Largest ever Canadian study on osteoporosis informs health policy

Jun 16 2008

Dr David Goltzman and his team from the Research Institute of the McGill University Health Centre (RI MUHC) and McGill University - along with colleagues from across Canada - have issued new recommendations to public health authorities about how to best cope with osteoporosis, a bone disease which leads to increased risk of fracture, particularly in the elderly.

Their recommendations derive from the latest results of the Canadian Multicentre Osteoporosis Study (CaMos), which will be published June 16 in the Canadian Medical Association Journal (CMAJ).

Osteoporosis results from reduced bone mineral density (BMD), disrupted bone microarchitecture and alteration in the distribution and variety of non-collagenous proteins in bone, all of which serve to place sufferers at far greater risk of bone fractures, which can be life-threatening in the elderly. The measure of BMD is the main predictive marker of the disease. "Osteoporosis has enormous impact on public health and on the quality of life of patients," Dr. Goltzman said.

The latest CaMos results confirm that, for women, menopause is a critical period during which bone mineral density decreases in all the bones studied. More specifically: an average decrease of 6.8% over 5 years was observed in the hip. Significant BMD loss also occurs after age 70, mainly in the hip bone. In men, BMD decreases more gradually, although it starts earlier, around the age of 40.

The fact that rapid BMD loss occurs after menopause was already known but had never been previously quantified, while the second period of BMD decline after age 70 is a completely new discovery.

"These findings provide new insight into the public health impact of osteoporosis," Dr. Goltzman explained. "Population aging combined with the potential human and financial consequences of fractures, notably hip fractures represent a major challenge. However, knowing the age at which bone loss is more likely to occur opens up new avenues for preventive measures."

The CaMos study involves nine other centres across Canada that are coordinated from the MUHC in Montreal. It has recruited more than 10,000 participants since 1996. The long duration and the national scale of the project have enabled researchers to determine that participants' BMD varies very slowly in the absence of other risk factors.

"The scope of the CaMos study means that we can produce data that are representative of the entire Canadian population, in order to help improve official recommendations, and to enhance the prevention, diagnosis and treatment of osteoporosis," said Dr Goltzman.

"In light of our results, we think that, in the absence of other risk factors, BMD should be measured every five years, instead of every two years, as is currently the case," he continued. "Of course, this frequency should be modified if the person does have other risk factors.

Dr. David Goltzman is the co-principal investigator of the CaMos project. He is a researcher in the Musculoskeletal Disorders axis at the RI MUHC and Professor of Medicine (Endocrinology/Metabolism) and of Physiology at McGill University's Faculty of Medicine.

The CaMos study is sponsored by the Canadian Institutes of Health Research (CIHR), Merck Frosst Canada Ltd., Eli Lilly Canada Inc., Novartis Pharmaceuticals Inc., the Alliance for Better Bone Health (Sanofi-Aventis and Procter & Gamble Pharmaceuticals Canada Inc.), the Dairy Farmers of Canada and the Arthritis Society of Canada.

About the Canadian Multicentre Osteoporosis Study (CaMos)

Initiated in 1996, CaMos is a prospective, population-based epidemiologic study involving a collaboration of leading Canadian experts, 10 study centres in 7 provinces and more than 10,000 participants across Canada. This largest ever Canadian study on osteoporosis, recognized internationally for its validity and quality, features a sample representative of the Canadian population and a long-term perspective with almost 70% retention after 10 years of follow-up. Study results have helped to inform health policy and improve osteoporosis prevention, diagnosis, and treatment in Canada. For more information on CaMos please visit www.camos.org.

The McGill University Health Centre (MUHC) is a comprehensive academic health institution with an international reputation for excellence in clinical programs, research and teaching. Its partner hospitals are the Montreal Children's Hospital, the Montreal General Hospital, the Royal Victoria Hospital, the Montreal Neurological Hospital, the Montreal Chest Institute and the Lachine Hospital. The goal of the MUHC is to provide patient care based on the most advanced knowledge in the health care field and to contribute to the development of new knowledge.www.muhc.ca

The Research Institute of the McGill University Health Centre (RI MUHC) is a world-renowned biomedical and health-care hospital research centre. Located in Montreal, Quebec, the institute is the research arm of the MUHC, the university health center affiliated with the Faculty of Medicine at McGill University. The institute supports over 600 researchers, nearly 1200 graduate and post-doctoral students and operates more than 300 laboratories devoted to a broad spectrum of fundamental and clinical research. The Research Institute operates at the forefront of knowledge, innovation and technology and is inextricably linked to the clinical programs of the MUHC, ensuring that patients benefit directly from the latest research-based knowledge. The Research Institute of the MUHC is supported in part by the Fonds de la recherche en santé du Québec.

http://www.muhc.ca/research.