Effects of haemodialysis session on plasma beta-endorphin, ACTH and cortisol in patients with end-stage renal disease

Feasibility of remote self-collection of dried blood spots, hair, and nails among people with HIV with hazardous alcohol use

BACKGROUND

The use of biomarkers in behavioral HIV research can help to address limitations of self-reported data. The COVID-19 pandemic forced many researchers to transition from standard in-person data collection to remote data collection. We present data on the feasibility of remote self-collection of dried blood spots (DBS), hair, and nails for the objective assessment of alcohol use, antiretroviral therapy adherence, and stress in a sample of people with HIV (PWH) who are hazardous drinkers.

METHODS

Standardized operating procedures for remote self-collection of DBS, hair, and nails were developed for an ongoing pilot study of a transdiagnostic alcohol intervention for PWH. Prior to each study appointment, participants were mailed a kit containing materials for self-collection, instructions, a video link demonstrating the collection process, and a prepaid envelope for returning samples.

RESULTS

A total of 133 remote study visits were completed. For DBS and nail collection at baseline, 87.5% and 83.3% of samples, respectively, were received by the research laboratory, of which 100% of samples were processed. Although hair samples were intended to be analyzed, most of the samples (77.7%) were insufficient or the scalp end of the hair was not marked. We, therefore, decided that hair collection was not feasible in the framework of this study.

CONCLUSION

An increase in remote self-collection of biospecimens may significantly advance the field of HIV-related research, permitting the collection of specimens without resource-intensive laboratory personnel and facilities. Further research is needed on the factors that impeded participants' ability to complete remote biospecimen collection.

Association between adrenal function and dialysis vintage in hemodialysis patients

INTRODUCTION

Adrenal insufficiency in hemodialysis patients is commonly encountered in clinical practice. However, its association with end-stage renal disease is unclear. We investigated the relationship between adrenal function and relevant clinical parameters, focusing on dialysis vintage.

METHODS

Altogether, 100 maintenance hemodialysis patients were enrolled (age: 69.8 ± 11.8 years, dialysis vintage: 9.4 ± 9.2 years). Basal serum cortisol levels were measured and their associations with relevant clinical parameters were investigated. Subsequently, hormone stimulation tests were performed to assess adrenal function.

RESULTS

Basal serum cortisol significantly decreased with an increase in dialysis vintage (< 10 years, 11.9 ± 3.7 μg/dL; 10-19 years, 10.9 ± 2.9 μg/dL; ≥ 20 years, 9.7 ± 3.8 μg/dL). Basal cortisol was negatively correlated with dry weight, β2-microglobulin, creatinine, and lymphocyte count and positively correlated with brachial-ankle pulse wave velocity. Significant negative correlations were observed between basal cortisol and dialysis vintage after adjusting for confounding variables in the multivariate analysis. Standard adrenocorticotropic hormone (ACTH) and corticotropin-releasing hormone (CRH) stimulation tests were performed in 17 patients. Seven patients were diagnosed with adrenal insufficiency and all of them had a long dialysis vintage (≥ 10 years). According to the rapid ACTH test, cortisol responses were significantly decreased in patients with long dialysis vintage compared to those with short dialysis vintage (< 10 years). Similar findings were observed in ten patients without adrenal insufficiency. The CRH loading test showed similar tendencies, although the differences were not statistically significant.

CONCLUSIONS

Adrenal function decreased with an increase in dialysis vintage. Long-term dialysis patients might be susceptible to adrenal insufficiency.

Cortisol excess in chronic kidney disease - A review of changes and impact on mortality

Chronic kidney disease (CKD) describes the long-term condition of impaired kidney function from any cause. CKD is common and associated with a wide array of complications including higher mortality, cardiovascular disease, hypertension, insulin resistance, dyslipidemia, sarcopenia, osteoporosis, aberrant immune function, cognitive impairment, mood disturbances and poor sleep quality. Glucocorticoids are endogenous pleiotropic steroid hormones and their excess produces a pattern of morbidity that possesses considerable overlap with CKD. Circulating levels of cortisol, the major active glucocorticoid in humans, are determined by a complex interplay between several processes. The hypothalamic-pituitary-adrenal axis (HPA) regulates cortisol synthesis and release, 11β-hydroxysteroid dehydrogenase enzymes mediate metabolic interconversion between active and inactive forms, and clearance from the circulation depends on irreversible metabolic inactivation in the liver followed by urinary excretion. Chronic stress, inflammatory states and other aspects of CKD can disturb these processes, enhancing cortisol secretion via the HPA axis and inducing tissue-resident amplification of glucocorticoid signals. Progressive renal impairment can further impact on cortisol metabolism and urinary clearance of cortisol metabolites. Consequently, significant interest exists to precisely understand the dysregulation of cortisol in CKD and its significance for adverse clinical outcomes. In this review, we summarize the latest literature on alterations in endogenous glucocorticoid regulation in adults with CKD and evaluate the available evidence on cortisol as a mechanistic driver of excess mortality and morbidity. The emerging picture is one of subclinical hypercortisolism with blunted diurnal decline of cortisol levels, impaired negative feedback regulation and reduced cortisol clearance. An association between cortisol and adjusted all-cause mortality has been reported in observational studies for patients with end-stage renal failure, but further research is required to assess links between cortisol and clinical outcomes in CKD. We propose recommendations for future research, including therapeutic strategies that aim to reduce complications of CKD by correcting or reversing dysregulation of cortisol.

Effect of Hydrocortisone on Intradialytic Hypotension: A Preliminary Investigational Study

Introduction

Approximately 15 to 33% of all dialysis treatments are complicated by intradialytic hypotension (IDH). In this study, we tested the hypothesis that the intravenous administration of hydrocortisone prior to HD treatment could prevent IDH or at least decrease the drop in the blood pressure resulting from IDH.

Methods

This study was approved by our local ethics committee/IRB (2017/87) and by the Jordan Food and Drug Administration (7/clinical/18). Additionally, it is registered on ClinicalTrials.gov (NCT03465007). In this preliminary investigational study, we screened all chronic hemodialysis patients at our clinic who were 18 years of age or older (n = 82) for IDH. There were 14 patients included in the interventional part of this study; patients were given IV hydrocortisone for 3 consecutive HD sessions, followed or preceded by 3 intervention-free sessions where they were given 5 ml of saline as a placebo.

Results

The initial total sample size was 82 patients. The frequency of IDH at our clinic was 24.4%. Fourteen out of the 20 patients who were diagnosed with IDH agreed to enroll in the interventional part of our study. The mean age of the patients in the interventional part of our study was 53.5 years (±10.3). These patients included 5 (35.7%) men and 9 (64.3%) women. Upon comparing the number of hypotensive attacks with and without the hydrocortisone administration, we found a significant difference (p = 0.003) between the hydrocortisone and placebo treatments in which 12 (85.7%) patients had fewer IDH episodes with the hydrocortisone treatment than with placebo.

Conclusion

This preliminary investigational study found that the administration of a stress dose of hydrocortisone prior to hemodialysis could be an effective measure for preventing or minimizing the risk of IDH episodes. Additional prospective studies on this subject are needed. Ruling out adrenal insufficiency in patients diagnosed with IDH is also crucial.

DIAGNOSIS OF ENDOCRINE DISEASE: Differentiation of pathologic/neoplastic hypercortisolism (Cushing's syndrome) from physiologic/non-neoplastic hypercortisolism (formerly known as pseudo-Cushing's syndrome)

Endogenous hypercortisolism (Cushing's syndrome) usually implies the presence of a pathologic condition caused by either an ACTH-secreting neoplasm or autonomous cortisol secretion from a benign or malignant adrenal neoplasm. However, sustained or intermittent hypercortisolism may also accompany many medical disorders that stimulate physiologic/non-neoplastic activation of the HPA axis (formerly known as pseudo-Cushing's syndrome); these two entities may share indistinguishable clinical and biochemical features. A thorough history and physical examination is often the best (and sometimes only) way to exclude pathologic/neoplastic hypercortisolism. The presence of alcoholism, renal failure, poorly controlled diabetes and severe neuropsychiatric disorders should always raise suspicion that the presence of hypercortisolism may be related to physiologic/non-neoplastic Cushing's syndrome. As late-night salivary cortisol and low-dose dexamethasone suppression have good sensitivity and negative predictive value, normal studies exclude Cushing's syndrome of any form. However, these tests have imperfect specificity and additional testing over time with clinical follow-up is often needed. When there is persistent diagnostic uncertainty, secondary tests such as the DDAVP stimulation test and the dexamethasone-CRH test may provide evidence for the presence or absence of an ACTH-secreting tumor. This review will define and characterize the numerous causes of physiologic/non-neoplastic hypercortisolism and provide a rational clinical and biochemical approach to distinguish it from pathologic/neoplastic hypercortisolism (true Cushing's syndrome).

The relationship between renal function and plasma concentration of the cachectic factor zinc-alpha2-glycoprotein (ZAG) in adult patients with chronic kidney disease

Zinc-α2-glycoprotein (ZAG), a potent cachectic factor, is increased in patients undergoing maintenance dialysis. However, there is no data for patients before initiation of renal replacement therapy. The purpose of the present study was to assess the relationship between plasma ZAG concentration and renal function in patients with a large range of glomerular filtration rate (GFR). Plasma ZAG concentration and its relationship to GFR were investigated in 71 patients with a chronic kidney disease (CKD) stage 1 to 5, 17 chronic hemodialysis (HD), 8 peritoneal dialysis (PD) and 18 non-CKD patients. Plasma ZAG concentration was 2.3-fold higher in CKD stage 5 patients and 3-fold higher in HD and PD patients compared to non-CKD controls (P<0.01). The hemodialysis session further increased plasma ZAG concentration (+39%, P<0.01). An inverse relationship was found between ZAG levels and plasma protein (r_s = −0.284; P<0.01), albumin (r_s = −0.282, P<0.05), hemoglobin (r_s = −0.267, P<0.05) and HDL-cholesterol (r_s = −0.264, P<0.05) and a positive correlation were seen with plasma urea (r_s = 0.283; P<0.01). In multiple regression analyses, plasma urea and HDL-cholesterol were the only variables associated with plasma ZAG (r² = 0.406, P<0.001). In CKD-5 patients, plasma accumulation of ZAG was not correlated with protein energy wasting. Further prospective studies are however needed to better elucidate the potential role of ZAG in end-stage renal disease.

Circadian rhythm of salivary cortisol, plasma cortisol, and plasma ACTH in end-stage renal disease

OBJECTIVE

Patients with end-stage renal disease (ESRD) can display the features of endogenous hypercortisolism but are difficult to evaluate for Cushing's syndrome. We evaluated the circadian rhythm of plasma compared with salivary cortisol in subjects with ESRD.

DESIGN

Plasma and salivary cortisol and plasma ACTH samples were drawn frequently over 24 h in an inpatient research unit in stable ESRD subjects on daytime chronic hemodialysis (n=16) vs controls (n=8).

METHODS

Plasma cortisol was measured every 2 h from 0800 to 0600 h the following day. Salivary cortisol was measured every 2 h, except between 2400 and 0400 h (sleep time). Plasma ACTH measured in a subset of samples and C-reactive protein (CRP) was measured as a marker of a subclinical inflammatory state in all subjects.

RESULTS

ESRD subjects had a discernable circadian rhythm in plasma and salivary cortisol, but with a significantly higher nadir (1800-2400 h) compared with the controls (P=0.016-<0.001). After excluding four ESRD subjects without a normal circadian rhythm, the ESRD subjects still had higher nadir plasma and salivary cortisol and plasma ACTH compared with controls. There was no difference in the correlation of salivary and plasma cortisol in control vs ESRD subjects. ESRD subjects had higher CRP levels compared with controls.

CONCLUSIONS

ESRD subjects had increased late-night plasma and salivary cortisol and plasma ACTH levels. Late-night salivary cortisol is a reliable index of plasma cortisol in ESRD patients.

Sleep pattern in an experimental model of chronic kidney disease

The prevalence of sleep disorders is significantly elevated in chronic kidney disease (CKD) patients. Numerous factors likely contribute to the high prevalence of sleep problems in uremic patients. The objective of this study was to evaluate the long-term sleep pattern changes in uremic rats during disease progression. Sleep recordings of the rats were monitored during light and dark periods that lasted 12 h each. These recordings were performed on days 7, 30, 60, and 90 after CKD induction. Cardiovascular, hormonal, and biochemical changes were evaluated at these same time points in control and uremic rats. CKD progression was reflected by the presence of hypertension and progressive increases in urea, creatinine, and cholesterol levels. We also observed hormonal fluctuations of corticosterone and ACTH, which indicated a potential alteration in the hypothalamic-pituitary-adrenal axis in diseased rats. In addition, rats with CKD demonstrated fragmented sleep with a greater number of arousals and decreased sleep efficiency in the light period during disease progression. In the dark period, there was an initial increase in sleep efficiency in CKD rats, but after 90 days of CKD, these animals slept less compared with the control group. Collectively, these metabolic and cardiovascular changes were associated with the persistent alterations in sleep architecture observed in CKD rats.

Alpha-melanocyte stimulating hormone and adrenocorticotropic hormone: an alternative approach when thinking about restless legs syndrome?

Alpha-melanocyte stimulating hormone (alpha-MSH) and adrenocorticotropic hormone (ACTH) possess properties suggesting that they may be involved in the pathogenesis of restless legs syndrome (RLS). We sought to determine if alpha-MSH and ACTH when administered centrally in rat recapitulate features reminiscent of RLS: increased activity, sleep fragmentation, and periodic movements during sleep. Rats were instrumented with electroencephalography, electromyography, and intracerebral cannulae and recorded for the measurement of sleep, periodic movements, and behavior following intracerebroventricular administration of alpha-MSH, ACTH, or saline. Studied behavior included grooming, locomotion, and rearing during wake and limb movements during sleep. Vigilance states included active wake (AW), quiet wake (QW), slow wave sleep I (SWSI), slow wave sleep II (SWSII), and paradoxical sleep (PS). All rats received normal saline acting as their own controls. Different rats received alpha-MSH in doses of 0.05, 0.5, 1.0, 2.0, and 6.0 microg or ACTH in doses of 0.5, 1.0, and 2.0 microg. Administered alpha-MSH caused an increase in waking behavior and prolongation of sleep latency, while ACTH stimulated waking behavior and fragmented sleep, yielding more AW and less SWSII and PS. Both hormones increased periodic movements during sleep. When administered centrally in rat, alpha-MSH and ACTH stimulate motor activity in wake, cause changes in sleep architecture, and increase periodic movements in sleep. These melanocortin hormones may play a role in the pathogenesis of RLS.

Late-night salivary cortisol measurement in the diagnosis of Cushing's syndrome

Making a definite diagnosis of Cushing's syndrome is a challenging problem. Unsuspected Cushing's syndrome occurs in 2-3% of patients with poorly controlled diabetes, 0.5-1% with hypertension, 6-9% with incidental adrenal masses, and 11% with unexplained osteoporosis and vertebral fractures. The increasing recognition of this syndrome highlights the need for a simple, sensitive, and specific diagnostic test. Patients with Cushing's syndrome consistently do not reach a normal nadir of cortisol secretion at night. The measurement of late-night salivary cortisol levels might, therefore, provide a new diagnostic approach for this disorder. Salivary cortisol concentrations reflect those of active free cortisol in plasma and saliva samples can easily be obtained in a nonstressful environment (e.g. at home). Late-night salivary cortisol measurement yields excellent overall diagnostic accuracy for Cushing's syndrome, with a sensitivity of 92-100% and a specificity of 93-100%. Several factors can, however, make interpretation of results difficult; these factors include disturbed sleep-wake cycles, contamination of samples (particularly by topical corticosteroids), and illnesses known to cause physiologic activation of the pituitary-adrenal axis. In this Review, we discuss the methods and value of measuring salivary cortisol for the diagnosis of Cushing's syndrome, and put forward some recommendations to maximize accuracy of results.

Inconsistency of reported uremic toxin concentrations

Discrepancies in reported uremic toxin concentrations were evaluated for 78 retention solutes. For this analysis, 378 publications were screened. Up to eight publications per toxin were retained. The highest and the lowest reported concentrations, as well as the median reported concentration were registered. The ratio between the highest and the lowest (H/L) concentrations and, for some solutes, also the ratio between the highest and the median (H/M) concentrations were calculated. The compounds were arbitrarily subdivided into three groups based on their H/L ratio: group A, H/L < 3 (n = 33); group B, 3 < H/L < 8.5 (n = 20); and group C, H/L > 8.5 (n = 25). Solutes of groups A and B showed a low to intermediate scatter, suggesting a homogeneity of reported data. Group C showed a more substantial scatter. For at least 10 compounds of group C, extremely divergent concentrations were registered (H/M > 5.5) using scatter plot analysis. For all solutes of groups A and B, the highest reported concentration could be used as a reference. For some solutes of group C and for the compounds showing a divergent scatter analysis, however, more refined directives should be followed.