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Elsheikh M, El Sabagh A, Mohamed IB, Bhongade M, Hassan MM, Jalal PK. Frailty in end-stage liver disease: Understanding pathophysiology, tools for assessment, and strategies for management. World J Gastroenterol 2023; 29:6028-6048. [PMID: 38130738 PMCID: PMC10731159 DOI: 10.3748/wjg.v29.i46.6028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/08/2023] [Accepted: 12/01/2023] [Indexed: 12/13/2023] Open
Abstract
Frailty and sarcopenia are frequently observed in patients with end-stage liver disease. Frailty is a complex condition that arises from deteriorations across various physiological systems, including the musculoskeletal, cardiovascular, and immune systems, resulting in a reduced ability of the body to withstand stressors. This condition is associated with declined resilience and increased vulnerability to negative outcomes, including disability, hospitalization, and mortality. In cirrhotic patients, frailty is influenced by multiple factors, such as hyperammonemia, hormonal imbalance, malnutrition, ascites, hepatic encephalopathy, and alcohol intake. Assessing frailty is crucial in predicting morbidity and mortality in cirrhotic patients. It can aid in making critical decisions regarding patients' eligibility for critical care and transplantation. This, in turn, can guide the development of an individualized treatment plan for each patient with cirrhosis, with a focus on prioritizing exercise, proper nutrition, and appropriate treatment of hepatic complications as the primary lines of treatment. In this review, we aim to explore the topic of frailty in liver diseases, with a particular emphasis on pathophysiology, clinical assessment, and discuss strategies for preventing frailty through effective treatment of hepatic complications. Furthermore, we explore novel assessment and management strategies that have emerged in recent years, including the use of wearable technology and telemedicine.
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Affiliation(s)
- Mazen Elsheikh
- Department of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX 77030, United States
| | - Ahmed El Sabagh
- Department of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX 77030, United States
| | - Islam B Mohamed
- Department of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX 77030, United States
| | - Megha Bhongade
- Department of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX 77030, United States
| | - Manal M Hassan
- Department of Epidemiology, Division of Cancer Prevention and Population Sciences, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, United States
| | - Prasun Kumar Jalal
- Department of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX 77030, United States
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Warner II ER, Satapathy SK. Sarcopenia in the Cirrhotic Patient: Current Knowledge and Future Directions. J Clin Exp Hepatol 2023; 13:162-177. [PMID: 36647414 PMCID: PMC9840086 DOI: 10.1016/j.jceh.2022.06.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 06/13/2022] [Indexed: 02/07/2023] Open
Abstract
Cirrhosis predisposes to abnormalities in energy, hormonal, and immunological homeostasis. Disturbances in these metabolic processes create susceptibility to sarcopenia or pathological muscle wasting. Sarcopenia is prevalent in cirrhosis and its presence portends significant adverse outcomes including the length of hospital stay, infectious complications, and mortality. This highlights the importance of identification of at-risk individuals with early nutritional, therapeutic and physical therapy intervention. This manuscript summarizes literature relevant to sarcopenia in cirrhosis, describes current knowledge, and elucidates possible future directions.
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Key Words
- ACE, angiotensin-converting enzyme
- ACE-I, angiotensin-converting enzyme inhibitor
- AKI, acute kidney injury
- ALM, appendicular lean mass
- ARB, angiotensin receptor blocker
- ASM, appendicular skeletal mass
- AT1R, angiotensin type 1 receptor
- AT2R, angiotensin type 2 receptor
- ATP, adenosine-5′-triphosphate
- AWGS, Asian Working Group for Sarcopenia
- BCAA, branched chained amino acids
- BIA, bioelectrical impedance analysis
- BMI, body mass index
- CART, classification and regression tree
- CKD, chronic kidney disease
- CRP, C-reactive protein
- DEXA, dual energy X-ray absorptiometry
- EAA, essential amino acids
- ESPEN-SIG, European Society for Clinical Nutrition and Metabolism Special Interests Groups
- ESRD, end-stage renal disease
- EWGSOP, European Working Group on Sarcopenia in Older People
- FAD, flavin adenine dinucleotide
- FADH2, flavin adenine dinucleotide +2 hydrogen
- FNIH, Foundation for the National Institutes of Health
- GTP, guanosine-5′-triphosphate
- GnRH, gonadotrophin-releasing hormone
- HCC, hepatocellular carcinoma
- HPT, hypothalamic-pituitary-testicular
- IFN-γ, interferon γ
- IGF-1, insulin-like growth factor 1
- IL-1, interleukin-1
- IL-6, interleukin-6
- IWGS, International Working Group on Sarcopenia
- LH, luteinizing hormone
- MELD, Model for End-Stage Liver Disease
- MuRF1, muscle RING-finger-1
- NAD, nicotinamide adenine dinucleotide
- NADH, nicotinamide adenine dinucleotide + hydrogen
- NADPH, nicotinamide adenine dinucleotide phosphate
- NAFLD, non-alcoholic fatty liver disease
- NASH, non-alcoholic steatohepatitis
- NF-κβ, nuclear factor κβ
- NHANES, National Health and Nutritional Examination Survey
- PMI, psoas muscle index
- PMTH, psoas muscle thickness
- RAAS, renin-angiotensin-aldosterone system
- ROS, reactive oxygen species
- SARC-F, Strength, Assistance with walking, Rise from a chair, Climb stairs, and Falls
- SHBG, sex hormone binding globulin
- SMI, skeletal muscle index
- SNS, sympathetic nervous system
- SPPB, Short Performance Physical Battery
- TNF-α, tumor necrosis factor α
- UCSF, University of California, San Francisco
- UNOS, United Network of Organ Sharing
- cirrhosis
- energy
- mTOR, mammalian target of rapamycin
- metabolism
- muscle
- sarcopenia
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Affiliation(s)
- Edgewood R. Warner II
- Department of Medicine, Donald and Barbara Zucker School of Medicine/Northwell Health, 300 Community Drive, Manhasset, NY, 11030, USA
| | - Sanjaya K. Satapathy
- Division of Hepatology and Northwell Health Center for Liver Diseases and Transplantation, Department of Medicine, Donald and Barbara Zucker School of Medicine/Northwell Health, 300 Community Drive, Manhasset, NY, 11030, USA
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Naguib R, Fayed A, Elkemary E, Naguib H. Serum Ghrelin Concentration in Patients With Primary Biliary Cirrhosis (PBC). Cureus 2021; 13:e20288. [PMID: 34912653 PMCID: PMC8664358 DOI: 10.7759/cureus.20288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2021] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION The appetite-modulating hormone ghrelin may have a role in the etiology of anorexia which is a serious concern in patients with primary biliary cirrhosis (PBC). This study aims to assess the difference in ghrelin level between cases of PBC and healthy controls matched for age and gender, and to evaluate the level of ghrelin in relation to clinical and laboratory findings among cases. METHODS Twenty patients with primary biliary cirrhosis and 30 healthy controls matched by gender and age were recruited. The severity of liver disease was determined using the Child-Pugh grading system. Clinical comorbidities such as a history of ascites, gastrointestinal bleeding, and encephalopathy were evaluated. A commercial enzyme-linked immunosorbent assay was used to measure total ghrelin. Results: PBC cases had a significantly higher average level of ghrelin (2305.3 ± 639.4) pg/mL compared to controls (682 ± 197.3) pg/mL. Furthermore, the minimum reported level in cases was 1258 pg/mL compared to 326 pg/mL in controls, while the maximum level nearly tripled the control's maximum level. In PBC patients, plasma levels of total ghrelin showed a weak positive correlation with age, an inverse correlation with body mass index, and were not associated with gender. The level was significantly higher than those in the controls. Ghrelin was associated with the severity of cirrhosis. Levels of serum ghrelin were higher in patients with associated comorbidities such as a history of ascites, gastrointestinal bleeding, and encephalopathy. CONCLUSIONS Our study demonstrated elevated serum ghrelin levels in patients with primary biliary cirrhosis. Serum ghrelin was associated with the degree of severity and the presence of related comorbidities. Patients with primary biliary cirrhosis remain anorexic and catabolic despite elevated ghrelin levels, suggesting tissue resistance to this anabolic peptide which could be crucial to understanding anorexia and cachexia in primary biliary cirrhosis.
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Affiliation(s)
- Rania Naguib
- Clinical Science Department, College of Medicine, Princess Nourah Bint Abdulrahman University, Riyadh, SAU.,Endocrinology Unit, Internal Medicine Department, Faculty of Medicine, Alexandria University, Alexandria, EGY
| | - Amel Fayed
- Clinical Science Department, College of Medicine, Princess Nourah Bint Abdulrahman University, Riyadh, SAU
| | - Eman Elkemary
- Clinical Pathology Department, Faculty of Medicine, Alexandria University, Alexandria, EGY
| | - Hend Naguib
- Hepatology Unit, Internal Medicine Department, Faculty of Medicine, Alexandria University, Alexandria, EGY
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Abstract
BACKGROUND A significant problem to be solved for patients after liver transplantation (LT) is malnutrition with anorexia in the early posttransplant period. We hypothesized that this problem was due to the change in ghrelin metabolism during LT. The aim of this study was to examine the balance of acyl ghrelin (AG) and desacyl ghrelin and the dependence of the regulation mechanism on hepatic-related enzymes in patients during LT. MATERIALS AND METHODS AG, desacyl ghrelin, and acyl/total ghrelin (A/T) concentrations in blood samples were measured in 15 patients with liver failure (LF), 15 patients after LT, and 10 controls. The correlations between the participants' ghrelin profiles and hepatic function-related data, including liver enzymes, were evaluated. In vitro assays using synthetic AG for assessment of deacylation activity in serum were performed. RESULTS AG and A/T ratio were significantly higher in the LF patients than the patients after LT and controls (AG: 25.9 ± 12.6 versus 16.4 ± 12.6 and 9.8 ± 7.6 fmol/mL, P < 0.05; A/T ratio: 17.4 ± 4.1 versus 12.2 ± 5.5 and 11.8% ± 5.9%, P < 0.05). The serum cholinesterase level was inversely correlated with AG and A/T ratio (P < 0.01). In vitro assays showed that deacylation activity was significantly lower in patients with LF than controls (10.5% versus 42.4%, 90 min; P < 0.01). Degradation of AG was partially suppressed by a cholinesterase inhibitor. CONCLUSIONS Deacylation activity was lower in LF patients, which could cause elevation of AG levels. Serum cholinesterase may be responsible for deacylation in humans.
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Abedelmalek S, Denguezli M, Chtourou H, Souissi N, Tabka Z. Does Ramadan fasting affect acylated ghrelin and growth hormone concentrations during short-term maximal exercise in the afternoon? BIOL RHYTHM RES 2015. [DOI: 10.1080/09291016.2015.1048949] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Pita-Gutierrez F, Pertega-Diaz S, Pita-Fernandez S, Pena L, Lugo G, Sangiao-Alvarellos S, Cordido F. Place of preoperative treatment of acromegaly with somatostatin analog on surgical outcome: a systematic review and meta-analysis. PLoS One 2013; 8:e61523. [PMID: 23634209 PMCID: PMC3636268 DOI: 10.1371/journal.pone.0061523] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/11/2013] [Indexed: 12/19/2022] Open
Abstract
Context Transsphenoidal neurosurgery is the accepted first-line treatment of acromegaly in the majority of patients. Previous studies addressing preoperative somatostatin analog (SSA) treatment and subsequent surgical cure rates are conflicting, reporting either benefits or no significant differences. Objective The aim of this study, based on a meta-analysis of all published reports, was to investigate whether treatment with SSA before surgery improves the surgical outcome of acromegaly. Data Sources All studies of preoperative treatment of acromegaly with SSA were systematically reviewed up to December 2011. We searched the Medline, Embase, Cochrane and Google Scholar electronic databases. Study Selection: The primary endpoint was the biochemical postoperative cure rate. We identified 286 studies, out of which 10 studies (3.49%) fulfilling the eligibility criteria were selected for analysis; five retrospective studies with a control group, two prospective non-randomized trials, and three prospective controlled trials. The meta-analysis was conducted using the random-effects model. Data Extraction Data were extracted from published reports by two independent observers. Data Synthesis: A borderline effect was detected in the analysis of all of the trials with control groups, with a pooled odds ratio (OR) for biochemical cure with SSA treatment of 1.62 (95% CI, 0.93–2.82). In the analysis of the three prospective controlled trials, a statistically significant effect was idenfified OR: 3.62 (95% CI, 1.88–6.96). Conclusions Preoperative treatment with SSA og GH-secreting pituitary adenomas shows a significant improvement on surgical results. This meta-analysis suggests that in centers without optimal results all patients with a GH-secreting pituitary macroadenoma should be treated with a long-acting SSA prior to surgical treatment.
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Affiliation(s)
| | - Sonia Pertega-Diaz
- Clinical Epidemiology and Biostatistics Unit, University Hospital A Coruña, A Coruña, Spain
| | | | - Lara Pena
- Department of Investigation, University Hospital A Coruña, A Coruña, Spain
| | - Gloria Lugo
- Department of Endocrinology, University Hospital A Coruña, A Coruña, Spain
| | - Susana Sangiao-Alvarellos
- Department of Investigation, University Hospital A Coruña, A Coruña, Spain
- Department of Medicine, University of A Coruña, A Coruña, Spain
| | - Fernando Cordido
- Department of Endocrinology, University Hospital A Coruña, A Coruña, Spain
- Department of Investigation, University Hospital A Coruña, A Coruña, Spain
- Department of Medicine, University of A Coruña, A Coruña, Spain
- * E-mail:
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Gonciarz M, Bielański W, Partyka R, Brzozowski T, Konturek PC, Eszyk J, Celiński K, Reiter RJ, Konturek SJ. Plasma insulin, leptin, adiponectin, resistin, ghrelin, and melatonin in nonalcoholic steatohepatitis patients treated with melatonin. J Pineal Res 2013; 54:154-61. [PMID: 22804755 DOI: 10.1111/j.1600-079x.2012.01023.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Insulin resistance, oxidative stress, and an abnormal production of adipokines and cytokines are implicated in the pathogenesis of nonalcoholic steatohepatitis (NASH). Recently, we reported a significant improvement in plasma liver enzymes among patients with NASH treated with melatonin. In this study, we investigated the effect of melatonin, administered at a dose of 10 mg/day for 28 days to 16 patients with histologically proven NASH on insulin resistance (HOMA-IR), on the plasma levels of adiponectin, leptin, ghrelin, and resistin. Additionally, plasma levels of aminotransferases and gamma glutamyltranspeptidase as well as plasma concentrations of melatonin were evaluated. Median baseline values of HOMA-IR, leptin (ng/mL), and resistin (pg/mL) in patients with NASH were significantly higher in comparison with controls: 4.90 versus 1.60, 10.70 versus 4.30, and 152 versus 91, respectively. Median adiponectin level (μg/mL) was decreased in patients compared to controls: 6.40 versus 16.25; no significant difference in ghrelin levels between patients and controls was found. After melatonin treatment, the median value of HOMA-IR was significantly reduced by 60% as compared to baseline values, whereas adiponectin, leptin, and ghrelin plasma levels rose significantly by 119%, 33%, and 20%, respectively; the difference between pre-/posttreatment in plasma resistin levels was not significant. These findings make melatonin a suitable candidate for testing in patients with NASH in the large controlled clinical trials.
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Affiliation(s)
- Maciej Gonciarz
- Department of Gastroenterology, St Barbara's Main District Hospital, Sosnowiec, Poland
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The role of gut hormones in controlling the food intake. What is their role in emerging diseases? ACTA ACUST UNITED AC 2012; 59:197-206. [DOI: 10.1016/j.endonu.2011.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 11/22/2011] [Accepted: 11/28/2011] [Indexed: 12/22/2022]
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Lugo G, Pena L, Cordido F. Clinical manifestations and diagnosis of acromegaly. Int J Endocrinol 2012; 2012:540398. [PMID: 22518126 PMCID: PMC3296170 DOI: 10.1155/2012/540398] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 10/30/2011] [Accepted: 10/30/2011] [Indexed: 12/24/2022] Open
Abstract
Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal.
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Affiliation(s)
- Gloria Lugo
- Department of Endocrinology, University Hospital A Coruña, Xubias deArriba 84, 15006 A Coruña, Spain
| | - Lara Pena
- Department of Investigation, University Hospital A Coruña, Xubias de Arriba 84, 15006 A Coruña, Spain
| | - Fernando Cordido
- Department of Endocrinology, University Hospital A Coruña, Xubias deArriba 84, 15006 A Coruña, Spain
- Department of Medicine, University of A Coruña, 15006 A Coruña, Spain
- *Fernando Cordido:
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Influence of a long-term high-fat diet on ghrelin secretion and ghrelin-induced food intake in rats. ACTA ACUST UNITED AC 2011; 173:60-3. [PMID: 21971115 DOI: 10.1016/j.regpep.2011.09.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/30/2011] [Accepted: 09/16/2011] [Indexed: 11/22/2022]
Abstract
The aims of this study were: (1) to define the extent to which a high-fat (HF) diet given on a long-term basis reduces resting plasma ghrelin (total [acyl+des-acyl]) levels and the plasma ghrelin (total) response to fasting, (2) to determine whether a chronic HF diet modifies the orexigenic activity of acyl-ghrelin, (3) whether insulin pretreatment inhibits the plasma ghrelin (total) response to fasting, and (4) the extent to which pioglitazone (PIO) treatment will increase stomach and plasma ghrelin (total) levels in rats fed a HF diet. PIO is a drug given to diabetics which improves insulin resistance. Our findings show that a chronic HF diet given for either 10 or 60 weeks exerts a persistent inhibitory effect on resting plasma ghrelin (total) levels. Additionally, the plasma ghrelin (total) elevation to overnight fasting is not altered in rats fed a HF diet on a long-term basis. A HF diet does not impair the ingestive response to acyl-ghrelin. Together, these results suggest that acyl-ghrelin serves as an important orexigenic factor. Results show that insulin pretreatment does not inhibit the plasma ghrelin (total) response to fasting suggesting that meal-induced insulin secretion does not have a role in reducing ghrelin (total) secretion. In rats fed a HF diet, PIO administration increases stomach ghrelin (total) levels. Because PIO can reduce systemic glucose and lipid levels, our findings suggest that elevated glucose and lipid levels are part of the inhibitory mechanism behind reduced ghrelin (total) secretion in rats fed a HF diet.
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Elbadri A, Esmat S, Abosaif N, Morsi A, Shaker O. Study of serum ghrelin changes and its correlation with malnutrition in liver cirrhosis in Egypt. Clin Res Hepatol Gastroenterol 2011; 35:638-43. [PMID: 21872552 DOI: 10.1016/j.clinre.2011.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 06/23/2011] [Accepted: 07/11/2011] [Indexed: 02/04/2023]
Abstract
Egypt has the highest prevalence of hepatitis C virus (HCV) all over the world, with an estimated 8-10 million among a population of 68 million having been exposed to the virus and 5-7 million active infections (Frank et al., 2000). It is considered the most common aetiology of chronic liver disease (CLD) in Egypt, where prevalence of antibodies to HCV (anti-HCV) is 10-fold greater than in the United States and Europe (Goldstone et al., 2002; Strickland et al., 2002). We have studied the role of plasma ghrelin, an orexigenic hormone that was found to correlate with malnourishment in CLD depending on Child classification. Sixty patients were divided in three groups according to Child classification and were compared to normal healthy controls (20 subjects). There was a highly significant correlation of plasma ghrelin and body mass index (BMI), mid arm circumference (MAC), waist circumference (WC) and tricuspid skin fold thickness (TSF). Also plasma ghrelin was specific and sensitive by the ROC curve analysis to BMI, which would indicate a new marker for malnourishment and possibility of a novel therapeutic approach.
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Affiliation(s)
- Ahmed Elbadri
- Internal Medicine Department, Cairo University, Cairo, Egypt
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Álvarez-Castro P, Sangiao-Alvarellos S, Brandón-Sandá I, Cordido F. [Endocrine function in obesity]. ACTA ACUST UNITED AC 2011; 58:422-32. [PMID: 21824829 DOI: 10.1016/j.endonu.2011.05.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 05/28/2011] [Accepted: 05/31/2011] [Indexed: 12/28/2022]
Abstract
Obesity is associated to significant disturbances in endocrine function. Hyper insulinemia and insulin resistance are the best known changes in obesity, but their mechanisms and clinical significance are not clearly established. Adipose tissue is considered to be a hormone-secreting endocrine organ; and increased leptin secretion from the adipocyte, a satiety signal, is a well-established endocrine change in obesity. In obesity there is a decreased GH secretion. Impairment of somatotropic function in obesity is functional and may be reversed in certain circumstances. The pathophysiological mechanism responsible for low GH secretion in obesity is probably multifactorial. There are many data suggesting that a chronic state of somatostatin hypersecretion results in inhibition of GH release. Increased FFA levels, as well as a deficient ghrelin secretion, probably contribute to the impaired GH secretion. In women, abdominal obesity is associated to hyperandrogenism and low sex hormone-binding globulin levels. Obese men, particularly those with morbid obesity, have decreased testosterone and gonadotropin levels. Obesity is associated to an increased cortisol production rate, which is compensated for by a higher cortisol clearance, resulting in plasma free cortisol levels that do not change when body weight increases. Ghrelin is the only known circulating orexigenic factor, and has been found to be decreased in obese people. In obesity there is also a trend to increased TSH and free T3 levels.
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