Hemodialysis disrupts basic sleep regulatory mechanisms: Building hypotheses

Background: The proposition that hemodialysis may induce alterations in the sleep-wake cycle is based on two clinical observations: (a) Patients on di alysis frequently sleep during and after dialysis, and (b) the procedure of ten is associated with temperature elevations. A review of pertinent litera ture showed that sleepiness and temperature are physiologically related, an d that these two variables are important indicators of sleep and circadian regulatory processes. Objectives: To describe possible associations among hemodialysis, body temp erature, and sleepiness; to assist in building hypotheses; and to provide d irection for future research. Methods: Three exploratory studies were performed to investigate (a) dialys is-associated elevations in body temperature, (b) changes in body temperatu re patterns across the day, and (c) alterations in daytime sleepiness. Results: The current study demonstrated that many patients manifest dialysi s-associated episodic elevations of body temperature, changes in the circad ian pattern of body temperature, and increases in daytime sleep propensity. in the context of the Two-Process Model of Sleep Regulation, these alterat ions provide a parsimonious explanation for the poor subjective sleep quali ty, prolonged sleep latency, and daytime sleepiness reported by these patie nts. Conclusions: These preliminary studies lead to the suggestion that hemodial ysis may disrupt basic sleep regulatory mechanisms, and that further invest igation in this area is warranted.