite these hypotheses, specific studies on ARBs in SARS-CoV-2 patients are lacking. METHODS: The PRAETORIAN-COVID trial is a multicenter, double-blind, placebo-controlled 1:1 randomized clinical trial in adult hospitalized SARS-CoV-2-infected patients (n = 651). The primary aim is to investigate the effect of the ARB valsartan compared to placebo on the composite end point of admission to an intensive care unit, mechanical ventilation, or death within 14 days of randomization. The active-treatment arm will receive valsartan in a dosage titrated to blood pressure up to a maximum of 160 mg bid, and the placebo arm will receive matching placebo. Treatment duration will be 14 days, or until the occurrence of the primary end point or until hospital discharge, if either of these occurs within 14 days. The trial is registered at clinicaltrials.gov (NCT04335786, 2020). SUMMARY: The PRAETORIAN-COVID trial is a double-blind, placebo-controlled 1:1 randomized trial to assess the effect of valsartan compared to placebo on the occurrence of ICU admission, mechanical ventilation, and death in hospitalized SARS-CoV-2-infected patients. The results of this study might impact the treatment of SARS-CoV-2 patients globally.

Concerns of older patients and their caregivers in the emergency department

Background

Older emergency department (ED) patients often have complex problems and severe illnesses with a high risk of adverse outcomes. It is likely that these older patients are troubled with concerns, which might reflect their preferences and needs concerning medical care. However, data regarding this topic are lacking.

Methods

This study is a sub study of a prospective, multicenter, observational cohort study among older medical ED patients (≥65 years). Patients or their caregivers were asked about their illness-related concerns during the first stage of the ED visit using a questionnaire. All concerns were categorized into 10 categories, and differences between patients and caregivers, and between age groups were analyzed. Odds Ratios were calculated to determine the association of the concerns for different adverse outcomes.

Results

Most of the 594 included patients (or their caregivers) were concerned (88%) about some aspects of their illness or their need for medical care. The most often reported concerns were about the severity of disease (43.6%), functional decline (9.4%) and dying (5.6%). Caregivers were more frequently concerned than patients (p<0.001) especially regarding the severity of disease (50.5 vs 39.6%, p = 0.016) and cognitive decline (10.8 vs. 0.3%, p <0.001). We found no difference between age groups. The concern about dying was associated with 30-day mortality (OR 2.89; 95%CI: 1.24–6.70) and the composite endpoint (intensive- or medium care admission, length of hospital stay >7 days, loss of independent living and unplanned readmission within 30 days) (OR 2.32; 95%CI: 1.12–4.82). In addition, unspecified concerns were associated with mortality (OR 1.88; 95%CI: 1.09–3.22).

Conclusion

The majority of older patients and especially their caregivers are concerned about their medical condition or need for medical care when they visit the ED. These concerns are associated with adverse outcomes and most likely reflect their needs regarding medical care. More attention should be paid to these concerns because they may offer opportunities to reduce anxiety and provide care that is adjusted to their needs.

Trial registration

This study was registered on clinicalTriagls.gov (NCT02946398).

A new simplified model for predicting 30-day mortality in older medical emergency department patients: The rise up score

BACKGROUND/OBJECTIVES

Currently, accurate clinical models that predict short-term mortality in older (≥ 65 years) emergency department (ED) patients are lacking. We aimed to develop and validate a prediction model for 30-day mortality in older ED patients that is easy to apply using variables that are readily available and reliably retrievable during the short phase of an ED stay.

METHODS

Prospective multi-centre cohort study in older medical ED patients. The model was derived through logistic regression analyses, externally validated and compared with other well-known prediction models (Identification of Seniors at Risk (ISAR), ISAR-Hospitalised Patients, Acute Physiology and Chronic Health Evaluation II (APACHE II) and Modified Early Warning Score (MEWS)).

RESULTS

Within 30 days after presentation, 66 (10.9%) of 603 patients in the derivation cohort and 105 (13.3%) of 792 patients in the validation cohort died. The newly developed model included 6 predictors: age, ≥2 abnormal vital signs, serum albumin, blood urea nitrogen, lactate dehydrogenase, and bilirubin. The discriminatory value of the model for mortality was very good with an AUC of 0.84 in the derivation and 0.83 in the validation cohort. The final model was excellently calibrated (Hosmer-Lemeshow p-value 0.89). The discriminatory value of the model was significantly higher than that of the four risk stratification scores (highest AUC of 0.69 for ISAR score, p-value 0.007).

CONCLUSION

We developed and externally validated an accurate and simplified prediction model for 30-day mortality in older ED patients. This model may be useful to identify patients at risk of short-term mortality and to apply personalised medical care.

Glucocorticoids affect metabolic but not muscle microvascular insulin sensitivity following high versus low salt intake

BACKGROUNDSalt-sensitive hypertension is often accompanied by insulin resistance in obese individuals, but the underlying mechanisms are obscure. Microvascular function is known to affect both salt sensitivity of blood pressure and metabolic insulin sensitivity. We hypothesized that excessive salt intake increases blood pressure and decreases insulin-mediated glucose disposal, at least in part by impairing insulin-mediated muscle microvascular recruitment (IMMR).METHODSIn 20 lean and 20 abdominally obese individuals, we assessed mean arterial pressure (MAP; 24-hour ambulatory blood pressure measurements), insulin-mediated whole-body glucose disposal (M/I value; hyperinsulinemic-euglycemic clamp technique), IMMR (contrast-enhanced ultrasound), osmolyte and water balance, and excretion of mineralocorticoids, glucocorticoids, and amino and organic acids after a low- and high-salt diet during 7 days in a randomized, double-blind, crossover design.RESULTSOn a low-, as compared with a high-salt, intake, MAP was lower, M/I value was lower, and IMMR was greater in both lean and abdominally obese individuals. In addition, natural logarithm IMMR was inversely associated with MAP in lean participants on a low-salt diet only. On a high-salt diet, free water clearance decreased, and excretion of glucocorticoids and of amino acids involved in the urea cycle increased.CONCLUSIONOur findings imply that hemodynamic and metabolic changes resulting from alterations in salt intake are not necessarily associated. Moreover, they are consistent with the concept that a high-salt intake increases muscle glucose uptake as a response to high salt-induced, glucocorticoid-driven muscle catabolism to stimulate urea production and thereby renal water conservation.TRIAL REGISTRATIONClinicalTrials.gov, NCT02068781.

Venous carbon dioxide embolism during laparoscopic cholecystectomy a literature review

Laparoscopy has become the procedure of choice for routine gallbladder removal. A serious complication of this technique is the occurrence of gas emboli due to insufflation. It is associated with a high mortality rate of around 28%. The present systematic review intends to provide more insight into causes, symptoms and risk factors for this specific complication and to explore which measures should be taken to treat and prevent it. The Cochrane library and Pubmed were used as sources. Articles and their references were selected when they were related to the subject in sufficient detail. The course of this complication can vary from asymptomatic up to impairment of normal flow through the right ventricle (RV) or pulmonary artery, potentially leading to acute heart failure. The severity depends on the amount of gas, the rate of accumulation and the ability to remove the gas bubbles. It is difficult to estimate the true incidence of venous gas embolism during laparoscopic cholecystectomy as there are various diagnostic tools, each with different sensitivity. Precautions that need to be taken are: correct positioning of the needle, low insufflation pressure, low insufflation speed, screening for hypovolemia, Trendelenburg positioning, availability of intervention equipment at operation table, no placement of venous catheters during inspiration and catheter removing during expiration. Physicians need to be more aware of this harmful complication and the preventative measurements that need to be taken. As there are virtually no prospective data, future studies are needed to gain more knowledge on gas emboli during laparoscopic cholecystectomy.

Hypertensive organ damage predicts future cognitive performance: A 9-year follow-up study in patients with hypertension

Hypertension is associated with cognitive deficits, probably caused by cerebral small vessel disease. The authors examined whether additional presence of cardiac and renal organ damages, and their combined presence, are associated with future cognitive performance. In 78 patients with essential hypertension (mean age 51.2 ± 12.0 years), brain damage was determined by MRI features, cardiac damage by left ventricular mass index (LVMI), and renal damage by estimated glomerular filtration rate (eGFR) and albuminuria. At 9‐year follow‐up, neuropsychological assessment was performed. LVMI was associated with future lower cognition (P = 0.032), independent of age, sex, premorbid cognition, and brain damage, but eGFR and albuminuria were not. The presence of 2 or 3 types of organ damage compared to none was associated with future lower cognition. Increasing number of hypertensive organ damages, and cardiac damage independently of brain damage, might indicate a more severe hypertensive disease burden and could help to identify patients at risk of cognitive problems.

Aldosterone Is Not Associated With Metabolic and Microvascular Insulin Sensitivity in Abdominally Obese Men

CONTEXT

Impaired insulin-mediated muscle microvascular recruitment (IMMR) may add to the development of insulin resistance and hypertension. Increased aldosterone levels have been linked to these obesity-related complications in severely to morbidly obese individuals and to impaired microvascular function in experimental studies.

OBJECTIVES

To investigate whether aldosterone levels are associated with IMMR, insulin sensitivity, and blood pressure in lean and moderately abdominally obese men, and to study the effect of weight loss.

DESIGN, SETTING, PARTICIPANTS, INTERVENTION, MAIN OUTCOME MEASURES

In 25 lean and 53 abdominally obese men, 24-hour blood pressure measurement was performed, and aldosterone levels were measured using ultra-performance liquid chromatography tandem mass spectrometry. Insulin sensitivity was assessed by determining whole-body glucose disposal during a hyperinsulinemic clamp. IMMR in forearm skeletal muscle was measured with contrast-enhanced ultrasonography. These assessments were repeated in the abdominally obese men following an 8-week weight loss or weight stable period.

RESULTS

Sodium excretion and aldosterone levels were similar in lean and abdominally obese participants, but sodium excretion was inversely associated with aldosterone concentration only in the lean individuals [lean, β/100 mmol sodium excretion (adjusted for age and urinary potassium excretion) = -0.481 (95% confidence interval, -0.949 to -0.013); abdominally obese, β/100 mmol sodium excretion = -0.081 (95% confidence interval, -0.433 to 0.271); P for interaction = 0.02]. Aldosterone was not associated with IMMR, insulin sensitivity, or blood pressure and was unaffected by weight loss.

CONCLUSION

In moderately abdominally obese men, the inverse relationship between sodium excretion and aldosterone concentration is less than that in lean men but does not translate into higher aldosterone levels. The absolute aldosterone level does not explain differences in microvascular and metabolic insulin sensitivity and blood pressure between lean and moderately abdominally obese men.

Framingham Stroke Risk Profile is related to cerebral small vessel disease progression and lower cognitive performance in patients with hypertension

The Framingham Stroke Risk Profile (FSRP) was developed to predict clinical stroke. We investigated if FSRP is associated with more "silent" effects of cerebrovascular disease, namely progression of cerebral small vessel disease (cSVD)-related brain damage and cognitive performance in hypertensive patients. Ninety patients with essential hypertension underwent a brain MRI scan and FSRP assessment at baseline, and a second brain MRI scan and neuropsychological assessment at 9-year follow-up. We visually rated progression of cSVD-related MRI markers. FSRP was associated with progressive periventricular white matter hyperintensities (P = .017) and new microbleeds (P = .031), but not after correction for the FSRP age component. FSRP was associated with lower overall cognitive performance (P < .001) and this remained significant after correction for the FSRP age component. A vascular risk score might be useful in predicting progression of cSVD-related brain damage or future cognitive performance in hypertensive patients. Age seems to be the most important component in FSRP.

Coronary Tortuosity: A Clue to the Diagnosis of Fibromuscular Dysplasia?

BACKGROUND

Fibromuscular dysplasia (FMD) is a systemic, nonatherosclerotic, noninflammatory vasculopathy that is often overlooked by clinicians. Clinical clues could help in selecting patients for further evaluation for the presence of FMD. Recently, it was observed that tortuosity of the coronary arteries is often present in patients with FMD-related abnormalities of the coronary artery. Therefore, we wondered if the presence of coronary tortuosity might provide a clinical clue to the diagnosis of extracoronary FMD.

CASES

We describe 5 cases of FMD in whom diagnostic studies for FMD were initiated because of the presence of coronary tortuosity. FMD was found in all 5 patients in the renal and/or cervical arteries.

CONCLUSIONS

Our 5 cases suggest that exertional chest pain in the presence of coronary tortuosity may be helpful in selecting patients for further evaluation for the presence of FMD. Further research should focus on the prevalence of FMD among patients with coronary tortuosity and whether the presence of additional clinical clues (such as the presence of hypertension at young age or pulsatile tinnitus) next to coronary tortuosity can predict the risk for FMD in individual patients.

The Link Between Adipose Tissue Renin-Angiotensin-Aldosterone System Signaling and Obesity-Associated Hypertension

Obese individuals frequently develop hypertension, which is for an important part attributable to renin-angiotensin-aldosterone system (RAAS) overactivity. This review summarizes preclinical and clinical evidence on the involvement of dysfunctional adipose tissue in RAAS activation and on the renal, central, and vascular mechanisms linking RAAS components to obesity-associated hypertension.

Sustained Reduction of Blood Pressure With Baroreceptor Activation Therapy: Results of the 6-Year Open Follow-Up

Baroreflex activation therapy is a novel technique for treating patients with resistant hypertension. Although short-term studies have demonstrated that it lowers blood pressure, long-term results have not yet been reported. The aim of the present study is to assess the long-term efficacy and safety of baroreflex activation therapy. Long-term follow-up data were analyzed from all patients who had been included in 1 of the 3 trials that focused on treatment-resistant hypertensive patients. Altogether, 383 patients were available for analysis: 143 of these had completed 5 years of follow-up and 48 patients had completed 6 years of follow-up. In the entire cohort, office systolic blood pressure fell from 179±24 mm Hg to 144±28 mm Hg (P<0.0001), whereas office diastolic pressure dropped from 103±16 mm Hg to 85±18 mm Hg (P<0.0001). Heart rate fell from 74±15 beats per minute to 71±13 beats per minute (P<0.02). The effect of baroreflex activation therapy is greater than average in patients with signs of heart failure and less than average in patients with isolated systolic hypertension. In ≈25% of patients, it was possible to reduce the number of medications from a median of 6 to a median of 3. Temporary side effects, related to either the surgical procedure or the cardiovascular instability, do occur, but they do not require specific measures and resolve over time.After a follow-up of 6 years, baroreflex activation therapy maintains its efficacy for persistent reduction of office blood pressure in patients with resistant hypertension without major safety issues.

The effects of missed doses of amlodipine and losartan on blood pressure in older hypertensive patients

This randomized, double-blind, parallel-group, multicenter study compared the efficacy of amlodipine and losartan in an older hypertensive population, focusing on therapeutic coverage in the case of missed doses. Following a 4-week, single-blind, placebo washout period, 211 patients were randomly assigned to receive either 5 mg of amlodipine once daily or 50 mg of losartan once daily. Doses were doubled after 6 weeks of treatment if the diastolic blood pressure exceeded 90 mm Hg. After the 12-week treatment period, patients received the placebo for 2 days (drug holiday) to simulate two missed doses of antihypertensive medication. Twenty-four-hour ambulatory blood pressure monitoring was conducted at the end of the placebo washout period (baseline), upon completion of the 12-week treatment period (steady state), and after the 2-day drug holiday. Amlodipine was more effective than losartan in reducing patients' 24-h ambulatory blood pressure at the steady-state sampling time. The increases in 24-h blood pressure during the drug holiday averaged 6±2/2±1 mm Hg (P<0.0001) in the amlodipine group and 3±2/2±1 mm Hg (P<0.0001) in the losartan group. The rise in systolic pressure was greater in patients on amlodipine than in those on losartan (P<0.0001). For diastolic pressure, the changes did not differ. Owing to the lower pressure during treatment, patients in the amlodipine group remained at a significantly lower blood pressure level after the 2-day drug holiday. Amlodipine was more effective than losartan in lowering blood pressure and in maintaining blood pressure control after two missed doses, and the difference was most significant for systolic blood pressure.

CD4+CD28null T Cells are related to previous cytomegalovirus infection but not to accelerated atherosclerosis in ANCA-associated vasculitis

Previous studies have suggested an increased risk for cardiovascular events in antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). We analyzed the presence of atherosclerotic damage in patients with AAV in relation to the presence of CD4⁺CD28^null T cells and antibodies against cytomegalovirus (CMV) and human Heat-Shock Protein 60 (hHSP60). In this cross-sectional study, patients with inactive AAV were compared with healthy controls (HC). Carotid intima-media thickness (IMT) and aortic pulse-wave velocity (PWV) were measured. In addition, CD4⁺CD28^null T cells, anti-CMV, and anti-hHSP60 levels were determined. Forty patients with AAV were included. Patients’ spouses were recruited as HC (N = 38). CD4⁺CD28^null T cells are present in patients with AAV in a higher percentage (median 3.1, range 0.01–85) than in HC (0.28, 0–36, P < 0.0001). No significant difference in IMT (mm) between patients and controls was detected (mean 0.77 ± standard deviation 0.15 and 0.73 ± 0.11, respectively, P = 0.20). PWV standardized for MAP was increased in AAV patients (9.80 ± 2.50 m/s, compared to 8.72 ± 1.68 in HC, P = 0.04). There was a strong association between a previous CMV infection and the presence and percentage of CD4⁺CD28^null T cells (0.33 vs 13.8, P < 0.001). There was no relationship between CD4⁺CD28^null T cells and/or a previous CMV infection and IMT or PWV. There was no relation between anti-hHSP60 and CD4⁺CD28^null T cells. Increased PWV values suggest atherosclerotic damage in patients with AAV. Plaque size, as determined by IMT, did not differ. CD4⁺CD28^null T cells are increased in AAV and related to the previous CMV infection.

Dementia risk in renal dysfunction: A systematic review and meta-analysis of prospective studies

OBJECTIVE

Renal dysfunction has been linked with increased risk for cognitive impairment and dementia, but studies are conflicting. For that reason, the aim of the present systematic review and meta-analysis is to summarize the best available evidence on the prospective association between potential markers of renal dysfunction and development of cognitive impairment or dementia.

METHODS

Medline, Embase, and Cochrane Database of Systematic Reviews were searched for potential publications until August 1, 2016. Studies were eligible if they fulfilled the following criteria: population-based study, prospective design, ≥100 participants, aged ≥45 years, ≥1 year follow-up, and cognition/dementia outcomes. Where appropriate, random effects meta-analyses were conducted yielding pooled odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Twenty-two out of 8,494 abstracts fulfilled the eligibility criteria. Sufficient evidence was found for albuminuria, mixed results for estimated glomerular filtration rate (eGFR), insufficient support for cystatin C, and tentative evidence for serum creatinine and creatinine clearance. Meta-analyses of 5 studies representing 27,805 persons showed a 35% increased risk of cognitive impairment or dementia in those with albuminuria (OR 1.35, 95% CI 1.06-1.73, p = 0.015), whereas eGFR <60 mL/min/1.73 m² showed no significant association (OR 1.28, 95% CI 0.99-1.65, p = 0.063). No meta-analyses could be done for serum creatinine, creatinine clearance, or cystatin C.

CONCLUSIONS

The overall evidence for an association between renal dysfunction and cognitive impairment or dementia is modest. Evidence suggests that albuminuria is associated with higher odds of developing cognitive impairment or dementia.

Aldosterone-Renin Ratio and Side-Selective Renal Perfusion in Essential Hypertension

BACKGROUND

The decrease in kidney perfusion as often observed in hypertensive individuals does not necessarily occur in a symmetrical fashion, thereby potentially introducing left-right differences in response to vasoactive agents. Increased aldosterone levels have been associated with reduced renal perfusion in normotensive and hypertensive individuals, but it is unknown whether both kidneys are equally affected in this respect and how angiotensin II is involved in this relationship. Therefore, our aim was to investigate the association of both aldosterone and the aldosterone-renin ratio with side-selective renal blood flow in essential hypertension.

METHODS

We studied 146 essential hypertensive patients with patent renal arteries who had undergone renal angiography for exclusion of renal artery stenosis. Prior to contrast administration, blood samples were drawn for the determination of renin and aldosterone levels, and side-selective renal blood flow was measured using the 133Xenon washout technique.

RESULTS

Left mean renal blood flow (MRBF) was significantly lower than right MRBF (227±74 vs. 250±76mL * min-1 * 100g kidney-1, P = 0.01). We could not demonstrate a correlation of ln aldosterone or ln renin with left or right kidney perfusion. Ln aldosterone-renin ratio (ARR), however, was inversely and independently associated with left MRBF (β = -13.993, P = 0.02; fully adjusted model) but not with right MRBF.

CONCLUSIONS

A higher ARR corresponds to reduced perfusion of the left kidney, yet is not associated with right kidney perfusion. Especially under circumstances of diminished right renal blood flow, this may affect blood pressure and kidney function.

Effect of increased protein intake on renal acid load and renal hemodynamic responses

Increased protein intake versus maltodextrin intake for 4 weeks lowers blood pressure. Concerns exist that high‐protein diets reduce renal function. Effects of acute and 4‐week protein intake versus maltodextrin intake on renal acid load, glomerular filtration rate and related parameters were compared in this study. Seventy‐nine overweight individuals with untreated elevated blood pressure and normal kidney function were randomized to consume a mix of protein isolates (60 g/day) or maltodextrin (60 g/day) for 4 weeks in energy balance. Twenty‐four‐hour urinary potential renal acid load (uPRAL) was compared between groups. A subgroup (maltodextrin N = 27, protein mix N = 25) participated in extra test days investigating fasting levels and postprandial effects of meals supplemented with a moderate protein‐ or maltodextrin‐load on glomerular filtration rate, effective renal plasma flow, plasma renin, aldosterone, pH, and bicarbonate. uPRAL was significantly higher in the protein group after 4 weeks (P ≤ 0.001). Postprandial filtration fraction decreased further after the protein‐supplemented breakfast than after the maltodextrin‐supplemented breakfast after 4 weeks of supplementation (P ≤ 0.001). Fasting and postprandial levels of glomerular filtration rate, effective renal plasma flow, renin, aldosterone, angiotensin‐converting enzyme, pH and bicarbonate did not differ between groups. In conclusion, 4 weeks on an increased protein diet (25% of energy intake) increased renal acid load, but did not affect renal function. Postprandial changes, except for filtration fraction, also did not differ between groups. These data suggest that a moderate increase in protein intake by consumption of a protein mix for 4 weeks causes no (undesirable) effects on kidney function in overweight and obese individuals with normal kidney function.

Arterial stiffness and decline of renal function in a primary care population

Arterial stiffness is an important pathophysiological factor linking cardiovascular disease and kidney disease. Controversy exists as to whether arterial stiffness causes renal function decline, or kidney dysfunction leads to stiffening or whether the association is mutual. We aimed to investigate the longitudinal association between arterial stiffness and annual rate of renal function decline. We prospectively investigated in a primary care population whether carotid-femoral pulse wave velocity (PWV) was associated with estimated glomerular filtration rate (eGFR) and annual decline in eGFR in participants aged ⩾40 years without overt kidney disease. Baseline data on PWV and eGFR were available for 587 participants; follow-up measurements with a mean duration of 5.6 years were available for 222 patients. PWV, female gender and mean arterial pressure were independently associated with eGFR at baseline, although age confounded this association. More importantly, baseline PWV, age and eGFR were independent predictors of renal function decline. Stratification for age showed that the effect of PWV on rate of eGFR decline was amplified with advancing age. On the other hand, baseline eGFR did not determine annual change in PWV, suggesting a unidirectional association between arterial stiffness and eGFR. Arterial stiffness amplifies age-related renal function decline, suggesting that arterial stiffness plays a causal role in the development of renal damage, at least at later stages of age-related renal function decline, possibly through impaired renal autoregulation and increased arterial blood pressure pulsatility.

Formerly Preeclamptic Women With a Subnormal Plasma Volume Are Unable to Maintain a Rise in Stroke Volume During Moderate Exercise

INTRODUCTION

In formerly preeclamptic women with a low plasma volume, the recurrence rate of preeclampsia is higher than in women with a normal prepregnant plasma volume. In a recent study, we demonstrated that the low plasma volume subgroup also had a subnormal venous capacitance. In the present study, we determined the impact of subnormal plasma volume on the hemodynamic response to moderate exercise.

PATIENTS AND METHODS

We performed this study in the follicular phase of the menstrual cycle, in 31 formerly preeclamptic women with a subnormal plasma volume (low-PV) and eight parous controls. The exercise consisted of 60 minutes of cycling in the supine position at 35% of the individualized maximum capacity. Before, during, and after cycling, we measured the percentage change in heart rate, stroke volume, and cardiac output. Before and after exercise, we measured the effective renal plasma flow (ERPF, para-amino-hippurate [PAH] clearance), glomerular filtration rate (GFR, inulin clearance), circulating levels of alpha-atrial natriuretic peptide (alpha-ANP), and active plasma renin concentration (APRC).

RESULTS

The response to exercise of formerly preeclamptic women with a subnormal plasma volume differed from that in controls by a lack of rise in stroke volume, a smaller rise in cardiac output and alpha-ANP, and a greater fall in GFR. The responses in heart rate, ERPF, and APRC did not differ between the two groups.

CONCLUSION

The response to moderate exercise of formerly preeclamptic women with a subnormal plasma volume differs from that in healthy parous controls with a normal plasma volume and suggests a lower capacity to raise venous return in conditions of a higher demand for systemic flow. The lower capacity to raise venous return in these conditions is associated with more cardiovascular drift. The physiologic consequence is a lower aerobic endurance performance during moderate exercise.

Pre-pregnant Prediction of Recurrent Preeclampsia in Normotensive Thrombophilic Formerly Preeclamptic Women Receiving Prophylactic Antithrombotic Medication

BACKGROUND

Both hemodynamic abnormalities and thrombophilia predispose to pregnancy-associated vascular complications such as fetal growth restriction, stillbirth, preeclampsia, and placental abruption. Antithrombotic treatment may reduce the risk for these events. In this study we tested the hypothesis that in normotensive thrombophilic formerly preeclamptic women certain alterations in hemodynamic function as measured under nonpregnant conditions predict the development of hypertensive disorders and/or fetal growth restriction in the subsequent pregnancy.

METHODS

In 350 nondiabetic formerly preeclamptic women, we measured in the follicular phase of the menstrual cycle at least 5 months postpartum central hemodynamic, metabolic, and hemostatic variables. In the subsequent ongoing pregnancy we determined fetal outcome variables and the incidence of maternal vascular complications. In addition to a normotensive thrombophilic profile, inclusion for final analysis required a subsequent singleton pregnancy, established within 1 year following the pre-pregnant evaluation and ongoing beyond 16 weeks' gestation. As a consequence, 47 normotensive thrombophilic formerly preeclamptic women could be included for final analysis. All formerly preeclamptic participants received aspirin throughout pregnancy. Additionally, those with thrombophilia or hyperhomocysteinemia were treated with low molecular weight heparin and with pyridoxine and folic acid supplementation, respectively.

RESULTS

Among 350 formerly preeclamptic women, 266 (76%) were normotensive and 84 (24%) hypertensive. About half (140/266) of normotensive formerly preeclamptic participants were thrombophilic. One hundred eighteen formerly preeclamptic participants succeeded in establishing an ongoing pregnancy within 1 year. From this subset of formerly preeclamptic women, 47 were normotensive thrombophilic; 23 remained normotensive (THROMB), whereas 24 developed at least gestational hypertension (COMPLITHROMB). Participants in the latter subgroup were more obese than those remaining normotensive. In addition, this former subset of women had a higher vascular resistance index, and a lower plasma volume and cardiac index. With respect to fetal outcome, COMPLITHROMB gave birth to an infant with a lower birth weight relative to THROMB. Preeclampsia with or without the hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome recurred in 26% of the participants in the whole thrombophilic group, in which a low pre-pregnant plasma volume and a raised vascular resistance predisposed for recurrent hypertensive disorders.

CONCLUSION

Pre-pregnant hemodynamic, metabolic, and clotting variables in formerly preeclamptic women can predict hypertension in the subsequent pregnancy.

Angiotensin II Sensitivity in Nonpregnant Formerly Preeclamptic Women and Halthy Parous Contorls

BACKGROUND

In women prone to develop hypertensive complications, vascular reactivity fails to decrease in early pregnancy. Since hypertensive syndromes of pregnancy seem to be superimposed on a preexisting disorder, we tested the hypothesis that in formerly preeclamptic women, as compared to healthy parous controls, circulatory reactivity to angiotensin II is enhanced in the follicular phase of the menstrual cycle.

METHODS

Sixty formerly preeclamptic women were subdivided into a hypertensive (HYPERT, n = 14), a normotensive thrombophilic (THROMB, n = 26), and a normotensive nonthrombophilic (ASYMPT, n = 20) subgroup. In these women and in 11 healthy parous controls we assessed at least 5 months postpartum at day 5 (+/-2) of the menstrual cycle the following variables: body weight, height, plasma volume, reactivity to infused angiotensin II of arterial blood pressure, heart rate, glomerular filtration rate (GFR), effective renal blood flow, and the hormones of the renin-angiotensin-aldosterone (RAAS) axis.

RESULTS

At baseline, THROMB did not differ from controls. In contrast, ASYMPT exhibited slight overweight, reduced plasma volume, and reduced renal blood flow. HYPERT much resembled ASYMPT except for the overweight, renal perfusion, and GFR. Infusion of angiotensin II led to comparable decreases in renal perfusion and filtration, and to increases in blood pressure. However, sensitivity to this substance correlated inversely with relative and absolute sizes of the plasma volume compartment.

CONCLUSION

Circulatory sensitivity to infused angiotensin II is comparable between nonpregnant formerly preeclamptic women and healthy parous controls. However, responsiveness to this agent is enhanced among women with a contracted plasma volume compartment, a condition commonly observed among formerly preeclamptic women.