The midnight-to-morning urinary cortisol increment method is not reliable for the assessment of hypothalamic-pituitary-adrenal insufficiency in patients with end-stage kidney disease

Hair cortisol and changes in cortisol dynamics in chronic kidney disease

Objective

We compared hair cortisol (HC) with classic tests of the hypothalamic-pituitary-adrenal (HPA) axis in chronic kidney disease (CKD) and assessed its association with kidney and cardiometabolic status.

Design and methods

A cross-sectional study of 48 patients with CKD stages I-IV, matched by age, sex, and BMI with 24 healthy controls (CTR) was performed. Metabolic comorbidities, body composition, and HPA axis function were studied.

Results

A total of 72 subjects (age 52.9 ± 12.2 years, 50% women, BMI 26.2 ± 4.1 kg/m2) were included. Metabolic syndrome features (hypertension, dyslipidaemia, glucose, HOMA-IR, triglycerides, waist circumference) and 24-h urinary proteins increased progressively with worsening kidney function (p < 0.05 for all). Reduced cortisol suppression after 1-mg dexamethasone suppression (DST) (p < 0.001), a higher noon (12:00 h pm) salivary cortisol (p = 0.042), and salivary cortisol AUC (p = 0.008) were seen in CKD. 24-h urinary-free cortisol (24-h UFC) decreased in CKD stages III-IV compared with I-II (p < 0.001); higher midnight salivary cortisol (p = 0.015) and lower suppressibility after 1-mg DST were observed with declining kidney function (p < 0.001). Cortisol-after-DST cortisol was >2 mcg/dL in 23% of CKD patients (12.5% in stage III and 56.3% in stage IV); 45% of them had cortisol >2 mcg/dL after low-dose 2-day DST, all in stage IV (p < 0.001 for all). Cortisol-after-DST was lineally inversely correlated with eGFR (p < 0.001). Cortisol-after-DST (OR 14.9, 95% CI 1.7-103, p = 0.015) and glucose (OR 1.3, 95% CI 1.1-1.5, p = 0.003) were independently associated with eGFR <30 mL/min/m2). HC was independently correlated with visceral adipose tissue (VAT) (p = 0.016). Cortisol-after-DST (p = 0.032) and VAT (p < 0.001) were independently correlated with BMI.

Conclusion

Cortisol-after-DST and salivary cortisol rhythm present progressive alterations in CKD patients. Changes in cortisol excretion and HPA dynamics in CKD are not accompanied by significant changes in long-term exposure to cortisol evaluated by HC. The clinical significance and pathophysiological mechanisms explaining the associations between HPA parameters, body composition, and kidney damage warrant further study.

Overnight 1-mg DST Serum Cortisol in Various Stages of Chronic Kidney Disease-Normative Data and Underlying Mechanisms

Context

Data on the overnight 1 mg-dexamethasone suppression test (ONDST) in renal dysfunction are limited.

Objective

We aim to determine the normative range of ONDST cortisol across chronic kidney disease (CKD) stages and reasons for its alteration.

Methods

Prospectively, 180 CKD (30 each in G2-G5/5D) patients and 30 healthy controls underwent ONDST 8 Am serum cortisol (chemiluminescent immunoassay [CLIA]). In an exploratory cohort, 45 (15 each: G3b/G4, G5/G5D, and healthy controls) individuals' blood biochemistry for basal (8 Am) cortisol and adrenocorticotropin (ACTH), post-ONDST 8 Am dexamethasone, ACTH, cortisol (CLIA and liquid chromatography-tandem mass spectrometry), and 4 Pm cortisol was collected.

Results

Post-ONDST cortisol (µg/dL) correlated inversely (r = 0.47; P < .005) with estimated glomerular filtration rate (eGFR) (mL/min/1.73 m2), with 95th percentile being 1.2 in controls, 3.0 in G2, 3.2 in G3a, 4.3 in G3b, 4.7 in G4, 5.7 in G5, and 7.1 in G5D. In the exploratory cohort, basal 8 Am cortisol and ACTH, and post-ONDST dexamethasone were similar among controls and CKD subgroups. ONDST ACTH (for evaluating the hypothalamo-pituitary-adrenal axis) was slightly higher in G5/5D vs controls (8.9 vs 6.1 pg/mL), while it was similar in G3b/G4 vs controls. Median 8 Am ONDST cortisol was similar on CLIA and LC-MS/MS in controls and higher on CLIA in G3b/4 (1.7 vs 1.1 µg/dL; P = .012) and G5/5D (2.4 vs 1.7 µg/dL; P = .002) than LC-MS/MS. Post-ONDST serum cortisol drop from 8 Am to 4 Pm was significant in controls (0.5-<0.2 µg/dL) and G3b/4 (1.7-1.2 µg/dL), but not in G5/5D (2.4-2.2 µg/dL).

Conclusion

The normative data of ONDST serum cortisol with eGFR-based cutoffs are useful in evaluating Cushing syndrome in CKD. Prolonged cortisol half-life and immunoassay-related assay cross-reaction are likely contributors to higher ONDST cortisol.

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.

Adrenal function testing in dialysis patients - a review of the literature

Background

Secondary adrenal insufficiency is a frequent issue in patients with renal replacement therapy. There are concerns about metabolism and clearance for adrenocorticotropic hormone (ACTH) and cortisol in addition to hemoconcentration as confounding factors during hemodialysis (HD). Therefore, ACTH testing is currently performed before or in between HD sessions. This review of the literature aims to evaluate the current evidence for validity of testing for adrenal insufficiency in patients on chronic renal replacement therapy.

Methods

A literature search of PubMed database for interventional and observational clinical trials was performed. Case reports and reviews were excluded. The search included all articles published until July 2020.

Results

Of 218 potentially eligible articles, 16 studies involving 381 participants were included. Seven studies performed an ACTH test before HD or in between HD sessions. There was no data available regarding ACTH testing during HD. But there was evidence of decreased cortisol levels during HD as compared to afterwards. All included 16 studies measured basal cortisol, and seven studies performed an ACTH test. Seven trials had comparable data of baseline cortisol for a quantitative analysis. Standardized mean difference of overall cortisol was 0.18 nmol/l (95%CI − 0.08 to 0.44) in the case group.

Conclusions

In patients undergoing renal replacement therapy, basal serum cortisol values are comparable to healthy volunteers. There is limited data on the validity of stimulated cortisol in these patients, especially during HD.

Trial registration

Registration no. CRD42020199245.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02541-5.

Prolactin and Other Pituitary Disorders in Kidney Disease

Prolactin levels are increased in chronic kidney disease (CKD) as a result of reduced clearance and increased secretion. Hyperprolactinemia manifests as galactorrhea and hypogonadism. Treatment of hyperprolactinemia should focus on improving bothersome galactorrhea or hypogonadism by using dopamine agonists and/or replacement of sex hormone(s). Changes in the hypothalamic-pituitary-adrenal axis in CKD are characterized by increases in adrenocorticotropic hormone (ACTH) and cortisol levels, largely preserved circadian rhythms of ACTH and cortisol, and a normal response of cortisol to ACTH, metyrapone, and insulin-induced hypoglycemia. However, the hypothalamic-pituitary-adrenal axis is less inhibited by 1 mg dexamethasone but retains normal suppression by higher-dose dexamethasone. Diagnosis of adrenal insufficiency in CKD patients, as in normal subjects, usually is made by finding a subnormal cortisol response to ACTH. The mainstay of treatment of adrenal insufficiency is to replace glucocorticoid hormone. Cushing's disease in CKD is difficult to diagnose and relies on the dexamethasone suppression test and the midnight salivary cortisol test because the 24-hour urine free cortisol test is not useful because it is increased already in CKD. Treatment of Cushing's disease involves surgery, complemented by radiation and/or medical therapy if necessary. Growth hormone levels are increased and insulin-like growth factor 1 levels are normal in patients with CKD. In a normal patient with CKD, as in one with acromegaly, there can be a paradoxic increase in growth hormone after an oral glucose load. Therefore, diagnosis of acromegaly in renal insufficiency is challenging. The treatment of choice for acromegaly is surgery, although data for medical treatment for acromegaly in CKD are rare. In patients with renal impairment, arginine vasopressin levels are increased as a result of decreased clearance, and there also is impairment of arginine vasopressin signaling in renal tubules. Diabetes insipidus can be masked in advanced kidney disease until kidney transplantation. Diagnosis of the syndrome of inappropriate antidiuretic hormone is similar in mild or moderate kidney disease as in normal subjects, but is challenging in patients with advanced kidney disease owing to the impairment in urine dilution.

Glucocorticoid activation by 11β-hydroxysteroid dehydrogenase enzymes in relation to inflammation and glycaemic control in chronic kidney disease: A cross-sectional study

OBJECTIVE

Patients with chronic kidney disease (CKD) have dysregulated cortisol metabolism secondary to changes in 11β-hydroxysteroid dehydrogenase (11β-HSD) enzymes. The determinants of this and its clinical implications are poorly defined.

METHODS

We performed a cross-sectional study to characterize shifts in cortisol metabolism in relation to renal function, inflammation and glycaemic control. Systemic activation of cortisol by 11β-HSD was measured as the metabolite ratio (tetrahydrocortisol [THF]+5α-tetrahydrocortisol [5αTHF])/tetrahydrocortisone (THE) in urine.

RESULTS

The cohort included 342 participants with a median age of 63 years, median estimated glomerular filtration rate (eGFR) of 28 mL/min/1.73 m2 and median urine albumin-creatinine ratio of 35.5 mg/mmol. (THF+5αTHF)/THE correlated negatively with eGFR (Spearman's ρ = -0.116, P = 0.032) and positively with C-reactive protein (ρ = 0.208, P < 0.001). In multivariable analysis, C-reactive protein remained a significant independent predictor of (THF+5αTHF)/THE, but eGFR did not. Elevated (THF+5αTHF)/THE was associated with HbA1c (ρ = 0.144, P = 0.008) and diabetes mellitus (odds ratio for high vs low tertile of (THF+5αTHF)/THE 2.57, 95% confidence interval 1.47-4.47). Associations with diabetes mellitus and with HbA1c among the diabetic subgroup were independent of eGFR, C-reactive protein, age, sex and ethnicity.

CONCLUSIONS

In summary, glucocorticoid activation by 11β-HSD in our cohort comprising a spectrum of renal function was associated with inflammation and impaired glucose control.

The diagnosis of Cushing's syndrome: an Endocrine Society Clinical Practice Guideline

OBJECTIVE

The objective of the study was to develop clinical practice guidelines for the diagnosis of Cushing's syndrome.

PARTICIPANTS

The Task Force included a chair, selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society, five additional experts, a methodologist, and a medical writer. The Task Force received no corporate funding or remuneration.

CONSENSUS PROCESS

Consensus was guided by systematic reviews of evidence and discussions. The guidelines were reviewed and approved sequentially by The Endocrine Society's CGS and Clinical Affairs Core Committee, members responding to a web posting, and The Endocrine Society Council. At each stage the Task Force incorporated needed changes in response to written comments.

CONCLUSIONS

After excluding exogenous glucocorticoid use, we recommend testing for Cushing's syndrome in patients with multiple and progressive features compatible with the syndrome, particularly those with a high discriminatory value, and patients with adrenal incidentaloma. We recommend initial use of one test with high diagnostic accuracy (urine cortisol, late night salivary cortisol, 1 mg overnight or 2 mg 48-h dexamethasone suppression test). We recommend that patients with an abnormal result see an endocrinologist and undergo a second test, either one of the above or, in some cases, a serum midnight cortisol or dexamethasone-CRH test. Patients with concordant abnormal results should undergo testing for the cause of Cushing's syndrome. Patients with concordant normal results should not undergo further evaluation. We recommend additional testing in patients with discordant results, normal responses suspected of cyclic hypercortisolism, or initially normal responses who accumulate additional features over time.