Doctor aims to prevent bone breaks among aged

by Hilary Thomson

Staff writer

It's called the silent thief.

Affecting 1.4 million Canadians, it results in fractures, deformity, disability and is a significant cause of death among the elderly.

Yet many people don't even consider osteoporosis to be a disease, according to European findings.

Endocrinologist Dr. David Kendler hopes to improve the understanding and treatment of osteoporosis in B.C. with the Fractures and Falls Prevention Program, starting at St. Vincent's Hospital this month.

The program, the first in Canada focused on the elderly, will offer clinical care on a referral basis.

Working closely with community groups such as the Osteoporosis Societies of B.C. and Canada, it will also educate doctors, other health care providers and the public.

"This program is one of the few in the world attempting a coordinated approach to falls prevention and osteoporosis therapy," Kendler says. "Often people aren't aware they've got the disease until they've had their first fracture. We're looking at preventive measures to treat the problem before a fracture that could end someone's independence."

More common than breast or ovarian cancer and as common among women as cardiovascular disease, osteoporosis in the elderly costs Canadian taxpayers about $1.3 billion per year, mostly for treatment of fractures.

"The disturbing news is that with baby boomers aging over the next 30 years, the incidence of hip fractures related to osteoporosis is expected to increase by 275 per cent, " says Kendler, who is also a clinical assistant professor in Faculty of Medicine.

By 90 years of age, 30 per cent of women and 15 per cent of men will have suffered a hip fracture. Following a fracture, almost a third of patients are institutionalized.

Characterized by low bone density and deterioration of bone tissue, osteoporosis leads to increased bone fragility and risk of fracture--most often at the spine, wrist or hip. A bone is considered osteoporotic if it has weakened to the point where it may fracture with minimum trauma.

About 20 per cent of hip fracture patients die within the year from complications due to surgery and loss of mobility, says Kendler.

Measuring bone density is key to early detection and treatment. Although risk factors such as gender, age, inadequate calcium in diet or family history of osteoporosis are significant, measuring bone mass is critical.

Bone density reaches a peak around age 20 and is maintained until menopause. After that time, a woman may lose 20 to 45 per cent of her bone mass due to lack of estrogen.

A specially developed X-ray device compares current bone mass measurements to the peak level.

In a simple procedure, the patient lies flat on a table while a mechanical arm, positioned about 10 inches above the table, moves back and forth across the width of the body from knee to chest.

A pencil-thin low radiation X-ray beam is directed vertically through the body. The X-ray unit measures how much of the beam passes through the bone, an indicator of calcium content and fracture risk.

Once the disease has been detected, preventive treatment may include hormone replacement, increased calcium and vitamin D intake or increase in weight-bearing exercise. Some drug therapies can reduce risk of fractures by 50 per cent.

New hormones called selective estrogens may be available next year. These hormones act as estrogen, preventing bone loss and reducing cholesterol, with no apparent increase in risk of breast cancer. Bone-forming agents are also expected to be available soon.