Defining adrenal status with salivary cortisol by gold-standard insulin hypoglycemia

Expanding the use of salivary cortisol as a non-invasive outpatient test in the dynamic evaluation of suspected adrenal insufficiency

Background

Adrenal insufficiency (AI) is potentially life-threatening, and accurate diagnosis is crucial. The first-line diagnostic test, the adrenocorticotrophic hormone (ACTH) stimulation test, measures serum total cortisol. However, this is affected in states of altered albumin or cortisol-binding globulin levels, limiting reliability. Salivary cortisol reflects free bioactive cortisol levels and is a promising alternative. However, few studies are available, and heterogenous methodologies limit applicability.

Methods

This study prospectively recruited 42 outpatients undergoing evaluation for AI, excluding participants with altered cortisol-binding states. Serum (immunoassay) and salivary (liquid chromatography tandem mass spectrometry) cortisol levels were sampled at baseline, 30 min, and 60 min following 250 µg synacthen administration. AI was defined as a peak serum cortisol level <500 nmol/L in accordance with guidelines.

Results

The study recruited 21 (50%) participants with AI and 21 without AI. There were no significant differences in baseline characteristics, blood pressure, or sodium levels between groups. Following synacthen stimulation, serum and salivary cortisol levels showed good correlation at all timepoints (R2 = 0.74, P < 0.001), at peak levels (R2 = 0.72, P < 0.001), and at 60 min (R2 = 0.72, P < 0.001). A salivary cortisol cut-off of 16.0 nmol/L had a sensitivity of 90.5% and a specificity of 76.2% for the diagnosis of AI.

Conclusion

This study demonstrates a good correlation between serum and salivary cortisol levels during the 250 µg synacthen test. A peak salivary cortisol cut-off of 16.0 nmol/L can be used for the diagnosis of AI. It is a less invasive alternative to evaluate patients with suspected AI. Its potential utility in the diagnosis of AI in patients with altered cortisol-binding states should be further studied.

Prevalence of growth hormone deficiency in patients with unexplained chronic fatigue after undergoing bone marrow transplantation in adulthood

PURPOSE

Many patients who undergo bone marrow transplantation (BMT) in adulthood experience unexplained chronic fatigue which can have a major impact on their health-related quality of life (QoL). Pre-BMT treatment regimens increase the risk of developing acquired growth hormone deficiency (GHD), which results in a clinical syndrome with decreased energy and has additionally been linked to metabolic syndrome.

METHODS

Using the gold-standard insulin hypoglycemic test (IHT), we evaluated the prevalence of GHD in 18 post-BMT adult patients with unexplained chronic fatigue, as well as the correlation between peak serum GH response and QoL scores, the metabolic syndrome, and insulin resistance. Peak serum GH cut-point less than 3.0 ug/L was used for the diagnosis of severe GHD. The Fatigue Severity Scale and Quality of Life in Adult GHD Assessment questionnaires were used to quantify fatigue symptoms.

RESULTS

The prevalence of severe GHD within this sample of 18 patients was 50%. A trend between lower peak serum GH response and higher fatigue and QoL-AGHDA scores was observed.

CONCLUSIONS

GHD may represent a remediable contributor to post-BMT chronic fatigue in adults, further studies are needed to evaluate the potential role of screening and GH replacement therapy in this vulnerable patient population.

IMPLICATIONS FOR CANCER SURVIVORS

GHD may be a treatable explanation for disabling post-BMT fatigue pending results of intervention studies.

Stimulated Salivary Cortisol as a Noninvasive Diagnostic Tool for Adrenal Insufficiency

BACKGROUND

Salivary cortisol is routinely used as a diagnostic test for Cushing syndrome. The diagnostic use of salivary cortisol for adrenal insufficiency (AI), however, is less established. We aimed to investigate the utility of morning basal and adrenocorticotropic hormone-stimulated salivary cortisol in diagnosing AI in Korean adults.

METHODS

We prospectively included 120 subjects (female, n=70) from Seoul National University Hospital. AI was defined as a stimulated serum cortisol level of &lt;496.8 nmol/L during the short Synacthen test (SST). Serum and saliva samples were drawn between 8:00 AM and 10:00 AM. Salivary cortisol levels were measured using an enzyme immunoassay kit.

RESULTS

Thirty-four patients were diagnosed with AI according to the SST results. Age, sex, body mass index, serum albumin levels, and serum creatinine levels did not significantly differ between the normal and AI groups. Basal and stimulated salivary cortisol levels were positively correlated with basal (r=0.538) and stimulated serum cortisol levels (r=0.750), respectively (all P&lt;0.001). Receiver operating characteristic curve analysis yielded a cutoff level of morning basal salivary cortisol of 3.2 nmol/L (sensitivity, 84.9%; specificity, 73.5%; area under the curve [AUC]=0.822). The optimal cutoff value of stimulated salivary cortisol was 13.2 nmol/L (sensitivity, 90.7%; specificity, 94.1%; AUC=0.959). Subjects with a stimulated salivary cortisol level above 13.2 nmol/L but a stimulated serum cortisol level below 496.8 nmol/L (n=2) had lower serum albumin levels than those showing a concordant response.

CONCLUSION

The diagnostic performance of stimulated salivary cortisol measurements after the SST was comparable to serum cortisol measurements for diagnosing AI.

Salivary cortisol levels by tandem mass spectrometry during high dose ACTH stimulation test for adrenal insufficiency in children

PURPOSE

Serum cortisol measurements after ACTH stimulation are currently used to evaluate for adrenal insufficiency in children. We aim to determine if salivary cortisol measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) can confirm or replace serum cortisol during high dose ACTH stimulation test to improve test compliance and interpretation. We also aim to gain preliminary understanding of normal ranges of salivary cortisol in normal children at am, bedtime, and midnight.

METHODS

Children aged 6-17 years meeting study criteria and tested for adrenal insufficiency were recruited to concomitantly collect saliva and serum samples during high dose ACTH stimulation test. Normal children aged 3-18 years were recruited to collect morning, bedtime, and midnight saliva samples. Salivary cortisol was measured using LC-MS/MS while serum cortisol was determined by an immunoassay.

RESULTS

Salivary cortisol in normal children were higher at am and lower at bedtime and midnight (p value <0.0002 and <0.007, respectively). The midnight and bedtime levels were not sufficiently different (p value 0.36). Salivary cortisol during ACTH stimulation test positively and closely correlated with serum cortisol with 100% specificity and sensitivity when 18 µg/dL for serum and 500 ng/dL for salivary cortisol were used as cutoff values respectively for adrenal sufficiency.

CONCLUSIONS

Measurement of salivary cortisol by LC-MS/MS is less invasive, more convenient and better time controlled in busy pediatric clinic, therefore is better suited for young children to be used during high dose ACTH stimulation test to evaluate for adrenal insufficiency and to assist interpretation of test results by serum cortisol.

Prolonged hypothalamic-pituitary-adrenal axis activation after acute coronary syndrome in the GENESIS-PRAXY cohort

Background

Glucocorticoid excess has been linked with cardiovascular disease. Little is known about the long-term cortisol response in patients after acute coronary syndrome.

Design

The objective of this study was to describe the distribution of salivary cortisol in the post-acute phase of acute coronary syndrome and to describe the association of late-night salivary cortisol with cardiovascular risk factors.

Methods

We used late-night salivary cortisol measurements post-discharge to estimate hypothalamic-pituitary-adrenal axis activity in 309 patients aged 18–55 years enrolled in the GENESIS-PRAXY study from January 2009–April 2013. We evaluated hypothalamic-pituitary-adrenal axis activity and its association with hypertension, dyslipidemia, diabetes, smoking, family history, prior acute coronary syndrome, psychiatric diseases, acute coronary syndrome severity, as well as mortality and rate of rehospitalization at 12 months.

Results

Persistently elevated late-night salivary cortisol>2.92 nmol/l was seen in 99 (32.0%) patients: within the range of what may be seen in Cushing’s disease. Elevated late-night salivary cortisol was associated with previous acute coronary syndrome (13.3% vs 24.2%, p = 0.02), peripheral vascular disease (3.8% vs 13.1%, p = 0.002), and smoking (32.9% vs 46.5% p = 0.02). Elevated late-night salivary cortisol was associated with higher hemoglobin A1c values (5.6 ± 3.0 vs 6.1 ± 2.9, p = 0.008) and lower high density lipoprotein values (0.94 ± 0.53 vs 0.86 ± 0.50, p = 0.01). There were no differences in psychiatric symptom scores, acute coronary syndrome severity or mortality, and rate of rehospitalization at 12 months.

Conclusions

Many patients post-acute coronary syndrome have prolonged, marked activation of the hypothalamic-pituitary-adrenal axis. Late-night salivary cortisol co-associates with several cardiovascular risk factors. Further studies are needed to confirm the exact role of hypothalamic-pituitary-adrenal axis activity in the pathophysiology of cardiovascular disease.

Salivary Cortisol and Cortisone After Low-Dose Corticotropin Stimulation in the Diagnosis of Adrenal Insufficiency

Context:

Basal and poststimulation salivary cortisol and cortisone levels can be useful in the diagnosis of adrenal insufficiency. However, little is known about the optimal cutoffs and performance characteristics of these tests.

Objective:

To derive the cutoff values and study the performance characteristics of salivary cortisol and salivary cortisone in the diagnosis of adrenal insufficiency.

Design and Setting:

Prospective study in a regional hospital in Hong Kong from January 2014 to September 2015.

Participants:

Fifty-six Chinese healthy volunteers and 171 patients suspected of having adrenal insufficiency.

Main Outcome Measures:

All participants underwent low-dose short Synacthen test (LDSST) with intravenous injection of 1 μg of tetracosactide (Synacthen 1–24). Serum cortisol, salivary cortisol and cortisone levels were measured at baseline and 30 and 60 minutes afterward.

Results:

Using the reference cutoff (mean − 2 standard deviations of post-LDSST peak serum cortisol) derived from healthy volunteers as the gold standard, receiver operating characteristic analysis of patients’ data revealed that both post-LDSST peak salivary cortisol and cortisone performed better than basal tests. The most optimal cutoff values for serum cortisol as measured by immunoassay and for salivary cortisol and salivary cortisone as measured by liquid chromatography–tandem mass spectrometry (LC-MS/MS) were 376, 8.6, and 33.5 nmol/L, respectively, for post-LDSST peak values, and 170, 1.7, and 12.5 nmol/L, respectively, for basal values.

Conclusions:

We established method-specific reference cutoffs for serum cortisol, salivary cortisol, and salivary cortisone during LDSST. Both post-LDSST peak salivary cortisol and cortisone performed well as diagnostic tests for adrenal insufficiency. Their measurements by LC-MS/MS can alleviate problems associated with serum cortisol immunoassays.

Serum but not salivary cortisol levels are influenced by daily glycemic oscillations in type 2 diabetes

Diurnal salivary and plasma cortisol variations are considered valid expression of circadian cortisol rhythmicity. The aim of this study was to assess the reliability of salivary and plasma cortisol and if glycemia and glycemic oscillations may interfere with their concentration. Forty-seven type 2 diabetic patients and 31 controls were studied for glycemic profile and diurnal salivary and plasma cortisol variations on two contemporary samples taken at 08:00 a.m.-11:00 p.m (Late Night, LN). Glucose variability was evaluated in diabetic patients by considering the standard deviation of blood glucose (BGSD) readings, by calculating the mean amplitude of glycemic excursions (MAGEs) and continuous overlapping net glycemic action (CONGA). A significant correlation between LN serum cortisol and morning fasting glycemia (r = 0.78; p = 0.004) was observed in T2DM group but not in the control group (r = 0.09; p = 0.74). While LN serum cortisol significantly correlated with CONGA in diabetic patients (r = 0.50; p < 0.001), LN salivary cortisol did not correlate with any indices of glucose variability. Moreover, a highly significant correlation between LN salivary and LN serum cortisol concentrations was found in control group (r = 0.80; p < 0.001) but not in diabetic patients (r = 0.07; p = 0.62). This study shows for the first time that LN salivary rather than plasma cortisol may give information on the dynamics of adrenal function of type 2 diabetic patients, as it is not significantly influenced by glycemic variations. However, our preliminary results need to be confirmed by further studies with more complete evaluations including many more patients.