Influence of Obesity Diagnosis With Organ Dysfunction, Mortality, and Resource Use Among Children Hospitalized With Infection in the United States

Association of Peripartum Lactate Levels With Infection Outcomes

OBJECTIVE

To determine whether lactate levels were associated with maternal infection and infection-related outcomes in the antepartum, intrapartum, and early postpartum periods.

DESIGN

Retrospective, observational cohort.

SETTING

Eleven hospitals from a single health system.

PARTICIPANTS

Women (N = 783) with at least one lactate and blood culture test for obstetric sepsis screening in the antepartum period (n = 154), intrapartum period (n = 348), and early postpartum period (n = 281) from January 2, 2018, to October 21, 2020.

METHODS

We reported the proportion of participants with adverse outcomes by lactate cut points (≤2.0 and >2.0 mmol/L). We used logistic regression to model the association of infection-related outcomes with lactate levels and calculated receiver operating characteristic curves.

RESULTS

Lactate was associated with bacteremia among participants in the antepartum period (odds ratio [OR] = 1.60, 95% confidence interval [CI] [1.00, 2.56]) but not among participants in the intrapartum and early postpartum periods. Higher lactate levels were significantly associated with a composite measure of infection-related outcomes (OR = 1.41, 95% CI [1.14, 1.81]), with no differential association by antepartum, intrapartum, or early postpartum periods. Lactate levels were positively associated with intraamniotic infection in the antepartum period (OR = 1.57, 95% CI [1.06, 1.81]) but not in the intrapartum period. The receiver operating characteristic curve indicated that the lactate threshold of 2.0 mmol/L has poor sensitivity. Overall, participants in the antepartum period had lower lactate values than participants in the intrapartum and early postpartum periods.

CONCLUSION

Lactate levels were not consistently associated with infection-related measures across all periods. We suggest caution when interpreting lactate levels when sepsis is suspected.

Obesity Alters cytokine signaling and gut microbiome in septic mice

Sepsis is a leading cause of mortality. Plasma cytokine levels may identify those at increased risk of mortality from sepsis. Our aim was to understand how obesity alters cytokine levels during early sepsis and its correlation with survival. Six-week-old C57BL/6 male mice were randomized to control (non-obese) or high fat diet (obese) for 5-7 weeks. Sepsis was induced by cecal ligation and perforation (CLP). Cytokine levels were measured from cheek bleeds 8 h after CLP, and mice were monitored for survival. Other cohorts were sacrificed 1 h after CLP for plasma and tissue. Septic obese mice had higher survival. At 8 h after sepsis, obese mice had higher adiponectin, leptin, and resistin but lower TNFα and IL-6 compared to non-obese mice. When stratified by 24-h survival, adipokines were not significantly different in obese and non-obese mice. TNFα and IL-6 were higher in non-obese, compared to obese, mice that died within 24 h of sepsis. Diet and to sepsis significantly impacted the cecal microbiome. IL-6 is a prognostic biomarker during early sepsis in non-obese and obese mice. A plausible mechanism for the survival difference in non-obese and obese mice may be the difference in gut microbiome and its evolution during sepsis.

Potential therapeutic implications of calcitriol administration and weight reduction on CD4 T cell dysregulation and renin angiotensin system-associated acute lung injury in septic obese mice

This study investigated the effects of weight reduction and/or calcitriol administration on regulating CD4 T cell subsets and renin-angiotensin system (RAS)-associated acute lung injury (ALI) in obese mice with sepsis. Half of the mice were fed a high-fat diet for 16 weeks, half of them had high-fat diet for 12 weeks then were transferred to a low-energy diet for 4 weeks. After feeding the respective diets, cecal ligation and puncture (CLP) were performed to induce sepsis. There were four sepsis groups: OSS group, obese mice injected with saline; OSD group, obese mice given calcitriol; WSS group, mice with weight reduction and saline; WSD group, mice with weight reduction and calcitriol. Mice were sacrificed after CLP. The findings showed that CD4 T subsets distribution did not differ among the experimental groups. Calcitriol-treated groups had higher RAS-associated AT2R, MasR, ACE2, and angiopoietin 1-7 (Ang(1-7)) levels in the lungs. Also, higher tight junction proteins were noted 12 h after CLP. At 24 h post-CLP, weight reduction and/or calcitriol treatment reduced plasma inflammatory mediator production. Calcitriol-treated groups had higher CD4/CD8, T helper (Th)1/Th2 and lower Th17/regulatory T (Treg) ratios than the groups without calcitriol. In the lungs, calcitriol-treated groups had lower AT1R levels, whereas the RAS anti-inflammatory protein levels were higher than those groups without calcitriol. Lower injury scores were also noted at this time point. These findings suggested weight reduction decreased systemic inflammation. However, calcitriol administration produced a more-balanced Th/Treg distribution, upregulated the RAS anti-inflammatory pathway, and attenuated ALI in septic obese mice.

SEX-DEPENDENT EFFECTS OF ADIPOCYTE STAT3 INHIBITION ON THE INFLAMMATORY RESPONSE DURING SEVERE SEPSIS

ABSTRACT

Introduction: Sepsis is a dysregulated host response to infection that can lead to life-threatening organ dysfunction. Clinical and animal studies consistently demonstrate that female subjects are less susceptible to the adverse effects of sepsis, demonstrating the importance of understanding how sex influences sepsis outcomes. The signal transducer and activator of transcription 3 (STAT3) pathway are a major signaling pathway that facilitates inflammation during sepsis. STAT3 is abundantly expressed in white adipose tissue; however, little is known about the contribution of white adipose tissue STAT3 activation during sepsis. We hypothesize that adipocyte STAT3 inhibition during severe sepsis will exaggerate the inflammatory response and impact organ injury, in a sex-dependent manner. Methods: We generated STAT3 flox/flox (wild-type [WT]) and adipocyte STAT3 knock out (A-STAT3 KO) mice using Cre-lox technology. Studies were done in 12- to 16-week-old male and female mice. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP). Control nonseptic mice did not undergo CLP (0 h CLP). Tissues were harvested 18 h after CLP. Body composition was determined by echo magnetic resonance imaging. Energy metabolism was determined by indirect calorimetry. White adipose tissue morphology was determined by hematoxylin and eosin staining, while STAT3 activation in the white adipose tissue was determined by western blot analysis and immunohistochemistry staining of STAT3 activation/phosphorylation at tyrosine 705. Plasma cytokines (TNF-α, IL-6, and leptin) were determined by luminex assay. Neutrophil infiltration of the lung and liver was assessed by myeloperoxidase activity assay. Histological signs of organ injury on lung and liver tissue were assessed by hematoxylin and eosin staining. Liver injury was further assessed by measuring plasma alanine and aspartate aminotransferase. In a separate cohort of mice, sepsis was induced by CLP and mice were monitored every 6-12 h over a 7-day period to assess survival rate. Results: We demonstrate that neither body composition nor energy metabolism is altered with adipocyte STAT3 inhibition in male or female mice, under nonseptic conditions. Sepsis was associated with reduced adipocyte size in female WT and A-STAT3 KO mice, suggesting that this event is STAT3 independent. Sepsis did not alter adipocyte size in male WT and A-STAT3 KO mice, suggesting that this event is also sex dependent. Although STAT3 phosphorylation at tyrosine 705 expression is negligible in male and female A-STAT3 KO mice, septic female WT and A-STAT3 KO mice have higher white adipose tissue STAT3 activation than male WT and A-STAT3 KO mice. Adipocyte STAT3 inhibition did not alter the proinflammatory cytokine response during sepsis in male or female mice, as measured by plasma TNF-α, IL-6, and leptin levels. Adipocyte STAT3 inhibition reduced lung neutrophil infiltration and histological signs of lung injury during sepsis in male mice. On the contrary, adipocyte STAT3 inhibition had no effect on lung neutrophil infiltration or lung injury in female mice. We further demonstrate that neither liver neutrophil infiltration nor histological signs of liver injury are altered by adipocyte STAT3 inhibition during sepsis, in male or female mice. Lastly, adipocyte STAT3 inhibition did not affect survival rate of male or female mice during sepsis. Conclusions: Our study demonstrates that sex influences white adipose tissue STAT3 activation and morphology during sepsis, which is not dependent on the presence of functional STAT3 in mature adipocytes. Furthermore, genetic inhibition of adipocyte STAT3 activation in male, but not female mice, results in reduced lung neutrophil infiltration and lung injury during sepsis. The results from our study demonstrate the importance of considering biological sex and the white adipose tissue as potential sources and targets of inflammation during sepsis.

Inpatient medical management of severe pediatric obesity: Literature review and case reports

Pediatric obesity rates continue to rise steeply with significant adverse effects on health outcomes across the lifespan. Significant obesity can affect the efficacy, side effects, and ability to use certain treatment, medication, or imaging modalities needed in the evaluation and management of acute pediatric conditions. Inpatient settings are rarely used as an opportunity for weight counseling and thus there is a paucity of clinical guidelines on how to manage severe obesity in the inpatient setting. We present a literature review and three patient cases with single-center protocol for non-surgical management of severe obesity in children admitted for other acute medical reasons. We performed a PubMed review from January 2002 to February 2022 utilizing keywords: "inpatient," "obesity," and "intervention." For our cases, we identified three patients with severe obesity acutely impacting their health while admitted for medical treatment who concurrently underwent acute, inpatient, weight loss regimens at a single children's hospital. The literature search yielded 33 articles describing inpatient weight loss treatments. Three patients met case criteria, all three of which demonstrated a decrease in their weight in excess percent of the 95th percentile after inpatient weight-management protocol implementation (% reduction BMI_p95: 16%-30%). This highlights obesity acutely limits or impacts specific medical care required during inpatient admissions in pediatric patients. It also suggests that implementation of an inpatient weight-management protocol during admission may provide an opportune setting to support acute weight loss and overall improved health outcomes in this high-risk cohort.

Clinical Outcome and Antibiotic Dosing Differences by Weight in Children With Acute Osteomyelitis

OBJECTIVES

To evaluate for weight-based differences in clinical outcomes and antibiotic dosing variability for children hospitalized with acute hematogenous osteomyelitis (AHO).

METHODS

We performed a retrospective cohort study of children aged 2 to 17 years and hospitalized with a primary AHO International Classification of Diseases, Ninth Revision or International Classification of Diseases, 10th Revision diagnosis code between 2010 and 2017 using the Cerner Health Facts database. Weight categories (healthy, overweight, obesity) were determined by using Centers for Disease Control and Prevention age- and sex-specific BMI percentiles. Rates of procedures, complications, and length of stay (LOS) were compared between groups. Dosing variability between groups was assessed by comparing the initial milligrams per kilogram per day of prescribed antibiotics.

RESULTS

We identified 755 children with AHO for inclusion. Children with overweight and obesity were more likely to undergo surgical procedures (19% and 17%, respectively) compared with children with a healthy weight (10%; P = .009). They also had a longer LOS (5.7 and 5.8 days) than children with a healthy weight (4.9 days; P = .03). There were no differences in complication rates between weight categories. Mean weight-adjusted daily dose for the most frequently prescribed antibiotics was different by weight category, with children in higher weight categories more likely to receive lower weight-based doses.

CONCLUSIONS

Children with overweight and obesity hospitalized for AHO were more likely to undergo procedures, have longer LOS, and receive lower weight-based antibiotic dosing compared with children with a healthy weight. Our findings suggest that weight should be carefully considered when treating children with AHO.

Effect of obesity on mortality among hospitalized paediatric patients with severe sepsis

INTRODUCTION

Severe sepsis is one of the leading causes of mortality among children. Studies in adults have suggested a protective effect of obesity on mortality among patients hospitalized with sepsis. Paediatric studies evaluating similar relationship is lacking.

METHODS

We analysed non-overlapping years of the Kids Inpatient Database (KID) and National Inpatient Sample (NIS) database between 2003 and 2014 of all paediatric patients with severe sepsis (PSS) up to 20 years of age. PSS was defined using specific International Classification of Diseases (ICD) codes and modified Angus criteria. Using ICD-9 diagnosis codes, patients were divided into three mutually exclusive groups (obesity, morbid obesity and control groups), and these groups were compared for outcomes measures including in-hospital mortality and healthcare resource utilization using the length of stay and inflation-adjusted hospitalization charges.

RESULTS

We analysed 109 026 hospitalizations due to PSS. The prevalence rate of obesity was 1.5% (n = 1643), and morbid obesity was 1.05% (n = 1147). Multivariate regression models showed obesity was associated with 63% (OR 0.37, CI: 0.29-0.47, p < 0.001) and 54% reduction in mortality among PSS patients and patients with septic shock respectively. Contrastingly, morbid obesity was not associated with mortality among PSS patients and but was associated with 1.37 times (CI: 1.06-1.78, p = 0.01) increased risk of mortality among paediatric patients with septic shock.

CONCLUSIONS

Paediatric obesity is associated with reduced mortality among patients with PSS, with the exception of morbid obesity. Further prospective studies are needed to better understand the relationship between obesity and outcomes in PSS.

The Impact of Malnutrition on Hospitalized Children With Cerebral Palsy

Children with cerebral palsy (CP) and other medical complexity comprise an outsized proportion of health care use. In this review, we describe the current science of assessment of nutritional status for children with CP, outline a systematic approach to assessing their nutritional status, delineate ramifications of malnutrition on hospitalization-associated outcomes, and identify knowledge gaps and means of addressing those gaps using quality improvement and clinical research tools. Methods to accurately assess body composition and adiposity in this population by using skinfolds, age, sex, and activity level are available but are not widely used. There are limitations in our current method of estimating energy needs in children with CP, who are at higher risk of both obesity and micronutrient deficiencies. There is some evidence of an association between malnutrition, defined as either underweight or obesity, and hospitalization-associated outcomes in children generally, although we lack specific data for CP. The gaps in our current understanding of optimal nutritional status and between current science and practice need to be addressed to improve health outcomes for this vulnerable patient population.

The Collision of Meta-Inflammation and SARS-CoV-2 Pandemic Infection

The coronavirus disease 2019 (COVID-19) pandemic has forced us to consider the physiologic role of obesity in the response to infectious disease. There are significant disparities in morbidity and mortality by sex, weight, and diabetes status. Numerous endocrine changes might drive these varied responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, including hormone and immune mediators, hyperglycemia, leukocyte responses, cytokine secretion, and tissue dysfunction. Studies of patients with severe COVID-19 disease have revealed the importance of innate immune responses in driving immunopathology and tissue injury. In this review we will describe the impact of the metabolically induced inflammation (meta-inflammation) that characterizes obesity on innate immunity. We consider that obesity-driven dysregulation of innate immune responses may drive organ injury in the development of severe COVID-19 and impair viral clearance.

Sepsis Patients in Critical Care Units with Obesity: Is Obesity Protective?

Obesity is becoming a global health issue and its prevalence is increasing. It is associated with an increased incidence of illness and sepsis. While obesity is associated with increased morbidity and mortality, obesity has been found to be associated with improvement in mortality outcomes in sepsis when compared to leaner patients, a phenomenon described as an obesity paradox. However, the effect of obesity on mortality in adults requiring treatment for sepsis is unclear. Studies evaluating this effect are inconsistent and there is an increased morbidity still associated with obesity. As well, there are many limitations to these studies confounding interpretation. Future prospective studies minimizing bias and confounding factors are suggested to address this important clinical issue.

Prevalence and Trends in Obesity Among Hospitalized Children

OBJECTIVES

As obesity rates rise in children, it is likely that the number of hospitalized children with obesity is also increasing. However, characterization of the inpatient population with obesity as a whole has not been reported. We aimed to examine trends in the annual prevalence of obesity in hospitalized children and to identify demographic and clinical characteristics associated with higher obesity prevalence in children who are hospitalized.

METHODS

We completed a retrospective cohort analysis of children aged 2 to 19 years admitted to a single tertiary children's hospital system for any reason in 2009-2016. Body mass index was calculated from documented height and weight. Children with obesity were defined by using age- and sex-specific body mass index percentile guidelines established by the Centers for Disease Control and Prevention. Annual obesity prevalence was calculated on the encounter level for service line and All Patients Refined Diagnosis-Related Groups (diagnosis groups). χ² tests were used to determine statistical differences between groups, and the Cochran-Armitage test of trend was used to describe changes in obesity over time.

RESULTS

Of 83 329 children who were hospitalized, 17.0% had obesity, increasing from 16.5% of hospitalizations in 2009-2010 to 17.3% in 2015-2016 (P = .002). Service lines with the highest obesity prevalence included orthopedics (22.1%), infectious disease (20.6%), and neuroscience (18.7%). Diagnosis groups with the highest obesity prevalence included cellulitis (22.5%), tonsil/adenoid procedures (22.0%), and some orthopedic procedures (28.7%).

CONCLUSIONS

Some groups of children who were hospitalized experience higher obesity prevalence, including children hospitalized with orthopedic, infectious disease, and neurologic problems. In future research, investigators should target disproportionately affected groups by examining health outcomes, patient safety, and satisfaction issues.

Body Habitus and Risk of Mortality in Pediatric Sepsis and Septic Shock: A Retrospective Cohort Study

OBJECTIVE

To investigate the association between body habitus and mortality in critically ill children with sepsis or septic shock.

STUDY DESIGN

This was a retrospective cohort study of prospectively collected data of children admitted to US pediatric intensive care units (PICUs) with a primary or secondary diagnosis of sepsis or septic shock. We separated body habitus into underweight, normal weight, overweight, and obese. Outcomes were mortality (primary), treatment with invasive mechanical ventilation (secondary), and time to PICU discharge for survivors (secondary). Multivariable analyses using mixed-effects logistic regression and shared frailty models clustered by unit and adjusted for confounding variables were used to assess the association between body habitus and outcomes.

RESULTS

There were 7038 children with sepsis or septic shock. Mortality was 10.1% (n = 714) and 52.9% (n = 3720) required invasive mechanical ventilation. Body habitus was not associated with mortality after controlling for hospital level effects and confounding variables. Children who were overweight and obese had greater odds of invasive mechanical ventilation (overweight OR 1.23 [95% CI 1.05-1.45], P = .011 and obese OR 1.57 [95% CI 1.37-1.80], P < .001) compared with children of normal weight. In survivors treated with invasive mechanical ventilation, children who were obese had a longer time to PICU discharge than children of normal weight (obese hazard ratio for discharge 0.84 [95% CI, 0.77-0.92], P < .0001).

CONCLUSIONS

There was no association between body habitus and mortality in critically ill children with sepsis. Children who were overweight and obese were more likely to receive invasive mechanical ventilation and mechanically ventilated survivors who were obsese had a longer time to PICU discharge.

Outcomes and Resource Use Among Overweight and Obese Children With Sepsis in the Pediatric Intensive Care Unit

OBJECTIVE

To evaluate the effect of overweight and obesity on outcomes and resource use among patients with sepsis in the pediatric intensive care unit (PICU).

DESIGN

Retrospective analysis of clinical characteristics, resource use, and mortality among children 0 to 20 years of age admitted to the C.S. MottChildren's Hospital PICU (University of Michigan) between January 2009 and December 2015, with a diagnostic code for sepsis at admission (based on International Classification of Diseases, Ninth Revision-Clinical Modification codes) and with weight and height measurements at PICU admission.

MEASUREMENTS AND MAIN RESULTS

A total of 454 participants met the inclusion criteria. Seventy-six were categorized as underweight (body mass index [BMI] percentile <5th) and were excluded, which left a final sample size of 378 participants. Children with a BMI >5th and <85th percentiles for age were categorized as normal weight and those with a BMI >85th percentile as overweight/obese. After descriptive and bivariate analyses, multivariate regression methods were used to assess the independent effect of obesity status on mortality and the use of PICU technology after adjustment for patient age and illness severity at admission. Of the 378 patients studied, 41.3% were overweight/obese. There was no difference in microbiologic etiology of sepsis (P = .36), median PICU length of stay in days (5.4 vs 5.6; P = .61), or PICU mortality (6.4% vs 7.2%; P = .76) by weight status. The use of specialized PICU technology including extracorporeal membrane oxygenation (odds ratio [OR]: 2.77, 95% confidence interval [CI]:1.13-6.79) and continuous renal replacement therapy (OR: 4.58, 95% CI: 1.16-18.0) was higher among overweight/obese patients, compared with normal weight patients.

CONCLUSIONS

Although PICU mortality and length of stay were similar for obese-overweight patients and normal weight critically ill children with sepsis, there was significantly higher use of specialized organ-supportive technology among obese patients, likely indicating higher occurrence of multiple organ dysfunction.