An interpretation of osteoporosis is no longer a guarantee of future bone fractures and loss of independence. Advances in all aspects of osteoporosis have turned the outlook toward optimism for patients, physicians, and those involved with clinical bone densitometry.

Figure 1. Depiction of typical rate of bone mass growth and loss over a lifetime.

However, as the population’s longevity increases, osteoporosis, with age as a major risk factor, expands further as a major disease in the United States and the world (Figure 1). Today, more than 30 million Americans are at risk. In the new millennium, the population over 65 years old will multiply; therefore, we must become more aware of the facts and leave behind the myths surrounding osteoporosis.

Osteoporosis has been labeled the silent thief because it robs bones of strength without the patient’s awareness. The problem with underdiagnosis of osteoporosis is the burden that it places on a health care system because of the cost of fractures, particularly the far-from-silent hip fractures. In the mid 1990s, the cost of hip fractures alone was greater than $10 billion; by the year 2040, that cost could mushroom to $140 billion. The survival of the health care system depends on the implementation of new strategies for the prevention, diagnosis, and treatment of osteoporosis.

This monograph will focus on the changes that have turned years of osteoporosis research into positive clinical and economic outcomes for all.

BONE REMODELING

The skeleton is an organ that provides critical physiological functions. The more bone mass we have, the stronger the structure; the less bone mass, the weaker the architectural integrity, the more prone to silent fractures-expressed in loss of height-and the greater likelihood of devastating hip fractures. However, bone’s primary physiological role is to be a reservoir for the essential mineral calcium. The process that governs this need for calcium is termed bone remodeling, which is in line with the architectural role of the skeleton. As calcium is needed, endocrine and cellular processes release the mineral from the extracellular matrix of the skeleton. On the other hand, when we have the opportunity to store calcium, it is added to growing bone within discrete sites, termed bone remodeling units. This yin and yang of bone is continuous throughout life: slanted for growth up to age 30 and tilted for loss afterward. It is this delicate balance that dictates one’s current level of bone mass. The older the individual, the more at risk for bone loss, osteoporosis, and fracture.

Due largely to this multifunctionality inherent in the skeleton, normal processes and certain diseases and their treatment subtract skeletal integrity. Therefore, it is important to identify the status of the skeleton in discrete groups of people. Age-related and disease-accelerated bone loss threatens structural stability. This frailty becomes the true functional definition of osteoporosis, increasing fracture risk.

Table 1. Risk factors for osteoporosis.

Today, it is possible to prevent and accurately diagnose, as well as treat, osteoporosis, offering the potential to translate these advances into a successful disease management business.

Too many Undiagnosed

Building awareness of osteoporosis in the lay and medical community is both the key and the problem. The initiation of patient management for those at risk for osteoporosis has changed dramatically over recent years. The National Osteoporosis Foundation in 1998 recommended, for the first time, the use of bone densitometry for women over 65 and those under 65 if they have risk factors other than menopause (Table 1). Used in this manner, bone mineral density (BMD) testing becomes the keystone in the determination of intervention. Although interpretive guidelines for BMD have been established by the World Health Organization (Table 2, page 41), each patient’s personal risk factors, especially previous fracture history, should dictate treatment prior to specific cutoff points.

Table 2: WHO criteria for osteoporosis.

No one specialty has established its dominance in the treatment of osteoporosis, leaving the market open to any specialty. Classically, as a metabolic bone disease, it resided in the office of endocrinologists, but their intervention is no longer a requirement to obtain efficacious results. Today, for many reasons, OB/GYNs have begun to use the new pharmaceuticals as a primary tool for their peri- and post-menopausal women (see Table 3). Since OB/GYNs see women annually, are involved with critical decision-making at the time of menopause, and monitor other preventive tests such as yearly mammograms, a bond of trust has maneuvered them into a critical role for bone health management.

Table 3: Current pharmaceuticals for treating osteoporosis.

The largest group of individuals at risk is postmenopausal women, due to their changing estrogen status and its typically devastating effect on the overall level of bone mass throughout the skeleton. However, the loss of skeletal structure can begin much earlier than that, due to inadequate calcium intake, smoking, inactivity, and certain drug uses (Table 1; Table 5 can be viewed? in the online version of this article at www.imagingeconomics.com ). Moreover, the presence of a vertebral fracture, usually found by chance, or having a family history of fractures  increases the risk of further fractures.

Table 5: List of diseases and their treatments that alter bone health.

The potential population at risk can be projected by reviewing the following facts: bone loss increases with age (Figure 1, page 40); the population is aging; and individuals today will live longer than their parents. In the United States, it has been estimated that 30 million people have low bone mass and are at risk. By the year 2040, that number is expected to balloon to greater than 90 million.

While hip fracture is the most devastating outcome of osteoporosis, vertebral fracture and its consequences are more pervasive and troubling. Loss of bone in the spine often leads to slow compression of the spine throughout the column, resulting in height loss, shortness of breath, and sometimes a dramatic change in body shape. Identifying these individuals recently has been addressed in the ability of the bone densitometer to accurately measure structural change without the need of a lateral radiograph. This advantage employs the bone densitometer as a tool for diagnostic observations of structural change within the lumbar and thoracic spine. The ability to identify silent deformity before a full-fledged compression fracture occurs improves the health system’s ability to have an impact on outcomes by prescribing pharmaceutical interventions, and provides a point of care for the patients during an appointment for a bone density test.

BONE DENSITOMETRY: The business

A key to any business plan for an imaging service should be the inclusion of prevention education for all patients and physicians involved in the continuum of bone health management.

For many patients, osteoporosis is asymptomatic until a fracture occurs. But it is no longer necessary to wait for a fracture to occur before treating the disease. Due to the sensitivity and accuracy of current bone mass measurement instruments, it is possible to diagnose and treat the disease well before a fracture event occurs. This preventive guideline should be the primary mission and hallmark of bone health management in the new millennium.

Figure 2: Flow chart for the use of bone density screening and bone density diagnostic testing.

The first line of attack on osteoporosis is prevention in the young and newly adolescent groups, and identification of risk factors in older adults and senior citizens. Herein lies the rub for those involved in the business of clinical densitometry.

The diagnostic algorithm (Figure 2 can be viewed in the online version of this article at www.imagingeconomics.com ) for determining who needs testing and who needs additional testing in order to make a clinical decision is important to understand. First, the clinician needs to consider the result of bone density testing in the context of other risk factors. Screening for bone density in wrists, heels, or fingers is a factor on the list of risk factors, but should not be confused as being a diagnostic test. That aspect of bone health management needs to be clarified and put in perspective.

Table 4: Comparison of bone densitometry techniques.

Dual energy x-ray absorptiometry (DXA) remains the gold standard for the identification and diagnosis of fracture risk. In 2002, there are a number of instruments available (Table 4) that measure BMD with high precision and accuracy. Other technologies that measure BMD in the peripheral skeleton (eg, wrists, heels) can aid in the identification of those at risk for bone loss, but these are classified as screening tests, not as diagnostic tests.

Screening tests usually measure the peripheral skeleton, such as the  phalanges, the forearms, or the calcaneus (heel). Modalities include ultrasound- or x-ray-based instruments and can be found in physician’s offices, at health fairs, or as mobile units that visit senior centers. As the word implies, screening should be used as a safe, quick, accurate assessment of bone density as a complement to personal risk analysis. If the result of a screening test shows low bone density, then it is appropriate to refer that individual for a diagnostic DXA bone density test of the axial skeleton: the whole body, the lumbar spine, or the proximal femur.

As noted above, the identification of personal risk factors is useful, but does not confirm a diagnosis of osteoporosis. It may be a first step for both the individual and the physician in moving forward in a focused evaluation (Figure 2 can be viewed in the online version of this article at www.imagingeconomics.com ). Just as the knowledge of an individual’s health status is essential in making any clinical evaluation of bone health status, changes in bone mass also occur as a primary or secondary response to disease or therapy (Table 5 can be viewed in the online version of this article at www.imagingeconomics.com ). Long-term use of steroids, thyroid surgery, and treatments for organ transplantation, high cholesterol, and immune disorders all represent increased risk factors for osteoporosis.

Since there is a direct association between loss of bone mass and fracture risk, any instrument that measures bone mass density will be helpful in identifying patients at risk for increased bone loss or low bone density. However, the sensitivity and accuracy of DXA instruments make them the only available tools for follow-up and monitoring treatment responses. The principal reasons for a bone density test are:

1. To confirm a diagnosis of osteoporosis as a result of a fracture.

2. To assess fracture risk.

3. To establish a baseline measurement to follow the effect of treatment and/or hormone replacement therapy.

REIMBURSEMENT ISSUES IN BMD

Table 6: Indications for a bone density test.

In 1997, President Clinton signed the bill that established what came to be called the Bone Mass Measurement Act, which provided for uniform coverage under Medicare Part B for all services after July 1, 1998. The bill authorized testing for the “qualified individual” who falls into one of five diagnostic categories (Table 6 can be viewed in the online version of this article at www.imagingeconomics.com ).

Table 7: Commonly used procedural codes and diagnostic codes.

The payment from Medicare and other carriers requires the communication of diagnostic testing codes or CPT (Current Procedural Terminology), HCPCS (Healthcare Common Procedure Coding System), and ICD-9 (International Classification of Diseases, ninth revision) codes. The use of these codes provides insurance carriers and Medicare with a standardized description of what testing was performed and why (Table 7).

In 2002, there can be no response other than to market this service to referring physicians as well as consumers. Be certain to define the services offered; describe the technology utilized; and develop a protocol for referrals for those patients with clinically significant results.

Figure 3: A paradigm for the successful osteoporsis center.

It is clear that word-of-mouth marketing by satisfied patients and referring physicians will increase future referrals. In today’s competitive market, it is important to distinguish an imaging center from those maintaining the status quo. Figure 3, which can be viewed in the online version of this article at www.imagingeconomics.com , depicts a workable paradigm for a successful osteoporosis center business. As a Bone Health Center, its functions must include:

1. High-quality bone densitometry using state-of-the-art DXA, maintained and used by certified technologists.

2. Bone health education and counseling provided to each patient by a trained nurse or individual schooled in the current information on osteoporosis prevention, treatment, and interpretation of bone densitometry.

3. Service to the community for building awareness of osteoporosis. The community must be thought of as the public and the physicians, who all need to be constantly updated on research advances in osteoporosis.

4. (If the director is a physician) A conscious effort must be made and continuously clarified that your mission is to work with referring physicians as a partner, not a competitor, regardless of your status as an osteoporosis expert.

The continuing focus on these goals and customer (the patient and referring physician) satisfaction will establish your center as the resource for bone health information in your community. And with that unique status, your business will thrive.

Michael T. DiMuzio, PhD, is president, Bone Health Management Inc, Lincolnshire, Ill, and executive director, The North Shore Osteoporosis Center, Deerfield, Ill.