Postprandial Thermogenesis Is Reduced in Obesity

Background and Aims: Postprandial thermogenesis is thought to be important for the control of metabolism. This process could be reflected by minute changes in body temperature after glucose load. In this study, we measured body temperature before and its change during a glucose challenge and investigated the relationships with anthropometric and glycemic traits. Methods: We prospectively studied 383 volunteers (251 females, 132 males) with a mean age of 46.6 (SD ± 16) years and a BMI of 27.9 kg/m2 (SD ± 5.9). All participants underwent a 75 g oral glucose tolerance test (OGTT) and repeated bilateral measurements of intra-auricular temperature at time points 0, 30 and 120 minutes during the OGTT using a tympanic thermometer (Covidien Genius 2). Results: Baseline temperature was 0.17°C lower in males compared to females (p = 0.001) and inversely associated with age (p < 0.0001). During the OGTT, there was a significant increase in body temperature (0.18 ± 0.34°C). This response was present in females and males. BMI was negatively associated with the increase of temperature during the OGTT (p = 0.0147). Participants with higher BMI displayed higher fasting temperatures, but less increase of temperature during the OGTT. Body temperature was not associated with glycemia, insulin sensitivity or insulin secretion, neither in females nor males. Conclusions: There is a robust increase in body temperature during a glucose load that can be captured by intra-auricular temperature measurements. We did not detect any associations of the body temperature with glucose metabolism, arguing against a major contribution of the variability of body temperature in the pathogenesis of diabetes. However, the rise in temperature in response to oral glucose is reduced in obesity and might therefore be involved in body weight regulation.

Obesity and Impaired Metabolic Health Increase Risk of COVID-19-Related Mortality in Young and Middle-Aged Adults to the Level Observed in Older People: The LEOSS Registry.

Advanced age, followed by male sex, by far poses the greatest risk for severe COVID-19. An unresolved question is the extent to which modifiable comorbidities increase the risk of COVID-19-related mortality among younger patients, in whom COVID-19-related hospitalization strongly increased in 2021. A total of 3,163 patients with SARS-COV-2 diagnosis in the Lean European Open Survey on SARS-CoV-2-Infected Patients (LEOSS) cohort were studied. LEOSS is a European non-interventional multi-center cohort study established in March 2020 to investigate the epidemiology and clinical course of SARS-CoV-2 infection. Data from hospitalized patients and those who received ambulatory care, with a positive SARS-CoV-2 test, were included in the study. An additive effect of obesity, diabetes and hypertension on the risk of mortality was observed, which was particularly strong in young and middle-aged patients. Compared to young and middle-aged (18-55 years) patients without obesity, diabetes and hypertension (non-obese and metabolically healthy; n = 593), young and middle-aged adult patients with all three risk parameters (obese and metabolically unhealthy; n = 31) had a similar adjusted increased risk of mortality [OR 7.42 (95% CI 1.55-27.3)] as older (56-75 years) non-obese and metabolically healthy patients [n = 339; OR 8.21 (95% CI 4.10-18.3)]. Furthermore, increased CRP levels explained part of the elevated risk of COVID-19-related mortality with age, specifically in the absence of obesity and impaired metabolic health. In conclusion, the modifiable risk factors obesity, diabetes and hypertension increase the risk of COVID-19-related mortality in young and middle-aged patients to the level of risk observed in advanced age.

COVID-19 and metabolic disease: mechanisms and clinical management.

Up to 50% of the people who have died from COVID-19 had metabolic and vascular disorders. Notably, there are many direct links between COVID-19 and the metabolic and endocrine systems. Thus, not only are patients with metabolic dysfunction (eg, obesity, hypertension, non-alcoholic fatty liver disease, and diabetes) at an increased risk of developing severe COVID-19 but also infection with SARS-CoV-2 might lead to new-onset diabetes or aggravation of pre-existing metabolic disorders. In this Review, we provide an update on the mechanisms of how metabolic and endocrine disorders might predispose patients to develop severe COVID-19. Additionally, we update the practical recommendations and management of patients with COVID-19 and post-pandemic. Furthermore, we summarise new treatment options for patients with both COVID-19 and diabetes, and highlight current challenges in clinical management.

Postprandial Thermogenesis Is Reduced in Obesity

Background and Aims: Postprandial thermogenesis is thought to be important for the control of metabolism. This process could be reflected by minute changes in body temperature after glucose load. In this study, we measured body temperature before and its change during a glucose challenge and investigated the relationships with anthropometric and glycemic traits. Methods: We prospectively studied 383 volunteers (251 females, 132 males) with a mean age of 46.6 (SD ± 16) years and a BMI of 27.9 kg/m2 (SD ± 5.9). All participants underwent a 75 g oral glucose tolerance test (OGTT) and repeated bilateral measurements of intra-auricular temperature at time points 0, 30 and 120 minutes during the OGTT using a tympanic thermometer (Covidien Genius 2). Results: Baseline temperature was 0.17°C lower in males compared to females (p = 0.001) and inversely associated with age (p < 0.0001). During the OGTT, there was a significant increase in body temperature (0.18 ± 0.34°C). This response was present in females and males. BMI was negatively associated with the increase of temperature during the OGTT (p = 0.0147). Participants with higher BMI displayed higher fasting temperatures, but less increase of temperature during the OGTT. Body temperature was not associated with glycemia, insulin sensitivity or insulin secretion, neither in females nor males. Conclusions: There is a robust increase in body temperature during a glucose load that can be captured by intra-auricular temperature measurements. We did not detect any associations of the body temperature with glucose metabolism, arguing against a major contribution of the variability of body temperature in the pathogenesis of diabetes. However, the rise in temperature in response to oral glucose is reduced in obesity and might therefore be involved in body weight regulation. Disclosure: A. Vosseler: None. L. Fritsche: None. J. Hummel: None. C. Dannecker: None. N. Stefan: None. A.L. Birkenfeld: None. H. Haering: None. A. Fritsche: None. R. Wagner: Advisory Panel;Self;Novo Nordisk A/S. Speaker's Bureau;Self;Novo Nordisk A/S. Other Relationship;Self;Eli Lilly and Company. M. Heni: Research Support;Self;Boehringer Ingelheim Pharmaceuticals, Inc., Sanofi. Speaker's Bureau;Self;Novo Nordisk A/S. Funding: German Federal Ministry of Education and Research (01GI0925) [ABSTRACT FROM AUTHOR] Copyright of Diabetes is the property of American Diabetes Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hemostatic alterations linked to body fat distribution, fatty liver, and insulin resistance.

OBJECTIVE: Obesity, in particular visceral obesity, and insulin resistance emerged as major risk factors for severe coronavirus disease 2019 (COVID-19), which is strongly associated with hemostatic alterations. Because obesity and insulin resistance predispose to thrombotic diseases, we investigated the relationship between hemostatic alterations and body fat distribution in participants at risk for type 2 diabetes. SUBJECTS: Body fat distribution (visceral and subcutaneous abdominal adipose tissue) and liver fat content of 150 participants - with impaired glucose tolerance and/or impaired fasting glucose - were determined using magnetic resonance imaging and spectroscopy. Participants underwent precise metabolic characterization and major hemostasis parameters were analyzed. RESULTS: Procoagulant factors (FII, FVII, FVIII, and FIX) and anticoagulant proteins (antithrombin, protein C, and protein S) were significantly associated with body fat distribution. In patients with fatty liver, fibrinogen (298 mg/dl vs. 264 mg/dl, p = 0.0182), FVII (99% vs. 90%, p = 0.0049), FVIII (114% vs. 90%, p = 0.0098), protein C (124% vs. 111%, p = 0.0006), and protein S (109% vs. 89%, p < 0.0001) were higher than in controls. In contrast, antithrombin (97% vs. 102%, p = 0.0025) was higher in control patients. In multivariate analyses controlling for insulin sensitivity, body fat compartments, and genotype variants (PNPLA3I148MM/MI/TM6SF2E167kK/kE), only protein C and protein S remained significantly increased in fatty liver. CONCLUSIONS: Body fat distribution is significantly associated with alterations of procoagulant and anticoagulant parameters. Liver fat plays a key role in the regulation of protein C and protein S, suggesting a potential counteracting mechanism to the prothrombotic state in subjects with prediabetes and fatty liver.

Global pandemics interconnected - obesity, impaired metabolic health and COVID-19.

Obesity and impaired metabolic health are established risk factors for the non-communicable diseases (NCDs) type 2 diabetes mellitus, cardiovascular disease, neurodegenerative diseases, cancer and nonalcoholic fatty liver disease, otherwise known as metabolic associated fatty liver disease (MAFLD). With the worldwide spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), obesity and impaired metabolic health also emerged as important determinants of severe coronavirus disease 2019 (COVID-19). Furthermore, novel findings indicate that specifically visceral obesity and characteristics of impaired metabolic health such as hyperglycaemia, hypertension and subclinical inflammation are associated with a high risk of severe COVID-19. In this Review, we highlight how obesity and impaired metabolic health increase complications and mortality in COVID-19. We also summarize the consequences of SARS-CoV-2 infection for organ function and risk of NCDs. In addition, we discuss data indicating that the COVID-19 pandemic could have serious consequences for the obesity epidemic. As obesity and impaired metabolic health are both accelerators and consequences of severe COVID-19, and might adversely influence the efficacy of COVID-19 vaccines, we propose strategies for the prevention and treatment of obesity and impaired metabolic health on a clinical and population level, particularly while the COVID-19 pandemic is present.

Practical recommendations for the management of diabetes in patients with COVID-19.

Diabetes is one of the most important comorbidities linked to the severity of all three known human pathogenic coronavirus infections, including severe acute respiratory syndrome coronavirus 2. Patients with diabetes have an increased risk of severe complications including Adult Respiratory Distress Syndrome and multi-organ failure. Depending on the global region, 20-50% of patients in the coronavirus disease 2019 (COVID-19) pandemic had diabetes. Given the importance of the link between COVID-19 and diabetes, we have formed an international panel of experts in the field of diabetes and endocrinology to provide some guidance and practical recommendations for the management of diabetes during the pandemic. We aim to briefly provide insight into potential mechanistic links between the novel coronavirus infection and diabetes, present practical management recommendations, and elaborate on the differential needs of several patient groups.