The role of biological sex in severely traumatized patients on outcomes: a matched-pair analysis

EFFECT OF GENDER ON 28-DAY SURVIVAL RATES AND TRANSFUSION VOLUME IN SEVERE TRAUMA PATIENTS: A MULTICENTER OBSERVATIONAL STUDY

ABSTRACT

Background: This study clarified the relationship between sex with survival and transfusion volume in severe trauma cases. Methods: A multicenter, collaborative post hoc analysis of patients with trauma in Japan was conducted. Patients aged ≥18 years with severe trauma indicated by an Injury Severity Score (ISS) of 16 or higher were enrolled. Patients were matched and analyzed by gender based on propensity score with factors determined at the time of injury. Subgroup analysis was performed on patients younger than 50 years and older than 50 years. The significance level was defined as P < 0.05. Results: The 1,189 patients included in this registry were divided into adjusted groups of 226 male and female patients each. In the main analysis, 28-day survival rates in females were significantly higher than those in males ( P = 0.046). In the subgroup analyses, there was no statistically significant prognostic effect of gender. Secondary outcomes, including transfusion volume, showed no significant gender-based variations. Logistic regression analyses consistently demonstrated that female sex was a significant favorable prognostic factor in all ages. This was true for the over-50 group on subgroup analysis, but no significant gender-prognosis relationship was identified in the under-50 age group. High ISSs were associated with poorer outcomes across all age groups. Conclusion: In severe trauma, survival at 28 days was significantly lower in males. However, this trend was not observed in patients aged <50 years. Factors other than sex hormones may be responsible for differences in posttraumatic outcomes by gender.

Patient sex and outcomes in children with life-threatening hemorrhage

BACKGROUND

Recent data suggest female sex imparts a survival benefit after trauma in adults. The independent associations between patient sex and age with outcomes have not been examined in children with life-threatening hemorrhage (LTH) from all etiologies.

STUDY DESIGN AND METHODS

In a secondary analysis of a multicenter prospective observational study of children with LTH, Massive Transfusion in Children (MATIC), we analyzed if patient sex and age were associated with differences in severity of illness, therapies, and outcomes. Primary outcomes were 24 hour mortality and weight-adjusted transfusion volume during LTH. Kruskal-Wallis, chi-square testing, and multivariable linear regression were used for adjusted analyses.

RESULTS

Of 449 children, 45% were females and 55% were males. Females were more commonly younger, white, and with less trauma as the etiology of LTH compared to males. Markers of clinical severity were similar between groups, except injury severity score (ISS) was higher in females in the trauma subgroup. In terms of resuscitative practices, females received greater weight-adjusted total transfusion volumes compared to males (76 (40-150) mL/kg vs. 53 (24-100) mL/kg), as well as increased red blood cells (RBCs), plasma, and platelets compared to males. After adjustment for confounders, female sex and age 0-11 years were independently associated with increased transfusion volume during LTH. There were no differences in mortality or adverse outcomes according to patient sex.

CONCLUSION

Patient sex and age may impact factors associated with LTH and therapies received. Studies in developmental hemostasis are needed to determine the optimal transfusion strategy for LTH according to patient sex and age.

Sex dimorphisms in coagulation: Implications in trauma-induced coagulopathy and trauma resuscitation

Trauma-induced coagulopathy (TIC) is one of the leading causes of preventable death in injured patients. Consequently, it is imperative to understand the mechanisms underlying TIC and how to mitigate this mortality. An opportunity for advancement stems from the awareness that coagulation demonstrates a strong sex-dependent effect. Females exhibit a relative hypercoagulability compared to males, which persists after injury and confers improved outcomes. The mechanisms underlying sex dimorphisms in coagulation and its protective effect after injury have yet to be elucidated. This review explores sex dimorphisms in enzymatic hemostasis, fibrinogen, platelets, and fibrinolysis, with implications for resuscitation of patients with TIC.

Sex Dimorphism in Outcome of Trauma Patients Presenting with Severe Shock: A Multicenter Cohort Study

Background: The objective of this study was to determine the association between sex and outcome among severely injured patients who were admitted in severe shock. Methods: A retrospective multicenter study was performed in trauma patients (Injury Severity Score (ISS) ≥ 16) aged ≥ 16 presenting with severe shock (Shock Index > 1.3) over a 4-year period. To determine if sex was associated with mortality, Intensive Care Unit (ICU) admission, mechanical ventilation, blood transfusion and in-hospital complications, multivariable logistic regressions were performed. Results: In total, 189 patients were admitted to the Emergency Department in severe shock. Multivariable logistic regression analysis showed that female sex was independently associated with a decreased likelihood of acute kidney injury (OR 0.184; 95% CI 0.041-0.823; p = 0.041) compared to the male sex. A significant association between female sex and mortality, ICU admission, mechanical ventilation, other complications and packed red blood cells transfusion after admission could not be confirmed. Conclusion: Female trauma patients in severe shock were significantly less likely to develop AKI during hospital stay. These results could suggest that female trauma patients may manifest a better-preserved physiologic response to severe shock when compared to their male counterparts. Prospective studies with a larger study population are warranted.

The outcome of severely injured patients following traumatic brain injury is affected by gender—A retrospective, multicenter, matched-pair analysis utilizing data of the TraumaRegister DGU®

Introduction

Traumatic brain injury (TBI) causes a major health-concern globally. Gender-dependent differences in mortality outcome after TBI have been controversially discussed.

Materials and methods

We conducted a retrospective, multicenter, matched-pair analysis using data collected by the TraumaRegister DGU® of the German Trauma Society between 2009 and 2020. All patients after severe trauma with the leading injury of TBI (AIS ≥ 3), above 18 years of age were included. Thereby, 42,034 cases were identified. We used 12 different matching criteria to ensure highly accurate matching and were able to match 11,738 pairs of one female and one male patient.

Results

Average age at injury was 67.5 ± 19.6 years in women and 66.7 ± 19.1 years in men. Mean Injury Severity Score (ISS) was 21.3 ± 8.1 in women and 21.6 ± 8.2 in men. While women were more likely to die within the first week after trauma, the mortality was significantly higher in men overall (30.8 vs. 29.2%, p &lt; 0.002). Women were less likely to suffer from multi organ failure (MOF) (27.5 vs. 33.0%) or sepsis (4.5 vs. 7.1%). When comparing younger (≤ 45-years) and older (&gt; 45 years) patients, overall mortality was lower in men (13.1% men vs. 13.4% women) in the younger age group, but in the older group mortality was lower in women (33.8% men vs. 31.8% women).

Discussion

Gender-specific differences in the clinical outcome of severely injured patients with leading TBI could be detected. While women are overall characterized by an advantage in survival, this feature is not equally reproducible in premenopausal women. Therefore, the exact pathophysiological reasons for the described survival advantages of women will have to be explored in further prospective clinical studies.

INTERACTIONS BETWEEN BIOLOGICAL SEX AND THE X-LINKED VARIANT IRAK1 HAPLOTYPE IN MODULATING CLINICAL OUTCOME AND CELLULAR PHENOTYPES AFTER TRAUMA

ABSTRACT

Sex-related outcome differences in trauma remain controversial. The mechanisms causing sex-biased outcomes are likely to have hormonal and genetic components, in which X-linked genetic polymorphisms may play distinct roles because of X-linked inheritance, hemizygosity in males, and X chromosome mosaicism in females. The study aimed to elucidate the contribution of biological sex and the common X-linked IRAK1 haplotype to posttrauma clinical complications, inflammatory cytokine and chemokine production, and polymorphonuclear cell and monocyte activation. Postinjury clinical outcome was tested in 1507 trauma patients (1,110 males, 397 females) after stratification by sex or the variant IRAK1 haplotype. Males showed a three- to fivefold greater frequency of posttrauma sepsis, but similar mortality compared to females. Stratification by the variant IRAK1 haplotype revealed increased pneumonia and urinary tract infection in Wild type (WT) versus variant IRAK1 males, whereas increased respiratory failures in variant versus WT females. Cytokine/chemokine profiles were tested in whole blood from a subset of patients (n = 81) and healthy controls (n = 51), which indicated sex-related differences in ex vivo lipopolysaccharide responsiveness manifesting in a 1.5- to 2-fold increased production rate of tumor necrosis factor α, interleukin-1β (IL-1β), IL-10, Macrophage Inflammatory Protein-1 Alpha, and MIP1β in WT male compared to WT female trauma patients. Variant IRAK1 decreased IL-6, IL-8, and interferon gamma-induced protein 10 production in male trauma subjects compared to WT, whereas cytokine/chemokine responses were similar in variant IRAK1 and WT female trauma subjects. Trauma-induced and lipopolysaccharide-stimulated polymorphonuclear cell and monocyte activation determined by using a set of cluster of differentiation markers and flow cytometry were not influenced by sex or variant IRAK1. These findings suggest that variant IRAK1 is a potential contributor to sex-based outcome differences, but its immunomodulatory impacts are modulated by biological sex.

Thromboelastography-Based Evaluation of Gender-Associated Hypercoagulability

BACKGROUND

Age, race, and gender differences in coagulation status of healthy volunteers have been reported in previous case series; however, rigorous multivariate analysis adjusting for these factors is lacking. We aimed to investigate the effects of age, race, and gender on baseline coagulation status in healthy volunteers.

METHODS

Thirty healthy volunteer controls with no history of bleeding or thrombotic events and no previous anticoagulant or antiplatelet use were recruited. Citrated and heparinized blood samples were drawn, and kaolin and platelet-mapping thromboelastography (TEG) assays performed.

RESULTS

Thirty participants had a mean age of 37, mean body mass index of 29 kg/m², and were 47% African-American and 70% female. Women were significantly older than men (40 ± 11 y vs 28 ± 7 y, P = .002); there were no significant differences in demographics by race. Multivariate analysis of variance for the effect of age, race, and gender across TEG parameters yielded evidence for gender differences in hypercoagulability (Pillai's trace P = .02), which appear to be driven by differences in K-time, alpha angle, maximal amplitude, and G parameter. Women were hypercoagulable compared to men, as manifested by shorter K-time, steeper alpha angle, higher maximal amplitude, and larger G parameter.

DISCUSSION

Women at baseline have relatively hypercoagulable fibrin deposition kinetics, platelet contributions to clot formation, and overall clot strength compared to men, even when adjusted for age and race. Additional research is needed to specifically detail the key patient-level factors, clinical implications, and opportunities for tailored therapy related to gender-associated hypercoagulability.

State-of-the-Art Review: Sex Hormone Therapy in Trauma-Hemorrhage

ABSTRACT

Trauma-hemorrhage is the leading cause of prehospital and early in-hospital deaths, while also significantly contributing to the later development of multisystem organ dysfunction/failure and sepsis. Common and advanced resuscitative methods would potentially demonstrate benefits in the prehospital setting; however, they face a variety of barriers to application and implementation. Thus, a dialogue around a novel adjunct has arisen, sex hormone therapy. Proposed candidates include estradiol and its derivatives, metoclopramide hydrochloride/prolactin, dehydroepiandrosterone, and flutamide; with each having demonstrated a range of salutary effects in several animal model studies. Several retrospective analyses have observed a gender-based dimorphism in mortality following trauma-hemorrhage, thus suggesting that estrogens contribute to this pattern. Trauma-hemorrhage animal models have shown estrogens offer protective effects to the cardiovascular, pulmonary, hepatic, gastrointestinal, and immune systems. Additionally, a series of survival studies utilizing 17α-ethinylestradiol-3-sulfate, a potent, water-soluble synthetic estrogen, have demonstrated a significant survival benefit and beneficial effects on cardiovascular function. This review presents the findings of retrospective clinical studies, preclinical animal studies, and discusses how and why 17α-ethinylestradiol-3-sulfate should be considered for investigation within a prospective clinical trial.

An estrogen (17α-ethinyl estradiol-3-sulfate) reduces mortality in a swine model of multiple injuries and hemorrhagic shock

BACKGROUND

Although 17α-ethinyl estradiol-3-sulfate (EES) reduces mortality in animal models of controlled hemorrhage, its role in a clinically relevant injury model is unknown. We assessed the impact of EES in a swine model of multiple injuries and hemorrhage.

METHODS

The study was performed under Good Laboratory Practice, with 30 male uncastrated swine (25-50 kg) subjected to tibial fracture, pulmonary contusion, and 30% controlled hemorrhage for an hour. Animals were randomized to one of five EES doses: 0 (control), 0.3, 1, 3, and 5 mg/kg, administered postinjury. Subjects received no resuscitation and were observed for 6 hours or until death. Survival data were analyzed using Cox-proportional hazard regression. Left ventricular pressure-volume loops were used to derive preload recruitable stroke work as a measure of cardiac inotropy. Immediate postinjury preload recruitable stroke work values were compared with values at 1 hour post-drug administration.

RESULTS

Six-hour survival for the 0, 0.3, 1, 3, and 5 mg/kg groups was 0%, 50%, 33.3%, 16.7%, and 0%, respectively. Following Cox regression, the hazard (95% confidence interval) of death was significantly reduced in the 0.3 (0.22 [0.05-0.93]) and 1 (0.24 [0.06-0.89]) mg/kg groups but not the 3 (0.49 [0.15-1.64]) and 5 (0.46 [0.14-1.47]) mg/kg groups. Mean survival time was significantly extended in the 1 mg/kg group (246 minutes) versus the 0 mg/kg group (96 minutes) (p = 0.04, t test). At 1 hour post-drug administration, inotropy was significantly higher than postinjury values in the 0.3 and 1 mg/kg groups (p = 0.003 and p < 0.001, respectively). Inotropy was unchanged in the 3 and 5 mg/kg groups but significantly depressed in the control (p = 0.022).

CONCLUSION

Administration of EES even in the absence of fluid resuscitation reduces mortality and improves cardiac inotropy in a clinically relevant swine model of multiple injuries and hemorrhage. These findings support the need for a clinical trial in human trauma patients.

Genetic Modulators of Traumatic Brain Injury in Animal Models and the Impact of Sex-Dependent Effects

Traumatic brain injury (TBI) is a major health problem causing disability and death worldwide. There is no effective treatment, due in part to the complexity of the injury pathology and factors affecting its outcome. The extent of brain injury depends on the type of insult, age, sex, lifestyle, genetic risk factors, socioeconomic status, other co-injuries, and underlying health problems. This review discusses the genes that have been directly tested in TBI models, and whether their effects are known to be sex-dependent. Sex differences can affect the incidence, symptom onset, pathology, and clinical outcomes following injury. Adult males are more susceptible at the acute phase and females show greater injury in the chronic phase. TBI is not restricted to a single sex; despite variations in the degree of symptom onset and severity, it is important to consider both female and male animals in TBI pre-clinical research studies.

Hypercoagulability in pregnant trauma patients

Circulating hormones affect coagulopathy in pregnancy and after trauma. The hemostatic profile of pregnant women after injury has not been characterized. We hypothesized that injured pregnant females would present with an initial thrombelastography (TEG) reflecting a more hypercoagulable profile and a higher incidence of venous thromboembolic events (VTE) when compared with non-pregnant females and males.

An Analysis of Outcomes and Interventions for Female Pediatric Casualties in Iraq and Afghanistan

BACKGROUND

Traumatic injuries were the most common reason for admission of pediatric patients to military hospitals during the recent wars in Iraq and Afghanistan. We compare survival and interventions between female and male pediatric casualties.

MATERIALS AND METHODS

This is a secondary analysis of a previously described dataset from the Department of Defense Trauma Registry. We requested pediatric encounters from January 2007 to January 2016 within Iraq and Afghanistan. We separated casualties by sex to compare injury and mortality patterns.

RESULTS

Our initial dataset included 3439 pediatric encounters-784 (22.8%) females and 2655 (77.2%) males. Females were less likely to sustain injuries by explosive (38.0% versus 44.5%) but more likely to sustain injuries via alternative mechanisms of injury (28.9% versus 21.5%). Both sexes had similar ISS (females median 10 [5-17], males 10 [4-17]). Fewer females underwent tourniquet application (4.2% versus 7.2%; all findings were significant). In unadjusted and adjusted regression analyses, females under age 8 had lower odds of survival to hospital discharge (OR 0.67, 95% CI 0.51-0.89) compared to males.

CONCLUSIONS

Among pediatric patients treated by U.S. medical personnel in Iraq and Afghanistan, females had a lower survival to hospital discharge despite similar severity of injury. Further studies are necessary to elucidate causes for this finding.

Sex differences in long-term outcomes after traumatic injury: A mediation analysis

BACKGROUND

We sought to examine the association and potential mediators between sex and long-term trauma outcomes.

METHODS

Moderately-to-severely injured patients admitted to 3 level-1 trauma centers were contacted between 6 and 12-months post-injury to assess for functional limitations, use of pain medications, and posttraumatic stress disorder (PTSD). Multivariable adjusted regression analyses were used to compare long-term outcomes by sex. Potential mediators of the relationship between sex and outcomes was explored using mediation analysis.

RESULTS

2607 patients were followed, of which 45% were female. Compared to male, female patients were more likely to have functional limitations (OR: 1.45; 95% CI: 1.31-1.60), take pain medications (OR: 1.17; 95% CI: 1.02-1.38), and screen positive for PTSD (OR: 1.60; 95% CI: 1.46-1.76) post-injury. Age, extremity injury, previous psychiatric illness, and pre-injury unemployment, partially mediated the effect of female sex on long-term outcomes.

CONCLUSIONS

There are significant sex differences in long-term trauma outcomes, which are partially driven by patient and injury-related factors.

Gender Disparities in Surgical Treatment of Axis Fractures in Older Adults

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Gender appears to play in important role in surgical outcomes following acute cervical spine trauma, with current literature suggesting males have a significantly higher mortality following spine surgery. However, no well-adjusted population-based studies of gender disparities in incidence and outcomes of spine surgery following acute traumatic axis injuries exist to our knowledge. We hypothesized that females would receive surgery less often than males, but males would have a higher 1-year mortality following isolated traumatic axis fractures.

METHODS

We performed a retrospective cohort study using Medicare claims data that identified US citizens aged 65 and older with ICD-9 (International Classification of Diseases, Ninth Revision) code diagnosis corresponding to isolated acute traumatic axis fracture between 2007 and 2014. Our primary outcome was defined as cumulative incidence of surgical treatment, and our secondary outcome was 1-year mortality. Propensity weighted analysis was performed to balance covariates between genders. Our institutional review board approved the study (IRB #16-0533).

RESULTS

There was no difference in incidence of surgery between males and females following acute isolated traumatic axis fractures (7.4 and 7.5 per 100 fractures, respectively). Males had significantly higher 1-year weighted mortality overall (41.7 and 28.9 per 100 fractures, respectively, P < .001).

CONCLUSION

Our well-adjusted data suggest there was no significant gender disparity in incidence of surgical treatment over the study period. The data also support previous observations that males have worse outcomes in comparison to females in the setting of axis fractures and spinal trauma regardless of surgical intervention.

Role of gender in the survival outcome of acute phase of major trauma: A nationwide, population-based study

BACKGROUND

Animal models of trauma have shown that females have better posttraumatic survival; however, results of previous studies on the influence of gender on major trauma patients have been controversial. This study aimed to evaluate the association between gender and survival in major trauma patients.

METHODS

We retrospectively analyzed patients registered in Taiwan's National Health Insurance Research Database between 2008 and 2012 with the diagnosis codes 800-939 and 950-957 (International Classification of Diseases, ninth revision, clinical modification). Data on gender, age, catastrophic illness, and new injury severity score (NISS) ≥16 were collected for comparing patients' mortality after trauma. Propensity score matching (PSM) was performed to eliminate dissimilarities in age, comorbidities, NISS, and primary traumatic regions between the genders.

RESULTS

Among 10 012 major trauma patients included in the study cohort, 28.8% (n = 2880) were women. The PSM patient group consisted of 50% (2876 of 5752) women. Women had a higher 30-day (15.4% of women vs 13.8% of men; p < 0.05) and hospital (16.1% of women vs 14.5% of men; p < 0.05) mortality and lower incidence rates of acute respiratory dysfunction (62.5% of women vs 65.9% of men; p < 0.005) and acute hepatic dysfunction (0.8% of women vs 2.1% of men; p < 0.001). However, the analysis of PSM patient groups showed lower mortality rates in women with moderate trauma (NISS 16-24) in the acute phase within three days (1.4% of women vs 2.7% of men, p = 0.03). Analysis of patients with an NISS of 16-24 who died within three days showed a higher NISS in women than in men (19.7 ± 2.3 vs 18.0 ±1.9, respectively, p <0.05).

CONCLUSION

There is no gender difference in 30-day or hospital mortality among major trauma patients. However, women admitted for moderate major trauma had higher survival within three days of major trauma.

Why do some trauma patients die while others survive? A matched-pair analysis based on data from Trauma Register DGU®

PURPOSE

The mortality rate for severely injured patients with the injury severity score (ISS) ≥16 has decreased in Germany. There is robust evidence that mortality is influenced not only by the acute trauma itself but also by physical health, age and sex. The aim of this study was to identify other possible influences on the mortality of severely injured patients.

METHODS

In a matched-pair analysis of data from Trauma Register DGU®, non-surviving patients from Germany between 2009 and 2014 with an ISS≥16 were compared with surviving matching partners. Matching was performed on the basis of age, sex, physical health, injury pattern, trauma mechanism, conscious state at the scene of the accident based on the Glasgow coma scale, and the presence of shock on arrival at the emergency room.

RESULTS

We matched two homogeneous groups, each of which consisted of 657 patients (535 male, average age 37 years). There was no significant difference in the vital parameters at the scene of the accident, the length of the pre-hospital phase, the type of transport (ground or air), pre-hospital fluid management and amounts, ISS, initial care level, the length of the emergency room stay, the care received at night or from on-call personnel during the weekend, the use of abdominal sonographic imaging, the type of X-ray imaging used, and the percentage of patients who developed sepsis. We found a significant difference in the new injury severity score, the frequency of multi-organ failure, hemoglobine at admission, base excess and international normalized ratio in the emergency room, the type of accident (fall or road traffic accident), the pre-hospital intubation rate, reanimation, in-hospital fluid management, the frequency of transfusion, tomography (whole-body computed tomography), and the necessity of emergency intervention.

CONCLUSION

Previously postulated factors such as the level of care and the length of the emergency room stay did not appear to have a significant influence in this study. Further studies should be conducted to analyse the identified factors with a view to optimising the treatment of severely injured patients. Our study shows that there are significant factors that can predict or influence the mortality of severely injured patients.

Neuroendocrine Modulation of the Immune Response after Trauma and Sepsis: Does It Influence Outcome?

Although the treatment of multiple-injured patients has been improved during the last decades, sepsis and multiple organ failure (MOF) still remain the major cause of death. Following trauma, profound alterations of a large number of physiological systems can be observed that may potentially contribute to the development of sepsis and MOF. This includes alterations of the neuroendocrine and the immune system. A large number of studies focused on posttraumatic changes of the immune system, but the cause of posttraumatic immune disturbance remains to be established. However, an increasing number of data indicate that the bidirectional interaction between the neuroendocrine and the immune system may be an important mechanism involved in the development of sepsis and MOF. The aim of this article is to highlight the current knowledge of the neuroendocrine modulation of the immune system during trauma and sepsis.

Factors Associated With Long-term Outcomes After Injury: Results of the Functional Outcomes and Recovery After Trauma Emergencies (FORTE) Multicenter Cohort Study

OBJECTIVE

The aim of this study was to determine factors associated with patient-reported outcomes, 6 to 12 months after moderate to severe injury.

SUMMARY OF BACKGROUND DATA

Due to limitations of trauma registries, we have an incomplete understanding of factors that impact long-term patient-reported outcomes after injury. As 96% of patients survive their injuries, several entities including the National Academies of Science, Engineering and Medicine have called for a mechanism to routinely follow trauma patients and determine factors associated with survival, patient-reported outcomes, and reintegration into society after trauma.

METHODS

Over 30 months, major trauma patients [Injury Severity Score (ISS) ≥9] admitted to 3 Level-I trauma centers in Boston were assessed via telephone between 6 and 12 months after injury. Outcome measures evaluated long-term functional, physical, and mental-health outcomes. Multiple regression models were utilized to identify patient and injury factors associated with outcomes.

RESULTS

We successfully followed 1736 patients (65% of patients contacted). More than half (62%) reported current physical limitations, 37% needed help for at least 1 activity of daily living, 20% screened positive for posttraumatic stress disorder (PTSD), all SF-12 physical health subdomain scores were significantly below US norms, and 41% of patients who were working previously were unable to return to work. Age, sex, and education were associated with long-term outcomes, while almost none of the traditional measures of injury severity were.

CONCLUSION

The long-term sequelae of trauma are more significant than previously expected. Collection of postdischarge outcomes identified patient factors, such as female sex and low education, associated with worse recovery. This suggests that social support systems are potentially at the core of recovery rather than traditional measures of injury severity.

Sex dimorphism in pediatric burn mortality in Malawi: A propensity matched analysis

INTRODUCTION

There is increasing evidence that sex differences may influence pathophysiology after thermal injury and affect clinical outcomes. This study aimed to assess the relationships between sex, thermal injury, and inpatient mortality in a pediatric burn cohort in a resource-limited setting.

METHOD

This is a retrospective analysis of data collected from the Kamuzu Central Hospital Burns Unit, in Lilongwe, Malawi, from May 2011 to December 2019 on all pediatric patients (≤12 years). We performed a bivariate analysis by sex comparing demographics, burn characteristics, surgical intervention, and mortality. Standardized estimates were adjusted using the inverse probability of treatment weights to account for confounding. Following weighting, odds of mortality based on sex were obtained via logistic regression modeling.

RESULTS

A total of 1904 children were admitted with a male preponderance (n = 1065, 55.9 %). Overall, the median age was 3 years (IQR1-4). Females had a higher percent total body surface area (%TBSA) burn than males, 15 % vs. 13 % (p = 0.03), respectively. Flame burns were more frequent in females compared to males, 32 % and 23 %, respectively (p < 0.001). There were higher rates of surgical intervention in females than males (20.9 % vs. 16.7 %, p = 0.02). The propensity score weighted logistic regression predicting mortality revealed no difference in the odds of mortality based on sex (OR 1.12, 95 % CI 0.82-1.52, p = 0.5).

CONCLUSION

We show males are just as likely to die from burns compared to females with similar injuries in this propensity-matched analysis. A lack of difference in mortality may be attributable to the similarities in the hormonal profile in the prepubescent child.

Temporal progression of gene regulation of peripheral white blood cells explains gender dimorphism of critically ill patients after trauma

BACKGROUND

The immune response of the critically ill after severe trauma is sex-specific and may explain the different progression of the disease. This may be explained by a different gene regulatory program of their peripheral immune cells. We investigated the progression of the transcription profiles of peripheral immune cells of the patients to elucidate their distinct physiological response and clinical course.

METHODS

We compared transcription profiles of whole blood of male and female patients from a larger longitudinal study of critically ill patients after trauma. We developed a statistical analysis pipeline that synchronized the time lapse of the profiles based on the temporal severity score of each patient.

RESULTS

This enabled to categorize the temporal progression of the disease into two pre-acute, an acute and two post-acute phases. Comparing gene regulation of male and female patients at each phase, we identified distinctively regulated molecular processes mainly in the immune response, but also in the regulation of metabolism allowing to cluster these discriminative gene sets into sets of highly related cellular processes. Compared to male patients and healthy controls, female patients showed upregulation of gene sets of innate immunity in the early phase, upregulation of wound healing processes during the acute phase and upregulation of adaptive immunity in the late phase indicating early recovery. In turn, during the pre-acute and acute phase, male patients showed less suppression of gene sets coding for enzymes of energy metabolism and anabolism, most prominently the tricarboxylic acid cycle and β-oxidation, and cellular maintenance, such as cell cycle, DNA replication and damage response, and RNA metabolism.

CONCLUSIONS

A stronger innate immune response at the very early phase of the disease may support early clearance of the pathogen and its associated molecular patterns. Upregulation of wound healing processes may explain reduced multiple organ failure during the acute phase. Down regulated energy metabolism during the acute phase may make female patients less susceptible to oxidative stress, the upregulated adaptive immune system reflects an earlier recovery and rebuilding of the adaptive immune system that may protect them from secondary infections. Follow up studies need to be performed confirming these observations experimentally.

Sex-based differences in transfusion need after severe injury: Findings of the PROPPR study

BACKGROUND

Women are underrepresented in trauma research, and aggregated results of clinical trials may mask effects that differ by sex. It is unclear whether women respond differently to severe hemorrhage compared with men. We sought to evaluate sex-based differences in outcomes after severe trauma with hemorrhage.

METHODS

We performed a secondary analysis of the Pragmatic Randomized Optimal Platelet and Plasma Ratios trial. Trauma patients predicted to require massive transfusion were randomized to a 1:1:1 vs 1:1:2 plasma to platelet to red blood cell transfusion ratio. Analysis was performed according to sex, controlling for clinical characteristics and transfusion arm.

RESULTS

A total of 134 women and 546 men were analyzed. In multivariable analysis, there was no difference in mortality at 24 hours (hazard ratio for women 0.64, 95% confidence interval 0.34-1.23, P = .18) or in time to hemostasis (hazard ratio 1.10, 95% confidence interval 0.84-1.42, P = .49) by sex. We observed no difference between sexes in volume of blood products transfused during active hemorrhage. However, after anatomic hemostasis, women received lower volumes of all products, with a 38% reduction in fresh frozen plasma (mean ratio 0.62 (95% confidence interval 0.43-0.89, P = .01), 49% reduction in platelets (mean ratio 0.51, 95% confidence interval 0.33-0.79, P < .01) and 49% reduction in volume of red blood cells (mean ratio 0.51, 95% confidence interval 0.33-0.79, P < .01).

CONCLUSION

Mortality and time to hemostasis of trauma patients with hemorrhage did not differ by sex. Although there was no difference in transfusion requirement during active hemorrhage, once hemostasis was achieved, women received fewer units of all blood products than men. Further research is required to determine whether women exhibit differences in coagulation during and after severe traumatic hemorrhage.

Is there an association between female gender and outcome in severe trauma? A multi-center analysis in the Netherlands

INTRODUCTION

Little evidence suggest that female gender is associated with a lower risk of mortality in severely injured patients, especially in premenopausal women. Previous clinical studies have shown contradictory results regarding protective effects of gender on outcome after severe trauma. The objective of this study was to determine the association between gender and outcome (mortality and Intensive Care Unit (ICU) admission) among severely injured patients in the Netherlands.

METHODS

A retrospective multicentre study was performed including all polytrauma patients (Injury Severity Score (ISS) ≥16) admitted to the ED of three level 1 trauma centres, between January 1st, 2006 and December 31st, 2014. Data on age, gender, mechanism of injury, ISS, Abbreviated Injury Scale (AIS), prehospital intubation, Revised Trauma Score (RTS), systolic blood pressure (SBP) and Glasgow Coma Scale (GCS) upon admission at the Emergency Department was collected from three Regional Trauma Registries. To determine whether gender was an independent predictor of mortality and ICU admission, logistic regression analysis was performed.

RESULTS

Among 6865 trauma patients, male patients had a significantly higher ISS compared to female patients (26.3 ± 10.2 vs 25.3 ± 9.7, P = < 0.0001). Blunt trauma was significantly more common in the female group (95.2% vs 92.3%, P = < 0.0001). Males aged 16- to 44-years had a significant higher in-hospital mortality rate (10.4% vs 13.4%, P = 0.046). ICU admission rate was significantly lower in females (49.3% vs 54.5%, P = < 0.0001). In the overall group, logistic regression did not show gender as an independent predictor for in-hospital mortality (OR 1.020 (95% CI 0.865-1.204), P = 0.811) or mortality within 24 h (OR 1.049 (95% CI 0.829-1.327), P = 0.693). However, male gender was associated with an increased likelihood for ICU admission in the overall group (OR 1.205 (95% CI 1.046-1.388), P = 0.010).

CONCLUSION

The current study shows that in this population of severely injured patients, female sex is associated with a lower in-hospital mortality rate among those aged 16- to 44-years. Furthermore, female sex is independently associated with an overall decreased likelihood for ICU admission. More research is needed to examine the physiologic background of this protective effect of female sex in severe trauma.

Trauma Resuscitation Consideration: Sex Matters

BACKGROUND

Sex dimorphisms in coagulation have been recognized, but whole blood assessment of these dimorphisms and their relationship to outcomes in trauma have not been investigated. This study characterizes the viscoelastic hemostatic profile of severely injured patients by sex, and examines how sex-specific coagulation differences affect clinical outcomes, specifically, massive transfusion (MT) and death. We hypothesized that severely injured females are more hypercoagulable and therefore, have lower rates of MT and mortality.

STUDY DESIGN

Hemostatic profiles and clinical outcomes from all trauma activation patients from 2 level I trauma centers were examined, with sex as an experimental variable. As part of a prospective study, whole blood was collected and thrombelastography (TEG) was performed. Coagulation profiles were compared between sexes, and association with MT and mortality were examined. Poisson regression with robust standard errors was performed.

RESULTS

Overall, 464 patients (23% female) were included. By TEG, females had a more hypercoagulable profile, with a higher angle (clot propagation) and maximum amplitude (MA, clot strength). Females were less likely to present with hyperfibrinolysis or prolonged activating clotting time than males. In the setting of depressed clot strength (abnormal MA), female sex conferred a survival benefit, and hyperfibrinolysis was associated with higher case-fatality rate in males.

CONCLUSIONS

Severely injured females have a more hypercoagulable profile than males. This hypercoagulable status conferred a protective effect against mortality in the setting of diminished clot strength. The mechanism behind these dimorphisms needs to be elucidated and may have treatment implications for sex-specific trauma resuscitation.

Gender Disparities in Trauma Care: How Sex Determines Treatment, Behavior, and Outcome

Trauma data bank and other research reveal sex disparities in trauma care. Risk-taking behaviors leading to traumatic injury have been associated with sex, menstrual cycle timing, and cortisol levels. Trauma patient treatment stratified by sex reveals differences in access to services at trauma centers as well as specific treatments, such as venous thromboembolism prophylaxis and massive transfusion component ratios. Trauma patient outcomes, such as in-hospital mortality, multiple organ failure, pneumonia, and sepsis are associated with sex disparities in the general trauma patient. Outcome after general trauma and specifically traumatic brain injury show mixed results with respect to sex disparity.

Missing data in trauma registries: A systematic review

BACKGROUND

Trauma registries play an integral role in trauma systems but their valid use hinges on data quality. The aim of this study was to determine, among contemporary publications using trauma registry data, the level of reporting of data completeness and the methods used to deal with missing data.

METHODS

A systematic review was conducted of all trauma registry-based manuscripts published from 01 January 2015 to current date (17 March 2017). Studies were identified by searching MEDLINE, EMBASE, and CINAHL using relevant subject headings and keywords. Included manuscripts were evaluated based on previously published recommendations regarding the reporting and discussion of missing data. Manuscripts were graded on their degree of characterization of such observations. In addition, the methods used to manage missing data were examined.

RESULTS

There were 539 manuscripts that met inclusion criteria. Among these, 208 (38.6%) manuscripts did not mention data completeness and 88 (16.3%) mentioned missing data but did not quantify the extent. Only a handful (n = 26; 4.8%) quantified the 'missingness' of all variables. Most articles (n = 477; 88.5%) contained no details such as a comparison between patient characteristics in cohorts with and without missing data. Of the 331 articles which made at least some mention of data completeness, the method of managing missing data was unknown in 34 (10.3%). When method(s) to handle missing data were identified, 234 (78.8%) manuscripts used complete case analysis only, 18 (6.1%) used multiple imputation only and 34 (11.4%) used a combination of these.

CONCLUSION

Most manuscripts using trauma registry data did not quantify the extent of missing data for any variables and contained minimal discussion regarding missingness. Out of the studies which identified a method of managing missing data, most used complete case analysis, a method that may bias results. The lack of standardization in the reporting and management of missing data questions the validity of conclusions from research based on trauma registry data.

Contemporary Patterns of Multiple Organ Dysfunction in Trauma

BACKGROUND

Multiple organ dysfunction syndrome (MODS) is associated with poor outcomes for trauma patients. Different forms of MODS may exist and have different consequences. The ability to distinguish them clinically may have implications for prognosis and treatment. We wished to study whether prolonged MODS (PRMODS) could be observed as a distinct clinical entity to early resolving MODS (ERMODS) in critically injured patients.

METHODS

Adult major trauma patients recruited to a prospective observational study at a single major trauma center were eligible for inclusion. MODS was defined as Sequential Organ Failure Assessment (SOFA) score >5; and PRMODS as lasting >7 days. Time to recovery (TTR) was calculated as the number of days before the SOFA fell below the MODS threshold (≤5).

RESULTS

Five hundred ninety-five patients were enrolled of whom 285 developed ERMODS (48%) and 184 (31%) PRMODS. Organ dysfunction was more severe and protracted in PRMODS, especially in patients without brain injury (mean SOFA 11 vs. 6, Day 2, P < 0.001; TTR 17 vs. 3 days, P < 0.001). PRMODS exhibited higher rates of hepatic and renal dysfunction (84% vs. 56%; and 78% vs. 47%, P≤0.001). Patterns of recovery were distinct in hepatic, renal, and neurological systems (TTR 15 vs. 4; 20 vs. 3; and 28 vs. 7 days, P < 0.01). PRMODS was associated with higher infection and mortality rates (91% vs. 41%; and 22% vs. 7%, P < 0.001).

CONCLUSION

PRMODS appears common, a distinct clinical entity, and associated with worse patient outcomes. PRMODS may represent an important endpoint for studies evaluating outcomes following trauma.

Guiding Management in Severe Trauma: Reviewing Factors Predicting Outcome in Vastly Injured Patients

Trauma is one of the leading causes of death worldwide, with road traffic collisions, suicides, and homicides accounting for the majority of injury-related deaths. Since trauma mainly affects young age groups, it is recognized as a serious social and economic threat, as annually, almost 16,000 posttrauma individuals are expected to lose their lives and many more to end up disabled. The purpose of this research is to summarize current knowledge on factors predicting outcome - specifically mortality risk - in severely injured patients. Development of this review was mainly based on the systematic search of PubMed medical library, Cochrane database, and advanced trauma life support Guiding Manuals. The research was based on publications between 1994 and 2016. Although hypovolemic, obstructive, cardiogenic, and septic shock can all be seen in multi-trauma patients, hemorrhage-induced shock is by far the most common cause of shock. In this review, we summarize current knowledge on factors predicting outcome - more specifically mortality risk - in severely injured patients. The main mortality-predicting factors in trauma patients are those associated with basic human physiology and tissue perfusion status, coagulation adequacy, and resuscitation requirements. On the contrary, advanced age and the presence of comorbidities predispose patients to a poor outcome because of the loss of physiological reserves. Trauma resuscitation teams considering mortality prediction factors can not only guide resuscitation but also identify patients with high mortality risk who were previously considered less severely injured.

The influence of sex steroid hormones on the response to trauma and burn injury

Trauma and related sequelae result in disturbance of homeostatic mechanisms frequently leading to cellular dysfunction and ultimately organ and system failure. Regardless of the type and severity of injury, gender dimorphism in outcomes following trauma have been reported, with females having lower mortality than males, suggesting that sex steroid hormones (SSH) play an important role in the response of body systems to trauma. In addition, several clinical and experimental studies have demonstrated the effects of SSH on the clinical course and outcomes following injury. Animal studies have reported the ability of SSH to modulate immune, inflammatory, metabolic and organ responses following traumatic injury. This indicates that homeostatic mechanisms, via direct and indirect pathways, can be maintained by SSH at local and systemic levels and hence result in more favourable prognosis. Here, we discuss the role and mechanisms by which SSH modulates the response of the body to injury by maintaining various processes and organ functions. Such properties of sex hormones represent potential novel therapeutic strategies and further our understanding of current therapies used following injury such as oxandrolone in burn-injured patients.

Sex-based differences in the genomic response, innate immunity, organ dysfunction, and clinical outcomes after severe blunt traumatic injury and hemorrhagic shock

INTRODUCTION

The effect of sex on posttraumatic pathophysiology and outcomes after severe traumatic injury remains debated. We sought to determine the relationship of sex to the genomic and inflammatory responses, and clinical outcomes after hemorrhagic shock.

METHODS

We analyzed blunt trauma patients in hemorrhagic shock from a prospective multi-institutional cohort study to assess for sex-based differences in the genomic response and clinical outcomes. Serially drawn blood samples were analyzed to evaluate peripheral leukocyte genomewide expression and circulating inflammatory mediators at intervals between 0.5 and 28 days after injury. Multivariate logistic regression models were developed to assess the effect of sex on outcomes after controlling for age, injury and shock severity, blood transfusion, and comorbidities.

RESULTS

The cohort consisted of 1,285 (67%) male and 643 (33%) female blunt trauma patients. Injury and shock severity were similar between the two groups. There were small but statistically significant differences between males and females regarding their age, body mass index, and 12-hour blood and crystalloid administration. Organ failure was more severe in males, with slower recovery (9.0 vs. 6.5 days) in males compared to females (p < 0.01). However, there were no differences between males and females in plasma levels of IL-6, IL-8, IL-10, IL-1β, tumor necrosis factor alpha, and monocyte chemoattractant protein 1. Multivariate analysis revealed that sex was not a significant independent risk factor for complicated recovery or 28-day mortality. Transcriptomic analysis revealed 333 genes with significant differential expression patterns between males and females (FDR, <0.001), including genes associated with general inflammation, innate immunity, cell adhesion, and cell signaling. None of the former genes were directly associated with sex hormones or X/Y chromosomes.

CONCLUSION

There are sex-specific differences in the leukocyte genomic response to severe injury that are associated with more robust and longer-duration organ dysfunction. However, these expression patterns do not seem to be associated with sex-linked genes or circulating cytokine level differences, and do not translate to worsened sex-specific organ failure outcomes or inpatient mortality.

LEVEL OF EVIDENCE

Prognostic/epidemiologic study, level III.

Systematic review of gender- dependent outcomes in sepsis

BACKGROUND

Men and women appear to exhibit different susceptibilities to sepsis and possibly divergent outcomes. However, the effect of sex and gender in critical illness outcomes is still controversial and the underlying mechanisms appear to be complex.

OBJECTIVES

We aimed to systematically review and synthesize evidence on the influence of sex on outcomes in critically ill adult patients with sepsis, as reported in published studies specifically including investigation of the effect of sex among their aims. Primary outcome measures include in-hospital mortality, intensive care unit (ICU) mortality and length of stay (LOS) in the ICU.

SEARCH STRATEGY

The review was based on focused literature searches (CINAHL, PUBMED, EMBASE and COCHRANE). Methodological quality was assessed through the STROBE checklist and the Cochrane Tool for Bias in Cohort Studies. Meta-analysis was performed using STATA. Published observational studies addressing outcomes of sepsis among their primary aims and having included gender comparisons among primary outcomes in critically ill adult patients were included.

RESULTS

A total of eight eligible studies were included. With the exception of mortality, it was not possible to perform meta-analysis for other outcomes. Included studies reported data on 25,619 patients with sepsis (14 309 male/11 310 female). There is a paucity of well-designed studies addressing the effect of sex on mortality among patients with sepsis, and absence of studies addressing the effects of sex on multiple organ dysfunction of non-infectious origin. There was significant heterogeneity among study estimates (p = 0·001; I² =78·1%).

CONCLUSIONS

Although results of data syntheses appear to point towards a small disadvantage for survival among women, our results suggest that data on the impact of sex on sepsis outcomes remain equivocal. Implications for future research include approaches to adjustment for confounders and prospective designs.

RELEVANCE TO CLINICAL PRACTICE

Clarifying sex-related differences in sepsis, if any, is crucial for informing evidence-based care.

Numbers of Severely Injured Patients in Germany. A Retrospective Analysis From the DGU (German Society for Trauma Surgery) Trauma Registry

BACKGROUND

Persons who sustain severe traumatic injury, i.e., those with an Injury Severity Score (ISS) of 16 or above, go on to suffer major physical, emotional, and socio-economic consequences. It is important to know the incidence of severe trauma so that these patients can be cared for optimally.

METHODS

Data from the year 2012 on severely injured persons with an ISS of 16 or above were obtained from the trauma registry of the German Society for Trauma Surgery (DGU) and analyzed. Further information was obtained from the database of the DGU trauma network. The annual incidence of severe trauma was estimated from these data in three different ways.

RESULTS

An extrapolation of hospital-based data to the German population yielded a figure of 16 742 severely injured persons per year. A population-based estimate from the German federal state of Bavaria yielded a figure of 16 514/year, while an area-based extrapolation using data from 17 established networks yielded a figure of 16 554/year. We added 10% to each of these figures as a correction for assumed underreporting. We conclude that the number of persons who sustained a severe traumatic injury in Germany in 2012 lay between 18 209 (95% confidence interval [CI]: 17 751-18 646) and 18 416 (95% CI: 18 156-18 695). This corresponds to an incidence of 0.02% per year.

CONCLUSION

Data from a prospectively maintained nationwide trauma registry were used for the first time to calculate the annual incidence of severe traumatic injury in Germany: the expected number of severely injured persons per year is 18 200-18 400. Previous extrapolations yielded values in the range of 32 500-35 300. A high variability of documentation practices among supraregional trauma centers may have distorted the estimate, along with other factors. The figures were not normalized for age or sex.

Influence of gender on systemic IL-6 levels, complication rates and outcome after major trauma

BACKGROUND

While female gender was associated with lower rates of systemic inflammatory response syndrome (SIRS), sepsis and single and/or multiple organ failure (MOF), contradictory data suggest no correlation between gender and complication rates and/or outcome in trauma patients (TP). Here, we analyzed the gender influence on systemic interleukin (IL)-6 levels and outcome in TP.

PATIENTS/METHODS

343 TP with injury severity scores (ISS) ≥16 were included upon admittance to the emergency department (ED) and grouped to male (n=257) vs. female (n=86). Injury severity, vital signs, physiological parameters, length of intensive care unit (ICU) and in-hospital stay, outcome parameters including SIRS, sepsis, respiratory complications, single- and/or MOF and in-hospital mortality were analyzed. Systemic IL-6 levels during the first 10 post-injury days were determined daily.

RESULTS

Age (45.0±1.0 vs. 48.2±2.1) and ISS (27.1±0.8 vs. 24.7±1.2) were comparable between both groups. Abbreviated Injury Scale (AIS) ≥3 of chest and abdominal body regions were significantly higher in male TP (chest:51.02% vs. 36.05%, abdomen:19.84% vs. 10.47%, p<0.05). IL-6 was significantly increased in male TP on post-injury days 1 and 2 (d1:363.9±72.58 vs. 163.7±25.98; d2:194.3±31.38 vs. 114.3±17.81pg/ml, p<0.05). Multivariate analysis excluded an association of increased chest or abdominal injury occurrence with IL-6 levels. Female vs. male TP had significantly lower SIRS and sepsis occurrence (SIRS:40.70% vs. 53.31%, sepsis:6.98% vs. 19.46%, p<0.05). There were no gender-based differences regarding ICU or in-hospital stay, single and/or MOF and respiratory complications.

CONCLUSIONS

Taken together, higher systemic IL-6 levels after trauma are associated with enhanced susceptibility for SIRS and sepsis in male patients.

Does Patient Sex Affect the Rate of Mortality and Complications After Spine Surgery? A Systematic Review

BACKGROUND

Available studies disagree regarding the influence of patient sex on mortality and complications after spine surgery. We sought to conduct a systematic review and pool the results of existing research to better understand this issue.

QUESTIONS/PURPOSES

We performed a systematic review to address two questions: (1) Does sex (male versus female) influence mortality after spine surgery? (2) Does sex impact the development of postoperative complications after spine surgery?

METHODS

This systematic review was performed through a query of PubMed using a structured search algorithm. Additional queries of Embase, SCOPUS, Web of Science, and the tables of contents of orthopaedic and neurosurgical journals were also conducted using search terms such as "sex factors", "male or female", "risk factors", and "spine surgery". Selected papers were independently abstracted by three of the authors (AJS, ENR, EIW) and pooling was performed. Our literature search returned 720 studies, of which 99 underwent full review. Of these, 50 were selected for final abstraction. The Cochrane Q test was used to assess study heterogeneity; significant study heterogeneity was present and so a random-effects model was used. A Harbord test was used to evaluate for the presence of publication bias; this analysis found no statistically significant evidence of publication bias.

RESULTS

Males were at increased odds of mortality after spine surgery (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.35-1.97; p<0.001). No differences between the sexes were identified for the odds of complications (OR, 1.04; 95% CI, 0.95-1.13; p=0.42).

CONCLUSIONS

Our results determined that males were at elevated odds of mortality but not of complications after spine surgery. These results should be used to inform preoperative discussion and decision-making at the time of surgical consent. Future work should be directed at determining the underlying factors responsible for increased mortality among males and prospective studies specifically designed to evaluate sex-based differences in outcomes after spine surgery.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Female sex protects from organ failure and sepsis after major trauma haemorrhage

INTRODUCTION

Biological sex is considered a risk factor for adverse outcome after major trauma. We hypothesized that female sex is protective against organ failure, sepsis and mortality in patients with traumatic haemorrhage.

PATIENTS AND METHODS

We selected patients from TraumaRegister DGU(®) (TR-DGU) with primary admission for blunt trauma with an injury severity score ≥ 16 and an ICU stay ≥ 3 days that presented with relevant bleeding in the years 2007-2012. Relevant bleeding was defined as Abbreviated Injury Scale (AIS) ≥ 3 with an estimated blood loss exceeding 20%, any femoral shaft fracture, any pelvic clamp as surrogate for unstable pelvic fracture or the presence of at least one criteria of haemorrhagic shock: shock index of 0.8-1.4; base excess of -2.0 to -10.0 mmol/L; body temperature ≤ 34°C; transfusion of ≥ 4 units of packed red blood cells; application of recombinant activated factor VII; any embolization during trauma room phase and pre-hospital resuscitation volume ≥ 3000 ml or any catecholamine use during pre-hospital care in the absence of cardiopulmonary resuscitation. A total of 7560 males and 2774 females were selected and analyzed for sex differences.

RESULTS

Higher rates of multiple organ failure (24.4 vs. 21.3%, Odds ratio [OR] 1.19 (95% confidence interval [95%CI] 1.07-1.33), p=0.001*) and sepsis (16.5 vs. 11.3%, OR 1.55 (95%CI 1.35-1.77), p<0.001*) were observed in males. Organ function of lung, cardio-circulatory system, liver and kidney were better in females, however, there was no difference in mortality. Stratification by age group revealed that in particular age-group 16-44 years was related to improved organ function which may indicate effects of sex hormones in females at reproductive age. Increased rates of sepsis in males were observed throughout virtually all age groups starting at 16 years of age, except in age group 54-64 years. This may suggest suppressive effect of testosterone on immune function.

CONCLUSIONS

Our study supports the hypothesis that female sex is associated with improved organ function following traumatic injury and haemorrhagic shock, in particular in age groups that are at reproductive age. However, further studies are warranted before sex steroids can be deployed as therapeutic intervention in critically ill trauma patients.