Clinical Variables Linked to Trabecular Bone Score
A number of clinical variables are associated with trabecular bone score.
SEATTLE — New study data have linked a higher trabecular bone score (TBS) with certain clinical variables, including younger age and male sex.
The research was presented at the American Society for Bone and Mineral Research (ASBMR) 2015 Annual Meeting.
TBS, which is generated from spinal bone mineral density (BMD) scans, is a recently approved measure of bone texture that is associated with bone microarchitecture and fractures.
“TBS is a new clinical tool that, in addition to bone density and FRAX, can enhance our identification of individuals who are at increased risk of fractures, which rise exponentially with age,” said study investigator Meryl LeBoff, MD, who is a professor of medicine at Harvard Medical School.
“As there were significant differences in TBS between men and women, further TBS cut-offs may have different predictive fracture risk between the two sexes.”
Dr LeBoff, who is also chief of the calcium and bone section and director of skeletal health and osteoporosis section at Brigham and Women's Hospital in Boston, noted that both diabetes and obesity are associated with increased fracture risk in the setting of high bone density tests. It is hoped that TBS could help clinicians better determine the best treatment regimens to prevent osteoporosis and fractures.
Dr LeBoff, Ann Ross, MD, who is also with Brigham and Women's Hospital, and colleagues investigated whether baseline TBS differs by sex, race/ethnicity, BMI, and other clinical variables using data from the ancillary Vitamin D and Omega-3 Trial (VITAL).
In this double-blind, placebo-controlled trial, researchers assessed the role of vitamin D3 (2000 IU daily) and/or omega-3 fatty acids (1 g daily) supplements in reducing the risks for cancer and cardiovascular disease. A total of 25,874 men (aged at least 50 years) and women (aged at least 55 years) were included in the study.
Dr LeBoff and colleagues have been tracking patients in the VITAL: Effects on Bone Structure and Architecture substudy, which includes participants from the VITAL trial. This substudy is designed to assess the effects of the interventions on bone and bone health phenotyping and clinical assessments at baseline and 2 years after randomization. The researchers have currently measured TBS in 609 participants (324 men, 285 women).
At this meeting, the investigators reported that mean TBS was greater in men than women (1.35 vs 1.32). There was also a trend associating younger age with higher TBS, Dr LeBoff said.
Additionally, TBS appeared to be lower in participants with higher BMIs and in those who used medications that have been linked to fractures.
Results also showed an association between a history of diabetes and lower TBS (1.34 vs 1.29), while higher alcohol intake was associated with higher TBS.
Interestingly, the study revealed no significant differences in TBS in terms of race/ethnicity, multivitamin use, rheumatoid arthritis history, smoking status, or caffeine intake.
“In the VITAL-Bone Health study sponsored by the [National Institute of Arthritis and Musculoskeletal Skin Diseases], TBS measures showed that baseline higher TBS values are associated with clinical variables including male sex, BMI less than 30, higher MET-hours/week (physical activity), and absence of diabetes or medication use linked to fractures,” Dr LeBoff told Endocrinology Advisor. “Our 2-year post-randomization studies will help clarify the effects of moderately high-dose, daily supplemental vitamin D/and or omega-3 fatty acids on TBS and other bone health.”
She said taking a closer look at TBS and how best to use it clinically is key in helping better diagnose and manage older adults at high risk for osteoporosis and fractures. It is not only a quality-of-life issue but also a major healthcare cost issue, according to Dr LeBoff.
“Osteoporosis is a major public health problem that affects 1 out of 2 women and 1 out of 4 men in the U.S. aged 50 and over. Bone density testing using DXA is associated with fracture risk, but risk factors and bone microarchitecture also contribute to skeletal fragility,” she explained.
- Ross A. Abstract SA0262: VITamin D and OmegA-3 TriaL (VITAL) bone health study: Clinical factors associated with Trabecular Bone Score in women and men. Presented at: American Society for Bone and Mineral Research (ASBMR) 2015 Annual Meeting; Oct. 9-12, 2015; Seattle.