Mild Hyponatremia Is Not Associated With Degradation of Trabecular Bone Microarchitecture Despite Bone Mass Loss

Abstract

Context: Hyponatremia is associated with increased risk of osteoporosis and fractures. The impact of hyponatremia on noninvasive indices of bone quality, however, is unknown. Objective: To evaluate whether trabecular bone microarchitecture, assessed noninvasively by trabecular bone score (TBS), is altered in patients with hyponatremia. Methods: We conducted a cross-sectional analysis of the population-based 2005-2008 cycles of the National Health and Nutrition Examination Survey, in which TBS measurement was performed. The main outcome measures were TBS values and bone mineral density (BMD) T-scores at the lumbar spine, total hip and femoral neck. Results: A total of 4204 subjects aged 50 years or older were included (4041 normonatremic, 163 hyponatremic - 90.8% with mild hyponatremia). Univariate analyses did not show any difference in TBS between patients with and without hyponatremia (1.308 ± 0.145 vs 1.311 ± 0.141, P =. 806). Hyponatremic subjects had lower BMD T-score at total hip (-0.70 ± 1.46 vs -0.13 ± 1.32, P