The Critical Care Obesity Paradox and Implications for Nutrition Support

The association between body mass index and physical function in adult burn survivors: A Burn Model System National Database study

INTRODUCTION

An area of rehabilitation research in burns is the impact of co-morbidities on disease trajectory. Obesity is a comorbidity of increasing public health concern, but its role remains controversial regarding burn injury and physical recovery. Our aim was to evaluate the association between body mass index (BMI) categories as a measure of obesity at discharge and self-reported physical function (PF) during recovery of adult burn survivors.

METHODS

This is a retrospective study on data collected by four major US burn centers, which contribute to the Burn Model System National Database. The data included BMI obtained at hospital discharge and self-reported PF-mobility, using the PROMIS measures assessed at 6, 12, and 24 months after burn. Subjects were classified into weight status categories based on BMI: underweight (BMI <18.5), normal weight (18.5 ≤ BMI <25), overweight (25 ≤ BMI <30), obesity class 1 (30 ≤ BMI <35), obesity class 2 (35 ≤ BMI <40), and obesity class 3 (BMI ≥40). Mixed-effects linear regression models were used to assess the association between BMI categories and PF scores over time, adjusted for patient and injury characteristics.

RESULTS

A total of 496 adult burn patients aged 47 ± 16 years were included, with mean total body surface area (TBSA) burned of 18 ± 19 % and mean BMI at discharge of 28 ± 7 kg/m2. PROMIS PF scores significantly improved over time in the recovery phase after burn (time effect, p < 0.001). Compared to overweight burn patients, normal-underweights exhibited lower PF score by an average of 4.06 units (p = 0.001) but scores increased linearly by an estimated 0.17 units per month (p = 0.01) over the 24 months after discharge. Similarly, compared to overweight burn patients, class 1 obese reported lower PF score by a mean 2.67 units (p = 0.07) but PF increased linearly by 0.15 units per month (p = 0.07) over the 24 months after discharge. These findings were independent of the effects of age at discharge, sex, TBSA burned, and hand and leg burn.

CONCLUSION

Being overweight was associated with improved and faster recovery of PF scores compared to normal, underweight, and obese burn patients during long-term recovery. Hence, our data suggests that long-term recovery and restoration of PF in adult burn survivors is not compromised by a small excess in body weight.

Effect of Ketogenic Diet on Obesity and Other Metabolic Disorders: Narrative Review

Obesity is defined as an abnormal or excessive accumulation of fat that increases the burden of different chronic diseases in the population. It has reached epidemic proportions and is a major risk factor for a variety of diseases, including hypertension, cardiovascular disease, type 2 diabetes, dyslipidaemia, atherosclerosis, and some malignancies. Weight gain is a result of excessive energy intake compared to energy expenditure (energy loss from metabolism and physical exercise). A ketogenic diet has a more useful effect on obesity than other diets. A ketogenic diet is a low-carbohydrate, high-fat, moderate-protein diet that induces the production of ketone bodies by mimicking the breakdown of a fasting state. The mechanism behind the ketogenic diet is still unknown, although it obviously helps people with obesity lose weight. Several pathways for the ketogenic diet effect on weight loss have been hypothesized by researchers, including reduced appetite due to effects on appetite control hormones and a possible direct appetite suppressant action of ketone bodies; reduced lipogenesis and increased lipolysis; greater metabolic efficiency; and increased metabolic costs.

Lower quality of life in obese ICU survivors: a multicenter cohort study

PURPOSE

To compare health-related quality of life (HRQoL) and functional status between obese, underweight, normal-weight, and overweight patients after three months post-intensive care unit (ICU) discharge.

METHODS

Multicenter cohort study (10 Brazilian ICUs). 1600 ICU survivors (≥ 72 h in the ICU) were included.The main outcomes were HRQoL and functional status assessed three months after the ICU discharge. The secondary outcomes were mortality, hospital readmission, and ICU readmission during the same period.

RESULTS

Obese patients (median 50.1; IQR 39.6-59.6) had lower HRQoL in the mental component than normal-weight patients (median 53; IQR 45.6-60.1) (p = 0.033). No differences were found between BMI categories regarding the physical component of HRQoL and the Barthel Index (p = 0.355 and 0.295, respectively). Regarding readmissions, 65.1 and 25.1% of patients were readmitted to the hospital and ICU, but there was no difference between the groups (p = 0.870 and 0.220, respectively). Obese patients died less frequently (11.8%) than underweight (30.9%) and normal-weight (19.3%) patients (p < 0.001).

CONCLUSION

After three months of post-ICU discharge, obese patients had lower HRQoL in the mental component than normal-weight patients. However, obese patients died less than underweight and normal-weight patients.

Obesity Does Not Increase Risk for Mortality in Severe Sepsis Trauma Patients

INTRODUCTION

The prevalence of obesity in the United States is up to 40% in adults. Obese patients with severe sepsis have a lower mortality rate compared with normal body mass index (BMI) patients. We hypothesized that trauma patients with severe sepsis and obese BMI will have a decreased mortality risk in comparison with normal BMI patients.

METHODS

The Trauma Quality Improvement Program (2017) was queried for adult trauma patients with documented BMI and severe sepsis. Patients were grouped based on BMI: non-obese trauma patients (nOTP) BMI <30 kg/m2 and obese trauma patients (OTP) ≥30 kg/m2. A multivariable logistic regression model was used for analysis of mortality.

RESULTS

From 1246 trauma patients with severe sepsis, 566 (42.4%) were nOTP and 680 (57.6%) were OTP. OTP had increased length of stay (LOS) (19 vs 21 days, P < .001), intensive care unit (ICU) LOS (13 vs 18 days, P < .001) and ventilator days (10 vs 11 days, P < .001). After adjusting for covariates, when compared to normal BMI patients, patients who were overweight (OR 1.11 CI .875-1.41 P = .390), obese (OR .797 CI .59-1.06 P = .126), severely obese (OR .926 CI .63-1.36 P = .696) and morbidly obese (OR 1.448 CI 1.01-2.07 P = .04) all had a similar associated risk for mortality compared to patients with normal BMI.

CONCLUSION

In adult trauma patients with severe sepsis, this national analysis demonstrated OTP had increased LOS, ICU LOS, and ventilator days compared to nOTP. However, patients with increasing degrees of obesity had similar associated risk of mortality compared to trauma patients with severe sepsis and a normal BMI.

Anti-obesity potential of heat-killed Lactiplantibacillus plantarum K8 in 3T3-L1 cells and high-fat diet mice

Probiotics exert anti-obesity effects in high-fat diet (HFD) obese mice, but there are few studies on anti-obesity using heat-killed probiotics. Here, we investigated the effect of heat-killed Lactiplantibacillus plantarum K8 (K8HK) on the anti-differentiation of 3T3-L1 preadipocytes and on anti-obesity in HFD mice. K8HK decreased triglyceride (TG) accumulation in 3T3-L1 cells. Specifically, 1 × 10⁹ CFU/mL K8HK showed the greatest anti-obesity effect, while the same concentration of live L. plantarum K8 (K8 Live) showed cytotoxicity. K8HK increased suppressor of cytokine signaling (SOCS)-1, which might affect the JAK2-STAT3 signaling pathway activated during differentiation. As a result, the levels of transcription factors of adipogenesis such as Peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) decreased in K8HK-treated cells. We also observed a decrease in the lipogenic enzymes and fatty acid binding protein 4 (FABP4). In the mouse study, oral ingestion of K8 Live and K8HK showed weight reduction and decrease in blood TG content at 12 weeks of feeding. In addition, TG synthesis was suppressed in liver and adipose tissues, and genes related to fat metabolism were suppressed. This study suggests that K8HK could be a good material to prevent obesity by inhibiting adipogenesis genes related to fat metabolism.

Anti-obesity effect of Angelica keiskei Jiaosu prepared by yeast fermentation on high-fat diet-fed mice

In this study, an Angelica keiskei (A. keiskei) Jiaosu (FAK) was prepared by yeast fermentation to investigate its anti-obesity effect on high-fat diet (HFD)-fed mice. 70 SPF grade male C57BL/6J mice were randomly divided into 7 groups (n = 10): blank control group (N), high-fat model group (M), positive control group (Orl), unfermented control group (NF), high-dose intervention group (FH), medium-dose intervention group (FM), and low-dose intervention group (FL). The results showed that FAK intervention significantly reduced the body weight, Lee's index and liver index of HFD-fed mice (P < 0.05). Compared with M group, the serum levels of triglyceride (TG), total cholesterol (TC), leptin and glucose (GLU) in FH group were remarkably decreased and that of interleukin-27 (IL-27) were increased (P < 0.05). The levels of TG, and TC in the liver of mice were also markedly decreased in the FH group (P < 0.05). HE staining results showed that the liver cells in the three intervention groups had less degeneration and fatty vacuoles in the cytoplasm, and the liver cords were orderly arranged compared with that of M group. Furthermore, FAK significantly inhibited epididymal adipose tissue cell expansion induced by HFD. FAK up-regulated the protein expression levels of p-AMPK and PPARα to promote lipolysis and down-regulated the expression of PPARγ to reduce lipid synthesis (P < 0.05). Additionally, the results of gut microbiota showed that after the intervention, a decrease trend of F/B value and Deferribacterota was noticed in the FH group compared with M group. At the genus level, FAK intervention significantly increased that of Ileiobacterium compared to the M group (p < 0.05). A rising trend of norank_f_Muribaculaceae, Lactobacillus, and Bifidobacterium were also observed in the HF group. Conclusively, these findings demonstrated that FAK intervention can effectively improve obesity in mice caused by HFD and the potential mechanisms was related to the regulation of serum levels of leptin and IL-27, lipogenesis and lipolysis in adipose tissue and gut microbiota composition.

Increasing Trends in Obesity-Related Cardiovascular Risk Factors in Romanian Children and Adolescents-Retrospective Study

Childhood obesity has become a global public health issue and its assessment is essential, as an obese child is a future overweight or obese adult. Obesity is no longer a matter of exercising more and eating less, with several factors coming into play and dictating the pattern of fat accumulation and the ease/difficulty of reducing it. In the current paper, we aimed to analyze the cardiovascular impact of obesity in a large number of patients alongside the paraclinical changes that occur due to weight gain, and to perform an analysis on the increase in prevalence throughout our research. The main cardiovascular conditions identified were hypertension (15.36%), septal or concentric hypertrophic cardiomyopathy (11.15%), atherosclerosis risk (13.04%), and hypercholesterolemia (20.94%). We have used echocardiography to measure the thickness of epicardial adipose tissue (useful for assessing the patient's cardiovascular risk), and we observed that it was greater in children with moderate and severe obesity alongside diastolic dysfunction of the left ventricle in the whole group, without any connection with hypertension or coronary impairment. Obese children will be affected by increased cardiovascular mortality and morbidity in adulthood and they may experience early cardiovascular dysfunction. We want to strongly underline the importance and necessity of programs for the early detection and prevention of obesity and its complications, especially since interesting phenomena such as the "obesity paradox" exist and prove that obesity is far less understood than it is at a first glance.

Interpretable machine learning for 28-day all-cause in-hospital mortality prediction in critically ill patients with heart failure combined with hypertension: A retrospective cohort study based on medical information mart for intensive care database-IV and eICU databases

Background

Heart failure (HF) combined with hypertension is an extremely important cause of in-hospital mortality, especially for the intensive care unit (ICU) patients. However, under intense working pressure, the medical staff are easily overwhelmed by the large number of clinical signals generated in the ICU, which may lead to treatment delay, sub-optimal care, or even wrong clinical decisions. Individual risk stratification is an essential strategy for managing ICU patients with HF combined with hypertension. Artificial intelligence, especially machine learning (ML), can develop superior models to predict the prognosis of these patients. This study aimed to develop a machine learning method to predict the 28-day mortality for ICU patients with HF combined with hypertension.

Methods

We enrolled all critically ill patients with HF combined with hypertension in the Medical Information Mart for IntensiveCare Database-IV (MIMIC-IV, v.1.4) and the eICU Collaborative Research Database (eICU-CRD) from 2008 to 2019. Subsequently, MIMIC-IV was divided into training cohort and testing cohort in an 8:2 ratio, and eICU-CRD was designated as the external validation cohort. The least absolute shrinkage and selection operator (LASSO) Cox regression with internal tenfold cross-validation was used for data dimension reduction and identifying the most valuable predictive features for 28-day mortality. Based on its accuracy and area under the curve (AUC), the best model in the validation cohort was selected. In addition, we utilized the Shapley Additive Explanations (SHAP) method to highlight the importance of model features, analyze the impact of individual features on model output, and visualize an individual’s Shapley values.

Results

A total of 3,458 and 6582 patients with HF combined with hypertension in MIMIC-IV and eICU-CRD were included. The patients, including 1,756 males, had a median (Q1, Q3) age of 75 (65, 84) years. After selection, 22 out of a total of 58 clinical parameters were extracted to develop the machine-learning models. Among four constructed models, the Neural Networks (NN) model performed the best predictive performance with an AUC of 0.764 and 0.674 in the test cohort and external validation cohort, respectively. In addition, a simplified model including seven variables was built based on NN, which also had good predictive performance (AUC: 0.741). Feature importance analysis showed that age, mechanical ventilation (MECHVENT), chloride, bun, anion gap, paraplegia, rdw (RDW), hyperlipidemia, peripheral capillary oxygen saturation (SpO₂), respiratory rate, cerebrovascular disease, heart rate, white blood cell (WBC), international normalized ratio (INR), mean corpuscular hemoglobin concentration (MCHC), glucose, AIDS, mean corpuscular volume (MCV), N-terminal pro-brain natriuretic peptide (Npro. BNP), calcium, renal replacement therapy (RRT), and partial thromboplastin time (PTT) were the top 22 features of the NN model with the greatest impact. Finally, after hyperparameter optimization, SHAP plots were employed to make the NN-based model interpretable with an analytical description of how the constructed model visualizes the prediction of death.

Conclusion

We developed a predictive model to predict the 28-day mortality for ICU patients with HF combined with hypertension, which proved superior to the traditional logistic regression analysis. The SHAP method enables machine learning models to be more interpretable, thereby helping clinicians to better understand the reasoning behind the outcome and assess in-hospital outcomes for critically ill patients.

Obesity Worsens Local and Systemic Complications of Necrotizing Pancreatitis and Prolongs Disease Course

BACKGROUND

Obesity is epidemic in the USA. Limited data exist examining obesity's influence on necrotizing pancreatitis (NP) disease course.

METHODS

Retrospective review of prospectively maintained database of 571 adult necrotizing pancreatitis patients treated between 2007 and 2018. Patients were grouped according to body mass index (BMI) at disease onset. Patient characteristics, necrotizing pancreatitis course, and outcomes were compared between non-obese (BMI < 30) and obese (BMI > 30) patients.

RESULTS

Among 536 patients with BMI data available, 304 (57%) were obese (BMI > 30), and 232 (43%) were non-obese (BMI < 30). NP etiology in the obese group was more commonly biliary (55% versus 46%, p = 0.04) or secondary to hypertriglyceridemia (10% versus 2%, p < 0.001) and less commonly alcohol (17% versus 26%, p = 0.01). Obese patients had a higher incidence of baseline comorbid disease. The CT severity index was similar between groups though obese patients had a higher rate of > 50% pancreatic gland necrosis (27% versus 19%, p = 0.02). The rates of infected necrosis and organ failure were higher among obese patients. Percutaneous drainage was more common in obese patients. Time to first necrosis intervention was earlier with increasing BMI. NP disease duration was longer in obese patients. The overall mortality rate of non-obese and obese patients did not differ. However, mortality rate increased with increasing BMI.

CONCLUSION

Necrotizing pancreatitis in obese patients is characterized by a prolonged disease course, a higher risk of organ failure, infected necrosis, and the need for early necrosis-related intervention. Mortality increases with increasing BMI.

Nutritional risk, not obesity, is associated with mortality in critically ill COVID-19 patients

Background

Despite the identification of obesity as a risk factor for higher rates of hospital and Intensive Care Unit (ICU) admissions and complications due to COVID-19, the association between obesity and mortality in critically ill COVID-19 patients remains controversial, and the nutritional risk is little considered. Hence, our study sought to evaluate the association between obesity, nutritional risk, and mortality in critically ill patients diagnosed with COVID-19.

Methods

Retrospective study were condutcted including adult critically ill COVID-19 patients admitted to an ICU between April 2020 and March 2021. Clinical and laboratory data were collected from electronic medical records. Obesity was classified by body mass index ≥ 30 kg/m^2. A mNUTRIC score of ≥ 5 indicated high nutritional risk. Multiple Cox Regression was used to estimate the association between mNUTRIC, obesity, and mortality.

Results

From 71 patients aged 59 (± 15) years, 71.8 % were male. The frequencies of obesity (58.7 %) and death (49.3 %) were high, but obesity was not associated with mortality. Based on mNUTRIC, 85.9 % of patients were at high nutritional risk, presenting a higher frequency of mortality than patients at low nutritional risk (50.8 % vs 40.0 %; p = 0.014). Multiple Cox Regression showed that for each unit increase in mNUTRIC score the probability of death almost doubled, regardless of the presence of obesity (HR = 1.74; p < 0.001).

Conclusions

A higher nutritional risk was positively associated with mortality in critically ill COVID-19 patients, regardless of obesity, showing the importance of early identification of nutritional risk for appropriate nutritional interventions in this population.

Systems biology approach identifies key genes and related pathways in childhood obesity

BACKGROUND

Childhood obesity is triggered by a complex interplay of environmental, genetic, and epigenetic factors; however, the molecular mechanisms behind this disease are not completely elucidated. Thus, the aim of this study was to investigate molecular mechanisms involved in childhood obesity by implementing a systems biology approach.

METHODS

Experimentally validated and computationally predicted genes related to childhood obesity were downloaded from DisGeNET database. A protein-protein interaction (PPI) network was constructed using the STRING database and analyzed at Cytoscape web-tool. Hub-bottleneck genes and functional clusters were identified through CytoHubba and MCODE plugins, respectively. Functional enrichment analyses were performed based on Gene Ontology terms and KEGG Pathways.

RESULTS

The DisGeNET search retrieved 191 childhood obesity-related genes. The resulting PPI network contained 12 hub-bottleneck genes (INS, LEP, STAT3, POMC, ALB, TNF, BDNF, CAT, GCG, PPARG, VEGFA, and ADIPOQ) and 4 functional clusters, with cluster 1 showing the highest interaction score. Genes at this cluster were enriched at inflammation, carbohydrate, and lipid metabolism pathways. With exception of POMC, all hub-bottleneck genes were found in cluster 1, which contains highly connected genes that possibly play key roles in obesity-related pathways.

CONCLUSIONS

Our systems biology approach revealed a set of highly interconnected genes associated with childhood obesity, providing comprehensive information regarding genetic and molecular factors involved in the pathogenesis of this disease.

"Obesity paradox" has not an impact on minimally invasive anatomical lung resection

INTRODUCTION

The paradoxical benefit of obesity, the 'obesity paradox', has been analyzed in lung surgical populations with contradictory results. Our goal was assessing the relationship of body mass index (BMI) to acute outcomes after minimally invasive major pulmonary resections.

METHODS

Retrospective review of consecutive patients who underwent pulmonary anatomical resection through a minimally invasive approach for the period 2014-2019. Patients were grouped as underweight, normal, overweight and obese type I, II and III. Adjusted odds ratios regarding postoperative complications (overall, respiratory, cardiovascular and surgical morbidity) were produced with their exact 95% confidence intervals. All tests were considered statistically significant at p<0.05.

RESULTS

Among 722 patients included in the study, 37.7% had a normal BMI and 61.8% were overweight or obese patients. When compared with that of normal BMI patients, adjusted pulmonary complications were significantly higher in obese type I patients (2.6% vs 10.6%, OR: 4.53 [95%CI: 1.86-12.11]) and obese type II-III (2.6% vs 10%, OR: 6.09 [95%CI: 1.38-26.89]). No significant differences were found regarding overall, cardiovascular or surgical complications among groups.

CONCLUSIONS

Obesity has not favourable effects on early outcomes in patients undergoing minimally invasive anatomical lung resections, since the risk of respiratory complications in patients with BMI≥30kg/m² and BMI≥35kg/m² is 4.5 and 6 times higher than that of patients with normal BMI.

Obesity in the Critical Care Setting

The prevalence of obesity continues to rise and is caused by many factors. Obesity places patients at risk for high blood pressure, diabetes, heart disease, and cancer. Although obesity in the normal population is associated with increased morbidity and mortality, obesity in critically ill patients has lower mortality. This is referred to as the obesity paradox, and although not fully understood, involves several mechanisms that demonstrate a protective factor in critically ill obese patients. However, despite the benefit, the management of critically ill obese patients faces many challenges.

Pathophysiological Molecular Mechanisms of Obesity: A Link between MAFLD and NASH with Cardiovascular Diseases

Obesity is now a worldwide epidemic ensuing an increase in comorbidities' prevalence, such as insulin resistance, type 2 diabetes (T2D), metabolic dysfunction-associated fatty liver disease (MAFLD), nonalcoholic steatohepatitis (NASH), hypertension, cardiovascular disease (CVD), autoimmune diseases, and some cancers, CVD being one of the main causes of death in the world. Several studies provide evidence for an association between MAFLD and atherosclerosis and cardio-metabolic disorders, including CVDs such as coronary heart disease and stroke. Therefore, the combination of MAFLD/NASH is associated with vascular risk and CVD progression, but the underlying mechanisms linking MAFLD/NASH and CVD are still under investigation. Several underlying mechanisms may probably be involved, including hepatic/systemic insulin resistance, atherogenic dyslipidemia, hypertension, as well as pro-atherogenic, pro-coagulant, and pro-inflammatory mediators released from the steatotic/inflamed liver. MAFLD is strongly associated with insulin resistance, which is involved in its pathogenesis and progression to NASH. Insulin resistance is a major cardiovascular risk factor in subjects without diabetes. However, T2D has been considered the most common link between MAFLD/NASH and CVD. This review summarizes the evidence linking obesity with MAFLD, NASH, and CVD, considering the pathophysiological molecular mechanisms involved in these diseases. We also discuss the association of MAFLD and NASH with the development and progression of CVD, including structural and functional cardiac alterations, and pharmacological strategies to treat MAFLD/NASH and cardiovascular prevention.

Nutrition Therapy in Critically Ill Overweight Elderly Patient with Heart Failure, Myocardial Infarction, Pneumonia, and Chronic Kidney Disease

Overweight or obesity will increase the risk of morbidity and mortality from cardiovascular disease. In older people, the risk is higher, but also paradoxically associated with lower mortality rates. Overweight patients vary in body composition and when it coupled with limited reliable sources to make caloric requirements estimation will make nutrition therapy extremely challenging. This case study reveals the nutrition therapy support in critically ill overweight elderly patient with heart failure, myocardial infarction, pneumonia, and chronic kidney disease. An 80-year old moderate malnourished male patient (body mass index 24.6 kg/m²) with acute lung edema, cardiogenic shock, myocardial infarction, pneumonia, and chronic kidney disease was admitted in the cardiovascular intensive-care unit. The patient was treated with diuretics, vasopressor support, and antibiotics. Oral intake was reduced due to shortness of breath and loss of appetite. The physical examination revealed basal lung rales, wheezing, muscle wasting, edema. Blood tests showed hyperkalemia, leucocytosis, depletion of the immune system, hyperuricemia, hypoalbuminemia, and dyslipidemia. The patient was on stage 5 renal failure (GFR 6.2 mL/min) but refused hemodialysis treatment. Nutritional therapy was given gradually with calorie target 1900 kcal and protein 0.6-1.2 g/ideal body weight/d using normal foods, oral nutrition supplement, and amino acids parenteral nutrition. After 13 d of nutritional treatment, the patient was discharged from the hospital with no shortness of breath, adequate nutrition intake, increased renal function (GFR 22.4 mL/min), and improvement of the blood test results (immune status, uric acid, albumin, and lipid profile). Critically ill overweight elderly patients are hypercatabolic and have increased nutrient demands. Nutritional support in these patients is required to provide necessary nutrient substrates and to alter the course and outcome of the disease.

Prediction model of in-hospital mortality in intensive care unit patients with heart failure: machine learning-based, retrospective analysis of the MIMIC-III database

OBJECTIVE

The predictors of in-hospital mortality for intensive care units (ICUs)-admitted heart failure (HF) patients remain poorly characterised. We aimed to develop and validate a prediction model for all-cause in-hospital mortality among ICU-admitted HF patients.

DESIGN

A retrospective cohort study.

SETTING AND PARTICIPANTS

Data were extracted from the Medical Information Mart for Intensive Care (MIMIC-III) database. Data on 1177 heart failure patients were analysed.

METHODS

Patients meeting the inclusion criteria were identified from the MIMIC-III database and randomly divided into derivation (n=825, 70%) and a validation (n=352, 30%) group. Independent risk factors for in-hospital mortality were screened using the extreme gradient boosting (XGBoost) and the least absolute shrinkage and selection operator (LASSO) regression models in the derivation sample. Multivariate logistic regression analysis was used to build prediction models in derivation group, and then validated in validation cohort. Discrimination, calibration and clinical usefulness of the predicting model were assessed using the C-index, calibration plot and decision curve analysis. After pairwise comparison, the best performing model was chosen to build a nomogram according to the regression coefficients.

RESULTS

Among the 1177 admissions, in-hospital mortality was 13.52%. In both groups, the XGBoost, LASSO regression and Get With the Guidelines-Heart Failure (GWTG-HF) risk score models showed acceptable discrimination. The XGBoost and LASSO regression models also showed good calibration. In pairwise comparison, the prediction effectiveness was higher with the XGBoost and LASSO regression models than with the GWTG-HF risk score model (p<0.05). The XGBoost model was chosen as our final model for its more concise and wider net benefit threshold probability range and was presented as the nomogram.

CONCLUSIONS

Our nomogram enabled good prediction of in-hospital mortality in ICU-admitted HF patients, which may help clinical decision-making for such patients.

"Obesity paradox" has not an impact on minimally invasive anatomical lung resection

INTRODUCTION

The paradoxical benefit of obesity, the 'obesity paradox', has been analyzed in lung surgical populations with contradictory results. Our goal was assessing the relationship of body mass index (BMI) to acute outcomes after minimally invasive major pulmonary resections.

METHODS

Retrospective review of consecutive patients who underwent pulmonary anatomical resection through a minimally invasive approach for the period 2014-2019. Patients were grouped as underweight, normal, overweight and obese type I, II and III. Adjusted odds ratios regarding postoperative complications (overall, respiratory, cardiovascular and surgical morbidity) were produced with their exact 95% confidence intervals. All tests were considered statistically significant at p<0.05.

RESULTS

Among 722 patients included in the study, 37.7% had a normal BMI and 61.8% were overweight or obese patients. When compared with that of normal BMI patients, adjusted pulmonary complications were significantly higher in obese type I patients (2.6% vs 10.6%, OR: 4.53 [95%CI: 1.86-12.11]) and obese type II-III (2.6% vs 10%, OR: 6.09 [95%CI: 1.38-26.89]). No significant differences were found regarding overall, cardiovascular or surgical complications among groups.

CONCLUSIONS

Obesity has not favourable effects on early outcomes in patients undergoing minimally invasive anatomical lung resections, since the risk of respiratory complications in patients with BMI≥30kg/m2 and BMI≥35kg/m2 is 4.5 and 6 times higher than that of patients with normal BMI.

Nitrogen balance in mechanically ventilated obese patients

ABSTRACT Objective This study aimed to evaluate if the protein intake recommendations for obese critically ill requiring mechanical ventilation are sufficient to promote a positive or neutral nitrogen balance. Methods Cross-sectional study that included 25 obese, ≥18 years old, undergoing mechanical ventilation and who were target to receive high-protein enteral nutrition therapy (2.0-2.5g/kg ideal body weight). Clinical, nutritional and biochemical variables were analyzed. Nitrogen balance was performed when patient was receiving full enteral nutrition therapy and was classified: positive when intake was greater than excretion; negative when excretion was greater than intake; neutral when both were equal. Results The characteristics of patients evaluated were 64.1±9.4 years old, clinical treatment 88%, body mass index 36.5±5.1kg/m2, nitrogen balance 0.3g/day (-5.3 to 4.8g/day), protein intake 2.1g/day (2.0-2.3g/kg) ideal body weight. Of individuals analyzed, 52% showed positive or neutral nitrogen balance with median of 4.23g/day 2.41 to 6.40g/day) in comparison to negative group with median of -5.27g/day (-10.38 to -3.86g/day). Adults had higher ratio of negative nitrogen balance (57.1%) than elderly (44.4%), with protein intake of 2.0 versus 2.1g/day, respectively. No correlation was found between nitrogen balance and variables assessed. Conclusion High-protein enteral nutrition therapy contributed to positive or neutral nitrogen balance for approximately half of obese ventilated individuals. With similar protein intake, elderly showed a higher proportion of positive or neutral nitrogen balance. Nitrogen balance can be influenced by various factors, so further studies are required to identify different protein needs in obese critically.

The obesity paradox in critically ill patients: a causal learning approach to a casual finding

Background

While obesity confers an increased risk of death in the general population, numerous studies have reported an association between obesity and improved survival among critically ill patients. This contrary finding has been referred to as the obesity paradox. In this retrospective study, two causal inference approaches were used to address whether the survival of non-obese critically ill patients would have been improved if they had been obese.

Methods

The study cohort comprised 6557 adult critically ill patients hospitalized at the Intensive Care Unit of the Ghent University Hospital between 2015 and 2017. Obesity was defined as a body mass index of ≥ 30 kg/m². Two causal inference approaches were used to estimate the average effect of obesity in the non-obese (AON): a traditional approach that used regression adjustment for confounding and that assumed missingness completely at random and a robust approach that used machine learning within the targeted maximum likelihood estimation framework along with multiple imputation of missing values under the assumption of missingness at random. 1754 (26.8%) patients were discarded in the traditional approach because of at least one missing value for obesity status or confounders.

Results

Obesity was present in 18.9% of patients. The in-hospital mortality was 14.6% in non-obese patients and 13.5% in obese patients. The raw marginal risk difference for in-hospital mortality between obese and non-obese patients was − 1.06% (95% confidence interval (CI) − 3.23 to 1.11%, P = 0.337). The traditional approach resulted in an AON of − 2.48% (95% CI − 4.80 to − 0.15%, P = 0.037), whereas the robust approach yielded an AON of − 0.59% (95% CI − 2.77 to 1.60%, P = 0.599).

Conclusions

A causal inference approach that is robust to residual confounding bias due to model misspecification and selection bias due to missing (at random) data mitigates the obesity paradox observed in critically ill patients, whereas a traditional approach results in even more paradoxical findings. The robust approach does not provide evidence that the survival of non-obese critically ill patients would have been improved if they had been obese.

Association of obesity with morbidity and mortality in critically ill children: a systematic review and meta-analysis of observational studies

Recent studies have suggested that obesity might be protective in specific conditions such as critical illness; however, there are controversial data in critically ill children with obesity. The aim of this study was to investigate the association of obesity with mortality and other outcomes in these patients. We conducted a systematic review of observational studies investigating obesity in critically ill children, published by August 2017 in PubMed and Scopus. After screening documents, 15 articles with 142119 patients were included in the systematic review and meta-analysis. The results were reported with odds ratio (OR) or standard mean difference (SMD). The primary outcome was mortality and the secondary outcomes were length of ICU stay (ICU LOS), length of hospital stay (hospital LOS), and duration of mechanical ventilation (MV). The analysis showed that critically ill children without obesity had lower risk of mortality compared to patients with obesity (OR 0.79, 95% CI 0.64 to 0.97, P = 0.025, I² = 35.2%). Hospital LOS was also significantly lower in children without obesity (pooled SMD -0.12, 95% CI -0.21 to -0.04, P = 0.004, I² = 8.1%). There were no differences in ICU LOS (95% CI -0.19 to 0.01, P = 0.083) and duration of MV (95% CI -0.22 to 0.03, P = 0.136) between critically ill children with and without obesity. In conclusion, the current systematic review and meta-analysis revealed that critically ill children with obesity have higher risk of mortality and length of hospital stay compared to the group without obesity. Further prospective studies are essential to elucidate the role of obesity and underlying mechanisms in predicting outcomes of critically ill children.

Effects of Redox Disturbances on Intestinal Contractile Reactivity in Rats Fed with a Hypercaloric Diet

Few studies have associated the effects of changes in caloric intake and redox disturbances in the gastrointestinal tract. Therefore, the present study aimed at evaluating the hypercaloric diet consumption influence on the contractile reactivity of intestinal smooth muscle, morphology, and oxidative stress of rat ileum. Wistar rats were randomly divided into groups that received a standard diet and fed with a hypercaloric diet for 8 weeks. Animals were euthanized, and the ileum was isolated to isotonic contraction monitoring. Morphology was evaluated by histological staining and oxidative stress by quantification of malondialdehyde levels and total antioxidant activity. Cumulative concentration-response curves to KCl and carbachol were attenuated in rats fed with a hypercaloric diet compared to those that received a standard diet. In addition, an increase in caloric intake promotes a rise in the thickness of the longitudinal smooth muscle layer of rat ileum and tissue malondialdehyde levels, characterizing lipid peroxidation, as well as a decrease in the antioxidant activity. Thus, it was concluded that the consumption of a hypercaloric diet impairs rat intestinal contractility due to mechanisms involving modifications in the intestinal smooth muscle architecture triggered by redox disturbances.

Effect of hypocaloric normoprotein or trophic feeding versus target full enteral feeding on patient outcomes in critically ill adults: a systematic review

Uncertainty surrounds the optimal approach to feeding the critically ill, with increasing interest in the concept of intentional underfeeding to reduce metabolic stress while maintaining gut integrity. Conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this systematic review evaluates clinical outcomes reported in studies comparing hypocaloric normonitrogenous or trophic feeding (collectively 'intentional underfeeding') targeted full energy feeding administered via enteral nutrition to adult critically ill patients. Electronic databases including PubMed, CINAHL, EMBASE and CENTRAL were searched up to September 2017 for trials evaluating intentional underfeeding versus targeted energy feeding interventions on clinical outcomes (mortality, length of stay, duration of ventilation, infective complications, feeding intolerance and glycaemic control) among critically ill adult patients. Bias of included studies was assessed using the Cochrane risk of bias tool. Of the 595 articles identified, seven studies (six randomised controlled trials, one non-randomised trial) met the inclusion criteria, representing 2,684 patients (hypocaloric normonitrogenous n=668; trophic n=681; full energy feeding n=1335). Across the studies, there was considerable heterogeneity in study methodology, population, feeding strategy and outcomes and their timepoints. We observed no evidence that intentional underfeeding, when compared to targeting full energy feeding, reduced mortality or duration of ventilation or length of stay. However, limited trial evidence is available on the impact of intentional underfeeding on post-discharge functional and quality of life outcomes.

Diet-induced obesity alters memory consolidation in female rats

Obesity is a multifactorial disease characterized by the abnormal or excessive fat accumulation, which is caused by an energy imbalance between consumed and expended calories. Obesity leads to an inflammatory response that may result in peripheral and central metabolic changes, including insulin and leptin resistance. Insulin and leptin resistance have been associated with metabolic and cognitive dysfunctions. Obesity and some neurodegenerative diseases that lead to dementia affect mainly women. However, the effects of diet-induced obesity on memory consolidation in female rats are poorly understood. Therefore, the aim of this study was to evaluate the effect of a hypercaloric diet on the object recognition memory of female rats and on possible related metabolic changes. The animals submitted to the hypercaloric diet presented a higher food intake in grams and in calories, resulting in increased weight gain and liposomatic index in comparison with the animals exposed to the control diet. These animals presented a memory deficit in the object recognition test and increased serum levels of glucose and leptin. However, no significant differences were found in the serum levels of insulin, TNF-α and IL-1β, in the index of insulin resistance (HOMA), in the hippocampal levels of insulin, TNF-α and IL-1β, as well as on Akt expression or activation in the hippocampus. Our findings indicate that adult female rats submitted to a hypercaloric diet present memory consolidation impairment, which could be associated with diet-induced weight gain and leptin resistance, even without the development of insulin resistance.

Micronutrient Deficiencies After Bariatric Surgery: An Emphasis on Vitamins and Trace Minerals [Formula: see text]

Obesity has become a worldwide epidemic with a disproportionate increase in grade III obesity. Bariatric surgery offers an attractive option for sustained weight loss compared with traditional methods such as exercise and diet. Micronutrient deficiencies are common and clinically significant after bariatric surgery. These deficiencies are related to a combination of patient and surgical variables. A thorough understanding of specific micronutrient deficiencies is necessary for early recognition and optimal management. The purpose of this review is to describe indications, outcomes, and types of bariatric procedures, risk factors, and mechanisms for micronutrient deficiencies, as well as outline specific vitamin and trace element deficiencies after bariatric surgery.

Morinda citrifolia Linn. (Noni) and Its Potential in Obesity-Related Metabolic Dysfunction

Cultural and economic shifts in the early 19th century led to the rapid development of companies that made good profits from technologically-produced commodities. In this way, some habits changed in society, such as the overconsumption of processed and micronutrient-poor foods and devices that gave rise to a sedentary lifestyle. These factors influenced host-microbiome interactions which, in turn, mediated the etiopathogenesis of “new-era” disorders and diseases, which are closely related, such as obesity, type 2 diabetes mellitus, non-alcoholic fatty liver disease, hypertension, and inflammatory bowel disease, which are characterized by chronic dysregulation of metabolic and immune processes. These pathological conditions require novel and effective therapeutic approaches. Morindacitrifolia (noni) is well known as a traditional healing plant due to its medicinal properties. Thus, many studies have been conducted to understand its bioactive compounds and their mechanisms of action. However, in obesity and obesity-related metabolic (dysfunction) syndrome, other studies are necessary to better elucidate noni’s mechanisms of action, mainly due to the complexity of the pathophysiology of obesity and its metabolic dysfunction. In this review, we summarize not only the clinical effects, but also important cell signaling pathways in in vivo and in vitro assays of potent bioactive compounds present in the noni plant which have been reported in studies of obesity and obesity-associated metabolic dysfunction.

Protein Requirements for Critically Ill Patients With Renal and Liver Failure

Diseases leading to critical illness induce proteolysis resulting in muscle wasting and negative nitrogen balance. Muscle wasting has been associated with poor intensive care unit (ICU)-related outcomes, including an increased risk for mortality. Acute kidney injury (AKI) represents a common organ dysfunction associated with ICU-related disorders, such as sepsis, trauma, and respiratory failure. AKI and renal replacement therapy lead to amino acid loss. Decompensated liver cirrhosis (DLC) and acute liver failure (ALF) represent more severe forms of liver dysfunction leading to ICU admission. DLC and ALF are associated with proteolysis and amino acid loss. AKI, DLC, and ALF uniquely contribute to negative nitrogen balance. The purpose of this review is to outline proteolysis associated with critical illness; define specific protein abnormalities in AKI, DLC, and ALF; define protein requirements in AKI, DLC, and ALF; and discuss barriers associated with optimal protein supplementation in these disorders.