Heart Rate Variability and Interoception in Periodic Limb Movements in Sleep: Interference with Psychiatric Disorders?

Abstract

Periodic limb movements in sleep (PLMS) are a prevalent disorder characterized by rhythmic, involuntary movements of the lower limbs, such as dorsiflexion of the ankle and extension of the big toe, occurring in periodic intervals during sleep. These movements are often linked to disrupted autonomic nervous system (ANS) activity and altered interoception. Interoception involves perceiving internal bodily states, like heartbeat, breathing, hunger, and temperature, and plays a crucial role in maintaining homeostasis and the mind-body connection. This review explores the complex relationships between PLMS, heart rate variability (HRV), ANS dysregulation, and their impact on psychiatric disorders. By synthesizing the existing literature, it provides insights into how ANS dysregulation and altered interoceptive processes, alongside PLMS, contribute to psychiatric conditions. The review highlights the potential for integrated diagnostic and therapeutic approaches and presents a cause-and-effect model illustrating the mutual influence of psychiatric disorders, ANS dysregulation, PLMS, and interoception.

Keywords: autonomic nervous system; cardiovascular interoception; heart rate variability; periodic limb movements in sleep; psychiatric disorders.

Figure 1

The intricate interplay between psychiatric disorders, ANS/HRV dysregulation, PLMS, and interoception; ANS—autonomic nervous system, HRV—heart rate variability, PLMS—periodic limb movements in sleep. Note: At the core of this interconnected web lies a bidirectional relationship. Psychiatric disorders contribute to ANS and HRV dysregulation, which, in turn, influence the manifestation of PLMS. Simultaneously, PLMS can exacerbate psychiatric symptoms, creating a feedback loop. Interoception—the perception of internal bodily sensations—acts as a pivotal link, influencing and being influenced by both psychiatric disorders and ANS dysregulation. This circular relationship underscores the dynamic nature of the interactions, emphasizing the mutual influence and feedback loops among these elements, illustrating the multifaceted nature of the relationship between psychiatric health, autonomic function, sleep movement disorders, and the perception of internal bodily states.

Figure 2

RLS initiates a chain of events leading to PLMS, sleep fragmentation, and sleep deprivation; RLS—restless leg syndrome, PLMS—periodic limb movements in sleep. Note: These events disrupt the ANS and alter interoception. The compromised ANS and impaired interoception contribute to disrupted neurogenic cardiac regulation, potentially leading to cardiovascular disease. This closed-loop sequence highlights the interdependence and sequential impact of RLS on cardiovascular health.