Prognostic Value of Microalbuminuria During Antihypertensive Treatment in Essential Hypertension

Association between circulatory complement activation and hypertensive renal damage: a case-control study

OBJECTIVE

The aim of this study was to investigate the potential importance of complement system activation, with particular emphasis on the complement alternative pathway (AP), in the pathogenesis of hypertensive renal damage.

METHODS

Serum complement C3, complement Factor H (CFH) and AP activation were assessed in 66 participants with established essential hypertension with renal damage (RD). Fifty-nine patients with age- and sex-matched essential hypertension without renal damage (NRD) and 58 healthy participants (normal) were selected.

RESULTS

Our study revealed that C3 and AP50 continuously increased from normal to NRD to RD (p < 0.05, respectively), while CFH was significantly lower than that in NRD and healthy participants (p < 0.05, respectively). After multifactorial logistic regression analysis corrected for confounders, elevated serum C3 (p = 0.001) and decreased CFH (p < 0.001) were found to be independent risk factors for hypertension in healthy participants; elevated serum C3 (p = 0.034), elevated AP50 (p < 0.001), decreased CFH (p < 0.001), increased age (p = 0.011) and increased BMI (p = 0.013) were found to be independent risk factors for the progression of hypertension to hypertensive renal damage; elevated serum C3 (p = 0.017), elevated AP50 (p = 0.023), decreased CFH (p = 0.005) and increased age (p = 0.041) were found to be independent risk factors for the development of hypertensive renal damage in healthy participants.

CONCLUSION

Abnormal activation of complement, particularly complement AP, may be a risk factor for the development and progression of hypertensive renal damage.

High miR-126-3p levels associated with cardiovascular events in a general population

BACKGROUND

Endothelial dysfunction is a forerunner of atherosclerosis, leading to cardiovascular disease, and albuminuria is a marker of endothelial dysfunction. Circulating levels of microRNAs are emerging as potential biomarkers for cardiovascular disease. Here we estimate the predictive value of a plasma microRNAs signature associated with albuminuria in the incidence of cardiovascular events.

METHODS

Plasma microRNAs quantified in hypertensive patients by next generation sequencing were validated in a cohort of patients and controls by real-time quantitative PCR. The microRNAs found to be associated with albuminuria were analysed for their prognostic value in predicting cardiovascular events incidence on a retrospective, population-based study (Hortega Study), using Cox proportional hazard models.

RESULTS

A plasma microRNA profile was identified in the discovery cohort (n = 48) associated with albuminuria and three microRNAs (miR-126-3p, miR-1260b and miR-374a-5p) were confirmed in the validation cohort (n = 98). The microRNA signature discriminates urinary albumin excretion at baseline (n = 1025), and predicts the incidence of cardiovascular events and coronary heart disease and stroke in a general population retrospective study within a 14-year follow-up (n = 926). High miR-126-3p levels were associated with a shorter time free of both cardiovascular events (HR=1.48, (1.36-1.62), p < 0.0001), as well as coronary artery disease and stroke combined (HR=2.49, (2.19-2.83), p < 0.0001).

CONCLUSIONS

An increased plasma microRNAs profile was identified in hypertensive patients with albuminuria. Increased miR-126-3p suggest it may serve as a prognostic marker for cardiovascular events in a long-term general population. Further studies will assess the potential role of miR-126-3p as a guide for the status of endothelial dysfunction.

Hypertension mediated kidney and cardiovascular damage and risk stratification: Redefining concepts

Hypertension mediated organ damage (HMOD) refers to structural or functional changes in arteries or target organs that can be present in long-standing hypertension, but it can be also found in naïve never treated patients. Traditionally, cardiovascular risk is stratified with charts or calculators that tend to underestimate the real cardiovascular risk. The diagnosis of HMOD automatically reclassifies patients to the highest level of cardiovascular risk. Subclinical HMOD can be present already at the diagnosis of hypertension and more than 25% of hypertensives are misclassified with the routine tests recommended by hypertension guidelines. Whether HMOD regression improves cardiovascular outcomes has never been investigated in randomized clinical trials and remains controversial. However, different drugs have been probed with promising results in high cardiovascular risk patients, such as the new antidiabetic or the novel non-steroid mineralocorticoid antagonists. Accordingly, trials have shown that lowering blood pressure reduces cardiovascular events. In this narrative review, we will discuss the role of HMOD in cardiovascular risk stratification, the different types of organ damage, and the evidence available to define whether HMOD can be used as a therapeutic target.

Association of Dipstick Proteinuria with Long-Term Mortality among Patients with Hypertensive Crisis in the Emergency Department

Proteinuria, frequently observed in hypertensive crisis, is a risk factor for cardiovascular and all-cause mortality in patients with hypertension. Here we investigated the association between proteinuria and all-cause mortality in patients with a hypertensive crisis in the emergency department (ED). This retrospective study included patients admitted to the ED of a tertiary referral center between 2016 and 2019 with hypertensive crisis (systolic blood pressure ≥ 180 mmHg or diastolic blood pressure ≥ 110 mmHg); 3599 patients with an assay for proteinuria were included in this study. Proteinuria was defined as a trace or more protein on a urine dipstick test. Proteinuria was present in 1964 (54.6%) of 3599 patients. At 3 years, crude all-cause mortality rates were 10.8% for patients with negative proteinuria, 21.7% for those with trace proteinuria, 29.0% for those with proteinuria (1+), 32.0% for those with proteinuria (2+), and 35.4% for those with proteinuria (≥3+). After adjusting for age, sex, blood pressure, and comorbid conditions, the hazard ratio (95% confidence interval) for dipstick proteinuria was 1.91 (1.53–2.37) for those with trace proteinuria, 2.32 (1.85–2.91) for those with proteinuria (1+), 2.40 (1.86–3.10) for those with proteinuria (2+), and 2.40 (1.78–3.24) for those with proteinuria (≥3+) compared to the reference of negative proteinuria. In patients with hypertensive crisis, dipstick proteinuria was a significant predictor of all-cause mortality, and the risk of all-cause mortality increased in a dose-dependent manner according to its degree. Moreover, even trace proteinuria was associated with an increased risk of mortality. The dipstick urine test could be used as a simple and useful method for risk assessment of all-cause mortality in patients with hypertensive crisis.

The potential role of complement alternative pathway activation in hypertensive renal damage

Hypertensive renal damage is a common secondary kidney disease caused by poor control of blood pressure. Recent evidence has revealed abnormal activation of the complement alternative pathway (AP) in hypertensive patients and animal models and that this phenomenon is related to hypertensive renal damage. Conditions in the setting of hypertension, including high renin concentration, reduced binding of factor H to the glomerular basement membrane, and abnormal local synthesis of complement proteins, potentially promote the AP activation in the kidney. The products of the AP activation promote the phenotypic transition of mesangial cells and tubular cells, attack endothelial cells and recruit immunocytes to worsen hypertensive renal damage. The effects of complement inhibition on hypertensive renal damage are contradictory. Although clinical data support the use of C5 monoclonal antibody in malignant hypertension, pharmacological inhibition in hypertensive animals provides little benefit to kidney function. Therefore, the role of the complement AP in the pathogenesis of hypertensive renal damage and the value of complement inhibition in hypertensive renal damage treatment must be further explored.

Application of omics in hypertension and resistant hypertension

Hypertension is a major modifiable risk factor that affects the global health burden. Despite the availability of multiple antihypertensive drugs, blood pressure is often not optimally controlled. The prevalence of true resistant hypertension in treated hypertensive patients is ~2-20%, and these patients are at higher risk for adverse events and poor clinical outcomes. Therefore, an in-depth dissection of the pathophysiological mechanisms of hypertension and resistant hypertension is needed to identify more effective targets for regulating blood pressure. Omics technologies, such as genomics, transcriptomics, proteomics, metabolomics, and microbiomics, can accurately present the characteristics of organisms at varying molecular levels. Integrative omics can further reveal the network of interactions between molecular levels and provide a complete dynamic view of the organism. In this review, we describe the applications, progress, and challenges of omics technologies in hypertension. Specifically, we discuss the application of omics in resistant hypertension. We believe that omics approaches will produce a better understanding of the pathogenesis of hypertension and resistant hypertension and improve diagnostic and therapeutic strategies, thus increasing rates of blood pressure control and reducing the public health burden of hypertension.

Translational research in nephrology: prognosis

Translational research aims at reducing the gap between the results of studies focused on diagnosis, prognosis and therapy, and every day clinical practice. Prognosis is an essential component of clinical medicine. It aims at estimating the risk of adverse health outcomes in individuals, conditional to their clinical and non-clinical characteristics. There are three fundamental steps in prognostic research: development studies, in which the researcher identifies predictors, assigns the weights to each predictor, and assesses the model’s accuracy through calibration, discrimination and risk reclassification; validation studies, in which investigators test the model’s accuracy in an independent cohort of individuals; and impact studies, in which researchers evaluate whether the use of a prognostic model by clinicians improves their decision-making and patient outcome. This article aims at clarifying how to reduce the disconnection between the promises of prognostic research and the delivery of better individual health.

Exosomal and Plasma Non-Coding RNA Signature Associated with Urinary Albumin Excretion in Hypertension

Non-coding RNA (ncRNA), released into circulation or packaged into exosomes, plays important roles in many biological processes in the kidney. The purpose of the present study is to identify a common ncRNA signature associated with early renal damage and its related molecular pathways. Three individual libraries (plasma and urinary exosomes, and total plasma) were prepared from each hypertensive patient (with or without albuminuria) for ncRNA sequencing analysis. Next, an RNA-based transcriptional regulatory network was constructed. The three RNA biotypes with the greatest number of differentially expressed transcripts were long-ncRNA (lncRNA), microRNA (miRNA) and piwi-interacting RNA (piRNAs). We identified a common 24 ncRNA molecular signature related to hypertension-associated urinary albumin excretion, of which lncRNAs were the most representative. In addition, the transcriptional regulatory network showed five lncRNAs (LINC02614, BAALC-AS1, FAM230B, LOC100505824 and LINC01484) and the miR-301a-3p to play a significant role in network organization and targeting critical pathways regulating filtration barrier integrity and tubule reabsorption. Our study found an ncRNA profile associated with albuminuria, independent of biofluid origin (urine or plasma, circulating or in exosomes) that identifies a handful of potential targets, which may be utilized to study mechanisms of albuminuria and cardiovascular damage.

Cerebral small vessel disease, systemic vascular characteristics and potential therapeutic targets

Introduction: Cerebral small vessel disease (SVD) is prevalent in the elderly population and is associated with increased risk of dementia, stroke and disability. Currently there are no clear targets or strategies for the treatment of cerebral SVD. We set out to identify modifiable vascular treatment targets.

Patients and Methods: 112 participants with and without a history of CVD underwent macrovascular, microvascular and endothelial function tests and an MRI head scan.

Results: Increased carotid intima media thickness and carotid-femoral pulse wave velocity were associated with cerebral WMH (β=1·1 p=0·001 and β=1·66, p<0·0001 respectively). Adjusted cerebral resistance index (p=0·03) and brachial flow mediated dilation time to peak (p=0·001) were associated with the severity of cerebral WMH independent of age and sex. Post occlusive reactive hyperaemia time as a measure of microvascular reactivity was associated with WMH after adjustment for age and sex (p=0·03). Ankle Brachial Pressure Index and urinary albumin excretion rate predicted the severity of cerebral WMH (p=0·02 and 0·01 respectively). Age and hypertension were the most important risk factors for WMH severity (p< 0·0001).

Discussion: In addition to hypertension, microalbuminuria, arterial stiffness, vascular reactivity and cerebrovascular resistance could be potential treatment targets to halt the development or progression of cerebral SVD.

Association of microalbuminuria and adverse outcomes in hypertensive patients: a meta-analysis

BACKGROUND

Studies on the association of microalbuminuria with adverse outcomes in patients with hypertension remain controversial. This meta-analysis aimed to assess the predictive value of microalbuminuria in hypertensive patients.

METHODS

PubMed and Embase databases were comprehensively searched for studies that published from their inceptions to July 10, 2020. Observational studies reporting the association of microalbuminuria (defined as urinary albumin excretion 30 and 300 mg/24 h urine or albumin/creatinine ratio 30-300 mg/g from a spot urine or equivalent value) with all-cause mortality or major adverse cardiovascular events (MACEs) in hypertensive patients were selected.

RESULTS

Nine studies with a total of 19,893 hypertensive patients were included. When compared with those without microalbuminuria, hypertensive patients with microalbuminuria had an increased risk of all-cause mortality (risk ratio [RR] 1.68; 95% confidence interval [CI] 1.46-1.93) and MACEs (RR 1.40; 95% CI 1.22-1.62), respectively. Gender-specific analysis indicated that microalbuminuria was significantly associated with an increased risk of all-cause mortality (RR 1.61; 95% CI 1.17-2.21) in men but not in women (RR 1.18; 95% CI 0.78-1.80).

CONCLUSION

This meta-analysis suggests that microalbuminuria is independently associated with higher risk of MACEs and all-cause mortality in hypertensive patients. Determination of microalbuminuria has potential to improve the risk classification of hypertension.

Urinary- and Plasma-Derived Exosomes Reveal a Distinct MicroRNA Signature Associated With Albuminuria in Hypertension

Urinary albumin excretion (UAE) is a marker of cardiovascular risk and renal damage in hypertension. MicroRNAs (miRNAs) packaged into exosomes function as paracrine effectors in cell communication and the kidney is not exempt. This study aimed to state an exosomal miRNA profile/signature associated to hypertension with increased UAE and the impact of profibrotic TGF-β1 (transforming growth factor β1) on exosomes miRNA release. Therefore, exosomes samples from patients with hypertension with/without UAE were isolated and characterized. Three individual and unique small RNA libraries from each subject were prepared (total plasma, urinary, and plasma-derived exosomes) for next-generation sequencing profiling. Differentially expressed miRNAs were over-represented in Kyoto Encyclopedia of Genes and Genomes pathways, and selected miRNAs were validated by real-time quantitative polymerase chain reaction in a confirmation cohort. Thus, a signature of 29 dysregulated circulating miRNAs was identified in UAE hypertensive subjects, regulating 21 pathways. Moreover, changes in the levels of 4 exosomes-miRNAs were validated in a confirmation cohort and found associated with albuminuria. In particular miR-26a, major regulator of TGF-β signaling, was found downregulated in both type of exosomes when compared with healthy controls and to hypertension normoalbuminurics (P<0.01). Similarly, decreased miR-26a levels were found in podocyte-derived exosomes after TGF-β stress. Our results revealed an exosomes miRNA signature associated to albuminuria in hypertension. In particular, exosomes miR-26a seemed to play a key role in the regulation of TGF-β, a relevant effector in podocyte damage. These findings support the use of exosomes miRNAs as biomarkers of cardiovascular risk progression and therapeutic tools in early kidney damage.

Chronic kidney disease as a cardiovascular risk factor

: Chronic kidney disease (CKD) is a public health threat with impact in cardiovascular risk. All forms of cardiovascular disease and mortality are more common in CKD. Treatment of cardiovascular risk factors, hypertension, dyslipidemia and diabetes is essential for cardiovascular and kidney protection. CKD is a marker of high or very high cardiovascular risk and its presence require early treatment and specific goals. Lifestyle is a pivotal factor, stopping smoking, reducing weight in the overweight or obese, starting regular physical exercise and healthy dietary pattern are recommended. Office BP should be lowered towards 130/80 mmHg or even lower if tolerated with sodium restriction and single pill combination, including angiotensin system blocker. Out-of-office BP monitoring, mainly 24-h assessment, is recommended. Diabetes requires treatment from the moment of diagnosis, but prediabetes benefits with lifestyle changes and metformin in patients stage 2 and 3a. iSGLT2 and GLP-1RA are initially recommended in T2D patients with high or very high cardiovascular risk. Concerning dyslipidemia, for patients in stage 4, LDL-C 55 mg/dl or less (1.4 mmol/l) and an LDL-C reduction of 50% or less from baseline is recommended. In stage 3, LDL-C goal is 70 mg/dl or less (1.8 mmol/l) and an LDL-C. reduction of at least 50% from baseline. Statins are the lipid-lowering therapy of choice with or without ezetimibe. Higher doses of statins are required as GFR declines. Available evidence suggests that combined PCSK9 inhibitors with maximally tolerated dose of statins may have an emerging role in treatment of dyslipidemia in CKD patients.

Urinary podocyte-associated molecules and albuminuria in hypertension

OBJECTIVE

Hypertension-induced podocyte damage and the relationship with UAE is analyzed in diabetic and nondiabetic participants.

PATIENTS AND METHODS

Sixty-four hypertensive patients, 30 diabetics, with glomerular filtration rate (eGFR) greater than 60 ml/min per 1.73 m were included. Urinary albumin excretion was measured in morning urine using a nephelometric immunoassay and expressed as albumin/creatinine ratio. Urinary pellets were obtained from fresh urine and mRNA was assessed by real-time quantitative PCR. Likewise, protein podocyte-specific molecules were measured by western blot using specific antibodies.

RESULTS

Fourteen nondiabetics and 20 diabetics had increased UAE greater than 30 mg/g. In individuals with increased EUA, the mRNA expression of nephrin and CD2AP was low in diabetics, whereas only nephrin mRNA in nondiabetics. No differences were observed in podocalyxin and aquaporin-1 mRNA levels. Concerning the protein values, in both nondiabetic and diabetic patients, nephrin, CD2AP and podocalyxin were increased in patients with increased UAE, with no differences in aquaporin-1. A significant positive relationship was observed between log UAE and nephrin protein values, and an inverse association observed with mRNA.

CONCLUSION

Hypertensive patients who had elevated UAE showed increased urinary excretion of podocyte-specific proteins coupled with a phenotype of decreased mRNA expression. The phenotype of podocyte-specific mRNA and the increment of nephrin can be used as a valuable marker of early glomerular injury.

Immune-unreactive urinary albumin as a predictor of cardiovascular events: the Hortega Study

BACKGROUND

We aimed to determine if immune-unreactive albumin excretion (IURAE) is associated with cardiovascular (CV) events in a representative sample of a general population from Spain.

METHODS

We included 1297 subjects (mean age ± standard error 48.0 ± 0.2 years, 48% females), who participated in the Hortega Follow-Up Study. The primary endpoint was incidence of fatal and non-fatal CV events. Urinary albumin excretion (UAE) was measured in spot voided urine, frozen at -80°C, by immunonephelometry [immune-reactive albumin excretion (IRAE)] and by high-performance liquid chromatography (HPLC) [total albumin excretion (AE)]. IURAE was calculated as the difference between HPLC measurements and IRAE. We estimated fully adjusted hazard ratios (HRs) of CV incidence by Cox regression for IRAE, IURAE and total AE.

RESULTS

After an average at-risk follow-up of 13 years, we observed 172 CV events. urinary albumin to creatinine ratio (UACR) of ≥30 mg/g assessed by IRAE, IURAE or total AE concentrations was observed in 74, 273 and 417 participants, respectively. Among discordant pairs, there were 49 events in those classified as micro- and macroalbuminuric by IURAE, but normoalbuminuric by IRAE. Only the IRAE was a significant independent factor for the incidence of CV events [HR (95% confidence interval) 1.15 (1.04-1.27)]. The association of UAE with CV events was mainly driven by heart failure (HF) [HR 1.33 (1.15-1.55) for IRAE; HR 1.38 (1.06-1.79) for IURAE; HR 1.62 (1.22-2.13) for total AE]. Those subjects who were micro- and macroalbuminuric by both IRAE and IURAE had a significant increase in risk for any CV event, and especially for HF.

CONCLUSIONS

IRAE, IURAE and AE were associated with an increased risk for CV events, but IRAE offered better prognostic assessment.

The endogenous cardiotonic steroid Marinobufagenin and decline in estimated glomerular filtration rate at follow-up in patients with arterial hypertension

BACKGROUND

Marinobufagenin (MBG) is an endogenous cardiotonic steroid (CTS) that inhibits the Na+/K+-ATPase. Human MBG is significantly increased in end-stage renal disease and immunization against MBG attenuates cardiovascular fibrosis in a rat model of uremic cardiomyopathy. Mineralocorticoid antagonists (MRA) block MBG binding sites and decrease proteinuria in chronic kidney disease (CKD) patients. We therefore aimed to investigate the association of MBG and albuminuria, as a marker of renal damage, as well as MBG and decline of glomerular filtration rate (GFR).

METHODS

The Graz endocrine causes of hypertension (GECOH) study is a single center study of adults routinely referred for screening of endocrine hypertension. Plasma MBG was measured by an enzyme-linked immunoassay, and in a post-hoc analysis, follow-up creatinine levels were obtained. Patients with proteinuria >3.5g/day at baseline were excluded from further evaluation.

RESULTS

We measured MBG concentrations in 40 hypertensive subjects and excluded one patient due to pre-existing proteinuria. Plasma MBG was significantly correlated with albuminuria (Spearman ρ = .357; p = .028) and proteinuria (ρ = .336; p = .039). In linear regression analysis, the association remained significant after adjustment for age, sex, and BMI (β = .306; p = .036), and for mean systolic blood pressure (β = .352; p = .034). In follow-up analyses (N = 30), MBG was significantly associated with decline in GFR after adjustment for time-to-follow-up (β = -.374; p = .042).

CONCLUSION

The findings suggest that MBG plasma concentrations were associated with albuminuria as well as decline in kidney function. Whether MBG predicts hard renal endpoints warrants further investigations.

Cross-sectional and longitudinal assessments of risk factors associated with hypertension and moderately increased albuminuria comorbidity in patients with type 2 diabetes: a 9-year open cohort study

BACKGROUND

Moderately increased albuminuria (MIA) is strongly associated with hypertension (HTN) in patients with type 2 diabetic mellitus (T2DM). However, the association between risk factors and coexisting HTN and MIA remains unassessed.

OBJECTIVES

This study aimed to determine both cross-sectional and longitudinal associations of risk factors with HTN and MIA comorbidity in patients with T2DM.

METHODS

A total of 1,600 patients with T2DM were examined at baseline and longitudinal data were obtained from 1,337 T2DM patients with at least 2 follow-up visits to assess the presence of HTN alone (yes/no), MIA alone (yes/no) and the coexistence of both (yes/no) in a 9-year open cohort study between 2004 and 2013. Bivariate mixed-effects logistic regression with a Bayesian approach was employed to evaluate associations of risk factors with HTN and MIA‎ comorbidity in the longitudinal assessment.

RESULTS

After adjustment for age and BMI, patients with uncontrolled plasma glucose, as a combined index of the glucose profile, were more likely to have HTN [odds ratio (OR): 1.73 with 95% Bayesian credible intervals (BCI) 1.29-2.20] and MIA [OR: 1.34 (‎95% BCI 1.13-1.62)]. The risks of having HTN and MIA were increased by a one-year raise in diabetes duration [with 0.89 (95% BCI 0.84-0.96) and 0.81 (95% BCI 0.73-0.92) ORs, respectively] and a one-unit increase in non-high-density lipoprotein-cholesterol (Non-HDL-C) [with 1.30 (95% BCI 1.23-1.34) and 1.24 (95% BCI 1.14-1.33) ORs, respectively].

CONCLUSIONS

T2DM patients with HTN,‎ MIA, and the coexistence of both had uncontrolled plasma glucose, significantly higher Non-HDL-C, and shorter diabetes duration than the other T2DM patients. Duration of diabetes and uncontrolled plasma glucose index showed the stronger effects on HTN and MIA comorbidity than on each condition separately.

Precision Healthcare of Type 2 Diabetic Patients Through Implementation of Haptoglobin Genotyping

It is well-recognized that there is a need for medicine to migrate to a platform of delivering preventative care based on an individual's genetic make-up. The US National Research Council, the National Institute of Health and the American Heart Association all support the concept of utilizing genomic information to enhance the clinical management of patients. It is believed this type of precision healthcare will revolutionize health management. This current attitude of some of the most respected institutes in healthcare sets the stage for the utilization of the haptoglobin (Hp) genotype to guide precision management in type 2 diabetics (DM). There are three main Hp genotypes: 1-1, 2-1, 2-2. The Hp genotype has been studied extensively in (DM) and from the accumulated data it is clear that Hp should be considered in all DM patients as an additional independent cardiovascular disease (CVD) risk factor. In DM patients Hp2-2 generates five times increased risk of CVD compared to Hp1-1 and three times increased risk compared to Hp2-1. Data has also shown that carrying the Hp2-2 gene in DM compared to carrying an Hp1-1 genotype can increase the risk the microvascular complications of nephropathy and retinopathy. In addition, the Hp2-2 gene enhances post percutaneous coronary intervention (PCI) complications such as, in stent restenosis and need for additional revascularization during the first-year post PCI. Studies have demonstrated significant mitigation of CVD risk in Hp2-2 DM patients with administration of vitamin E and maintaining tight glycemic control. CVD is the leading cause of death and disability in DM as well-representing a huge financial burden. As such, evaluating the Hp genotype in DM patients can enhance the predictability and management of CVD risk.

Finerenone Attenuates Endothelial Dysfunction and Albuminuria in a Chronic Kidney Disease Model by a Reduction in Oxidative Stress

Albuminuria is an early marker of renovascular damage associated to an increase in oxidative stress. The Munich Wistar Frömter (MWF) rat is a model of chronic kidney disease (CKD), which exhibits endothelial dysfunction associated to low nitric oxide availability. We hypothesize that the new highly selective, non-steroidal mineralocorticoid receptor (MR) antagonist, finerenone, reverses both endothelial dysfunction and microalbuminuria. Twelve-week-old MWF (MWF-C; MWF-FIN) and aged-matched normoalbuminuric Wistar (W-C; W-FIN) rats were treated with finerenone (FIN, 10 mg/kg/day p.o.) or vehicle (C) for 4-week. Systolic blood pressure (SBP) and albuminuria were determined the last day of treatment. Finerenone lowered albuminuria by >40% and significantly reduced SBP in MWF. Aortic rings of MWF-C showed higher contractions to either noradrenaline (NA) or angiotensin II (Ang II), and lower relaxation to acetylcholine (Ach) than W-C rings. These alterations were reversed by finerenone to W-C control levels due to an upregulation in phosphorylated Akt and eNOS, and an increase in NO availability. Apocynin and 3-amino-1,2,4-triazole significantly reduced contractions to NA or Ang II in MWF-C, but not in MWF-FIN rings. Accordingly, a significant increase of Mn-superoxide dismutase (SOD) and Cu/Zn-SOD protein levels were observed in rings of MWF-FIN, without differences in p22phox, p47phox or catalase levels. Total SOD activity was increased in kidneys from MWF-FIN rats. In conclusion, finerenone improves endothelial dysfunction through an enhancement in NO bioavailability and a decrease in superoxide anion levels due to an upregulation in SOD activity. This is associated with an increase in renal SOD activity and a reduction of albuminuria.

Urinary exosome miR-146a is a potential marker of albuminuria in essential hypertension

Background

There is increasing interest in using extracellular vesicle-derived microRNAs (miRNAs) as biomarkers in renal dysfunction and injury. Preliminary evidence indicates that miRNAs regulate the progression of glomerular disease. Indeed, exosomes from the renal system have provided novel evidence in the clinical setting of albuminuria. Thus, the aim of this study was to quantify the urinary miRNAs present in exosome and microvesicles (MVs), and to assess their association with the presence of increased urinary albumin excretion in essential hypertension.

Methods

Exosomes were collected from urine specimens from a cohort of hypertensive patients with (n = 24) or without albuminuria (n = 28), and from 20 healthy volunteers as a control group. Urinary exosomes were phenotyped by Western blot, tunable resistive pulse sensing, and electronic microscopy. Expression of miR-146a and miR-335* was analysed by qRT-PCR and any associations between albuminuria and exosomal miRNAs were analysed.

Results

Urinary miRNAs are highly enriched in exosome subpopulations compared to MVs, both in patients with or without increased albuminuria (p < 0.001), but not in the control group. High albuminuria was associated with 2.5-fold less miR-146a in exosomes (p = 0.017), whereas miR-146a levels in MV did not change. In addition, exosome miR-146a levels were inversely associated with albuminuria (r = 0.65, p < 0.0001), and discriminated the presence of urinary albumin excretion presence [area under the curve = 0.80, 95% confidence interval: 0.66–0.95; p = 0.0013].

Conclusions

Our results indicate that miRNAs were enriched in the urinary exosome subpopulation in hypertensive patients and that low miR-146a expression in exosomes was associated with the presence of albuminuria. Thus, urinary exosome miR-146a may be a potentially useful tool for studying early renal injury in hypertension.

Urinary exosomes reveal protein signatures in hypertensive patients with albuminuria

Albuminuria is an indicator of cardiovascular risk and renal damage in hypertensive individuals. Chronic renin-angiotensin system (RAS) suppression facilitates blood pressure control and prevents development of new-onset-albuminuria. A significant number of patients, however, develop albuminuria despite chronic RAS blockade, and the physiopathological mechanisms are underexplored. Urinary exosomes reflect pathological changes taking place in the kidney. The objective of this work was to examine exosomal protein alterations in hypertensive patients with albuminuria in the presence of chronic RAS suppression, to find novel clues underlying its development. Patients were followed-up for three years and were classified as: a) patients with persistent normoalbuminuria; b) patients developing de novo albuminuria; and c) patients with maintained albuminuria. Exosomal protein alterations between groups were identified by isobaric tag quantitation (iTRAQ). Confirmation was approached by target analysis (SRM). In total, 487 proteins were identified with high confidence. Specifically, 48 proteins showed an altered pattern in response to hypertension and/or albuminuria. Out of them, 21 proteins interact together in three main functional clusters: glycosaminoglycan degradation, coagulation and complement system, and oxidative stress. The identified proteins constitute potential targets for drug development and may help to define therapeutic strategies to evade albuminuria progression in hypertensive patients chronically treated.

Blood pressure targets in type 2 diabetes. Evidence against or in favour of an aggressive approach

When associated with high blood pressure, type 2 diabetes mellitus is characterised by a high risk of adverse cardiovascular (CV) and renal outcomes. However, both can be effectively reduced by antihypertensive treatment. Current guidelines on the treatment of hypertension emphasize the need to effectively treat high blood pressure in diabetic individuals, but their recommendations differ in terms of the optimal target blood pressure value to aim for in order to maximise CV and renal protection. In some guidelines the recommended target blood pressure values are <140/90 mmHg (systolic/diastolic), whereas in others, blood pressure values close or even less than 130/80 mmHg are recommended. This paper will discuss the evidence for and against a conservative or more aggressive blood pressure target for treated diabetic hypertensive individuals based on the evidence provided by randomised trials, trial meta-analyses and large observational studies. Based on the available evidence, it appears that blood pressure targets will probably have to be lower than <140/90 mmHg, and that values approaching 130/80 mmHg should be recommended. However, evidence in favour of even lower systolic values, i.e. <130 mmHg, is limited and is definitively against a reduction to <120 mmHg.

Immune system deregulation in hypertensive patients chronically RAS suppressed developing albuminuria

Albuminuria development in hypertensive patients is an indicator of higher cardiovascular (CV) risk and renal damage. Chronic renin-angiotensin system (RAS) suppression facilitates blood pressure control but it does not prevent from albuminuria development. We pursued the identification of protein indicators in urine behind albuminuria development in hypertensive patients under RAS suppression. Urine was collected from 100 patients classified in three groups according to albuminuria development: (a) patients with persistent normoalbuminuria; (b) patients developing de novo albuminuria; (c) patients with maintained albuminuria. Quantitative analysis was performed in a first discovery cohort by isobaric labeling methodology. Alterations of proteins of interest were confirmed by target mass spectrometry analysis in an independent cohort. A total of 2416 proteins and 1223 functional categories (coordinated protein responses) were identified. Immune response, adhesion of immune and blood cells, and phagocytosis were found significantly altered in patients with albuminuria compared to normoalbuminuric individuals. The complement system C3 increases, while Annexin A1, CD44, S100A8 and S100A9 proteins showed significant diminishment in their urinary levels when albuminuria is present. This study reveals specific links between immune response and controlled hypertension in patients who develop albuminuria, pointing to potential protein targets for novel and future therapeutic interventions.

[Relationship between blood pressure variability and combined cardiovascular events in 5-10 years in hypertensive patients]

OBJECTIVE

To explore the relationship between blood pressure variability (BPV) and combined cardiovascular events in 5-10 years in patients with hypertension.

METHODS

A total of 367 hypertensive patients treated in our hospital from January, 2000 to January, 2005 were analyzed, and their BPV was assessed in comparison with 145 normotensive individuals. The hypertensive patients were classified into high BPV group and low BPV group, and the general clinical data and biochemical profiles were compared. The relationship between BPV and combined cardiovascular events of the patients within 5-10 years were explored.

RESULTS

Compared with the normotensive individuals, the hypertensive patients showed significantly increased standard deviation and coefficient of variation of 24-h systolic blood pressure (SBP), 24-h diastolic blood pressrue (DBP), daytime SBP, daytime DBP, night-time SBP and night-time DBP (P<0.01). The percentages of drinking, smoking, diabetes and coronary heart disease were significantly higher in patients with high BPV than those with lower BPV (P<0.01 or 0.05); uric acid, homocysteine, urinary protein/creatinine ratio and urinary microalbumin increased more significantly in patients with high BPV (P<0.01 or 0.05). In addition, the combined cardiovascular events in 5-10 years were significantly higher in the patients with higher BPV than those with lower BPV (P<0.01 or 0.05). Logistic multivariate logistic regression analysis showed that alcohol, diabetes, coronary heart disease, uric acid and homocysteine were independent risk factors for cardiovascular events in hypertensive patients (P<0.01 or 0.05).

CONCLUSION

In hypertensive patients, BPV is closely correlated with the long-term combined cardiovascular events, and a high BPV is associated with a greater likeliness of combined cardiovascular events.

Comparison between the effects of hydrochlorothiazide and indapamide on the kidney in hypertensive patients inadequately controlled with losartan

The aim of the study is to compare the effects of hydrochlorothiazide and indapamide on the kidney in patients with hypertension inadequately controlled with losartan. A total of 140 patients who met the criteria and inadequately controlled with losartan 50 mg per day for 2 weeks were randomized in two groups and administered either hydrochlorothiazide 12.5 mg per day (n=70) or indapamide (sustained release) 1.5 mg per day (n=70) in combination with losartan 50 mg per day. Office blood pressure (BP) were collected at baseline and upon each follow-up visit. Creatinine, urine albumin-creatinine ratio (ACR), urine neutrophil gelatinase-associated lipocalin (NGAL) and renal resistive index (RRI) were also collected at baseline and at the 24-week follow-up. None of the baseline characteristics was statistically significantly different between the two groups. After excluding those patients with office BP uncontrolled, 46 patients in the hydrochlorothiazide group (45.7% males, 58.8±10.8 years) and 44 patients in the indapamide group (38.4% males, 61.5±10.9 years) were analysed. There were insignificant changes in creatinine and significant decreases in ACR, NGAL and RRI compared to baseline levels in the two groups. The decrease in ACR (3.8 (0, 28.7) vs 4.2 (0.4, 64.8) mg g^-1, P=0.485) was not significantly different between the two groups, while the decrease in NGAL (16.07±7.07 vs 28.77±7.64 ng ml^-1, P<0.001) and RRI (0.04±0.02 vs 0.07±0.04, P<0.001) was more significant in the indapamide group than in the hydrochlorothiazide group. In conclusion, indapamide is superior to hydrochlorothiazide to improve renal tubular injury and renal haemodynamics in combination with losartan in hypertensive patients with controlled BP.

Arterial Destiffening in Previously Untreated Mild Hypertensives After 1 Year of Routine Clinical Management

BACKGROUND

Arterial stiffness, measured with pulse wave velocity (PWV), is now classified as a marker of target organ damage (TOD) alongside left ventricular hypertrophy and moderately increased albuminuria. Interventional studies on treated hypertensive patients have shown that PWV could be improved. Our aim was to assess changes in arterial stiffness after 1 year of routine clinical practice in never-treated hypertensive patients.

PATIENTS AND METHODS

We studied 356 never-treated patients with suspected hypertension. After standard clinical assessment during which presence of TOD was evaluated, hypertension diagnosis was confirmed in 231 subjects who subsequently received standard routine care. Both hypertensive and the 125 controls came back for a follow-up visit after 1 year.

RESULTS

Hypertensive patients were slightly older (46 ± 12 vs. 50 ± 12 years, P < 0.001), with higher mean arterial pressure (MAP)-adjusted PWV compared to controls (8.6 ± 2.0 vs. 8.0 ± 1.7 m/s, P < 0.001) and 47% of them presented 1 or more TOD. After 1 year of treatment, MAP was similar in both groups (94.9 vs. 96.2 mm Hg; P = ns), but adjusted PWV remained significantly higher in the hypertensive patients (7.8 ± 1.4 vs. 8.3 ± 1.7 m/s, P = 0.004). The prevalence of elevated PWV was reduced from 20% to 12%. All antihypertensive drugs achieved the same blood pressure (BP) and PWV reduction with the exception of vasodilating beta-blockers which gave slightly better results probably due to heart rate reduction.

CONCLUSION

BP reduction in newly diagnosed hypertensive patients improves arterial stiffness within a year of real-life clinical practice. Patients with the highest PWV and the largest reduction of BP "destiffened" the most whatever antihypertensive class was used.

Microalbuminuria predicts the recurrence of cardiovascular events in patients with essential hypertension

OBJECTIVES

Microalbuminuria (MAU) is associated with an enhanced risk of cardiovascular events. The prevalence of MAU and its prognostic impact has an important role in the stratification of cardiovascular risk in patients with essential hypertension. This is an observational, prospective study performed by 13 general practitioners aiming at assessing the prevalence and prognostic relevance of MAU in essential hypertension.

METHODS

Patients with essential hypertension and with recent determination of MAU were enrolled into the study by general practitioners, and were followed up for 3 years. Primary end point was the occurrence of major cardiovascular events during the follow-up.

RESULTS

Out of 1024 unselected patients, consecutively enrolled from January 2009 to March 2010, 804 completed the 3-year follow-up. Patients were categorized into two groups according to the absence (n = 523, 65%) or presence (n = 281, 35%) of MAU. During the follow-up, 41 cardiovascular events (1.69 events/100 patient-years) were reported. The presence of MAU was not associated with increased risk of cardiovascular events (adjusted hazard ratio = 1.32; 95% confidence interval 0.290-4.340, P = 0.097). When the analysis was restricted to the patients with previous cardiovascular event, MAU (adjusted hazard ratio = 2.18; 95% confidence interval 0.42-2.43, P = 0.031), together with age, metabolic syndrome, diabetes, and smoking, independently predicted the occurrence of cardiovascular events.

CONCLUSION

Presence of MAU in patients with essential hypertension is not associated with increased risks of cardiovascular events. At the variance, in patients with previous cardiovascular events, MAU was found to predict recurrent events. Thus, the assessment of MAU could be considered a useful tool in secondary prevention.

Lercanidipine valuable effect on urine protein losses: the RED LEVEL study

OBJECTIVE

The RED LEVEL study (REnal Disease: LErcanidipine Valuable Effect on urine protein Losses) directly compares, in an explorative fashion, the effects of lercanidipine + enalapril and amlodipine + enalapril combinations on renal parameters in hypertensive subjects.

RESEARCH DESIGN AND METHODS

This was a 1 year, prospective, multi-center, randomized, open-label, blinded-endpoint (PROBE) study in hypertensive patients with albuminuria.

MAIN OUTCOME MEASURES

Renal function (albuminuria, serum creatinine, creatinine clearance, estimated glomerular filtration rate and proteinuria); blood pressure.

RESULTS

Albuminuria was significantly reduced, compared with baseline values, with the lercanidipine + enalapril combination over the entire study period; at month 3, month 6 and month 12, changes from baseline were: -162.5 (p-value = 0.0439), -425.8 (p-value = 0.0010), -329.0 (p-value = 0.0011) mg/24 h), respectively. On the other hand, this improvement was not observed with enalapril + amlodipine. Other parameters of renal function such as serum creatinine, creatinine clearance, estimated glomerular filtration rate and proteinuria did not change over the study. Both lercanidipine + enalapril and amlodipine + enalapril significantly reduced systolic and diastolic blood pressure values from baseline all over the study period with no significant differences between groups. Safety outcomes were comparable between the two groups.

CONCLUSIONS

Overall, the results of this explorative study lend support to the anti-albuminuric effect of the lercanidipine + enalapril combination and to the long term renal-protective effects of this combination in patients with hypertension.

Microalbuminuria could improve risk stratification in patients with TIA and minor stroke

Objective

Transient ischemic attacks (TIA) and minor strokes are important risk factors for recurrent strokes. Current stroke risk prediction scores such as ABCD2, although widely used, lack optimal sensitivity and specificity. Elevated urinary albumin excretion predicts cardiovascular disease, stroke, and mortality. We explored the role of microalbuminuria (using albumin creatinine ratio (ACR)) in predicting recurrence risk in patients with TIA and minor stroke.

Methods

Urinary ACR was measured on a spot sample in 150 patients attending a daily stroke clinic with TIA or minor stroke. Patients were followed up at day 7, 30, and 90 to determine recurrent stroke, cardiovascular events, or death. Eligible patients had a carotid ultrasound Doppler investigation. High‐risk patients were defined as those who had an event within 90 days or had >50% internal carotid artery (ICA) stenosis.

Results

Fourteen (9.8%) recurrent events were reported by day 90 including two deaths. Fifteen patients had severe ICA stenosis. In total, 26 patients were identified as high risk. These patients had a higher frequency of previous stroke or hypercholesterolemia compared to low‐risk patients (P = 0.04). ACR was higher in high‐risk patients (3.4 [95% CI 2.2–5.2] vs. 1.7 [1.5–2.1] mg/mmol, P = 0.004), independent of age, sex, blood pressure, diabetes, and previous stroke. An ACR greater than 1.5 mg/mmol predicted high‐risk patients (Cox proportional hazard ratio 3.5 (95% CI 1.3–9.5, P = 0.01).

Interpretation

After TIA or minor stroke, a higher ACR predicted recurrent events and significant ICA stenosis. Incorporation of urinary ACR from a spot sample in the acute setting could improve risk stratification in patients with TIA and minor stroke.

The kidney in obesity

Body mass index has been found to be the second most important contributor to relative risk for developing end state renal disease (ESRD), after proteinuria. The impact of obesity on the kidney includes a wide spectrum, from characteristic pathologic lesions to increment in urinary albumin excretion (UAE) and proteinuria/or decrease in glomerular filtration rate (GFR). The cause of renal disease associated to obesity is not well understood, but two relevant elements emerge. The first is the presence of obesity-related glomerulopathy, and the second is the fat deposit in the kidney with impact on renal haemodynamics and intrarenal regulation. The mechanisms linking obesity and renal damage are complex and include haemodynamic changes, inflammation, oxidative stress, apoptosis, and finally renal scarring. The protection of kidney damage needs to combine weight reduction with the proper control of the cardiometabolic risk factors associated, hypertension, metabolic syndrome, diabetes and dyslipidaemia. The search for specific treatments merits future research.

Fetal Endothelial Remodeling in Late-Onset Gestational Hypertension

BACKGROUND

Recent studies reveal that offspring of pregnancies complicated by hypertensive disorders may have an increased cardiovascular risk. Genetic and nongenetic factors seem to play an important role in premature arterial disease. Endothelium may be significant for long-term remodeling of the arterial wall. The aim of the study was to assess fetal endothelial and renal function in late-onset gestational hypertension.

MATERIALS AND METHODS

This was a case-controlled study. Singleton pregnancies affected by late-onset gestational hypertension (after 34 weeks' gestation) and controls were included. Ultrasound examinations (fetal biometry, fetal Doppler, fetal aorta intima media thickness (aIMT), fetal kidney volumes, maternal Doppler, presence of uterine arteries protodiastolic notching from anomaly scan) and clinical data were collected. A sample of amniotic fluid was taken at delivery.

RESULTS

Fifty patients with late-onset hypertension and 50 controls were included. At growth scan (weeks 29-32) we found in the study group significantly higher fetal aIMT, umbilical artery pulsatility index (PI), fetal aorta PI, and mean uterine arteries PI with persistent bilateral notch. In the case group microalbuminuria levels were significantly higher than controls (1.32±0.11 vs. 1.10±0.13g/l, P < 0.0001), and there was a negative correlation between renal fetal volume at growth scan and amniotic microalbuminuria (r: -0.95, 95% C -0.97 to -0.90, P < 0.0001).

CONCLUSIONS

Gestational hypertension should be considered as one of the adverse early risk factors that might predispose to impaired fetal cardiovascular development during intrauterine life; therefore, this study provides further evidence to better understand the origins of cardiovascular diseases.

Urinary alpha-1 antitrypsin and CD59 glycoprotein predict albuminuria development in hypertensive patients under chronic renin-angiotensin system suppression

BACKGROUND

Hypertension is a multi-factorial disease of increasing prevalence and a major risk factor for cardiovascular mortality even in the presence of adequate treatment. Progression of cardiovascular disease (CVD) occurs frequently during chronic renin-angiotensin-system (RAS) suppression, and albuminuria is a marker of CV risk. High prevalence of albuminuria in treated hypertensive patients has been demonstrated, but there are no available markers able to predict evolution. The aim of this study was the identification of novel indicators of albuminuria progression measurable in urine of diabetic and non-diabetic patients.

METHODS

1143 hypertensive patients under chronic treatment were followed for a minimum period of 3 years. Among them, 105 diabetic and non-diabetic patients were selected and classified in three groups according to albuminuria development during follow-up: (a) patients with persistent normoalbuminuria; (b) patients developing de novo albuminuria; (c) patients with maintained albuminuria. Differential urine analysis was performed by 2D gel electrophoresis (2D-DIGE) and further confirmed by liquid chromatography-mass spectrometry. Non-parametric statistical tests were applied.

RESULTS

CD59 glycoprotein and alpha-1 antitrypsin (AAT) resulted already altered in patients developing albuminuria de novo, with a similar response in those with maintained albuminuria. A prospective study in a sub-group of normoalbuminuric patients who were clinically followed up for at least 1 year from urine sampling, revealed CD59 and AAT proteins significantly varied in the urine collected from normoalbuminurics who will negatively progress, serving as predictors of future albuminuria development.

CONCLUSIONS

CD59 and AAT proteins are significantly altered in hypertensive patients developing albuminuria. Interestingly, CD59 and AAT are able to predict, in normoalbuminuric individuals, who will develop albuminuria in the future, being potential predictors of vascular damage and CV risk. These findings contribute to early identify patients at risk of developing albuminuria even when this classical predictor is still in the normal range, constituting a novel strategy towards a prompt and more efficient therapeutic intervention with better outcome.

Subclinical Kidney Damage in Hypertensive Patients: A Renal Window Opened on the Cardiovascular System. Focus on Microalbuminuria

The kidney is one of the major target organs of hypertension.Kidney damage represents a frequent event in the course of hypertension and arterial hypertension is one of the leading causes of end-stage renal disease (ESRD).ESRD has long been recognized as a strong predictor of cardiovascular (CV) morbidity and mortality. However, over the past 20 years a large and consistent body of evidence has been produced suggesting that CV risk progressively increases as the estimated glomerular filtration rate (eGFR) declines and is already significantly elevated even in the earliest stages of renal damage. Data was supported by the very large collaborative meta-analysis of the Chronic Kidney Disease Prognosis Consortium, which provided undisputable evidence that there is an inverse association between eGFR and CV risk. It is important to remember that in evaluating CV disease using renal parameters, GFR should be assessed simultaneously with albuminuria.Indeed, data from the same meta-analysis indicate that also increased urinary albumin levels or proteinuria carry an increased risk of all-cause and CV mortality. Thus, lower eGFR and higher urinary albumin values are not only predictors of progressive kidney failure, but also of all-cause and CV mortality, independent of each other and of traditional CV risk factors.Although subjects with ESRD are at the highest risk of CV diseases, there will likely be more events in subjects with mil-to-moderate renal dysfunction, because of its much higher prevalence.These findings are even more noteworthy when one considers that a mild reduction in renal function is very common in hypertensive patients.The current European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines for the management of arterial hypertension recommend to sought in every patient signs of subclinical (or asymptomatic) renal damage. This was defined by the detection of eGFR between 30 mL/min/1.73 m² and 60 mL/min/1.73 m² or the presence of microalbuminuria (MAU), that is an amount of albumin in the urine of 30-300 mg/day or an albumin/creatinine ratio, preferentially on morning spot urine, of 30-300 mg/g.There is clear evidence that urinary albumin excretion levels, even below the cut-off values used to define MAU, are associated with an increased risk of CV events. The relationships of MAU with a variety of risk factors, such as blood pressure, diabetes and metabolic syndrome and with several indices of subclinical organ damage, may contribute, at least in part, to explain the enhanced CV risk conferred by MAU. Nonetheless, several studies showed that the association between MAU and CV disease remains when all these risk factors are taken into account in multivariate analyses. Therefore, the exact pathophysiological mechanisms explaining the association between MAU and CV risk remain to be elucidated. The simple search for MAU and in general of subclinical renal involvement in hypertensive patients may enable the clinician to better assess absolute CV risk, and its identification may induce physicians to encourage patients to make healthy lifestyle changes and perhaps would prompt to more aggressive modification of standard CV risk factors.

Microalbuminuria in subjects with hypertension attending specialist blood pressure clinics

Albuminuria is associated with increased risk of cardiovascular disease and target organ damage in patients with diabetes mellitus. In nondiabetic hypertensive patients, the threshold at which microalbuminuria (MAU) increases risk is unclear and there is evidence that cardiovascular risk may be increased in individuals with MAU levels lower than the usual recommended screening thresholds. We compared two definitions of MAU (on the basis of three early morning urine samples) in a cohort of hypertensive patients attending two specialist clinics in Scotland: conventional (MAU(C)) albumin-to-creatinine ratio (ACR) >2.5-25 mg mmol(-1) in males or >3.5-25 mg mmol(-1) in females; and low-grade (MAU(L)) ACR 1.2-2.5 in males or 1.7-3.5 mg mmol(-1) in females. Of the 1059 subjects screened, 786 (74%) were nondiabetic, with estimated glomerular filtration rate ⩾30 ml min(-1) per 1.73 m(2) and without gross proteinuria (low-risk subset). The average age was 58±15 years, body mass index 30±6 kg m(-2) and 46% were males. The prevalence of MAU(C) was 11% and 9.5% in the overall and low-risk subset, respectively, whereas MAU(L) prevalence was 11.1% and 10% respectively. The prevalence of cardiovascular disease was higher (24%) with albuminuria (both MAU(C) and MAU(L)) compared with 14% among those without albuminuria. The use of MAU(L) doubled the number of hypertensive subjects with increased cardiovascular risk who can be targeted for more rigorous risk reduction strategies. Consideration should be given to reducing the current threshold for MAU.