Stomach CT scans may help find osteoporosis: Study

Reuters Health: Doctors can use a patient’s abdominal CT scans to also check for signs of the bone-weakening disease osteoporosis, according to a new study.

The researchers, who published their findings in the Annals of Internal Medicine on Monday, compared patients’ CT scans to their dual-energy X-ray absorptiometry (DXA), which is traditionally used to diagnose osteoporosis.

“What we found is that there is pretty good correlation,” said the study’s lead author Dr. Perry Pickhardt, professor of radiology at the University of Wisconsin School of Medicine and Public Health in Madison.

The idea, say the researchers, is doctors can use patients’ CT scans that are ordered for another reason – such as looking for tumours – to also check for signs of osteoporosis. That may spare the patients from additional testing and additional costs.

In an editorial accompanying the study, however, experts wrote that using CT scans to gauge bone density could lead to some people being incorrectly diagnosed, particularly if people at low risk are tested.

In this study, the average age was about 59 years old - six years younger than the age at which the US Preventive Services Task Force, a government-backed panel, recommends all women begin being screened for osteoporosis. The disease affects over 12 million Americans over 50.

The panel also suggests younger women at an increased risk for bone fractures should be screened, but there’s no recommendation for men of any age.

Despite DXA scans being safe and cost effective, Pickhardt and his colleagues say the test is underused. CT scans, however, are considered overused – with more than 80 million performed in the US during 2011.

For the new study, the researchers analysed test results from 1,867 patients, who had both types of scans performed within six months of each other over a 10-year period, to see if their CT scans showed osteoporosis as well as the DXAs.

Dr. Sumit Majumdar, who wrote an editorial accompanying the new study, said a lower threshold for bone density would catch most cases of osteoporosis and limit “incidentaloporosis” – incorrect osteoporosis diagnoses “discovered” while doctors were looking for something else.

At the lower threshold, the researchers found 9% of those diagnosed with osteoporosis were misdiagnosed.

Pickhardt said the screenings would have to target the right groups of people to prevent over-diagnosis.