Impact of sleep apnoea variability on atrial fibrillation

Dr Chrishan Nalliah, Macquarie University

2020 Postdoctoral Fellowship

Years funded: 2021-2023

Atrial fibrillation (AF) is the commonest heart rhythm disorder in humans affecting 33.5 million people globally. In addition to huge impacts on patient’s quality of life, it causes heart failure and stroke. We don’t understand why AF occurs. Sleep apnoea is a disorder of sleep characterised by periodic cessation of airflow during sleep and occurs in up to 38% of the community. Sleep apnoea increases the risk of developing AF and is prevalent in up to 50% of AF patients. Studies show that treatment of sleep apnoea is critical to successfully manage AF.

Sleep apnoea diagnosis is based on an overnight sleep study that evaluates a single night’s sleep. However, sleep apnoea severity fluctuates on a night-to-night basis based on individual and environmental factors. Among AF patients with sleep apnoea, the amount of AF a patient has on a particular day is related to the severity of sleep apnoea the previous night. This study will evaluate how variation of sleep apnoea severity on a night-to-night basis impacts AF the following day.

This research will provide valuable insights on how variability of sleep apnoea severity from night to night impacts AF and may impact how we diagnose and manage sleep apnoea in AF patients. Monitoring may be required over multiple nights to reach an accurate diagnosis of sleep apnoea in AF. Secondly, the acute impact of sleep apnoea severity on atrial remodelling will allow us to determine the impacts of sleep apnoea on the heart and highlight those changes that may form a target for therapy. Finally, the current study will provide insight into the link between sleep apnoea severity and stroke risk providing further reason for prompt diagnosis and intervention.