Endocrine Abstracts

Purpose: Dopaminergic system is implicated in the development of sleep disorders, and dopaminergic agents are used in clinical practice to treat daytime sleepiness and sleep disorders. The present study aimed at investigating the effects of hyperprolactinemia and its control with dopamine-agonists (DA) on sleep quality, excessive daytime sleepiness (ESS) and risk of obstructive sleep apnea syndrome (OSAS) in prolactinomas.

Methods: A single-centre study was conducted from July to December 2022: 44 patients with prolactinoma (23 M, 21 W, aged 46,4±14,42 yrs), including 22 with macroprolactinoma, 20 with microprolactinoma and 2 with empty sella, were sex- and BMI-matched with 80 healthy controls (32 M, 48 W, age 34,8± 11yrs). In all participants, 3 questionnaires were administered to investigate sleep disorders (Pittsburgh Sleep Quality Index, PSQI, normal score <5), daytime sleepiness (Epworth Sleepiness Scale, ESS, normal score <10) and OSAS risk (Berlin Questionnaire, BQ, normal score less than 2 categories). In all participants, height, weight and BMI were recorded. In patients, tumour size at diagnosis, PRL at evaluation, treatment duration (TD), CAB dose (CD), and fasting glucose and insulin were evaluated.

Results: Between patients and controls no significant difference was found in the prevalence of sleep disturbances, ESS and OSAS risk. According to patient age, a significant difference (P=0.028) in OSAS risk was found in older patients (age> 56y) as compared to other quartiles. Based on sex, BMI, PRL, TD and CD, no significant difference was found in the prevalence of sleep disturbances, ESS and OSAS risk. In patients, tumour size and BMI were significantly higher in men than in women (P<0.001; P= 0.043). In male patients, PSQI scores directly correlated with tumour size (r=0.45; P= 0.029), whereas ESS scores directly correlated with tumour size (r=0.533; P=0.009), BMI (r=0.51; P=0.012), PRL (r=0.457; P=0.028).

Conclusions: The results of the current study did not confirm an association between sleep disturbances, ESS and OSAS risk and treatment with DA in patients with prolactinomas, but ESS was associated with PRL levels. OSAS risk appeared to be influenced by age and daytime sleepiness by BMI. Interestingly, sleep quality was associated with tumour size, suggesting that the long-term effects of chiasm compression on sleep-wake rhythmicity, observed especially in patients with large pituitary tumours, might negatively impact sleep quality.