In the latest National Health and Medical Research Council grants round, Assoc Prof Roach and Dr Sargent have been granted $720,000 over three years to study ‘The impact of seven days of sleep restriction on predicators of Type 2 diabetes’.
This project is a collaboration with Professor Peter Clifton and Professor Jon Buckley from the University of South Australia and Professor Eve Van Cauter from the University of Chicago.
“Type 2 diabetes is a harmful disorder that affects almost one million Australians and costs the community more than $30 billion every year,” Assoc Prof Roach says.
“Poor diet and physical inactivity are regarded as the primary behavioural causes of T2D, but recent evidence suggests that chronic sleep loss, as experienced by over 30% of Australians, may also play an important causal role.
“Laboratory studies have shown that a week of sleep loss severely disrupts endocrine function, and longitudinal epidemiological data indicate that the risk of developing T2D is increased by 95% for people who normally sleep less than six hours per day.
“This is a remarkable figure, given that poor diet and physical inactivity only increase the risk of developing T2D by a comparatively modest 59% and 52%, respectively.
“Most of the laboratory studies in this field have examined the effects of very low sleep doses (i.e. 4–5 hours per day) on endocrine function. These comparisons are important because they have established a causal pathway, but they are of limited practical use because very few people regularly obtain less than 5 hours of sleep per day.
“The next critical advance required in this field is to quantify the impairment in endocrine function that occurs at sleep doses that are within the range experienced by most adults (i.e. 5-9 hours per day).”
Assoc Prof Roach, who is based at CQUniversity’s Appleton Institute in Adelaide, says his project results will be used to design lifestyle interventions for the prevention, delay of onset, and treatment of Type 2 diabetes.