Citation: Journal of the Endocrine Society. 3(2):411-426, 2019 Feb 01..Journal: Journal of the Endocrine Society.Published: ; 2019ISSN: 2472-1972.Full author list: Usala RL; Fernandez SJ; Mete M; Shara NM; Verbalis JG.UI/PMID: 30746503.Subject(s): IN PROCESS -- NOT YET INDEXEDInstitution(s): MedStar Washington Hospital Center | MedStar Health Research InstituteDepartment(s): Medicine/General Internal MedicineActivity type: Journal Article.Medline article type(s): Journal ArticleOnline resources: Click here to access onlineDigital Object Identifier: https://dx.doi.org/10.1210/js.2018-00320 (Click here)ORCID: Usala, Rachel L https://orcid.org/0000-0002-3480-5996 (Click here)Abbreviated citation: J. endocr. soc.. 3(2):411-426, 2019 Feb 01.Abstract: Context: Patients with diabetes mellitus are at increased risk for bone fragility fracture secondary to multiple mechanisms. Hyperglycemia can induce true dilutional hyponatremia. Hyponatremia is associated with gait instability, osteoporosis, and increased falls and bone fractures, and studies suggest that compromised bone quality with hyponatremia may be independent of plasma osmolality. We performed a case-control study of patients with diabetes mellitus matched by median glycated hemoglobin (HbA1c) to assess whether hyponatremia was associated with increased risk of osteoporosis and/or fragility fracture.Abstract: Design: Osteoporosis (n = 823) and fragility fracture (n = 840) cases from the MedStar Health database were matched on age of first HbA1c >=6.5%, sex, race, median HbA1c over an interval from first HbA1c >=6.5% to the end of the encounter window, diabetic encounter window length, and type 1 vs type 2 diabetes mellitus with controls without osteoporosis (n = 823) and without fragility fractures (n = 840), respectively. Clinical variables, including coefficient of glucose variation and hyponatremia (defined as serum [Na<sup>+</sup>] <135 mmol/dL within 30 days of the end of the diabetic window), were included in a multivariate analysis.Abstract: Results: Multivariate conditional logistic regression models demonstrated that hyponatremia within 30 days of the outcome measure was independently associated with osteoporosis and fragility fractures (osteoporosis OR 3.09; 95% CI, 1.37 to 6.98; fracture OR, 6.41; 95% CI, 2.44 to 16.82).Abstract: Conclusions: Our analyses support the hypothesis that hyponatremia is an additional risk factor for osteoporosis and fragility fracture among patients with diabetes mellitus.