Heavy smokers with osteoporotic bone density on low-dose CT lung cancer screening scans have more than triple the risk of vertebral fracture within two years compared to those with normal bone density, suggesting that the same scan used to detect lung cancer can identify individuals at elevated fracture risk and enable earlier osteoporosis treatment.
- Heavy smokers with osteoporotic bone density on LDCT scans face 3.4 times higher risk of vertebral fracture within two years
- Study analyzed 21,856 heavy smokers aged 55-74 years from the National Lung Screening Trial using automated bone mineral density analysis
- Two-year vertebral fracture incidence was 0.9% for normal bone density, 2.0% for low bone mass, and 5.9% for osteoporotic density
- The 5.9% fracture rate in osteoporotic smokers exceeds treatment thresholds recommended by current osteoporosis guidelines
- Opportunistic screening during routine LDCT lung cancer screening could enable earlier osteoporosis detection and treatment while reducing healthcare costs
Heavy smokers with osteoporotic bone density on low-dose CT scans face more than triple the risk of vertebral fracture within two years compared to those with normal bone density, according to a study published October 27 in Radiology.
A group from University Medical Center Freiburg in Germany applied automated volumetric bone mineral density (vBMD) analysis to existing low-dose CT (LDCT) lung cancer screening scans from a large cohort of heavy smokers, with findings suggesting the same scan used to detect lung cancer can identify individuals at elevated fracture and mortality risk, noted lead author Maximilian Löffler, MD, and colleagues.
"An opportunistic strategy may support earlier detection of osteoporosis and fracture risk, with potential benefits for both patient outcomes and health care costs," the group wrote.
Although LDCT lung cancer screening is increasingly implemented for heavy smokers worldwide, the prognostic value of bone health data embedded in those scans has not been rigorously quantified in large prospective cohorts, according to the researchers. In individuals who undergo regular LDCT of the chest, dual screening for lung cancer and osteoporosis could be valuable, as risk factors for cancer and osteoporosis, such as smoking and advanced age, overlap, they added.
To investigate the prognostic value of the approach, the researchers retrospectively analyzed data from 21,856 participants from the CT arm of the U.S.-based National Lung Screening Trial. Participants were heavy smokers aged 55 to 74 years old with at least 30 pack-years of smoking history.
They used SpineQ software version 1.0 (Bonescreen, Munich, Germany) to automatically classified thoracic and lumbar vBMD from baseline LDCT as normal (≥ 120 mg/cm³), low bone mass (80 to ≤ 120 mg/cm³), or osteoporotic (< 80 mg/cm³). Outcomes were one- and two-year incident vertebral fractures on follow-up LDCT and six-year all-cause mortality, adjusted for demographics, comorbidities, and baseline fractures.
Images from opportunistic osteoporosis screening using automated software (SpineQ; Bonescreen) at low-dose CT lung cancer screening in a 62-year-old man. At baseline, this participant in the National Lung Screening Trial currently smoked (47 pack-years) and had a body mass index of 25.7 (calculated as weight in kilograms divided by height in meters squared), a volumetric bone mineral density of 73 mg/cm3 (averaged over T10–T12 using calibration parameters for a GE Medical Systems CT scanner and acquisition at 120 kVp), and a grade 3 (G3) vertebral fracture at T8. At 1-year follow-up, he had an incident grade 2 (G2) vertebral fracture at T6. Images from left to right are as follows: unenhanced axial low-dose CT image with 2.5-mm section thickness used as input imaging data; software-generated sagittal reformations in the full field of view and cropped to the spine, with labeled vertebrae and detected fractures; and three-dimensional renderings of the spine segmentation (regions of interest for the extraction of CT attenuation values are shown in red).RSNA
Importantly, the researchers noted that the 5.9% two-year fracture incidence in osteoporotic heavy smokers exceeds the threshold at which current guidelines recommend antiosteoporotic drug therapy, suggesting that opportunistic LDCT screening could translate into actionable treatment decisions, the researchers wrote.
"Future work should assess whether integrating automated bone density analysis into LDCT workflows improves fracture prevention and, potentially, reduces mortality," the authors concluded.
In an accompanying editorial, Miriam Bredella, MD, of NYU Langone Health and NYU Grossman School of Medicine, wrote that the principal challenge is now implementation rather than measurement.
"The critical next step is therefore a pragmatic implementation trial: one that automatically identifies patients with high risk, routes results into a defined care pathway, and determines whether this approach increases appropriate osteoporosis evaluation and treatment and, ultimately, reduces fractures without excessive testing or overtreatment," she noted.
Löffler et al provide an important step toward that goal, Bredella concluded.
The full study is available here.
