Associations between low body mass index and mortality in patients with sepsis: A retrospective analysis of a cohort study in Japan

Obesity and septic patient outcomes: Shaping the puzzle through age and sex perspectives

BACKGROUND & AIMS

While obesity has been reported as a protective factor in septic patients, little is known about the potential modifying effects of age and sex. The objective of this study is to investigate age and sex-specific associations between obesity and the prognosis of septic patients.

METHODS

A retrospective analysis was conducted on a cohort of 15,464 septic patients, categorized by body mass index (BMI) into four groups: underweight (<18.5 kg/m2, n = 483), normal (18.5-24.9 kg/m2, n = 4344), overweight (25-29.9 kg/m2, n = 4949) and obese (≥30 kg/m2, n = 5688). Multivariable logistic regression and inverse probability weighting were employed to robustly confirm the protective effect of a higher BMI on 28-day mortality, with normal weight serving as the reference category. Subgroup analyses based on age (young: 18-39, middle-aged: 40-64 and elderly: ≥65) and sex were performed.

RESULTS

The findings demonstrate that high BMI independently confers a protective effect against 28-day mortality in septic patients. However, the relationship between BMI and 28-day mortality exhibits a non-linear trend, with a BMI of 34.5 kg/m2 displaying the lowest odds ratio. Notably, the survival benefits associated with a high BMI were not observed in the young group. Moreover, being underweight emerges as an independent risk factor for middle-aged and elderly female patients, while in males it is only a risk factor in the elderly group. Interestingly, being overweight and obese were identified as independent protective factors in middle-aged and elderly male patients, but not in females.

CONCLUSIONS

The effect of BMI on mortality in septic patients varies according to age and sex. Elderly individuals with sepsis may derive more prognostic benefits from obesity.

Utility of Lean Body Mass Equations and Body Mass Index for Predicting Outcomes in Critically Ill Adults with Sepsis: A Retrospective Study

Lean body mass is a significant component of survival from sepsis. Several equations can be used for calculating lean body mass based on age, sex, body weight, and height. We hypothesized that lean body mass is a better predictor of outcomes than the body mass index (BMI). This study used a multicenter cohort study database. The inclusion criteria were age ≥18 years and a diagnosis of sepsis or septic shock. BMI was classified into four categories: underweight (<18.5 kg/m2), normal (≥18.5-<25 kg/m2), overweight (≥25-<30 kg/m2), and obese (≥30 kg/m2). Four lean body mass equations were used and categorized on the basis of quartiles. The outcome was in-hospital mortality among different BMI and lean body mass groups. Among 85,558 patients, 3916 with sepsis were included in the analysis. Regarding BMI, in-hospital mortality was 36.9%, 29.8%, 26.7%, and 27.9% in patients who were underweight, normal weight, overweight, and obese, respectively (p < 0.01). High lean body mass did not show decreased mortality in all four equations. In critically ill patients with sepsis, BMI was a better predictor of in-hospital mortality than the lean body mass equation at intensive care unit (ICU) admission. To precisely predict in-hospital mortality, ICU-specific lean body mass equations are needed.

Prognostic factors in mobility disability among elderly patients in the emergency department: A single-center retrospective study

Aim

We aimed to evaluate the clinical characteristics and outcomes of elderly critically ill patients and identify prognostic factors for mobility disability at discharge.

Methods

This single-center, retrospective cohort study investigated the period from April 2020 to January 2021. Patients ≥75 years old transferred to our emergency department and admitted to the intensive care unit (ICU) or intermediate unit in our hospital were eligible. Demographics, clinical characteristics, nutritional indicators, and nutritional screening scores were collected from chart reviews and analyzed. The primary outcome was the prevalence of mobility disability, compared to that of no mobility disability.

Results

A total of 124 patients were included in this present study. Median age was 83.0 years (interquartile range [IQR], 79.8-87.0 years) and 48 patients (38.7%) were female. Fifty-two patients (41.9%) could not walk independently at discharge (mobility disability group). The remaining 72 patients were in the no mobility disability group. Multiple logistic regression analyses revealed clinical frailty scale (CFS) score ≥5 (odds ratio [OR] = 6.63, 95% confidence interval [CI] = 2.51-17.52, p < 0.001), SOFA score ≥6 (OR = 6.11, 95% CI = 1.57-23.77, p = 0.009), and neurological disorder as the main cause on admission (OR = 4.48, 95% CI = 1.52-13.20, p = 0.006) were independent and significant prognostic factors for mobility disability at discharge.

Conclusion

Among elderly patients admitted to the emergency department, CFS ≥5, SOFA ≥6, and neurological disorders were associated with mobility disability at hospital discharge.

Diabetes-Related Mortality in a Developing Country: An Exploration of Tertiary Hospital Data

(1) Background: Given the growing global diabetes crisis, this study examined the causes of mortality in diabetic patients at a Mongolian tertiary care hospital. (2) Between 2017 and 2021, data from 100 individuals with diabetes (53% male, mean age 58.5 years, duration of diabetes, 9.6 years, HbA1c level, 9.7%, 11.1% type 1 diabetes) were reviewed. (3) Results: The predominant cause of mortality was sepsis, accounting for 65.0% of cases and emerging as a contributing factor in 75.0% of instances. Renal failure constituted the second leading cause of death, accounting for 19.0% of mortalities. Other contributing factors included chronic liver disease (6.0%) and ARDS (3.0%). Regarding sepsis, the individuals affected were relatively younger (57.5 ± 11.2 vs. 61.7 ± 11.2, p = 0.988), with a slightly higher prevalence among female patients (77.4%) and those with T1DM (81.8%), though these differences were not statistically significant (p > 0.05). Patients with sepsis exhibited lower BMI values (26.7 ± 4.1 vs. 28.5 ± 6.2, p = 0.014) and poorer glycemic control (9.8 ± 3.1 vs. 9.6 ± 5.1, p = 0.008); (4) Conclusions: This hospital-based data analysis in Mongolia highlights sepsis as the primary cause of mortality among diabetes patients in tertiary hospitals regardless of age, gender, or diabetes type while also indicating a potential association between a lower BMI, poor glycemic control, smoking, and the risk of sepsis.

Association of obesity and mortality in sepsis patients: A meta-analysis from observational evidence

The project aims to investigate the correlation between obesity, overweight, or low body weight and the risk of mortality in sepsis patients. We performed a rigorous and thorough search of major electronic databases, including PubMed, Web of Science, EMBASE, and Cochrane Library, from the inception of these databases up to March 28, 2023. The data were analyzed with Stata software (version 16.0). Twelve studies incorporating 521,207 individuals were enrolled. The results demonstrated that obesity (OR = 0.82; 95% CI: 0.69-0.97; P < 0.001) or overweight (OR = 0.83; 95% CI: 0.73-0.94; P < 0.001) decreased the risk of mortality in sepsis patients. Instead, the reverse phenomena existed in patients with a low weight (OR = 1.43; 95%CI: 1.16-1.76; P = 0.038). There is an "obesity paradox" phenomenon in the mortality of obese and overweight patients with sepsis, but low body weight is an independent risk factor for the mortality of sepsis patients. This study demonstrated that the mortality in sepsis patients and obesity or overweight were negatively correlated, but displayed a significant positive relation to low weight.

Association of body mass index with mortality of sepsis or septic shock: an updated meta-analysis

BACKGROUND

The effects of body mass index (BMI) on mortality of sepsis remain unknown, since previous meta-analyses have reported conflicting results. Several observational studies published recently have provided new evidence. Thus, we performed this updated meta-analysis.

METHODS

PubMed, Embase, Web of Science, and Cochran Library were searched for articles published before February 10, 2023. Observational studies that assessed the association of BMIs with mortality of sepsis patients aged > 18 years were selected. We excluded studies of which data were unavailable for quantitative synthesis. Odds ratios (OR) with 95% confidence interval (CI) were the effect measure, which were combined using fixed-effect or random-effect models. The Newcastle-Ottawa Scale was applied for quality assessment. Subgroups analyses were conducted according to potential confounders.

RESULTS

Fifteen studies (105,159 patients) were included in the overall analysis, which indicated that overweight and obese BMIs were associated with lower mortality (OR: 0.79, 95% CI 0.70-0.88 and OR: 0.74, 95% CI 0.67-0.82, respectively). The association was not significant in patients aged ≤ 50 years (OR: 0.89, 95% CI 0.68-1.14 and OR: 0.77, 95% CI 0.50-1.18, respectively). In addition, the relationship between morbidly obesity and mortality was not significant (OR: 0.91, 95% CI 0.62-1.32).

CONCLUSIONS

Overweight and obese BMIs (25.0-39.9 kg/m²) are associated with reduced mortality of patients with sepsis or septic shock, although such survival advantage was not found in all crowds. Trial registration The protocol of this study was registered in PROSPERO (registration number CRD42023399559).

Obesity Paradox and Functional Outcomes in Sepsis: A Multicenter Prospective Study

OBJECTIVES

In Asian populations, the correlation between sepsis outcomes and body mass is unclear. A multicenter, prospective, observational study conducted between September 2019 and December 2020 evaluated obesity's effects on sepsis outcomes in a national cohort.

SETTING

Nineteen tertiary referral hospitals or university-affiliated hospitals in South Korea.

PATIENTS

Adult patients with sepsis ( n = 6,424) were classified into obese ( n = 1,335) and nonobese groups ( n = 5,089).

MEASUREMENTS AND RESULTS

Obese and nonobese patients were propensity score-matched in a ratio of 1:1. Inhospital mortality was the primary outcome. After propensity score matching, the nonobese group had higher hospital mortality than the obese group (25.3% vs 36.7%; p < 0.001). The obese group had a higher home discharge rate (70.3% vs 65.2%; p < 0.001) and lower median Clinical Frailty Scale (CFS) (4 vs 5; p = 0.007) at discharge than the nonobese group, whereas the proportion of frail patients at discharge (CFS ≥ 5) was significantly higher in the nonobese group (48.7% vs 54.7%; p = 0.011). Patients were divided into four groups according to the World Health Organization body mass index (BMI) classification and performed additional analyses. The adjusted odds ratio of hospital mortality and frailty at discharge for underweight, overweight, and obese patients relative to normal BMI was 1.25 ( p = 0.004), 0.58 ( p < 0.001), and 0.70 ( p = 0.047) and 1.53 ( p < 0.001), 0.80 ( p = 0.095), and 0.60 ( p = 0.022), respectively.

CONCLUSIONS

Obesity is associated with higher hospital survival and functional outcomes at discharge in Asian patients with sepsis.

Association between low body temperature on admission and in-hospital mortality according to body mass index categories of patients with sepsis

Hypothermia has been shown to be associated with a high mortality rate among patients with sepsis. However, the relationship between hypothermia and body mass index (BMI) with respect to mortality remains to be elucidated. We conducted this study to assess the association between hypothermia and survival outcomes of patients with sepsis according to BMI categories. This secondary analysis of a prospective cohort study enrolled 1184 patients (aged ≥ 16 years) with sepsis hospitalized in 59 intensive care units in Japan. Patients were divided into 3 BMI categories (<18.5 [low], 18.5-24.9 [normal], >24.9 [high] kg/m2) and 2 body temperature (36 °C and ≥ 36 °C) groups. The primary outcome was in-hospital mortality rate. Associations between hypothermia and BMI categories with respect to in-hospital mortality were evaluated using multivariate logistic regression analysis. Of the 1089 patients, 223, 612, and 254 had low, normal, and high BMI values, respectively. Patients with body temperature < 36 °C (hypothermia) had a higher in-hospital mortality rate than that had by those without hypothermia in the normal BMI group (25/63, 39.7% vs. 107/549, 19.5%); however, this was not true for patients in the low or high BMI groups. A significant interaction was observed between hypothermia and normal BMI for in-hospital mortality (odds ratio, 1.56; 95% confidence interval, 1.00-3.41; P value for interaction = .04); however, such an interaction was not found between hypothermia and low or high BMIs. Patients with sepsis and hypothermia in the normal BMI subgroup may have a higher mortality risk than that of those in the low or high BMI subgroups and, therefore, require more attention.

Mortality risks associated with empirical antibiotic activity in Escherichia coli bacteraemia: an analysis of electronic health records

Background

Reported bacteraemia outcomes following inactive empirical antibiotics (based on in vitro testing) are conflicting, potentially reflecting heterogeneity in causative species, MIC breakpoints defining resistance/susceptibility, and times to rescue therapy.

Methods

We investigated adult inpatients with Escherichia coli bacteraemia at Oxford University Hospitals, UK, from 4 February 2014 to 30 June 2021 who were receiving empirical amoxicillin/clavulanate with/without other antibiotics. We used Cox regression to analyse 30 day all-cause mortality by in vitro amoxicillin/clavulanate susceptibility (activity) using the EUCAST resistance breakpoint (>8/2 mg/L), categorical MIC, and a higher resistance breakpoint (>32/2 mg/L), adjusting for other antibiotic activity and confounders including comorbidities, vital signs and blood tests.

Results

A total of 1720 E. coli bacteraemias (1626 patients) were treated with empirical amoxicillin/clavulanate. Thirty-day mortality was 193/1400 (14%) for any active baseline therapy and 52/320 (16%) for inactive baseline therapy (P = 0.17). With EUCAST breakpoints, there was no evidence that mortality differed for inactive versus active amoxicillin/clavulanate [adjusted HR (aHR) = 1.27 (95% CI 0.83–1.93); P = 0.28], nor of an association with active aminoglycoside (P = 0.93) or other active antibiotics (P = 0.18). Considering categorical amoxicillin/clavulanate MIC, MICs > 32/2 mg/L were associated with mortality [aHR = 1.85 versus MIC = 2/2 mg/L (95% CI 0.99–3.73); P = 0.054]. A higher resistance breakpoint (>32/2 mg/L) was independently associated with higher mortality [aHR = 1.82 (95% CI 1.07–3.10); P = 0.027], as were MICs > 32/2 mg/L with active empirical aminoglycosides [aHR = 2.34 (95% CI 1.40–3.89); P = 0.001], but not MICs > 32/2 mg/L with active non-aminoglycoside antibiotic(s) [aHR = 0.87 (95% CI 0.40–1.89); P = 0.72].

Conclusions

We found no evidence that EUCAST-defined amoxicillin/clavulanate resistance was associated with increased mortality, but a higher resistance breakpoint (MIC > 32/2 mg/L) was. Additional active baseline non-aminoglycoside antibiotics attenuated amoxicillin/clavulanate resistance-associated mortality, but aminoglycosides did not. Granular phenotyping and comparison with clinical outcomes may improve AMR breakpoints.