Effect of soft tissue noise on trabecular bone score in postmenopausal women with diabetes: A cross sectional study

Background: Type 2 diabetes (T2D) is associated with increased fracture risk, despite similar or greater BMD compared to nondiabetics. TBS predicts fracture risk in T2D and nondiabetics. However, increased abdominal thickness, a common feature in T2D, may reduce TBS values. Aim: To study the relationship among glycemic status, BMD and TBS, considering abdominal soft tissue thickness (STT) interference. Methods: Cross-sectional analysis of 493 women >= 65 years, with simultaneous DXA scans and HbAlc measures. STT and TBS (iNsight Software, v3.0) were derived from lumbar spine (LS) scans. Subjects were divided according to HbAlc levels: 1 (>= 6.5%; n = 116), 2 (5.7-6.4%; n = 217) and 3 (<= 5.6%; n = 160). Group 1 was further divided based on HbAlc and/or disease duration: la (HbA1c >= 7.5%; n = 42), lb (HbA1c >= 6.5% and disease duration >= 5 years; n = 63) and 1c (HbA1c >= 7.5% and disease duration >= 5 years; n = 30). Findings: For the entire cohort, mean age, TBS, BMI and STT were 71.8 +/- 6.0 years, 1.299 +/- 0.101, 26.9 +/- 4.1 kg/m(2), and 21.4 +/- 2.9 cm, respectively. LS-BMD was similar among groups. BMD in hip sites and STT were higher in group 1. TBS was lower in patients with higher HbAlc (P = 0.020), with a mean TBS in groups 1, 2, and 3 of 1.280, 1.299 and 1.314, respectively. This difference remained after adjusting for age, LS-BMD and BMI (P = 0.010). After replacing BMI with STT, TBS differences were no longer significant (P = 0.270). The same was observed when subgroups la and 1b were compared to group 3. However, for subgroup 1c, TBS remained lower compared to group 3, even after adjusting for age, LS-BMD and STT, with a borderline P-value (1.275 vs. 1.308; P = 0.047). Conclusion: Higher HbA1c levels were associated with greater BMD in hip sites, higher abdominal SIT and lower TBS values. However, after including the STT in the adjustment, TBS differences among groups disappeared, except in women with higher HbA1c levels and longer disease duration.

Automated summary

This study investigates the relationship between glycemic status, bone mineral density (BMD), and trabecular bone score (TBS) in older women. The results show that higher HbA1c levels are associated with higher BMD in the hip sites and increased abdominal soft tissue thickness, while lower TBS values are observed. However, after adjusting for abdominal fat, the differences in TBS disappear, except in women with higher HbA1c levels and longer disease duration.