Obesity Paradox in Patients with Acute Coronary Syndrome: Is Malnutrition the Answer?

BACKGROUND: Obesity paradox has been reported in patients with cardiovascular disease, showing an inverse association between obesity as defined by BMI (in kg/m2) and prognosis. Nutritional status is associated with systemic inflammatory response and affects cardiovascular disease outcomes. OBJECTIVES: This study sought to examine the influence of obesity and malnutrition on the prognosis of patients with acute coronary syndrome (ACS). METHODS: This study included consecutive patients diagnosed with ACS and underwent coronary angiogram between January 2009 and February 2023. At baseline, patients were categorized according to their BMI as follows: underweight (<18), normal weight (18-24.9), overweight (25.0-29.9), and obese (>30.0). We assessed the nutritional status by Prognostic Nutritional Index (PNI). Malnutrition was defined as a PNI value of <38. RESULTS: Of the 21,651 patients with ACS, 582 (2.7%) deaths from any cause were observed over 28.7 months. Compared with the patient's state of normal weight, overweight, and obesity were associated with decreased risk of all-cause mortality. Malnutrition was independently associated with poor survival (hazards ratio: 2.64; 95% CI: 2.24, 3.12; P < 0.001). In malnourished patients, overweight and obesity showed a 39% and 72% reduction in the incidence of all-cause mortality, respectively. However, in nourished patients, no significant reduction in the incidence of all-cause mortality was observed (all P > 0.05). CONCLUSIONS: Obesity paradox appears to occur in patients with ACS. Malnutrition may be a significant independent risk factor for prognosis in patients with ACS. The obesity paradox is influenced by the status of malnutrition.

Association of systemic inflammation with the obesity paradox in cancer: results from multi-cohort studies.

AIMS: This study aimed to explore whether the obesity paradox exists in overall and specific cancers and to investigate the role of systemic inflammation in the obesity paradox. METHODS: The Cox proportional hazard model was used to explore the relationship between body mass index (BMI) and all-cause mortality. The mediated effect was used to investigate the proportion of systemic inflammation mediating the relationship between BMI and cancer survival risk. RESULTS: The survival probability showed a step-like increase with an increase in BMI regardless of pathological stage. Approximately 10.8%-24.0% of the overall association between BMI and all-cause mortality in cancer was mediated by inflammation. In the internal validation, we found evidence of the obesity paradox in all body composition obtained using BIA, with inflammation remaining an important mediating factor. Furthermore, we also validated the existence of the obesity paradox of cancer in NHANES. Systemic inflammation remains an important factor in mediating the association between BMI and prognosis in cancer patients. CONCLUSIONS: The obesity paradox is prevalent in most cancers, except for hepatic biliary cancer and breast cancer. Inflammation may be one of the true features of the obesity paradox in cancer.

Debunking the "Obesity Paradox": Obesity Is Associated With Adverse Outcomes in Emergency General Surgery.

INTRODUCTION: Obesity is increasingly prevalent both nationwide and in the emergency general surgery (EGS) population. While previous studies have shown that obesity may be protective against mortality following EGS procedures, the association between body mass index (BMI) and postoperative outcomes, as well as intraoperative decision-making, remains understudied. METHODS: The National Surgical Quality Improvement Program 2015-2019 database was used to identify all adult patients undergoing an open abdominal or abdominal wall procedure for EGS conditions. Our outcomes included 30-d postoperative mortality, composite 30-d morbidity, delayed fascial closure, reoperation, operative time, and hospital length of stay (LOS). Multivariable logistic regression models were used to explore the association between BMI and each outcome of interest while adjusting for patient demographics, comorbidities, laboratory tests, preoperative and intraoperative variables. RESULTS: We identified 78,578 patients, of which 3121 (4%) were categorized as underweight, 23,661 (30.1%) as normal weight, 22,072 (28.1%) as overweight, 14,287 (18.2%) with class I obesity, 7370 (9.4%) with class II obesity, and 8067 (10.3%) with class III obesity. Class III obesity was identified as a risk factor for 30-d postoperative morbidity (adjusted odds ratio 1.14, 95% CI, 1.03-1.26, P < 0.01). An increase in obesity class was also associated with a stepwise increase in the risk of undergoing delayed fascial closure, experiencing a prolonged operative time, and having an extended LOS. CONCLUSIONS: Obesity class was associated with an increase in delayed fascial closure, longer operative time, higher reoperation rates, and extended hospital LOS. Further studies are needed to explore how a patient's BMI impacts intraoperative factors, influences surgical decision-making, and contributes to hospital costs.

Positive impact of obesity on the prognosis of liver cirrhosis.

BACKGROUND AND AIM: The study aims to determine the prognostic impact of obesity, sarcopenic obesity, and dynapenic obesity in patients with chronic liver disease. METHODS: This retrospective observational study enrolled patients with chronic hepatitis (n = 746) and liver cirrhosis (n = 434) without hepatocellular carcinoma at entry. The patients were evaluated for sarcopenia and obesity between April 2016 and April 2022. Obesity was defined as a body mass index of ≥ 25 kg/m2. Sarcopenic obesity was defined as low skeletal muscle mass (pre-sarcopenia) with obesity and dynapenic obesity was defined as low muscle strength (dynapenia) with obesity. The effects of obesity on survival were evaluated retrospectively. RESULTS: The mean observation period was 2.5 years. Obesity, sarcopenic obesity, and dynapenic obesity were found in 271 (45.5%), 17 (2.9%), and 21 (3.5%) men, and 261 (44.7%), 59 (10.1%), and 53 (9.1%) women, respectively. A multivariate Cox proportional hazards model revealed that Child-Pugh class, dynapenia (hazard ratio [HR] 3.89), elderly (≥ 65 years old) (HR 2.11), and obesity (HR 0.58) were independently associated with overall survival (OS). However, neither sarcopenic nor dynapenic obesity were associated with OS. In patients with cirrhosis, the OS of the obese group was significantly higher than that of the non-obese group. The effect of obesity on OS was significant in elderly patients, but not in younger patients. CONCLUSIONS: Sarcopenic and dynapenic obesity seem unrelated to the prognosis of patients with chronic liver disease. Obesity has a positive effect on the prognosis of elderly patients with cirrhosis.

Impact of body mass index on long-term outcomes in patients undergoing percutaneous coronary intervention stratified by diabetes mellitus: a retrospective cohort study.

BACKGROUND: Patients with diabetes mellitus (DM) caused by obesity have increased in recent years. The impact of obesity on long-term outcomes in patients undergoing percutaneous coronary intervention (PCI) with or without DM remains unclear. METHODS: We retrospectively analysed data from 1918 patients who underwent PCI. Patients were categorized into four groups based on body mass index (BMI, normal weight: BMI < 25 kg/m2; overweight and obese: BMI ≥ 25 kg/m2) and DM status (presence or absence). The primary endpoint was the occurrence of major adverse cardiac and cerebrovascular events (MACCE; defined as all-cause death, myocardial infarction, stroke, and unplanned repeat revascularization). RESULTS: During a median follow-up of 7.0 years, no significant differences in MACCE, myocardial infarction, or stroke were observed among the four groups. Overweight and obese individuals exhibited lower all-cause mortality rates compared with normal-weight patients (without DM: hazard ratio [HR]: 0.54, 95% confidence interval [CI]: 0.37 to 0.78; with DM: HR: 0.57, 95% CI: 0.38 to 0.86). In non-diabetic patients, the overweight and obese group demonstrated a higher risk of unplanned repeat revascularization than the normal-weight group (HR:1.23, 95% CI:1.03 to 1.46). After multivariable adjustment, overweight and obesity were not significantly associated with MACCE, all-cause death, myocardial infarction, stroke, or unplanned repeat revascularization in patients with and without diabetes undergoing PCI. CONCLUSION: Overweight and obesity did not demonstrate a significant protective effect on long-term outcomes in patients with and without diabetes undergoing PCI.

Association between obesity paradox in the all-cause mortality among patients with cardiac resynchronization therapy device.

BACKGROUND: Recent studies have demonstrated an obesity paradox, where obese patients with cardiovascular disease have a better outcome compared to those with normal weight. However, the effect of obesity and body mass index (BMI) on the outcome of patients with cardiac resynchronization therapy (CRT) devices remains unclear. The current study aims to investigate this relationship using all available published data. METHODS: We systematically reviewed studies from Medline and EMBASE databases from inception to January 2024. Eligible studies must investigate the association between BMI status and all-cause mortality in individuals with CRT devices. Relative risk (RR) or hazard ratio (HR) and 95% CIs were retrieved from each study and combined using the generic inverse variance method. RESULTS: A total of 12 cohort studies were included in the meta-analysis. Pooled analysis showed that overweight and obesity patients had lower all-cause mortality compared to those with normal body weight with the pooled risk ratios (RR) for overweight of 0.77 (95% CI 0.69-0.87, I2 47%) and for obesity of 0.81 (95% CI 0.67-0.97, I2 59%). Conversely, the underweight exhibited higher all-cause mortality than the group with normal weight, with a pooled RR of 1.37 (95% CI 1.14-1.64, I2 0%). Additionally, higher BMI as continuous data was associated with decreased all-cause mortality, with a pooled HR of 0.94 (95% CI 0.89-0.98, I2 72%). CONCLUSIONS: The pooled analyses observed an obesity paradox in patients with CRT, where overweight and obesity were associated with reduced all-cause mortality, while underweight individuals exhibited higher all-cause mortality. Further research is necessary to investigate the underlying mechanisms and their implications for clinical practice.

Circulating level of ß-aminoisobutyric acid (BAIBA), a novel myokine-like molecule, is inversely associated with fat mass in patients with heart failure.

Results of experimental studies have shown that ß-aminoisobutyric acid (BAIBA), an exercise-induced myokine-like molecule, is an endogenous negative regulator of fat mass in mice, but it remains unclear whether that is the case in humans, though an enhanced BAIBA concentration in patients receiving sodium-glucose cotransporter 2 inhibitors was found in our recent study. The objective of this study was to analyze the determinants of circulating BAIBA concentration in humans, with focus on the possible link between circulating BAIBA and body composition including fat mass. Data for 188 consecutive patients with heart failure (HF, 64 ± 13 years; 70% male) who received a dual energy X ray absorptiometry (DEXA) scan for assessment of body composition including fat mass index (FMI) and appendicular skeletal muscle mass index (ASMI) were used in this study. Plasma BAIBA concentration in a fasting state after stabilization of HF was determined using ultraperformance liquid chromatography. Plasma BAIBA was detected in 66% of the patients. In simple linear regression analyses of data from patients in whom plasma BAIBA was detected, plasma BAIBA concentration was positively correlated with uric acid and was negatively correlated with body mass index (BMI), estimated glomerular filtration rate (eGFR), FMI, and % body fat. There were no correlations between plasma BAIBA concentration and indexes of muscle mass and bone mass. The results of multiple linear regression analyses showed that FMI and % body fat in addition to BMI, but not ASMI, were independent explanatory factors for plasma BAIBA concentration. In conclusion, plasma BAIBA concentration is inversely correlated with indexes of fat mass, indicating that BAIBA may be a therapeutic target for excessive fat accumulation.

Association of anthropometric measures with all-cause and cause-specific mortality in US adults: revisiting the obesity paradox.

OBJECTIVE: Previous studies have shown that the obesity paradox exists in a variety of clinical settings, whereby obese individuals have lower mortality than their normal-weight counterparts. It remains unclear whether the association between obesity and mortality risk varies by anthropometric measures. The purpose of this study is to examine the association between various anthropometric measures and all-cause and cause-specific mortality in US adults. METHODS: This cohort study included data from the National Health and Nutrition Examination Survey between 2009 and 2018, with a sample size of 28,353 individuals weighted to represent 231 million US adults. Anthropometric measurements were obtained by trained technicians using standardized methods. Mortality data were collected from the date of enrollment through December 31, 2019. Weighted Cox proportional hazards models, restricted cubic spline curves, and cumulative incidence analyses were performed. RESULTS: A total of 2091 all-cause deaths, 606 cardiovascular deaths, 519 cancer deaths, and 966 other-cause deaths occurred during a median follow-up of 5.9 years. The association between body mass index (BMI) and mortality risk was inversely J-shaped, whereas the association between waist-to-height ratio (WHtR) and mortality risk was positively J-shaped. There was a progressive increase in the association between the WHtR category and mortality risk. Compared with the reference category of WHtR < 0.5, the estimated hazard ratio (HR) for all-cause mortality was 1.004 (95% confidence interval [CI] 1.001-1.006) for WHtR 0.50-0.59, 1.123 (95% CI 1.120-1.127) for WHtR 0.60-0.69, 1.591 (95% CI 1.584-1.598) for WHtR 0.70-0.79, and 2.214 (95% CI 2.200-2.228) for WHtR ≥ 0.8, respectively. Other anthropometric indices reflecting central obesity also showed that greater adiposity was associated with higher mortality. CONCLUSIONS: Anthropometric measures reflecting central obesity were independently and positively associated with mortality risk, eliminating the possibility of an obesity paradox.

The impact of obesity on ventilator-associated pneumonia, a US nationwide study.

BACKGROUND: Ventilator-associated pneumonia (VAP) is one of the leading causes of mortality in patients with critical care illness. Since obesity is highly prevalent, we wanted to study its impact on the outcomes of patients who develop VAP. METHODS: Using the National Inpatient Sample (NIS) database from 2017 to 2020, we conducted a retrospective study of adult patients with a principal diagnosis of VAP with a secondary diagnosis with or without obesity according to 10th revision of the International Statistical Classification of Diseases (ICD-10) codes. Several demographics, including age, race, and gender, were analyzed. The primary endpoint was mortality, while the secondary endpoints included tracheostomy, length of stay in days, and patient charge in dollars. Multivariate logistic regression model analysis was used to adjust for confounders, with a p-value less than 0.05 considered statistically significant. RESULTS: The study included 3832 patients with VAP, 395 of whom had obesity. The mean age in both groups was around 58 years, and 68% of the group with obesity were females compared to 40% in females in the group without obesity. Statistically significant comorbidities in the obesity group included a Charlson Comorbidity Index score of three and above, diabetes mellitus, hypertension, chronic kidney disease, and sleep apnea. Rates and odds of mortality were not significantly higher in the collective obesity group 39 (10%) vs. 336 (8.5%), p-value 0.62, adjusted odds ratio 1.2, p-value 0.61). The rates and odds of tracheostomy were higher in the obesity group but not statistically significant. Obese patients were also found to have a longer hospitalization. Upon subanalysis of the data, no evidence of racial disparities was found in the care of VAP for both the obese and control groups. CONCLUSIONS: Obesity was not found to be an independent risk factor for worse outcomes in patients who develop VAP in the intensive care unit.

The Definition and Prevalence of Obesity and Metabolic Syndrome: Correlative Clinical Evaluation Based on Phenotypes.

Increase in the prevalence of obesity has become a major worldwide health problem in adults as well as among children and adolescents. In the last four decades, studies have revealed that the significant increase in the prevalence of obesity has become a pandemic. Obesity is the result of complex interactions between biological, genetic, environmental, and behavioral factors. Indeed, almost all of the children suffering from obesity in early childhood face with being overweight or obese in adolescence. Different phenotypes have different risk factors in the clinical evaluation of obesity. Individuals suffering from metabolically unhealthy obesity (MUO) are at an excess risk of developing cardiovascular diseases (CVDs), several cancer types, and metabolic syndrome (MetS), whereas the metabolically healthy obesity (MHO) phenotype has a high risk of all-cause mortality and cardiometabolic events but not MetS. While most obese individuals have the MUO phenotype, the frequency of the MHO phenotype is at most 10-20%. Over time, approximately three-quarters of obese individuals transform from MHO to MUO. Total adiposity and truncal subcutaneous fat accumulation during adolescence are positively and independently associated with atherosclerosis in adulthood. Obesity, in general, causes a large reduction in life expectancy. However, the mortality rate of morbid obesity is greater among younger than older adults. Insulin resistance (IR) develops with the central accumulation of body fat. MHO patients are insulin-sensitive like healthy normal-weight individuals and have lower visceral fat content and cardiovascular consequences than do the majority of MUO patients. MetS includes clustering of abdominal obesity, dyslipidemia, hyperglycemia, and hypertension. The average incidence of MetS is 3%, with a 1.5-fold increase in the risk of death from all causes in these patients. If lifestyle modifications, dietary habits, and pharmacotherapy do not provide any benefit, then bariatric surgery is recommended to reduce weight and improve comorbid diseases. However, obesity treatment should be continuous in obese patients by monitoring the accompanying diseases and their consequences. In addition to sodium-glucose co-transporter-2 (SGLT2) inhibitors, the long-acting glucagon-like peptide-1 (GLP-1) receptor agonist reduces the mean body weight. However, caloric restriction provides more favorable improvement in body composition than does treatment with the GLP-1 receptor (GLP1R) agonist alone. Combination therapy with orlistat and phentermine are the US Food and Drug Administration (FDA)-approved anti-obesity drugs. Recombinant leptin and synthetic melanocortin-4-receptor agonists are used in rarely occurring, monogenic obesity, which is due to loss of function in the leptin-melanocortin pathway.

The Unrestrained Overeating Behavior and Clinical Perspective.

Obesity-related co-morbidities decrease life quality, reduce working ability, and lead to early death. In the adult population, eating addiction manifests with excessive food consumption and the unrestrained overeating behavior, which is associated with increased risk of morbidity and mortality and defined as the binge eating disorder (BED). This hedonic intake is correlated with fat preference and the total amount of dietary fat consumption is the most potent risk factor for weight gain. Long-term BED leads to greater sensitivity to the rewarding effects of palatable foods and results in obesity fatefully. Increased plasma concentrations of non-esterified free fatty acids and lipid-overloaded hypertrophic adipocytes may cause insulin resistance. In addition to dietary intake of high-fat diet, sedentary lifestyle leads to increased storage of triglycerides not only in adipose tissue but also ectopically in other tissues. Lipid-induced apoptosis, ceramide accumulation, reactive oxygen species overproduction, endoplasmic reticulum stress, and mitochondrial dysfunction play role in the pathogenesis of lipotoxicity. Food addiction and BED originate from complex action of dopaminergic, opioid, and cannabinoid systems. BED may also be associated with both obesity and major depressive disorder. For preventing morbidity and mortality, as well as decreasing the impact of obesity-related comorbidities in appropriately selected patients, opiate receptor antagonists and antidepressant combination are recommended. Pharmacotherapy alongside behavioral management improves quality of life and reduces the obesity risk; however, the number of licensed drugs is very few. Thus, stereotactic treatment is recommended to break down the refractory obesity and binge eating in obese patient. As recent applications in the field of non-invasive neuromodulation, transcranial magnetic stimulation and transcranial direct current stimulation are thought to be important in image-guided deep brain stimulation in humans. Chronic overnutrition most likely provides repetitive and persistent signals that up-regulate inhibitor of nuclear factor kappa B (NF-κB) kinase beta subunit/NF-κB (IKKß/NF-κB) in the hypothalamus before the onset of obesity. However, how the mechanisms of high-fat diet-induced peripheral signals affect the hypothalamic arcuate nucleus remain largely unknown.

Obesity Paradox in Transcatheter Aortic Valve Replacement.

BACKGROUND: Obesity paradox in cardiovascular risk prediction has gained increasing attention in recent years. We aimed to investigate the impact of BMI on mortality following transcatheter aortic valve replacement (TAVR). METHODS: We performed a multi-center retrospective analysis of patients with severe aortic stenosis undergoing TAVR. Patients were categorized into: Underweight (BMI < 18.5), normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30) and obese (BMI ≥ 30). Multivariate cox-proportional hazard model was used to compare all-cause mortality. RESULTS: Total of 6688 patients included (175 underweight, 2252 normal weight, 2368 overweight and 1893 with obesity). Mean age of patients was 81 ± 8 years with 55% males. Patients with obesity had higher prevalence of comorbidities but a lower overall STS score. Mortality at 30-days post-TAVR was lower in the obese population compared to underweight, normal weight, and overweight patients (1.6% vs. 6.9%, 3.6%, and 2.8%, respectively, p < 0.001). Similarly, 3-year mortality was lowest in patients with obesity (17.1% vs. 28.9%, 24.5% and 18.6%, respectively, p < 0.001). On multivariate analysis, long term all-cause mortality at 3-years remained significantly lower in patients with obesity compared to underweight (HR 1.74, 95% CI: 1.30-2.40, p < 0.001) and normal weight (HR: 1.41, 95% CI:1.21-1.63, p < 0.001) but not in overweight patients (HR: 1.10, 95% CI:0.94-1.28, p = 0.240). CONCLUSION: In conclusion, patients with obesity have improved short and long term mortality following TAVR with an observed progressive increase in mortality with lower BMI ranges.

The Influence of Body Mass Index on Outcomes in Patients Undergoing Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion: Institutional Experience and Meta-analysis.

BACKGROUND: An obesity paradox, whereby patients with higher body mass index (BMI) experience improved outcomes, has been described for ischemic stroke. It is unclear whether this applies to patients undergoing mechanical thrombectomy (MT) for large vessel occlusion (LVO). METHODS: Mechanical thrombectomies for anterior circulation LVO between 2015 and 2021 at a single institution were reviewed. Multivariable logistic regressions were used to determine the association between BMI and favorable functional outcome (90-day modified Rankin Scale 0-2), intracranial hemorrhage, and malignant middle cerebral infarction. A systematic review was performed to identify studies reporting the effect of BMI on outcomes among patients receiving MT for LVO. The data from the systematic review were combined with the institutional data by using a random effects model. RESULTS: The institutional cohort comprised 390 patients with a median BMI of 27 kg/m2. Most patients were obese [36.7% (BMI ≥ 30 kg/m2)], followed by overweight [30.5% (BMI ≥ 25 and < 30 kg/m2)], normal [27.9% (BMI ≥ 18.5 and < 25 kg/m2)], and underweight [4.9% (BMI < 18.5 kg/m2)]. As a continuous variable, BMI was not associated with any of the outcomes. When analyzing BMI ordinally, obesity was associated with lower odds of favorable 90-day modified Rankin Scale (odds ratio 0.42, 95% confidence interval 0.20-0.86). The systematic review identified three eligible studies comprising 1,348 patients for a total of 1,738 patients. In the random effects model, there was no association between obesity and favorable outcome (odds ratio 0.89, 95% confidence interval 0.63-1.24). CONCLUSIONS: Obesity is not associated with favorable outcomes in patients undergoing MT for LVO.

The Effect of Body Mass Index on Melanoma Biology, Immunotherapy Efficacy, and Clinical Outcomes: A Narrative Review.

Recent studies indicate that a higher body mass index (BMI) might correlate with improved responses to melanoma treatment, especially with immune checkpoint inhibitors (ICIs), despite the general association of obesity with an increased risk of cancer and higher mortality rates. This review examines the paradoxical relationship between BMI and clinical outcomes in melanoma patients by exploring molecular links, the efficacy of immunotherapy, and patient survival outcomes. Our comprehensive literature search across the PubMed and Embase databases revealed a consistent pattern: increased BMI is associated with a better prognosis in melanoma patients undergoing ICI treatment. This "obesity paradox" might be explained by the metabolic and immunological changes in obesity, which could enhance the effectiveness of immunotherapy in treating melanoma. The findings highlight the complexity of the interactions between obesity and melanoma, suggesting that adipose tissue may modulate the immune response and treatment sensitivity favorably. Our review highlights the need for personalized treatment strategies that consider the metabolic profiles of patients and calls for further research to validate BMI as a prognostic factor in clinical settings. This nuanced approach to the obesity paradox in melanoma could significantly impact treatment planning and patient management.

A Nonlinear Relation between Body Mass Index and Long-Term Poststroke Functional Outcome-The Importance of Insulin Resistance, Inflammation, and Insulin-like Growth Factor-Binding Protein-1.

Both high serum insulin-like growth factor-binding protein-1 (s-IGFBP-1) and insulin resistance (IR) are associated with poor functional outcome poststroke, whereas overweight body mass index (BMI; 25-30) is related to fewer deaths and favorable functional outcome in a phenomenon labeled "the obesity paradox". Furthermore, IGFBP-1 is inversely related to BMI, in contrast to the linear relation between IR and BMI. Here, we investigated s-IGFBP-1 and IR concerning BMI and 7-year poststroke functional outcome. We included 451 stroke patients from the Sahlgrenska Study on Ischemic Stroke (SAHLSIS) with baseline measurements of s-IGFBP1, homeostasis model assessment of IR (HOMA-IR), BMI (categories: normal-weight (8.5-25), overweight (25-30), and obesity (>30)), and high-sensitivity C-reactive protein (hs-CRP) as a measure of general inflammation. Associations with poor functional outcome (modified Rankin scale [mRS] score: 3-6) after 7 years were evaluated using multivariable binary logistic regression, with overweight as reference due to the nonlinear relationship. Both normal-weight (odds-ratio [OR] 2.32, 95% confidence interval [CI] 1.30-4.14) and obese (OR 2.25, 95% CI 1.08-4.71) patients had an increased risk of poor functional outcome, driven by deaths only in the normal-weight. In normal-weight, s-IGFBP-1 modestly attenuated (8.3%) this association. In the obese, the association was instead attenuated by HOMA-IR (22.4%) and hs-CRP (10.4%). Thus, a nonlinear relation between BMI and poor 7-year functional outcome was differently attenuated in the normal-weight and the obese.

Fat but Fit: How physical fitness can mitigate the cardiovascular risks of obesity?

Obesity has long been recognized as a major independent risk factor for cardiovascular diseases (CVD). However, intriguing paradoxes such as the "obesity paradox" and the "fat but fit" phenomenon have been associated with it. The "fat but fit" paradigm suggests that overweight or obese individuals might face a lower risk of developing cardiovascular disease if they possess high levels of physical fitness. In other words, higher fitness levels may mitigate the negative impact of obesity on cardiovascular risk, leading to a reduction in overall mortality due to CVD. The evidence surrounding this paradox is conflicting, highlighting the necessity for further research. The complex relationship between physical fitness, obesity, and cardiometabolic health is influenced by individual and environmental factors. Consequently, it becomes imperative to conduct more studies to comprehend this intricate interplay fully. To address this issue, it is important to focus on formulating strategies that promote the maintenance and enhancement of cardiorespiratory fitness in overweight and obese individuals. Moreover, including fitness evaluations in comprehensive risk stratification can significantly improve clinical decision-making.

Usefulness of the preoperative inflammation-based prognostic score and the ratio of visceral fat area to psoas muscle area on predicting survival for surgically resected adenocarcinoma of the esophagogastric junction.

BACKGROUND: Sarcopenic obesity is associated with gastrointestinal cancer prognosis through systemic inflammation. However, in patients with adenocarcinoma of the esophagogastric junction (AEG), the relationship between the inflammation-based prognostic score (IBPS), muscle loss, visceral fat mass, and prognosis has not been sufficiently evaluated. We investigated the prognostic value of the preoperative IBPS and the visceral fat area ratio to the psoas muscle area (V/P ratio) in patients with AEG undergoing surgery. METHODS: We retrospectively analyzed 92 patients with AEG who underwent surgery. The prognostic value of the preoperative neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio, systemic inflammation response index, C-reactive protein-to-albumin ratio, prognostic nutritional index, modified Glasgow Prognostic Score, and V/P ratio at the third lumbar vertebra was investigated using univariate and multivariate survival analyses. RESULTS: Multivariate analysis revealed that a high pathological stage (p = 0.0065), high PLR (p = 0.0421), and low V/P ratio (p = 0.0053) were independent prognostic factors for poor overall survival (OS). When restricted to patients with body mass index (BMI) ≥ 25 kg/m2, a high V/P ratio was a poor prognostic factor (p = 0.0463) for OS. Conversely, when restricted to patients with BMI < 25 kg/m2, a low V/P ratio was a poor prognostic factor (p = 0.0021) for OS. CONCLUSIONS: Both PLR and V/P ratios may be useful prognostic biomarkers in surgical cases of AEG. V/P ratio and BMI may provide an accurate understanding of the muscle and fat mass's precise nature and may help predict AEG prognosis.

Obesity impacts hypoxia adaptation of the lung.

Obesity is mostly associated with adverse health consequences, but may also elicit favorable effects under chronic conditions. This "obesity paradox" is under debate for pulmonary diseases. As confounding factors complicate conclusions from human studies, this study used a controlled animal model combining diet-induced obesity and chronic hypoxia as a model for pulmonary hypertension and chronic obstructive pulmonary disease. Male C57BL/6 mice were fed control or high-fat diet for 30 wk, and half of the animals were exposed to chronic hypoxia (13% O2) for 3 wk. Hypoxia induced right ventricular hypertrophy, thickening of pulmonary arterial and capillary walls, higher lung volumes, and increased hemoglobin concentrations irrespective of the body weight. In contrast, lung proteomes differed substantially between lean- and obese-hypoxic mice. Many of the observed changes were linked to vascular and extracellular matrix (ECM) proteins. In lean-hypoxic animals, circulating platelets were reduced and abundances of various clotting-related proteins were altered, indicating a hypercoagulable phenotype. Moreover, the septal ECM composition was changed, and airspaces were significantly distended pointing to lung hyperinflation. These differences were mostly absent in the obese-hypoxic group. However, the obesity-hypoxia combination induced the lowest blood CO2 concentrations, indicating hyperventilation for sufficient oxygen supply. Moreover, endothelial surface areas were increased in obese-hypoxic mice. Thus, obesity exerts differential effects on lung adaptation to hypoxia, which paradoxically include not only adverse but also rather protective changes. These differences have a molecular basis in the lung proteome and may influence the pathogenesis of lung diseases. This should be taken into account for future individualized prevention and therapy.NEW & NOTEWORTHY An "obesity paradox" is discussed for pulmonary diseases. By linking lung proteome analyses to pulmonary structure and function, we demonstrate that diet-induced obesity affects lung adaptation to chronic hypoxia in various ways. The observed changes include not only adverse but also protective effects and are associated with altered abundances of vascular and extracellular matrix proteins. These results highlight the existence of relevant differences in individuals with obesity that may influence the pathogenesis of lung diseases.

A comparison of analytic approaches for investigating the obesity paradox in kidney cancer.

PURPOSE: Body mass index (BMI) and kidney cancer mortality are inconsistently associated in the scientific literature. To understand how study design affects results, we contrasted associations between pre-diagnosis BMI and mortality under different analytic scenarios in a large, population-based prospective cohort study. METHODS: Using data from the NIH-AARP Diet and Health Study (1995-2011), we constructed two cohorts: a "full at-risk" cohort with no kidney cancer history at baseline (n = 252,845) and an "incident cancer" subset who developed kidney cancer during follow-up (n = 1,652). Cox Proportional Hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) between pre-diagnosis BMI and mortality for different outcomes (all-cause and cancer-specific mortality), in the different cohorts (full at-risk vs. incident cancer cohort), and with different covariates (minimally vs. fully adjusted). For the incident cancer cohort, we also examined time to mortality using different timescales: from enrollment or diagnosis. RESULTS: In the full at-risk study population, higher pre-diagnosis BMI was associated with greater cancer-specific mortality in fully adjusted multivariable models, particularly for obese participants [HR, (95% CI): 1.76, (1.38-2.25)]. This association was less pronounced in the incident cancer cohort [1.50, (1.09-2.07)]. BMI was not strongly associated with all-cause mortality in either cohort in fully adjusted models [full cohort: 1.03, (1.01, 1.06); incident cancer cohort: 1.20, (0.97, 1.48)]. CONCLUSIONS: Populations characterized by high adult BMI will likely experience greater population burdens of mortality from kidney cancer, partially because of higher rates of kidney cancer diagnosis. Questions regarding overall mortality burden and post-diagnosis cancer survivorship are distinct and require different study designs.

Association of body mass index and long-term mortality in patients from nationwide LIPIDOGRAM 2004-2015 cohort studies: no obesity paradox?

BACKGROUND: An obesity paradox has been described in relation to adverse clinical outcomes (e.g., mortality) with lower body mass index (BMI). AIMS: We sought to evaluate the association between BMI and weight loss with long-term all-cause mortality in adult populations under the care of family physicians. METHODS: LIPIDOGRAM studies were conducted in primary care in Poland in 2004, 2006, and 2015 and enrolled a total of 45,615 patients. The LIPIDOGRAM Plus study included 1627 patients recruited in the LIPIDOGRAM 2004 and repeated measurements in 2006 edition. Patients were classified by BMI categories as underweight, normal weight, overweight and class I, II, or III (obesity). Follow-up data up to December 2021 were obtained from the Central Statistical Office. Differences in all-cause mortality were analyzed using Kaplan‒Meier and Cox regression analyses. RESULTS: Of 45,615 patients, 10,987 (24.1%) were normal weight, 320 (0.7%) were underweight, 19,134 (41.9%) were overweight, and 15,174 (33.2%) lived with obesity. Follow-up was available for 44,620 patients (97.8%, median duration 15.3 years, 61.7% females). In the crude analysis, long-term all-cause mortality was lowest for the normal-weight group (14%) compared with other categories. After adjusting for comorbidities, the highest risk of death was observed for the class III obesity and underweight categories (hazard ratio, HR 1.79, 95% CI [1.55-2.05] and HR 1.57, 95% CI [1.22-2.04]), respectively. The LIPIDOGRAM Plus analysis revealed that a decrease in body weight (by 5 and 10%) over 2 years was associated with a significantly increased risk of death during long-term follow-up-HR 1.45 (95% CI 1.05-2.02, p = 0.03) and HR 1.67 (95% CI 1.02-2.74, p < 0.001). Patients who experienced weight loss were older and more burdened with comorbidities. CONCLUSIONS: Being underweight, overweight or obese is associated with a higher mortality risk in a population of patients in primary care. Patients who lost weight were older and more burdened with cardiometabolic diseases, which may suggest unintentional weight loss, and were at higher risk of death in the long-term follow-up. In nonsmoking patients without comorbidities, the lowest mortality was observed in those with a BMI < 25 kg/m2, and no U-curve relationship was observed.