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Trudzinski FC, Jörres RA, Alter P, Watz H, Vogelmeier CF, Kauczor HU, Thangamani S, Debic M, Welte T, Behr J, Kahnert K, Bals R, Herr C, Heußel CP, Biederer J, von Stackelberg O, Fähndrich S, Wouters EFM, Waschki B, Rabe KF, Herth FJF, Palm V. Midregional Proatrial Natriuretic Peptide (MRproANP) is associated with vertebral fractures and low bone density in patients with chronic obstructive pulmonary disease (COPD). Respir Res 2024; 25:274. [PMID: 39003487 PMCID: PMC11245771 DOI: 10.1186/s12931-024-02902-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Accepted: 07/02/2024] [Indexed: 07/15/2024] Open
Abstract
BACKGROUND Patients with COPD are often affected by loss of bone mineral density (BMD) and osteoporotic fractures. Natriuretic peptides (NP) are known as cardiac markers, but have also been linked to fragility-associated fractures in the elderly. As their functions include regulation of fluid and mineral balance, they also might affect bone metabolism, particularly in systemic disorders such as COPD. RESEARCH QUESTION We investigated the association between NP serum levels, vertebral fractures and BMD assessed by chest computed tomography (CT) in patients with COPD. METHODS Participants of the COSYCONET cohort with CT scans were included. Mean vertebral bone density on CT (BMD-CT) as a risk factor for osteoporosis was assessed at the level of TH12 (AI-Rad Companion), and vertebral compression fractures were visually quantified by two readers. Their relationship with N-terminal pro-B-type natriuretic peptide (NT-proBNP), Mid-regional pro-atrial natriuretic peptide (MRproANP) and Midregional pro-adrenomedullin (MRproADM) was determined using group comparisons and multivariable analyses. RESULTS Among 418 participants (58% male, median age 64 years, FEV1 59.6% predicted), vertebral fractures in TH12 were found in 76 patients (18.1%). Compared to patients without fractures, these had elevated serum levels (p ≤ 0.005) of MRproANP and MRproADM. Using optimal cut-off values in multiple logistic regression analyses, MRproANP levels ≥ 65 nmol/l (OR 2.34; p = 0.011) and age (p = 0.009) were the only significant predictors of fractures after adjustment for sex, BMI, smoking status, FEV1% predicted, SGRQ Activity score, daily physical activity, oral corticosteroids, the diagnosis of cardiac disease, and renal impairment. Correspondingly, MRproANP (p < 0.001), age (p = 0.055), SGRQ Activity score (p = 0.061) and active smoking (p = 0.025) were associated with TH12 vertebral density. INTERPRETATION MRproANP was a marker for osteoporotic vertebral fractures in our COPD patients from the COSYCONET cohort. Its association with reduced vertebral BMD on CT and its known modulating effects on fluid and ion balance are suggestive of direct effects on bone mineralization. TRIAL REGISTRATION ClinicalTrials.gov NCT01245933, Date of registration: 18 November 2010.
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Affiliation(s)
- Franziska C Trudzinski
- Department of Pneumology and Critical Care Medicine), German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Thoraxklinik University of Heidelberg, Röntgenstrasse 1, 69126, Heidelberg, Germany.
| | - Rudolf A Jörres
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, German Center for Lung Research (DZL), LMU University Hospital, Ludwig-Maximilians-University (LMU), Comprehensive Pneumology Center Munich (CPC-M), Munich, Germany
| | - Peter Alter
- Department of Medicine, Pulmonary and Critical Care Medicine, German Center for Lung Research (DZL), Philipps University of Marburg (UMR), Marburg, Germany
| | - Henrik Watz
- Pulmonary Research Institute at LungenClinic Grosshansdorf, Grosshansdorf, Germany
- Airway Research Center North (ARCN), German Center for Lung Research (DZL), Woehrendamm 80, 22927, Grosshansdorf, Germany
| | - Claus F Vogelmeier
- Department of Medicine, Pulmonary and Critical Care Medicine, German Center for Lung Research (DZL), Philipps University of Marburg (UMR), Marburg, Germany
| | - Hans-Ulrich Kauczor
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
| | - Subasini Thangamani
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
| | - Manuel Debic
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
| | - Tobias Welte
- Department of Pneumology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Jürgen Behr
- Department of Internal Medicine V, CPC Comprehensive Pneumology Center, Member of the German Center for Lung Research (DZL), University Hospital, LMU Munich, Munich, Germany
| | - Kathrin Kahnert
- Department of Internal Medicine V, CPC Comprehensive Pneumology Center, Member of the German Center for Lung Research (DZL), University Hospital, LMU Munich, Munich, Germany
- MediCenterGermering, Germering, Germany
| | - Robert Bals
- Department of Internal Medicine V - Pulmonology, Allergology, Critical Care Care Medicine, Saarland University Hospital, Homburg, Germany
| | - Christian Herr
- Department of Internal Medicine V - Pulmonology, Allergology, Critical Care Care Medicine, Saarland University Hospital, Homburg, Germany
| | - Claus Peter Heußel
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology With Nuclear Medicine, Thoraxklinik, University Medical Center Heidelberg, Heidelberg, Germany
| | - Jürgen Biederer
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
- Faculty of Medicine, University of Latvia, Riga, Latvia
- Faculty of Medicine, Christian-Albrechts-Universität Zu Kiel, Kiel, Germany
| | - Oyunbileg von Stackelberg
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
| | - Sebastian Fähndrich
- Department of Pneumology, University Medical Centre Freiburg, Freiburg, Germany
| | - Emiel F M Wouters
- Department of Respiratory Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
- Medical Faculty, Sigmund Freud University, Vienna, Austria
- Department of Internal Medicine, Sigmund Freud Private University, Vienna, Austria
| | - Benjamin Waschki
- LungenClinic Grosshansdorf, Airway Research Center North, Member of the German Center for Lung Research, Pulmonary Research Institute, Woehrendamm 80, 22927, Grosshansdorf, Germany
- Department of Pneumology, Itzehoe Hospital, Itzehoe, Germany
| | - Klaus F Rabe
- LungenClinic Grosshansdorf, Airway Research Center North, Member of the German Center for Lung Research, Pulmonary Research Institute, Woehrendamm 80, 22927, Grosshansdorf, Germany
| | - Felix J F Herth
- Department of Pneumology and Critical Care Medicine), German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Thoraxklinik University of Heidelberg, Röntgenstrasse 1, 69126, Heidelberg, Germany
| | - Viktoria Palm
- Department of Diagnostic & Interventional Radiology, University Hospital of Heidelberg, Heidelberg, Germany
- German Center for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC-H), Heidelberg, Germany
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Szulc P, Lewis JR, Chapurlat R. Accelerated Bone Loss in Older Men With Severe Abdominal Aortic Calcification-the Prospective MINOS Study. J Clin Endocrinol Metab 2023; 109:e32-e39. [PMID: 37610245 DOI: 10.1210/clinem/dgad459] [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: 06/05/2023] [Revised: 06/30/2023] [Accepted: 08/07/2023] [Indexed: 08/24/2023]
Abstract
CONTEXT Data on the association between the severity of abdominal aortic calcification (AAC) and bone loss are discordant. OBJECTIVE Our aim was to assess the association between baseline AAC and prospectively assessed bone loss in older men. METHODS This prospective cohort study started in 1995 (MINOS). Men aged 50 to 85 years (n = 778) had AAC assessed on the lateral radiograph of the spine using Kauppila's semiquantitative score and was followed prospectively for 7.5 years. Bone mineral density (BMD) and bone mineral content (BMC) were measured by dual-energy x-ray absorptiometry every 18 months. Statistical analysis was performed using linear mixed models. RESULTS In comparison to men without AAC (AAC = 0), severe AAC (>6) was associated with more rapid bone loss at the total hip (-0.62 ± 0.06 vs -0.32 ± 0.04%/year; P < .001), trochanter, and distal forearm (-0.72 ± 0.06 vs -0.45 ± 0.03%/year; P < .001). The highest decile (AAC >10) was associated with more rapid bone loss at the femoral neck, whole body, and ultradistal radius (-0.86 ± 0.12 vs -0.34 ± 0.05%/year; P < .001). The results were similar for BMD and for BMC. The patterns were similar in sensitivity analyses (eg, after excluding men with abdominal obesity, after excluding current smokers, after excluding men with ischemic heart disease or with diabetes mellitus, after excluding men with abnormal concentrations of lipids, bioavailable 17β-estradiol or 25-hydroxycholecalciferol, after excluding men with glomerular filtration rate <60 mL/min). CONCLUSION Severe AAC is associated with faster bone loss in older men and may contribute to the higher fracture risk observed in this population.
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Affiliation(s)
- Pawel Szulc
- INSERM UMR 1033, University of Lyon, Hospices Civils de Lyon, 69437, Lyon, France
| | - Joshua R Lewis
- Institute for Nutrition Research, Edith Cowan University, Joondalup, Perth, WA 6027, Australia
- Medical School, the University of Western Australia, Perth, WA 6009, Australia
| | - Roland Chapurlat
- INSERM UMR 1033, University of Lyon, Hospices Civils de Lyon, 69437, Lyon, France
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Bandeira F, de Oliveira LB, Caldeira RB, Toscano LS. Skeletal consequences of heart failure. WOMEN'S HEALTH (LONDON, ENGLAND) 2022; 18:17455057221135501. [PMID: 36321835 PMCID: PMC9634191 DOI: 10.1177/17455057221135501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/29/2022] [Accepted: 10/10/2022] [Indexed: 01/24/2023]
Abstract
Heart failure (HF) is a prevalent clinical syndrome that causes significant physical limitations. Osteoporosis is also an important cause of loss of functionality, and it mainly affects women. There are several reports linking HF and osteoporosis, and both share risk factors. Most of the data available so far point to bone fragility as a consequence of HF, and several mechanisms have been identified to explain this relationship. Among the proposed pathophysiological mechanisms are the hyperactivation of the renin-angiotensin-aldosterone system and the increase in parathyroid hormone, functional limitation, production of inflammatory mediators and the use of drugs for HF. The role of osteoprotegerin has gained attention owing to its cardiovascular and skeletal effects, its observed deficiency during the postmenopausal period along with its compensatory increases in HF and severe osteoporosis. The objective of this review was to perform a literature search for the main evidence on skeletal impairment in HF, with emphasis on women. As for epidemiological studies, we selected data from 3 meta-analyses and 20 individual observational studies, which together showed the interrelationship between the two clinical conditions in terms of both decreased bone density and increased fracture risk. In conclusion, HF and osteoporosis are interrelated conditions mediated by complex pathophysiological mechanisms which may be more relevant for postmenopausal women, considered to be a vulnerable population for both cardiovascular diseases and bone fragility.
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Affiliation(s)
- Francisco Bandeira
- Division of Endocrinology and Diabetes, Agamenon
Magalhães Hospital, Faculty of Medical Sciences, University of Pernambuco (UPE),
Recife, Brazil
| | - Lucian Batista de Oliveira
- Division of Endocrinology and Diabetes, Agamenon
Magalhães Hospital, Faculty of Medical Sciences, University of Pernambuco (UPE),
Recife, Brazil
| | - Rodrigo Botelho Caldeira
- Division of Endocrinology and Diabetes, Agamenon
Magalhães Hospital, Faculty of Medical Sciences, University of Pernambuco (UPE),
Recife, Brazil
| | - Leticia Saldanha Toscano
- Division of Endocrinology and Diabetes, Agamenon
Magalhães Hospital, Faculty of Medical Sciences, University of Pernambuco (UPE),
Recife, Brazil
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Hao Y, Chen Y. Vitamin D levels and vitamin D receptor variants are associated with chronic heart failure in Chinese patients. J Clin Lab Anal 2019; 33:e22847. [PMID: 30714636 PMCID: PMC6528604 DOI: 10.1002/jcla.22847] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 11/25/2018] [Accepted: 12/05/2018] [Indexed: 01/01/2023] Open
Abstract
Background Vitamin D is an indispensable molecule for human health. Wide ranges of diseases are linked with vitamin D deficiencies. Role of vitamin D in chronic heart failure has been demonstrated in different populations; however, reports are limited in Chinese population. Vitamin D exerts its effect through vitamin D receptor and variants in vitamin D receptor (VDR) gene are shown to affect vitamin D signaling. In the present study, we hypothesized that both vitamin D levels and VDR variants could be associated with the development of chronic heart failure. Materials and Methods We enrolled 145, chronic heart failure patients those admitted to Department of Cardiothoracic Surgery, Beijing Luhe Hospital of Capital Medical University and fulfilled NYHA inclusions criteria. In addition, ninety healthy subjects from similar geographical location were enrolled as healthy controls. Plasma levels of vitamin D were quantified by ELISA. VDR variants (BsmI, ApaI, TaqI, and FokI) were genotyped by PCR‐RFLP. Results Plasma levels of vitamin D were significantly lower in chronic heart patients compared to healthy controls. Heterozygous and minor allele for FokI and TaqI polymorphisms were significantly higher in heart failure patients when compared to healthy controls. In addition, combined analysis of vitamin D levels and VDR mutants revealed association of vitamin D deficiencies and VDR mutants with chronic heart failure. Conclusions The results of the present investigation showed an important role of vitamin D and VDR variants with chronic heart failure.
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Affiliation(s)
- Yi Hao
- Department of Cardiothoracic Surgery, Beijing Luhe Hospital of Capital Medical University, Beijing, China
| | - Yueling Chen
- Department of Cardiothoracic Surgery, Beijing Luhe Hospital of Capital Medical University, Beijing, China
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Chiu CZ, Yeh JH, Shyu KG, Hou SM, Lin CL, Liang JA. Can osteoporosis increase the incidence of heart failure in adults? Curr Med Res Opin 2017; 33:1119-1125. [PMID: 28301957 DOI: 10.1080/03007995.2017.1308343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Recent studies have suggested shared comorbidities between heart failure and osteoporosis. In addition, patients with osteoporosis are associated with increased risks of developing cardiovascular disease. METHODS A retrospective cohort analysis was conducted to determine the association between osteoporosis and heart failure. Data was from the Longitudinal Health Insurance Database 2000 (LHID 2000), Taiwan. Patients with newly diagnosed osteoporosis were identified, and osteoporosis-free controls were randomly selected from the general population and frequency matched according to age, sex, and index year using the LHID 2000. We analyzed the risks of heart failure using Cox proportional-hazards regression models. RESULTS During the mean follow-up of 7.1 ± 3.5 years, the cumulative incidence of heart failure was 2.24% higher in the osteoporosis cohort than in the comparison cohort (p < .001). The overall incidence of heart failure was 10.3 versus 7.62 per 1000 person-years in osteoporosis patients and controls, respectively, with an adjusted HR of 1.13 (95% CI = 1.06-1.21). CONCLUSION We observed a higher incidence of developing heart failure in Taiwanese adults with osteoporosis, especially in those with chronic comorbidities. There might be linking pathophysiology and mechanisms from osteoporosis to heart failure.
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Affiliation(s)
- Chiung-Zuan Chiu
- a School of Medicine , Fu-Jen Catholic University , New Taipei , Taiwan
- b Division of Cardiology , Shin-Kong Wu Ho-Su Memorial Hospital , Taipei , Taiwan
| | - Jiann-Horng Yeh
- a School of Medicine , Fu-Jen Catholic University , New Taipei , Taiwan
- c Division of Neurology , Shin-Kong Wu Ho-Su Memorial Hospital , Taipei , Taiwan
| | - Kou-Gi Shyu
- b Division of Cardiology , Shin-Kong Wu Ho-Su Memorial Hospital , Taipei , Taiwan
| | - Sheng-Mou Hou
- d Division of Orthopedics , Shin-Kong Wu Ho-Su Memorial Hospital , Taipei , Taiwan
| | - Cheng-Li Lin
- e Management Office for Health Data, China Medical University Hospital , Taichung , Taiwan
- f College of Medicine , China Medical University , Taichung , Taiwan
| | - Ji-An Liang
- g Department of Radiation Oncology , China Medical University Hospital , Taichung , Taiwan
- h Graduate Institute of Clinical Medical Science and School of Medicine, College of Medicine , China Medical University , Taichung , Taiwan
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Caudarella R, Vescini F, Rizzoli E, Ulivieri FM. The Effect of Thiazides on Bone Markers, Bone Mineral Density and Fractures. Clin Rev Bone Miner Metab 2015. [DOI: 10.1007/s12018-015-9190-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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8
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Ghosh M, Majumdar SR. Antihypertensive medications, bone mineral density, and fractures: a review of old cardiac drugs that provides new insights into osteoporosis. Endocrine 2014; 46:397-405. [PMID: 24504763 DOI: 10.1007/s12020-014-0167-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 01/04/2014] [Indexed: 01/20/2023]
Abstract
Osteoporosis is increasing in prevalence and importance as society's age, with the clinical consequence of fractures of the hip, spine, and upper extremity, leading to impaired quality of life, loss of function and independence, and increased morbidity and mortality. A major risk factor for osteoporosis is older age, and cardiovascular diseases also share this risk factor; therefore, osteoporosis and cardiovascular disease often coexist and share risk factors. Medications used for the treatment of cardiovascular diseases, in particular antihypertensive drugs, have been shown in a variety of studies of varying designs to modulate bone health in both a positive or negative manner. In this article, we reviewed the pharmacology, potential mechanisms, and possible effects on bone mineral density and fracture risk of commonly prescribed antihypertensive medications, including thiazide and non-thiazide diuretics, beta-blockers, calcium channel blockers, renin-angiotensin-aldosterone system agents, and nitrates.
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Affiliation(s)
- Mahua Ghosh
- Division of General Internal Medicine, Department of Medicine, University of Alberta, Edmonton, AB, Canada
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Abstract
The symptoms and signs constituting the congestive heart failure (CHF) syndrome have their pathophysiologic origins rooted in a salt-avid renal state mediated by effector hormones of the renin-angiotensin-aldosterone and adrenergic nervous systems. Controlled clinical trials, conducted over the past decade in patients having minimally to markedly severe symptomatic heart failure, have demonstrated the efficacy of a pharmacologic regimen that interferes with these hormones, including aldosterone receptor binding with either spironolactone or eplerenone. Potential pathophysiologic mechanisms, which have not hitherto been considered involved for the salutary responses and cardioprotection provided by these mineralocorticoid receptor antagonists, are reviewed herein. In particular, we focus on the less well-recognized impact of catecholamines and aldosterone on monovalent and divalent cation dyshomeostasis, which leads to hypokalemia, hypomagnesemia, ionized hypocalcemia with secondary hyperparathyroidism and hypozincemia. Attendant adverse cardiac consequences include a delay in myocardial repolarization with increased propensity for supraventricular and ventricular arrhythmias, and compromised antioxidant defenses with increased susceptibility to nonischemic cardiomyocyte necrosis.
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Aluoch AO, Jessee R, Habal H, Garcia-Rosell M, Shah R, Reed G, Carbone L. Heart failure as a risk factor for osteoporosis and fractures. Curr Osteoporos Rep 2012; 10:258-69. [PMID: 22915207 DOI: 10.1007/s11914-012-0115-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Although heart failure (HF) and osteoporosis are common diseases, particularly in elderly populations, patients with HF have an increased risk for osteoporosis. The relationship of HF with osteoporosis is modified by gender and the severity of HF. In addition, shared risk factors, medication use, and common pathogenic mechanisms affect both HF and osteoporosis. Shared risk factors for these 2 conditions include advanced age, hypovitaminosis D, renal disease, and diabetes mellitus. Medications used to treat HF, including spironolactone, thiazide diuretics, nitric oxide donors, and aspirin, may protect against osteoporosis. In contrast, loop diuretics may make osteoporosis worse. HF and osteoporosis appear to share common pathogenic mechanisms, including activation of the renin-angiotensin-aldosterone system, increased parathyroid hormone levels, and/or oxidative/nitrosative stress. HF is a major risk factor for mortality following fractures. Thus, in HF patients, it is important to carefully assess osteoporosis and take measures to reduce the risk of osteoporotic fractures.
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Affiliation(s)
- Aloice O Aluoch
- Department of Medicine, University of TN Health Science Center, Memphis, 38163, USA
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Yusuf J, Khan MU, Cheema Y, Bhattacharya SK, Weber KT. Disturbances in calcium metabolism and cardiomyocyte necrosis: the role of calcitropic hormones. Prog Cardiovasc Dis 2012; 55:77-86. [PMID: 22824113 DOI: 10.1016/j.pcad.2012.02.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A synchronized dyshomeostasis of extra- and intracellular Ca(2+), expressed as plasma ionized hypocalcemia and excessive intracellular Ca(2+) accumulation, respectively, represents a common pathophysiologic scenario that accompanies several diverse disorders. These include low-renin and salt-sensitive hypertension, primary aldosteronism and hyperparathyroidism, congestive heart failure, acute and chronic hyperadrenergic stressor states, high dietary Na(+), and low dietary Ca(2+) with hypovitaminosis D. Homeostatic responses are invoked to restore normal extracellular [Ca(2+)](o), including increased plasma levels of parathyroid hormone and 1,25(OH)(2)D(3). However, in cardiomyocytes these calcitropic hormones concurrently promote cytosolic free [Ca(2+)](i) and mitochondrial [Ca(2+)](m) overloading. The latter sets into motion organellar-based oxidative stress, in which the rate of reactive oxygen species generation overwhelms their detoxification by endogenous antioxidant defenses, including those related to intrinsically coupled increments in intracellular Zn(2+). In turn, the opening potential of the mitochondrial permeability transition pore increases, allowing for osmotic swelling and ensuing organellar degeneration. Collectively, these pathophysiologic events represent the major components to a mitochondriocentric signal-transducer-effector pathway to cardiomyocyte necrosis. From necrotic cells, there follows a spillage of intracellular contents, including troponins, and a subsequent wound healing response with reparative fibrosis or scarring. Taken together, the loss of terminally differentiated cardiomyocytes from this postmitotic organ and the ensuing replacement fibrosis each contribute to the adverse structural remodeling of myocardium and progressive nature of heart failure. In conclusion, hormone-induced ionized hypocalcemia and intracellular Ca(2+) overloading comprise a pathophysiologic cascade common to diverse disorders and that initiates a mitochondriocentric pathway to nonischemic cardiomyocyte necrosis.
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Affiliation(s)
- Jawwad Yusuf
- Division of Cardiovascular Diseases, Department of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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Parathyroid Hormone, A Crucial Mediator of Pathologic Cardiac Remodeling in Aldosteronism. Cardiovasc Drugs Ther 2012; 27:161-70. [DOI: 10.1007/s10557-012-6378-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Weber KT, Bhattacharya SK, Newman KP, Soberman JE, Ramanathan KB, McGee JE, Malik KU, Hickerson WL. Stressor states and the cation crossroads. J Am Coll Nutr 2011; 29:563-74. [PMID: 21677120 DOI: 10.1080/07315724.2010.10719895] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Neurohormonal activation involving the hypothalamic-pituitary-adrenal axis and adrenergic nervous and renin-angiotensin-aldosterone systems is integral to stressor state-mediated homeostatic responses. The levels of effector hormones, depending upon the degree of stress, orchestrate the concordant appearance of hypokalemia, ionized hypocalcemia and hypomagnesemia, hypozincemia, and hyposelenemia. Seemingly contradictory to homeostatic responses wherein the constancy of extracellular fluid would be preserved, upregulation of cognate-binding proteins promotes coordinated translocation of cations to injured tissues, where they participate in wound healing. Associated catecholamine-mediated intracellular cation shifts regulate the equilibrium between pro-oxidants and antioxidant defenses, a critical determinant of cell survival. These acute and chronic stressor-induced iterations in extracellular and intracellular cations are collectively referred to as the cation crossroads. Intracellular cation shifts, particularly excessive accumulation of Ca2+, converge on mitochondria to induce oxidative stress and raise the opening potential of their inner membrane permeability transition pores (mPTPs). The ensuing loss of cationic homeostasis and adenosine triphosphate (ATP) production, together with osmotic swelling, leads to organellar degeneration and cellular necrosis. The overall impact of iterations in extracellular and intracellular cations and their influence on cardiac redox state, cardiomyocyte survival, and myocardial structure and function are addressed herein.
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Affiliation(s)
- Karl T Weber
- Division of Cardiovascular Diseases, University of Tennessee Health Science Center, 956 Court Ave., Suite A312, Memphis, TN 38163, USA.
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Oxidative Stress and Cardiomyocyte Necrosis With Elevated Serum Troponins: Pathophysiologic Mechanisms. Am J Med Sci 2011; 342:129-34. [DOI: 10.1097/maj.0b013e3182231ee3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Borkowski BJ, Cheema Y, Shahbaz AU, Bhattacharya SK, Weber KT. Cation dyshomeostasis and cardiomyocyte necrosis: the Fleckenstein hypothesis revisited. Eur Heart J 2011; 32:1846-53. [PMID: 21398641 DOI: 10.1093/eurheartj/ehr063] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
An ongoing loss of cardiomyocytes to apoptotic and necrotic cell death pathways contributes to the progressive nature of heart failure. The pathophysiological origins of necrotic cell loss relate to the neurohormonal activation that accompanies acute and chronic stressor states and which includes effector hormones of the adrenergic nervous system. Fifty years ago, Albrecht Fleckenstein and coworkers hypothesized the hyperadrenergic state, which accompanies such stressors, causes cardiomyocyte necrosis based on catecholamine-initiated excessive intracellular Ca(2+) accumulation (EICA), and mitochondrial Ca(2+) overloading in particular, in which the ensuing dysfunction and structural degeneration of these organelles leads to necrosis. In recent years, two downstream factors have been identified which, together with EICA, constitute a signal-transducer-effector pathway: (i) mitochondria-based induction of oxidative stress, in which the rate of reactive oxygen metabolite generation exceeds their rate of detoxification by endogenous antioxidant defences; and (ii) the opening of the mitochondrial inner membrane permeability transition pore (mPTP) followed by organellar swelling and degeneration. The pathogenesis of stress-related cardiomyopathy syndromes is likely related to this pathway. Other factors which can account for cytotoxicity in stressor states include: hypokalaemia; ionized hypocalcaemia and hypomagnesaemia with resultant elevations in parathyroid hormone serving as a potent mediator of EICA; and hypozincaemia with hyposelenaemia, which compromise antioxidant defences. Herein, we revisit the Fleckenstein hypothesis of EICA in leading to cardiomyocyte necrosis and the central role played by mitochondria.
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Affiliation(s)
- Brian J Borkowski
- Division of Cardiovascular Diseases, University of Tennessee Health Science Center, 956 Court Ave., Suite A312, Memphis, TN 38162, USA
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Carbone LD, Cross JD, Raza SH, Bush AJ, Sepanski RJ, Dhawan S, Khan BQ, Gupta M, Ahmad K, Khouzam RN, Dishmon DA, Nesheiwat JP, Hajjar MA, Chishti WA, Nasser W, Khan M, Womack CR, Cho T, Haskin AR, Weber KT. Fracture risk in men with congestive heart failure risk reduction with spironolactone. J Am Coll Cardiol 2008; 52:135-8. [PMID: 18598893 DOI: 10.1016/j.jacc.2008.03.039] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 02/15/2008] [Accepted: 03/04/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVES The purpose of this study was to determine whether spironolactone use is associated with fractures in men with congestive heart failure (CHF). BACKGROUND In rats with aldosteronism, spironolactone preserves skeletal strength. However, in humans, the relationship of spironolactone to fractures is not known. METHODS The medical records of all male patients with CHF from 1999 to 2005 treated at the Veterans Affairs Medical Center, Memphis, Tennessee, were reviewed (n = 4,735). Odds ratios with 95% confidence intervals of having a fracture associated with spironolactone use were estimated using conditional logistic regression. RESULTS We identified 167 cases with a single-incident fracture and matched these by age and race to 668 control subjects without fractures. After adjustment for covariates, spironolactone use was inversely associated with total fracture (odds ratio: 0.575; 95% confidence interval: 0.346 to 0.955, p = 0.0324). CONCLUSIONS The use of spironolactone is inversely associated with fractures in men with CHF.
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Affiliation(s)
- Laura D Carbone
- Department of Veterans Affairs Medical Center, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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17
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Laudisio A, Marzetti E, Antonica L, Cocchi A, Bernabei R, Zuccalà G. Association of left ventricular function with bone mineral density in older women: a population-based study. Calcif Tissue Int 2008; 82:27-33. [PMID: 18175031 DOI: 10.1007/s00223-007-9094-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Accepted: 11/24/2007] [Indexed: 11/24/2022]
Abstract
Due to the increasing mortality and disability rates associated with hip and vertebral fractures in older age, research is currently focusing on "new" determinants of osteoporosis in elderly subjects. Most recently, low bone mineral density (BMD) has been repeatedly reported in patients with end-stage heart failure. We assessed the association, if any, of BMD with left ventricular ejection fraction (LVEF) in a general older population. We assessed the association of LVEF with T score, Z score, and stiffness index in all 312 subjects aged 75 and over living in Tuscania, Italy. Among women, LVEF was associated with T score (beta = 0.02, 95% CI 0.01-0.05; P = 0.033), Z score (beta = 0.02, 95% CI 0.01-0.04; P = 0.038), and stiffness index (beta = 0.25, 95% CI 0.02-0.48; P = 0.036) in multivariable linear regression analysis, after adjusting for lifestyle habits, demographic variables, comorbid conditions, polypharmacy, and objective measurements. No significant associations were observed in men. In linear discriminant analysis, the LVEF cutoff level that best predicted osteoporosis was < or =49%. Left ventricular function is directly and independently associated with all of the ultrasonographic BMD parameters in older women. As left ventricular dysfunction, often asymptomatic, is a prevalent finding in older women, this association and its potential therapeutic implications should be assessed in dedicated studies.
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Affiliation(s)
- Alice Laudisio
- Department of Gerontology and Geriatrics, Catholic University of Medicine, L.go F. Vito, 1-00168, Rome, Italy.
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18
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Schleithoff SS, Zittermann A, Tenderich G, Berthold HK, Stehle P, Koerfer R. Combined calcium and vitamin D supplementation is not superior to calcium supplementation alone in improving disturbed bone metabolism in patients with congestive heart failure. Eur J Clin Nutr 2007; 62:1388-94. [PMID: 17684525 DOI: 10.1038/sj.ejcn.1602861] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES To clarify the potential role of vitamin D supplementation on bone metabolism in congestive heart failure (CHF) patients with low vitamin D status and insufficient dietary calcium intake. SUBJECTS/METHODS One hundred and two ambulatory male CHF patients were recruited, of whom the majority was treated with loop diuretics. Nine patients died during follow-up. Additional 14 participants dropped out prematurely because their health status worsened markedly. Five patients had to be excluded due to lack of compliance. A daily vitamin D3 supplement plus 500 mg calcium (CaD group) or a placebo plus 500 mg calcium (Ca group) was given for 9 months. Biochemical parameters of vitamin D and bone metabolism were analyzed at baseline and after 9 months. RESULTS Median 25-hydroxyvitamin D concentrations increased from 41.7 to 103.0 nmol/l (P < 0.001) in the CaD group and remained constant in the Ca group, while median calcium intake increased above 1200 mg/day in both groups. The percentage of patients with elevated parathyroid hormone levels (> 60 pg/ml), as well as the serum concentration of undercarboxylated osteocalcin, an indicator of osteoporotic fracture risk and the bone resorption marker C-telopeptide fell significantly in both study groups (P < 0.025-0.001). At the end of the study period, biomarkers of bone turnover did not differ between groups. CONCLUSIONS A vitamin D3 supplement of 50 microg/day has no additional beneficial effects on markers of bone metabolism in CHF patients with low initial 25-hydroxyvitamin D concentrations if an adequate daily calcium intake is guaranteed.
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Affiliation(s)
- S S Schleithoff
- Institute of Nutrition and Food Sciences, University of Bonn, Germany
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19
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Zittermann A, Schleithoff SS, Koerfer R. Vitamin D insufficiency in congestive heart failure: why and what to do about it? Heart Fail Rev 2006; 11:25-33. [PMID: 16819575 DOI: 10.1007/s10741-006-9190-8] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This article gives an overview of the current knowledge on vitamin D status in patients with congestive heart failure (CHF). A serum 25-hydroxyvitamin D level below 50 nmol/l (20 ng/ml) is generally regarded as insufficient. Available data indicate that the majority of CHF patients have 25-hydroxyvitamin D levels in the insufficiency range. Skin synthesis of vitamin D after solar ultraviolet B exposure is the most important vitamin D source for humans. However, CHF patients have relatively low outdoor activities. Consequently, a disease-related sedentary lifestyle is an important cause for the insufficient vitamin D status in CHF patients. There is also evidence from a recently performed case-controlled study that indicators of ultraviolet B exposure are already reduced in CHF patients during childhood, adolescence, and early adulthood compared to healthy controls. We present results indicating that an insufficient vitamin D status may contribute to the etiology/pathogenesis of CHF. Data include a vitamin D-mediated reduction of elevated blood pressure as well as a vitamin D-mediated prevention of enhanced parathyroid hormone levels, a pathophysiological state that contributes to cardiovascular disease. Based on population attributable risks, hypertension and cardiovascular disease have a high impact, accounting for the majority of CHF events.Theoretically, vitamin D status can be improved by adequate skin synthesis of vitamin D and/or adequate oral vitamin D intake. At present, daily oral intake of 50-100 microg vitamin D seems to be the most effective way to improve vitamin D status in CHF patients.
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Affiliation(s)
- Armin Zittermann
- Klinik für Thorax- und Kardiovaskularchirurgie, Herzzentrum Nordrhein-Westfalen, Ruhr Universität Bochum, Bad Oeynhausen, Germany
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20
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Kubota T, Namba N, Kurotobi S, Kogaki S, Hirai H, Kitaoka T, Nakajima S, Ozono K. Beneficial Effect of Oral Bisphosphonate Treatment on Bone Loss Induced by Chronic Administration of Furosemide without Alteration of Its Administration and Urinary Calcium Loss. Clin Pediatr Endocrinol 2006; 15:101-7. [PMID: 24790329 PMCID: PMC4004841 DOI: 10.1297/cpe.15.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2006] [Accepted: 04/25/2006] [Indexed: 11/29/2022] Open
Abstract
Bisphosphonate is widely used to treat patients with primary and secondary osteoporosis.
The chronic administration of furosemide is considered a risk factor for osteoporosis
mainly due to the increased urinary excretion of calcium, leading to a long-term negative
balance of calcium. We describe two patients with mild heart failure who took furosemide
for more than 5 yr and developed hyperparathyroidism and lumbago associated with low bone
mineral density. Their serum levels of intact parathyroid hormone and bone mineral density
(BMD) of the lumbar spine (L2-L4) were 180.8 and 144.3 pg/ml, and 71% and 80% of the mean
of healthy women, respectively. The oral administration of alendronate or risedronate was
effective for lumbago and improved BMD, although the urinary excretion of calcium and
hyperparathyroidism were not changed. For the medical treatment of lumbago and decreased
bone mass secondary to the long-term administration of furosemide, bisphosphonate is
proposed when the dose of furosemide cannot be reduced. However, it may be important to
give sufficient calcium and vitamin D to patients to improve secondary
hyperparathyroidism.
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Affiliation(s)
- Takuo Kubota
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Noriyuki Namba
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan ; The First Department of Oral and Maxillofacial Surgery, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - Shunji Kurotobi
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shigetoyo Kogaki
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Haruhiko Hirai
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Taichi Kitaoka
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shigeo Nakajima
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
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Zittermann A, Schleithoff SS, Koerfer R. Markers of bone metabolism in congestive heart failure. Clin Chim Acta 2006; 366:27-36. [PMID: 16313895 DOI: 10.1016/j.cca.2005.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Revised: 10/20/2005] [Accepted: 10/20/2005] [Indexed: 01/06/2023]
Abstract
Congestive heart failure (CHF) is a chronic disease, whose incidence is especially growing in the subpopulation of elderly people. CHF is characterized by dyspnea and fatigue at rest or with exertion, ankle swelling and pulmonary edema. Cardiac transplantation is the ultimate therapeutic measure in patients with end-stage CHF. Some risk factors associated with CHF such as low mobility, renal failure, and prescription of specific drugs may predispose patients to develop osteoporosis. This review article gives an overview about markers of bone metabolism in CHF patients as well as in heart transplant recipients. At first, the physiology of bone metabolism is summarized. Then, a short description of different bone formation and resorption markers is presented. They can be used to characterize actual bone metabolism and can be helpful to explain possible mechanisms of bone loss. Regarding pre-transplant CHF patients, available data indicate that the disturbances in bone metabolism are only subtle. Heart transplant recipients, however, are at increased risk for osteoporotic bone loss due to the use of immunosuppressive agents such as corticosteroids and calcineurin inhibitors. Preventive strategies are able to normalize bone metabolism and to attenuate the high bone loss during the first year after heart transplantation.
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Affiliation(s)
- Armin Zittermann
- Department of Cardio-Thoracic Surgery, Heart Center Northrhine Westfalia, Ruhr University of Bochum, Georgstrasse 11, 32545 Bad Oeynhausen, Germany.
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22
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Nguyen ND, Pongchaiyakul C, Center JR, Eisman JA, Nguyen TV. Abdominal fat and hip fracture risk in the elderly: the Dubbo Osteoporosis Epidemiology Study. BMC Musculoskelet Disord 2005; 6:11. [PMID: 15727686 PMCID: PMC554111 DOI: 10.1186/1471-2474-6-11] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Accepted: 02/23/2005] [Indexed: 11/10/2022] Open
Abstract
Background Fat mass, which is a major component of body weight, is directly related to bone mineral density and reduced fracture risk. It is not known whether abdominal fat is associated with hip fracture. The present study was designed to examine the association between abdominal fat and hip fracture in women and men aged 60+ years. Methods This was a nested case-control study with one fracture case being matched with two controls of the same age. In women 63 cases were matched with 126 controls, and in men 26 cases were matched with 52 controls. Hip fracture was confirmed by X-ray and personal interview. Other measurements included weight, height, body mass index (BMI), abdominal fat, and femoral neck bone density (FNBMD). Conditional logistic regression model was used to analyse data. Results The odds ratio of hip fracture risk associated with each 10% lower abdominal fat was 1.5 (95% CI, 1.1 to 2.1) in women and 1.2 (95% CI, 0.7 to 2.0) in men. However after adjusting for FNBMD or body weight, the abdominal fat-fracture association was no longer statistically significant. Similarly, body weight and BMI was each significantly associated with hip fracture risk (in women), but after taking with account the effect of FNBMD, the association become statistically non-significant. Conclusion Lower abdominal fat was associated with an increased risk of hip fracture in elderly women, but the association was not independent of FNBMD or weight. The contribution of abdominal fat to hip fracture risk is likely to be modest.
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Affiliation(s)
- Nguyen D Nguyen
- Bone and Mineral Research Program, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney, UNSW, Australia
| | - Chatlert Pongchaiyakul
- Bone and Mineral Research Program, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney, UNSW, Australia
- Division of Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine Khon Kaen University, 40002 Thailand
| | - Jacqueline R Center
- Bone and Mineral Research Program, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney, UNSW, Australia
| | - John A Eisman
- Bone and Mineral Research Program, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney, UNSW, Australia
| | - Tuan V Nguyen
- Bone and Mineral Research Program, Garvan Institute of Medical Research, St Vincent's Hospital, Sydney, UNSW, Australia
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23
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McCarty MF. Nutritional modulation of parathyroid hormone secretion may influence risk for left ventricular hypertrophy. Med Hypotheses 2005; 64:1015-21. [PMID: 15780503 DOI: 10.1016/j.mehy.2003.12.054] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Accepted: 12/13/2003] [Indexed: 01/19/2023]
Abstract
Recent studies demonstrate low serum levels of 25-hydroxyvitamin D in patients with congestive heart failure (CHF). Although this may in part reflect reduced capacity for outdoor exercise, the possibility that poor vitamin D status increases risk for left ventricular hypertrophy (LVH), and its common sequel CHF, merits consideration. In cardiomyocytes, hormones which activate protein kinase C (PKC) -- including norepinephrine, angiotensin II, and endostatin, implicated in the pathogenesis of LVH -- induce a hypertrophic response analogous to that seen in LVH. Transgenic mice overexpressing PKC-beta2 or its upstream activator Galphaq in cardiac myofibers develop a syndrome similar to LVH. Parathyroid hormone (PTH) also activates Galphaq and PKC in cardiomyocytes, and provokes the expected hypertrophic response. Both primary and secondary hyperparathyroidism are associated with high risk for LVH. Moreover, in uncomplicated essential hypertension, left ventricular mass index has been shown to correlate very tightly with serum PTH levels, independent of blood pressure. This latter finding suggests that variations of PTH within the normal range can influence induction of LVH in at-risk subjects. If so, nutritional and lifestyle measures which modulate PTH secretion may have an impact on LVH risk. PTH secretion should be down-regulated by good vitamin D status -- achieved through supplementation or regular uv exposure -- and by vegan diets moderately low in bioavailable phosphate. Although high calcium intakes can likewise suppress PTH, they also boost renin secretion, which could have a countervailing effect on risk for LVH. Whether these nutritional measures do indeed influence LVH risk could be examined in prospective studies targeting patients at high risk, such as hypertensives.
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Affiliation(s)
- Mark F McCarty
- NutriGuard Research, 1051 Hermes Avenue, Encinitas, CA 92024, USA.
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