Diuretics and bioimpedance-measured fluid spaces in hypertensive patients

Angiotensin receptor neprilysin inhibitor as a novel antihypertensive drug: Evidence from Asia and around the globe

Hypertension is a worldwide epidemic that continues to grow, with a subset of patients responding poorly to current treatment available. This is especially relevant in Asia, which constitutes 61% of the global population. Hypertension in Asia is a unique entity that is often salt‐sensitive, nocturnal, and systolic predominant. Sacubitril/valsartan is a first‐in‐class angiotensin receptor neprilysin inhibitor that was first used in heart failure with reduced ejection fraction. Sacubitril inhibits neprilysin, a metallopeptidase that degrades natriuretic peptides (NPs). NPs exert sympatholytic, diuretic, natriuretic, vasodilatory, and insulin‐sensitizing effects mostly via cyclic guanosine monophosphate (cGMP)‐mediated pathways. As an antihypertensive agent, sacubitril/valsartan has outperformed angiotensin II receptor type 1 blockers (ARBs), with additional reductions of office systolic blood pressures ranging between 5 and 7 mmHg, in multiple studies in Asia and around the globe. The drug was well tolerated even in the elderly or those with chronic kidney disease. Its mechanisms of actions are particularly attractive for treatment of hypertension in Asia. Sacubitril/valsartan offers a novel, dual class, single‐molecule property that may be considered as first‐line antihypertensive therapy. Further investigations are needed to validate its safety for long‐term use and to explore other potentials such as in the management of insulin resistance and obesity, which often coexist with hypertension in Asia.

Acute Kidney Injury in Subjects With Chronic Kidney Disease Undergoing Total Joint Arthroplasty

BACKGROUND

Chronic kidney disease (CKD) has been associated with higher incidence of complications after total joint arthroplasty (TJA) but the incidence, risk factors and outcomes of acute kidney injury (AKI) in this setting remains insufficiently understood.

METHODS

We assessed the impact of baseline CKD on the risk of developing AKI after TJA performed between 1/2012 and 12/2016 in a single-center, retrospective cohort study. CKD was defined by estimated glomerular filtration rate <60 mL/min/1.73 m² on 2 separate occasions within 3 months prior TJA. AKI was defined using a modified Kidney Disease: Improving Global Outcomes criteria based on serum creatinine (sCr) only to assess the severity of AKI. Complete AKI recovery was defined as the lowest post-AKI sCr within 20% of pre-AKI sCr values and partial recovery if within 30%, all within 90 days after TJA.

RESULTS

Twenty-four percent of the 1,212 subjects undergoing TJA had pre-existing CKD. The overall incidence of AKI in the CKD subjects was 30%; of these, 55% had stage-1 AKI, 1% had stage-2 AKI and 44% had stage-3 AKI. AKI was more common in African Americans, those with diabetes or heart failure, requiring perioperative transfusions or receiving diuretics before surgery. While 82% of the AKI subjects achieved complete recovery of kidney function, 4% had only partial recovery and 14% did not reach a post-AKI sCr level within 30% of pre-AKI values. The incidence (P < 0.001) but not the severity (P = 0.202) of AKI correlated with stages of baseline CKD.

CONCLUSIONS

The presence of CKD was associated with a high incidence of AKI after TJA. In these subjects, more than half the cases of AKI were of mild degree and had a favorable outcome. However, 18% of them did not have complete recovery of kidney function. Stages of baseline CKD were associated with increased incidence but not severity of AKI after TJA.

Protective role of skeletal muscle mass against progression from metabolically healthy to unhealthy phenotype

OBJECTIVE

Metabolically healthy individuals are known to be resistant to cardiovascular disease development. However, a considerable fraction of those individuals shows deteriorated metabolic health over time. Although skeletal muscle is the primary insulin-responsive target organ, a longitudinal investigation of the skeletal muscle mass in relation to the development of metabolically unhealthy phenotype has not been performed. We aimed to evaluate whether greater skeletal muscle mass is an independent protective factor for the development of metabolically unhealthy phenotype.

DESIGN, PARTICIPANTS AND MEASUREMENTS

We conducted a retrospective cohort study with 9033 metabolically healthy volunteers who underwent routine health examinations in 2012 and a follow-up examination in 2016. Obesity was defined as Asian-Pacific body mass index criterion ≥25 kg/m² . Subjects with fewer than two risk factors (elevated blood pressure, triglyceride, glucose, high-sensitivity C-reactive protein, insulin resistance and decreased high-density lipoprotein cholesterol levels) were characterized as metabolically healthy using Wildman criteria.

RESULTS

At the 4-year follow-up, approximately one-fourth of the nonobese participants and half of the participants with obesity showed metabolic deterioration. In nonobese men and women, higher appendicular skeletal muscle mass (ASM)/weight at baseline was significantly associated with decreased risk of metabolic deterioration. Compared to the lowest quartile of ASM/weight, the adjusted odds ratios (95% confidence intervals) of the highest quartile were 0.68 (0.52-0.89) in nonobese men and 0.64 (0.46-0.90) in nonobese women. However, this association was not observed in obese subjects.

CONCLUSIONS

Greater skeletal muscle mass at baseline is significantly associated with maintenance of metabolically healthy status, especially in nonobese individuals.

Maintenance of negative fluid balance can improve endothelial and cardiac functions in primary hypertensive patients

PURPOSE

The issue of unidentified volume expansion is well recognized as a cause for resistance to antihypertensive therapy. The aim of study is to identify contribution of negative fluid balance to hypertension control and impact on endothelial and cardiac functions among primary hypertensive patients who do not have kidney failure.

MATERIALS AND METHODS

This is a prospective interventional study with one-year follow-up. Preceded by volume status measurements were performed by a body composition monitor (BCM), the patients were put on ambulatory blood pressure monitoring for 24 hours. Then, echocardiographic assessments and flow-mediated dilation (FMD) and carotid intima-media thickness (CIMT) measurements were completed. Patients in one of the two groups were kept negative hydrated during trial with diuretic treatment.

RESULTS

At the end of one-year follow-up, patients in negative hydrated group were found to have significantly lower CIMT, left ventricle mass index, left ventricular end-diastolic diameter, mean systolic and diastolic BP, non-dipper patient ratio, and higher FMD. In negatively hydrated group, target organ damage significantly reduced during trial.

CONCLUSIONS

The significance of negative hydration status with respect to blood pressure control, endothelial and cardiac functions within primary hypertensive patients who do not suffer from kidney failure has been demonstrated.

Outcomes of diuretic use in pre-dialysis CKD patients with moderate renal deterioration attending tertiary care referral center

INTRODUCTION

Diuretic therapy has been the mainstay of treatment in chronic kidney disease (CKD) patients, primarily for hypertension and fluid overload. Apart from their beneficial effects, diuretic use is associated with adverse renal outcomes. The current study is aimed to determine the outcomes of diuretic therapy.

METHODOLOGY

A prospective observational study was conducted by inviting pre-dialysis CKD patients. Fluid overload was assessed by Bioimpedance analysis (BIA).

RESULTS

A total 312 patients (mean age 64.5 ± 6.43) were enrolled. Among 144 (46.1%) diuretic users, furosemide and hydrochlorothiazide (HCTZ) were prescribed in 69 (48%) and 39 (27%) patients, respectively, while 36 (25%) were prescribed with combination therapy (furosemide plus HCTZ). Changes in BP, fluid compartments, eGFR decline and progression to RRT were assessed over a follow-up period of 1 year. Maximum BP control was observed with combination therapy (-19.3 mmHg, p < 0.001) followed by furosemide [-10.6 mmHg with 80 mg thrice daily (p < 0.001)], -9.3 mmHg with 40-60 mg (p < 0.001) and -5.9 mmHg with 20-40 mg (p = 0.02) while HCTZ offered minimal SBP control [-3.7 mmHg with 12.5-25 mg (p = 0.04)]. Decline in extracellular water (ECW) ranged from -1.5 L(p = 0.01) with thiazide diuretics to -3.8 L(p < 0.001) with combination diuretics. Decline in eGFR was maximum (-3.4 ml/min/1.73 m², p = 0.01) with combination diuretics and least with thiazide diuretics (-1.6 ml/min/1.73 m², p = 0.04). Progression to RRT was observed in 36 patients.

CONCLUSION

It is cautiously suggested to discourage the use of diuretic combination therapy and high doses of single diuretic therapy. Prescribing of diuretics should be done by keeping in view benefit versus harm for each patient.

Clinical aspects of changes in water and sodium homeostasis in the elderly

The population of elderly individuals is increasing worldwide. With aging, various hormonal and kidney changes occur, both affecting water homeostasis. Aging is a risk factor for chronic kidney disease (CKD) and many features of CKD are reproduced in the aging kidney. Dehydration and hyperosmolarity can be triggered by diminished thirst perception in this population. Elderly with dementia are especially susceptible to abnormalities of their electrolyte and body water homeostasis and should be (re-)assessed for polypharmacy. Hypo- and hypernatremia can be life threatening and should be diagnosed and treated promptly, following current practice guidelines. In severe cases of acute symptomatic hyponatremia, a rapid bolus of 100 to 150 ml of intravenous 3% hypertonic saline is appropriate to avert catastrophic outcomes; for asymptomatic hyponatremia, a very gradual correction is preferred. In summary, the body sodium (Na+) balance is regulated by a complex interplay of environmental and individual factors. In this review, we attempt to provide an overview on this topic, including dehydration, hyponatremia, hypernatremia, age-related kidney changes, water and sodium balance, and age-related changes in the vasopressin and renin-angiotensin-aldosterone system.