Hypothalamus has a key role in multiple vital functions, including regulation of sleep-wake cycles. Oxytocin (OT), a neurohormone synthetized in the hypothalamus, has a wide range of physiological functions, including a putative role in improving sleep quality. Hypothalamic and pituitary damage (HPD) is associated with a clinically relevant OT deficient state and multiple and severe comorbidities including poor sleep quality, that have a well-known negative impact on general health and quality of life (QoL). Several factors may coexist in the pathophysiology of sleep disorders (SD) in HPD and SD might be a keystone in the persistence of some of the comorbidities observed in HPD. Therefore, appropriate identification and understanding of the mechanisms contributing to SD in HPD is mandatory to choose adequate preventive strategies and treatment. This project is aimed to (1) identify the prevalence of SD in HPD, (2) to determine OT role in sleep quality and (3) to identify potential mechanisms and mediators of sleep quality and their associations with clinical outcomes in patients with HPD with the ultimate goal of identifying preventive and therapeutic targets. We will use a controlled cross-sectional design of patients with HPD and sex-, BMI-, age- matched controls and an innovative cross-disciplinary approach bridging neuroendocrinology, psychology, neurophysiology, neuroimaging, nuclear medicine and neuroophthalmology disciplines to learn about the prevalence of SD in HPD and to disentangle the underpinning mechanisms behind SDs in HPD. The results of this project will be an extremely important step towards optimizing therapy for patients with HPD who have higher mortality and poor QoL despite appropriate hormone replacement therapy.