Romosozumab Improves Trabecular Bone Score and BMD in Osteoporotic Women with Diabetes
Overview
In postmenopausal women with osteoporosis and type 2 diabetes, 12 months of romosozumab followed by 24 months of alendronate significantly improved lumbar spine areal bone mineral density (aBMD) and tissue thickness–adjusted trabecular bone score (TBSTT) compared to alendronate alone. These improvements were maintained over 36 months and were independent of abdominal fat tissue effects.
Background
Type 2 diabetes (T2D) is associated with increased fracture risk despite relatively preserved aBMD, partly due to altered bone microarchitecture and low bone turnover. Trabecular bone score (TBS), derived from lumbar spine DXA scans, is decreased in patients with diabetes and correlates with fracture risk independent of aBMD. However, TBS can be influenced by abdominal fat tissue, leading to the development of a tissue thickness–adjusted TBS algorithm (TBSTT) to better assess bone quality. Romosozumab, an osteoanabolic agent, has demonstrated efficacy in improving bone mass and reducing fractures in postmenopausal osteoporosis, but its effects in patients with T2D had not been fully evaluated prior to this analysis.
Data Highlights
Parameter
Romosozumab-to-Alendronate (n=165)
Alendronate-to-Alendronate (n=195)
LS aBMD % Change at 12 months
Significantly greater increase vs alendronate
Lower increase
TBSTT % Change at 12 months
Significantly greater increase vs alendronate
Lower increase
LS aBMD % Change at 24 and 36 months
Maintained significant gains after transition to alendronate
Lower gains with alendronate alone
TBSTT % Change at 24 and 36 months
Maintained significant gains
Lower gains
Correlation between TBSTT and LS aBMD % Changes (R2)
0.1493
0.0429
Key Findings
Romosozumab treatment for 12 months significantly increased lumbar spine aBMD compared to alendronate in women with T2D and osteoporosis.
TBSTT, a measure adjusted for tissue thickness and abdominal fat, improved significantly more with romosozumab than with alendronate.
Improvements in both aBMD and TBSTT with romosozumab were sustained after switching to alendronate and remained superior at 24 and 36 months.
TBSTT changes showed only a weak correlation with aBMD changes, indicating they provide complementary information on bone quality.
Romosozumab may enhance bone strength in T2D patients by improving bone microarchitecture beyond what is captured by aBMD alone.
Clinical Implications
Romosozumab offers a promising anabolic treatment option for postmenopausal women with osteoporosis and type 2 diabetes, addressing both bone density and microarchitectural deficits. Adjusting TBS for tissue thickness (TBSTT) allows more accurate monitoring of bone quality changes independent of abdominal fat, which is particularly relevant in diabetic populations. Incorporating romosozumab followed by alendronate may optimize fracture risk reduction in this high-risk group.
Conclusion
Romosozumab followed by alendronate significantly improves lumbar spine bone density and microarchitecture in osteoporotic women with type 2 diabetes, with benefits sustained over 3 years. These findings support its use to enhance bone strength and potentially reduce fracture risk in this population.
References
McClung et al. 2020 -- Romosozumab in Postmenopausal Women with Osteoporosis
