October 2013

Bone Density Testing — Reduced Reimbursement and Access Have Led to Fewer Screening Exams
By Kathy Hardy
Radiology Today
Vol. 14 No. 10 P. 28

Dual energy X-ray absorptiometry (DXA) is the gold standard for osteoporosis screening in postmenopausal women, particularly those aged 65 and older. But it’s not just for women, as older men deal with the same issues concerning bone density and have an even greater risk of mortality after a hip fracture.

In addition, DXA may be used as a body mass measurement tool for evaluating lean and fat mass. Sports medicine practitioners also are seeing the benefits of this technology in determining peak performance and training regimens. Finally, software additions to DXA allow imaging of the thoracic and lumbar spine to detect the presence of vertebral fractures. Vertebral fracture assessment (VFA) may be of even greater value than DXA in determining future fracture risk.

However, an increase in the number of DXA applications doesn’t necessarily mean there’s easy access to bone mineral density testing. Clinicians who can afford to offer the test are more likely to control where and when DXA is used today. As with several imaging specialties, a decline in reimbursement in the private practice setting is influencing decisions regarding where patients can go for scans, even though DXA is not considered an advanced imaging modality like MRI and CT.

“DXA scan is something that has been performed by a number of nonradiologists, but with the decrease in reimbursement, specialists who used to do this in their offices can’t afford to offer this service now,” says Jean Weigert, MD, FACR, director of women’s imaging for the Hospitals of Central Connecticut. “Radiologists are adding this to their practices as part of their overall offerings.”

Fewer Office-Based Exams
Private practitioners such as OB/GYNs, rheumatologists, and endocrinologists who offered DXA scans in their offices, as well as smaller women’s imaging centers, are eliminating this service, creating a shift from point-of-service care to hospitals and larger radiology centers as the primary locations for bone density testing. According to Andrew Laster, MD, FACR, CCD, an International Society for Clinical Densitometry (ISCD) past president and a rheumatologist in Charlotte, North Carolina, whose practice has included DXA scans since 1986, 70% of all DXA scans were performed in clinicians’ offices in 2002, with the remaining percentage picked up by hospitals. He says those numbers are shifting away from private practices and toward hospitals.

“The biggest issue in DXA today is the decline in reimbursement in the nonfacility setting,” he says. “DXA took the biggest hit. With reimbursement having dropped 63% in the last seven years and below what it costs to do the test, this has created problems for physicians. Many primary care doctors and some specialists in private practice are giving up their machines.”

According to information provided by the ISCD, Congress first cut DXA payments in 2007, along with Medicare payments for other imaging services, as part of the Deficit Reduction Act of 2005. Further cuts, phased in over time, occurred when the Centers for Medicare & Medicaid Services reduced payments for work done by physicians in the course of interpreting DXA scan results. Under the Affordable Care Act, DXA payments were restored to 70% of the 2006 level, bringing reimbursement back up to nearly $100. But that increase lasted for only two years. In the end, a provision to increase Medicare payments for DXA was not included in legislation enacted this past January.

Standards for DXA testing were enacted by Congress in 1997 as the Bone Mass Measurement Act and codified by the CMS. They allow for DXA testing for individuals who are estrogen deficient, individuals with a vertebral abnormality such as osteopenia or fracture, individuals on steroids with prednisone equivalent of 7.5 mg/day for three or more months, individuals with hyperparathyroidism, and as a monitoring response to FDA-approved drug therapy.

The ISCD also sets standards for when DXA should be used. Indications for bone mineral density testing call for DXA scans for women aged 65 and older and for postmenopausal women younger than the age of 65 who have the following risk factors for low bone mass: low body weight, prior fracture, high-risk medication use, and a preexisting disease or condition associated with bone loss. In addition, women who are in the process of menopausal transition and have clinical risk factors for fracture should undergo regular DXA scans. Women discontinuing estrogen also should be considered for bone density testing, according to the indications listed above.

Determining bone density baseline numbers is the principle use of DXA, says Bradford Richmond, MD, FACR, CCD,  a radiologist with the Cleveland Clinic in Cleveland, Ohio. Educating the patient as to the importance of determining bone health is important since many patients do not understand why they should undergo the first scan. Like high blood pressure, if the silent symptoms are not found, the consequences—stroke for high blood pressure and fracture for low bone density—are the first signs of the diagnosis. Once a fracture occurs the risk of subsequent fracture significantly increases and compounds with each additional fracture.

“Like mammography for breast cancer, DXA is performed to diagnose and intervene as early as possible to avoid the fractures and subsequent morbidity and mortality associated with them,” Richmond says. “Some people do not believe in the need for DXA since low bone mass/osteoporosis is a silent disorder until the first fracture. To have the testing and educating them is essential.”

Also, in a comparison to mammography, MedStar Georgetown University Hospital internist Andrea Singer, MD, clinical director of the National Osteoporosis Foundation, says early diagnosis is a key in preventing fractures in an older population. That level of detection could be negatively impacted with a decrease in scan locations. “If they can’t continue to offer DXA scans, you’re limiting access to a test for a preventable and treatable disease,” Singer says. “As with any preventable disease, early diagnosis is key. You’re preventing fractures that could be life-changing for patients.”

Not Just Women’s Imaging
The ISCD also notes that a bone density test is indicated for men aged 70 and older if they have a risk factor for low bone mass. However, radiologists and other physicians alike believe that men are underserved when it comes to fracture forecasting. “This is an issue for men over age 70 and particularly for men who have had a hip or nonvertebral fragility fracture or have other risk factors such as use of certain drugs for the treatment of prostate cancer. ”

Additionally, DXA scan protocols don’t provide specifics regarding when follow-up testing should be done, Richmond says. This is a concern, particularly when it comes to patients following an osteoporosis medication regimen. In some cases, follow-up is required because of the protocol related to a particular medication.

“DXA scan follow-up is controversial,” he says. “ISCD recommends a one- to two-year follow-up after initiating treatment. If treatment is not started, a two-year follow-up to determine if density has changed significantly is a common practice. After the first follow-up, if the BMD [bone mineral density] is normal, the appropriate subsequent scan interval is controversial. Follow-up for patients treated for low bone mass is important to ensure compliance and efficacy of treatment. Follow-up scans should take into consideration the response expected from the treatment.”

As practices either eliminate DXA scans from their service set or reduce the number of locations where it is offered, patient access to DXA becomes limited. Even though DXA is part of the standard “welcome to Medicare” exam, Laster, who also is the chair of the ISCD’s public policy committee, says fewer patients are undergoing the test, primarily because of access issues. He notes a 12.6% decrease from 2008 to 2011 in nonfacility offices providing DXA scans, with a total 8% decrease in scans only partially offset by the increase in DXA testing in the hospital. The declines in the practice setting are larger—30% to 60% in more rural states, he says. “Despite the public education regarding osteoporosis, we’re not getting to all the people who need DXA scans,” he says.

Limiting Access
Education and training for medical professionals is another factor in the shifting DXA provider picture. The American Registry of Radiologic Technologists (ARRT) and the ISCD offer formal DXA certification. For physicians, there is no formal certification requirement for the CMS or most third-party payers. However, if radiology practices or hospital radiology departments are performing more DXA scans, then it is important that technologists performing the scans and radiologists reading the results are ISCD certified, according to Weigert. “Radiologists need to be trained to read densitometry scans as well as endocrinologists and other specialists,” she says. “It’s not just about reading a number off a chart. You need to know that the patient was scanned properly. You also need to know the limitations of DXA and if an alternative scan such as quantitative CT might be necessary. It isn’t as simple as people think it is.”

Since DXA scans are not unique to one specialty, Laster says certification is a good way to standardize the process and better ensure quality results. “Proficiency varies,” he says. “Any practice that doesn’t place a high value on DXA scans will end up with bad results. You can get a misdiagnosis, resulting in prescribed medications that the patient doesn’t really need.”

Good communication among all clinicians involved also takes on greater importance as specialists or primary physicians who order DXA scans are no longer performing them. Weigert says the person reading the scan results should know whether the patient has any preexisting conditions or diseases, what treatments he or she may be undergoing, and what medications he or she currently is taking. All practitioners involved—from referring physicians to radiologists—need to provide input to reach the proper diagnosis. It’s just as easy to miss an osteoporosis diagnosis or diagnose something incorrectly. “Misdiagnosis can go both ways,” Weigert says. “You need to look at the patient’s clinical situation along with the scan. Brittle bones don’t necessarily mean the patient has osteoporosis. If you’re going to put people on medication, then low bone density screening needs to be done carefully.”

For example, she notes that when a patient’s DXA scan Z score is low, the cause could be endocrine related rather than an issue of bone density, as the Z score compares the patient’s bone density level to other patients of the same age. She says information should be included in the patient’s report to help determine treatment options, particularly when it comes to prescribing medications. “Clinicians need to work as a team,” she says. “Quality of life and bone health go hand in hand.”

Patients with multiple issues (eg, diabetes, heart disease, osteoporosis) can fall into a dangerous situation if all aspects of their health are not considered, according to Singer. “In cases where a patient is dealing with several medical issues, the question is how can we make sure osteoporosis makes it to the list of conditions to be treated and followed up.  Patients with chronic medical conditions have limited time with doctors who are handling their osteoporosis treatment as well. While often their other medical issues require immediate attention, it shouldn’t come at the expense of fracture prevention,” Singer says.

Removing the DXA scan from the specialist’s office also can cause a delay in patients receiving test results, Richmond adds.

In many instances, Laster says, the addition of VFA assessment to DXA will enhance fracture risk prediction and improve patient care. Many vertebral fractures cause no pain or are not imaged since back pain is so common. In many individuals with osteopenia or low bone mass, unless you were aware that they had a prior facture, their calculated fracture risk would be low enough to not warrant drug therapy.

Back to Primary Care
Laster says organizations with a vested interest in bone density health and in preventing future fractures need to work with their legislators to improve reimbursement for DXA to “help get DXA back into primary care. DXA isn’t just for radiology or women’s health. It’s a primary care issue. To have something this common and not be able to test for it is like taking blood pressure cuffs out of offices and then eyeballing a patient’s blood pressure.”

In the end, Weigert points out that with an aging population, the issue of bone density and the need for scanning isn’t going to go away. “Maybe it was done too often in the beginning, but now we know more about it,” she says. “We know more now and with more education, we can better apply this technology.”

— Kathy Hardy is freelance writer and editor based in Phoenixville, Pennsylvania. She writes primarily about women’s imaging topics for Radiology Today.