Burn mortality in patients with preexisting cardiovascular disease

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Chronic kidney disease and cardiovascular disease reduce survival rates after burn injury: A retrospective study over 20 years

BACKGROUND

The Abbreviated Burn Severity Index and comparable scores are used to assess the probability of survival in burned patients. These scores may be useful during the initial management of the patient and in addition to the clinical evaluation. As current models do not include the influence of chronic diseases, we evaluated the impact of comorbidities on survival probability, aiming to improve the existing scoring systems and survival probability accuracy further.

METHODS

In this retrospective single-center study, patient data from a center for Severe Burn Injury were collected. Over a period of 20 years (2000-2019), a total of 1,193 patients were recorded. The influence of comorbidities (chronic kidney disease, diabetes mellitus type II, and cardiovascular diseases) on the survival probability was analyzed using regression models. These analyses were stratified for sex and period.

RESULTS

Pre-existing chronic kidney disease, as well as pre-existing cardiovascular disease, had a significant influence on the survival of patients. For chronic kidney disease, the influence was stronger in men than in women. Women were more likely to survive a burn injury with a history of chronic renal insufficiency. An improved Abbreviated Burn Severity Index model, which assigns an additional point for chronic kidney disease, best-described survival probability in our patient cohort.

CONCLUSION

Cardiovascular disease and chronic kidney disease both have an impact on the survival probability of severely burned patients, but this impact is more severe for chronic kidney disease. An additional Abbreviated Burn Severity Index point for chronic kidney disease would be a proposed adaptation to predict the outcome of burn patients better.

Adult Burn Inpatients Have Increased Burn Severity and Mortality Compared to Children in Retrospective Analysis of National Inpatient Sample 2017

INTRODUCTION

Socioeconomic status and comorbidities are associated with increased mortality in patients with external surface burn patients, however differences between pediatric and adult burn populations have not been adequately studied.

OBJECTIVES

Our objectives were to explore the presentation, management, and outcomes of external surface burns across age groups.

METHODS

The 2017 National Inpatient Sample (NIS) was queried for patients with any diagnosis of external body surface burns. Demographics, comorbidities, complications, total charges, length of stay (LOS), number of procedures undergone (NPU), and time from admission to first procedure (TFP) were identified. Univariate and multivariable analyses were used to identify statistical associations with age.

RESULTS

52,335 inpatients were identified with burns, with the majority male (63.6%) and adults (81.8%). Mean age was 50.5 (standard error [SE] 0.1) and 5.5 (SE 0.1) years for adults and children, respectively. Adults had higher prevalence of hypertensive disease (43.5% versus. 1.4%), diabetes mellitus (24.1% versus 0.3%), and obesity (11.7% versus 1.6%) than children (P < 0.001). Adults versus children had higher odds for mortality (odds ratio [OR] 4.26, 95% confidence interval [CI] 3.08-5.89), sepsis (OR 5.16, 95% CI 4.10-6.48), and pneumonia (OR 4.26, 95% CI 3.30-5.50).

CONCLUSIONS

In this national cohort of inpatients with external surface burns, comorbidities, and odds for mortality and complications varied by age. Pediatric patients more often had lower household incomes; however, adults had significantly higher odds for mortality suggesting that age and comorbidity status are more impactful on burn outcomes than socioeconomic status.

Epidemiology and mortality in patients hospitalized for burns in Catalonia, Spain

Burn injuries are one of the leading causes of morbidity worldwide. Although the overall incidence of burns and burn-related mortality is declining, these factors have not been analysed in our population for 25 years. The aim of this study has been to determine whether the epidemiological profile of patients hospitalized for burns has changed over the past 25 years. We performed a retrospective cohort study of patients hospitalised between 1 January 2011 and 31 December 2018 with a primary diagnosis of burns. The incidence of burns in our setting was 3.68/105 population. Most patients admitted for burns were men (61%), aged between 35 and 45 years (16.8%), followed by children aged between 0 and 4 years (12.4%). Scalding was the most prevalent mechanism of injury, and the region most frequently affected was the hands. The mean burned total body surface (TBSA) area was 8.3%, and the proportion of severely burned patients was 9.7%. Obesity was the most prevalent comorbidity (39.5%). The median length of stay was 1.8 days. The most frequent in-hospital complications were sepsis (16.6%), acute kidney injury (7.9%), and cardiovascular complications (5.9%). Risk factors for mortality were advanced age, high abbreviated burn severity index score, smoke inhalation, existing cardiovascular disease full-thickness burn, and high percentage of burned TBSA. Overall mortality was 4.3%. Multi-organ failure was the most frequent cause of death, with an incidence of 49.5%. The population has aged over the 25 years since the previous study, and the number of comorbidities has increased. The incidence and severity of burns, and the percentage of burned TBSA have all decreased, with scalding being the most prevalent mechanism of injury. The clinical presentation and evolution of burns differs between children and adults. Risk factors for mortality were advanced age, smoke inhalation, existing cardiovascular disease, full-thickness burn, and high percentage of burned TBSA.

Predicting and Estimating Burn Outcomes: An Institutional Analysis of 4622 cases

Advances in burn care have improved patient outcomes, and independently validated indices and predictors of burn outcomes warrant re-evaluation. The purpose of this study is to consolidate predictors of burn outcomes and determine the factors that significantly contribute to length-of-stay (LOS) and mortality. A retrospective review was conducted of all burn patients (n=5778) admitted to a quaternary provincial burn unit from 1973 to 2017. Our inclusion criteria yielded 4622 independent cases. Multivariate linear and logistic regression models were generated, and area-under-receiver-operator-curve (AUROC) analysis was performed. Burn predictors included %TBSA, Baux (classic and revised) index, Abbreviated Burn Severity Index (ABSI), and Ryan score. Primary outcomes were mortality and LOS. Multivariate logistic regression for mortality showed the Baux index to be the best predictor for mortality (OR=1.11, p<0.001). The AUROC for Baux index was 0.95. With regards to LOS, ABSI was the best predictor for LOS (p<0.001). ICU stay, ventilator use, alcoholism, age, significantly associated with increased LOS. Interestingly, hypertension had a protective effect for LOS (p<0.01) and trended towards a protective effect in mortality. Lethal score 50% (LS50) improved over the study period. The regressions show that burn mortality and LOS are best predicted with the Baux index and ABSI, respectively. Hypertension may have a protective effect on burn outcomes and may be attributed to increased perfusion to the periphery. These predictive scores are useful in determining institutional outcomes in burn surgery. Objective benchmarking of improvement in burn care outcomes can be established using LS50 trends.

Age-dependent influence of premorbid underweight status on mortality in severe burn patients: An administrative database study

PURPOSE

To examine the associations between premorbid nutritional status and in-hospital mortality in severe burn patients according to age in Japan.

METHODS

We retrospectively extracted the data of 14,345 patients aged 18-84 years admitted for burns from April 1, 2014, to March 31, 2018, using the Japanese Diagnosis Procedure Combination database. The exclusion criteria were out-of-hospital cardiac arrest, death in the emergency room, readmission, and planned admission. We collected data on age, sex, height, weight, comorbidities, burn index, and mechanical ventilation use and performed age-stratified multilevel logistic regression analyses to estimate associations between premorbid body mass index (BMI) and in-hospital mortality.

RESULTS

We analyzed 2968 patients with a burn index ≥10, including 831 elderly aged 75-84 years. In patients aged 18-74 years, being underweight (BMI < 18.5) significantly decreased mortality (0.34 [0.15-0.77]; P = 0.010). In contrast, in patients aged 75-84 years, being underweight significantly increased mortality (2.11 [1.05-4.25]; P = 0.036). Being overweight (BMI >25) increased mortality in both age groups, but not significantly.

CONCLUSIONS

The results suggest that pre-morbidly underweight elderly patients aged 75-84 years with severe burns have high mortality risks. Further research is needed to identify optimal care strategies for this population.

Sex-Based Differences in Inpatient Burn Mortality

BACKGROUND

Among burn patients, research is conflicted, but may suggest that females are at increased risk of mortality, despite the opposite being true in non-burn trauma. Our objective was to determine whether sex-based differences in burn mortality exist, and assess whether patient demographics, comorbid conditions, and injury characteristics explain said differences.

METHODS

Adult patients admitted with burn injury-including inhalation injury only-between 2004 and 2013 were included. Inverse probability of treatment weights (IPTW) and inverse probability of censor weights (IPCW) were calculated using admit year, patient demographics, comorbid conditions, and injury characteristics to adjust for potential confounding and informative censoring. Standardized Kaplan-Meier survival curves, weighted by both IPTW and IPCW, were used to estimate the 30-day and 60-day risk of inpatient mortality across sex.

RESULTS

Females were older (median age 44 vs. 41 years old, p < 0.0001) and more likely to be Black (32% vs. 25%, p < 0.0001), have diabetes (14% vs. 10%, p < 0.0001), pulmonary disease (14% vs. 7%, p < 0.0001), heart failure (4% vs. 2%, p = 0.001), scald burns (45% vs. 26%, p < 0.0001), and inhalational injuries (10% vs. 8%, p = 0.04). Even after weighting, females were still over twice as likely to die after 60 days (RR 2.87, 95% CI 1.09, 7.51).

CONCLUSION

Female burn patients have a significantly higher risk of 60-day mortality, even after accounting for demographics, comorbid conditions, burn size, and inhalational injury. Future research efforts and treatments to attenuate mortality should account for these sex-based differences. The project was supported by the National Institutes of Health, Grant Number UL1TR001111.

Effect of comorbidities on clinical outcome of patients with burn injury - An analysis of the German Burn Registry

BACKGROUND

Severe burn injuries are associated with high morbidity and mortality. Well-implemented scoring systems for patients with major burns exist in the literature. A major disadvantage of these scores is the partial non-consideration of patient-related comorbidities. Published data on this matter is limited to small study cohorts and/or single center studies. Further, the effect of comorbidities on clinical outcome of patients with severe burn injuries has not yet been examined nationwide in a large cohort in Germany. Hence, the aim of this study was to examine the influence of comorbidities on clinical outcome of these patients based on data from the national registry.

METHODS

Anonymized data from a total of 3455 patients with documented burns of 1% or more Total Burn Surface Area (TBSA) and over 16 years of age included in the German Burn Registry between 2017 and 2018 were analyzed retrospectively. Data included burn extent, body weight, age, burn depth, inhalation injury, comorbidities, mortality, number of operations and length of hospital stay (LOS).

RESULTS

In the logistic regression analysis age (OR 1.07 [1.06-1.09], p < 0.001), TBSA (OR 1.09 [1.08-1.11], p < 0.001), IHT (OR 2.15 [1.44-3.20], p < 0001), third degree burn (OR 2.08 [1.39-3.11], p < 0.001), Chronic Obstructive Pulmonary Disease (COPD) (OR 2.45 [1.38-4.35], p = 0.002) and renal insufficiency (OR 2.02 [1.13-3.59], p = 0.017) influenced mortality significantly. If a patient had more than one comorbidity, mortality was higher and in-hospital length of stay (LOS) longer. Renal insufficiency was significantly (p < 0.001) associated with the most prolonged LOS by 11.44 days. TBSA (p < 0.001), Abbreviated Burn Severity Index (ABSI) > 3 (p < 0.001) and IHT (p = 0.001) correlated with the amount of required surgeries and significantly predicted the need for intubation. Patients with arrhythmia significantly required more surgeries (p = 0.041), whereas patients with COPD required significantly less surgical interventions (p = 0.013).

CONCLUSION

Preexisting comorbidities have a significant impact on the clinical outcome of patients with severe burn injuries. Further investigation is warranted in order to supplement existing prognostic scores with new mortality-associated parameters.