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Neuroendocrinology and Pituitary

SUN-020 - Objective Sleep and Circadian Rest-Activity Assessment in Cushing'S Syndrome using Extended Actigraphy

Sunday, June 14, 2026
9:00 AM - 4:00 PM CT
Location: ENDOExpo; Poster Floor
Disclosure(s):
Elisabeth Nowak, MD: Esteve: Advisory Board (), Speaker's honoraria ()


Background: Fatigue and sleep disturbances are frequent early symptoms of endogenous Cushing’s syndrome (CS), often persist after remission, and reduce quality of life. Although highly prevalent, the objective features of sleep disturbances in CS and the factors influencing them remain insufficiently defined.

Objectives: This study pursued three aims: (1) to evaluate the diagnostic value of actigraphy in patients with suspected endogenous hypercortisolism, (2) to investigate and compare sleep and circadian rest-activity patterns in patients with CS in long-term remission with either persistent or recovered adrenal insufficiency, and (3) to explore associations between late-night salivary cortisol (LNSC) and actigraphy-based sleep measures.

Methods: This was a prospective, single-center cohort study conducted at LMU Hospital Munich with two patient cohorts. Cohort 1 included individuals undergoing diagnostic work-up for suspected CS, while cohort 2 comprised patients with CS in remission, stratified according to adrenal recovery. All participants underwent continuous wrist actigraphy for 21 days (ActTrust 2, Condor Instruments), collected daily LNSC samples, and completed the Munich ChronoType Questionnaire.

Results: Of the patients evaluated for suspected CS, 16 were diagnosed with active disease, while CS was excluded in 13. Actigraphy demonstrated comparably impaired sleep quality in both groups, characterized by increased nocturnal wakefulness, low sleep efficiency, and fragmented but largely preserved circadian rest-activity rhythms. No actigraphy-derived parameter distinguished active CS from excluded CS (all p>0.1), apart from an earlier chronotype in active CS (p=0.022). In the remission cohort (n=23), sleep quality and circadian rest-activity patterns were similarly affected in patients with persistent (n=13) and recovered (n=10) adrenal insufficiency, with no significant differences in nocturnal wakefulness, sleep efficiency, chronotype, or social jetlag (all p>0.1). Daily LNSC showed marked intra- and interindividual variability across all groups: constantly elevated in active CS, partially elevated in excluded CS, and frequently elevated in adrenal insufficiency receiving hydrocortisone replacement therapy, likely reflecting replacement pharmacokinetics. Overall, correlations between actigraphy-derived sleep parameters and LNSC were weak (r < 0.3) and inconsistent.

Conclusion: Prolonged actigraphy identified clinically relevant sleep impairment in all patients evaluated for CS but did not allow discrimination between active and excluded disease. In remission, impaired sleep persisted regardless of adrenal recovery. LNSC was highly variable and did not serve as a good proxy for sleep quality.

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