Effect of body mass index on the outcome of infections: a systematic review

Health Implications Associated with Fat-Free Mass: A Phenome-Wide Mendelian Randomization Study

INTRODUCTION

Fat-free mass (FFM) is a critical component of the human body, with implications for various diseases.

METHODS

We conducted a comprehensive analysis integrating a phenome-wide association study (PheWAS), a two-sample Mendelian randomization (MR) analysis, and a systematic review to investigate the associations between FFM and health outcomes.

RESULTS

PheWAS identified 183 phenotypes enriched for FFM associations, including diseases, body composition, and lifestyle factors. A two-sample MR analysis using the FinnGen and UK Biobank dataset revealed significant associations between genetically determined FFM and 36 disease outcomes, including cardiovascular diseases, metabolic disorders, and musculoskeletal conditions. The mediation MR analysis indicates that FFM indirectly influences the levels of five biomarkers in visceral adipose tissue. A systematic review identified consistent associations between FFM and several diseases, including type 2 diabetes and cervical disc disorders. Moreover, new associations such as low back pain and ovarian cancer were discovered.

CONCLUSION

These findings challenge the conventional notion of FFM as a protective factor in health, suggesting that higher FFM levels may be linked to an increased risk of various diseases. Further clinical studies are warranted to validate these findings and elucidate the underlying mechanisms.

The association between undetected heteroresistance and antibiotic treatment failure in complicated urinary tract infection

Background

Antibiotic resistance is a worsening public health threat. One poorly understood aspect of this problem is unexpected antibiotic treatment failure; when an infecting isolate is deemed susceptible to a given antibiotic, yet treatment with that drug fails. It has been proposed that heteroresistance may be an explanation for at least some unexplained treatment failures. Heteroresistance occurs when a bacterial isolate harbors a minor subpopulation of resistant cells which coexists with a majority susceptible population. The clinical relevance of heteroresistance is not clear.

Methods

We obtained 291 index isolates from 288 unique patients in the piperacillin/tazobactam arm of the ALLIUM phase 3 clinical trial for the treatment of Gram-negative pathogens causing complicated urinary tract infections. The MIC for all isolates was below the piperacillin/tazobactam resistance breakpoint according to standard antimicrobial susceptibility testing. We performed population analysis profiles on these isolates to detect piperacillin/tazobactam heteroresistance and conducted a post hoc analysis to examine the impact of heteroresistance on clinical outcomes.

Findings

We observed that 33/288 (11.5%) of the patients were infected with isolates that were heteroresistant to piperacillin/tazobactam and that patients infected with heteroresistant isolates had an increased rate of treatment failure when compared to patients infected with a non-heteroresistant isolate (odds ratio [OR] 2.13, 95% CI 1.02, 4.41; adjusted OR 1.74, 95% CI 0.82, 3.71). Further, patients without a removable catheter were at particular risk of treatment failure from infection with heteroresistant isolates.

Interpretation

These data demonstrate that patients infected with a piperacillin/tazobactam heteroresistant isolate are at an increased risk for piperacillin/tazobactam treatment failure. The results help contextualize commonly observed unexpected antibiotic treatment failure and highlight heteroresistance as a potential cause.

Comparison of surgical wound infection and dehiscence following the use of two methods of nylon sutures and skin staples in staples in diabetic mellitus patients undergoing total knee arthroplasty surgery: a randomized clinical trial study

OBJECTIVE

Timely and complete surgical wound healing substantially affects the patient's performance and satisfaction with surgery outcomes. Sutures and staples are two common wound closure methods in total knee arthroplasty; however, their role in reducing the rate of surgical wound infections and dehiscence in diabetic patients is unclear. Therefore, this study was conducted to investigate the rate of infection and post-closure dehiscence in wounds closed with either nylon sutures or skin staples in diabetic patients undergoing total knee arthroplasty (TKA).

METHODS

This is a single-blind randomized clinical trial including 70 diabetic mellitus patients undergoing TKA. Patients were selected using a restricted random sampling method and haphazardly assigned to study groups using the permuted block randomization technique, including the suture-closed (n = 35) and staple-closed (n = 35) groups. The follow-up was 2 to 8 weeks after the surgery, evaluation of wound infection and dehiscence was performed.

RESULTS

The present study showed that there was no significant correlation between wound infection rate (P-value = 0.254) and wound dehiscence (P-value = 0.324) with the method of wound closure (i.e., sutures or staples). However, surgical wound dehiscence revealed a significant correlation with body mass index (BMI) (P-value = 0.044), Glycosylated hemoglobin (HbA1c) (P-Value = 0.001), and fasting blood glucose (FBS) (P-Value = 0.012) in diabetic mellitus patients.

CONCLUSION

The use of the staple technique compared to suture had no difference in the rate of wound opening and infection, but from a clinical point of view, the prevalence of wound opening after TKA in patients with the suture method was higher than that of staples. Further research is needed to confirm these findings and the long-term efficacy of each method.

CLINICAL TRIAL REGISTRATION

The present study was registered at the Iranian Registry of Clinical Trails (No. IRCT20230928059543N1, Trial Id:74754, approved on 12/01/2024, https://irct.behdasht.gov.ir/user/trial/74754/view ) and conducted according to Consolidated Standards of Reporting Trials (CONSORT) guidelines.

Evaluation and implementation of optimized antimicrobial dosing strategies in obese and underweight patients

PURPOSE

We aimed to develop and implement dosing recommendations for antimicrobials in obese and underweight patients within an academic hospital, and assess their impact on antibiotic prescribing.

METHODS

A multi-step approach project was performed. First, obese and underweight patient prevalence and antimicrobial prescription frequency was determined in a point prevalence study. Second and third, a literature review and e-survey provided dosing evidence. Fourth, a consensus meeting was organized to formulate dosing recommendations. Fifth, these were implemented in our clinical validation service as six clinical rules continuously screening patients' records for potentially inappropriate prescriptions (PIPs). Uptake was evaluated by documenting the number of advices and acceptance rate. Last, an interrupted time series analysis (ITS) compared pre- and post-implementation periods to measure the impact of the intervention on residual PIPs/day. A residual PIP was defined as a PIP which persisted up to 48 h.

RESULTS

First, 41% of 15.896 hospitalized patients received antimicrobials over 20 days; of which 12% were obese and 9% underweight. Antibiotics were predominantly prescribed according to standard dosing regimens, adjusted to renal function. Next, six dosing recommendations, derived from literature, survey, and consensus, were implemented. In the fifth step, during an 18-week period, 219 advices were given, with 86% acceptance rate. Last, in the ITS analysis, at preintervention, a median of 75% residual PIPs/day existed, reduced to 0% postintervention. Use of clinical rules resulted in a significant immediate 84% relative reduction in residual PIPs (95% CI 0.55-0.94).

CONCLUSION

After conducting a literature review, e-survey, and seeking consensus from a panel of experts, dosing recommendations for antimicrobial treatment in both obese and underweight patients were developed. These recommendations have been successfully implemented into clinical practice, addressing the specific needs of these patient populations.

Efficacy of Ciprofloxacin in Treating Gram-Negative Infections: Does Obesity Matter?

BACKGROUND

Obesity is considered a health issue associated with increased morbidity and a risk factor for multiple conditions, such as type 2 diabetes, cardiovascular diseases and infections. It may affect the pharmacokinetics and pharmacodynamics of many drugs, including antimicrobials like ciprofloxacin. Regrettably, data on ciprofloxacin's efficacy in obese patients remain scarce. This study aims to evaluate the impact of obesity on the efficacy of ciprofloxacin in treating Gram-negative bacterial infections.

METHODS

A retrospective multicenter cohort study was conducted in two tertiary hospitals in Saudi Arabia. Adult patients (≥18 years) treated with ciprofloxacin for confirmed Gram-negative infection between January 2017 and April 2023 were included. Patients were excluded if they received ciprofloxacin empirically, had inadequate source control within 72 h, or had missing weight and height information at ciprofloxacin initiation. The primary outcome was clinical cure, defined as the resolution of the clinical infection manifestations without additional therapeutic management by the end of treatment. Other secondary and safety outcomes were also assessed.

RESULTS

A total of 99 patients were included, divided into obese (n = 42) and non-obese (n = 57) groups. The obese group had a significantly lower median age (50 years) compared to the non-obese group (64 years) (p = 0.002). The obese group had fewer male patients (38.10% vs. 68.42%; p = 0.004), higher body weight (90 (81-97) vs. 63 (55-70) days; p < 0.001), and lower height (158 (155-165) vs. 165 (158-172) days; p = 0.008) compared to non-obese. Urinary tract infection was the most common type, with Escherichia coli being the most common isolate. The median hospital length of stay was shorter in the obese group than in the non-obese group (1 vs. 3 days, p = 0.007). There were no significant differences in clinical cure rates between obese (85.71%) and non-obese (85.96%) patients (p = 1). No significant differences were observed in terms of in-hospital mortality, 30-day mortality, or 60-day infection recurrence rates between the two groups. Microbiological eradication was not achieved in the obese group, whereas a 10.53% eradication rate was observed in the non-obese group (p = 0.037). However, the majority of the patients had indeterminate eradication. The incidence of adverse drug reactions (ADRs) was lower in the obese group (4.76%) compared to the non-obese group (17.54%, p = 0.066).

CONCLUSIONS

Treatment with ciprofloxacin in obese patients has similar efficacy and safety outcomes compared to non-obese patients with infections due to Gram-negative pathogens.

The chemerin-CMKLR1 axis in keratinocytes impairs innate host defense against cutaneous Staphylococcus aureus infection

The skin is the most common site of Staphylococcus aureus infection, which can lead to various diseases, including invasive and life-threatening infections, through evasion of host defense. However, little is known about the host factors that facilitate the innate immune evasion of S. aureus in the skin. Chemerin, which is abundantly expressed in the skin and can be activated by proteases derived from S. aureus, has both direct bacteria-killing activity and immunomodulatory effects via interactions with its receptor CMKLR1. Here, we demonstrate that a lack of the chemerin/CMKLR1 axis increases the neutrophil-mediated host defense against S. aureus in a mouse model of cutaneous infection, whereas chemerin overexpression, which mimics high levels of chemerin in obese individuals, exacerbates S. aureus cutaneous infection. Mechanistically, we identified keratinocytes that express CMKLR1 as the main target of chemerin to suppress S. aureus-induced IL-33 expression, leading to impaired skin neutrophilia and bacterial clearance. CMKLR1 signaling specifically inhibits IL-33 expression induced by cell wall components but not secreted proteins of S. aureus by inhibiting Akt activation in mouse keratinocytes. Thus, our study revealed that the immunomodulatory effect of the chemerin/CMKLR1 axis mediates innate immune evasion of S. aureus in vivo and likely increases susceptibility to S. aureus infection in obese individuals.

Analysis of overweight/obese pediatric patients with acute myeloid leukemia: a report from the Japanese Pediatric Leukemia/Lymphoma Study Group AML-05 study

The dosage of chemotherapy drugs for overweight/obese children with acute myeloid leukemia (AML) has been empirically reduced based on ideal body weight (BW) in Japan to reduce the risk of adverse events. We investigated the associations between pre-therapeutic body mass index (BMI) and clinical outcomes among children with AML. A total of 280 children were divided into two groups based on the World Health Organization Child Growth Standards: a healthy-weight group (n = 254), and an overweight/obese group (n = 26). If BW exceeded 1.2 times the standard BW of Japanese children, the dosage of chemotherapy drugs was calculated using 1.2 times the standard BW. The dosage of chemotherapy drugs was reduced during at least one chemotherapy cycle in 24 of 26 patients (92.3%) in the overweight/obese group, compared with zero patients in the healthy-weight group. Overall/event-free survival, cumulative incidence of relapse, and treatment-related mortality (TRM) did not differ between the overweight/obese and healthy weight groups. However, the frequency of bacteremia was higher in the overweight/obese group (80.8 vs. 52.4%, P = 0.006). This indicates that TRM may increase when chemotherapy drug dosage is not corrected in overweight/obese patients. Drug reduction is a potential treatment strategy.

Factors affecting the changes in body mass index among emergency workers at the Fukushima Daiichi Nuclear Power Plant

Understanding the effects of lifestyle and radiation on health is important for the health management of disaster recovery workers. International research has demonstrated the relationship between natural disasters and diseases. The lifestyle and working conditions following the Great East Japan Earthquake potentially increased the incidence of cardiovascular disease and obesity among affected individuals. The aim of this study was to analyze the body mass index (BMI) of 1,341 emergency workers who responded to the accident at the Fukushima Daiichi Nuclear Power Plant. The BMI of each emergency worker was measured immediately after the accident and compared with that measured at the initial survey conducted 5 yr later to determine the effect of lifestyle habits on BMI. Awareness of the frequency of eating out and caloric intake helped maintain their BMI, while evacuation contributed to the increase in BMI. Prevention of obesity, which can trigger or exacerbate certain health conditions, such as heat exhaustion, infection, and cerebro-cardiovascular disease, requires diet counseling, with a focus on maintaining adequate caloric intake; moreover, special consideration should be provided to evacuated workers.

Obesity and its Relationship with Covid-19: A Review of the Main Pharmaceutical Aspects

Important physiological changes are observed in patients with obesity, such as intestinal permeability, gastric emptying, cardiac output, and hepatic and renal function. These differences can determine variations in the pharmacokinetics of different drugs and can generate different concentrations at the site of action, which can lead to sub therapeutic or toxic concentrations. Understanding the physiological and immunological processes that lead to the clinical manifestations of COVID-19 is essential to correlate obesity as a risk factor for increasing the prevalence, severity, and lethality of the disease. Several drugs have been suggested to control COVID- 19 like Lopinavir, Ritonavir, Ribavirin, Sofosbuvir, Remdesivir, Oseltamivir, Oseltamivir phosphate, Oseltamivir carboxylate, Hydroxychloroquine, Chloroquine, Azithromycin, Teicoplanin, Tocilizumab, Anakinra, Methylprednisolone, Prednisolone, Ciclesonide and Ivermectin. Similarly, these differences between healthy people and obese people can be correlated to mechanical factors, such as insufficient doses of the vaccine for high body mass, impairing the absorption and distribution of the vaccine that will be lower than desired or can be linked to the inflammatory state in obese patients, which can influence the humoral immune response. Additionally, different aspects make the obese population more prone to persistent symptoms of the disease (long COVID), which makes understanding these mechanisms fundamental to addressing the implications of the disease. Thus, this review provides an overview of the relationship between COVID-19 and obesity, considering aspects related to pharmacokinetics, immunosuppression, immunization, and possible implications of long COVID in these individuals.

Weighing the Odds: Novel β-Lactam/β-Lactamase Inhibitor Use in Hospital-Acquired and Ventilator-Associated Pseudomonas aeruginosa Pneumonia for Patients Who Are Morbidly Obese

Background

Pseudomonas aeruginosa is a leading cause of hospital-acquired and ventilator-associated bacterial pneumonia (HABP/VABP). Novel β-lactam/β-lactamase inhibitor (BL/BLI) combinations are often used for these infections; however, limited data exist to guide the dosing of BL/BLI in patients who are morbidly obese. Thus, we sought to evaluate the clinical and safety endpoints of patients who are morbidly obese (body mass index ≥35 kg/m2) and non-morbidly obese (<35 kg/m2) and receiving BL/BLI for P aeruginosa HABP/VABP.

Methods

This retrospective study was based on a cohort of patients hospitalized at 2 urban academic medical centers in Detroit, Michigan, from August 2014 through February 2021 with P aeruginosa HABP/VABP who were receiving BL/BLI (ceftazidime/avibactam, ceftolozane/tazobactam, or meropenem/vaborbactam) for ≥72 continuous hours. The primary endpoint was presumed treatment failure, defined as the presence of all-cause in-hospital mortality or the continuation of infectious symptoms. Analyses were adjusted for possible confounding with inverse probability of treatment weighting. Multivariable regression was used to identify predictors of treatment failure.

Results

In total, 285 patients with HABP (61.4%) and/or VABP (56.1%) were enrolled (morbidly obese, n = 95; non-morbidly obese, n = 190). The median Acute Physiology and Chronic Health Evaluation II score was 23 (IQR, 13-26), and 60% of patients were admitted to the intensive care unit at index culture collection. Patients who were morbidly obese demonstrated significantly greater odds of presumed treatment failure vs those who were non-morbidly obese (58.9% vs 37.9%, respectively; adjusted odds ratio, 1.675 [95% CI, 1.465-1.979]). In multivariable analysis, morbid obesity (1.06; 95% CI, 1.02-1.79), prolonged time to BL/BLI initiation (1.47; 95% CI, 1.28-2.66), renal dose-adjusted BL/BLI in the first 48 hours of therapy (1.12; 95% CI, 1.09-1.75), and continuous renal replacement therapy during BL/BLI therapy (1.35; 95% CI, 1.06-1.68) were independently associated with increased odds of presumed treatment failure.

Conclusions

Among hospitalized patients receiving BL/BLI for P aeruginosa HABP/VABP, those who were morbidly obese had significantly greater odds of presumed treatment failure when compared with those who were non-morbidly obese.

An RNA-immunoprecipitation via CRISPR/dCas13 reveals an interaction between the SARS-CoV-2 5'UTR RNA and the process of human lipid metabolism

We herein elucidate the function of SARS-CoV-2derived 5'UTR in the human cells. 5'UTR bound host cellular RNAs were immunoprecipitated by gRNA-dCas13 (targeting luciferase RNA fused to SARS-CoV-2 5'UTR) in HEK293T and A549 cells. The 5'UTR bound RNA extractions were predominantly enriched for regulating lipid metabolism. Overexpression of SARS-CoV-2 5'UTR RNA altered the expression of factors involved in the process of the human Mevalonate pathway. In addition, we found that HMG-CoA reductase inhibitors were shown to suppress SARS-CoV-2 5'UTR-mediated translation activities. In conclusion, we deduce the array of host RNAs interacting with SARS-CoV-2 5'UTR that drives SARS-CoV-2 translation and influences host metabolic pathways.

Insufficient Representation of Patients With Obesity in Randomized Controlled Trials Evaluating the Efficacy and Safety of Antimicrobials for Treatment of Skin and Skin Structure Infections: A Scoping Review

Persons with obesity (PwO) represent approximately 50% of acute bacterial skin and skin structure infections (ABSSSIs) in the United States (US). There are currently insufficient data in PwO for drugs used for ABSSSIs. We conducted a scoping review of randomized controlled trials (RCTs) published between 2000 and 2022 to describe how frequently body size measures were reported. Weight and/or body mass index (BMI) were recorded in approximately 50% of the 69 RCTs. The average weights or BMIs were lower than US averages for most RCTs reporting data. None evaluated the impact of body size on outcomes in the original publication. Only 30% of newly approved drugs mention PwO representation in the prescribing information. More representative recruitment of PwO into RCTs is needed to help clinicians evaluate efficacy in these patients. We suggest that the Food and Drug Administration require companies to submit plans to ensure adequate PwO inclusion and that authors of RCTs report subgroup results based on body size.

Risk assessment of postoperative pneumonia in children with neurologic disorders and obesity

INTRODUCTION

Postoperative pneumonia increases the risk of postsurgical mortality, making it a serious healthcare-associated complication. Children with preoperative neuromuscular impairments have a higher risk of postoperative pneumonia. Obesity is also a risk factor for postoperative pulmonary complications, including pneumonia. Moreover, obesity is increasingly prevalent among children living with a neurological diagnosis. Whether obesity increases the risk of postoperative pneumonia among children with neurologic diseases remains largely unknown. Therefore, we assessed the risk of postoperative pneumonia among children with neurologic diagnoses based on their obesity status.

METHODS

We analyzed a retrospective cohort of children ≤18 years from the National Surgical Quality Improvement Program (2012-2019) database who underwent inpatient orthopedic surgery. We used Cox proportional regression model to estimate the hazard ratio for the association between neurologic disorders and postoperative pneumonia. In addition, we included an interaction term between body mass index and neurologic disorders to evaluate the moderating effect of obesity status and then performed stratified analyses to compare the magnitude of hazard ratios across body mass index subgroups.

RESULTS

A total of 60 745 children underwent inpatient orthopedic surgery during the study period, of whom 43.6% were healthy weight and 30.8% overweight/obese. The median age was 13 years (Interquartile range: 8-15). The incidence of postoperative pneumonia was higher among healthy weight patients with neurologic disorders than healthy weight patients without any neurologic disorders [Hazard ratio: 3.55 vs. 0.34]. Furthermore, the association between neurologic disorders and postoperative pneumonia was strongest among overweight patients than healthy weight or obese patients [Hazard ratio:11.88 vs. 9.45 vs. 4.40]. This observation was consistent across the various neurologic disorders analyzed.

CONCLUSION

Childhood obesity buffered the association between neurologic disorders and postoperative pneumonia, consistent with an 'obesity paradox'. Further research exploring the underlying mechanisms for the obesity paradox in children with neurologic disorders is warranted.

Immune Cell Activation in Obesity and Cardiovascular Disease

PURPOSE OF REVIEW

In this review, we focus on immune cell activation in obesity and cardiovascular disease, highlighting specific immune cell microenvironments present in individuals with atherosclerosis, non-ischemic heart disease, hypertension, and infectious diseases.

RECENT FINDINGS

Obesity and cardiovascular disease are intimately linked and often characterized by inflammation and a cluster of metabolic complications. Compelling evidence from single-cell analysis suggests that obese adipose tissue is inflammatory and infiltrated by almost all immune cell populations. How this inflammatory tissue state contributes to more systemic conditions such as cardiovascular and infectious disease is less well understood. However, current research suggests that changes in the adipose tissue immune environment impact an individual's ability to combat illnesses such as influenza and SARS-CoV2. Obesity is becoming increasingly prevalent globally and is often associated with type 2 diabetes and heart disease. An increased inflammatory state is a major contributor to this association. Widespread chronic inflammation in these disease states is accompanied by an increase in both innate and adaptive immune cell activation. Acutely, these immune cell changes are beneficial as they sustain homeostasis as inflammation increases. However, persistent inflammation subsequently damages tissues and organs throughout the body. Future studies aimed at understanding the unique immune cell populations in each tissue compartment impacted by obesity may hold potential for therapeutic applications.

Are Undernutrition and Obesity Associated with Post-Discharge Mortality and Re-Hospitalization after Hospitalization with Community-Acquired Pneumonia?

Undernutrition is associated with increased mortality after hospitalization with community-acquired pneumonia (CAP), whereas obesity is associated with decreased mortality in most studies. We aimed to determine whether undernutrition and obesity are associated with increased risk of re-hospitalization and post-discharge mortality after hospitalization. This study was nested within the Surviving Pneumonia cohort, which is a prospective cohort of adults hospitalized with CAP. Patients were categorized as undernourished, well-nourished, overweight, or obese. Undernutrition was based on diagnostic criteria by the European Society for Clinical Nutrition and Metabolism. Risk of mortality was investigated using multivariate logistic regression and re-hospitalization with competing risk Cox regression where death was the competing event. Compared to well-nourished patients, undernourished patients had a higher risk of 90-day (OR 3.0, 95% CI 1.0; 21.4) mortality, but a similar 30-day and 180-day mortality risk. Obese patients had a similar re-hospitalization and mortality risk as well-nourished patients. In conclusion, among patients with CAP, undernutrition was associated with increased risk of mortality. Undernourished patients are high-risk patients, and our results indicate that in-hospital screening of undernutrition should be implemented to identify patients at mortality risk. Studies are required to investigate whether nutritional therapy after hospitalization with CAP would improve survival.

Obesity and the risk of catheter-related bloodstream infection: a systematic review and meta-analysis

Background

The role of obesity in catheter-related bloodstream infection has been reported in several studies, but it is still controversial. We conducted this meta-analysis to summarize existing evidence to assess the relationship between obesity and the risk of catheter-related bloodstream infection.

Methods

We searched MEDLINE, EMBASE, PubMed and Web of Science for the related studies published before January 2022. Meta-analysis was performed by use of a random-effects model.

Results

A total of 5 articles were included in this meta-analysis. Patients with body mass index  ≥ 25 kg/m² had an increased risk of catheter-related bloodstream infection (OR 1.75, 95% CI 1.38–2.22) in overall analysis. Further analysis indicated that patients with overweight, obesity and severely obesity were all significantly associated with a higher risk of for catheter-related bloodstream infection (OR 1.51 [1.10–2.08], OR 1.43 [1.12–1.82] and OR 2.74 [1.85–4.05], respectively).

Conclusion

This meta-analysis provided evidence that obesity was significantly associated with a higher risk of catheter-related bloodstream infection. Close attention should be paid to the complications and prognosis of obese patients with vascular catheterization in clinical work.

Association of Obesity With COVID-19 Severity and Mortality: An Updated Systemic Review, Meta-Analysis, and Meta-Regression

Background

Obesity affects the course of critical illnesses. We aimed to estimate the association of obesity with the severity and mortality in coronavirus disease 2019 (COVID-19) patients.

Data Sources

A systematic search was conducted from the inception of the COVID-19 pandemic through to 13 October 2021, on databases including Medline (PubMed), Embase, Science Web, and Cochrane Central Controlled Trials Registry. Preprint servers such as BioRxiv, MedRxiv, ChemRxiv, and SSRN were also scanned.

Study Selection and Data Extraction

Full-length articles focusing on the association of obesity and outcome in COVID-19 patients were included. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were used for study selection and data extraction. Our Population of interest were COVID-19 positive patients, obesity is our Intervention/Exposure point, Comparators are Non-obese vs obese patients The chief outcome of the study was the severity of the confirmed COVID-19 positive hospitalized patients in terms of admission to the intensive care unit (ICU) or the requirement of invasive mechanical ventilation/intubation with obesity. All-cause mortality in COVID-19 positive hospitalized patients with obesity was the secondary outcome of the study.

Results

In total, 3,140,413 patients from 167 studies were included in the study. Obesity was associated with an increased risk of severe disease (RR=1.52, 95% CI 1.41-1.63, p<0.001, I2 = 97%). Similarly, high mortality was observed in obese patients (RR=1.09, 95% CI 1.02-1.16, p=0.006, I2 = 97%). In multivariate meta-regression on severity, the covariate of the female gender, pulmonary disease, diabetes, older age, cardiovascular diseases, and hypertension was found to be significant and explained R2 = 40% of the between-study heterogeneity for severity. The aforementioned covariates were found to be significant for mortality as well, and these covariates collectively explained R2 = 50% of the between-study variability for mortality.

Conclusions

Our findings suggest that obesity is significantly associated with increased severity and higher mortality among COVID-19 patients. Therefore, the inclusion of obesity or its surrogate body mass index in prognostic scores and improvement of guidelines for patient care management is recommended.

No obesity paradox in patients with community-acquired pneumonia - secondary analysis of a randomized controlled trial

Background

Obesity is associated with an increased risk for several chronic conditions and mortality. However, there are data in support of beneficial outcome in acute medical conditions such as community-acquired pneumonia (CAP), termed “obesity paradox”. The aim of this study was to test the association of BMI with clinical outcomes in a large randomized clinical trial of patients hospitalized with CAP.

Design and Methods

In total, 773 patients hospitalized with CAP were included in this study. Patients were stratified into four groups according to their baseline BMI (underweight <18.5, normal weight 18.5–25, overweight 25–30, and obese >30 kg/m²). The primary endpoint was time to clinical stability (TTCS). Secondary endpoints included 30-day mortality, ICU admission rate, CAP complications, and duration of antibiotic treatment.

Results

BMI and TTCS had a U-shaped association with shortest TTCS among patients at an overweight BMI of 28 kg/m². In patients with obesity, there was a trend towards reduced hazards to reach clinical stability when compared to patients with normal weight (HR 0.82; 95%CI, 0.67–1.02; p = 0.07). In underweight BMI group TTCS was prolonged by 1 day (HR 0.63; 95%CI, 0.45–0.89; p = 0.008). There was no difference in mortality or ICU admission rates between BMI groups (p > 0.05). While in the underweight BMI group the total duration of antibiotic treatment was prolonged by 2.5 days (95%CI, 0.88–4.20, p = 0.003), there was no difference in patients with obesity.

Conclusions

The overweight BMI group had shortest time to clinical stability. While underweight patients face adverse clinical outcomes, there is neither beneficial, nor adverse outcome in patients with obesity hospitalized for CAP.

ClinicalTrials.gov (registration no. NCT00973154).

Bioimpedance Phase Angle as a Prognostic Tool in Late-Onset Pompe Disease: A Single-Centre Prospective Study With a 15-year Follow-Up

Background: Late-onset Pompe disease (LOPD) is an autosomal-recessive metabolic myopathy caused by deficiency of the lysosomal enzyme Acid Alpha—Glucosidase (GAA), leading to glycogen accumulation in proximal and axial muscles, and in the diaphragm. Enzyme Replacement Therapy (ERT) with recombinant GAA became available in 2006. Since then, several outcome measures have been investigated for the adequate follow-up of disease progression and treatment response, usually focusing on respiratory and motor function. Prognostic factors predicting outcome have not been identified till now.

Methods: In this single Centre, prospective study, we evaluate the response to enzyme replacement therapy in 15 patients (7 males) with LOPD in different stages of disease, aged 49.4 ± 16.1, followed-up for 15 years. Treatment response was measured by the 6-min walking test, vital capacity in supine and upright position, respiratory muscle strength, muscle MRI, manual muscle testing. We investigated the usefulness of Body Impedance Vectorial Analysis for serial body composition assessment.

Results: Although most patients with LOPD benefit from long-term treatment, some secondary decline may occur after the first 3–5 years. Some nutritional (lower body mass index, higher fat free mass, higher phase angle) and disease parameters (higher creatinine and shorter disease duration at the beginning of treatment) seem to predict a better motor outcome. Lower Phase Angle, possibly reflecting loss of integrity of skeletal muscle membranes and thus treatment mis-targeting, seems to correlate with worse treatment response on long-term follow-up.

Conclusion: Body Impedance Vectorial Analysis is a fast, easily performed and cheap tool that may be able to predict long-term treatment response in patients with LOPD. Low Phase angle may serve as a marker of muscle quality and may be used to predict the response to a muscle-targeted intervention such as ERT, thus improving the identification of patients needing a closer follow-up due to higher fragility and risk of deterioration.

Obesity is not associated with adverse outcomes among hospitalized patients with Clostridioides difficile infection

Background

Obesity is associated with increased risk for death in most infections but has not been studied as a risk factor for mortality in Clostridioides difficile infection (CDI). This study tested obesity as a risk factor for death in patients hospitalized with CDI. This was a three-center retrospective study that included hospitalized adults with CDI at Columbia University Irving Medical Center, Brigham and Women’s Hospital, and NYU Langone from 2010 to 2018. Multivariate logistic regression was used to assess the relationship between obesity, measured by body mass index, and death from any cause within 30 days after the index CDI test.

Results

Data for 3851 patients were analyzed, including 373 (9.7%) who died within 30 days following a diagnosis of CDI. After adjusting for other factors, BMI was not associated with increased risk for death in any BMI category [adjusted OR (aOR) 0.96, 95% CI 0.69 to 1.34 for BMI > 30 vs BMI 20–30; aOR 1.02, 95% CI 0.53 to 1.87 for BMI > 40 vs BMI 20–30]. After stratifying into three groups by age, there were trends towards increased mortality with obesity in the middle-aged (56–75 vs ≤ 55 years old) yet decreased mortality with obesity in the old (> 75 vs ≤ 55) (p = NS for all). Advanced age and low albumin were the factors most strongly associated with death.

Conclusions

We found no association between obesity and death among patients with CDI, in contrast to most other infections. Obesity is not likely to be useful for risk-stratifying hospitalized patients with CDI.

The causal relationship between obesity and skin and soft tissue infections: A two-sample Mendelian randomization study

OBJECTIVE

Many observational studies have shown that obesity strongly affects skin and soft tissue infections (SSTIs). However, whether a causal genetic relationship exists between obesity and SSTIs is unclear.

METHODS

A two-sample Mendelian randomization (MR) study was used to explore whether obesity is causally associated with SSTIs using a publicly released genome-wide association study (GWAS). An inverse-variance weighted (IVW) analysis was used as the primary analysis, and the results are reported as the odds ratios (ORs). Heterogeneity was tested using Cochran's Q test and the I² statistic, and horizontal pleiotropy was tested using the MR-Egger intercept and MR pleiotropy residual sum and outlier (MR-PRESSO).

RESULTS

The results of the MR analysis showed a positive effect of BMI on SSTIs (OR 1.544, 95% CI 1.399-1.704, P= 5.86 × 10^-18). After adjusting for the effect of type 2 diabetes (T2D) and peripheral vascular disease (PVD), the positive effect still existed. Then, we further assessed the effect of BMI on different types of SSTIs. The results showed that BMI caused an increased risk of impetigo, cutaneous abscess, furuncle and carbuncle, cellulitis, pilonidal cyst, and other local infections of skin and subcutaneous tissues, except for acute lymphadenitis. However, the associations disappeared after adjusting for the effect of T2D and PVD, and the associations between BMI and impetigo or cellulitis disappeared. Finally, we assessed the effects of several obesity-related characteristics on SSTIs. Waist circumference, hip circumference, body fat percentage, and whole-body fat mass, excluding waist-to-hip ratio, had a causal effect on an increased risk of SSTIs. However, the associations disappeared after adjusting for the effect of BMI.

CONCLUSION

This study found that obesity had a positive causal effect on SSTIs. Reasonable weight control is a possible way to reduce the occurrence of SSTIs, especially in patients undergoing surgery.

The effect of obesity on in-hospital mortality among patients with COVID-19 receiving corticosteroids

BACKGROUND AND AIMS

Obesity has been reported to be one of the most frequent comorbidities in COVID-19 patients and associated with higher rates of in-hospital mortality compared to non-obese patients. Acute kidney injury (AKI) is also known to be a complication associated with obesity in critically-ill COVID-19 patients. We aimed to investigate whether obesity was associated with increased risk of in-hospital mortality and AKI among patients with COVID-19 treated with corticosteroids.

METHODS

We utilized 9965 hospitalized COVID-19 patient data and divided patients who were treated with corticosteroids into 6 groups by body mass index (BMI) (less than 18.5, 18.5-25, 25-30, 30-35, 35-40, 40 kg/m² or greater). The association between BMI and in-hospital mortality and between BMI and incidence rate of AKI during admission among COVID-19 patients receiving corticosteroids were retrospectively investigated.

RESULTS

There were 4587 study participants receiving corticosteroids (mean age 66.5 ± 15.5 years, men 56.6%, mean BMI 29.0 ± 7.2 kg/m²). The smooth spline curve suggested a J-shape association between BMI and in-hospital mortality. Patients with BMI above 40 kg/m² exhibited a higher in-hospital mortality and higher incidence rate of AKI during admission compared to patients with BMI between 25 and 30 kg/m². The differences in in-hospital mortality and the rate of AKI were larger among patients with severe COVID-19.

CONCLUSIONS

Class III obesity was associated with high in-hospital mortality and AKI in patients with COVID-19 treated by corticosteroids. Clinicians must stay vigilant on the impact of class III obesity and development of AKI to disease trajectory of COVID-19 patients.

The effect of body mass index on the development of acute kidney injury and mortality in intensive care unit: is obesity paradox valid?

BACKGROUND

The conflicting results of studies on intensive care unit (ICU) mortality of obese patients and obese patients with acute kidney injury (AKI) reveal a paradox within a paradox. The aim of this study was to determine the effects of body mass index and obesity on AKI development and ICU mortality.

METHODS

The 4,459 patients treated between January 2015 and December 2019 in the ICU at a Tertiary Care Center in Turkey were analyzed retrospectively.

RESULTS

AKI developed more in obese patients with 69.8% (620). AKI development rates were similar in normal-weight (65.1%; 1172) and overweight patients (64.9%; 1149). The development of AKI in patients who presented with cerebrovascular diseases was higher in obese patients (81; 76.4%) than in normal-weight (158; 62.7%) and overweight (174; 60.8%) patients (p < 0.05). The risk of developing AKI was approximately 1.4 times (CI 95% = 1.177-1.662) higher in obese patients than in normal-weight patients. Dialysis was used more frequently in obese patients (24.3%, p < 0.001), who stayed longer in the ICU (p < 0.05). It was determined that the development of AKI in normal-weight and overweight patients increased mortality (p < 0.001) and that there was not a difference in mortality rates between obese patients with and without AKI.

CONCLUSION

The risk of AKI development was higher in obese patients but not in those who were in serious conditions. Another paradox was that the development of AKI was associated with a higher mortality rate in normal-weight and overweight patients, but not in obese patients. Cerebrovascular diseases as a cause of admission pose additional risks for AKI.

The effect of BMI on COVID-19 outcomes among older patients in South Korea: a nationwide retrospective cohort study

Background: The coronavirus disease 2019 (COVID-19) pandemic has caused deaths and shortages in medical resources worldwide, making the prediction of patient prognosis and the identification of risk factors very important. Increasing age is already known as one of the main risk factors for poor outcomes, but the effect of body mass index (BMI) on COVID-19 outcomes in older patients has not yet been investigated. Aim: We aimed to determine the effect of BMI on the severity and mortality of COVID-19 among older patients in South Korea. Methods: Data from 1272 COVID-19 patients (≥60 years old) were collected by the Korea Centers for Disease Control and Prevention. The odds ratios (ORs) of severe infection and death in the BMI groups were analyzed by logistic regression adjusted for covariates.Results: The underweight group (BMI<18.5 kg/m2) had a higher OR for death (adjusted OR = 2.23, 95% confidence interval [95% CI] = 1.06-4.52) than the normal weight group (BMI, 18.5-22.9 kg/m2). Overweight (BMI, 23.0-24.9 kg/m2) was associated with lower risks of both severe infection (adjusted OR = 0.55, 95% CI = 0.31-0.94) and death (adjusted OR = 0.50, 95% CI = 0.27-0.91). Conclusions: Underweight was associated with an increased risk of death, and overweight was related to lower risks of severe infection and death in older COVID-19 patients in Korea. However, this study was limited by the lack of availability of some information, including smoking status.KEY MESSAGESUnderweight is an independent risk factor of death in older COVID-19 patients.Overweight patients have a lower risk of death and severe infection than normal-weight patients.

Effect of Obesity on Clinical Outcomes of Patients Treated With Cefepime

Background: As the prevalence of obesity climbs, dosing of antimicrobials, particularly cephalosporins, is becoming a greater challenge for clinicians. Data are lacking for appropriate dosing of cefepime, an anti-pseudomonal cephalosporin that is widely used as an empiric anti-pseudomonal agent. Objective: The purpose of this study was to determine the rate of clinical treatment failure in obese patients compared with nonobese patients receiving cefepime as definitive monotherapy. Methods: Adult inpatients treated with cefepime monotherapy for ≥72 hours were included. Patients were excluded if they (1) were not able to achieve culture clearance within 72 hours and (2) had polymicrobial infections requiring more than one antibiotic for definitive therapy. Results: Fifty-eight obese patients and 56 nonobese patients were included. Pseudomonas aeruginosa, Escherichia coli, and Enterobacter spp were the most prevalent organisms isolated. Most organisms had a minimum inhibitory concentration of ≤1 µg/mL to cefepime with no differences in minimum inhibitory concentration distributions between groups. Definitively, 60% of patients received cefepime 1 g, while almost 40% received cefepime 2 g. Clinical failure occurred in 52% of patients (67% obese vs 36% nonobese; P = .001), with study group (odds ratio = 1.057, 95% confidence interval = 1.008-1.109) and respiratory source (odds ratio = 3.251, 95% confidence interval = 1.378-7.667) being independent predictors of failure. There were no differences in hospital length of stay, all-cause mortality, or 30-day readmissions. Conclusions: Obese patients treated with cefepime are more likely to experience treatment failure than nonobese patients. Larger trials examining the reasons for clinical failure in obese patients treated with cefepime are needed to confirm the findings from this preliminary work.

Impact of Underlying Comorbidities on Outcomes of Patients Treated with Ceftaroline Fosamil for Complicated Skin and Soft Tissue Infections: Pooled Results from Three Phase III Randomized Clinical Trials

Introduction

In three phase III randomized controlled trials, ceftaroline fosamil was shown to be non-inferior to vancomycin plus aztreonam for the treatment of complicated skin and soft tissue infections (cSSTIs). This exploratory analysis evaluated the impact of underlying comorbidities on clinical outcomes in patients with cSSTI pooled from these three studies.

Methods

CANVAS 1 and 2 and COVERS evaluated ceftaroline fosamil (600 mg every 12 h [q12h]; 600 mg every 8 h [q8h; COVERS]) versus vancomycin plus aztreonam (1 g q12h each [CANVAS 1 and 2]; vancomycin 15 mg/kg q12h and aztreonam 1 g q8h [COVERS]) in hospitalized adults with cSSTI. The primary efficacy variable in each trial was clinical response at the test-of-cure (TOC) visit. Subgroup analyses were performed on the pooled clinically evaluable (CE) population, exploring the impact of age and various baseline comorbidities.

Results

Overall, 1808 patients were included in the CE population (1005 ceftaroline fosamil; 803 vancomycin plus aztreonam). Clinical cure rates at TOC were 89.7% (ceftaroline fosamil) and 90.8% (vancomycin plus aztreonam) (difference [95% confidence interval] − 1.13 [− 3.87, 1.67]). Clinical response rates were similar between treatment groups, regardless of age (≤ 65 years or > 65 years), and in subgroups of patients with and without diabetes mellitus, peripheral vascular disease, cancer/malignancy, renal impairment, and obesity; within these subgroups, efficacy and safety results were generally consistent with those of the overall cSSTI population.

Conclusions

This analysis provides supportive evidence of the efficacy of ceftaroline fosamil in patients with cSSTI and underlying comorbidities.

Trial Registration

CANVAS 1, NCT00424190 and CANVAS 2, NCT00423657 (both trials first posted on ClinicalTrials.gov 18/01/2007); COVERS, NCT01499277 (first posted on ClinicalTrials.gov 26/12/2011).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00557-w.

The Impact of Obesity on Critical Illnesses

ABSTRACT

In the last few decades, obesity became one of the world's greatest health challenges reaching a size of global epidemic in virtually all socioeconomic statuses and all age groups. Obesity is a risk factor for many health problems and as its prevalence gradually increases is becoming a significant economic and health burden. In this manuscript we describe how normal respiratory and cardiovascular physiology is altered by obesity. We review past and current literature to describe how obesity affects outcomes of patients facing critical illnesses and discuss some controversies related to this topic.

Impact of a hospital-wide computerised approach to optimise the quality of antimicrobial prescriptions in patients with severe obesity: a quasi-experimental study

Background

Rates of adherence to available recommendations for dose adjustments in patients with severe obesity are generally low. Hence, antimicrobials are often underdosed in these patients. Antimicrobial stewardship programmes can improve the use of antimicrobials in hospitalised patients. The aim of the study was to analyse the impact of an antimicrobial stewardship programme based on a computerised clinical decision support system for optimal dosing and antimicrobial use in inpatients with severe obesity.

Methods

This quasi-experimental retrospective study using interrupted time series was conducted in an academic centre in Canada from August 2008 to June 2018. The Antimicrobial Prescription Surveillance System was implemented in August 2010 (intervention 1) and specific rules targeting patients with class III obesity (body mass index ≥ 40 kg/m²) were added in June 2014 (intervention 2). Data were collected from all hospitalised adults receiving antimicrobials which required dose adjustment for severe obesity and were stratified by body mass index. Segmented regression analysis of interrupted time series was used to evaluate the impact of the Antimicrobial Prescription Surveillance System on the proportion of inappropriate days of therapy according to posology and on antimicrobial consumption.

Results

Overall, 65 205 antimicrobial prescriptions (68% non-obese, 25% class I-II obesity, and 7% class III obesity) were analysed. In patients with class III obesity, the intervention was associated with a decrease in the proportion of inappropriate days of therapy (trend after the first intervention, −0.8% per 2-month period [95% CI −1.1 to −0.5], p < 0.001; intercept, 11.3% [95% CI 8.2 to 14.5], p < 0.001), which led to a reduction of 35% over an eight-year period (from pre-intervention level of 19.1%). Intervention 1 resulted in a downward trend in antimicrobial consumption, followed by an increasing trend after intervention 2. In these patients, the most frequent interventions made by pharmacists targeted posology (46%).

Conclusions

Antimicrobial Prescription Surveillance System had a positive impact on dosing optimisation and antimicrobial consumption in patients with class III obesity. Improving antimicrobial prescriptions in these patients is important because suboptimal dosing could be associated with unfavourable outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06682-8.

The impact of obesity on seasonal influenza: a single-center, retrospective study conducted in Israel

Obesity is associated with an increased susceptibility to infections. Several studies have reported adverse clinical outcomes of influenza among obese individuals. Our aim was to examine the association between obesity and the clinical outcomes of hospitalized adult patients ill with seasonal influenza. Consecutive hospitalized adult patients between 10/2017 and 4/2018 with laboratory confirmed influenza A and B were divided into an obese group (body mass index (BMI) ≥ 30 kg/m2) and controls. The primary outcome was a composite endpoint of 30-day all-cause mortality, vasopressor use, mechanical ventilation, ICU admission, and severe influenza complication (myocarditis and encephalitis). Secondary outcomes encompassed all the components of the primary outcome, 90-day all-cause mortality, occurrence of pneumonia, length of hospital stay, and 90-day readmission rates. The study comprised 512 hospitalized adults diagnosed with laboratory-confirmed influenza A (195/512) and B (317/512). Within this group, 17% (86/512) were classified obese; the remaining 83% (426/512) were controls. Results of the composite outcome (7/85, 8% vs. 45/422, 11%; p=0.5) and the crude 30-day all-cause mortality rate (5/86, 6% vs. 34/426, 8%, p=0.5) were similar between the two groups. The multivariate analysis demonstrated that obesity was not a significant risk factor for influenza adverse events (OR=1.3, CI 95% 0.3-3.3; p=0.5), whereas advanced age, chronic kidney disease, and hypoalbuminemia were significant risk factors (OR=1.03, OR=2.7, and OR=5.4, respectively). Obesity was not associated with influenza-related morbidity and mortality among the hospitalized adults during the 2017-2018 influenza season. Further studies researching different influenza seasons are essential.

Relationship Between Multidrug-Resistant Enterobacterales and Obesity in Older Adults

Purpose

The objective of our study was to determine if obesity is associated with the presence of multidrug-resistant (MDR) bacteria among Enterobacterales.

Patients and Methods

This two-center cohort study included adult hospitalized patients with at least one specimen sampled from any site for bacterial culture yielding an Enterobacterales bacterial species from November 2016 to May 2017. Study groups were stratified by obesity status based on body mass index <30 kg/m² (non-obese) and ≥30 kg/m² (obese). The primary outcome was the presence of gram-negative MDR bacteria defined as presumptive extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales (ceftriaxone resistance) or carbapenem-resistant Enterobacterales (CRE). A multivariable logistic regression model was fit to estimate the adjusted odds ratio while controlling for potential confounders.

Results

A total of 366 patients, 238 non-obese and 128 obese, were included. The most common gram-negative bacterial species identified was Escherichia coli (64.2%). There was a higher proportion of gram-negative MDR bacteria in obese versus non-obese patients (18.8 versus 11.3%, P=0.057). Obesity was independently associated with gram-negative MDR bacteria after controlling for confounders (adjusted odds ratio, 1.92; 95% CI 1.03–3.60). The association did not significantly vary by diabetes status (interaction term P=0.792).

Conclusion

Among older adult hospitalized patients, obesity was independently associated with the presence of a gram-negative MDR bacteria (presumptive ESBL or CRE) in a culture.

Path Analysis of the Impact of Obesity on Postoperative Outcomes in Colorectal Cancer Patients: A Population-Based Study

Background: Obesity is adversely affecting perioperative outcomes; however, long-term outcomes do not appear to be affected by excess body weight (the obesity paradox). The purpose of this study is to examine the association between obesity and surgical outcomes in patients with colorectal cancer (CRC) using data from the United States National Inpatient Sample (NIS). Methods: Patients ≥20 years old diagnosed with CRC who received surgery were identified in the 2004–2014 NIS database. Patients who were obese (ICD-9-CM code: 278.0) were matched with controls (non-obese) in a 1:4 ratio for age, sex, and severity of CRC (metastasis vs. no metastasis). Linear regression and path analysis were used to compare outcomes between obese and non-obese patients. A total of 107,067 patients (53,376 males, 53,691 females) were included in the analysis, and 7.86% were obese. Results: The rates of postoperative infection, shock, bleeding, wound disruption, and digestive system complications were significantly different between the obese and non-obese groups. The obesity group had increased incidence of postoperative infection by 1.9% (∂P/∂X = 0.019), shock by 0.25% (∂P/∂X = 0.0025), postoperative bleeding by 0.5% (∂P/∂X = 0.005), wound disruption by 0.6% (∂P/∂X = 0.006), and digestive system complications by 1.35% (∂P/∂X = 0.0135). Path analysis showed that obesity group had higher in-hospital mortality through mentioned above five complications by 66.65 × 10⁻⁵%, length of hospital stay by 0.32 days, and total hospital charges by 2384 US dollars. Conclusions: Obesity increases the risk of postoperative complications in patients with CRC undergoing surgery. It also increased in-hospital mortality, length of hospital stay, and total hospital charges. Therefore, patients with obesity might require a higher level of preoperative interventions and complications monitoring to improve outcomes.

Susceptibility and Severity of Viral Infections in Obesity: Lessons from Influenza to COVID-19. Does Leptin Play a Role?

The recent pandemic Sars-CoV2 infection and studies on previous influenza epidemic have drawn attention to the association between the obesity and infectious diseases susceptibility and worse outcome. Metabolic complications, nutritional aspects, physical inactivity, and a chronic unbalance in the hormonal and adipocytokine microenvironment are major determinants in the severity of viral infections in obesity. By these pleiotropic mechanisms obesity impairs immune surveillance and the higher leptin concentrations produced by adipose tissue and that characterize obesity substantially contribute to such immune response dysregulation. Indeed, leptin not only controls energy balance and body weight, but also plays a regulatory role in the interplay between energy metabolism and immune system. Since leptin receptor is expressed throughout the immune system, leptin may exert effects on cells of both innate and adaptive immune system. Chronic inflammatory states due to metabolic (i.e., obesity) as well as infectious diseases increase leptin concentrations and consequently lead to leptin resistance further fueling inflammation. Multiple factors, including inflammation and ER stress, contribute to leptin resistance. Thus, if leptin is recognized as one of the adipokines responsible for the low grade inflammation found in obesity, on the other hand, impairments of leptin signaling due to leptin resistance appear to blunt the immunologic effects of leptin and possibly contribute to impaired vaccine-induced immune responses. However, many aspects concerning leptin interactions with inflammation and immune system as well as the therapeutical approaches to overcome leptin resistance and reduced vaccine effectiveness in obesity remain a challenge for future research.

Obesity and Mortality Among Patients Diagnosed With COVID-19: A Systematic Review and Meta-Analysis

Coronavirus disease 2019 (COVID-19) has already raised serious concern globally as the number of confirmed or suspected cases have increased rapidly. Epidemiological studies reported that obesity is associated with a higher rate of mortality in patients with COVID-19. Yet, to our knowledge, there is no comprehensive systematic review and meta-analysis to assess the effects of obesity and mortality among patients with COVID-19. We, therefore, aimed to evaluate the effect of obesity, associated comorbidities, and other factors on the risk of death due to COVID-19. We did a systematic search on PubMed, EMBASE, Google Scholar, Web of Science, and Scopus between January 1, 2020, and August 30, 2020. We followed Cochrane Guidelines to find relevant articles, and two reviewers extracted data from retrieved articles. Disagreement during those stages was resolved by discussion with the main investigator. The random-effects model was used to calculate effect sizes. We included 17 articles with a total of 543,399 patients. Obesity was significantly associated with an increased risk of mortality among patients with COVID-19 (RRadjust: 1.42 (95%CI: 1.24-1.63, p < 0.001). The pooled risk ratio for class I, class II, and class III obesity were 1.27 (95%CI: 1.05-1.54, p = 0.01), 1.56 (95%CI: 1.11-2.19, p < 0.01), and 1.92 (95%CI: 1.50-2.47, p < 0.001), respectively). In subgroup analysis, the pooled risk ratio for the patients with stroke, CPOD, CKD, and diabetes were 1.80 (95%CI: 0.89-3.64, p = 0.10), 1.57 (95%CI: 1.57-1.91, p < 0.001), 1.34 (95%CI: 1.18-1.52, p < 0.001), and 1.19 (1.07-1.32, p = 0.001), respectively. However, patients with obesity who were more than 65 years had a higher risk of mortality (RR: 2.54; 95%CI: 1.62-3.67, p < 0.001). Our study showed that obesity was associated with an increased risk of death from COVID-19, particularly in patients aged more than 65 years. Physicians should aware of these risk factors when dealing with patients with COVID-19 and take early treatment intervention to reduce the mortality of COVID-19 patients.

Skin and obesity in childhood: an update

<abstract> <p>Overweight and obesity have grown in children in the last decades and are now an epidemic, leading to significant public health issues in developed and underdeveloped nations. Obese children have a higher prevalence of skin lesions than normal weight children. The present study is an updated-on state of the art of studies describing the association between childhood obesity and related skin lesions. The most frequent obesity-associated dermatological complications in children are acanthosis nigricans and acrochordons, atopic dermatitis, skin infections, and endocrinological changes including hyperinsulinism and hyperandrogenism. Other common skin manifestations associated with obesity are striae distensae and plantar hyperkeratosis. Although the causes of the majority of the skin lesions associated with obesity are not known, the larger mass of adipose tissue and the secretion of peptides (cytokines, hormones, etc.) from enlarged fat cells due to obesity could lead to skin lesions. Therefore, the prevention of obesity is essential to avoid most skin-associated lesions.</p> </abstract>

Obesity is a potential risk factor contributing to clinical manifestations of COVID-19

BACKGROUND

Since December 2019, novel coronavirus (SARS-CoV-2)-induced pneumonia (COVID-19) occurred in Wuhan, and rapidly spread throughout China. COVID-19 patients demonstrated significantly different outcomes in clinic. We aimed to figure out whether obesity is a risk factor influencing the progression and prognosis of COVID-19.

METHODS

95 patients with COVID-19 were divided into obesity group and non-obesity group according to their body mass index (BMI). The demographic data, clinical characteristics, laboratory examination, and chest computed tomography (CT) were collected, analyzed and compared between two groups.

RESULTS

Our data showed that COVID-19 patients with obesity had more underlying diseases and higher mortality rate compared to those without obesity. Furthermore, patients with obesity also demonstrated more severe pathological change in lung and higher blood lymphocytes, triglycerides, IL-6, CRP, cystatin C, alanine aminotransferase (ALT), erythrocyte sedimentation rate (ESR), which may greatly influence disease progression and poor prognosis of COVID-19.

CONCLUSIONS

It suggest that obesity contributes to clinical manifestations and may influence the progression and prognosis of COVID-19 and it is considered as a potential risk factor of the prognosis of COVID-19. Special medical care and appropriate intervention should be performed in obesity patients with COVID-19 during hospitalization and later clinical follow-up, especially for those with additional other comorbidities.

Clinical, Imaging and Procedural Risk Factors for Intrauterine Infective Complications After Uterine Fibroid Embolisation: A Retrospective Case Control Study

Introduction

This was a retrospective case–control study at a single tertiary centre investigating all UFE procedures between January 2013 and December 2018 for symptomatic fibroids. The aim was to determine the clinical, imaging and procedural risk factors which impact upon the risk of post-uterine fibroid embolisation (UFE) intrauterine infection. Cases were patients which developed intrauterine infection post-procedure, and controls were the background UFE population without infection.

Methods

Clinical demographics, presenting symptoms, uterine and fibroid characteristics on imaging and procedural variants were analysed. A p value of less than 0.05 was considered statistically significant. The main outcome measures were presence of infection and requirement of emergency hysterectomy.

Results

333 technically successful UFE procedures were performed in 330 patients. Infection occurred after 25 procedures (7.5%). 3 of these patients progressed to overwhelming sepsis and required emergency hysterectomy. Clinical obesity (BMI > 30) (OR 1.53 [1.18–1.99]) and uterine volume > 1000cm3 (2.94 [1.15–7.54]) were found to increase the risk of infection

Conclusions

UFE is generally safe in patients with symptomatic fibroids. Obese patients (BMI > 30) and those with large volume uteri (> 1000cm³) are at slight increased risk of developing infection and require appropriate pre-procedural counselling, as well as careful post-UFE follow-up. BMI and uterine volume may be useful to assess before the procedure to help to determine post-UFE infection risk.

Electronic supplementary material

The online version of this article (10.1007/s00270-020-02622-2) contains supplementary material, which is available to authorised users.

Impact of Obesity on Ceftriaxone Efficacy

Background: Ceftriaxone has standard, set dosing regimens that may not achieve adequate serum concentrations in obese patients compared to non-obese patients. The purpose of this study was to evaluate the effect of obesity on ceftriaxone efficacy when used as definitive monotherapy to treat infections. Methods: This retrospective cohort included adult inpatients treated with ceftriaxone monotherapy for ≥72 h between July 01, 2015-July 31, 2017. Patients were excluded if their infection lacked source control within 72 h or if they had polymicrobial infections requiring more than one antibiotic for definitive therapy. The primary outcome was the rate of clinical failure between obese versus non-obese patients, defined as a composite of (1) change in definitive therapy > 72 h due to clinical worsening; (2) residual leukocytosis (white blood cell count (WBC) > 10 × 10⁹/L) > 72 h after treatment initiation; (3) presence of a fever (single temperature > 100.9 °F) > 72 h after treatment initiation; or (4) readmission within 30 days due to re-infection with the same organism. Results: A total of 101 patients were included in the study: 39 obese and 62 non-obese. The most common indications for ceftriaxone were urinary tract (52.5%), respiratory tract (24.8%), and bloodstream (24.8%) infections. The most commonly isolated organisms were Escherichia coli (48.5%) and Klebsiella species (15.8%). Most patients received 1g every 24 h. Clinical failure was observed in 61.5% of obese patients versus 40.3% of non-obese patients (p = 0.038). Conclusion: Obese patients treated with ceftriaxone were more likely to experience clinical failure when compared to non-obese patients. Further analyses are warranted to determine if weight-based dosing is required in obese patients treated with ceftriaxone.

Disease characteristics of MCT8 deficiency: an international, retrospective, multicentre cohort study

BACKGROUND

Disordered thyroid hormone transport, due to mutations in the SLC16A2 gene encoding monocarboxylate transporter 8 (MCT8), is characterised by intellectual and motor disability resulting from cerebral hypothyroidism and chronic peripheral thyrotoxicosis. We sought to systematically assess the phenotypic characteristics and natural history of patients with MCT8 deficiency.

METHODS

We did an international, multicentre, cohort study, analysing retrospective data from Jan 1, 2003, to Dec 31, 2019, from patients with MCT8 deficiency followed up in 47 hospitals in 22 countries globally. The key inclusion criterion was genetically confirmed MCT8 deficiency. There were no exclusion criteria. Our primary objective was to analyse the overall survival of patients with MCT8 deficiency and document causes of death. We also compared survival between patients who did or did not attain full head control by age 1·5 years and between patients who were or were not underweight by age 1-3 years (defined as a bodyweight-for-age Z score <-2 SDs or <5th percentile according to WHO definition). Other objectives were to assess neurocognitive function and outcomes, and clinical parameters including anthropometric characteristics, biochemical markers, and neuroimaging findings.

FINDINGS

Between Oct 14, 2014, and Jan 17, 2020, we enrolled 151 patients with 73 different MCT8 (SLC16A2) mutations. Median age at diagnosis was 24·0 months (IQR 12·0-60·0, range 0·0-744·0). 32 (21%) of 151 patients died; the main causes of mortality in these patients were pulmonary infection (six [19%]) and sudden death (six [19%]). Median overall survival was 35·0 years (95% CI 8·3-61·7). Individuals who did not attain head control by age 1·5 years had an increased risk of death compared with patients who did attain head control (hazard ratio [HR] 3·46, 95% CI 1·76-8·34; log-rank test p=0·0041). Patients who were underweight during age 1-3 years had an increased risk for death compared with patients who were of normal bodyweight at this age (HR 4·71, 95% CI 1·26-17·58, p=0·021). The few motor and cognitive abilities of patients did not improve with age, as evidenced by the absence of significant correlations between biological age and scores on the Gross Motor Function Measure-88 and Bayley Scales of Infant Development III. Tri-iodothyronine concentrations were above the age-specific upper limit in 96 (95%) of 101 patients and free thyroxine concentrations were below the age-specific lower limit in 94 (89%) of 106 patients. 59 (71%) of 83 patients were underweight. 25 (53%) of 47 patients had elevated systolic blood pressure above the 90th percentile, 34 (76%) of 45 patients had premature atrial contractions, and 20 (31%) of 64 had resting tachycardia. The most consistent MRI finding was a global delay in myelination, which occurred in 13 (100%) of 13 patients.

INTERPRETATION

Our description of characteristics of MCT8 deficiency in a large patient cohort reveals poor survival with a high prevalence of treatable underlying risk factors, and provides knowledge that might inform clinical management and future evaluation of therapies.

FUNDING

Netherlands Organisation for Health Research and Development, and the Sherman Foundation.

The Implication of Oxidative Stress and AMPK-Nrf2 Antioxidative Signaling in Pneumonia Pathogenesis

It is widely recognized that chemical, physical, and biological factors can singly or synergistically evoke the excessive production of oxidative stress in pulmonary tissue that followed by pulmonary lesions and pneumonia. In addition, metabolic and endocrine disorder-induced diseases such as diabetes and obesity often expressed higher susceptibility to pulmonary infections, and presented severe symptoms which increasing the mortality rate. Therefore, the connection between the lesion of the lungs and the metabolic/endocrine disorders is an interesting and essential issue to be addressed. Studies have noticed a similar pathological feature in both infectious pneumonia and metabolic disease-intercurrent pulmonary lesions, that is, from the view of molecular pathology, the accumulation of excessive reactive oxygen species (ROS) in pulmonary tissue accompanying with activated pro-inflammatory signals. Meanwhile, Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and nuclear factor erythroid-2-related factor 2 (Nrf2) signaling plays important role in metabolic/endocrine homeostasis and infection response, and it's closely associated with the anti-oxidative capacity of the body. For this reason, this review will start from the summary upon the implication of ROS accumulation, and to discuss how AMPK-Nrf2 signaling contributes to maintaining the metabolic/endocrine homeostasis and attenuates the susceptibility of pulmonary infections.

Obesity Is Associated with Decreased Risk of Clostridium difficile Infection in Hospitalized Patients with Pouchitis

BACKGROUND

Clostridium difficile infection (CDI) is one of the leading causes of health-care-associated infections in the USA. There are limited data available regarding CDI in hospitalized patients with inflammatory bowel disease-related ileal pouch.

AIMS

This study aimed to evaluate the demographics, clinical features, risk factors, and admission outcomes among hospitalized patients with CDI-related pouchitis (CDP).

METHODS

Retrospective chart review was performed for patients who were admitted to our institute for pouchitis between 2013 and 2016 to identify patients with CDP. Logistic regression analysis was performed to assess the risk factors associated with CDP.

RESULTS

A total of 160 subjects with pouchitis had a total of 218 admissions during the study period. Primary admission diagnosis was pouchitis or inflammatory bowel disease flare-up for 202 (93%) admissions. Clostridium difficile was tested at least once for 72 patients, and the diagnosis of CDP was established for 16 (10%) patients. All patients with CDP were symptomatic, 13 (81%) had diarrhea, 8 (50%) had abdominal pain, 7 (44%) had nausea/vomiting, and 2 (13%) had gastrointestinal bleeding. On multivariable analysis, only body mass index > 25 (OR 0.25, 95% CI 0.06-0.94, p = 0.048) was significantly associated with decreased risk of CDP. No patients in CDP cohort were admitted to ICU, died at the hospital, or readmitted in 30 days after the discharge.

CONCLUSIONS

In our cohort, obesity was associated with low risk of CDP among hospitalized patients with pouchitis. This finding warrants further validation in prospective studies.

From Influenza Virus to Novel Corona Virus (SARS-CoV-2)-The Contribution of Obesity

From the beginning of 2020, the governments and the health systems around the world are tackling infections and fatalities caused by the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2) resulting in the coronavirus disease 2019 (COVID-19). This virus pandemic has turned more complicated as individuals with co-morbidities like diabetes, cardiovascular conditions and obesity are at a high risk of acquiring infection and suffering from a more severe course of disease. Prolonged viral infection and obesity are independently known to lower the immune response and a combination can thus result in a "cytokine storm" and a substantial weakening of the immune system. With the rise in obesity cases globally, the chances that obese individuals will acquire infection and need hospitalization are heightened. In this review, we discuss why obesity, a low-grade chronic inflammation, contributes toward the increased severity in COVID-19 patients. We suggest that increased inflammation, activation of renin-angiotensin-aldosterone system, elevated adipokines and higher ectopic fat may be the factors contributing to the disease severity, in particular deteriorating the cardiovascular and lung function, in obese individuals. We look at the many lessons learnt from the 2009 H1N1 influenza A pandemic and relate it to the very little but fast incoming information that is available from the SARS-CoV-2 infected individuals with overweight and obesity.

Macronutrients modulate survival to infection and immunity in Drosophila

Immunity and nutrition are two essential modulators of individual fitness. However, while the implications of immune function and nutrition on an individual's lifespan and reproduction are well established, the interplay between feeding behaviour, infection and immune function remains poorly understood. Asking how ecological and physiological factors affect immune responses and resistance to infections is a central theme of eco‐immunology.

In this study, we used the fruit fly, Drosophila melanogaster, to investigate how infection through septic injury modulates nutritional intake and how macronutrient balance affects survival to infection by the pathogenic Gram‐positive bacterium Micrococcus luteus.

Our results show that infected flies maintain carbohydrate intake, but reduce protein intake, thereby shifting from a protein‐to‐carbohydrate (P:C) ratio of ~1:4 to ~1:10 relative to non‐infected and sham‐infected flies. Strikingly, the proportion of flies dying after M. luteus infection was significantly lower when flies were fed a low‐P high‐C diet, revealing that flies shift their macronutrient intake as means of nutritional self‐medication against bacterial infection.

These results are likely due to the effects of the macronutrient balance on the regulation of the constitutive expression of innate immune genes, as a low‐P high‐C diet was linked to an upregulation in the expression of key antimicrobial peptides.

Together, our results reveal the intricate relationship between macronutrient intake and resistance to infection and integrate the molecular cross‐talk between metabolic and immune pathways into the framework of nutritional immunology.

Association Between Estimated Pharmacokinetic/Pharmacodynamic Predictions of Efficacy and Observed Clinical Outcomes in Obese and Nonobese Patients With Enterobacteriaceae Bloodstream Infections

Background

Evidence on pharmacokinetic/pharmacodynamic (PK/PD) alterations and clinical outcomes in obese patients with serious infections remains limited. This study aimed to evaluate predicted PK/PD indices of efficacy and observed clinical outcomes between obese and nonobese patients receiving cefepime or piperacillin-tazobactam for Enterobacteriaceae bacteremia.

Methods

This was a retrospective study of adult inpatients from 1/2012 to 9/2015 with Enterobacteriaceae bacteremia who received empiric cefepime or piperacillin-tazobactam. The primary outcome was clinical cure. First-dose free-drug exposure was estimated via predicted concentrations generated from population PK analyses and used to assess PD target attainment (>50% fT > minimum inhibitory concentration [MIC]) for the specific Enterobacteriaceae isolate. Multivariable logistic regression was utilized to identify independent predictors of clinical cure.

Results

One hundred forty-two patients were included, 57 obese and 85 nonobese. Clinical cure was achieved in 68.4% of obese and 62.4% of nonobese patients (P = .458). No significant difference in outcomes was observed when evaluated by World Health Organization (WHO) obesity classes. The PK/PD target was achieved in 98.2% of obese and 91.8% of nonobese patients (P = .144). Independent predictors of clinical cure were immunosuppression and a shorter duration of bacteremia. Obesity was not identified as a significant predictor of clinical outcomes.

Conclusions

Neither predicted PK/PD parameters nor clinical outcomes differed significantly between obese and nonobese patients treated with piperacillin-tazobactam or cefepime. As the majority of patients received extended-infusion piperacillin-tazobactam for bacteremia due to pathogens with low MICs, the potentially detrimental pathophysiologic derangements caused by obesity may not have been realized. Further studies are warranted to establish the optimal treatment of serious infections in obese patients.

Effectiveness and safety of the tri-iodothyronine analogue Triac in children and adults with MCT8 deficiency: an international, single-arm, open-label, phase 2 trial

BACKGROUND

Deficiency of the thyroid hormone transporter monocarboxylate transporter 8 (MCT8) causes severe intellectual and motor disability and high serum tri-iodothyronine (T₃) concentrations (Allan-Herndon-Dudley syndrome). This chronic thyrotoxicosis leads to progressive deterioration in bodyweight, tachycardia, and muscle wasting, predisposing affected individuals to substantial morbidity and mortality. Treatment that safely alleviates peripheral thyrotoxicosis and reverses cerebral hypothyroidism is not yet available. We aimed to investigate the effects of treatment with the T₃ analogue Triac (3,3',5-tri-iodothyroacetic acid, or tiratricol), in patients with MCT8 deficiency.

METHODS

In this investigator-initiated, multicentre, open-label, single-arm, phase 2, pragmatic trial, we investigated the effectiveness and safety of oral Triac in male paediatric and adult patients with MCT8 deficiency in eight countries in Europe and one site in South Africa. Triac was administered in a predefined escalating dose schedule-after the initial dose of once-daily 350 μg Triac, the daily dose was increased progressively in 350 μg increments, with the goal of attaining serum total T₃ concentrations within the target range of 1·4-2·5 nmol/L. We assessed changes in several clinical and biochemical signs of hyperthyroidism between baseline and 12 months of treatment. The prespecified primary endpoint was the change in serum T₃ concentrations from baseline to month 12. The co-primary endpoints were changes in concentrations of serum thyroid-stimulating hormone (TSH), free and total thyroxine (T₄), and total reverse T₃ from baseline to month 12. These analyses were done in patients who received at least one dose of Triac and had at least one post-baseline evaluation of serum throid function. This trial is registered with ClinicalTrials.gov, number NCT02060474.

FINDINGS

Between Oct 15, 2014, and June 1, 2017, we screened 50 patients, all of whom were eligible. Of these patients, four (8%) patients decided not to participate because of travel commitments. 46 (92%) patients were therefore enrolled in the trial to receive Triac (median age 7·1 years [range 0·8-66·8]). 45 (98%) participants received Triac and had at least one follow-up measurement of thyroid function and thus were included in the analyses of the primary endpoints. Of these 45 patients, five did not complete the trial (two patients withdrew [travel burden, severe pre-existing comorbidity], one was lost to follow-up, one developed of Graves disease, and one died of sepsis). Patients required a mean dose of 38.3 μg/kg of bodyweight (range 6·4-84·3) to attain T₃ concentrations within the target range. Serum T₃ concentration decreased from 4·97 nmol/L (SD 1·55) at baseline to 1·82 nmol/L (0·69) at month 12 (mean decrease 3·15 nmol/L, 95% CI 2·68-3·62; p<0·0001), while serum TSH concentrations decreased from 2·91 mU/L (SD 1·68) to 1·02 mU/L (1·14; mean decrease 1·89 mU/L, 1·39-2·39; p<0·0001) and serum free T₄ concentrations decreased from 9·5 pmol/L (SD 2·5) to 3·4 (1·6; mean decrease 6·1 pmol/L (5·4-6·8; p<0·0001). Additionally, serum total T₄ concentrations decreased by 31·6 nmol/L (28·0-35·2; p<0·0001) and reverse T₃ by 0·08 nmol/L (0·05-0·10; p<0·0001). Seven treatment-related adverse events (transiently increased perspiration or irritability) occurred in six (13%) patients. 26 serious adverse events that were considered unrelated to treatment occurred in 18 (39%) patients (mostly hospital admissions because of infections). One patient died from pulmonary sepsis leading to multi-organ failure, which was unrelated to Triac treatment.

INTERPRETATION

Key features of peripheral thyrotoxicosis were alleviated in paediatric and adult patients with MCT8 deficiency who were treated with Triac. Triac seems a reasonable treatment strategy to ameliorate the consequences of untreated peripheral thyrotoxicosis in patients with MCT8 deficiency.

FUNDING

Dutch Scientific Organization, Sherman Foundation, NeMO Foundation, Wellcome Trust, UK National Institute for Health Research Cambridge Biomedical Centre, Toulouse University Hospital, and Una Vita Rara ONLUS.

Serum albumin saturation test based on non-esterified fatty acids imbalance for clinical employment

Fatty acids are fundamental as energy and structural source to the human cells. They are not usually found free in human circulation. Alteration in fatty acids metabolism is linked to diseases such as diabetes, preeclampsia, heart disease, and some infectious diseases. Increased levels of non-esterified fatty acids (NEFA) may cause cell dysfunction and lipotoxicity. Since physiologically fatty acids are transported bound to albumin, we propose here a simple and cheap test that consists of albumin isoelectric focusing determination to measure the potential systemic NEFA cytotoxicity. For validation of this method, albumin isoelectric focusing in 51 serum samples from 40 critically ill patients and 11 controls was compared with NEFA/albumin ratios measured by HPLC. We called this approach an albumin saturation test. This test may indicate to physicians the potential NEFA lipotoxicity guiding them throughout better patient management. The albumin saturation test can point out serum albumin-NEFA saturation through a cheap assay that could be performed by any care facility.

Immune-endocrine interactions related to a high risk of infections in chronic metabolic diseases: The role of PPAR gamma

Diverse disturbances in immune-endocrine circuitries are involved in the development and aggravation of several chronic metabolic diseases (CMDs), including obesity, diabetes, and metabolic syndrome. The chronic inflammatory syndrome observed in CMDs culminates in dysregulated immune responses with low microbial killing efficiency, by means low host innate immune response, and loss of ability to eliminate the pathogens, which results in a high prevalence of infectious diseases, including pneumonia, tuberculosis, and sepsis. Herein, we review evidence pointing out PPARγ as a putative player in immune-endocrine disturbances related to increased risk of infections in CMDs. Cumulated evidence indicates that PPARγ activation modulates host cells to control inflammation during CMDs because of PPARγ agonists have anti-inflammatory and pro-resolutive properties, increasing host ability to eliminate pathogen, modulating hormone production, and restoring glucose and lipid homeostasis. As such, we propose PPARγ as a putative therapeutic adjuvant for patients with CMDs to favor a better infection control.

Diagnostic Stewardship: A Clinical Decision Rule for Blood Cultures in Community-Onset Methicillin-Resistant Staphylococcus aureus (MRSA) Skin and Soft Tissue Infections

Introduction

The emergence, spread and persistence of methicillin-resistant Staphylococcus aureus (MRSA) as a causative pathogen in community-onset (CO) skin and soft tissue infections (SSTIs) have resulted in substantial changes in the management of these infections. The indications for obtaining blood cultures in patients with CO-MRSA SSTIs remain poorly defined. The objectives of this study were to derive and validate a clinical decision rule that predicts the probability of MRSA bacteremia in CO-MRSA SSTIs and to identify a low-risk population for whom blood cultures may be safely omitted.

Methods

This was a retrospective, case-control study with an internal temporal validation cohort conducted at two large urban academic medical centers. Hospitalized adults with CO-MRSA SSTI between 2010 and 2018 were included. Independent predictors of MRSA bacteremia were identified through multivariable logistic regression. A decision rule was derived using weighted coefficient-based scoring. The decision rule was validated in an internal temporal validation cohort.

Results

A total of 307 patients (155 cases and 152 controls) were included in the derivation cohort. A decision rule was created with a “major criterion” defined as purulent cellulitis and “minor criteria” defined as abnormal temperature, intravenous drug use, leukocytosis, tachycardia, body mass index < 25 kg/m² and non-upper extremity infection site. A blood culture is indicated by this rule for patients with one major or at least two minor criteria. Otherwise patients are classified as low risk, and blood cultures may be omitted. The sensitivity of the decision rule in the derivation and validation cohorts was 98.71% (95% CI 95.42%, 99.84%) and 95.65% (78.05%, 99.89%), respectively. The specificity was 23.03% (95% CI 16.59%, 30.54%) and 30.77% (95% CI 24.15%, 38.02%), respectively.

Conclusion

The decision rule developed and validated in this study provides a standardized, evidenced-based approach to determine the need for blood cultures based on bacteremia risk.

Procalcitonin is not an independent predictor of 30-day mortality, albeit predicts pneumonia severity in patients with pneumonia acquired outside the hospital

Background

Procalcitonin (PCT) is a useful marker for pneumonia. However, its clinical usefulness in elderly patients has not been studied extensively. This study aimed to assess the relationship between PCT and prognosis and pneumonia severity in elderly patients with pneumonia acquired outside the hospital.

Methods

Data considered relevant to pneumonia severity and prognosis were retrospectively obtained from clinical charts of all patients with pneumonia who were admitted to our hospital from 2010 to 2017. The primary outcome was 30-day mortality in elderly patients (aged ≥75 years), and the relationship between PCT levels and pneumonia severity, as determined by the pneumonia severity index (PSI) was also examined.

Results

Data were collected from 667 patients, of which 436 were elderly patients. Multivariate and receiver operating characteristic curve analysis revealed that albumin, body mass index, and PSI class rather than PCT are important factors related to 30-day mortality in elderly patients. PCT was also not an independent prognostic factor in younger patients. PCT levels significantly differed by pneumonia severity (mild, moderate, and severe) in both younger (p < 0.001) and elderly (p < 0.0001) patients, with levels increasing as severity increased. In contrast, C-reactive protein (CRP) levels and white blood cell counts did not significantly differ by pneumonia severity in younger and elderly patients. A subgroup analysis focused on Streptococcus pneumoniae pneumonia revealed that PCT levels differed by severity in elderly patients (p = 0.03), with levels increasing as severity increased.

Conclusion

PCT was not an independent predictor of 30-day mortality in both of elderly and younger patients. PCT levels, but not CRP levels, significantly increased with increasing pneumonia severity in younger and elderly patients, although the degree of increase tended to be lower in elderly patients compared to younger patients for the same severity. PCT levels also significantly increased with increasing pneumonia severity in elderly patients with Streptococcus pneumoniae pneumonia.