Tests to Predict Breaks in Brittle Bones

Routine osteoporosis and bone density exams may not be the best predictor of broken bones in the future

(RxWiki News) Bone health is a critical concern for many aging individuals. Measuring their risks for broken bones is a standard practice, though determining how often such screenings should be done isn't entirely clear.

The current common practice of testing older people's bone density every two years may be too frequent, according to a new study.

"Ask your doctor about how to achieve bone health."

The study's lead author was Sarah Berry, MD, MPH, a specialist in health care for aging people and an investigator at the Institute for Aging Research at Hebrew SeniorLife, a geriatric health and housing center in Boston, Massachusetts.

She and her research colleagues analyzed the health records of 310 white men and 492 white women to determine their need for follow-up tests gauging the amount of strength-building calcium and other minerals in their bones. Such bone tests typically are done using low-dose X-rays.

Thinning bones can lead to full-blown osteoporosis, a disease that makes bones vulnerable to fractures. Most people with the disorder are older and female, though men and younger people can also develop osteoporosis.

Study participants were 75 years old, on average, when their bone density was first measured. They had been enrolled in the Framingham Osteoporosis Study and took three bone density tests between 1987 and 1999, one every four years. After the second tests, the researchers tracked their bone health for an average of 10 years ending in 2009.

During that period, the researchers said that 113 (14.1 percent) of the 802 study participants experienced bone fractures. Among the 113, there were 88 broken hip bones, 33 forearm fractures, 24 spinal fractures and five shoulder fractures, the researchers wrote.

Based on the second bone density tests that reclassified risk of fracture, only 3.9 percent of study participants who were reclassified actually broke a hip. Of those reclassified as at risk for breaking their forearm, spine or shoulder, 9.7 percent experienced such a fracture.

Also, ongoing follow-up tests showed that bone density decreased an average of 0.6 percent per year for the entire group of 802 patients. Overall, study participants ranged from those who gained as much as 5.6 percent in bone density during the study period to those who lost as much as 9 percent of bone density.

These findings led these researchers to conclude that density tests repeated "after four years did not meaningfully improve the prediction of hip or major osteoporotic fracture. Repeating a [bone mineral density] measure within four years to improve fracture risk stratification may not be necessary in adults this age [who are] untreated for osteoporosis."

Carla Perissinotto, MD, of the University of California, San Francisco Department of Medicine Geriatrics Division, told dailyRx News that this study echoes previous ones that asked if there was excessive use of everything from mammograms to prostate cancer screenings.

"We are screening and testing too often, with little data to support the increased frequency of testing," Dr. Perissonotto said. "Over time, as we gather more data, the medical community has realized that prevention is important, but we are still fine-tuning the frequency of testing. Adults over 65 should, therefore, question if they truly need a repeat bone density test even when it is offered after two years. Remember that more testing does not [automatically] equal better health and longer life."

Aside from not being medically necessary for some, the repeated tests also were driving up healthcare costs at a time when many have made cost-cutting a priority, the researchers wrote. They noted that Medicare, the federal health insurance program for people aged 65 and older, covers the costs of bone density tests every two years and does not limit the number of tests for which costs are reimbursed.

According to these researchers, 22 percent of Medicare beneficiaries get another density test within three years of the first test. On average, for that group, the tests were conducted 2.2 years apart.

The researchers added, however, that repeat tests may be crucial for some, namely those who underwent the follow-up bone density tests and broke bones. "For these individuals a repeat screening test provides the opportunity for clinicians to intervene with osteoporosis medications that reduce the risk of fracture, even among persons 75 years or older," the researchers wrote.

This study was published online September 24 in JAMA.

The National Heart, Lung, and Blood Institute and Friends of Hebrew SeniorLife helped fund the study but had no role in study design or data analysis, the researchers wrote.

Some of the researchers have received grants and consulting fees from pharmaceutical manufacturers.

Review Date: 
September 20, 2013