Trabecular bone score norms in Asian‐Indians and associations with serum 25(OH)D and parathyroid hormone 

Abstract

ObjectiveThere is limited information on population‐specific norms of trabecular‐bone‐score (TBS) and its associated factors. Here, we provide norms of TBS in Asian‐Indians and its relationship with serum 25‐hydroxyvitamin D [25(OH)D] and intact‐parathyroid hormone (iPTH).Participants and MeasurementsTBS, bone‐mineral‐density (BMD), and vertebral‐fractures (VFs) were assessed using dual‐energy X‐ray absorptiometry in 923 healthy Asian‐Indians (aged 20–60 years). Serum 25(OH)D, iPTH, T4/TSH,, glycosylated‐haemoglobin (HbA1c) were measured and associations with TBS assessed using multivariable linear regression. Subjects with BMD Z‐score ≤ −2.0 or ≥2.0 at any sites, VFs, TSH > 10.0 or <0.05 µIU/ml, blood‐glucose >11.1 mmol/L or HbA1c > 8.0% were excluded for generating Asian‐Indian norms.ResultsTBS norms were generated in 744 healthy Asian‐Indians (M:F,389:385). The cut‐offs generated for ‘normal’, ‘partially‐degraded’, and ‘degraded’ TBS were >1.305, 1.204–1.305 and <1.204, respectively. Mean TBS was lower in females than males (p < .001). There was 75% congruency in TBS categories between Asian‐Indian and existing norms. Specificity (97.8 vs. 77.9%, p < .001) and diagnostic‐accuracy (97.8% vs. 78.4%, p < .001) of TBS to detect osteoporosis were higher with Asian‐Indian norms. The sensitivity of ‘partially‐degraded’ TBS to diagnose osteopenia was also higher with Asian‐Indian norms. In multivariable regression, gender, body‐mass‐index (BMI), BMD‐L1‐L4, serum PTH, daily dietary‐calorie intake and calcium intake were associated with TBS. Though 25(OH)D inversely correlated with PTH, 25(OH)D was not associated with TBS.ConclusionThis study provides norms for TBS in Asian‐Indians with gender‐specific differences. Increasing age and higher BMI were associated with lower TBS. Associations of TBS with circulating PTH and/or 25(OH)D need confirmation in further studies.