Tay, Yu-Kwang Donovan; Cusano, Natalie E.; Rubin, Mishaela R.; Williams, John; Omeragic, Beatriz; Bilezikian, John P.
ContextObesity has been shown to be unfavorable to skeletal microarchitecture when assessed by trabecular bone score (TBS). The influence of adiposity on skeletal microstructure in primary hyperparathyroidism (PHPT) has not yet been evaluated.ObjectiveTo investigate the effect of obesity on TBS and bone mineral density (BMD) in subjects with PHPT at baseline and through 2 years after parathyroidectomy.DesignProspective observational studySettingReferral centerPatients or Other Participants30 men and women with PHPT undergoing parathyroid surgeryMain Outcome MeasuresTBS and BMD by dual-energy X-ray absorptiometryResultsThere were significant improvements in lumbar spine and femoral neck BMD in the obese (lumbar spine: +4.3 ± 4.7%, femoral neck: +3.8 ± 6.6%, p<,0.05 for both) and non-obese subjects (lumbar spine: +3.8 ± 5.6, femoral neck +3.1 ± 5.0%, p<,0.05 for both) but no significant change in TBS in either group at 24 months post-parathyroidectomy. Obese subjects had fully degraded TBS values compared to the non-obese subjects, whose TBS values were minimally below normal throughout the study (Baseline: 1.199 ± 0.086 vs 1.327 ± 0.099, respectively, p=0.003, 24 months: 1.181 ± 0.061 vs 1.352 ± 0.114, respectively, p=0.001), despite improvements in BMD.ConclusionsThe detrimental effect of obesity on TBS, an index of bone quality, was demonstrated in subjects with PHPT. Obesity was associated with fully degraded skeletal microarchitecture as measured by TBS in PHPT, despite similar values in bone density by DXA compared to non-obese subjects. TBS values did not improve post-parathyroidectomy in either obese or non-obese subjects.