Hemodialysis disrupts basic sleep regulatory mechanisms: building hypotheses.

Abstract

The proposition that hemodialysis may induce alterations in the sleep-wake cycle is based on two clinical observations: (a) Patients on dialysis frequently sleep during and after dialysis, and (b) the procedure often is associated with temperature elevations. A review of pertinent literature showed that sleepiness and temperature are physiologically related, and that these two variables are important indicators of sleep and circadian regulatory processes. To describe possible associations among hemodialysis, body temperature, and sleepiness; to assist in building hypotheses; and to provide direction for future research. Three exploratory studies were performed to investigate (a) dialysis-associated elevations in body temperature, (b) changes in body temperature patterns across the day, and (c) alterations in daytime sleepiness. The current study demonstrated that many patients manifest dialysis-associated episodic elevations of body temperature, changes in the circadian pattern of body temperature, and increases in daytime sleep propensity. In the context of the Two-Process Model of Sleep Regulation, these alterations provide a parsimonious explanation for the poor subjective sleep quality, prolonged sleep latency, and daytime sleepiness reported by these patients. These preliminary studies lead to the suggestion that hemodialysis may disrupt basic sleep regulatory mechanisms, and that further investigation in this area is warranted.