1
|
Monnerat S, Refardt J, Potasso L, Meier C, Christ-Crain M. An Increase in Plasma Sodium Levels Is Associated With an Increase in Osteoblast Function in Chronic SIAD. J Clin Endocrinol Metab 2023; 108:e1027-e1033. [PMID: 37098131 PMCID: PMC10505522 DOI: 10.1210/clinem/dgad238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 04/27/2023]
Abstract
CONTEXT Hyponatremia is associated with increased risk for osteoporosis. Preclinical studies in untreated hyponatremia suggest osteoclast upregulation, whereas a clinical study showed improved osteoblast function after hyponatremia normalization in hospitalized patients with syndrome of inappropriate antidiuresis (SIAD). OBJECTIVE This work aimed to investigate the effect of an increase in sodium on bone turnover, that is, the ratio of the osteoblast marker procollagen type 1 N-terminal propeptide (P1NP) to the osteoclast marker cross-linked C-terminal telopeptide of type 1 collagen (CTX), in outpatients with chronic SIAD. METHODS A predefined secondary analysis was conducted of the 2-month double-blind, crossover, placebo-controlled SANDx Trial (NCT03202667) performed from December 2017 to August 2021. Participants included 11 outpatients with chronic SIAD: 6 women, median age 73 years, who received a 4-week treatment with 25-mg empagliflozin or placebo. Main outcome measures included the relationship between the change in bone formation index (BFI), defined as P1NP/CTX, and the change in plasma sodium levels. RESULTS Changes in sodium were positively correlated with changes in BFI and P1NP (BFI: ρ=.55; P < .001; P1NP: ρ=.45; P = .004) but not with CTX (P = .184) and osteocalcin (P = .149). A sodium increase of 1 mmol/l was associated with an increase of 5.21 in BFI (95% CI, 1.41-9.00; P = .013) and with an increase of 1.48 µg/l in P1NP (95% CI, .26-2.62; P = .03). The effect of sodium change on bone markers was independent of the study medication empagliflozin. CONCLUSION An increase in plasma sodium levels in outpatients with chronic hyponatremia due to SIAD, even when mild, was associated with an increase in bone formation index (P1NP/CTX) triggered by an increase in P1NP, a surrogate marker of osteoblast function.
Collapse
Affiliation(s)
- Sophie Monnerat
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland
- Department of Clinical Research, University of Basel, 4056 Basel, Switzerland
| | - Julie Refardt
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland
| | - Laura Potasso
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland
| | - Christian Meier
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland
- Department of Clinical Research, University of Basel, 4056 Basel, Switzerland
| | - Mirjam Christ-Crain
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, 4031 Basel, Switzerland
- Department of Clinical Research, University of Basel, 4056 Basel, Switzerland
| |
Collapse
|
2
|
Tzoulis P, Yavropoulou MP. Association of hyponatremia with bone mineral density and fractures: a narrative review. Ther Adv Endocrinol Metab 2023; 14:20420188231197921. [PMID: 37736657 PMCID: PMC10510353 DOI: 10.1177/20420188231197921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 07/13/2023] [Indexed: 09/23/2023] Open
Abstract
Recent studies suggest a possible association of hyponatremia with osteoporosis, falls and bone fractures. The objectives of this narrative review were to further explore this association and the related pathophysiological mechanisms and to suggest a practical approach to patients with osteoporosis or chronic hyponatremia in clinical practice. We conducted an extensive PubMed search until October 2022 with the combination of the following keywords: 'hyponatremia' or 'sodium' or 'SIADH' and 'fractures' or 'bone' or 'osteoporosis', as MeSH Terms. Review of numerous observational studies confirms a significant independent association of, even mild, hyponatremia with two- to three-fold increase in the occurrence of bone fractures. Hyponatremia is a risk factor for osteoporosis with a predilection to affect the hip, while the magnitude of association depends on the severity and chronicity of hyponatremia. Chronic hyponatremia also increases the risk for falls by inducing gait instability and neurocognitive deficits. Besides the detrimental impact of hyponatremia on bone mineral density and risk of falls, it also induces changes in bone quality. Emerging evidence suggests that acute hyponatremia shifts bone turnover dynamics towards less bone formation, while hyponatremia correction increases bone formation. The key unanswered question whether treatment of hyponatremia could improve osteoporosis and lower fracture risk highlights the need for prospective studies, evaluating the impact of sodium normalization on bone metabolism and occurrence of fractures. Recommendations for clinical approach should include measurement of serum sodium in all individuals with fracture or osteoporosis. Also, hyponatremia, as an independent risk factor for fracture, should be taken into consideration when estimating the likelihood for future fragility fracture and in clinical decision-making about pharmacological therapy of osteoporosis. Until it is proven that normalization of sodium can lower fracture occurrence, correcting hyponatremia cannot be universally recommended on this basis, but should be decided on a case-by-case basis.
Collapse
Affiliation(s)
- Ploutarchos Tzoulis
- Department of Metabolism & Experimental Therapeutics, Division of Medicine, University College London Medical School, Gower Street, London, WC1E6BT, UK
| | - Maria P. Yavropoulou
- Department of Propaedeutic and Internal Medicine, Medical School of University of Athens, Endocrinology Unit, Athens, Attica, Greece
| |
Collapse
|
3
|
Warren AM, Grossmann M, Christ-Crain M, Russell N. Syndrome of Inappropriate Antidiuresis: From Pathophysiology to Management. Endocr Rev 2023; 44:819-861. [PMID: 36974717 PMCID: PMC10502587 DOI: 10.1210/endrev/bnad010] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 02/19/2023] [Accepted: 03/27/2023] [Indexed: 03/29/2023]
Abstract
Hyponatremia is the most common electrolyte disorder, affecting more than 15% of patients in the hospital. Syndrome of inappropriate antidiuresis (SIAD) is the most frequent cause of hypotonic hyponatremia, mediated by nonosmotic release of arginine vasopressin (AVP, previously known as antidiuretic hormone), which acts on the renal V2 receptors to promote water retention. There are a variety of underlying causes of SIAD, including malignancy, pulmonary pathology, and central nervous system pathology. In clinical practice, the etiology of hyponatremia is frequently multifactorial and the management approach may need to evolve during treatment of a single episode. It is therefore important to regularly reassess clinical status and biochemistry, while remaining alert to potential underlying etiological factors that may become more apparent during the course of treatment. In the absence of severe symptoms requiring urgent intervention, fluid restriction (FR) is widely endorsed as the first-line treatment for SIAD in current guidelines, but there is considerable controversy regarding second-line therapy in instances where FR is unsuccessful, which occurs in around half of cases. We review the epidemiology, pathophysiology, and differential diagnosis of SIAD, and summarize recent evidence for therapeutic options beyond FR, with a focus on tolvaptan, urea, and sodium-glucose cotransporter 2 inhibitors.
Collapse
Affiliation(s)
- Annabelle M Warren
- Department of Medicine, University of Melbourne, Victoria 3010, Australia
- Department of Endocrinology, The Austin Hospital, Victoria 3084, Australia
| | - Mathis Grossmann
- Department of Medicine, University of Melbourne, Victoria 3010, Australia
- Department of Endocrinology, The Austin Hospital, Victoria 3084, Australia
| | - Mirjam Christ-Crain
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel 4031, Switzerland
- Department of Clinical Research, University of Basel and University Hospital Basel, Basel 4031, Switzerland
| | - Nicholas Russell
- Department of Medicine, University of Melbourne, Victoria 3010, Australia
- Department of Endocrinology, The Austin Hospital, Victoria 3084, Australia
| |
Collapse
|
4
|
Busl KM, Rabinstein AA. Prevention and Correction of Dysnatremia After Aneurysmal Subarachnoid Hemorrhage. Neurocrit Care 2023; 39:70-80. [PMID: 37138158 DOI: 10.1007/s12028-023-01735-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 04/12/2023] [Indexed: 05/05/2023]
Abstract
BACKGROUND Dysnatremia occurs commonly in patients with aneurysmal subarachnoid hemorrhage (aSAH). The mechanisms for development of sodium dyshomeostasis are complex, including the cerebral salt-wasting syndrome, the syndrome of inappropriate secretion of antidiuretic hormone, diabetes insipidus. Iatrogenic occurrence of altered sodium levels plays a role, as sodium homeostasis is tightly linked to fluid and volume management. METHODS Narrative review of the literature. RESULTS Many studies have aimed to identify factors predictive of the development of dysnatremia, but data on associations between dysnatremia and demographic and clinical variables are variable. Furthermore, although a clear relationship between serum sodium serum concentrations and outcomes has not been established-poor outcomes have been associated with both hyponatremia and hypernatremia in the immediate period following aSAH and set the basis for seeking interventions to correct dysnatremia. While sodium supplementation and mineralocorticoids are frequently administered to prevent or counter natriuresis and hyponatremia, evidence to date is insufficient to gauge the effect of such treatment on outcomes. CONCLUSIONS In this article, we reviewed available data and provide a practical interpretation of these data as a complement to the newly issued guidelines for management of aSAH. Gaps in knowledge and future directions are discussed.
Collapse
Affiliation(s)
- Katharina M Busl
- Departments of Neurology and Neurosurgery, College of Medicine, University of Florida, Gainesville, FL, USA.
| | | |
Collapse
|
5
|
Huang HY, Huang ZQ, Hua LY, Liu WS, Xu F, Ge XQ, Lu CF, Su JB, Wang XQ. The association between normal serum sodium levels and bone turnover in patients with type 2 diabetes. Front Endocrinol (Lausanne) 2022; 13:927223. [PMID: 36387923 PMCID: PMC9646934 DOI: 10.3389/fendo.2022.927223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 10/17/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Sodium is a critically important component of bones, and hyponatremia has firmly been established as a risk factor associated with the incidence of fragility fractures. However, researches have also revealed that lower serum sodium are linked to reductions in muscle mass and a higher risk of cardiovascular disease even when these levels are within the normal range. Accordingly, this study was developed to examine the relationships between normal serum sodium concentrations and bone turnover in patients with type 2 diabetes (T2D). METHODS Patients with T2D were enrolled in the present study from January 2021 to April 2022. All patients underwent analyses of serum sodium levels, oral glucose tolerance testing (OGTT), bone turnover markers (BTMs), and dual-energy X-ray absorptiometry (DXA) scanning. BTMs included bone formation markers osteocalcin (OC) and N-terminal propeptide of type-I procollagen (PINP), and bone resorption marker C-terminal telopeptide (CTx). Patients were stratified into three subgroups based on the tertiles of their serum sodium concentrations. RESULTS In total, 372 patients with T2D and sodium levels in the normal range were enrolled in this study. Serum OC and PINP levels were increased from subgroup with the low sodium tertile to that with the high sodium tertile (p for trend < 0.05), whereas CTx level was comparable among the subgroups. A positive correlation was detected between serum sodium levels and both lnOC (r = 0.210, p < 0.001) and lnPINP (r = 0.196, p < 0.001), with these relationships remaining significant even following adjustment for age, sex, body mass index (BMI), and HbA1c. Only after adjusting for these four factors a positive correlation was detected between serum sodium levels and CTx levels (r = 0.108, p < 0.05). Linear regression analyses revealed that following adjustment for potential covariates, serum sodium level was and positively significantly associated with lnOC level (β = 0.134, t = 2.281, p < 0.05) and PINP level (β = 0.179, t = 3.023, p < 0.01). CONCLUSION These results highlight a significant association between low-normal serum sodium levels and low bone turnover.
Collapse
Affiliation(s)
- Hai-yan Huang
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Zhi-qi Huang
- Department of General Surgery, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Ling-yan Hua
- Department of Ophthalmology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Wang-shu Liu
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Feng Xu
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Xiao-qin Ge
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
| | - Chun-feng Lu
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
- *Correspondence: Chun-feng Lu, ; Jian-bin Su, ; Xue-qin Wang,
| | - Jian-bin Su
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
- *Correspondence: Chun-feng Lu, ; Jian-bin Su, ; Xue-qin Wang,
| | - Xue-qin Wang
- Department of Endocrinology, Affiliated Hospital 2 of Nantong University and First People’s Hospital of Nantong City, Nantong, China
- *Correspondence: Chun-feng Lu, ; Jian-bin Su, ; Xue-qin Wang,
| |
Collapse
|