Measuring cortisol levels in saliva multiple times a day is a convenient and useful way to determine the best course of treatment for patients with Cushing’s syndrome, a preliminary study shows.
The research, “Multiple Salivary Cortisol Measurements Are a Useful Tool to Optimize Metyrapone Treatment in Patients with Cushing’s Syndromes Treatment: Case Presentations,” appeared in the journal Frontiers of Endocrinology.
Prompt and effective treatment for hypercortisolism — the excessive amount of cortisol in the blood — is essential to lowering the risk of Cushing’s-associated conditions, including infections, cardiovascular disease, and stroke.
These therapies not only suppress cortisol levels, but also avoid adrenal insufficiency (where not enough cortisol is produced) and restore the circadian rhythm, which is disrupted in Cushing’s patients. However, effective medical treatment requires monitoring cortisol activity throughout the day.
Salivary measurements of cortisol are a well-known method for diagnosing and predicting the risk of recurrence of Cushing’s syndrome. The method is convenient for patients and can be done in outpatient clinics. However, the medical field lacks data on whether measuring cortisol in saliva works for regulating treatment.
Researchers analyzed the effectiveness of salivary cortisol measurements for determining the best dosage and treatment timing of Cushing’s patients with Metopirone.
The study included six patients, three with cortisol-secreting masses in the adrenal glands and and three with ACTH (or adrenocorticotropin)-secreting adenomas in the pituitary glands, taking Metopirone. Investigators collected samples before and during treatment to assess morning serum cortisol and urinary free cortisol (UFC). Patients also had salivary cortisol assessments five times throughout the day.
Saliva samples were collected at 6 a.m. (wake-up time), 8 a.m. (before breakfast), noon (before lunch), 6 p.m. (before dinner), and 10 p.m. (before sleep).
Other studies have used UFC assessments to monitor treatment. However, the inability of this parameter to reflect changes in diurnal cortisol requires alternative approaches.
Results showed that although UFC was normalized in five out of six patients, multiple salivary cortisol measurements showed an impaired diurnal cortisol rhythm in these patients.
Whereas patients with cortisol-secreting adrenocortical adenoma showed elevated cortisol levels throughout the day, those with ACTH-secreting pituitary adenoma revealed increased levels mainly in the morning. This finding indicates that “the significance of elevated morning cortisol levels is different depending on the disease etiology,” the researchers wrote.
In a prospective case study to better assess the effectiveness of performing multiple salivary cortisol assessments, the research team analyzed one of the participants who had excessive cortisol production that was not controlled with four daily doses of Metoripone (a daily total of 2,250 mg).
Results revealed that cortisol levels increased before each dosage. After the patient’s treatment regimen was changed to a 2,500 mg dose divided into five daily administrations, researchers observed a significant improvement in the diurnal cortisol pattern, as well as in UFC levels.
Subsequent analysis revealed that performing multiple salivary cortisol measurements helps with a more precise assessment of excess cortisol than analyzing UFC levels, or performing a unique midnight salivary cortisol collection, the researchers said.
Although more studies are required, the results “suggest that multiple salivary cortisol measurements can be a useful tool to visualize the diurnal cortisol rhythm and to determine the dose and timing of metyrapone [Metopirone] during the treatment in patients with [Cushing’s syndrome],” the researchers wrote.
Future studies should include a larger sample size, evaluate changes over a longer term, use a standardized protocol for treatment dosing and timing, and evaluate changes in a patient’s quality of life, the investigators said.