Stressful situations such as disease and surgery lead to sleep disorders (Mouch et al., 2020). The literature reports that sleep disturbances during the perioperative period increase the risk of neurocognitive disorders, are associated with postoperative delirium and cognitive decline, and that improving sleep quality may mitigate these adverse effects (O'Gara et al., 2021). Sleep disorders are common in postoperative patients, with disruptions in regular sleep patterns such as altered REM–non–REM cycles and reduced total sleep duration. Neuronal networks that promote awareness after surgery can be readily activated by painful stimuli. Certain cytokines released postoperatively—tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6)—have been associated with decreased REM sleep duration and increased deep sleep (NREM, slow–wave sleep) duration. Elevated stress hormone release (e.g., adrenocorticotrophic hormone and cortisol) and heightened sympathetic activity may further disrupt sleep. Consequently, major surgery may result in more severe sleep disturbances (Sipilä & Kalso, 2021).

Cranial surgical interventions are commonly performed for conditions such as brain tumors, cerebral hemorrhage, and aneurysms, which exert considerable effects on patients' lives and cause high levels of stress (Arslan et al., 2017). In patients with intracranial aneurysms, pre- and postoperative assessments have shown increased sleep latency, persistent sleep latency, and total wakefulness duration, along with decreased overall sleep quality (Virkkala et al., 2018). Similarly, a study conducted with surgical patients, including those undergoing brain surgery, demonstrates that higher anxiety levels are associated with poorer sleep quality (Oral et al., 2022). In a study comparing patients who had undergone surgery for aneurysmal subarachnoid hemorrhage or meningioma with healthy controls, patients reported poorer subjective sleep, longer sleep onset times, and increased deep sleep duration. They also exhibited higher morning cortisol levels and, although not statistically significant, worse psychological states (Gerber et al., 2016). Overall, the literature indicates that studies investigating sleep quality and psychological status in patients after cranial surgery are limited (Gerber et al., 2016; Virkkala et al., 2018). Therefore, the aim of this study was to examine the relationship between sleep quality, perceived stress, and socio-demographic and clinical characteristics in patients who had undergone cranial surgical intervention.