209 results on '"Jerry R, Greenfield"'
Search Results
52. Autoantibody-Negative Type 1 Diabetes: A Neglected Subtype
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Spiros Fourlanos, Jerry R. Greenfield, Cindy S. Ma, and Shivani K. Patel
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endocrine system ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Population ,030209 endocrinology & metabolism ,Autoimmunity ,Disease ,medicine.disease_cause ,03 medical and health sciences ,Islets of Langerhans ,0302 clinical medicine ,Endocrinology ,Immunophenotyping ,immune system diseases ,Diabetes mellitus ,Medicine ,Humans ,education ,Autoantibodies ,education.field_of_study ,Type 1 diabetes ,business.industry ,Autoantibody ,nutritional and metabolic diseases ,medicine.disease ,Precision medicine ,Diabetes Mellitus, Type 1 ,Immunology ,business - Abstract
Up to 15% of individuals with a clinical phenotype of type 1 diabetes (T1D) do not have evidence of seropositivity for pancreatic islet autoantibodies. On this basis, they are classified as nonimmune or idiopathic, and remain an understudied population, as they are excluded from T1D immunomodulatory trials. Our limited understanding of the disease aetiopathogenesis in autoantibody-negative T1D hinders our ability to improve diagnostic pathways and discover novel therapeutic agents; particularly as we progress towards an era of precision medicine. This review summarises the current understanding and challenges in studying autoantibody-negative T1D. We review the literature regarding T1D classification, and the role of autoimmunity and defects in the immunogenic pathway that may distinguish autoantibody-positive and -negative T1D.
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- 2020
53. Segregation of a latent high adiposity phenotype in families with a history of type 2 diabetes mellitus implicates rare obesity-susceptibility genetic variants with large effects in diabetes-related obesity.
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Arthur B Jenkins, Marijka Batterham, Dorit Samocha-Bonet, Katherine Tonks, Jerry R Greenfield, and Lesley V Campbell
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Medicine ,Science - Abstract
BACKGROUND: We recently reported significantly greater weight gain in non-diabetic healthy subjects with a 1(st) degree family history (FH+) of type 2 diabetes mellitus (T2DM) than in a matched control group without such history (FH-) during voluntary overfeeding, implying co-inheritance of susceptibilities to T2DM and obesity. We have estimated the extent and mode of inheritance of susceptibility to increased adiposity in FH+. METHODS: Normoglycaemic participants were categorised either FH+ (≥1 1(st) degree relative with T2DM, 50 F/30 M, age 45 ± 14 (SD) yr) or FH- (71F/51M, age 43 ± 14 yr). Log-transformed anthropometric measurements (height, hip and waist circumferences) and lean, bone and fat mass (Dual Energy X-ray Absorptiometry) data were analysed by rotated Factor Analysis. The age- and gender-adjusted distributions of indices of adiposity in FH+ were assessed by fits to a bimodal model and by relative risk ratios (RR, FH+/FH-) and interpreted in a purely genetic model of FH effects. RESULTS: The two orthogonal factors extracted, interpretable as Frame and Adiposity accounted for 80% of the variance in the input data. FH+ was associated with significantly higher Adiposity scores (p
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- 2013
- Full Text
- View/download PDF
54. COVID‐19: it's changed us
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Jerry R. Greenfield and Jennifer R Snaith
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2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pneumonia, Viral ,General Correspondence ,Betacoronavirus ,Physicians ,Pandemic ,Internal Medicine ,medicine ,Humans ,Letters to the Editor ,Letter to the Editor ,Pandemics ,biology ,Viral Epidemiology ,business.industry ,SARS-CoV-2 ,Australia ,COVID-19 ,medicine.disease ,biology.organism_classification ,Virology ,Pneumonia ,business ,Coronavirus Infections - Published
- 2020
55. Plasma Bile Acids More Closely Align With Insulin Resistance, Visceral and Hepatic Adiposity Than Total Adiposity
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Ramy H Bishay, Dorit Samocha-Bonet, Donald J. Chisholm, Katherine T. Tonks, Gideon Meyerowitz-Katz, Jacob George, Jerry R. Greenfield, and David E. James
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Male ,medicine.medical_specialty ,FGF21 ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Context (language use) ,Type 2 diabetes ,Intra-Abdominal Fat ,Biochemistry ,Bile Acids and Salts ,Cohort Studies ,Endocrinology ,Insulin resistance ,Internal medicine ,Medicine ,Humans ,Adiposity ,Aged ,Adiponectin ,business.industry ,Biochemistry (medical) ,Australia ,Organ Size ,Middle Aged ,medicine.disease ,Lipid Metabolism ,Obesity ,Fatty Liver ,Diabetes Mellitus, Type 2 ,Liver ,Obesity, Abdominal ,Homeostatic model assessment ,Body Composition ,Glucose Clamp Technique ,Female ,Insulin Resistance ,business ,Body mass index - Abstract
Context The etiological mechanism of bile acid (BA) effects on insulin resistance and obesity is unknown. Objective This work aimed to determine whether plasma BAs are elevated in human obesity and/or insulin resistance. Methods This observational study was conducted at an academic research center. Seventy-one adult volunteers formed 4 groups: lean insulin-sensitive (body mass index [BMI] ≤ 25 kg/m2, Homeostatic Model Assessment of Insulin Resistance [HOMA-IR] 25 kg/m2, HOMA-IR 25 kg/m2, HOMA-IR > 3.0, n = 20), and type 2 diabetes (T2D, n = 21). Main outcome measures included insulin sensitivity by hyperinsulinemic-euglycemic clamp, body composition by dual energy x-ray absorptiometry, abdominal fat distribution, and liver density by computed tomography and plasma BA. Results In the Obresistant group, glucose infusion rate/fat-free mass (GIR/FFM, an inverse measure of insulin resistance) was significantly lower, and visceral and liver fat higher, compared to lean and Obsensitive individuals, despite similar total adiposity in Obresistant and Obsensitive. Total BA concentrations were higher in Obresistant (2.62 ± 0.333 mmol/L, P = .03) and T2D (3.36 ± 0.582 mmol/L, P < .001) vs Obsensitive (1.16 ± 0.143 mmol/L), but were similar between Obsensitive and lean (2.31 ± 0.329 mmol/L) individuals. Total BAs were positively associated with waist circumference (R = 0.245, P = .041), visceral fat (R = 0.360, P = .002), and fibroblast growth factor 21 (R = 0.341, P = .004) and negatively associated with insulin sensitivity (R = –0.395, P = .001), abdominal subcutaneous fat (R = –0.352, P = .003), adiponectin (R = –0.375, P = .001), and liver fat (Hounsfield units, an inverse marker of liver fat, R = –0.245, P = .04). Conjugated BAs were additionally elevated in T2D individuals (P Conclusions BA concentrations correlated with abdominal, visceral, and liver fat in humans, though an etiological role in insulin resistance remains to be verified.
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- 2020
56. Multisystem Progeroid Syndrome With Lipodystrophy, Cardiomyopathy, and Nephropathy Due to an LMNA p.R349W Variant
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Iram Hussain, Frank Vuitch, Robert A. Hegele, Howard B. A. Baum, Jerry R. Greenfield, Barbara Gisella Carranza-Leon, Kathy H C Wu, MacRae F. Linton, Anil K. Agarwal, Ruilin Raelene Jin, Chao Xing, Sophie Devery, Junko Oshima, Abhimanyu Garg, and Débora Rossi Precioso
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Progeria ,business.industry ,Endocrinology, Diabetes and Metabolism ,Partial Lipodystrophy ,Cardiomyopathy ,030209 endocrinology & metabolism ,medicine.disease ,Nephropathy ,LMNA ,Mandibuloacral dysplasia ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Focal segmental glomerulosclerosis ,medicine ,Lipodystrophy ,business - Abstract
Background Pathogenic variants in lamin A/C (LMNA) cause a variety of progeroid disorders including Hutchinson-Gilford progeria syndrome, mandibuloacral dysplasia, and atypical progeroid syndrome. Six families with 11 patients harboring a pathogenic heterozygous LMNA c.1045C>T; p.R349W variant have been previously reported to have partial lipodystrophy, cardiomyopathy, and focal segmental glomerulosclerosis (FSGS), suggesting a distinct progeroid syndrome. Methods We report 6 new patients with a heterozygous LMNA p.R349W variant and review the phenotype of previously reported patients to define their unique characteristics. We also performed functional studies on the skin fibroblasts of a patient to seek the underlying mechanisms of various clinical manifestations. Results Of the total 17 patients, all 14 adults with the heterozygous LMNA p.R349W variant had peculiar lipodystrophy affecting the face, extremities, palms, and soles with variable gain of subcutaneous truncal fat. All of them had proteinuric nephropathy with FSGS documented in 7 of them. Ten developed cardiomyopathy, and 2 of them died early at ages 33 and 45 years. Other common features included premature graying, alopecia, high-pitched voice, micrognathia, hearing loss, and scoliosis. Metabolic complications, including diabetes mellitus, hypertriglyceridemia, and hepatomegaly, were highly prevalent. This variant did not show any abnormal splicing, and no abnormal nuclear morphology was noted in the affected fibroblasts. Conclusions The heterozygous LMNA p.R349W variant in affected individuals has several distinct phenotypic features, and these patients should be classified as having multisystem progeroid syndrome (MSPS). MSPS patients should undergo careful assessment at symptom onset and yearly metabolic, renal, and cardiac evaluation because hyperglycemia, hypertriglyceridemia, FSGS, and cardiomyopathy cause major morbidity and mortality.
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- 2020
57. Letter to the Editor: 'Risk Factors for Cardiovascular Disease (CVD) in Adults with Type 1 Diabetes: Findings from Prospective Real-life T1D Exchange Registry'
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Jennifer R, Snaith, Deborah J, Holmes-Walker, and Jerry R, Greenfield
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Adult ,Clinical Research Article ,Diabetes Mellitus, Type 1 ,Cardiovascular Diseases ,Heart Disease Risk Factors ,Risk Factors ,Humans ,cardiovascular diseases ,Prospective Studies ,Registries - Abstract
CONTEXT: Cardiovascular disease (CVD) is a major cause of mortality in adults with type 1 diabetes. OBJECTIVE: We prospectively evaluated CVD risk factors in a large, contemporary cohort of adults with type 1 diabetes living in the United States. DESIGN: Observational study of CVD and CVD risk factors over a median of 5.3 years. SETTING: The T1D Exchange clinic network. PATIENTS: Adults (age ≥ 18 years) with type 1 diabetes and without known CVD diagnosed before or at enrollment. MAIN OUTCOME MEASURE: Associations between CVD risk factors and incident CVD were assessed by multivariable logistic regression. RESULTS: The study included 8,727 participants (53% female, 88% non-Hispanic white, median age 33 years [interquartile ratio {IQR} = 21, 48], type 1 diabetes duration 16 years [IQR = 9, 26]). At enrollment, median HbA1c was 7.6% (66 mmol/mol) (IQR = 6.9 [52], 8.6 [70]), 33% used a statin, and 37% used blood pressure medication. Over a mean follow-up of 4.6 years, 325 (3.7%) participants developed incident CVD. Ischemic heart disease was the most common CVD event. Increasing age, body mass index, HbA1c, presence of hypertension and dyslipidemia, increasing duration of diabetes, and diabetic nephropathy were associated with increased risk for CVD. There were no significant gender differences in CVD risk. CONCLUSION: HbA1c, hypertension, dyslipidemia and diabetic nephropathy are important risk factors for CVD in adults with type 1 diabetes. A longer follow-up is likely required to assess the impact of other traditional CVD risk factors on incident CVD in the current era.
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- 2020
58. MON-LB113 Insulin Resistance in Type 1 Diabetes Managed With Metformin (INTIMET): Rationale and Study Design of a Randomised Placebo-Controlled Trial
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Jerry R. Greenfield, Dorit Samocha-Bonet, D. J. Holmes-Walker, and Jennifer R Snaith
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Type 1 diabetes ,medicine.medical_specialty ,endocrine system diseases ,business.industry ,Endocrinology, Diabetes and Metabolism ,Placebo-controlled study ,nutritional and metabolic diseases ,medicine.disease ,Diabetes Mellitus and Glucose Metabolism ,Metformin ,Clinical and Translational Studies in Diabetes ,Insulin resistance ,Internal medicine ,medicine ,business ,AcademicSubjects/MED00250 ,medicine.drug - Abstract
Background: Insulin resistance is an under-recognised cardiovascular risk factor in type 1 diabetes (T1D). Individuals with T1D exhibit insulin resistance relative to those without diabetes. In T1D, tissue-specific insulin resistance (muscle, hepatic, adipose) is likely to partly drive increased cardiovascular risk. Adjunctive metformin improves muscle insulin sensitivity in T1D adolescents, but factors that predict responsiveness remain unknown.Objective: To report the rationale and design of the INTIMET study, a double-blind randomised, placebo-controlled trial of metformin in T1D.Methods: Forty adults aged 20-50 years with T1D, and 20 age- gender- and BMI- matched non-diabetic controls will be studied. T1D inclusion criteria are diagnosis > 10 years, HbA1c 9.5% and fasting C-peptide < 0.3nmol/L. Liver and muscle insulin sensitivity will be determined by the 2-stage hyperinsulinemic (20 and 60 mUm2)-euglycemic (5.5 mmol/L) clamp method with deuterated glucose. Subjects with T1D will be randomised to metformin extended-release 1500mg/d or matched placebo for 26 weeks. The primary endpoint is the change in hepatic insulin sensitivity, measured by suppression of endogenous glucose production (EGP) with the low-dose insulin clamp. Secondary endpoints include change in muscle and adipose tissue insulin sensitivity, arterial stiffness, HbA1c, glucose variability, frequency of hypoglycemia, insulin dose, anthropometry, body composition, lipid profile, liver fat and stiffness. Conclusion: The INTIMET study will quantify muscle, liver and adipose insulin-resistance in T1D, determine whether metformin is effective in improving insulin resistance in T1D and identify factors that predict metformin-responsiveness. The trial is registered (Australian New Zealand Clinical Trial Registry, ACTRN12619001440112) and is actively recruiting in Sydney, Australia.
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- 2020
59. SAT-LB75 Thyroid Peroxidase Antibody Positivity Predicts Relapse Free Survival Following Anti-Thyroid Drug Treatment for Graves Disease
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Graham R D Jones, Christopher A. Muir, Katherine Samaras, Andrew Weissberger, and Jerry R. Greenfield
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Thyroid ,endocrine system ,medicine.medical_specialty ,endocrine system diseases ,biology ,business.industry ,Endocrinology, Diabetes and Metabolism ,Graves' disease ,Benign Thyroid Disease and Health Disparities in Thyroid I ,medicine.disease ,Gastroenterology ,Relapse free survival ,eye diseases ,Thyroid peroxidase ,Internal medicine ,Anti thyroid drug ,biology.protein ,medicine ,business ,AcademicSubjects/MED00250 - Abstract
Objective: Graves disease is an autoimmune disease characterized by production of autoantibodies directed against the thyroid gland. Thyrotropin-receptor antibodies (TRABs) are clearly pathogenic, but the role of thyroid-peroxidase antibodies (TPOAb) in Graves disease is unknown. Design: We retrospectively studied whether TPOAb positivity reduced risk of relapse following anti-thyroid drug treatment in newly diagnosed Graves disease. Results: During follow-up of 204 patients with TRAB positive Graves disease, 107 (52%) relapsed following withdrawal of anti-thyroid medication. Mean age was 40.0 years and 82% were female. The average duration of anti-thyroid drug (ATD) treatment was 23.5 months and was not different between patients who relapsed and those with sustained remission. Absence of TPOAb significantly increased risk of Graves relapse (OR 2.21) and displayed a trend towards shorter time to relapse. Male sex and younger age were additional factors significantly associated with increased risk of relapse. Conclusion: TPO-antibody positivity significantly improves odds of remission following ATD treatment in newly diagnosed Graves disease.
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- 2020
60. Thyroid Peroxidase Antibody Positivity is Associated With Relapse-Free Survival Following Antithyroid Drug Treatment for Graves Disease
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Graham R D Jones, Jerry R. Greenfield, Andrew Weissberger, Katherine Samaras, and Christopher A. Muir
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Adult ,Male ,endocrine system ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,Graves' disease ,030209 endocrinology & metabolism ,Disease ,Gastroenterology ,Iodide Peroxidase ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Antithyroid Agents ,Thyroid peroxidase ,Recurrence ,Internal medicine ,Medicine ,Humans ,030212 general & internal medicine ,Autoantibodies ,Retrospective Studies ,Autoimmune disease ,biology ,business.industry ,Thyroid ,Autoantibody ,Retrospective cohort study ,Receptors, Thyrotropin ,General Medicine ,Odds ratio ,medicine.disease ,eye diseases ,Graves Disease ,medicine.anatomical_structure ,biology.protein ,Female ,business - Abstract
Objective: Graves’ disease is an autoimmune disease characterized by production of autoantibodies directed against the thyroid gland. Thyrotropin-receptor antibodies (TRAbs) are clearly pathogenic, but the role of thyroidperoxidase antibodies (TPOAbs) in Graves disease is unknown. Methods: We retrospectively studied whether TPOAb positivity reduced risk of relapse following antithyroid drug (ATD) treatment in newly diagnosed Graves disease. Results: During follow-up of 204 patients with TRAb-positive Graves disease, 107 (52%) relapsed following withdrawal of ATD. Mean age was 40.0 years, and 82% were female. The average duration of ATD treatment was 23.5 months and was not different between patients who relapsed and those with sustained remission. Absence of TPOAbs significantly increased risk of Graves relapse (odds ratio, 2.21). Male sex and younger age were other factors significantly associated with increased risk of relapse. Conclusion: TPOAb positivity significantly improves the odds of remission following ATD treatment in newly diagnosed Graves’ disease.
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- 2020
61. Acute illness in patients with concomitant Addison's disease and type 1 diabetes mellitus: Increased incidence of hypoglycaemia and adrenal crises
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Vaidehi Dhirendra Naganur, Paul Satouris, Brienna Mortimer, Jerry R. Greenfield, David J. Torpy, and Rosemary Louise Rushworth
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medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Addison Disease ,Internal medicine ,medicine ,Adrenal insufficiency ,Humans ,Hydrocortisone ,Type 1 diabetes ,business.industry ,Incidence (epidemiology) ,Incidence ,nutritional and metabolic diseases ,Adrenal crisis ,Emergency department ,medicine.disease ,Hypoglycemia ,Diabetes Mellitus, Type 1 ,030220 oncology & carcinogenesis ,Concomitant ,Addison's disease ,Acute Disease ,medicine.symptom ,business ,medicine.drug - Abstract
BACKGROUND Patients with Addison's disease (AD) and comorbid type 1 diabetes mellitus (T1DM) are at increased risk of certain acute metabolic disorders relative to patients with one of these conditions only. The reasons for this are unknown. METHODS All attendances for acute illness by AD patients at the emergency department of a Sydney hospital between 2000 and 2017 were reviewed. Physiological parameters and illness management strategies were compared between AD patients, those with T1DM and AD combined, and a control group of patients with T1DM. RESULTS There were 39 presentations for an acute medical illness by 20 nondiabetic AD (28 attendances) and 5 diabetic AD patients (11 presentations) and 40 attendances by 10 T1DM controls. In AD patients, 17 (43.6%) attendances were medically diagnosed adrenal crises (AC) (63.6% [n = 7] in diabetic AD and 35.7% [n = 10] in nondiabetic AD). This corresponded to an estimated incidence of 12.5 AC/100 patient-years (PY) for diabetic AD patients compared to 4.7 AC/100PY for nondiabetic AD patients (P
- Published
- 2020
62. Overfeeding reduces insulin sensitivity and increases oxidative stress, without altering markers of mitochondrial content and function in humans.
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Dorit Samocha-Bonet, Lesley V Campbell, Trevor A Mori, Kevin D Croft, Jerry R Greenfield, Nigel Turner, and Leonie K Heilbronn
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Medicine ,Science - Abstract
Mitochondrial dysfunction and increased oxidative stress are associated with obesity and type 2 diabetes. High fat feeding induces insulin resistance and increases skeletal muscle oxidative stress in rodents, but there is controversy as to whether skeletal muscle mitochondrial biogenesis and function is altered.Forty (37 ± 2 y) non-obese (25.6 ± 0.6 kg/m(2)) sedentary men (n = 20) and women (n = 20) were overfed (+1040 ± 100 kcal/day, 46 ± 1% of energy from fat) for 28 days. Hyperinsulinemic-euglycemic clamps were performed at baseline and day 28 of overfeeding and skeletal muscle biopsies taken at baseline, day 3 and day 28 of overfeeding in a sub cohort of 26 individuals (13 men and 13 women) that consented to having all 3 biopsies performed. Weight increased on average in the whole cohort by 0.6 ± 0.1 and 2.7 ± 0.3 kg at days 3 and 28, respectively (P
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- 2012
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63. High prevalence of diabetes before and after lung transplantation: target for improving outcome?
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Marshall Plit, Michael Reyes, Monika Fazekas-Lavu, Monique A. Malouf, Jerry R. Greenfield, Adrian Havryk, Lesley V. Campbell, and Allan R. Glanville
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medicine.medical_specialty ,Lung ,High prevalence ,business.industry ,medicine.medical_treatment ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,medicine.disease ,Impaired fasting glucose ,Cystic fibrosis ,Impaired glucose tolerance ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,medicine ,Endocrine system ,Lung transplantation ,business - Abstract
Background Diabetes increases morbidity and mortality of lung transplantation. However, the reported prevalence of diabetes varies post-transplantation partly due to lack of detection protocols. Aim To determine the prevalence of diabetes in patients (i) waitlisted for lung transplant and (ii) early post-transplantation. Methods We analysed patients on the St Vincent's Heart Lung database from 1 April 2014 to 30 September 2015 on the waitlist (Study 1) and those transplanted (Study 2). Standard of care required all non-diabetic patients to have an oral glucose tolerance test (modified for patients with cystic fibrosis (CF) to screen for CF-related hyperglycaemia (CFRH) (plasma glucose ≥8.2 mmol/L at 60 or 90 min). Results Study 1 included 114 patients (32 with CF and 82 without CF). Of 30 CF patients with glycaemic data, 27 (90%) had abnormal glucose metabolism: 18 had diabetes and nine had CFRH. In 50 patients without CF, 20 (40%) had abnormal glucose metabolism: eight had diabetes and 12 had impaired fasting glucose and/or impaired glucose tolerance. Study 2 included 78 transplanted patients (25 with CF and 53 without CF). Fourteen CF patients had pre-existing diabetes and seven had pre-existing CFRH. All but one patient were diagnosed with diabetes post-transplantation. Hence, diabetes prevalence in CF patients post-transplantation was 96%. Among 53 transplanted patients without CF, seven (13%) had abnormal glucose metabolism but 30 (57%) were diagnosed with post-transplant diabetes. Conclusion There is a high prevalence of diabetes in lung transplant patients. Earlier endocrine participation in lung transplant services is likely to lower diabetes-related morbidity and mortality further.
- Published
- 2018
64. Prevention and Treatment of Type 2 Diabetes: A Pathophysiological-Based Approach
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Jerry R. Greenfield, Dorit Samocha-Bonet, and Sophie Debs
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0301 basic medicine ,medicine.medical_specialty ,endocrine system diseases ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Type 2 diabetes ,law.invention ,Prediabetic State ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Randomized controlled trial ,law ,Diabetes mellitus ,Internal medicine ,medicine ,Animals ,Humans ,Prediabetes ,Glycemic ,business.industry ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,Genomics ,medicine.disease ,Omics ,Metformin ,Gastrointestinal Microbiome ,030104 developmental biology ,Diabetes Mellitus, Type 2 ,business ,medicine.drug - Abstract
Prediabetes affects approximately 40% of American adults. Randomized trials report that a proportion of individuals with prediabetes develop diabetes despite caloric restriction, physical activity, and/or when treated with metformin, the first-line medication for patients with type 2 diabetes mellitus (T2DM). Currently, there are no valid predictors of the effectiveness of these measures in determining who will and who will not progress to the T2DM state. Few studies have examined the clinical and phenotypic predictors of better and worse glycemic response to lifestyle interventions and metformin in prediabetes and diabetes. Further studies incorporating 'omic' approaches to discover novel markers of phenotypes and treatment effectiveness may pave the way to personalizing the treatment of prediabetes and diabetes.
- Published
- 2018
65. Complex interplay among adiposity, insulin resistance and bone health
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C Ma, Katherine T. Tonks, Dorit Samocha-Bonet, and Jerry R. Greenfield
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0301 basic medicine ,medicine.medical_specialty ,Bone density ,business.industry ,Endocrinology, Diabetes and Metabolism ,Public health ,Osteoporosis ,030209 endocrinology & metabolism ,Type 2 diabetes ,medicine.disease ,Obesity ,Bone health ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,Internal medicine ,medicine ,Osteoporotic fracture ,business - Abstract
Obesity and osteoporosis are common public health problems. Paradoxically, while obesity is associated with higher bone density, type 2 diabetic obese individuals have an increased fracture risk. Although obesity and insulin resistance co-exist, some obese individuals remain insulin-sensitive. We suggest that the apparent paradox relating obesity, bone density and fracture risk in type 2 diabetes may be at least partly influenced by differences in bone strength and quality between insulin-resistant and insulin-sensitive obese individuals. In this review, we focus on the complex interplay between, adiposity, insulin resistance and osteoporotic fracture risk and suggest that this is an important area of study that has implications for individually tailored and targeted treatment to prevent osteoporotic fracture in obese type 2 diabetic individuals.
- Published
- 2018
66. Interpreting insulin immunoassays during investigation of apparent spontaneous hypoglycaemia and insulin overdose
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Jerry R. Greenfield, Graham R D Jones, Julie Chemmanam, Michelle Isaacs, and Morton G. Burt
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medicine.medical_specialty ,Insulin Analogue ,endocrine system diseases ,medicine.diagnostic_test ,business.industry ,Insulin ,medicine.medical_treatment ,nutritional and metabolic diseases ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,Insulin overdose ,Spontaneous hypoglycaemia ,03 medical and health sciences ,0302 clinical medicine ,Factitious hypoglycaemia ,Endocrinology ,Internal medicine ,Immunoassay ,Internal Medicine ,medicine ,ADVIA Centaur ,business ,hormones, hormone substitutes, and hormone antagonists - Abstract
We report two cases of hypoglycaemia; one with apparently spontaneous hypoglycaemia and one with presumed insulin overdose. In both cases insulin concentration was normal when measured with the Roche immunoassay, but elevated when remeasured with the Advia Centaur immunoassay and a diagnosis of hypoglycaemia secondary to insulin analogue administration was made. These cases highlight that physicians need to understand the binding characteristics of the insulin immunoassay they use.
- Published
- 2017
67. Prescribing of SGLT2 inhibitors in primary care: A qualitative study of General Practitioners and Endocrinologists
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Sophie L. Stocker, Richard O. Day, Jerry R. Greenfield, Tamara Y. Milder, and Melissa T. Baysari
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medicine.medical_specialty ,Primary Health Care ,Attitude of Health Personnel ,business.industry ,Endocrinology, Diabetes and Metabolism ,education ,General Medicine ,Primary care ,Endocrinologists ,Endocrinology ,Diabetes Mellitus, Type 2 ,General Practitioners ,Family medicine ,Internal Medicine ,medicine ,Humans ,Medical prescription ,business ,Sodium-Glucose Transporter 2 Inhibitors ,Qualitative Research ,Qualitative research - Abstract
Aims To explore: 1) General Practitioners’ (GPs’) perspectives regarding initiating SGLT2 inhibitors and the resources that inform their pharmacotherapy choices; and 2) The support provided to GPs by Endocrinologists in relation to the prescription of type 2 diabetes medications. Methods Semi-structured interviews with 15 GPs and 12 Endocrinologists working in diverse areas in New South Wales, Australia. Interviews were recorded, transcribed, and emergent themes were identified using a general inductive approach. Results Under-appreciation of the cardio-renal benefits of SGLT2 inhibitors, a preference for an Endocrinologist to initiate therapy, and patients’ experiences with adverse effects were identified as reasons for low rates of initiating SGLT2 inhibitors by some GPs. GPs reported that they would like to receive education about this topic from Endocrinologists, ideally via case-based discussions. A perceived challenge faced by Endocrinologists in providing GP education included potential constraints on talk content imposed by industry at sponsored events. Endocrinologists indicated that interactive sessions were most useful to GPs. Conclusions Despite the evidence for the cardio-renal benefits of SGLT2 inhibitors, there are barriers to GPs prescribing these agents. Case-based discussions between GPs and Endocrinologists about type 2 diabetes treatment including the role of SGLT2 inhibitors could overcome some of these barriers.
- Published
- 2021
68. Euglycaemic diabetic ketoacidosis in patients using sodium-glucose co-transporter 2 inhibitors
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Michelle Isaacs, Jerry R. Greenfield, and Katherine T. Tonks
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Sodium glucose transporter 2 ,medicine.medical_specialty ,Diabetic ketoacidosis ,business.industry ,Type 2 Diabetes Mellitus ,Transporter ,030204 cardiovascular system & hematology ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Internal medicine ,Internal Medicine ,medicine ,In patient ,030212 general & internal medicine ,business ,Complication - Abstract
Sodium-glucose co-transporter 2 inhibitors (SGLT2i) are an increasingly prescribed class of medication for type 2 diabetes mellitus. Euglycaemic diabetic ketoacidosis (euDKA) has been reported in association with SGLT2i use. Clinicians need to understand how to recognise and treat this complication. We describe three cases of euDKA in patients treated with SGLT2i.
- Published
- 2017
69. Low dose prednisolone and insulin sensitivity differentially affect arterial stiffness and endothelial function: An open interventional and cross-sectional study
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Campbell H. Thompson, Jerry R. Greenfield, Carolyn J. Petersons, Anne Poljak, Malcolm D. Smith, Morton G. Burt, and Brenda L. Mangelsdorf
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,Time Factors ,Prednisolone ,Inflammatory arthritis ,Administration, Oral ,Hyperemia ,Pulse Wave Analysis ,030204 cardiovascular system & hematology ,Drug Administration Schedule ,Arthritis, Rheumatoid ,03 medical and health sciences ,Hyperaemia ,Vascular Stiffness ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Insulin ,Glucocorticoids ,Pulse wave velocity ,Aged ,030203 arthritis & rheumatology ,business.industry ,Middle Aged ,medicine.disease ,Peripheral ,Cross-Sectional Studies ,Treatment Outcome ,Endocrinology ,Liver ,Rheumatoid arthritis ,Glucose Clamp Technique ,Arterial stiffness ,Female ,Endothelium, Vascular ,Insulin Resistance ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Glucocorticoid ,medicine.drug - Abstract
Background and aims Glucocorticoids could impair vascular function directly, or indirectly by reducing insulin sensitivity. The aim of this study was to determine the direct and indirect effects of acute and chronic low dose prednisolone on arterial stiffness and endothelial function. Methods Twelve subjects with inflammatory arthritis, who had not taken oral glucocorticoids for ≥6 months, and 12 subjects with inflammatory arthritis, taking chronic (>6 months) low dose (6.3 ± 2.2 mg/day) prednisolone, were studied. Patients not on glucocorticoids underwent measurement of arterial stiffness (pulse wave velocity (PWV)) and endothelial function (reactive hyperaemia index (RHI)) before and after 7–10 days of prednisolone (6 mg/day), to assess the acute effects of prednisolone. Baseline data from patients not on glucocorticoids were compared with patients on long-term prednisolone to assess the chronic effects of prednisolone. Hepatic insulin sensitivity was estimated from percentage suppression of endogenous glucose production and peripheral insulin sensitivity as glucose infusion rate (M/I) during a hyperinsulinaemic-euglycaemic clamp. Results There were no significant changes in PWV with acute (9.2 ± 0.8 vs. 8.9 ± 0.8 m/sec, p = 0.33) or chronic (8.9 ± 0.8 vs. 9.0 ± 0.7 m/sec, p = 0.69) prednisolone. In multiple regression analysis, PWV was negatively associated with M/I during hyperinsulinemic-euglycemic clamp ( p = 0.02), but not with suppression of endogenous glucose production ( p = 0.15) or glucocorticoid use ( p = 0.70). Chronic (2.4 ± 0.2 vs. 1.9 ± 0.1, p = 0.02), but not acute (1.8 ± 0.2 vs. 1.9 ± 0.1, p = 0.24), prednisolone resulted in a higher RHI. Conclusions Arterial stiffness is not affected by low dose prednisolone per se , but is negatively associated with peripheral insulin sensitivity. Patients with rheumatoid arthritis taking long-term prednisolone had better endothelial function.
- Published
- 2017
70. Bone Turnover Is Suppressed in Insulin Resistance, Independent of Adiposity
- Author
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Jerry R. Greenfield, Christopher J. White, Dorit Samocha-Bonet, and Katherine T. Tonks
- Subjects
Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Down-Regulation ,030209 endocrinology & metabolism ,Biochemistry ,Body Mass Index ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Insulin resistance ,N-terminal telopeptide ,Bone Density ,Diabetes mellitus ,Internal medicine ,medicine ,Hyperinsulinemia ,Humans ,Obesity ,Adiposity ,Aged ,Adiponectin ,business.industry ,Insulin ,Biochemistry (medical) ,Middle Aged ,medicine.disease ,030104 developmental biology ,Diabetes Mellitus, Type 2 ,Case-Control Studies ,Bone Remodeling ,Insulin Resistance ,business ,Hyperinsulinism ,Body mass index - Abstract
Context The contribution of insulin resistance vs adiposity to bone mineral density (BMD), bone turnover, and fractures in humans remains unclear. Objective To evaluate BMD and bone turnover markers (BTMs) in lean (n = 18) and overweight/obese individuals with (n = 17) and without (n = 34, insulin-sensitive [Obsensitive, n=15] or insulin-resistant [Obresistant, n=19] by homeostasis model assessment insulin resistance) diabetes mellitus. Design Observational study. Outcome measures Insulin sensitivity was assessed using the hyperinsulinemic-euglycemic clamp; whole body BMD and fat mass (FM) using dual energy X-ray absorptiometry; and by measurement of BTMs [osteocalcin (OC), procollagen type 1 N-terminal propeptide (P1NP), and collagen type 1 cross-linked C-terminal telopeptide (CTx)], with the patient fasting and during clamp hyperinsulinemia. Results Fasting BTMs correlated with glucose infusion rate/fat-free mass (GIR/FFM) and adiponectin and, inversely, with fasting insulin and visceral fat (P ≤ 0.04 for all). Obsensitive, Obresistant, and diabetic individuals were matched by their FM percentage. Clamp GIR/FFM was similar in the lean and Obsensitive subjects (P = 1) and approximately twofold greater (P < 0.001) than in the Obresistant and diabetic subjects. BMD was greater in Obresistant than in Obsensitive (P = 0.04) and lean (P = 0.001) subjects. At baseline, compared with Obsensitive and lean subjects, Obresistant and diabetic individuals had lower OC, P1NP, and CTx levels. This reached statistical significance for Obresistant vs lean and Obresistant vs Obsensitive for both OC and CTx and for diabetic vs lean for CTx (P ≤ 0.04 for all). During hyperinsulinemia, lean individuals suppressed CTx more than did diabetic individuals (P = 0.03). On multiple regression analysis, visceral adiposity explained 16.7% and 19.3% of the baseline OC and CTx variability, respectively. Conclusions Increased visceral adiposity and higher fasting insulin in insulin-resistant states are associated with lower fasting OC and CTx and failure to further suppress with more insulin.
- Published
- 2017
71. Pancreatic cancer-related diabetes: Do pancreatic stellate cell and cancer cell derived exosomes play a role?
- Author
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David Goldstein, Zhihong Xu, Sri Pothula, Jeremy S. Wilson, S. Hosen, M. Killlingsworth, Jerry R. Greenfield, Minoti V. Apte, Ron Pirola, Suresh T. Chari, T. Cohen-Hyams, Alpha Raj Mekapogu, and Chamini J. Perera
- Subjects
Hepatology ,business.industry ,Endocrinology, Diabetes and Metabolism ,Gastroenterology ,Pancreatic stellate cell ,medicine.disease ,Microvesicles ,medicine.anatomical_structure ,Pancreatic cancer ,Diabetes mellitus ,Cancer cell ,medicine ,Cancer research ,business - Published
- 2020
72. Should the cardio-protective properties of sodium-glucose cotransporter 2 inhibitors dictate therapeutic decision-making in patients with type 2 diabetes
- Author
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Sophie L. Stocker, Jerry R. Greenfield, Tamara Y. Milder, and Richard O. Day
- Subjects
business.industry ,Cardio protective ,Sodium ,MEDLINE ,Therapeutic decision making ,Type 2 diabetes ,Pharmacology ,medicine.disease ,Glucose ,Diabetes Mellitus, Type 2 ,Sodium/Glucose Cotransporter 2 ,Internal Medicine ,Medicine ,Humans ,Hypoglycemic Agents ,In patient ,business ,Sodium-Glucose Transporter 2 Inhibitors - Published
- 2019
73. The safety and pharmacokinetics of metformin in patients with chronic liver disease
- Author
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Jerry R. Greenfield, Sophie L. Stocker, Kenneth M. Williams, Garry G. Graham, Felicity C. Smith, Shaun S. Kumar, Hannah E. Braithwaite, Richard O. Day, Jane E. Carland, Tim S. Cheng, Zhixin Liu, and Mark Danta
- Subjects
Adult ,Male ,medicine.medical_specialty ,Cirrhosis ,endocrine system diseases ,Renal function ,Comorbidity ,Chronic liver disease ,Gastroenterology ,Severity of Illness Index ,03 medical and health sciences ,Liver disease ,0302 clinical medicine ,Pharmacokinetics ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Hypoglycemic Agents ,Pharmacology (medical) ,030212 general & internal medicine ,Lactic Acid ,Prospective Studies ,Aged ,Aged, 80 and over ,Hepatology ,business.industry ,Liver Diseases ,nutritional and metabolic diseases ,Middle Aged ,medicine.disease ,Metformin ,Cross-Sectional Studies ,Diabetes Mellitus, Type 2 ,Lactic acidosis ,Chronic Disease ,030211 gastroenterology & hepatology ,Acidosis, Lactic ,Female ,business ,medicine.drug - Abstract
BACKGROUND The FDA approved 'label' for metformin lists hepatic insufficiency as a risk for lactic acidosis. Little evidence supports this warning. AIMS To investigate the safety and pharmacokinetics of metformin in patients with chronic liver disease (CLD). METHODS Chronic liver disease patients with and without type 2 diabetes mellitus (T2DM) were studied by a cross-sectional survey of patients already prescribed metformin (n = 34), and by a prospective study where metformin (500 mg, immediate release, twice daily) for up to 6 weeks was prescribed (n = 24). Plasma metformin and lactate concentrations were monitored. Individual pharmacokinetics were obtained and compared to previously published values from healthy and T2DM populations without CLD. RESULTS All plasma metformin and lactate concentrations remained below the putative safety thresholds (metformin, 5 mg/L; lactate, 5 mmol/L). Lactate concentrations were unrelated to average steady-state metformin concentrations. In patients with CLD, T2DM was associated with higher plasma lactate concentrations (48% higher than those without T2DM, P
- Published
- 2019
74. Durvalumab-induced diabetic ketoacidosis followed by hypothyroidism
- Author
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Jerry R. Greenfield, Shivani K. Patel, and Venessa T. Chin
- Subjects
Weight loss ,Durvalumab ,C-peptide (blood) ,pH (blood) ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,December ,Levothyroxine ,White ,Gastroenterology ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Cortisol ,0302 clinical medicine ,Diabetes mellitus type 1 ,Diabetic ketoacidosis ,Insulin ,Hyperglycaemia ,FT4 ,Fatigue ,Thyroid ,medicine.diagnostic_test ,TSH ,Autoimmune disorders ,Bicarbonate ,Oncology ,030220 oncology & carcinogenesis ,Female ,Thyroid function ,medicine.drug ,Adult ,medicine.medical_specialty ,Insulin glargine ,Thyroxine (T4) ,030209 endocrinology & metabolism ,Glucose (blood) ,Thyroid function tests ,03 medical and health sciences ,Hypothyroidism ,GADA ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,Unusual Effects of Medical Treatment ,Polydipsia ,Pancreas ,Haemoglobin A1c ,Insulin Aspart ,lcsh:RC648-665 ,Beta-hydroxybutyrate ,business.industry ,Polyuria ,Australia ,Vision - blurred ,medicine.disease ,business ,Cortisol (9am) - Abstract
Summary Durvalumab is a programmed cell death ligand 1 inhibitor, which is now approved in Australia for use in non-small-cell lung and urothelial cancers. Autoimmune diabetes is a rare immune-related adverse effect associated with the use of immune checkpoint inhibitor therapy. It is now being increasingly described reflecting the wider use of immune checkpoint inhibitor therapy. We report the case of a 49-year-old female who presented with polyuria, polydipsia and weight loss, 3 months following the commencement of durvalumab. On admission, she was in severe diabetic ketoacidosis with venous glucose: 20.1 mmol/L, pH: 7.14, bicarbonate 11.2 mmol/L and serum beta hydroxybutyrate: >8.0 mmol/L. She had no personal or family history of diabetes or autoimmune disease. Her HbA1c was 7.8% and her glutamic acid decarboxylase (GAD) antibodies were mildly elevated at 2.2 mU/L (reference range: Learning points: Durvalumab use is rarely associated with fulminant autoimmune diabetes, presenting with severe DKA. Multiple endocrinopathies can co-exist with the use of a single immune checkpoint inhibitors; thus, patients should be regularly monitored. Regular blood glucose levels should be performed on routine pathology on all patients on immune checkpoint inhibitor. Clinician awareness of immunotherapy-related diabetes needs to increase in an attempt to detect hyperglycaemia early and prevent DKA.
- Published
- 2019
75. Urinary steroid profiling in diagnostic evaluation of an unusual adrenal mass
- Author
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Jerry R. Greenfield and N F Lenders
- Subjects
Pathology ,Hirsutism ,Endocrinology, Diabetes and Metabolism ,Laparoscopic adrenalectomy ,White ,Androgen Excess ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Cortisol ,0302 clinical medicine ,17ohp ,Novel Diagnostic Procedure ,Adrenocortical carcinoma ,Oncocytoma ,Testosterone ,Adrenal ,Fatigue ,medicine.diagnostic_test ,030220 oncology & carcinogenesis ,Female ,Dexamethasone suppression ,Adult ,CT scan ,medicine.medical_specialty ,Urinalysis ,Urinary system ,Histopathology ,030209 endocrinology & metabolism ,Malignancy ,Androsterone ,03 medical and health sciences ,BMI ,Internal Medicine ,medicine ,Obesity ,Glucocorticoids ,Lh ,lcsh:RC648-665 ,business.industry ,November ,Hyperandrogenism ,Australia ,Androstenedione ,medicine.disease ,Weight ,Acne ,Amenorrhoea ,Differential diagnosis ,business - Abstract
Summary Adrenal oncocytomas are rare tumours, with only approximately 160 cases reported in the literature. We report the use of urinary steroid profiling as part of their diagnostic evaluation and prognostication. A 45-year-old woman presented with clinical features of hyperandrogenism. Serum biochemistry confirmed androgen excess and computed tomography (CT) demonstrated a 3.2 cm adrenal tumour with density 39 HU pre-contrast. Urine steroid profiling showed elevated tetrahydro-11 deoxycortisol (THS), which is associated with adrenal malignancy. Laparoscopic adrenalectomy was performed, and histopathology diagnosed adrenal oncocytoma. Serum and urinary biochemistry resolved post-operatively and remained normal at 1-year follow-up. Learning points: Differential diagnosis of adrenal masses is challenging. Current techniques for differentiating between tumour types lack sensitivity and specificity. 24-h urinary steroid profiling is a useful tool for reflecting steroid output from adrenal glands. Gas chromatography-mass spectrometry (GC-MS) of urinary steroid metabolites has sensitivity and specificity of 90% for diagnosing adrenocortical carcinoma. Adrenal oncocytoma are rare tumours. Differentiating between benign and malignant types is difficult. Data guiding prognostication and management are sparse.
- Published
- 2019
76. Sodium-glucose cotransporter 2 inhibitors for type 2 diabetes-cardiovascular and renal benefits in patients with chronic kidney disease
- Author
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Tamara Y, Milder, Sophie L, Stocker, Dorit, Samocha-Bonet, Richard O, Day, and Jerry R, Greenfield
- Subjects
Glucose ,Diabetes Mellitus, Type 2 ,Cardiovascular Diseases ,Humans ,Renal Insufficiency, Chronic ,Kidney ,Sodium-Glucose Transporter 2 Inhibitors - Abstract
Sodium-glucose cotransporter 2 (SGLT2) inhibitors have important cardiovascular and renal benefits in adults with type 2 diabetes who have or are at high risk of cardiovascular and renal disease. These benefits are seen in patients with impaired renal function where the glucose-lowering effects are not observed. Here, we review the pharmacokinetics and pharmacology of SGLT2 inhibitors in relation to cardiovascular and renal outcomes in patients with chronic kidney disease (CKD).We searched PubMed and EMBASE for original research, meta-analyses and review articles relevant to the pharmacokinetics, and cardiac and renal outcomes of SGLT2 inhibitors published up until June 2019. Specialist society guidelines and publications were also consulted.Renal impairment is currently a contraindication to SGLT2 inhibitor use largely due to limited anti-hyperglycaemic efficacy. However, in cardiovascular outcome trials, and a dedicated renal outcome trial, cardiovascular and renal benefits were seen in participants with CKD suggesting that mechanisms underlying the cardiovascular and renal benefits of SGLT2 inhibitors are likely largely independent of the glucose-lowering action of these agents.Despite minimal glycaemic benefits in patients with type 2 diabetes and stage 3 CKD, the cardiovascular and renal benefits of these agents are preserved in this group of patients. Whether these agents have cardiovascular and renal benefits in patients with stage 4 CKD and patients with non-diabetic CKD needs further research.
- Published
- 2019
77. Longitudinal Changes in Insulin Resistance in Normal Weight, Overweight and Obese Individuals
- Author
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Dorit Samocha-Bonet, Jackson C. Blythe, Louise Purtell, Jerry R. Greenfield, Katherine T. Tonks, Jialiang Zhang, Nicholas Pocock, Donald J. Chisholm, Nathan A. Johnson, Adelle C.F. Coster, Alice Tang, Aimin Xu, Leonie K. Heilbronn, and Matthew Govendir
- Subjects
medicine.medical_specialty ,obesity ,lcsh:Medicine ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,Overweight ,Article ,03 medical and health sciences ,0302 clinical medicine ,Insulin resistance ,Internal medicine ,insulin resistance ,Liver fat ,medicine ,hyperinsulinaemic-euglycaemic clamp ,business.industry ,Fatty liver ,lcsh:R ,General Medicine ,liver fat ,medicine.disease ,Obesity ,fat-free mass ,Endocrinology ,Blood pressure ,Cohort ,medicine.symptom ,business ,Body mass index - Abstract
Background: Large cohort longitudinal studies have almost unanimously concluded that metabolic health in obesity is a transient phenomenon, diminishing in older age. We aimed to assess the fate of insulin sensitivity per se over time in overweight and obese individuals. Methods: Individuals studied using the hyperinsulinaemic-euglycaemic clamp at the Garvan Institute of Medical Research from 2008 to 2010 (n = 99) were retrospectively grouped into Lean (body mass index (BMI) <, 25 kg/m2) or overweight/obese (BMI &ge, 25 kg/m2), with the latter further divided into insulin-sensitive (ObSen) or insulin-resistant (ObRes), based on median clamp M-value (M/I, separate cut-offs for men and women). Fifty-seven individuals participated in a follow-up study after 5.4 ±, 0.1 years. Hyperinsulinaemic-euglycaemic clamp, dual-energy X-ray absorptiometry and circulating cardiovascular markers were measured again at follow-up, using the same protocols used at baseline. Liver fat was measured using computed tomography at baseline and proton magnetic resonance spectroscopy at follow-up with established cut-offs applied for defining fatty liver. Results: In the whole cohort, M/I did not change over time (p = 0.40), it remained significantly higher at follow-up in ObSen compared with ObRes (p = 0.02), and was not different between ObSen and Lean (p = 0.41). While BMI did not change over time (p = 0.24), android and visceral fat increased significantly in this cohort (ptime &le, 0.0013), driven by ObRes (p = 0.0087 and p = 0.0001, respectively). Similarly, systolic blood pressure increased significantly over time (ptime = 0.0003) driven by ObRes (p = 0.0039). The best correlate of follow-up M/I was baseline M/I (Spearman&rsquo, s r = 0.76, p = 1.1 ×, 10&minus, 7). Conclusions: The similarity in insulin sensitivity between the ObSen and the Lean groups at baseline persisted over time. Insulin resistance in overweight and obese individuals predisposed to further metabolic deterioration over time.
- Published
- 2019
78. Author reply
- Author
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Joanne E. Taylor, Lesley V. Campbell, and Jerry R. Greenfield
- Subjects
Inpatients ,Internal Medicine ,Diabetes Mellitus ,Prevalence ,Humans ,Insulin ,Medication Errors - Published
- 2019
79. Combination Therapy with an SGLT2 Inhibitor as Initial Treatment for Type 2 Diabetes: A Systematic Review and Meta-Analysis
- Author
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Lucy McGrath-Cadell, Dorit Samocha-Bonet, Tamara Y. Milder, Christina Abdel Shaheed, Richard O. Day, Sophie L. Stocker, and Jerry R. Greenfield
- Subjects
medicine.medical_specialty ,Combination therapy ,lcsh:Medicine ,030209 endocrinology & metabolism ,Type 2 diabetes ,Review ,Cochrane Library ,Gastroenterology ,03 medical and health sciences ,pharmacotherapy ,0302 clinical medicine ,Pharmacotherapy ,Weight loss ,Internal medicine ,DPP-4 inhibitors ,Medicine ,030212 general & internal medicine ,business.industry ,lcsh:R ,General Medicine ,medicine.disease ,Metformin ,Relative risk ,type 2 diabetes ,clinical pharmacology ,SGLT2 Inhibitor ,medicine.symptom ,business ,metformin ,SGLT2 inhibitors ,medicine.drug - Abstract
Background: Guidelines differ with regard to indications for initial combination pharmacotherapy for type 2 diabetes. Aims: To compare the efficacy and safety of (i) sodium-glucose cotransporter 2 (SGLT2) inhibitor combination therapy in treatment-naïve type 2 diabetes adults; (ii) initial high and low dose SGLT2 inhibitor combination therapy. Methods: PubMed, Embase and Cochrane Library were searched for randomised controlled trials (RCTs) of initial SGLT2 combination therapy. Mean difference (MD) for changes from baseline (HbA1c, weight, blood pressure) after 24–26 weeks of treatment and relative risks (RR, safety) were calculated using a random-effects model. Risk of bias and quality of evidence was assessed. Results: In 4 RCTs (n = 3749) there was moderate quality evidence that SGLT2 inhibitor/metformin combination therapy resulted in a greater reduction in HbA1c (MD (95% CI); −0.55% (−0.67, −0.43)) and weight (−2.00 kg (−2.34, −1.66)) compared with metformin monotherapy, and a greater reduction in HbA1c (−0.59% (−0.72, −0.46)) and weight (−0.57 kg (−0.89, −0.25)) compared with SGLT2 inhibitor monotherapy. The high dose SGLT2 inhibitor/metformin combination resulted in a similar HbA1c but greater weight reduction; −0.47 kg (−0.88, −0.06) than the low dose combination therapy. The RR of genital infection with combination therapy was 2.22 (95% CI 1.33, 3.72) and 0.69 (95% CI 0.50, 0.96) compared with metformin and SGLT2 inhibitor monotherapy, respectively. The RR of diarrhoea was 2.23 (95% CI 1.46, 3.40) with combination therapy compared with SGLT2 inhibitor monotherapy. Conclusions: Initial SGLT2 inhibitor/metformin combination therapy has glycaemic and weight benefits compared with either agent alone and appears relatively safe. High dose SGLT2 inhibitor/metformin combination therapy appears to have modest weight, but no glycaemic benefits compared with the low dose combination therapy.
- Published
- 2018
80. Fibroblast growth factor-1 (FGF-1) promotes adipogenesis by downregulation of carboxypeptidase A4 (CPA4) – a negative regulator of adipogenesis implicated in the modulation of local and systemic insulin sensitivity
- Author
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Daniel L. T Chen, Jerry R. Greenfield, Gongshe Yang, Johanna L. Barclay, Andrew C. Perkins, Graham Magor, Kevin R. Gillinder, Dorit Samocha-Bonet, Jingjing He, and Jonathan P. Whitehead
- Subjects
Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Carboxypeptidases A ,Clinical Biochemistry ,Down-Regulation ,Adipose tissue ,Biology ,Fibroblast growth factor ,03 medical and health sciences ,Endocrinology ,Downregulation and upregulation ,Internal medicine ,Adipocytes ,medicine ,Humans ,C741 Medical Biochemistry ,Muscle, Skeletal ,Cells, Cultured ,Carboxypeptidase A4 ,Gene knockdown ,Adipogenesis ,C130 Cell Biology ,Membrane Proteins ,Cell Biology ,Middle Aged ,Carboxypeptidase ,Cell biology ,PPAR gamma ,030104 developmental biology ,Liver ,biology.protein ,Fibroblast Growth Factor 1 ,BAMBI ,Insulin Resistance - Abstract
Fibroblast growth factor-1 (FGF-1) promotes differentiation of human preadipocytes into mature adipocytes via modulation of a BMP and Activin Membrane-Bound Inhibitor (BAMBI)/Peroxisome proliferator-activated receptor (PPARγ)-dependent network. Here, we combined transcriptomic and functional investigations to identify novel downstream effectors aligned with complementary analyses of gene expression in human adipose tissue to explore relationships with insulin sensitivity. RNA-Seq and qRT-PCR analysis revealed significant down-regulation of carboxypeptidase A4 (CPA4) following FGF-1 treatment or induction of differentiation of human preadipocytes in a BAMBI/PPARγ-independent manner. siRNA-mediated knockdown of CPA4 resulted in enhanced differentiation of human preadipocytes. Furthermore, expression of CPA4 in subcutaneous adipose tissue correlated negatively with indices of local and systemic (liver and muscle) insulin sensitivity. These results identify CPA4 as a negative regulator of adipogenesis that is down-regulated by FGF-1 and a putative deleterious modulator of local and systemic insulin sensitivity. Further investigations are required to define the molecular mechanism(s) involved and potential therapeutic opportunities.
- Published
- 2016
81. Dietary acid load, metabolic acidosis and insulin resistance – Lessons from cross-sectional and overfeeding studies in humans
- Author
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Daniel L. T Chen, Adelle C.F. Coster, Jerry R. Greenfield, Leonie K. Heilbronn, Dorit Samocha-Bonet, and Rebecca S. Williams
- Subjects
Adult ,Blood Glucose ,Male ,0301 basic medicine ,medicine.medical_specialty ,Diabetes risk ,medicine.medical_treatment ,030209 endocrinology & metabolism ,Type 2 diabetes ,Hyperphagia ,Overweight ,Critical Care and Intensive Care Medicine ,Body Mass Index ,03 medical and health sciences ,0302 clinical medicine ,Insulin resistance ,Internal medicine ,medicine ,Humans ,Insulin ,Lactic Acid ,Adiposity ,Acidosis ,030109 nutrition & dietetics ,Nutrition and Dietetics ,business.industry ,Metabolic acidosis ,Glucose clamp technique ,medicine.disease ,Diet Records ,Cross-Sectional Studies ,Endocrinology ,Diabetes Mellitus, Type 2 ,Diet, Western ,Glucose Clamp Technique ,Female ,Insulin Resistance ,medicine.symptom ,business ,Acids ,Biomarkers - Abstract
Summary Background & aim Western diets rich in animal protein and poor in fruit and vegetables increase the body acid load, a predictor of type 2 diabetes risk. The relationships between dietary acid load, mild metabolic acidosis and insulin resistance remain unclear. The objective of this study was to assess the association between dietary acid load, body acid/base markers and peripheral insulin resistance at baseline and following a short-term overfeeding intervention in healthy individuals. Methods In a cross-sectional study of 104 men and women, insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp. Plasma lactate, a marker of metabolic acidosis, was assessed and acid load scores (potential renal acid load, PRAL and net endogenous acid production, NEAP) derived from diet diaries. The cohort was grouped into lean and overweight/obese and the latter further classified as insulin-sensitive (Obsen) and insulin-resistant (Obres) based on hyperinsulinemic-euglycemic clamp glucose infusion rate (GIR, top tertile vs. bottom 2 tertiles). A subset of 40 individuals participated in an overfeeding intervention (+1250 kcal/day) for 28 days and studies repeated. Results Obsen and Obres were matched for adiposity (BMI and fat mass, both P = 1). Fasting plasma lactate was higher in Obres (0.78 [0.63–1.14] mmol/L) compared with both lean (0.71 [0.44–0.90] mmol/L, P = 0.02) and Obsen (0.67 [0.56–0.79] mmol/L, P = 0.04) and not different between lean and Obsen (P = 0.9). Overfeeding was characterized by an increase in dietary acid load scores PRAL (P = 0.003) and NEAP (P = 0.05), a reduction in GIR necessary to maintain euglycemia (P = 0.03) and an increase in fasting plasma lactate (P = 0.02). The change in lactate was inversely associated with the change in GIR (r = −0.36, P = 0.03). Conclusions Mild metabolic acidosis, measured by plasma lactate, aligns with insulin resistance independent of obesity and is induced by short-term increases in energy and dietary acid load in healthy humans. Further studies are required to determine whether buffering mild metabolic acidosis improves insulin resistance and reduces diabetes risk.
- Published
- 2016
82. Temporal HbA1c patterns amongst patients with type 2 diabetes referred for specialist care: Data from the S4S-DINGO-Diabetes Informatics Group
- Author
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David M. Hoffman, Tien-Ming Hng, Jerry R. Greenfield, Natalie Harrison, David Darnell, N. Wah Cheung, Anthony F. Morrow, Kimberly Cukier, and Teresa Lam
- Subjects
Male ,medicine.medical_specialty ,Referral ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Type 2 diabetes ,Audit ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,biology.animal ,Diabetes mellitus ,Internal Medicine ,Humans ,Medicine ,030212 general & internal medicine ,Glycated Hemoglobin ,Medical Audit ,biology ,business.industry ,Type 2 Diabetes Mellitus ,General Medicine ,Middle Aged ,medicine.disease ,Diabetes Mellitus, Type 2 ,Private practice ,Informatics ,Family medicine ,Female ,Dingo ,business - Abstract
To evaluate the achievement of HbA1c targets in patients with type 2 diabetes mellitus in specialist practice.This audit was undertaken by members of the S4S Diabetes Informatics Group (DINGO), a consortium of Australian endocrinologists in private practice who contribute de-identified data from their electronic medical record, Audit 4 (Software 4 Specialists, S4S, AustraliaNew Zealand) for audit purposes. Data from patients with type 2 diabetes was extracted. Inclusion criteria were: initial age70years, baseline HbA1c7% (53mmol/mol), with at least another HbA1c recorded in the next 2years, and a minimum of 2years follow-up. Data was analysed using a linear mixed effects model.Of the 4796 patients in the dataset with type 2 diabetes mellitus, 1379 patients fulfilled inclusion criteria. The median age at initial consultation was 57 (49-64)years. The median baseline HbA1c was 8.7 (7.8-9.8)% (72mmol/mol). There was a 1.0% reduction in HbA1c to 7.7 (7.1-8.6)% (61mmol/mol) (p0.0001) in the first 3-6months following referral, after which there were no further changes. The initial reduction was maintained with minimal loss of control at 4years. By 3-6months, 24% of patients achieved the target HbA1c.Referral of patients with type 2 diabetes to an endocrinologist reduces HbA1c, and the effect is sustained over the medium term; however only a minority of patients reach targets.
- Published
- 2016
83. Brown Adipose Tissue Exhibits a Glucose-Responsive Thermogenic Biorhythm in Humans
- Author
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Louise Emmett, Lynne Schofield, Jerry R. Greenfield, Matt A. Govendir, William Dieckmann, Wendy Bryant, Paul Lee, Ron Bova, and Anthony Slattery
- Subjects
Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,animal structures ,Physiology ,Population ,Biorhythm ,030209 endocrinology & metabolism ,Glucose responsive ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Adipose Tissue, Brown ,Internal medicine ,Diabetes mellitus ,Brown adipose tissue ,medicine ,Humans ,Glucose homeostasis ,Circadian rhythm ,education ,Molecular Biology ,Cells, Cultured ,Uncoupling Protein 1 ,education.field_of_study ,Glucose Transporter Type 4 ,biology ,Thermogenesis ,Cell Biology ,Middle Aged ,medicine.disease ,Circadian Rhythm ,Adipocytes, Brown ,Glucose ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Nuclear Receptor Subfamily 1, Group D, Member 1 ,biology.protein ,Female ,GLUT4 - Abstract
High abundance of brown adipose tissue (BAT) is linked to lower glycaemia in humans, leading to the belief that BAT may protect against diabetes. The relationship between BAT glucose utilization and systemic glucose homeostasis has not been defined. In this paper we have characterized glycaemic excursions and BAT thermogenic responses in human brown adipocytes, BAT explants, and healthy adults through supraclavicular temperature profiling, revealing their circadian coupling in vivo and in vitro, orchestrated by UCP1, GLUT4, and Rev-erbα biorhythms. Extent of glycated haemoglobin also correlated positively with environmental temperature among community-dwelling patients. These data uncover potential crosstalk between BAT and glucose regulatory pathways, evident on cellular, tissue, individual, and population levels, and provide impetus to search for BAT harnessing strategies for therapeutic purposes.
- Published
- 2016
84. Synchronous Nesidioblastosis, Endocrine Microadenoma, and Intraductal Papillary Mucinous Neoplasia in a Man Presenting With Hyperinsulinemic Hypoglycemia
- Author
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Jerry R. Greenfield, Daniel L. T Chen, Min Ru Qiu, Sunita M C De Sousa, and Koroush S. Haghighi
- Subjects
Adenoma ,Adult ,Blood Glucose ,Male ,medicine.medical_specialty ,Pathology ,Time Factors ,Pancreatic disease ,Biopsy ,Endocrinology, Diabetes and Metabolism ,Nesidioblastosis ,Neuroendocrine tumors ,Hypoglycemia ,medicine.disease_cause ,Diagnosis, Differential ,Neoplasms, Multiple Primary ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Predictive Value of Tests ,Risk Factors ,Hyperinsulinism ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Insulin ,Endocrine system ,Hyperinsulinemic hypoglycemia ,Hepatology ,business.industry ,Hyperplasia ,medicine.disease ,Immunohistochemistry ,Pancreatic Neoplasms ,Neuroendocrine Tumors ,Pancreatic Function Tests ,Treatment Outcome ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Neoplasms, Cystic, Mucinous, and Serous ,Tomography, X-Ray Computed ,business ,Pancreas - Abstract
Herein, we report the first case of concomitant nesidioblastosis, pancreatic neuroendocrine tumor, and intraductal papillary mucinous neoplasia. The combination is significant as each of these pathological entities is independently very rare. The patient was a 33-year-old man who presented with symptomatic hyperinsulinemic hypoglycemia and no risk factors for pancreatic disease. Abdominal imaging showed an isolated 12 mm pancreatic lesion, whilst selective arterial calcium stimulation testing demonstrated multiple territories of insulin excess. He proceeded to subtotal pancreatectomy. Histopathology revealed an endocrine microadenoma, α and β cell nesidioblastosis, and multifocal intraductal papillary mucinous neoplasia. The endocrine microadenoma and nesidioblastosis stained for insulin, suggesting both likely contributed to hypoglycemia. Glucagon immunohistochemistry was also positive, though there were no clinical features of glucagon excess. Hypoglycemia resolved postoperatively. This case and other evidence from the literature suggest that hyperplasia and neoplasia may occur sequentially in the pancreas, and that endocrine and exocrine tumorigenesis may be linked in some individuals. Further study is required to identify a unifying mechanism, and to elucidate potential ramifications in the management of patients with pancreatic neoplasms.
- Published
- 2016
85. Non-pharmacological and pharmacological strategies of brown adipose tissue recruitment in humans
- Author
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Jerry R. Greenfield and Paul Lee
- Subjects
medicine.medical_specialty ,animal structures ,FGF21 ,Bioenergetics ,Pituitary-Adrenal System ,Adipose tissue ,White adipose tissue ,Biology ,Biochemistry ,Endocrinology ,Adipose Tissue, Brown ,Internal medicine ,Weight Loss ,Brown adipose tissue ,medicine ,Humans ,Molecular Biology ,Thermogenesis ,Fibronectins ,Fibroblast Growth Factors ,medicine.anatomical_structure ,Anti-Obesity Agents ,Energy Metabolism ,Homeostasis ,Hormone - Abstract
Humans maintain core temperature through a complex neuroendocrine circuitry, coupling environmental thermal and nutritional cues to heat-producing and dissipating mechanisms. Up to 40% of resting energy expenditure contributes to thermal homeostasis maintenance. Recent re-discovery of thermogenic brown adipose tissue (BAT) has brought the relation between ambient temperature, thermogenesis and systemic energy and substrate metabolism to the forefront. In addition to well-known pituitary-thyroid-adrenal axis, new endocrine signals, such as FGF21 and irisin, orchestrate crosstalk between white adipose tissue (WAT), BAT and muscle, tuning non-shivering and shivering thermogenesis responses. Cold exposure modulates the endocrine milieu, and cold-induced hormones cause bioenergetics transformation sufficient to impact whole body metabolism. This review will appraise the nature of human BAT and the basis of BAT-centred therapeutics, highlighting how the interaction between hormones and adipose tissue impacts metabolic responses. Non-pharmacological and pharmacological strategies of BAT recruitment and/or fat browning for metabolic benefits will be discussed.
- Published
- 2015
86. Empagliflozin in the management of diabetes mellitus after cardiac transplantation
- Author
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Peter S. Macdonald, Jerry R. Greenfield, and Christopher A. Muir
- Subjects
Pulmonary and Respiratory Medicine ,Transplantation ,medicine.medical_specialty ,business.industry ,030204 cardiovascular system & hematology ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Diabetes mellitus ,medicine ,Empagliflozin ,Surgery ,030212 general & internal medicine ,Cardiology and Cardiovascular Medicine ,Intensive care medicine ,business - Published
- 2017
87. 1133 PANCREATIC STELLATE CELL AND CANCER CELL DERIVED EXOSOMES IMPAIR BETA CELL FUNCTION: IMPLICATIONS FOR PANCREATIC CANCER RELATED DIABETES
- Author
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Alpha Raj Mekapogu, Jerry R. Greenfield, S. M. Zahid Hosen, David Goldstein, Romano C. Pirola, Jeremy S. Wilson, Minoti V. Apte, Chamini J. Perera, Srinivasa Pothula, Zhihong Xu, and Suresh T. Chari
- Subjects
Hepatology ,business.industry ,Gastroenterology ,Pancreatic stellate cell ,Beta-cell Function ,medicine.disease ,Microvesicles ,medicine.anatomical_structure ,Pancreatic cancer ,Diabetes mellitus ,Cancer cell ,medicine ,Cancer research ,business - Published
- 2020
88. Paul Lee, 1977-2017
- Author
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Jerry R, Greenfield and Paul, Lee
- Subjects
Endocrinology ,Physicians ,Medical Laboratory Personnel ,Humans ,History, 20th Century ,History, 21st Century - Published
- 2018
89. Mitochondrial CoQ deficiency is a common driver of mitochondrial oxidants and insulin resistance
- Author
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Kyle L. Hoehn, Jerry R. Greenfield, Warren Kaplan, Ganesh Kolumam, James G. Burchfield, David E. James, Nolan J. Hoffman, Daniel L. T Chen, Jean Yh Yang, Ciana Diskin, Kelsey H. Fisher-Wellman, Sean J. Humphrey, Ghassan J. Maghzal, Kristen C. Thomas, Benjamin L. Parker, James R. Krycer, Zora Modrusan, Rima Chaudhuri, Roland Stocker, Daniel J. Fazakerley, Pengyi Yang, Dorit Samocha-Bonet, Christopher C. Meoli, Mark J. Cowley, Fazakerley, Daniel J [0000-0001-8241-2903], James, David E [0000-0001-5946-5257], and Apollo - University of Cambridge Repository
- Subjects
0301 basic medicine ,Mitochondrial Diseases ,Mouse ,Ubiquinone ,medicine.medical_treatment ,Respiratory chain ,Adipose tissue ,Mitochondrion ,Mice ,chemistry.chemical_compound ,Adipocytes ,Insulin ,Glucose homeostasis ,Biology (General) ,Muscle Weakness ,Chemistry ,Superoxide ,Muscles ,General Neuroscience ,human biology ,food and beverages ,General Medicine ,Oxidants ,Mitochondria ,3. Good health ,Adipose Tissue ,Medicine ,Research Article ,Human ,medicine.medical_specialty ,QH301-705.5 ,Science ,Sensitivity and Specificity ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Insulin resistance ,Internal medicine ,medicine ,Animals ,Humans ,Human Biology and Medicine ,General Immunology and Microbiology ,Coenzyme Q ,Cell Biology ,medicine.disease ,030104 developmental biology ,Endocrinology ,Coenzyme Q – cytochrome c reductase ,Ataxia - Abstract
Insulin resistance in muscle, adipocytes and liver is a gateway to a number of metabolic diseases. Here, we show a selective deficiency in mitochondrial coenzyme Q (CoQ) in insulin-resistant adipose and muscle tissue. This defect was observed in a range of in vitro insulin resistance models and adipose tissue from insulin-resistant humans and was concomitant with lower expression of mevalonate/CoQ biosynthesis pathway proteins in most models. Pharmacologic or genetic manipulations that decreased mitochondrial CoQ triggered mitochondrial oxidants and insulin resistance while CoQ supplementation in either insulin-resistant cell models or mice restored normal insulin sensitivity. Specifically, lowering of mitochondrial CoQ caused insulin resistance in adipocytes as a result of increased superoxide/hydrogen peroxide production via complex II. These data suggest that mitochondrial CoQ is a proximal driver of mitochondrial oxidants and insulin resistance, and that mechanisms that restore mitochondrial CoQ may be effective therapeutic targets for treating insulin resistance., eLife digest After we eat, our blood sugar levels increase. To counteract this, the pancreas releases a hormone called insulin. Part of insulin’s effect is to promote the uptake of sugar from the blood into muscle and fat tissue for storage. Under certain conditions, such as obesity, this process can become defective, leading to a condition known as insulin resistance. This condition makes a number of human diseases more likely to develop, including type 2 diabetes. Working out how insulin resistance develops could therefore unveil new treatment strategies for these diseases. Mitochondria – structures that produce most of a cell’s energy supply – appear to play a role in the development of insulin resistance. Mitochondria convert nutrients such as fats and sugars into molecules called ATP that fuel the many processes required for life. However, ATP production can also generate potentially harmful intermediates often referred to as ‘reactive oxygen species’ or ‘oxidants’. Previous studies have suggested that an increase in the amount of oxidants produced in mitochondria can cause insulin resistance. Fazakerley et al. therefore set out to identify the reason for increased oxidants in mitochondria, and did so by analysing the levels of proteins and oxidants found in cells grown in the laboratory, and mouse and human tissue samples. This led them to find that concentrations of a molecule called coenzyme Q (CoQ), an essential component of mitochondria that helps to produce ATP, were lower in mitochondria from insulin-resistant fat and muscle tissue. Further experiments suggested a link between the lower levels of CoQ and the higher levels of oxidants in the mitochondria. Replenishing the mitochondria of the lab-grown cells and insulin-resistant mice with CoQ restored ‘normal’ oxidant levels and prevented the development of insulin resistance. Strategies that aim to increase mitochondria CoQ levels may therefore prevent or reverse insulin resistance. Although CoQ supplements are readily available, swallowing CoQ does not efficiently deliver CoQ to mitochondria in humans, so alternative treatment methods must be found. It is also of interest that statins, common drugs taken by millions of people around the world to lower cholesterol, also lower CoQ and have been reported to increase the risk of developing type 2 diabetes. Further research is therefore needed to investigate whether CoQ might provide the link between statins and type 2 diabetes.
- Published
- 2018
90. Effects of glutamine on gastric emptying of low- and high-nutrient drinks in healthy young subjects-impact on glycaemia
- Author
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Karen L. Jones, Christopher K. Rayner, Dorit Samocha-Bonet, Jerry R. Greenfield, Michael Horowitz, Yang T Du, Saima Ahmad, Diana Piscitelli, Laurence G. Trahair, Du, Yang T, Piscitelli, Diana, Ahmad, Saima, Trahair, Laurence G, Greenfield, Jerry R, Samocha-Bonet, Dorit, Rayner, Christopher K, Horowitz, Michael, and Jones, Karen L
- Subjects
Blood Glucose ,Male ,insulin ,medicine.medical_specialty ,Time Factors ,Glutamine ,medicine.medical_treatment ,Administration, Oral ,Blood sugar ,lcsh:TX341-641 ,postprandial ,030209 endocrinology & metabolism ,Article ,Young Adult ,03 medical and health sciences ,gastric emptying ,0302 clinical medicine ,Double-Blind Method ,Internal medicine ,South Australia ,Blood plasma ,medicine ,Energy Drinks ,Humans ,030212 general & internal medicine ,glucose ,glutamine ,glycaemia ,Cross-Over Studies ,Nutrition and Dietetics ,Gastric emptying ,Chemistry ,Insulin ,Age Factors ,Crossover study ,Healthy Volunteers ,Endocrinology ,Postprandial ,Blood chemistry ,Dietary Supplements ,lcsh:Nutrition. Foods and food supply ,Nutritive Value ,Biomarkers ,Food Science - Abstract
Glutamine is a potent stimulus for the release of glucagon-like peptide-1, which increases postprandial insulin and slows gastric emptying (GE). We determined the effects of glutamine on GE of, and glycaemic responses to, low- and high-nutrient drinks in eight healthy males (mean age 21.6 ±, 0.7 years and BMI 22.9 ±, 0.7 kg/m2). Participants were studied on four occasions on which they consumed either a low-nutrient (beef soup, 18 kcal) or high-nutrient (75 g dextrose, 255 kcal) drink, each with or without 30 g of glutamine (120 kcal), in a randomised, crossover design. GE (2D ultrasound), blood glucose and plasma insulin concentrations were measured concurrently. Glutamine slowed GE (half emptying time (T50)) of both low- (45 ±, 3 min vs. 26 ±, 2 min, p <, 0.001), and high-nutrient, (100 ±, 5 min vs. 77 ±, 5 min, p = 0.03) drinks, however, there was no effect on GE of the high nutrient drinks when expressed as kcal/min (3.39 ±, 0.21 kcal/min vs. 3.81 ±, 0.20 kcal/min, p = 0.25). There was no change in blood glucose after the low-nutrient drinks with or without glutamine, despite a slight increase in plasma insulin with glutamine (p = 0.007). The rise in blood glucose following the high-nutrient drink (p = 0.0001) was attenuated during the first 60 min by glutamine (p = 0.007). We conclude that in healthy subjects, glutamine slows GE of both low- and high-nutrient drinks comparably and attenuates the rise in blood glucose after the high-nutrient glucose drink.
- Published
- 2018
91. Comment on Braffett et al. Association of Insulin Dose, Cardiometabolic Risk Factors, and Cardiovascular Disease in Type 1 Diabetes During 30 Years of Follow-up in the DCCT/EDIC Study. Diabetes Care 2019;42:657–664
- Author
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Jennifer R Snaith, D. J. Holmes-Walker, and Jerry R. Greenfield
- Subjects
Advanced and Specialized Nursing ,Cardiometabolic risk ,Type 1 diabetes ,medicine.medical_specialty ,Pediatrics ,endocrine system diseases ,business.industry ,Endocrinology, Diabetes and Metabolism ,Insulin ,medicine.medical_treatment ,030209 endocrinology & metabolism ,Disease ,medicine.disease ,Insulin dose ,03 medical and health sciences ,0302 clinical medicine ,Diabetes mellitus ,Epidemiology ,Internal Medicine ,medicine ,030212 general & internal medicine ,medicine.symptom ,business ,Weight gain - Abstract
We read with great interest that Braffett et al. (1) report an association between insulin dose and adverse cardiometabolic profiles using 30 years of follow-up data from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study. Intensive diabetes treatment necessitating increased insulin doses became the accepted standard of care in type 1 diabetes after the DCCT/EDIC trial demonstrated cardiovascular risk benefit (mean ± SD 0.71 ± 0.21 vs. 0.65 ± 0.21 units/kg/day in the intensive vs. conventional treatment group; P = 0.0001). We support the authors’ emphasis that this association is somewhat driven by insulin-related weight gain, especially in males. The report …
- Published
- 2019
92. Novel circulating biomarkers identify insulin resistance phenotypes in obesity
- Author
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Jerry R. Greenfield, Arthur B. Jenkins, Pengyi Yang, Dorit Samocha-Bonet, Yen Chin Koay, Daniel Chen, and John F. O'Sullvan
- Subjects
Circulating biomarkers ,Nutrition and Dietetics ,Insulin resistance ,business.industry ,Endocrinology, Diabetes and Metabolism ,Immunology ,medicine ,medicine.disease ,business ,Obesity ,Phenotype - Published
- 2019
93. Excess mortality and cardiovascular disease risk in type 1 diabetes
- Author
-
Christian M. Girgis, Jerry R. Greenfield, Jennifer R Snaith, and D. J. Holmes-Walker
- Subjects
Excess mortality ,medicine.medical_specialty ,Type 1 diabetes ,business.industry ,General Medicine ,medicine.disease ,Cohort Studies ,Young Adult ,Diabetes Mellitus, Type 1 ,Diabetes Mellitus, Type 2 ,Cardiovascular Diseases ,Internal medicine ,Disease risk ,medicine ,Humans ,Age of Onset ,business - Published
- 2019
94. Circulating bile acids are associated with insulin resistance and visceral and liver fat in human subjects
- Author
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Dorit Samocha-Bonet, Katherine T. Tonks, Donald J. Chisholm, Ramy H Bishay, Jerry R. Greenfield, Jacob George, and David E. James
- Subjects
medicine.medical_specialty ,Nutrition and Dietetics ,Insulin resistance ,Endocrinology ,business.industry ,Endocrinology, Diabetes and Metabolism ,Internal medicine ,Liver fat ,Medicine ,business ,medicine.disease - Published
- 2019
95. Author response: Mitochondrial CoQ deficiency is a common driver of mitochondrial oxidants and insulin resistance
- Author
-
Daniel J Fazakerley, Rima Chaudhuri, Pengyi Yang, Ghassan J Maghzal, Kristen C Thomas, James R Krycer, Sean J Humphrey, Benjamin L Parker, Kelsey H Fisher-Wellman, Christopher C Meoli, Nolan J Hoffman, Ciana Diskin, James G Burchfield, Mark J Cowley, Warren Kaplan, Zora Modrusan, Ganesh Kolumam, Jean YH Yang, Daniel L Chen, Dorit Samocha-Bonet, Jerry R Greenfield, Kyle L Hoehn, Roland Stocker, and David E James
- Published
- 2017
96. Phenotypic Characterization of Insulin-Resistant and Insulin-Sensitive Obesity
- Author
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Dorit Samocha-Bonet, Anne Poljak, Donald J. Chisholm, Jerry R. Greenfield, Carsten Liess, Christian Thoma, Aimin Xu, Arthur B. Jenkins, B Milner, Jialiang Zhang, Daniel L. T Chen, and Michael I. Trenell
- Subjects
Adult ,Male ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,Subcutaneous Fat ,Blood Pressure ,Context (language use) ,Biochemistry ,Body Mass Index ,Young Adult ,chemistry.chemical_compound ,Endocrinology ,Insulin resistance ,Hyperinsulinism ,Internal medicine ,Adipocytes ,medicine ,Humans ,Obesity ,Pancreas ,Triglycerides ,Aged ,Cholesterol ,business.industry ,Muscles ,Insulin ,Cholesterol, HDL ,Biochemistry (medical) ,Middle Aged ,Glucose clamp technique ,medicine.disease ,C-Reactive Protein ,Phenotype ,Liver ,chemistry ,Glucose Clamp Technique ,Female ,Glycated hemoglobin ,Insulin Resistance ,business ,Body mass index - Abstract
Context: Whereas insulin resistance and obesity coexist, some obese individuals remain insulin sensitive. Objective: We examined phenotypic and metabolic factors associated with insulin sensitivity in both muscle and liver in obese individuals. Design and Participants: Sixty-four nondiabetic obese adults (29 males) underwent hyperinsulinemic (15 and 80 mU/m2 · min)-euglycemic clamps with deuterated glucose. Top tertile subjects for glucose infusion rate during the high-dose insulin clamp were assigned Musclesen and those in the lower two tertiles were assigned Muscleres. Secondarily, top tertile subjects for endogenous glucose production suppression during the low-dose insulin clamp were deemed Liversen and the remainder Liverres. Main Outcomes Measures: Clinical and laboratory parameters and visceral, subcutaneous, liver, and pancreatic fat were compared. Results: Musclesen and Muscleres had similar body mass index and total fat (P > .16), but Musclesen had lower glycated hemoglobin (P < .001) and systolic (P = .01) and diastolic (P = .03) blood pressure (BP). Despite similar sc fat (P = 1), Musclesen had lower visceral (P < .001) and liver (P < .001) fat. Liversen had lower visceral (P < .01) and liver (P < .01) fat and C-reactive protein (P = .02) than Liverres. When subjects were grouped by both glucose infusion rate during the high-dose insulin clamp and endogenous glucose production suppression, insulin sensitivity at either muscle or liver conferred apparent protection from the adverse metabolic features that characterized subjects insulin resistant at both sites. High-density lipoprotein-cholesterol, 1-hour glucose, systolic BP, and triglycerides explained 54% of the variance in muscle insulin sensitivity. Conclusions: Obese subjects who were insulin sensitive at muscle and/or liver exhibited favorable metabolic features, including lower BP, liver and visceral adiposity. This study identifies factors associated with, and possibly contributing to, insulin sensitivity in obesity.
- Published
- 2015
97. L-Glutamine and Whole Protein Restore First-Phase Insulin Response and Increase Glucagon-Like Peptide-1 in Type 2 Diabetes Patients
- Author
-
Jerry R. Greenfield, Jens J. Holst, Donald J. Chisholm, and Dorit Samocha-Bonet
- Subjects
Adult ,Blood Glucose ,Male ,hyperglycemic glucose clamp ,medicine.medical_specialty ,Glutamine ,medicine.medical_treatment ,insulin response ,lcsh:TX341-641 ,030209 endocrinology & metabolism ,Complete protein ,Type 2 diabetes ,Glucagon ,Article ,03 medical and health sciences ,0302 clinical medicine ,Glucagon-Like Peptide 1 ,Internal medicine ,Diabetes mellitus ,Humans ,Insulin ,Medicine ,Aged ,030304 developmental biology ,0303 health sciences ,Cross-Over Studies ,Nutrition and Dietetics ,business.industry ,Middle Aged ,medicine.disease ,Glucagon-like peptide-1 ,3. Good health ,Postprandial ,Endocrinology ,Diabetes Mellitus, Type 2 ,Female ,type 2 diabetes ,Dietary Proteins ,business ,lcsh:Nutrition. Foods and food supply ,Food Science - Abstract
l-glutamine triggers glucagon-like peptide-1 (GLP-1) release from L cells in vitro and when ingested pre-meal, decreases postprandial glycaemia and increases circulating insulin and GLP-1 in type 2 diabetes (T2D) patients. We aimed to evaluate the effect of oral l-glutamine, compared with whole protein low in glutamine, on insulin response in well-controlled T2D patients. In a randomized study with a crossover design, T2D patients (n = 10, 6 men) aged 65.1 ± 5.8, with glycosylated hemoglobin (HbA1c) 6.6% ± 0.7% (48 ± 8 mmol/mol), received oral l-glutamine (25 g), protein (25 g) or water, followed by an intravenous glucose bolus (0.3 g/kg) and hyperglycemic glucose clamp for 2 h. Blood was frequently collected for analyses of glucose, serum insulin and plasma total and active GLP-1 and area under the curve of glucose, insulin, total and active GLP-1 excursions calculated. Treatments were tested 1–2 weeks apart. Both l-glutamine and protein increased first-phase insulin response (p ≤ 0.02). Protein (p = 0.05), but not l-glutamine (p = 0.2), increased second-phase insulin response. Total GLP-1 was increased by both l-glutamine and protein (p ≤ 0.02). We conclude that oral l-glutamine and whole protein are similarly effective in restoring first-phase insulin response in T2D patients. Larger studies are required to further investigate the utility of similar approaches in improving insulin response in diabetes.
- Published
- 2015
98. The pharmacokinetics of metformin and concentrations of haemoglobin A1Cand lactate in Indigenous and non-Indigenous Australians with type 2 diabetes mellitus
- Author
-
Carl M. J. Kirkpatrick, Jerry R. Greenfield, Timothy J. Furlong, Richard O. Day, Garry G. Graham, Kenneth M. Williams, Janna K. Duong, and Shaun S. Kumar
- Subjects
medicine.medical_specialty ,Renal function ,030226 pharmacology & pharmacy ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pharmacokinetics ,Interquartile range ,Internal medicine ,medicine ,Pharmacology (medical) ,030212 general & internal medicine ,Vitamin B12 ,Pharmacology ,Creatinine ,business.industry ,Type 2 Diabetes Mellitus ,medicine.disease ,3. Good health ,Metformin ,Endocrinology ,chemistry ,business ,medicine.drug ,Kidney disease - Abstract
Aims To compare the pharmacokinetics of metformin between diabetic Indigenous (Aboriginal and Torres Strait Islander) and non-Indigenous patients. Methods An observational, cross-sectional study was conducted on type 2 diabetic Indigenous and non-Indigenous patients treated with metformin. Blood samples were collected to determine metformin, lactate, creatinine and vitamin B12 concentrations and glycosylated haemoglobin levels. A population model was used to determine the pharmacokinetic parameters. Results The Indigenous patients (median age 55 years) were younger than the non-Indigenous patients (65 years), with a difference of 10 years (95% confidence interval 6–14 years, P < 0.001). The median glycosylated haemoglobin was higher in the Indigenous patients (8.5%) than in the non-Indigenous patients (7.2%), with a difference of 1.4% (0.8–2.2%, P < 0.001). Indigenous patients had a higher creatinine clearance (4.3 l h−1) than the non-Indigenous patients (4.0 l h−1), with a median difference of 0.3 l h−1 (0.07–1.17 l h−1; P < 0.05). The ratio of the apparent clearance of metformin to the creatinine clearance in Indigenous patients (13.1, 10.2–15.2; median, interquartile range) was comparable to that in non-Indigenous patients (12.6, 9.9–14.9). Median lactate concentrations were also similar [1.55 (1.20–1.88) vs. 1.60 (1.35–2.10) mmol l−1] for Indigenous and non-Indigenous patients, respectively. The median vitamin B12 was 306 pmol l−1 (range 105–920 pmol l−1) for the Indigenous patients. Conclusions There were no significant differences in the pharmacokinetics of metformin or plasma concentrations of lactate between Indigenous and non-Indigenous patients with type 2 diabetes mellitus. Further studies are required in Indigenous patients with creatinine clearance
- Published
- 2015
99. Ectopic Cushing syndrome due to neuroendocrine prostatic cancer
- Author
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Adrian Pokorny, Emily Stone, Jerry R. Greenfield, Richard J. Epstein, J. Shrosbree, and Ann McCormack
- Subjects
Oncology ,medicine.medical_specialty ,business.industry ,Cancer ,030209 endocrinology & metabolism ,medicine.disease ,03 medical and health sciences ,Cushing syndrome ,0302 clinical medicine ,Text mining ,030220 oncology & carcinogenesis ,Internal medicine ,Internal Medicine ,medicine ,business - Published
- 2016
100. High prevalence of diabetes before and after lung transplantation: target for improving outcome?
- Author
-
Monika, Fazekas-Lavu, Michael, Reyes, Monique, Malouf, Marshall, Plit, Adrian, Havryk, Lesley V, Campbell, Jacqueline R, Center, Allan R, Glanville, and Jerry R, Greenfield
- Subjects
Adult ,Blood Glucose ,Male ,Databases, Factual ,Waiting Lists ,Middle Aged ,Young Adult ,Treatment Outcome ,Diabetes Mellitus ,Prevalence ,Humans ,Female ,Prospective Studies ,Aged ,Lung Transplantation - Abstract
Diabetes increases morbidity and mortality of lung transplantation. However, the reported prevalence of diabetes varies post-transplantation partly due to lack of detection protocols.To determine the prevalence of diabetes in patients (i) waitlisted for lung transplant and (ii) early post-transplantation.We analysed patients on the St Vincent's Heart Lung database from 1 April 2014 to 30 September 2015 on the waitlist (Study 1) and those transplanted (Study 2). Standard of care required all non-diabetic patients to have an oral glucose tolerance test (modified for patients with cystic fibrosis (CF) to screen for CF-related hyperglycaemia (CFRH) (plasma glucose ≥8.2 mmol/L at 60 or 90 min).Study 1 included 114 patients (32 with CF and 82 without CF). Of 30 CF patients with glycaemic data, 27 (90%) had abnormal glucose metabolism: 18 had diabetes and nine had CFRH. In 50 patients without CF, 20 (40%) had abnormal glucose metabolism: eight had diabetes and 12 had impaired fasting glucose and/or impaired glucose tolerance. Study 2 included 78 transplanted patients (25 with CF and 53 without CF). Fourteen CF patients had pre-existing diabetes and seven had pre-existing CFRH. All but one patient were diagnosed with diabetes post-transplantation. Hence, diabetes prevalence in CF patients post-transplantation was 96%. Among 53 transplanted patients without CF, seven (13%) had abnormal glucose metabolism but 30 (57%) were diagnosed with post-transplant diabetes.There is a high prevalence of diabetes in lung transplant patients. Earlier endocrine participation in lung transplant services is likely to lower diabetes-related morbidity and mortality further.
- Published
- 2017
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