Association of the Triglyceride-Glucose Index With Resistant Hypertension and a Nomogram Model Construction

BACKGROUND

Resistant hypertension (RH) remains one of the major risk factors for cardiovascular disease. This study aims to investigate the association between the triglyceride-glucose (TyG) index and RH incidence in patients with hypertension and to construct a nomogram for predicting the occurrence of RH.

METHODS AND RESULTS

A retrospective cohort study was conducted on 1635 patients initially diagnosed with hypertension at the Affiliated Traditional Chinese Medicine Hospital of Xinjiang Medical University from August 2019 to August 2021. Patients were followed up for a median of 31 months, with 373 cases (22.81%) developing RH. Least absolute shrinkage and selection operator regression and multivariable Cox regression analysis identified the TyG index as the strongest predictor of RH (hazard ratio, 5.472 [95% CI, 4.028-7.433]; P<0.001). Consistent results were also observed in subgroup analyses across different ages and sexes. In addition to the TyG index, other independent risk factors, including uric acid, age, and the apnea-hypopnea index, were noted. A nomogram model was subsequently developed using these risk factors, and including the TyG index notably enhanced the diagnostic effectiveness of the model in predicting the occurrence of RH.

CONCLUSIONS

The TyG index appears to be a potential predictor of RH in patients with hypertension, indicating that insulin resistance might be an important factor in the development and progression of RH.

Etiology of Drug-Induced Edema: A Review of Dihydropyridine, Thiazolidinedione, and Other Medications Causing Edema

Edema is an accumulation of fluid in the body's tissues that affects millions of Americans yearly. It can affect multiple body parts, for example, the brain or eyes, but often occurs in the periphery, including the feet and legs. Medications, such as dihydropyridine and thiazolidinediones (TZDs), can be the etiology of edema. Edema can develop in association with problems in the vasculature or lymphatic flow. In recent years, a better understanding of these drug-induced mechanisms has been appreciated. Specifically, dihydropyridines can increase hydrostatic pressure and cause selective pre-capillary vessel vasodilation. TZDs can cause edema through increased vascular permeability and increased hydrostatic pressure. Specifically, peroxisome proliferator-activated receptor gamma (PPARγ) stimulation increases vascular endothelial permeability, vascular endothelial growth factor (VEGF) secretion, renal sodium, and fluid retention. Other drugs that can cause edema include neuropathic pain agents, dopamine agonists, antipsychotics, nitrates, nonsteroidal anti-inflammatory (NSAIDS), steroids, angiotensin-converting enzyme (ACE) inhibitors, and insulin. There are various clinical presentations of edema. Since multiple mechanisms can induce edema, it is important to understand the basic mechanisms and pathophysiology of drug-induced edema. Edema can even become fatal. For example, angioedema can occur from ACE inhibitor therapy. In this regard, it is considered a medical emergency when there is laryngeal involvement. This review aims to thoroughly appreciate the multiple causes of drug-induced edema and the ways it can be treated or prevented.

Therapeutic management of congenital forms of endocrine hypertension

Congenital forms of endocrine hypertension are rare and potentially life-threatening disorders, primarily caused by genetic defects affecting adrenal steroid synthesis and activation pathways. These conditions exhibit diverse clinical manifestations, which can be distinguished by their unique molecular mechanisms and steroid profiles. Timely diagnosis and customized management approach are crucial to mitigate unfavorable outcomes associated with uncontrolled hypertension and other related conditions. Treatment options for these disorders depend on the distinct underlying pathophysiology, which involves specific pharmacological therapies or surgical adrenalectomy in some instances. This review article summarizes the current state of knowledge on the therapeutic management of congenital forms of endocrine hypertension, focusing on familial hyperaldosteronism (FH), congenital adrenal hyperplasia, apparent mineralocorticoid excess, and Liddle syndrome. We provide an overview of the genetic and molecular pathogenesis underlying each disorder, describe the clinical features, and discuss the various therapeutic approaches available and their risk of adverse effects, aiming to improve outcomes in patients with these rare and complex conditions.

Aldosterone activates ERK phosphorylation in the nucleus tractus solitarius

Sodium intake effect of aldosterone has attracted much attention. In our recent study, aldosterone can play a nongenomic regulatory role on rapid sodium intake in the NTS (nucleus tractus solitarius) by activating G protein-coupled estrogen receptor (GPER), and it exhibited an obvious time-dependent and concentration-dependent regulation. However, the molecular mechanism how aldosterone regulated sodium intake rapidly, is unclear. To determine the molecular mechanism of rapid sodium intake regulation of aldosterone, rats with a stainless-steel cannula in the NTS were used (n = 6 each subgroup), and were injected different concentrations of aldosterone/G1 (GPER agonist)/G15 (GPER antagonist) at different time points, then detected ERK1/2 protein expression. The results showed that aldosterone/G1 increased the ERK1/2 protein phosphorylation, and presented a time-dependent and concentration-dependent similar to sodium intake; Meanwhile, G15 partially blocked this effect at least. Taken together, we postulate that ERK1/2 protein may influence nongenomic sodium intake regulated by aldosterone at nucleus tractus solitarius level.

N-/T-Type vs. L-Type Calcium Channel Blocker in Treating Chronic Kidney Disease: A Systematic Review and Meta-Analysis

Renin-angiotensin system (RAS) inhibitors and calcium channel blockers (CCB) are often used together in chronic kidney disease (CKD). The PubMed, EMBASE, and Cochrane Library databases were searched to identify randomized controlled trials (RCTs) in order to explore better subtypes of CCB for the treatment of CKD. This meta-analysis of 12 RCTs with 967 CKD patients who were treated with RAS inhibitors demonstrated that, when compared with L-type CCB, N-/T-type CCB was superior in reducing urine albumin/protein excretion (SMD, −0.41; 95% CI, −0.64 to −0.18; p < 0.001) and aldosterone, without influencing serum creatinine (WMD, −3.64; 95% CI, −11.63 to 4.35; p = 0.37), glomerular filtration rate (SMD, 0.06; 95% CI, −0.13 to 0.25; p = 0.53), and adverse effects (RR, 0.95; 95% CI, 0.35 to 2.58; p = 0.93). In addition, N-/T-type CCB did not decrease the systolic blood pressure (BP) (WMD, 0.17; 95% CI, −1.05 to 1.39; p = 0.79) or diastolic BP (WMD, 0.64; 95% CI, −0.55 to 1.83; p = 0.29) when compared with L-type CCB. In CKD patients treated with RAS inhibitors, N-/T-type CCB is more effective than L-type CCB in reducing urine albumin/protein excretion without increased serum creatinine, decreased glomerular filtration rate, and increased adverse effects. The additional benefit is independent of BP and may be associated with decreased aldosterone (PROSPERO, CRD42020197560).

Atractylenolide-I covalently binds to CYP11B2, selectively inhibits aldosterone synthesis, and improves hyperaldosteronism

Hyperaldosteronism is a common disease that is closely related to endocrine hypertension and other cardiovascular diseases. Cytochrome P450 11B2 (CYP11B2), an important enzyme in aldosterone (ALD) synthesis, is a promising target for the treatment of hyperaldosteronism. However, selective inhibitors targeting CYP11B2 are still lacking due to the high similarity with CYP11B1. In this study, atractylenolide-I (AT-I) was found to significantly reduce the production of ALD but had no effect on cortisol synthesis, which is catalyzed by CYP11B1. Chemical biology studies revealed that due to the presence of Ala320, AT-I is selectively bound to the catalytic pocket of CYP11B2, and the C8/C9 double bond of AT-I can be epoxidized, which then undergoes nucleophilic addition with the sulfhydryl group of Cys450 in CYP11B2. The covalent binding of AT-I disrupts the interaction between heme and CYP11B2 and inactivates CYP11B2, leading to the suppression of ALD synthesis; AT-I shows a significant therapeutic effect for improving hyperaldosteronism.

The paradoxical effect of aldosterone on cardiovascular outcome in maintenance hemodialysis patients

Background

Patients with end-stage kidney disease face increased risk of cardiovascular events, and left ventricular diastolic dysfunction (LVDD) contributes to the high occurrence of cardiovascular mortality (CM). Although a high serum aldosterone (sALD) level is involved in the development of cardiovascular complications in the general population, this association is unclear in patients undergoing hemodialysis. We aimed to determine the impact of sALD on LVDD and CM among hemodialysis patients (HDPs).

Methods

We performed a prospective cohort study of maintenance HDPs without cardiovascular disease. The patients were divided into two groups according to the median level of sALD. All patients underwent baseline echocardiography to evaluate diastolic dysfunction (E/e´ ratio > 15). The LVDD and CM rates were compared between the high and low aldosterone groups.

Results

We enrolled a total of 60 adult patients (mean age, 57.9 ± 12.1 years; males, 30.0%). The low aldosterone group had an increased left ventricular diastolic dimension compared with the high aldosterone group (52.2 ± 8.4 mm vs. 50.3 ± 5.2 mm, respectively; p = 0.03). Low log-aldosterone (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.19-0.86) and large left atrial dimension (OR, 1.31; 95% CI, 1.11-1.54) were independent risk factors for LVDD at baseline. In addition, Cox regression analysis demonstrated that low sALD was an independent predictor of CM in HDPs (hazard ratio, 0.46; 95% CI, 0.25-0.85; p = 0.01) during follow-up.

Conclusion

Low sALD was not only associated with LVDD but was also an independent predictor of CM among HDPs regardless of their interdialytic weight gain.

Role of Oxidative Stress and Reduced Endogenous Hydrogen Sulfide in Diabetic Nephropathy

Purpose

Persistent hyperglycemia lead towards depletion of hydrogen sulfide (H₂S) resulting in generation of oxidative stress and diabetic nephropathy. The aim of the current study was to explore the antioxidant potential of H₂S and captopril, a -SH containing compound in streptozotocin (STZ)-induced diabetic nephropathy.

Methods

Fifty four Wistar-Kyoto (WKY) rats male (200-250g) were divided into nine groups (n=6) with each group injected once with STZ (60mg/kg i.p) except normal control. After 3 weeks of induction of diabetes, groups were assigned as normal control, diabetic control, diabetic-captopril, diabetic-NaHS, diabetic-captopril-NaHS, diabetic-spironolactone, diabetic-metformin, diabetic-metformin-NaHS and diabetic-vitamin-c. All the animals were served with normal saline (N/S 4mL/kg p.o), captopril (50mg/kg/day p.o), sodium hydrosulfide (NaHS) (56µmol/kg i.p), spironolactone (50mg/kg/day s.c), metformin (500mg/kg/day p.o) and vitamin-c (50mg/kg p.o) on daily basis for next 4 weeks, respectively. Metabolic studies, H₂S levels, renal hemodynamics and oxidative stress markers were analyzed at 0, 14 and 28 days followed by histopathological analysis of renal tissues.

Results

The results showed decreased H₂S levels, body weight, sodium to potassium ratio, glutathione (GSH), superoxide dismutase (SOD), total antioxidant assay (T-AOC) with malondialdehyde (MDA) and blood glucose levels significantly increased among diabetic rats. Treatment with captopril, NaHS, metformin, spironolactone and vitamin C showed significant improvement among renal hemodynamics and oxidative stress markers, respectively. But treatment groups like NaHS in combination with captopril and metformin showed more pronounced effects.

Conclusion

The observations suggest that H₂S mediated protective effects on STZ-induced diabetic nephropathy may be associated with reduced oxidative stress via augmenting the antioxidant effect.

SGLT2 Inhibitors and Other Novel Therapeutics in the Management of Diabetic Kidney Disease

Over the past 40 years there has been a steady rise in the number of people with chronic kidney disease due mainly to a significant increase in the number of people with diabetic kidney disease (DKD). Current treatments (blood pressure control, blood sugar control, and renin-angiotensin-aldosterone system inhibitors) have had a significant impact on slowing progression of DKD. But the continued rise illustrates that there is a great need for new medications. Recently, a number of potentially reno-protective medicines have been studied. In this review, these new medications are discussed with respect to both their reported benefits and possible risks.

Blockade of mineralocorticoid receptor ameliorates oral contraceptive-induced insulin resistance by suppressing elevated uric acid and glycogen synthase kinase-3 instead of circulating mineralocorticoid

Context: Estrogen-progestin combined oral contraceptive (COC) has been connected to mineralocorticoid receptor (MR) activation and adverse cardiometabolic events. We consequently hypothesised that insulin resistance (IR), hyperuricemia, and elevated circulating GSK-3 induced by COC is through activation of MR via mineralocorticoid and glucocorticoid pathways.Methods: Female Wistar rats aged 12 weeks received (po) vehicle and COC (1.0 μg ethinylestradiol plus 5.0 μg levonorgestrel) with or without MR blocker (0.25 mg/kg spironolactone; Spl), daily for eight weeks.Results: Data showed that COC treatment led to increased IR, 1-hour postload glucose level, insulinemia, triglyceride/HDL-cholesterol ratio, total cholesterol/HDL-cholesterol ratio, uric acid, GSK-3, aldosterone, corticosterone values, impaired glucose tolerance and pancreatic β-cell function. However, MR blockade by Spl ameliorated all these alterations except that of aldosterone.Conclusion: The results demonstrate that COC induces IR, hyperuricemia and high GSK-3 levels through activation of MR via glucocorticoid dependent pathway.

Aldosterone Jeopardizes Myocardial Insulin and β-Adrenergic Receptor Signaling via G Protein-Coupled Receptor Kinase 2

Hyperaldosteronism alters cardiac function, inducing adverse left ventricle (LV) remodeling either via increased fibrosis deposition, mitochondrial dysfunction, or both. These harmful effects are due, at least in part, to the activation of the G protein-coupled receptor kinase 2 (GRK2). In this context, we have previously reported that this kinase dysregulates both β-adrenergic receptor (βAR) and insulin (Ins) signaling. Yet, whether aldosterone modulates cardiac Ins sensitivity and βAR function remains untested. Nor is it clear whether GRK2 has a role in this modulation, downstream of aldosterone. Here, we show in vitro, in 3T3 cells, that aldosterone impaired insulin signaling, increasing the negative phosphorylation of insulin receptor substrate 1 (^ser307pIRS1) and reducing the activity of Akt. Similarly, aldosterone prevented the activation of extracellular signal-regulated kinase (ERK) and the production of cyclic adenosine 3′,5′-monophosphate (cAMP) in response to the β₁/β₂AR agonist, isoproterenol. Of note, all of these effects were sizably reduced in the presence of GRK2-inhibitor CMPD101. Next, in wild-type (WT) mice undergoing chronic infusion of aldosterone, we observed a marked GRK2 upregulation that was paralleled by a substantial β1AR downregulation and augmented ^ser307pIRS1 levels. Importantly, in keeping with the current in vitro data, we found that aldosterone effects were wholly abolished in cardiac-specific GRK2-knockout mice. Finally, in WT mice that underwent 4-week myocardial infarction (MI), we observed a substantial deterioration of cardiac function and increased LV dilation and fibrosis deposition. At the molecular level, these effects were associated with a significant upregulation of cardiac GRK2 protein expression, along with a marked β1AR downregulation and increased ^ser307pIRS1 levels. Treating MI mice with spironolactone prevented adverse aldosterone effects, blocking GRK2 upregulation, and thus leading to a marked reduction in cardiac ^ser307pIRS1 levels while rescuing β1AR expression. Our study reveals that GRK2 activity is a critical player downstream of the aldosterone signaling pathway; therefore, inhibiting this kinase is an attractive strategy to prevent the cardiac structural disarray and dysfunction that accompany any clinical condition accompanied by hyperaldosteronism.

Medical complications of bulimia nervosa

Bulimia nervosa is a psychiatric disorder with many different medical sequelae. This article reviews the principal medical complications associated with bulimia nervosa, and emphasizes the importance of a timely approach to diagnosis and management.

Hypertension in Childhood Nephrotic Syndrome

Arterial hypertension (HTN) is commonly encountered by clinicians treating children with steroid sensitive (SSNS) and steroid resistant nephrotic syndrome (SRNS). Although the prevalence of HTN in SSNS is less documented than in SRNS, recent studies reported high prevalence in both. Studies have estimated the prevalence of HTN in different patient populations with NS to range from 8 to 59.1%. Ambulatory HTN, abnormalities in BP circadian rhythm, and measures of BP variability are prevalent in patients with NS. Multiple mechanisms and co-morbidities contribute to the pathophysiology of HTN in children with NS. Some contributing factors are known to cause acute and episodic elevations in blood pressure such as fluid shifts, sodium retention, and medication side effects (steroids, CNIs). Others are associated with chronic and more sustained HTN such as renal fibrosis, decreased GFR, and progression of chronic kidney disease. Children with NS are more likely to suffer from other cardiovascular disease risk factors, such as obesity, increased measures of arterial stiffness [increased carotid intima-media thickness (cIMT), endothelial dysfunction, increased pulse wave velocity (PWV)], impaired glucose metabolism, dyslipidemia, left ventricular hypertrophy (LVH), left ventricular dysfunction, and atherosclerosis. Those risk factors have been associated with premature death in adults. In this review on HTN in patients with NS, we will discuss the epidemiology and pathophysiology of hypertension in patients with NS, as well as management aspects of HTN in children with NS.

Aldosterone and Mineralocorticoid Receptor System in Cardiovascular Physiology and Pathophysiology

The mineralocorticoid hormone aldosterone (Aldo) has been intensively studied for its ability to influence both the physiology and pathophysiology of the cardiovascular system. Indeed, although research on Aldo actions for decades has mainly focused on its effects in the kidney, several lines of evidence have now demonstrated that this hormone exerts disparate extrarenal adverse effects, especially in the circulatory system. Accordingly, in the last lusters, a number of studies in preclinical models (in vitro and in vivo) and in humans have established that Aldo, following the interaction with its receptor-the mineralocorticoid receptor (MR)-is able to activate specific intracellular genomic and nongenomic pathways, thus regulating the homeostasis of the cardiovascular system. Importantly, through this mechanism of action, this hormone becomes a crucial regulator of the function and growth of different types of cells, including fibroblasts, cardiomyocytes, and vascular cells. For this main reason, it is plausible that when Aldo is present at high levels in the blood, it profoundly modifies the physiology of these cells, therefore being at the foundation of several cardiovascular disorders, such as heart failure (HF). On these grounds, in this review, we will provide an updated account on the current knowledge concerning Aldo activity in the cardiovascular system and the most recent preclinical studies and clinical trials designed to test better approaches able to counter the hyperactivity of the Aldo/MR signaling pathway in the setting of cardiovascular diseases.

Lipocalin-2 derived from adipose tissue mediates aldosterone-induced renal injury

Lipocalin-2 is not only a sensitive biomarker, but it also contributes to the pathogenesis of renal injuries. The present study demonstrates that adipose tissue-derived lipocalin-2 plays a critical role in causing both chronic and acute renal injuries. Four-week treatment with aldosterone and high salt after uninephrectomy (ANS) significantly increased both circulating and urinary lipocalin-2, and it induced glomerular and tubular injuries in kidneys of WT mice. Despite increased renal expression of lcn2 and urinary excretion of lipocalin-2, mice with selective deletion of lcn2 alleles in adipose tissue (Adipo-LKO) are protected from ANS- or aldosterone-induced renal injuries. By contrast, selective deletion of lcn2 alleles in kidney did not prevent aldosterone- or ANS-induced renal injuries. Transplantation of fat pads from WT donors increased the sensitivity of mice with complete deletion of Lcn2 alleles (LKO) to aldosterone-induced renal injuries. Aldosterone promoted the urinary excretion of a human lipocalin-2 variant, R81E, in turn causing renal injuries in LKO mice. Chronic treatment with R81E triggered significant renal injuries in LKO, resembling those observed in WT mice following ANS challenge. Taken in conjunction, the present results demonstrate that lipocalin-2 derived from adipose tissue causes acute and chronic renal injuries, largely independent of local lcn2 expression in kidney.

Evaluation of laboratory disturbance risk when adding low-dose cotrimoxazole for PJP prophylaxis to regimens of high-grade glioma patients taking RAAS inhibitors

BACKGROUND

Cotrimoxazole is associated with the development of hyponatremia, hyperkalemia and elevated serum creatinine, especially when combined with inhibitors of the renin-angiotensin-aldosterone system (RAAS). Pneumocystis jirovecii pneumonia (PJP) prophylaxis is the standard of care for high-grade glioma (HGG) patients receiving temozolomide concurrently with radiotherapy, low-dose cotrimoxazole being the preferred agent. Many of these patients are also taking renin-angiotensin-aldosterone system inhibitors, however the risk of significant laboratory disturbance in these patients remains undescribed.

OBJECTIVE

We evaluated whether high-grade glioma patients taking renin-angiotensin-aldosterone system inhibitors receiving low-dose cotrimoxazole for Pneumocystis jirovecii pneumonia prophylaxis are at additional risk of laboratory disturbances in comparison with their non-renin-angiotensin-aldosterone system counterparts.

METHODS

We conducted a retrospective chart review of adult neuro-oncology patients treated for WHO Grade III or IV glioma between 2013 and 2016. Patient serum Na, K, creatinine, and eGFR were compared (renin-angiotensin-aldosterone system vs. non-renin-angiotensin-aldosterone system) using the chi-square test. Binary logistic regression analysis was then performed to account for differences between cohorts.

RESULTS

Of 63 patients (35 non-renin-angiotensin-aldosterone system, 28 renin-angiotensin-aldosterone system), patients in the renin-angiotensin-aldosterone system cohort were more likely to experience a laboratory disturbance (odds ratio=3.17, p = 0.03). Overall, these disturbances were moderate, but were slightly more common and slightly more severe in the renin-angiotensin-aldosterone system cohort.

CONCLUSION

Adding low-dose cotrimoxazole for Pneumocystis jirovecii pneumonia prophylaxis to the regimens of patients with high-grade glioma taking renin-angiotensin-aldosterone system inhibitors increases the risk of laboratory disturbances. While these are generally moderate, some patients are at risk of significant electrolyte abnormalities requiring intervention.

Medical findings in 1,026 consecutive adult inpatient-residential eating disordered patients

OBJECTIVE

Eating disorders are associated with multiple medical complications. We report contemporary medical data, for newly admitted adult inpatient and residential level of care patients.

METHOD

Medical records of a transdiagnostic sample of 1,026 patients, with eating disorders, were retrospectively reviewed for the presence of a broad array of medical complications at time of admission. The prevalence of physiologically relevant medical complications was assessed across major eating disorder categories.

RESULTS

Of the patients, 93.6% were female, and they had an average age of 28.1 (SD = 10.1, range 17-69). The average admission body mass index was 16.1 (SD = 2.3). The prevalence of abnormal laboratory values varied by eating disorder subtype. In patients with anorexia nervosa-restricting subtype, 51.4% had low prealbumin, 36.1% were leukopenic, 34.3% had osteoporosis, 30.0% vitamin D deficiency, 16.8% metabolic alkalosis, 16.0% had hyponatremia, 14.2% hypokalemia, and 7.1% hypoglycemia. These patients had normal average QTc intervals. In patients with anorexia nervosa-binge purging subtype, 42.4% had hypokalemia, 33.3% metabolic alkalosis, osteoporosis in 21.1%, and they had longer QTc intervals (433.9 ms, p < .001). Only 6.0% of patients with anorexia nervosa had hypophosphatemia. Patients with bulimia nervosa demonstrated hypokalemia in 26.2%, and metabolic alkalosis in 23.4%; the QTc interval was longer than in AN-R patients (437.9 ms, p < .001), but still in the normal range.

DISCUSSION

Numerous medical complications are associated with severe eating disorders. As the severity increases, the number of complications increase and are related to the presence or absence of purging behaviors.

Elevated FGF23 Levels in Mice Lacking the Thiazide-Sensitive NaCl cotransporter (NCC)

Fibroblast growth factor 23 (FGF23) participates in the orchestration of mineral metabolism by inducing phosphaturia and decreasing the production of 1,25(OH)₂D₃. It is known that FGF23 release is stimulated by aldosterone and extracellular volume depletion. To characterize this effect further in a model of mild hypovolemia, we studied mice lacking the thiazide sensitive NaCl cotransporter (NCC). Our data indicate that NCC knockout mice (KO) have significantly higher FGF23, PTH and aldosterone concentrations than corresponding wild type (WT) mice. However, 1,25(OH)₂D₃, fractional phosphate excretion and renal brush border expression of the sodium/phosphate co-transporter 2a were not different between the two genotypes. In addition, renal expression of FGF23 receptor FGFR1 and the co-receptor Klotho were unaltered in NCC KO mice. FGF23 transcript was increased in the bone of NCC KO mice compared to WT mice, but treatment of primary murine osteoblasts with the NCC inhibitor hydrochlorothiazide did not elicit an increase of FGF23 transcription. In contrast, the mineralocorticoid receptor blocker eplerenone reversed excess FGF23 levels in KO mice but not in WT mice, indicating that FGF23 upregulation in NCC KO mice is primarily aldosterone-mediated. Together, our data reveal that lack of renal NCC causes an aldosterone-mediated upregulation of circulating FGF23.

Overexpressed cyclophilin B suppresses aldosterone-induced proximal tubular cell injury both in vitro and in vivo

The renin-angiotensin-aldosterone system (RAAS) is overactivated in patients with chronic kidney disease. Oxidative stress and endoplasmic reticulum stress (ERS) are two major mechanisms responsible for aldosterone-induced kidney injury. Cyclophilin (CYP) B is a chaperone protein that accelerates the rate of protein folding through its peptidyl-prolyl cis-trans isomerase (PPIase) activity. We report that overexpression of wild-type CYPB attenuated aldosterone-induced oxidative stress (evidenced by reduced production of reactive oxygen species and improved mitochondrial dysfunction), ERS (indicated by reduced expression of the ERS markers glucose-regulated protein 78 [GRP78] and C/-EBP homologous protein [CHOP]), and tubular cell apoptosis in comparison with aldosterone-induced human kidney-2 (HK-2) cells. The in vivo study also yielded similar results. Hence, CYPB performs a crucial function in protecting cells against aldosterone-induced oxidative stress, ERS, and tubular cell injury via its PPIase activity.

Sodium Homeostasis in Chronic Kidney Disease

The pathologic consequences of sodium retention in the CKD population can lead to hypertension, edema, and progressive disease. Sodium excess is responsible for increases in oxidative stress, which alters kidney vasculature. As progression of CKD occurs, hyperfiltration by remaining nephrons compensates for an overall decrease in the filtered load of sodium. In the later stages of CKD, compensatory mechanisms are overcome and volume overload ensues. Nephrotic syndrome as it relates to sodium handling involves a different pathophysiology despite a common phenotype. Extrarenal sodium buffering is also examined as it has significant implications in the setting of advanced CKD.

Synthetic approaches towards the multi target drug spironolactone and its potent analogues/derivatives

Spironolactone is a well-known multi-target drug and is specifically used for the treatment of high blood pressure and heart failure. It is also used for the treatment of edema, cirrhosis of the liver, malignant, pediatric, nephrosis and primary hyperaldosteronism. Spironolactone in association with thiazide diuretics treats hypertension and in association with furosemide treats bronchopulmonary dyspepsia. The therapeutic mechanism of action of spironolactone involves binding to intracellular mineralocorticoids receptors (MRs) in kidney epithelial cells, thereby inhibiting the binding of aldosterone. Since its first synthesis in 1957 there are several synthetic approaches have been reported throughout the years, Synthetic community has devoted efforts to improve the synthesis of spironolactone and to synthesize its analogues and derivatives. This review aims to provide comprehensive insight for the synthetic endeavors devoted towards the synthesis of a versatile drug spironolactone and its analogues/derivatives.

NLRP3 inflammasome activation contributes to aldosterone-induced podocyte injury

Aldosterone (Aldo) has been shown as an important contributor of podocyte injury. However, the underlying molecular mechanisms are still elusive. Recently, the pathogenic role of NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome in mediating renal tubular damage was identified while its role in podocyte injury still needs evidence. Thus the present study was undertaken to investigate the role of NLRP3 inflammasome in Aldo-induced podocyte damage. In vitro, exposure of podocytes to Aldo enhanced NLRP3, caspase-1, and IL-18 expressions in dose- and time-dependent manners, indicating an activation of NLRP3 inflammasome, which was significantly blocked by the mineralocorticoid receptor antagonist eplerenone or the antioxidant N-acetylcysteine. Silencing NLRP3 by a siRNA approach strikingly attenuated Aldo-induced podocyte apoptosis and nephrin protein downregulation in line with the blockade of caspase-1 and IL-18. In vivo, since day 5 of Aldo infusion, NLRP3 inflammasome activation and podocyte injury evidenced by nephrin reduction occurred concurrently. More importantly, immunofluorescence analysis showed a significant induction of NLRP3 in podocytes of glomeruli following Aldo infusion. In the mice with NLRP3 gene deletion, Aldo-induced downregulation of nephrin and podocin, podocyte foot processes, and albuminuria was remarkably improved, indicating an amelioration of podocyte injury. Finally, we observed a striking induction of NLRP3 in glomeruli and renal tubules in line with an enhanced urinary IL-18 output in nephrotic syndrome patients with minimal change disease or focal segmental glomerular sclerosis. Together, these results demonstrated an important role of NLRP3 inflammasome in mediating the podocyte injury induced by Aldo.

Autophagy is involved in aldosterone‑induced mesangial cell proliferation

The aim of the present study was to investigate whether autophagy is involved in aldosterone (Aldo)-induced mesangial cell (MC) proliferation. MCs were incubated with 10‑7 M Aldo for 24 h. Proliferation of MCs, and the underlying mechanisms, were subsequently analyzed using [3H]thymidine assay, cell counting assay, western blotting and RNA interference (RNAi). Aldo was revealed to induce autophagy, as indicated by the increased conversion from microtubule‑associated protein 1A/1B‑light chain 3 (LC3)‑I to LC3‑II, the increased expression levels of autophagy‑related gene 7 (Atg7) and the increased degradation of p62, which was accompanied by MC proliferation. Notably, pharmacological inhibition of autophagy or RNAi‑mediated knockdown of Atg7 attenuated Aldo‑induced MC proliferation, suggesting that autophagy was at least partially responsible for this effect. The results of the present study provided evidence that autophagy is critical for regulating Aldo‑induced MC proliferation.

Aldosterone is associated with left ventricular hypertrophy in hemodialysis patients

OBJECTIVES

Patients with chronic kidney disease present a higher degree of left ventricular hypertrophy than expected for hypertension levels. In chronic kidney disease the plot between the quotient extracellular water/total body water and aldosterone is shifted up and to the right. There are few studies that verified the role of aldosterone in cardiac remodeling in this set of patients. The aim of this study was to evaluate the relationship between serum aldosterone and left ventricular mass index in patients with chronic kidney disease on hemodialysis.

METHODS

The patients were submitted to clinical and laboratory evaluation, bioelectrical impedance, echocardiography and ambulatory blood pressure monitoring. The 27 patients included were divided into two groups according to aldosterone level and compared with each other.

RESULTS

The group of patients with higher aldosterone levels had higher left ventricular mass index. These groups were heterogeneous with regard to ambulatory systolic blood pressure, body mass index, and aldosterone levels and homogeneous with regard to the quotient extracellular water/total body water, renin-angiotensin-aldosterone system blockers, beta blocker use and other clinical characteristics. The association between aldosterone levels and left ventricular mass index was adjusted to confounding variables by a multiple linear regression analysis in which aldosterone was independently associated with left ventricular mass index.

CONCLUSION

The data presented are consistent with a pathogenic role of aldosterone in left ventricular hypertrophy in patients with chronic kidney dialysis in dialysis patients.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01128101.

Effective medical treatment strategies to help cessation of purging behaviors

OBJECTIVE

Herein we review the major medical issues involved in the "detoxing" of patients who engage in purging behaviors and the pathophysiology of why they occur.

METHODS

Given a limited evidence base of randomized controlled trials, we conducted a thorough qualitative review to identify salient literature with regard to the medical issues involved in "detoxing" patients from their purging behaviors.

RESULTS

Pseudo Bartter's Syndrome is the root cause of much of the medical difficulties which can arise when purging behaviors are abruptly discontinued. However, this is imminently treatable and even preventable with a judicious medical treatment plan which targets the increased serum aldosterone levels which would otherwise promote salt and water retention and a propensity towards severe edema formation. Effective recommendations are provided which can make this process much less vexing for patients attempting to cease their purging behaviors.

CONCLUSIONS

"Detoxing" from purging behaviors can be fraught with medical complications which frustrate these patients and can lead to unsuccessful outcomes. Medical providers should become familiar with the pathophysiology which is the basis for Pseudo Bartter's Syndrome and the effective medical treatments which can lead to a successful outcome.

Reactive oxygen species-initiated autophagy opposes aldosterone-induced podocyte injury

Evidence has demonstrated that aldosterone (Aldo) is involved in the development and progression of chronic kidney diseases. The purpose of the present study was to investigate the role of autophagy in Aldo-induced podocyte damage and the underlying mechanism. Mouse podocytes were treated with Aldo in the presence or absence of 3-methyladenine and N-acetylcysteine. Cell apoptosis was investigated by detecting annexin V conjugates, apoptotic bodies, caspase-3 activity, and alterations of the podocyte protein nephrin. Autophagy was evaluated by measuring the expressions of light chain 3, p62, beclin-1, and autophagy-related gene 5. Aldo (10^-7 mol/l) induced podocyte apoptosis, autophagy, and downregulation of nephrin protein in a time-dependent manner. Aldo-induced apoptosis was further promoted by the inhibition of autophagy via 3-methyladenine and autophagy-related gene 5 small interfering RNA pretreatment. Moreover, Aldo time dependently increased ROS generation, and H₂O₂ (10^-4 mol/l) application remarkably elevated podocyte autophagy. After treatment with N-acetylcysteine, the autophagy induced by Aldo or H₂O₂ was markedly attenuated, suggesting a key role of ROS in mediating autophagy formation in podocytes. Inhibition of ROS could also lessen Aldo-induced podocyte injury. Taken together, our findings suggest that ROS-triggered autophagy played a protective role against Aldo-induced podocyte injury, and targeting autophagy in podocytes may represent a new therapeutic strategy for the treatment of podocytopathy.

Up-regulation of FGF23 release by aldosterone

The fibroblast growth factor (FGF23) plasma level is high in cardiac and renal failure and is associated with poor clinical prognosis of these disorders. Both diseases are paralleled by hyperaldosteronism. Excessive FGF23 levels and hyperaldosteronism are further observed in Klotho-deficient mice. The present study explored a putative aldosterone sensitivity of Fgf23 transcription and secretion the putative involvement of the aldosterone sensitive serum & glucocorticoid inducible kinase SGK1, SGK1 sensitive transcription factor NFκB and store operated Ca(2+) entry (SOCE). Serum FGF23 levels were determined by ELISA in mice following sham treatment or exposure to deoxycorticosterone acetate (DOCA) or salt depletion. In osteoblastic UMR106 cells transcript levels were quantified by qRT-PCR, cytosolic Ca(2+) concentration utilizing Fura-2-fluorescence, and SOCE from Ca(2+) entry following store depletion by thapsigargin. As a result, DOCA treatment and salt depletion of mice elevated the serum C-terminal FGF23 concentration. In UMR106 cells aldosterone enhanced and spironolactone decreased SOCE. Aldosterone further increased Fgf23 transcript levels in UMR106 cells, an effect reversed by mineralocorticoid receptor blockers spironolactone and eplerenone, SGK1 inhibitor EMD638683, NFκB-inhibitor withaferin A, and Ca(2+) channel blocker YM58483. In conclusion, Fgf23 expression is up-regulated by aldosterone, an effect sensitive to SGK1, NFκB and store-operated Ca(2+) entry.

Mineralocorticoid receptor antagonists as diuretics: Can congestive heart failure learn from liver failure?

Despite significant improvements in diagnosis, understanding the pathophysiology and management of the patients with acute decompensated heart failure (ADHF), diuretic resistance, yet to be clearly defined, is a major hurdle. Secondary hyperaldosteronism is a pivotal factor in pathogenesis of sodium retention, refractory congestion in heart failure (HF) as well as diuretic resistance. In patients with decompensated cirrhosis who suffer from ascites, similar pathophysiological complications have been recognized. Administration of natriuretic doses of mineralocorticoid receptor antagonists (MRAs) has been well established in management of cirrhotic patients. However, this strategy in patients with ADHF has not been well studied. This article will discuss the potential use of natriuretic doses of MRAs to overcome the secondary hyperaldosteronism as an alternative diuretic regimen in patients with HF.

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.

Protective effect of telmisartan on rats with renal failure and its mechanism

OBJECTIVE

To study the protective effect of telmisartan on rats with renal failure and its mechanism.

METHODS

60 Wistar rats were chosen as study objective, and were divided into 4 groups randomly: 15 in group A (sham operation group), 15 in group B (model group), 15 in group C (telmisartan group) and 15 in group D (telmisartan + GW9962 group). The difference of survival rate, blood-urine biochemical indexes, renal pathological change, and the expression level of PPARγ and nNOS were compared.

RESULTS

After 12 weeks, the survival rate of group A was 93.33% (14/15), that of group B was 46.67% (7/15), that of group C was 86.67% (13/15), that of group D was 60.00% (9/15), and the difference among 4 groups had statistical significance (P < 0.05). After 1 week, the difference of Scr, that of BUN and that of 24 h protein urine among 4 groups was not statistical significant (P > 0.05); after 3 weeks, 6 weeks and 12 weeks, these difference was statistical significant (P < 0.05). The difference of blood-urine biochemical indexes, that of renal pathological change, and that of the expression level of PPARγ and nNOS was statistical significant (P < 0.05).

CONCLUSIONS

Telmisartan has protective effect on renal failure caused by 5/6 nephrectomy, which might be relative to the expression level of PPARγ and nNOS.

Aldosterone blockade in CKD: emphasis on pharmacology

Besides its epithelial effect on sodium retention and potassium excretion in the distal tubule, aldosterone promotes inflammation and fibrosis in the heart, kidneys, and blood vessels. As glomerular filtration rate falls, aldosterone is inappropriately elevated relative to extracellular fluid expansion. In addition, studies in CKD patients on angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and/or direct renin inhibitors have shown that aldosterone levels paradoxically rise in approximately 30% to 40% of patients on these renin-angiotensin system-blocking drugs. Hence, there is interest in using mineralocorticoid receptor blockers that directly target the inflammatory and fibrotic effects of aldosterone in CKD patients. This interest, however, is tempered by a number of unresolved issues, including the safety of using such drugs in advanced CKD and ESRD populations, and the potential for differences in drug efficacy according to race and ethnicity of patient populations. A better understanding of mineralocorticoid receptor blocker pharmacology should help inform future research directions and clinical practice decisions as to how best to use these agents in CKD.

Pharmacotherapy and mortality in atrial fibrillation--a cohort of men and women 75 years or older in Sweden

BACKGROUND

Atrial fibrillation (AF) is a common cardiovascular morbidity, not least among elderly people, and is treated with different classes of cardiovascular pharmacotherapies.

HYPOTHESIS

Cardiovascular drugs may have a different impact on survival in elderly patients with AF in primary health care.

METHODS

A cohort of 3,020 men and 3,749 women aged ≥75 and diagnosed with AF were selected from 75 primary care centres in Sweden. Laplace regression was used with years to death of the first 10% of the participants as the outcome. Independent variables were prescribed cardiovascular drugs. Regression models were adjusted for a propensity score comprising age, cardiovascular co-morbidities, socio-economic factors and other cardiovascular pharmacotherapies.

RESULTS

Overall, mortality was 18.2%. The main finding of this study was survival increases associated with anticoagulants versus no treatment and versus antiplatelets of 1.95 years (95% confidence interval (CI) 1.43-2.48) and 0.78 years (95% CI 0.38-1.18), respectively, and survival increases associated with thiazides and calcium channel blockers of 0.81 years (95% CI 0.43-1.18) and 0.83 years (95% CI 0.47-1.18), respectively, in men and women together (results from sex-adjusted models).

CONCLUSION

Our findings suggest that anticoagulants, thiazides and calcium channel blockers may lead to longer survival in elderly patients with AF.

Consensus recommendations for standard therapy of glomerular disease in dogs

Standard therapy forms the basic foundation for care of dogs with glomerular disease, as it is herein recommended for use in all affected animals regardless of causation of the disease. Consensus recommendations target the evaluation and management of proteinuria, inhibition of the renin-angiotensin-aldosterone system, modification in dietary intake with special consideration for those nutrients with renal effects, diagnosis and treatment of systemic hypertension, and evaluation and management of body fluid volume status in dogs with glomerular disease.

[Renal dysfunction in heart failure and hypervolumenia : Importance of congestion and backward failure]

Traditionally, renal dysfunction in congestive heart failure (cardiorenal syndrome type 1) has been attributed to reduced cardiac output and low mean arterial perfusion pressure, which elicit a series of neurohumoral activations resulting in increased renal vascular resistance and decreased renal function.During the last decade, several studies have shown that the extent of renal dysfunction is not so closely associated with indices of forward failure-such as the cardiac index or mean arterial pressure-but rather with indicators of congestion, such as left ventricular enddiasystolic pressure or central venous pressure (CVP), which are indicators of backward failure. The impact of backward failure on renal function is not confined to an elevation of CVP, the renal drainage pressure, but includes a broad spectrum of mechanisms. Involved are the organ systems right heart, lung, the liver, the proinflammatory signals originating from the intestines, but also renal interstitial edema (renal compartment syndrome) and the intraabdominal pressure.The therapeutic measures must focus on the modulation of the preload adapted to the specific situation of an individual patient. This includes diuretics aiming at different segments of the tubulus system including antagonists of aldosteron and ADH, extracorporeal fluid elimination by ultrafiltration or peritoneal dialysis.

Aldosterone blockade in chronic kidney disease

Although blockade of the renin-angiotensin-aldosterone system with angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers has become standard therapy for chronic kidney disease (CKD), renewed interest in the role of aldosterone in mediating the injuries and progressive insults of CKD has highlighted the potential role of treatments targeting the mineralocorticoid receptor (MR). Although salt restriction is an important component of mitigating the profibrotic effects of MR activation, a growing body of literature has shown that MR antagonists, spironolactone and eplerenone, can reduce proteinuria and blood pressure in patients at all stages of CKD. These agents carry a risk of hyperkalemia, but this risk likely can be predicted based on baseline renal function and mitigated using dietary modifications and adjustments of concomitant medications. Data on hard outcomes, such as progression to end-stage renal disease and overall mortality, still are lacking in patients with CKD.

Effects of prescribed antithrombotics and other cardiovascular pharmacotherapies on all-cause mortality in patients with diabetes and atrial fibrillation - a cohort study from Sweden using propensity score analyses

AIMS

To study mortality rates among patients with diabetes and concomitant atrial fibrillation (AF), prescribed different cardiovascular drugs in primary health care.

METHODS

Study population consisted of men (n = 1319) and women (n = 1094) aged ≥45 years from a database including 75 primary care centres in Sweden. Cox regression analysis, with hazard ratios (HRs), 95% confidence interval (95% CIs) and mortality (years to death) as outcome, and Laplace regression, with difference in time to first 10% mortality (with 95% CI), were performed. Independent variables were prescribed cardiovascular drugs. Regression models were adjusted for a propensity score calculated separately for each prescribed drug class (comprising age, cardiovascular co-morbidities, education, marital status and pharmacotherapy).

RESULTS

Overall mortality was lower in the whole sample for anticoagulants vs no treatment (HR 0.45; 95% CI 0.26-0.77); and among patients < 80 years for anticoagulants vs. antiplatelets (HR 0.44; 95% CI 0.25-0.78); while among individuals aged ≥80 years, antiplatelets (HR 0.47; 95% CI 0.26-0.87) and anticoagulants (HR 0.49; 95% CI 0.24-1.00) vs. no treatment were equally effective. Statins were associated with lower mortality among those <80 years (HR 0.45; 95% CI 0.29-0.71). Laplace regression models in the whole sample, with years to first 10% of total mortality as outcome, were significant for: among patients < 80 years anticoagulants vs. no treatment 2.70 years (95% CI 0.04-5.37), anticoagulants vs. antiplatelets 2.31 years (95% CI 0.84-3.79), and those ≥80 antiplatelets vs. no treatment 1.78 years (95% CI 1.04-2.52).

CONCLUSIONS

Our findings suggest that antiplatelets could exert a beneficial effect among those above 80 years.

Long-term effects of addition of mineralocorticoid receptor antagonist to angiotensin II receptor blocker in patients with diabetic nephropathy: a randomized clinical trial

BACKGROUND

Addition of spironolactone (SPR) to angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) might provide antiproteinuric effects beyond what is gained by either medication alone. This study was designed to assess the long-term efficacy of SPR/ARB combination in comparison with the standard ACE/ARB regimen in diabetic nephropathy.

METHODS

In an open-label, parallel-group, single-center, randomized clinical trial (NCT01667614), 136 patients with diabetes and proteinuria, already treated with enalapril and losartan, were included. In 74 patients, ACE inhibitors were discontinued. After a wash-out period of 2 weeks, 25 mg SPR daily was initiated. The remainder of the patients (n = 62) received ACE inhibitors and ARBs as before. Patients were followed every 3 months for 18 months. During each visit, systolic and diastolic blood pressure (BP), urinary albumin excretion (UAE), serum creatinine, estimated glomerular filtration rate (eGFR) and serum potassium concentrations were determined.

RESULTS

After 18 months, three patients in the SPR/ARB group developed asymptomatic hyperkalemia. SPR/ARB significantly reduced both systolic and diastolic BP (P < 0.001 and 0.001, respectively). SPR/ARB decreased UAE by 46, 72 and 59% after 3, 12 and 18 months, respectively. Compared with the continuation regimen, SPR/ARB was superior in UAE reduction (P = 0.017 after 18 months), independent of BP change. In both groups, eGFR declined significantly over the trial course and the decline rate did not differ significantly between the two groups.

CONCLUSIONS

Addition of SPR to ARB provides added benefits with respect to BP control and proteinuria diminution. These antiproteinuric effects are not accompanied by prevention of eGFR loss compared with conventional therapy with ACE/ARB.

Left ventricular geometry in obesity: Is it what we expect?

Obesity is characterized by the disproportionate growth of the components of body size, including adipose tissue and lean body mass. Left ventricular (LV) hypertrophy often develops, due to the coexistence of hemodynamic (cardiac workload) and non-hemodynamic components (including body composition and activity of visceral fat). While the hypertrophy of cardiomyocytes is produced by the hemodynamic load, through sarcomeric replication, there is a parallel growth of non-muscular myocardial components, including interstitial fat infiltration and accumulation of triglycerides in the contractile elements, which are thought to influence LV geometric pattern. Thus, pure intervention on hemodynamic load is unlikely to result in effective reduction of LV hypertrophy in obese. We review pathophysiology and prevalence of LV hypertrophy in obesity, with specific attention to LV geometric abnormalities and relations with body size.

Feline CKD: Pathophysiology and risk factors--what do we know?

PRACTICAL RELEVANCE

Chronic kidney disease (CKD) is one of the most frequently encountered disorders in cats, having increased in prevalence in recent decades. Although the underlying cause is rarely identified, the common final outcome of feline CKD is tubulointerstitial fibrosis. Knowledge of CKD pathophysiology is necessary for optimal individualised patient management, especially with regard to diagnosis and treatment of extrarenal complications.

PATIENT GROUP

CKD is most common in senior and geriatric cats, but should be considered in any feline patient with ureterolithiasis, hyperthyroidism, retrovirus infection, systemic hypertension, cardiovascular disease or urinary tract infection.

EVIDENCE BASE

Most of our knowledge of the pathogenesis of CKD is extrapolated from human nephrology and experimental animal studies. There is, therefore, a need for further studies in cats. The prevalence of clinical signs in feline CKD is well documented. Several concurrent diseases associated with CKD have also been reported in cats, especially in the geriatric population, but there is no or only limited published evidence demonstrating a cause-and-effect relationship between most of these conditions and CKD. Studies performed over the past 15 years have nevertheless allowed identification of major risk factors (proteinuria, plasma phosphate and plasma creatinine) influencing the progression of feline CKD.

CLINICAL CHALLENGES

Clinical signs occur in the late stages of renal disease, so populations at higher risk of CKD should be screened routinely. CKD-associated complications (systemic hypertension, secondary renal hyperparathyroidism, hypokalaemia, anaemia, metabolic acidosis) must not be overlooked as they may affect the progression of disease. Disease progression is itself unpredictable and renal function may remain stable for extended periods. Most cats with early CKD do not progress to end-stage CKD before they die.

AUDIENCE

General practitioners play a major role in screening feline patients at risk of development or progression of CKD.