Late-night Salivary Cortisol a Poor Approach for Detecting Cushing’s in Obese Patients

Assessment of late-night salivary cortisol (LNSC) levels is a poor diagnostic tool for detecting Cushing’s disease in obese patients, a new study from Germany shows.

The test demonstrated a particularly poor sensitivity in obese people, meaning it will often suggest a patient has Cushing’s disease when that is not the case — called a false-positive.

The study, “Specificity of late‑night salivary cortisol measured by automated electrochemiluminescence immunoassay for Cushing’s disease in an obese population,” appeared in the Journal of Endocrinological Investigation.

Although excessive weight gain is a common symptom of Cushing’s disease, existing indications advise clinicians to test for Cushing’s in obese people only if the disease is clinically suspected.

The utility of measuring LNSC for Cushing’s disease screening is well established. However, differences in assays, sample collection methods, and controls have led to a great variability in the proposed reference ranges and cut-off values. Also, according to the Endocrine Society, the influence of gender, age, and co-existing medical conditions on LNSC concentrations is still unclear.

Regarding obesity, data on the specificity of assessing late-night salivary cortisol levels is contradictory, as some studies found no differences while others reported lower specificity compared to healthy individuals.

An additional factor complicating LNSC measures in obese people is the prevalence of type 2 diabetes mellitus (T2DM), which may also lead to elevated cortisol levels.

Research showed a high rate of false-positive LNSC measurements in obese patients with poorly controlled type 2 diabetes. Also, in patients with recently diagnosed diabetes, investigators found that LNSC had very low specificity — the proportion of patients with Cushing’s who test positive — and a poor predictive value.

Recent reports showed a high diagnostic accuracy using automated electrochemiluminescent assays (ECLIA) in patients with Cushing’s disease. These methods use special labels conjugated to antibodies that produce light when they bind to a specific target.

The research team used an ECLIA assay to test the specificity of LNSC in obese patients both with and without diabetes. The investigators also intended to establish a reference range and cut-off value for this diagnostic approach.

Adults who requested weight loss treatment were included in the study, including 34 patients with a confirmed diagnosis of Cushing’s and 83 obese people, defined as having a body mass index (BMI) of at least 35 kg/m2. Forty healthy individuals were also analyzed.

Eight out of the 34 Cushing’s patients had a BMI within the obese range, which correlates with an overlap in patients awaiting bariatric surgery for weight loss, the investigators observed.

All subjects underwent LNSC assessment at 11 p.m. Results revealed significant differences in mean LNSC values — 19.9 nmol/L in Cushing’s disease patients, 10.9 nmol/L in obese subjects, and 4.7 nmol/L in those of normal weight.

Compared to healthy and obese participants, measuring LNSC in Cushing’s disease patients had a maximum sensitivity of 67.6% and a specificity of 85.4%. This was lower than prior data from obese patients with two features of Cushing’s disease.

The cut-off value for detecting Cushing’s was 12.3 nmol/L, which is in line with other studies “and underlines the importance of an evaluation with an obese cohort vs. [Cushing’s disease],” the investigators wrote.

Results did not show an association between BMI, type 2 diabetes, and LNSC for all groups.

“In our obese cohort, we found that LNSC assayed by ECLIA had a low specificity in the diagnosis of [Cushing’s disease],” the researchers wrote. “However, the clear advantage of LNSC over other tests is the simple and stress-free sampling method.”

From https://cushingsdiseasenews.com/2018/03/29/nighttime-salivary-cortisol-poor-approach-detect-cushings-disease-obese-patients/

Late-night salivary cortisol often fluctuates widely in Cushing’s disease

Among patients with new, persistent or recurrent Cushing’s disease, researchers observed cortisol levels that fluctuated widely over 6 months, with measurements falling into the normal range more than 50% of the time for a few patients, according to findings from a prospective study.

“Cortisol levels, as represented by late-night salivary cortisol, in Cushing’s disease patients without variable symptoms fluctuate much more widely than many endocrinologists may realize,” Laurence Kennedy, MD, FRCP, chairman of the department of endocrinology, diabetes and metabolism at the Cleveland Clinic, told Endocrine Today. “In patients with recurrent or persistent Cushing’s disease, the late-night salivary cortisol can be normal much more frequently than has been appreciated.”

Kennedy and colleagues analyzed late-night salivary samples (between 11 p.m. and midnight) from 16 patients with confirmed Cushing’s disease for up to 42 consecutive nights between January and June 2014 (age range, 27-62 years). Researchers defined normal late-night salivary cortisol as between 29 ng/dL and 101 ng/dL.

Within the cohort, eight patients had a new diagnosis of Cushing’s disease and underwent transsphenoidal surgery; eight patients had recurrent or persistent Cushing’s disease.

Researchers observed at least three peaks and two troughs in 12 of the 16 patients, and late-night salivary cortisol levels were in the normal range on at least one occasion in 14 patients (all patients with recurrent/persistent disease and six of eight patients with new disease). Only two of the 16 patients exhibited fluctuations that were deemed cyclical, according to researchers, with the interval between peaks approximately 4 days, they noted.

In five of the eight patients with recurrent or persistent disease, the lowest late-night salivary cortisol measurement was at or below the limit of detection on the assay and approximately 1 in 3 measurements were in the normal range, researchers found. Four patients had normal measurements more than 50% of the time.

Additionally, six of the patients with recurrent or persistent disease had measurements in the normal range on two consecutive nights on at least one occasion, two patients had six such measurements in a row, and one had 31 consecutive normal levels, according to researchers.

In six patients with newly diagnosed Cushing’s disease with at least one normal late-night salivary cortisol measurement, the maximum levels ranged from 1.55 to 15.5 times the upper limit of normal.

“First, widely fluctuant cortisol levels in patients with Cushing disease do not appear to be associated with fluctuating symptoms, at least in our patient population,” Kennedy said. “Second, you need to be careful drawing conclusions on the efficacy of potential medical treatments for Cushing’s disease based on only one or two late-night salivary cortisol levels, given the extreme variation that occurs in the untreated patient. Third, diagnosing recurrent or persistent Cushing’s disease can be challenging at the best of times, and, though it is felt that late-night salivary cortisol may be the best test for early diagnosis, it may require more than the suggested two, three or four tests on successive nights to make the diagnosis.”

Kennedy said better tests for diagnosing Cushing’s disease are needed, adding that investigating the potential utility of salivary cortisone could be useful. – by Regina Schaffer

For more information:

Lawrence Kennedy, MD, can be reached at Cleveland Clinic, Department of Endocrinology, Diabetes and Metabolism, 9500 Euclid Ave., Cleveland, OH 44195; email: kennedl4@ccf.org.

Disclosures: The authors report no relevant financial disclosures.

From https://www.healio.com/endocrinology/adrenal/news/in-the-journals/%7Bf9721377-6a2a-401c-a16d-2d4624233b63%7D/late-night-salivary-cortisol-often-fluctuates-widely-in-cushings-disease

Who’s at Risk for Cushing’s?

by Kristen Monaco
Contributing Writer, MedPage Today

Researchers have developed a new method to assess specific populations for Cushing’s syndrome, based on results from a multicenter study.

The prospective cohort study evaluated at-risk patients for Cushing’s syndrome to create a novel type of scoring system in order to better predict the development of disease, stated lead author Antonio León-Justel, PhD,of the Seville Institute of Biomedicine in Spain, and colleagues.

Cushing’s syndrome is identified by an excess of cortisol and/or glucocorticoids in the blood, which can result in myriad negative health outcomes, including an increased risk of death and morbidity, according to the study in The Journal of Clinical Endocrinology & Metabolism.

Because Cushing’s syndrome (CS) is complex and difficult to diagnose, there is a necessity for new methods to assess at-risk populations in order to mitigate the rising prevalence of the disorder, the authors noted.

“The diagnosis of CS might pose a considerable challenge even for experienced endocrinologists since there are no pathognomonic symptoms or signs of CS and most of the symptoms and signs of CS are common in the general population including obesity, hypertension, bone loss, and diabetes,” the senior author, Alfonso Leal Cerro, MD, toldMedPage Today via email. “Routine screening for CS remains impractical due to the estimated low prevalence of the disease. However this prevalence might be higher in at-risk populations.”

The authors screened a total of 353 at-risk patients from 13 different hospitals across Spain between January 2012 and July 2013 to measure cortisol variability from saliva samples.

At-risk populations, which the authors note have a higher prevalence of Cushing’s syndrome, included individuals with type 2 diabetes, hypertension, and osteoporosis.

The patients screened in the study were each identified as having at least two of the risk factors for Cushing’s syndrome: high blood pressure (defined as taking two or more drugs and having a systolic blood pressure over 140 mmHg and/or a diastolic blood pressure over 90 mmHg), obesity (body mass index >30), uncontrolled diabetes (HbA1c>7.0%), osteoporosis (T-score ≥ -2.5 SD), and virilization syndrome (hirsutism) with menstrual disorders.

The researchers used clinical and biochemical methods of assessment. Clinical methods included inspection of physical characteristics, such as muscle atrophy, purple striae, and/or facial plethora. Biochemical methods included collecting saliva and blood samples from participants to test cortisol levels using a chemiluminescence method. Each individual was identified as either negative for hypercortisolism (late-night salivary cortisol [LNSC] ≤ 7.5 nmol/L and dexamethasone suppression test [DST] ≤ 50 nmol/L) or positive for hypercortisolism (LNSC > 7.5 nmol/L and DST > 50 nmol/L).

Univariate testing indicated the following significant characteristics to be positively correlated with the development of Cushing’s syndrome:

  • Muscular atrophy (15.2, CI 95% 4.48-51.25);
  • Osteoporosis (4.60, 1.66-12.75); and
  • Dorsocervical fat pad (3.32, 1.48-7.5).

A logistic regression analysis of LNSC values also showed significant correlation between Cushing’s syndrome and the following top three characteristics:

  • Muscular atrophy (9.04, CI 95% 2.36-34.65);
  • Osteoporosis (3.62, CI 95% 1.16-11.35); and
  • Dorsocervical fat pad (3.3, CI 95% 1.52-7.17).

Roberto Salvatori, MD, professor and medical director of the Johns Hopkins Pituitary Center, who was not involved with the study, commented to MedPage Today in an email: “Any endocrinologist would proceed with careful Cushing biochemical evaluation in the presence of the clinical features (muscular atrophy, osteoporosis, and dorsocervical fat pad) that are well known to be associated with hypercortisolism. Of notice, the odds ratio is further increased by an abnormal late-night salivary cortisol, which is already a screening test for hypercortisolism.”

The researchers used their results to develop an equation to determine the level of risk a patient has for developing Cushing’s syndrome, taking into account factors for osteoporosis, dorsocervical fat pads, muscular atrophy, and LNSC levels.

Although the study was able to develop a comprehensive risk model for the syndrome, when tested against the prevalence for Cushing’s syndrome in the subject group, the equation generated a total of 56 false-positive and 25 true-positive results. Overall, the researchers wrote, 83% of patients were accurately classified as belonging to the at-risk population when using the equation.

Because the newly developed equation for identifying at-risk individuals involved factors that are relatively easy to test for, the authors noted that clinical application is broad and cost-effective in a primary care setting.

“We would like to test the scoring system in different clinical settings such as primary care or hypertension clinics,” Leal Cerro said. “Primary care would be a particularly interesting setting since it might significantly decrease the time to diagnosis, something critical to avoid an excessive exposure to glucocorticoid excess and consequent deleterious effects.”

Salvatori said that while the study was a good start at shedding light on some of the unknowns about Cushing’s syndrome, more research is required. “The real question in my mind is when does a non-endocrinologist need to suspect Cushing in a general medicine, orthopedic, or other clinic? When the internal medicine residents ask me about guidelines for ‘who to screen for hypercortisolism in my clinic,’ I am unable to provide an evidence-based answer.”

The study was funded by a grant from Novartis Oncology, Spain.

León-Justel and Leal Cerro disclosed financial relationships with Novartis Oncology, Spain.

  • Reviewed by F. Perry Wilson, MD, MSCEAssistant Professor, Section of Nephrology, Yale School of Medicine and Dorothy Caputo, MA, BSN, RN, Nurse Planner

LAST UPDATED 08.15.2016

Screening tool accurately predicts Cushing’s syndrome in most at-risk patients

León-Justel A, et al. J Clin Endocrinol Metab. 2016;doi:10.1210/jc.2016-1673.

A scoring system based on clinical signs and a late-night salivary cortisol test accurately predicted Cushing’s syndrome in at-risk patients, with only one missed case, according to recent findings.

In a prospective, multicenter study, Antonio León-Justel, PhD, of the biochemistry department at the Hospital Universitario Virgen del Rocío in Seville, Spain, and colleagues analyzed data from 353 patients treated in endocrinology units in 13 university hospitals in Spain between 2012 and July 2013. All participants had at least two of five features compatible with Cushing’s syndrome, including obesity, hypertension, poorly controlled diabetes,hirsutism with menstrual disorders and osteoporosis; none of the included patients was referred to clinic with the suspicion of Cushing’s syndrome. All patients underwent late-night salivary cortisol and serum cortisol measurements after a low-dose (1 mg) dexamethasone test; those with discordant results were followed until December 2014 (mean follow-up time, 22.2 months).

Within the cohort, 26 (7.4%) patients were diagnosed with Cushing’s syndrome (20 adrenocorticotropic hormone-dependent; six of adrenal origin). In univariate logistic regression analysis, researchers found that muscular atrophy (OR = 15.2), followed by osteoporosis (OR = 4.6), dorsocervical fat pad (OR = 3.32), absence of obesity (OR = 0.21) and absence of type 2 diabetes (OR = 0.26), were associated with Cushing’s syndrome; late-night salivary cortisol values were also related (OR = 1.26). However, after multivariable adjustment, researchers found that muscular atrophy (OR = 9.04; 95% CI, 2.36-34.65), osteoporosis (OR = 3.62; 95% CI, 1.16-11.35) and dorsocervical fat (OR = 3.3; 95% CI, 1.52-7.17) remained as independent variables with Cushing’s syndrome.

“Obesity and type 2 diabetes displayed a negative association with [Cushing’s syndrome],” the researchers wrote. “These results might seem paradoxical a priori, but we want to stress that in our analyzed cohort, the prevalence of obesity and diabetes was exceedingly high (likely reflecting the reasons for referral to endocrinology units).”

In receiver operating characteristic (ROC) analysis, researchers determined that a cutoff value of 9.17 nmol/L for late-night salivary cortisol provided the best results, with an area under the curve of 0.893 (P < .001), a sensitivity of 88.5% and specificity of 83.2%.

Researchers developed a risk-scoring system, determining cutoff values from a ROC curve. The estimated area under the ROC curve was 0.93 (P < .001), with a sensitivity of 96.2% and specificity of 82.9%.

“Selecting this cutoff value of four, 271 of 327 subjects (83%) without [Cushing’s syndrome] were correctly identified, while only 1 of 26 [Cushing’s syndrome] cases was missed,” the researchers wrote. “Our model yielded 56 false positives.

“Although all the assessments were performed by specialists (endocrinologists) in our study, this scoring system could be easily tested in independent cohorts and different settings such as primary care or hypertension clinics,” the researchers wrote. “At the very least, our diagnostic prediction model could be used as a framework for future studies and potential improvements in diagnostic performance.” – by Regina Schaffer

Disclosure: Leon-Justel and another researcher report receiving a research grant from Novartis Oncology, Spain.

From http://www.healio.com/endocrinology/adrenal/news/in-the-journals/%7B50d3d398-c8fe-41e9-b815-87626bfe8a4b%7D/screening-tool-accurately-predicts-cushings-syndrome-in-most-at-risk-patients

Elevated late-night salivary cortisol may indicate recurrent Cushing’s disease

Carroll TB, et al. Endocr Pract. 2016;doi:10.4158/EP161380.OR.

 

Elevated late-night salivary cortisol may serve as an early biochemical marker of recurrent Cushing’s disease, and prompt intervention may result in clinical benefits for people with Cushing’s disease, according to recent study findings.

According to the researchers, late-night salivary cortisol level is more sensitive for detecting Cushing’s disease recurrence compared with urinary free cortisol or a dexamethasone suppression test.

Ty B. Carroll, MD, assistant professor at the Medical College of Wisconsin Endocrinology Center and Clinics in Menomonee Falls, and colleagues evaluated 15 patients (14 women; mean age, 49.1 years) with postsurgical recurrent Cushing’s disease (mean time to recurrence, 3.3 years) after initial remission to determine the performance of urinary free cortisol and late-night salivary cortisol measurements for detecting recurrent Cushing’s disease.

Participants were identified as having Cushing’s disease between 2008 and 2013; there was no standard for follow-up, but after remission confirmation participants were followed at least every 6 months after surgery for 2 years and then annually thereafter. Late-night salivary cortisol was the primary biochemical test to screen for recurrence, and follow-up tests with a dexamethasone suppression test, urinary free cortisol or other tests were performed if late-night salivary results were abnormal or if suspicion of recurrence was high.

Of the cohort, 80% had normal urinary free cortisol (< 45 µg/24 hours) at recurrence. Primary transphenoidal adenoma resection was performed in all participants. Evidence of pituitary adenoma on MRI at the time of recurrence was present in seven of 12 participants with normal urinary free cortisol and two of three participants with abnormal urinary free cortisol. Normal renal function was present in all participants, and 14 underwent testing with late-night salivary cortisol, dexamethasone suppression test and urinary free cortisol.

Of participants with normal urinary free cortisol at recurrence, nine had an abnormal dexamethasone suppression test (cortisol 1.8 µg/dL), and all had at least one elevated late-night salivary cortisol measurement (> 4.3 nmol/L). Mean late-night salivary cortisol was 10.2 nmol/L, and mean urinary free cortisol was 19.9 µg/24 hours.

Therapy for recurrent Cushing’s disease was administered in 11 of the 12 participants with abnormal urinary free cortisol. Adrenocorticotropic hormone (ACTH)-staining pituitary adenoma was confirmed in three participants who underwent repeat transphenoidal adenoma resection. Pharmacotherapy was administered to seven participants with normal urinary free cortisol, and two additional participants underwent bilateral adrenalectomy.

Abnormal dexamethasone suppression test was found in two participants with elevated urinary free cortisol at the time of recurrence, and two participants had confirmed abnormal late-night salivary cortisol. All three participants with elevated urinary free cortisol at the time of recurrence underwent therapy.

“This study has shown potential clinical benefit of either surgical or medical therapy in recurrent [Cushing’s disease] patients with elevations of [late-night salivary cortisol] and normal [urinary free cortisol],” the researchers wrote. “We believe that the outcomes observed in this retrospective case series suggest that the risk/benefit ratio of early treatment needs to undergo a more rigorous prospective evaluation utilizing [late-night salivary cortisol] elevation as an early biochemical marker of recurrent [Cushing’s disease].” – by Amber Cox

Disclosure: Carroll reports being a consultant for Corcept Therapeutics. Please see the full study for a list of all other authors’ relevant financial disclosures.

From http://www.healio.com/endocrinology/adrenal/news/online/%7B9ea4e4ed-6428-49b8-9b2a-11462cb21349%7D/elevated-late-night-salivary-cortisol-may-indicate-recurrent-cushings-disease

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