Differences in Circadian Sleep Parameters as a Function of Gender in Patients on the Waiting List for Liver Transplantation.

Sleep is a critical component of health, yet its role is underexplored in patients awaiting organ transplantation. This study examined sex-based differences in circadian sleep indicators among liver transplant candidates. Fifty patients (40 men (M) and 10 women (W)) on the waiting list at Hospital Clínico Universitario Virgen de la Arrixaca (Murcia, Spain) wore the Kronowise K6 wrist device on their nondominant wrist for 1 week pre-transplantation. Data were analysed using Kronowise 100 software (Kronohealth, Spain). Forty-two variables related to sleep quality and circadian rhythms were assessed via Student's t-test. Significant differences between sexes emerged in actual sleep time (p = .03), sleep efficiency (p = .022), total movement time (p = .011), and blue light exposure before sleep (p = .04). Men exhibited longer sleep duration, greater movement, and higher pre-sleep light exposure, whereas women demonstrated superior sleep efficiency. The midpoint of sleep-related peak values occurred later in women. Despite shorter sleep duration, women achieved better sleep quality, potentially due to reduced exposure to blue light before sleep, which was up to 2.5 times less than that of men. This disparity likely reflects differing pre-sleep behaviors, such as screen use. Additionally, women's core sleep phase was delayed by approximately 30 minutes. These findings suggest sex-specific differences in circadian sleep profiles among liver transplant candidates. Given men's less favorable sleep hygiene, targeted interventions may be warranted to improve pre-transplant sleep health.