Why is this study being done?

Sleep disruption, sleep deprivation, sleep disorders and disrupted circadian rhythms are commonplace in 21st-century Ontario, and yet we are only beginning to understand their impact on our health and well-being.

The Ontario Sleep Health Study is an exciting new initiative that is helping to answer this question.

The goals of the Ontario Sleep Health Study are:

  1. To understand better the impact of sleep and circadian rhythms on the common health problems faced by Ontarians, particularly diabetes, heart disease, cancer, and brain diseases like stroke and Alzheimer’s disease.
  2. To understand better how our genes affect our sleep and circadian rhythms.

Between 2014 and 2018, we are inviting up to 4,000 Ontarians to measure their sleep and circadian rhythms in the comfort of their own homes. These measurements will then be linked to health information contained in public health databases, as well as to health information and blood samples collected by the Ontario Health Study.

By building a better understanding of the links between genes, sleep and circadian rhythm disruption, and the health and well-being of Ontarians, the Ontario Sleep Health Study may open the door to new sleep-related interventions to prevent diseases like diabetes, heart disease, cancer, and brain diseases like stroke and Alzheimer’s disease, and in so doing improve the health and well-being of Ontarians for generations to come.

Research team

Dr. Andrew Lim

Dr. Lim is the principal investigator of the Ontario Sleep Health Study. He is a scientist in the Hurvitz Brain Sciences Research Program at Sunnybrook Research Institute, an assistant professor of neurology at the University of Toronto and a neurologist at Sunnybrook Health Sciences Centre in Toronto. He completed an MD and residency in neurology at U of T, a clinical sleep fellowship at the Beth Israel Deaconess Medical Center in Boston and a master’s degree in clinical investigation at Harvard Medical School.

The focus of his practice is disorders of sleep and circadian biology. His research uses statistical genetic, neuropathological and epidemiological studies to understand better the genes and neural circuits that regulate individuals’ biological clocks and their sleep. The aim is to understand how disruption of sleep and biological rhythms, as seen in conditions such as insomnia, shift work and jet lag, affect individuals’ risks for common medical disorders like Alzheimer’s disease, Parkinson’s disease, heart disease and stroke.

Giselle Kraus

Giselle Kraus is the study coordinator of the Ontario Sleep Health Study. Before starting in this role, Giselle worked as a research coordinator for four years in the mood disorders program of the McGill University Health Centre in Montreal, Canada. She has completed a master of science in psychiatry and a bachelor of arts in psychology, both at McGill University.


The Ontario Sleep Health Study is supported by the Canadian Institutes of Health Research; the Heart and Stroke Foundation of Ontario; Ontario Ministry of Research, Innovation and Science; ResMed Corp; and Philips-Respironics.

Canadian Institute of Health ResearchHeart and Stroke Foundation of Ontario

Ontario Ministry of Research, Innovation and ScienceResMed Corp.Philips-Respironics

Contact information

Telephone: 416-480-5143
Address: Sunnybrook Health Sciences Centre, 2075 Bayview Ave., AB 211, Toronto, ON M4N 3M5