The Woolcock Institute of Medical Research

Elizabeth Machan is an early career researcher and senior lecturer from the University of Sydney. She is a Woolcock research affiliate and completed her PhD in obesity management in patients living with obstructive sleep apnea under the supervision of Prof Ron Grunstein. Elizabeth’s PhD work was related to the development of behavioural interventions focused on nutrition and exercise for patients with sleep disordered breathing. This work was successfully translated to the real world through an implementation grant conducted at Royal Prince Alfred Hospital, which was navigated during the COVID-19 pandemic.

Since then, Elizabeth’s research has broadened substantially and she now leads a programme in hypersomnolence and non-pharmacological interventions.

There are three central sleep disorders of hypersomnolence, narcolepsy type 1 (NT1), narcolepsy type 2 (NT2) and idiopathic hypersomnia (IH). These disorders substantially impact quality of life and are typically managed with pharmacotherapy which often causes side effects or is ineffective. Neither effective novel interventions nor non-pharmacological treatments have been rigorously explored (aside from scheduled napping and optimisation of sleep hygiene). Elizabeth’s programme of research aims to learn more about both diet and exercise therapies in people living with central sleep disorders of hypersomnolence. These conditions have lacked attention to date when it comes to lifestyle interventions and it is critical we learn more about how exercise and diet can help to manage these conditions.

She has supervised two honours students who have worked on a broader project related to exercise and hypersomnolence. This qualitative study relates to exercise and symptom management, its interaction with medications and people’s perception of exercise as an adjunct therapy to manage their condition. This work is currently being extended by a third honours student to inform the development of exercise recommendations specific to people living with hypersomnolence through a national survey and Delphi ranking project.

Elizabeth was recently awarded funding by the American Academy of Sleep Medicine to run a clinical trial to test the feasibility (recruitment, adherence, tolerability, attrition) of a whole-food diet (WFD - removal of ultra processed foods), compared with a whole-food ketogenic diet (WFKD - very low carbohydrate version of WFD). This study, known as The COMPANION Study, is also supported by the Sydney Health Partners Clinical Academic Group for Sleep Health.

COMPANION is being conducted within the Woolcock Sleep and Circadian Research group, with Joshua Holley as the PhD student leading this project, and Francis Cheong as the study coordinator. Joshua’s PhD will investigate whether improvements in symptoms of daytime sleepiness, metabolic health and quality of life outcomes can be enhanced with a WFD or WFKD. Further, this mixed methods approach will examine the implementation context, barriers and facilitators to follow this diet and the changes in symptoms experienced. Francis works as a Clinical Sleep Research Assistant in both sponsored and investigator-led clinical trials, mainly in the narcolepsy and idiopathic hypersomnia population.

Recruitment for The COMPANION Study is still open, so please share the link to the study with your circles.

Find out more

• Our Sleep and Circadian Research group