Using the two most specific markers of bone resorption, the Bone Resorption Assessment measures bone loss accurately and inexpensively.

By discriminating between patients with high and low bone turnover - two subgroups which benefit from different therapeutic approaches - health care professionals can prescribe appropriate treatments and monitor patient compliance and treatment effectiveness.¹

The Bone Resorption Assessment is also invaluable in evaluating osteoporosis and the bone diseases associated with arthritis, metabolic bone disease, and cancer.

The noninvasive urine analysis assays pyridinium crosslinks. Pyridinium crosslinks consist of deoxypyridinoline (DPD) and pyridinoline (PYD), which have been found to be more specific for bone resorption than other assays for tissue collagen metabolites, such as telopeptides.³

Background

Osteoporosis is the most common bone disorder in America.⁴ More than 50% of healthy American women aged 30-40 are likely to develop vertebral fractures as they age due to osteoporosis.⁵ Unfortunately, treatment is only partially successful (at best) once progressive bone weakening has occurred. It is important to identify women in danger and those who are currently losing bone at an accelerated rate so that effective treatment can begin when the therapeutic burden is prevention instead of reversal of bone loss.

Bone is a dynamic tissue, continually formed and resorbed. Until a woman is in her early 20s, she synthesizes more bone than is resorbed. Eventually, aging shifts this balance, and most women over age 30 slowly lose bone.

Osteoporosis results when the normal cycle of bone remodeling is interrupted. In normal remodeling, bone cells called osteoclasts carve out cavities in the bone surface, which are filled by osteoblasts to form new bone.

In bones affected with osteoporosis, new bone formation does not keep up with bone removal, leaving the bone progressively brittle. As bone is lost, the skeleton continues to have a normal composition, but it becomes porous, hyper-mineralized and more fragile.

A woman may lose 30% to 50% of her cortical bone thickness over a lifetime.⁶ Although both men and women slowly lose bone as they age, some women lose bone much more rapidly around menopause. It has been assumed that menopause initiates this more rapid bone loss.

Preventive measures such as exercise, diet, and nutritional supplements are known to help prevent and partially reverse the effects of osteoporosis. If preventive measures are to be initiated prior to the onset of rapid bone loss, they must beconsidered by young women-those in their 30s and 40s.

Impact of osteoporosis

More than 25 million Americans, primarily women, are candidates for developing osteoporosis.⁷ The disease leads to 1.5 million fractures per year.⁷ The World Health Organization has described osteoporosis as an "impending epidemic" and estimates that by 2050 the incidence of hip fractures worldwide will reach 6.3 million annually.⁸

In the United States, a third of all women 60 and older have spinal compression fractures. Such fractures cause varying degrees of pain, deformed spine, and height loss and are associated with loss of appetite, heartburn, bloating and difficulty in breathing.⁴

Metabolic bone and joint diseases (osteoarthritis, rheumatoid arthritis, cancer, endocrine disorders, Paget's disease and amenorrhea) account for an additional 12 million cases of accelerated bone loss per year.

The future health and economic impact of established osteoporosis is expected to be substantial. In many Western societies, patients with hip fractures occupy more hospital beds than patients with any other disease.⁹ In the United States, more than 300,000 hip fractures occur each year due to osteoporosis.⁷ Half of the patients with hip fractures cannot walk independently afterward, frequently developing complications such as pneumonia or blood clots.

Excluding chronic alcoholics, fewer men than women develop osteoporosis. It is estimated, however, that men comprise up to 1/3 of all hip fractures.⁶ Men generally have greater bone mass, consume more calcium, and exercise more than comparably-aged women.