Levels of NT-proBNP, markers of low-grade inflammation, and endothelial dysfunction during spironolactone treatment in patients with diabetic kidney disease

Minireview: Understanding and targeting inflammatory, hemodynamic and injury markers for cardiorenal protection in type 1 diabetes

The coexistence of cardiovascular disease (CVD) and diabetic kidney disease (DKD) is common in people with type 1 diabetes (T1D) and is strongly associated with an increased risk of morbidity and mortality. Hence, it is imperative to explore robust tools that can accurately reflect the development and progression of cardiorenal complications. Several cardiovascular and kidney biomarkers have been identified to detect at-risk individuals with T1D. The primary aim of this review is to highlight biomarkers of injury, inflammation, or renal hemodynamic changes that may influence T1D susceptibility to CVD and DKD. We will also examine the impact of approved pharmacotherapies for type 2 diabetes, including renin-angiotensin-aldosterone system (RAAS) inhibitors, sodium-glucose cotransporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RAs) on candidate biomarkers for cardiorenal complications in people with T1D and discuss how these changes may potentially mediate kidney and cardiovascular protection. Identifying predictive and prognostic biomarkers for DKD and CVD may highlight potential drug targets to attenuate cardiorenal disease progression, implement novel risk stratification measures in clinical trials, and improve the assessment, diagnosis, and treatment of at-risk individuals with T1D.

Renoprotective Effects of Mineralocorticoid Receptor Antagonists Against Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a growing epidemic worldwide and a leading cause of end-stage kidney disease. Mineralocorticoid receptor (MR) blockade using Finerenone is a recently approved therapeutic approach to slow down the progression of DKD in patients with type 2 diabetes in addition to other therapies such as angiotensin-II converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), sodium-glucose co-transporter 2 (SGLT2) inhibitors, and glucagon-like peptide 1 (GLP-1) analogs. This review elaborates on the pathophysiologic pathways activated by aldosterone (the human mineralocorticoid) in DKD, the pharmacology of three different generations of mineralocorticoid receptor antagonists (MRAs), specifically, spironolactone, eplerenone, and finerenone, and the mechanisms by which these MRAs elicit their protective effects on the kidney under diabetic settings.

Immunomodulatory Potential of Diuretics

In this review, diuretics and their immunomodulatory functions are described. The effects on the immune response of this group of drugs are reported in patients suffering from hypertension and under experimental conditions involving animal models and cell line studies. The pathogenesis of hypertension is strongly connected to chronic inflammation. The vast majority of diuretics modulate the immune response, changing it in favor of the anti-inflammatory response, but depending on the drug, these effects may differ. This topic is significantly important in medical practice regarding the treatment of patients who have coexisting diseases with chronic inflammatory pathogenesis, including hypertension or chronic heart failure. In patients with metabolic syndrome, allergies, or autoimmune disorders, the anti-inflammatory effect is favorable, because of the overstimulation of their immune system. Otherwise, in the geriatric population, it is important to find the proper anti- and pro-inflammatory balance to avoid an enhancement of immune response suppression, which can result in reducing the risk of serious infections that can occur due to the age-diminished function of the immune system. This article is intended to facilitate the selection of an antihypertensive drug that depends on the patient's immune situation.

Mineralocorticoid Receptor Antagonists in Diabetic Kidney Disease

Diabetes mellitus is a global health issue and main cause of chronic kidney disease. Both diseases are also linked through high cardiovascular morbidity and mortality. Diabetic kidney disease (DKD) is present in up to 40% of diabetic patients; therefore, prevention and treatment of DKD are of utmost importance. Much research has been dedicated to the optimization of DKD treatment. In the last few years, mineralocorticoid receptor antagonists (MRA) have experienced a renaissance in this field with the development of non-steroidal MRA. Steroidal MRA have known cardiorenal benefits, but their use is limited by side effects, especially hyperkalemia. Non-steroidal MRA still block the damaging effects of mineralocorticoid receptor overactivation (extracellular fluid volume expansion, inflammation, fibrosis), but with fewer side effects (hormonal, hyperkalemia) than steroidal MRA. This review article summarizes the current knowledge and newer research conducted on MRA in DKD.

The Ascent of Mineralocorticoid Receptor Antagonists in Diabetic Nephropathy

Diabetic nephropathy is defined as a decline in the renal function and an increase in the amount of albuminuria (>300 mg/day). The interruption of the renin-angiotensin-aldosterone system (RAAS) by well-established therapies such as angiotensin-converting enzyme inhibitor, angiotensin receptor blockers, calcium channel blockers or diuretics has been beneficial in reducing the progression of renal diseases; however, there is an increase in the levels of aldosterone due to the aldosterone escape phenomenon. Newer and novel approaches to counteract this aldosterone breakthrough while accentuating the anti-hypertensive and anti-proteinuric effects of these agents would be ideal and mineralocorticoid receptor antagonists fit in this slot perfectly. This review attempted to evaluate the safety and efficacy of and mineralocorticoid receptor antagonists for diabetic nephropathy. Presently mineralocorticoid receptor antagonists such as spironolactone, eplerenone and finerenone are being investigated as both monotherapies and as additional therapies. Clinical studies have shown that these drugs have been effective in the reduction of blood pressure, urinary-albumin-excretion and estimated glomerular filtration rate. The commonly observed adverse effects are hyperkalemia, gynaecomastia and vaginal bleeding, that are bothersome with spironolactone seems to be avoidable if these patients are switched to non-steroidal and mineralocorticoid receptor antagonists such as finerenone and eplerenone. Most of the studies have only evaluated the short-term effects of mineralocorticoid receptor antagonists on diabetic nephropathy. Hard outcomes such as cardiovascular events, creatinine doubling, progression to end-stage renal disease, mortality and the need for temporary or permanent dialysis need to be studied with these molecules.

Efficacy and safety of mineralocorticoid receptor antagonists with ACEI/ARB treatment for diabetic nephropathy: A meta-analysis

BACKGROUND

To explore the efficacy and safety of adding mineralocorticoid receptor antagonists (MRAs) to the treatment in diabetic nephropathy (DN) with ACEI/ARB.

METHODS

We systematically searched the PubMed, Embase and Cochrane Library databases for randomised controlled trials up to November 1st 2018 that evaluated the effects of MRAs with ACEI/ARB treatment.

RESULTS

The combination treatment of MRAs and ACEI/ARB further reduced urinary protein/albumin excretion compared with ACEI/ARB monotherapy (mean difference [MD], -44.17 [95% CIs, -61.73 to -26.61], P < .00001). Although no statistically significant changes in glomerular filtration rate were observed, the combination group significantly increased serum/plasma creatinine (MD, 7.40 [95% CIs, 4.69-10.11], P < .00001). Subgroup analysis based on generations of MRAs suggested a lower relative risk of hyperkalaemia with finerenone (relative risk, 2.22 [95% CIs, 0.13-38.13], P = .58) than eplerenone (relative risk, 2.81 [95% CIs, 1.03-7.69], P = .04) or spironolactone (relative risk, 4.58 [95% CIs, 2.60-8.08], P < .00001).

CONCLUSION

MRAs can significantly reduce proteinuria and increase blood creatinine in DN patients under blockade of the renin-angiotensin system. The combination treatment of finerenone and ACEI/ARB runs a lower risk of hyperkalaemia than eplerenone or spironolactone.

Effect of spironolactone for 1 yr on endothelial function and vascular inflammation biomarkers in renal transplant recipients

Kidney transplantation is associated with increased cardiovascular risk. Endothelial dysfunction and vascular inflammation contribute to negative outcome. In experimental models, mineralocorticoid receptor antagonists improved endothelial function and reduced inflammation. The present study tested the hypothesis that the mineralocorticoid receptor antagonist spironolactone improves endothelial function and reduces vascular inflammation in renal transplant patients. Eighty prevalent renal transplant patients from an ongoing, double-blind randomized placebo-controlled trial were included. Paired plasma samples before and after 1 yr of treatment (n = 39 in the spironolactone-treated group and 41 in the placebo-treated group) were used to determine markers of endothelial dysfunction (nitrite, nitrate, cGMP, arginine, citrulline, ornithine, asymmetric dimethylarginine, symmetric dimethylarginine, N^G-monomethyl-l-arginine, von Willebrand factor, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor 1 antigen) and markers of inflammation (intercellular adhesion molecule, vascular adhesion molecule, high-sensitivity C-reactive protein, and serum amyloid protein A). The median time since the transplantation was 4.6 (0.12-22.3) yr in the spironolactone-treated group and 2.1 (0.17-13.9) yr in the placebo-treated group (P > 0.05). Spironolactone increased plasma aldosterone (P < 0.001) and K⁺ (P < 0.001). Blood pressure did not change significantly. No significant differences were detected between groups in any of the measured markers of endothelial dysfunction or inflammation except in the subgroup analysis of patients with diabetes, where spironolactone decreased nitrite compared with placebo. In this study, mineralocorticoid receptor antagonism did not improve biomarkers of endothelial dysfunction or vascular inflammation in prevalent renal transplant patients. Further studies are needed to evaluate the potential beneficial effect of early or late mineralocorticoid receptor antagonism on vascular outcomes in renal transplant patients.

Mineralocorticoid Antagonism and Vascular Function in Early Autosomal Dominant Polycystic Kidney Disease: A Randomized Controlled Trial

RATIONALE & OBJECTIVE

Vascular dysfunction, characterized by impaired vascular endothelial function and increased large-elastic artery stiffness, is evident early in autosomal dominant polycystic kidney disease (ADPKD) and is an important predictor of cardiovascular events and mortality. Aldosterone excess has been implicated in the development of endothelial dysfunction and arterial stiffness, in part by causing increased oxidative stress and inflammation. We hypothesized that aldosterone antagonism would reduce vascular dysfunction in patients with early-stage ADPKD.

STUDY DESIGN

Prospective, randomized, controlled, double-blind, clinical trial.

SETTING & PARTICIPANTS

61 adults aged 20 to 55 years with ADPKD, estimated glomerular filtration rate ≥ 60mL/min/1.73m², and receiving a renin-angiotensin-aldosterone system inhibitor.

INTERVENTION

Spironolactone (maximum dose, 50mg/d) or placebo for 24 weeks.

OUTCOMES

Change in brachial artery flow-mediated dilation (FMD_BA) was the primary end point and change in carotid-femoral pulse-wave velocity (CFPWV) was the secondary end point.

RESULTS

60 participants completed the trial. Participants had a mean age of 34±10 (SD) years, 54% were women, and 84% were non-Hispanic white. Spironolactone did not change FMD_BA (8.0% ± 5.5% and 7.8% ± 4.3% at baseline and 24 weeks, respectively, vs corresponding values in the placebo group of 8.4% ± 6.2% and 8.0% ± 4.6%; P=0.9for comparison of change between groups) or CFPWV (640±127 and 603±101cm/s at baseline and 24 weeks, respectively, vs corresponding values in the placebo group of 659±138 and 658±131cm/s; P=0.1). Brachial systolic blood pressure was reduced with spironolactone (median change, -6 [IQR, -15, 1] vs -2 [IQR, -7, 10] mm Hg in the placebo group; P=0.04). Spironolactone did not change the majority of circulating and/or endothelial cell markers of oxidative stress/inflammation and did not change vascular oxidative stress.

LIMITATIONS

Low level of baseline vascular dysfunction; lack of aldosterone measurements.

CONCLUSIONS

24 weeks of aldosterone antagonism reduced systolic blood pressure without changing vascular function in patients with early-stage ADPKD.

FUNDING

NIDDK, NIH National Center for Advancing Translational Sciences, and the Zell Family Foundation.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCT01853553.

The Promise of Systems Biology for Diabetic Kidney Disease

Diabetic kidney disease (DKD) has a complex and prolonged pathogenesis involving many cell types in the kidney as well as extrarenal factors. It is clinically silent for many years after the onset of diabetes and usually progresses over decades. Given this complexity, a comprehensive and unbiased molecular approach is best suited to help identify the most critical mechanisms responsible for progression of DKD and those most suited for targeted intervention. Systems biological investigations provide such an approach since they examine the entire network of molecular changes that occur in a disease process in a comprehensive way instead of focusing on a single abnormal molecule or pathway. Systems biological studies can also start with analysis of the disease in humans, not in animal or cell culture models that often poorly reproduce the changes in human DKD. Indeed, in the last decade, systems biological approaches have led to the identification of critical molecular abnormalities in DKD and have directly led to development of new biomarkers and potential treatments for DKD.

Beneficial Effects of Pentoxifylline Plus Losartan Dual Therapy in Type 2 Diabetes with Nephropathy

BACKGROUND

This study was designed to comparatively assess the effects of add-on pentoxifylline to losartan versus increasing the dose of losartan on serum N-terminal pro-brain natriuretic peptide (NT-proBNP), serum highly sensitive C-reactive protein (hsCRP) and the urinary albumin excretion (UAE) rate in patients with type 2 diabetes and nephropathy.

METHODS

In an open-label, single-center, parallel-group, randomized clinical trial (NCT03006952), 30 patients received b.i.d. dose of pentoxifylline 400mg plus daily dose of losartan 50mg (pentoxifylline arm) and 29 patients received b.i.d. dose of losartan 50mg (losartan arm) during a 12-week follow-up period.

RESULTS

Serum NT-proBNP, serum hsCRP and UAE levels all significantly decreased from baseline in both trial arms. The pentoxifylline and losartan trial arms were equally effective in reducing serum NT-proBNP levels during the course of trial (multivariable adjusted model P value = 0.864, effect size = 0.2%). There was a greater decrease in UAE and serum hsCRP levels in the pentoxifylline arm (P = 0.034, effect size = 7.8%; P = 0.009, effect size = 11.7%, respectively). Conversely, patients in the losartan arm achieved better systolic and diastolic blood pressure control (P < 0.001, effect size = 25.4%; P = 0.010, effect size = 11.3%, respectively).

CONCLUSIONS

Circulating NT-proBNP levels equally and significantly reduced from baseline in the pentoxifylline and losartan treatment arms, in parallel with comparatively superior decreases of UAE and serum hsCRP in the pentoxifylline arm, and larger decreases of systolic and diastolic blood pressures in the losartan arm.

Effects of mineralocorticoid receptor antagonists on the progression of diabetic nephropathy

Aims/Introduction

We aimed to evaluate the potential benefits and adverse effects of adding a mineralocorticoid receptor antagonist (MRA) to angiotensin‐converting enzyme inhibitors (ACEI) and/or angiotensin receptor blockers (ARB), as standard treatment in patients with diabetic nephropathy.

Materials and Methods

We scanned the Embase, PubMed and Cochrane Central Register of Controlled Trials databases for human clinical trials published in English until June 2016, evaluating renal outcomes in patients with diabetic nephropathy.

Results

A total of 18 randomized controlled trials involving 1,786 patients were included. Compared with ACEI/ARB alone, co‐administration of MRA and ACEI/ARB significantly reduced urinary albumin excretion and the urinary albumin–creatinine ratio (mean difference −69.38, 95% confidence intervals −103.53 to −35.22, P < 0.0001; mean difference −215.74, 95% confidence intervals −409.22 to −22.26, P = 0.03, respectively). A decrease of blood pressure was also found in the co‐administration of MRA and ACEI/ARB groups. However, we did not observe any improvement in the glomerular filtration rate. There was a significant increase in the risk of hyperkalemia on the addition of MRA to ACEI/ARB treatment (relative risk 3.74, 95% confidence intervals 2.30–6.09, P < 0.00001).

Conclusions

These findings suggest that co‐administration of MRA and ACEI/ARB has beneficial effects on renal outcomes with increasing the incidence of hyperkalemia.

Role of the Renin-Angiotensin-Aldosterone System beyond Blood Pressure Regulation: Molecular and Cellular Mechanisms Involved in End-Organ Damage during Arterial Hypertension

Arterial hypertension is a common condition worldwide and an important predictor of several complicated diseases. Arterial hypertension can be triggered by many factors, including physiological, genetic, and lifestyle causes. Specifically, molecules of the renin-angiotensin-aldosterone system not only play important roles in the control of blood pressure, but they are also associated with the genesis of arterial hypertension, thus constituting a need for pharmacological interventions. Chronic high pressure generates mechanical damage along the vascular system, heart, and kidneys, which are the principal organs affected in this condition. In addition to mechanical stress, hypertension-induced oxidative stress, chronic inflammation, and the activation of reparative mechanisms lead to end-organ damage, mainly due to fibrosis. Clinical trials have demonstrated that renin-angiotensin-aldosterone system intervention in hypertensive patients lowers morbidity/mortality and inflammatory marker levels as compared to placebo patients, evidencing that this system controls more than blood pressure. This review emphasizes the detrimental effects that a renin-angiotensin-aldosterone system (RAAS) imbalance has on health considerations above and beyond high blood pressure, such as fibrotic end-organ damage.

Prognostic clinical and molecular biomarkers of renal disease in type 2 diabetes

Diabetic kidney disease occurs in ∼ 25-40% of patients with type 2 diabetes. Given the high risk of progressive renal function loss and end-stage renal disease, early identification of patients with a renal risk is important. Novel biomarkers may aid in improving renal risk stratification. In this review, we first focus on the classical panel of albuminuria and estimated glomerular filtration rate as the primary clinical predictors of renal disease and then move our attention to novel biomarkers, primarily concentrating on assay-based multiple/panel biomarkers, proteomics biomarkers and metabolomics biomarkers. We focus on multiple biomarker panels since the molecular processes of renal disease progression in type 2 diabetes are heterogeneous, rendering it unlikely that a single biomarker significantly adds to clinical risk prediction. A limited number of prospective studies of multiple biomarkers address the predictive performance of novel biomarker panels in addition to the classical panel in type 2 diabetes. However, the prospective studies conducted so far have small sample sizes, are insufficiently powered and lack external validation. Adequately sized validation studies of multiple biomarker panels are thus required. There is also a paucity of studies that assess the effect of treatments on novel biomarker panels and determine whether initial treatment-induced changes in novel biomarkers predict changes in long-term renal outcomes. Such studies can not only improve our healthcare but also our understanding of the mechanisms of actions of existing and novel drugs and may yield biomarkers that can be used to monitor drug response. We conclude that this will be an area to focus research on in the future.

Effects of mineralocorticoid receptor antagonists in patients with hypertension and diabetes mellitus: a systematic review and meta-analysis

Blood pressure (BP) control is important to ameliorate cardiovascular events in patients with diabetes mellitus (DM). However, achieving the target BP with a single drug is often difficult. The objective of this study was to evaluate the antihypertensive effects of mineralocorticoid receptor antagonists (MRAs) as add-on therapy to renin–angiotensin system (RAS) inhibitor(s) in patients with hypertension and DM. Studies were searched through October 2014 in MEDLINE, Embase and the Cochrane Central Register of Controlled Trials. Randomized, controlled trials or prospective, observational studies regarding concomitant administration of MRA and RAS inhibitor(s) in patients with DM were included. Articles were excluded if the mean systolic BP (SBP) was <130 mm Hg before randomization for interventional studies or at baseline for prospective cohort studies. We identified nine eligible studies (486 patients): five randomized placebo-controlled trials; three randomized active drug-controlled trials; and one single-arm observational study. The mean differences in office SBP and diastolic BP (DBP) between the MRA and placebo groups were −9.4 (95% confidence interval (CI) −12.9 to −5.9) and −3.8 (95% CI, −5.5 to −2.2) mm Hg, respectively. Subgroup analysis results for study type, age, baseline office SBP and follow-up duration were similar to those of the main analysis. MRA mildly increased serum potassium (0.4 mEq l⁻¹; 95% CI, 0.3–0.5 mEq l⁻¹). A consistent reduction of albuminuria across these studies was also demonstrated. MRA further reduced SBP and DBP in patients with hypertension and DM already taking RAS inhibitors. Serum potassium levels should be monitored to prevent hyperkalemia.

Modulation of Immunity and Inflammation by the Mineralocorticoid Receptor and Aldosterone

The mineralocorticoid receptor (MR) is a ligand dependent transcription factor. MR has been traditionally associated with the control of water and electrolyte homeostasis in order to keep blood pressure through aldosterone activation. However, there is growing evidence indicating that MR expression is not restricted to vascular and renal tissues, as it can be also expressed by cells of the immune system, where it responds to stimulation or antagonism, controlling immune cell function. On the other hand, aldosterone also has been associated with proinflammatory immune effects, such as the release of proinflammatory cytokines, generating oxidative stress and inducing fibrosis. The inflammatory participation of MR and aldosterone in the cardiovascular disease suggests an association with alterations in the immune system. Hypertensive patients show higher levels of proinflammatory mediators that can be modulated by MR antagonism. Although these proinflammatory properties have been observed in other autoimmune and chronic inflammatory diseases, the cellular and molecular mechanisms that mediate these effects remain unknown. Here we review and discuss the scientific work aimed at determining the immunological role of MR and aldosterone in humans, as well as animal models.

Spironolactone Add-on for Preventing or Slowing the Progression of Diabetic Nephropathy: A Meta-analysis

PURPOSE

The aim of this meta-analysis was to evaluate the benefits and potential adverse effects of adding spironolactone to standard antidiabetic/renoprotective/antihypertensive (AD/RP/AHT) treatment in patients with diabetic nephropathy (DN).

METHODS

PubMed/MEDLINE and Web of Knowledge were searched for relevant randomized, controlled studies (RCTs) or quasi-RCTs of the effects of adding spironolactone to standard AD/RP/AHT treatment in patients with DN. Results were summarized with a random-effects model or a fixed-effects model.

FINDINGS

According to the outcomes measured (benefits and risks of adding spironolactone to standard AD/RP/AHT treatment), compared with controls, the addition of spironolactone significantly decreased end-of-treatment (EOT) 24-hour urinary albumin/protein excretion and significantly increased percentage reduction from baseline in urinary albumin/creatinine ratio (UACR), although it did not significantly affect EOT UACR. The addition of spironolactone further led to a significantly greater reduction from baseline in glomerular filtration rate (GFR)/estimated (e) GFR, although it did not significantly affect EOT GFR/eGFR. Further, the addition of spironolactone significantly reduced EOT in-office, 24-hour, and daytime systolic and diastolic blood pressure (SBP and DBP, respectively) and led to significantly greater reductions from baseline in in-office SBP and DBP, although it did not significantly affect nighttime SBP or DBP. Finally, the addition of spironolactone significantly increased mean serum/plasma potassium levels and the risk for hyperkalemia.

IMPLICATIONS

Spironolactone could be added to preexisting AD/RP/AHT therapy in patients with DN to prevent or slow DN progression by reducing proteinuria. The addition of spironolactone would likely provide even more beneficial effect in patients with DN and hypertension due to the BP reduction associated with spironolactone use. However, the beneficial effects of spironolactone add-on should be weighed against its potential risks, especially hyperkalemia. The long-term effects of spironolactone add-on on renal outcomes and mortality need to be studied.

Cardiovascular actions of mineralocorticoid receptor antagonists in patients with chronic kidney disease: A systematic review and meta-analysis of randomized trials

INTRODUCTION

The safety and actions of mineralocorticoid receptor antagonists on surrogate markers of cardiovascular disease as well as major patient level cardiovascular end-points in patients with chronic kidney disease are unclear.

METHODS

MEDLINE, EMBASE, Trip Database, Cochrane Central Register of Controlled Trials, Cochrane Renal Group specialized register, Current Controlled Trials and clinicaltrials.gov were searched for relevant trials.

RESULTS

Twenty-nine trials (1581 patients) were included. Overall, mineralocorticoid receptor antagonists lowered both systolic and diastolic blood pressure (-5.24, 95% confidence interval (CI) -8.65, -1.82 mmHg; p=0.003 and -1.96, 95% CI -3.22, -0.69 mmHg; p=0.002 respectively). There were insufficient data to perform a meta-analysis of other cardiovascular effects. However, a systematic review of the studies included suggested a consistent improvement in surrogate markers of cardiovascular disease. Overall, the use of mineralocorticoid receptor antagonists was associated with an increased serum potassium (0.23, 95% CI 0.13, 0.33 mmol/l; p<0.0001) and higher risk ratio (1.76, 95% CI 1.20, 2.57; p=0.001) of hyperkalemia. Data on long-term cardiovascular outcomes and mortality were not available in any of the trials.

CONCLUSIONS

The long-term effects of mineralocorticoid receptor antagonists on cardiovascular events, mortality and safety need to be established.

NT-proBNP, C-reactive protein and soluble uPAR in a bi-ethnic male population: the SAfrEIC study

Objective and design

This cross-sectional study aimed to investigate associations between a marker of cardiac strain, the N-terminal prohormone B-type natriuretic peptide (NT-proBNP), and inflammation as reflected by either a conventional or novel inflammatory marker in a bi-ethnic South African cohort.

Methods and subjects

We measured NT-proBNP, C-reactive protein (CRP) and plasma-soluble urokinase plasminogen activator receptor (suPAR) levels along with conventional biomarkers in black (n = 117) and white (n = 116) men.

Results

NT-proBNP, CRP and suPAR levels were higher in black compared to white men. NT-proBNP was significantly associated with both CRP (r = 0.38; p = 0.001) and suPAR (r = 0.42; p<0.001) in black men only. After full adjustment in multiple regression analyses, the above associations of NT-proBNP with CRP (β = 0.199; p = 0.018) and suPAR (β = 0.257; p<0.01) were confirmed in black men.

Conclusion

These results suggest that a low-grade inflammatory state as reflected by both a conventional and novel marker of inflammation may contribute to higher cardiovascular risk as reflected by the associations obtained with a marker of cardiac strain in black South African men.