Endocrine Abstracts

Background: In asthmatic patients, in addition to conventional risk factors for osteoporosis, inflammatory factors and treatment with corticosteroids may also lead them to further bone loss. The trabecular bone score (TBS) is a new indirect parameter of bone quality. There has been no study which evaluates TBS in asthmatic patients according to use of corticosteroids.

Objective: This study evaluated the TBS according to the severity of asthma and the correlation of TBS with steroid dose and the severity of asthma in patients with asthma.

Methods: This study had a cross-sectional design. Six hundred twenty-seven patients with asthma and the same number of non-asthmatic controls matched for gender and age were included in this study. The TBS was calculated in the lumbar region, based on two dimensional (2D) projections of dual-energy X-ray absorptiometry (DXA) assessments.

Results: Patients with severe active asthma exhibited a lower vertebral TBS than those with non-severe asthma, non-active asthma, and non-asthmatic subjects, whereas there were no significant differences in bone mineral density (BMD) among the study groups. TBS was significantly associated with the cumulative systemic steroid dose and high inhaled corticosteroids (ICSs) exposure over 3000 mg during previous 1 year, even after adjusting for confounding factors. TBS was also significantly correlated with FEV1/FVC and methacholine PC 20 suggesting that airway inflammation.

Conclusion: Severe active asthma patients exhibited a lower vertebral TBS regardless of age groups. TBS was significantly associated with the cumulative systemic steroid dose and high ICS exposure over 3000 mg of fluticasone equivalent dose, which was not correlated with BMD. TBS can be used for an early detector of the alterations in bone quality which are a consequence of glucocorticoid therapy or possibly the exacerbation of asthma.