Ontario Health Study encourages Ontarians to "be part of something big"

Starting this spring 150,000 Ontarians are being asked to be part of something big – a major population health study that will help scientists understand what causes cancer, cardiovascular disease and other chronic diseases.

The Ontario Health Study opened for enrolment in March. Researchers are sending invitations to hundreds of thousands of households in a handful of communities that are representative of the province’s demographic makeup to recruit a sample large enough to understand a comprehensive range of factors that cause people to develop chronic disease.

The study will follow participants for at least 20 years to create a bank of information that scientists can use to help understand how genetic factors, environment and behaviour work together to affect health over time. The aim of the multidisciplinary team leading the study is to ultimately improve prevention and early detection of a wide range of illnesses.

Three publicly funded organizations are leading the Ontario Health Study: the Ontario Institute for Cancer Research (OICR), funded by the Ontario Ministry of Research and Innovation to conduct research on cancer; Cancer Care Ontario, funded by the Ontario Ministry of Health and Long-Term Care to conduct research and improve cancer services; and the Canadian Partnership Against Cancer, an independent organization funded by the federal government to accelerate action on cancer control. In addition, the Canadian Cancer Society, Ontario Division and the Ontario Agency for Health Protection and Promotion recognize the importance of the study and are endorsing its objectives.

The dataset from the Ontario Health study will be linked to other cohort studies taking place across Canada. In total, 300,000 Canadian adults will participate. Invitations and promotional materials will ask people to “be part of something big,” a slogan that reflects the massive size of the study as well as the significance of the results.

“This is the largest research effort of its kind in Canadian history. The knowledge from this study will be valuable to researchers worldwide, and will also give us specific information about how to detect, prevent and treat chronic diseases here in Ontario,” says Dr. Tom Hudson, President and Scientific Director of the Ontario Institute for Cancer Research, one of several institutes leading the Ontario Health Study.

The principal investigator for the cancer portion of the study is Dr. John McLaughlin, an epidemiologist at Cancer Care Ontario and professor at the University of Toronto who was appointed last year as program leader of OICR’s Ontario Cohort Program. McLaughlin and his colleagues have been planning the study for several years, determining the study design and sampling methods, collaborating with bioinformaticians to develop strategies to collect and manage data, and securing research ethics approval to ensure participants’ privacy is protected.

The study design takes into account Ontario’s demographic and geographic diversity, with study centres in rural and urban areas. Initially, study questionnaires have been translated in French, Chinese and Punjabi to facilitate participation by members of the three largest non-English communities in the province. Other translation services will be available through the use of translators or staff that have knowledge of additional languages spoken in the community where the recruitment centre will be located.

People are invited to a study centre, where they will meet with nurses who explain the purpose of the study and obtain informed consent. The participant then enters personal health information into data-collection kiosks and a number of measurements are taken. At the end of the session, a nurse will give the patient a personalized health report and identify any areas of concern that should be discussed with a family doctor or other primary care practitioner. Participants will also be asked to send in samples of tap water and dust from their homes. A blood sample will also be collected for genetic analysis, along with a urine sample.

All samples and information collected during the next 20 years will be confidential and data will be stored on secure servers; researchers will only be able to access de-identified datasets, which provide health data but not the participants’ names. Participants also have the option of opting out of certain portions of the study or to withdraw their consent at any point during the study. The study has been designed to accommodate a normal rate of drop-out.

The first Ontario Health Study centre opened on March 26 in Mississauga, and more will open throughout 2009. Over the next 20 years, researchers will follow up with participants to track their health status and determine which genetic, environmental and lifestyle characteristics are associated with which diseases.