Hypertension in dialysis and kidney transplant patients

Treatment of Hypertension Because of Immunosuppressive Therapy After Solid Organ Transplantation-Pharmacological Approach

ABSTRACT

Solid organs transplantation procedures have been performed for more than half a century. Growing knowledge of immune response and development of new immunosuppressive regimens guarantee more and more successful outcomes. However, many of the applied drugs lead to cardiovascular complications, the most frequent of which is hypertension. This article describes epidemiology, pathogenetic mechanisms, and treatment of hypertension induced by immunosuppressive medication. The main impact is focused on drugs belonging to the following groups: calcineurin inhibitors, the inhibitors of the mammalian target of rapamycin, and glucocorticosteroids. We analyze the mechanism of action of the main hypertensive drugs and their influence on the reversing hypertonic action of the immunosuppressive agents. In the absence of current guidelines addressing this problem, this article is an attempt to fill the gap, helping clinicians to choose proper medication.

The Relation between Preserved Social Support, Resilience (Depression and Anxiety) and Psychiatric Disorders among a Sample of Egyptian Patients on Regular Hemodialysis

Background:

Patients on hemodialysis are at a high risk of psychiatric disorders as they face an emotional challenge in addition to physical impairment.

Objective:

This study aims to assess the prevalence of depression and anxiety among a sample of patients with end-stage renal disease on regular dialysis, and the effect of resilience and social support on them.

Methods:

This cross-sectional study was conducted on 45 patients who had been on hemodialysis for the past three months. Anxiety and depression were assessed with a clinical interview. The severity of depression, perceived social support, and resilience were assessed using the Beck Depression Inventory (BDI), Multi-dimensional Scale of Perceived Social Support (MSPSS), and Resilience Scale, respectively.

Result:

The mean age of enrolled patients was 49.2 ± 14.0 years, and the mean duration of hemodialysis was 4.5 ± 3.8 years. The prevalence of depression was 24.4% and that of anxiety was 20%. According to our analysis, 15 (33.3%) patients were diagnosed with minor depression, 6 (13.3%) with mild depression, 14 (31.1%) with moderate depression, and 10 (22.2%) with severe depression. Resilience correlated significantly with a psychiatric diagnosis (p=0.004). Perceived social support was also found to be significantly correlated with a psychiatric diagnosis (p=0.012).

Conclusion:

Depression and anxiety are common mental disorders in patients with CKD and are considered as the main determinants of quality of life and death rate. Increasing awareness, early evaluation, and management of depression and anxiety may improve the functional, social, and clinical outcomes of the patients with CKD.

Meta-analysis of cognitive functioning in patients following kidney transplantation

Background

There is mixed evidence regarding the nature of cognitive function in patients who have undergone renal transplantation. The aim of this meta-analysis was to examine which cognitive domains are impacted following kidney transplantation and how performance compares with non-transplanted patients or healthy controls/normative data.

Method

A systematic search was conducted using keywords within three databases (Embase, MEDLINE and PsychINFO), yielding 458 unique studies, 10 of which met the inclusion criteria. Neuropsychological tests were grouped into nine cognitive domains and three separate analyses were undertaken within each domain: (i) within subjects pre- versus post-transplant, (ii) transplanted versus non-transplanted patients and (iii) transplanted versus healthy matched controls and standardized normative data.

Results

Transplanted patients showed moderate to large improvements in the domains of general cognitive status (g = 0.526), information and motor speed (g = 0.558), spatial reasoning (g = 0.376), verbal memory (g = 0.759) and visual memory (g = 0.690) when compared with their pre-operative scores. Test scores in the same five domains were significantly better in post-transplanted patients when compared with dialysis-dependant or conservatively managed chronic kidney disease patients. However, post-transplanted patients’ performance was significantly low compared with that of healthy controls (and standardized normative data) in the domains of executive functioning (g = −0.283), verbal fluency (g = −0.657) and language (g = −0.573).

Conclusions

Two key issues arise from this review. First, domain-specific cognitive improvement occurs in patients after successful transplantation. Nevertheless, transplanted patients still performed significantly below healthy controls in some domains. Second, there are important shortcomings in existing studies; the length of follow-up is typically short and only limited neuropsychological test batteries are employed. These factors are important in order to support the recovery of cognitive function among patients following renal transplant.

Hypertension after Kidney Transplantation: Clinical Significance and Therapeutical Aspects

Most of the kidney transplanted patients develop arterial hypertension after renal transplantation. Together with very well-known and usual risk factors, post-transplant hypertension contributes to the whole cardiovascular morbidity and mortality in the kidney transplant population. The reasons of post-transplant hypertension are factors related to donors and recipients, immunosuppressive therapy like Calcineurin Inhibitors (CNI) and surgery procedures (stenosis and kinking of the renal artery and ureteral obstruction). According to Eighth National Committee (JNC 8) recommendations, blood pressure > 140/90 mmHg is considered as hypertension. The usual antihypertensive drugs used for the control of hypertension are Calcium channel blockers (CCB), Angiotensin-converting enzyme (ACE) inhibitors, Angiotensin -II receptor blockers (ARB), B- blockers and diuretics. Follow the KDIGO guidelines the target blood pressure < 140/90 mmHg for patients without proteinuria and < 125/75 mmHg in patients with proteinuria is recommended. Better control of post-transplant hypertension improves the long-term graft and patient's survival.

Molecular remodeling of the renin-angiotensin system after kidney transplantation

Objective:

We aimed at assessing the molecular adaptation of the renin-angiotensin system (RAS) after successful kidney transplantation (KTX).

Materials and methods:

In this prospective, exploratory study we analyzed 12 hemodialysis (HD) patients, who received a KTX and had excellent graft function six to 12 months thereafter. The concentrations of plasma Angiotensin (Ang) peptides (Ang I, Ang II, Ang-(1–7), Ang-(1–5), Ang-(2–8), Ang-(3–8)) were simultaneously quantified with a novel mass spectrometry-based method. Further, renin and aldosterone concentrations were determined by standard immunoassays.

Results:

Ang values showed a strong inter-individual variability among HD patients. Yet, despite a continued broad dispersion of Ang values after KTX, a substantial improvement of the renin/Ang II correlation was observed in patients without RAS blockade or on angiotensin receptor blocker (HD: renin/Ang II R² = 0.660, KTX: renin/Ang II R² = 0.918). Ang-(1–7) representing the alternative RAS axis was only marginally detectable both on HD and after KTX.

Conclusions:

Following KTX, renin-dependent Ang II formation adapts in non-ACE inhibitor-treated patients. Thus, a largely normal RAS regulation is reconstituted after successful KTX. However, individual Ang concentration variations and a lack of potentially beneficial alternative peptides after KTX call for individualized treatment. The long-term post-transplant RAS regulation remains to be determined.

Renin-angiotensin-aldosterone (RAAS): The ubiquitous system for homeostasis and pathologies

Renin-angiotensin-aldosterone system (RAAS) is a vital system of human body, as it maintains plasma sodium concentration, arterial blood pressure and extracellular volume. Kidney-secreted renin enzyme acts on its substrate to form angiotensin II, a versatile effector peptide hormone. Every organ is affected by RAAS activation and the resultant hypertension, cell proliferation, inflammation, and fibrosis. The imbalance of renin and angiotensin II can result in an overwhelming number of chronic and acute diseases. RAAS is influenced by other enzymes, hormones, pumps and signaling pathways, hence, this review discusses important facets of this system, its crosstalk with other crucial factors like estrogen, thyroid, cortisol, kallikrein-kinin system, Wnt/β-catenin signaling, and sodium-potassium pump. The nexus of RAAS with the above-discussed systems was scantily explored before. So, this review furnishes a new perspective in comprehension of inflammation diseases. It is followed by the formulation of hypotheses, which can contribute to better management of an array of pathologies plaguing mankind. Manipulation of RAAS, by bending it towards ACE2 expression can regulate endocrine functions, which can be critical for a number of pathological management. Dietary intervention can restore RAAS to normalcy.

Relationship between different blood pressure measurements and left ventricular mass by cardiac magnetic resonance imaging in end-stage renal disease

Hypertension is prevalent in patients with end-stage renal disease and is strongly associated with left ventricular hypertrophy (LVH), an independent predictor of cardiovascular mortality. Blood pressure (BP) monitoring in hemodialysis patients may be unreliable because of its lability and variability. We compared different methods of BP measurement and their relationship with LVH on cardiac magnetic resonance imaging. Sixty patients undergoing chronic hemodialysis at a single dialysis center had BP recorded at each dialysis session over 12 weeks: pre-dialysis, initial dialysis, nadir during dialysis, and post-dialysis. Forty-five of these patients also underwent 44-hour inter-dialytic ambulatory BP monitoring. Left ventricular mass index (LVMI) was measured using cardiac magnetic resonance imaging and the presence of LVH was ascertained. Receiver operator characteristic curves were generated for each BP measurement for predicting LVH. The mean LVMI was 68 g/m(2) (SD = 15 g/m(2)); 13/60 patients (22%) had LVH. Mean arterial pressure measured shortly after initiation of dialysis session was most strongly correlated with LVMI (Pearson correlation coefficient r = 0.59, P < .0001). LVH was best predicted by post-dialysis systolic BP (area under the curve, 0.83; 95% confidence interval, 0.72-0.94) and initial dialysis systolic BP (area under the curve, 0.81; 95% confidence interval, 0.70-0.92). Forty-four-hour ambulatory BP and BP variability did not significantly predict LVH. Initial dialysis mean arterial pressure and systolic BP and post-dialysis systolic BP are the strongest predictors of LVH, and may represent the potentially best treatment targets in hemodialysis patients to prevent end-organ damage. Further studies are needed to confirm whether treatment targeting these BP measurements can optimize cardiovascular outcomes.