Sex differences in survival after out-of-hospital cardiac arrest: a meta-analysis

Sex differences in extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest: nationwide multicenter retrospective study in Japan

BACKGROUND

Previous studies examining sex differences in patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) have indicated that women have favorable outcomes; however, detailed evidence remains lacking. We aimed to investigate sex differences in the backgrounds and outcomes of patients undergoing ECPR for OHCA.

METHODS

This study was a secondary analysis of the registry from the SAVE-J II study, a retrospective multicenter study conducted in Japan from 2013 to 2018. Adult patients without external causes who underwent ECPR for OHCA were included. The primary outcome was a favorable neurological outcome (Cerebral Performance Status 1 or 2) at hospital discharge. We used multilevel logistic regression to evaluate the association of sex differences, adjusting for center-level (hospital) and individual-level variables (patient background, cardiac arrest situation, and in-hospital intervention factors). For sensitivity analyses, we performed three models of multilevel logistic regression when selecting confounders.

RESULTS

Among the 1819 patients, 1523 (83.7%) were men, and 296 (16.3%) were women. The median age (61.0 vs. 58.0 years), presence of a witness (78.8% vs. 79.2%), and occurrence of bystander CPR (57.5% vs. 61.6%) were similar between groups. Women were more likely to present with an initial non-shockable rhythm (31.7% vs. 49.7%), as well as a non-shockable rhythm at hospital arrival (52.1% vs. 61.5%) and at ECMO initiation (48.1% vs. 57.1%). The proportion of favorable neurological outcomes was 12.3% in males and 15.9% in females (p = 0.10). Multilevel logistic regression analysis showed that the female sex was significantly associated with a favorable neurologic outcome at discharge (adjusted odds ratio: 1.60 [95% confidence interval: 1.05-2.43]; p = 0.03). This advantage in women was consistently observed in the sensitivity analyses.

CONCLUSIONS

The female sex is significantly associated with favorable neurological outcomes at hospital discharge in patients who received ECPR for OHCA.

Sex and 30-day survival following out-of-hospital cardiac arrest in Scotland 2011-2020

BACKGROUND

Differences in 30-day survival between males and females following out-of-hospital cardiac arrest (OHCA) are well documented. Biological sex does not appear to be responsible for this survival gap independently of potential mediating factors. We investigated the role of potential mediating factors in the association between sex and 30-day survival after OHCA in Scotland.

METHODS

A retrospective cohort study of adult non-emergency medical services (EMS)-witnessed OHCA cases was conducted. We included incidents from the whole of Scotland where resuscitation was attempted by the Scottish Ambulance Service (SAS) between April 1, 2011 and March 1, 2020. Logistic regression was used to assess the contribution of age, socioeconomic status, urban-rural location of the incident, initial cardiac rhythm, bystander cardiopulmonary resuscitation (CPR) and location of the arrest (home or away from home).

RESULTS

The cohort consisted of 20,585 OHCA cases (13,130 males and 7,455 females). Median (IQR) age was 69 years (22) for males versus 72 years (23) for females. A higher proportion of males presented with initial shockable rhythm (29.4% versus 12.4%) and received bystander CPR (56.7% versus 53.2%) compared with females. A higher proportion of females experienced OHCA at home (78.8% versus 66.8%). Thirty-day survival after OHCA was higher for males compared with females (8.2% versus 6.2%). Males had higher age-adjusted odds for 30-day survival after OHCA than females (OR, 1.26; (95% CI), 1.12-1.41). Mediation analyses suggested a role for initial cardiac rhythm and location of the arrest (home or away from home).

CONCLUSION

Males had higher age-adjusted 30-day survival after OHCA than females. However, after adjusting for confounding/mediating variables, sex was not associated with 30-day survival after OHCA. Our findings suggest that initial cardiac rhythm and location of the arrest are potential mediators of higher 30-day OHCA survival in males than females. Improving proportions of females who present with initial shockable rhythm may reduce sex differences in survival after OHCA.

Sex hormone trajectories and association to outcomes after out-of-hospital cardiac arrest

BACKGROUND

Outcomes and susceptibility to out-of-hospital cardiac arrest (OHCA) are known to differ by sex, yet little is known about changes in sex hormones after OHCA. We sought to determine the trajectory of sex hormones after OHCA and their association to survival and neurological outcome.

METHODS

Plasma samples were collected from those that survived to hospital admission at four time points (1, 6, 24, and 48 h) and estrone, estradiol, progesterone, and testosterone concentrations were quantified via liquid chromatography-mass spectrometry. Trends in hormones were plotted over time by sex and outcomes. The association between sex, hormone levels with survival and neurological outcome (cerebral performance category 1-2 indicating good outcome and 3-5 for poor outcome) were determined using generalized estimating equation models.

RESULTS

Of the 94 OHCA patients, 50 were males and 44 females, with a mean age of 61.3 (+15.7) years. Despite older age and lower BCPR in females compared to males, females had higher proportion of good neurological outcome compared to males. Over the 48 h, estrone increased, testosterone decreased, and estradiol and progesterone remained flat. Survivors had lower levels of estrone at all time points but only at early time points for estradiol, progesterone and testosterone. Lower estrone level predicted survival at discharge, even after adjusting for time, sex, age, and hormones independently (β = -3.38, 95% CI = -5.71, -0.85). Females had better neurological scores compared to males after adjusting for estrone (β = 1.27, 95% CI = 0.01, 2.53) and estradiol (β = 2.92, 95% CI = 1.13, 4.70).

CONCLUSIONS

Survivors and those with favorable neurological outcome had lower trend in estrone. The sex hormone estrone, present in both males and females, may be a predictor of survival. When adjusted for estrogens, female sex had better neurological recovery compared to males. The difference in neurological outcome by sex is not explained by estrogens. However, these finding open the door for exploration of other sex-specific pathways in resuscitation after OHCA.

Global Sex Disparities in Bystander Cardiopulmonary Resuscitation After Out-of-Hospital Cardiac Arrest: A Scoping Review

This scoping review collates evidence for sex biases in the receipt of bystander cardiopulmonary resuscitation (BCPR) among patients with out-of-hospital cardiac arrest patients globally. The MEDLINE, PsycINFO, CENTRAL, and Embase databases were screened for relevant literature, dated from inception to March 9, 2022. Studies evaluating the association between BCPR and sex/gender in patients with out-of-hospital cardiac arrest, except for pediatric populations and cardiac arrest cases with traumatic cause, were included. The review included 80 articles on BCPR in men and women globally; 58 of these studies evaluated sex differences in BCPR outcomes. Fifty-nine percent of the relevant studies (34/58) indicated that women are less likely recipients of BCPR, 36% (21/58) observed no significant sex differences, and 5% (3/58) reported that women are more likely to receive BCPR. In other studies, women were found to be less likely to receive BCPR in public but equally or more likely to receive BCPR in residential settings. The general reluctance to perform BCPR on women in the Western countries was attributed to perceived frailty of women, chest exposure, pregnancy, gender stereotypes, oversexualization of women's bodies, and belief that women are unlikely to experience a cardiac arrest. Most studies worldwide indicated that women were less likely to receive BCPR than men. Further research from non-Western countries is needed to understand the impact of cultural and socioeconomic settings on such biases and design customized interventions accordingly.

Incidence, characteristics, and prehospital outcomes of out-of-hospital cardiac arrest in Qatar: a nationwide gender-based investigation

BACKGROUND

Research on incidence and characteristics of Out-of-Hospital Cardiac Arrest (OHCA) in the Middle East is limited. We assessed the incidence, prehospital characteristics, and outcomes of OHCA in Qatar, a Middle Eastern country. Subsequently, we performed gender-specific analysis.

METHODS

This was a retrospective examination of data obtained from the OHCA registry at Hamad Medical Corporation (HMC) in Qatar from 2017 to 2022. We included adults, non-traumatic, EMS-treatment OHCA. We calculated the incidence of adult OHCA and conducted descriptive analyses for prehospital characteristics, and prehospital outcomes presented by return of spontaneous circulation (ROSC). We evaluated gender differences in prehospital characteristics and ROSC using Student's t-test and the Chi-Square test as appropriate. Furthermore, we conducted a multivariable logistic regression analysis to investigate the correlation between gender and achieving ROSC.

RESULTS

We included 4,306 adult OHCA patients, with 869 (20.2%) being females. The mean annual incidence of adult OHCA was 27.4 per 100,000 population-year. Males had a higher annual incidence of OHCA than females. Among all cases, 36.3% occurred in a public location, 25.8% had an initial shockable rhythm, and 28.8% achieved ROSC. Males had a higher proportion of bystander CPR, arrests in public locations, and initial shockable rhythms. While unadjusted analysis showed no significant gender differences in achieving ROSC, adjusted analysis revealed that male gender was associated with higher odds of achieving ROSC (adjusted OR male vs. female 1.38, 95% CI 1.15-1.66, p < 0.001).

CONCLUSIONS

Approximately 720 adults undergo non-traumatic OHCA in Qatar every year, with a higher incidence observed in males. Male gender was associated with higher odds of achieving ROSC. Further gender-specific research in OHCA intervention and outcome in the Middle East is required.

Long-Term Socioeconomic and Mental Health Changes After Out-of-Hospital Cardiac Arrest in Women and Men

BACKGROUND

Long-term effects of out-of-hospital cardiac arrest (OHCA) may affect the ability to work and mental health. Our aim was to analyze 5-year changes in socioeconomic and mental health outcomes after OHCA in women and men.

METHODS

We included 259 women and 996 men from North Holland, the Netherlands, who survived 30 days after OHCA occurred between 2009 and 2015. We assessed changes in employment, income, primary earner status, and anxiety/depression (using medication proxies) from the year before the OHCA to 5 years after with generalized linear mixed models, stratified by sex. We tested differences in changes by sex with interaction terms. Additionally, we explored yearly changes. The 5-year changes after OHCA were compared with changes in a sex- and age-matched sample of people without OHCA. Differences were tested using an interaction term of time and OHCA status.

RESULTS

In both women and men (median age [Q1, Q3]: 51 [45, 55] and 54 [48, 57] years, respectively), decreases from before OHCA to 5 years thereafter were observed in the proportion employed (from 72.8% to 53.4% [women] and 80.9% to 63.7% [men]) and the median income. No change in primary earner status was observed in either sex. Dispensing of anxiety/depression medication increased only in women, especially after 1 year (odds ratio, 5.68 [95% CI, 2.05-15.74]) and 5 years (odds ratio, 5.73 [95% CI, 1.88-17.53]). Notable differences between women and men were observed for changes in primary earner status and anxiety/depression medication (eg, at year 1, odds ratio for women, 6.71 [95% CI, 1.96-23.01]; and for men, 0.69 [95% CI, 0.33-1.45]). However, except for anxiety/depression medication in women, similar changes were also observed in the general population.

CONCLUSIONS

OHCA survivors experience changes in employment, income, and primary earner status similar to the general population. However, women who survived OHCA more often received anxiety/depression medication in the years following OHCA.

Variable importance analysis with interpretable machine learning for fair risk prediction

Machine learning (ML) methods are increasingly used to assess variable importance, but such black box models lack stability when limited in sample sizes, and do not formally indicate non-important factors. The Shapley variable importance cloud (ShapleyVIC) addresses these limitations by assessing variable importance from an ensemble of regression models, which enhances robustness while maintaining interpretability, and estimates uncertainty of overall importance to formally test its significance. In a clinical study, ShapleyVIC reasonably identified important variables when the random forest and XGBoost failed to, and generally reproduced the findings from smaller subsamples (n = 2500 and 500) when statistical power of the logistic regression became attenuated. Moreover, ShapleyVIC reasonably estimated non-significant importance of race to justify its exclusion from the final prediction model, as opposed to the race-dependent model from the conventional stepwise model building. Hence, ShapleyVIC is robust and interpretable for variable importance assessment, with potential contribution to fairer clinical risk prediction.

Impact of Preexisting Depression and Anxiety on Hospital Readmission and Long-Term Survival After Cardiac Arrest

BACKGROUND

While sudden cardiac arrest (CA) survivors are at risk for developing psychiatric disorders, little is known about the impact of preexisting mental health conditions on long-term survival or postacute healthcare utilization. We examined the prevalence of preexisting psychiatric conditions in CA patients who survived hospital discharge, characterized incidence and reason for inpatient psychiatry consultation during these patients' acute hospitalizations, and determined the association of pre-CA depression and anxiety with hospital readmission rates and long-term survival. We hypothesized that prior depression or anxiety would be associated with higher hospital readmission rates and lower long-term survival.

METHODS

We conducted a retrospective cohort study including patients resuscitated from in- and out-of-hospital CA who survived both admission and discharge from a single hospital between January 1, 2010, and December 31, 2017. We identified patients from our prospective registry, then performed a structured chart review to abstract past psychiatric history, prescription medications for psychiatric conditions, and identify inpatient psychiatric consultations. We used administrative data to identify readmissions within 1 year and vital status through December 31, 2020. We used multivariable Cox regressions controlling for patient demographics, medical comorbidities, discharge Cerebral Performance Category and disposition, depression, and anxiety history to predict long-term survival and hospital readmission.

RESULTS

We included 684 subjects. Past depression or anxiety was noted in 24% (n = 162) and 19% (n = 129) of subjects. A minority of subjects (n = 139, 20%) received a psychiatry consultation during the index hospitalization. Overall, 262 (39%) subjects had at least 1 readmission within 1 year. Past depression was associated with an increased hazard of hospital readmission (hazard ratio 1.50, 95% CI 1.11-2.04), while past anxiety was not associated with readmission. Neither depression nor anxiety were independently associated with long-term survival.

CONCLUSIONS

Depression is an independent risk factor for hospital readmission in CA survivors.

Epidemiology and outcome of out-of-hospital cardiac arrest in Salt Lake City: Sex-based investigations

Objectives

Prior research indicates sex disparities in the incidence and outcomes of out-of-hospital cardiac arrest (OHCA). This study investigates the presence of such differences in Salt Lake City, Utah.

Methods

We analyzed data from the Salt Lake City Fire Department (2008‒2023). We included adults with non-traumatic OHCA. We calculated the annual incidence of OHCA and examined sex-specific survival outcomes using multivariable logistic regression, adjusting for OHCA characteristics known to be associated with survival.

Results

The annual incidence of OHCA was 76 per 100,000 person-years. Among the 894 OHCA cases included in the analysis, 67.5% were males, 37.3% achieved return of spontaneous circulation (ROSC), and 13.6% survived hospital discharge. Unadjusted analysis revealed that males had significantly higher OHCA in public locations (43.9% vs. 28.6%), witnessed arrests (54.5% vs. 47.8%), and shockable rhythms (33.3% vs. 22.9%). Males also showed higher rates of ROSC (37.5% vs. 36.9%), hospital discharge survival (14.5% vs. 11.7%), and neurologically intact survival. After adjusting for the OHCA characteristics, there was no significant differences between males and females in ROSC, survival to hospital discharge, and favorable neurological function with adjusted odds ratios (male vs. female) of 0.92 (95% confidence interval [CI] 0.73‒1.16), 0.85 (95% CI 0.59‒1.22), and 0.92 (95% CI 0.62‒1.40), respectively.

Conclusion

Approximately, 128 adults suffer OHCA in Salt Lake City annually. Males initially showed higher crude survival rates, but after adjusting for OHCA characteristics, no significant sex differences in survival outcomes were found. Enhancing OHCA characteristics could benefit both sexes. Investigations into the relationship between sex- and region-specific factors influencing OHCA outcomes are needed.

Impact of sex of bystanders who perform cardiopulmonary resuscitation on return of spontaneous circulation in out-of-hospital cardiac arrest patients: A retrospective, observational study

Background

The impact of the sex of bystanders who initiate cardiopulmonary resuscitation (CPR) on out-of-hospital cardiac arrest (OHCA) patients has not been fully elucidated. This study aims to investigate the association between the sex of bystanders who perform CPR and the clinical outcomes of OHCA patients in real-world clinical settings.

Methods

We conducted a retrospective, observational study using data from the Okayama City Fire Department in Japan. Patients were categorized based on bystanders' sex. Our primary outcomes were return of spontaneous circulation (ROSC). Our secondary outcome was 30-day survival and 30-day favorable neurological outcome, defined as Cerebral Performance Category score of 1 or 2. Multivariable logistic regression analysis was used to examine the association between these groups and outcomes.

Results

The study included 3,209 patients with a comparable distribution of male (1,540 patients: 48.0%) and female bystanders (1,669 patients: 52.0%) between the groups. Overall, 221 (6.9%) ROSC at hospital arrival, 226 (7.0%) patients had 30-day survival, and 121 (3.8%) patients had 30-day favorable neurological outcomes. Bystander sex (female as reference) did not contribute to ROSC at hospital arrival (adjusted OR [aOR] 1.11, 95% CI: 0.76-1.61), 30-day survival (aOR 1.23, 95% CI: 0.83-1.82), or 30-day favorable neurological outcomes (aOR 0.66, 95% CI: 0.34-1.27). Basic life support education experience was a bystander factor positively associated with ROSC. Patient factors positively associated with ROSC were initial shockable rhythm and witness of cardiac arrest.

Conclusion

There were no differences in ROSC, 30-day survival, or 30-day neurological outcomes in OHCA patients based on bystander sex.

Gender Disparities in Cardiovascular Disease and Their Management: A Review

Worldwide, cardiovascular diseases (CVDs) are still the primary cause of death, and there are notable differences between sexes when it comes to symptoms/course and treatment. Due to evolving healthcare technologies, significant progress has been made in understanding CVDs. Hence, it is evident that gender disparities exist in the clinical presentation, prevalence, management, outcomes, and risk factors, including biological, behavioral, and sociocultural factors. This narrative review is designed to provide a generalized idea of gender disparities in CVDs. It aims to provide insights to prove the role of hormonal influences, genetic predispositions, and the difference in physiological outcomes owing to different genders. This review explores subtle distinctions in CVD across genders, including changes in structure, biology, and hormones that affect how illness presents and progresses. Lifestyle variables also influence sociocultural factors and gender disparities in risk profiles. Traditional risk factors, diabetes mellitus (DM), cholesterol levels, and smoking may have different weights and relevance in men and women. Moreover, age and other conventional risk variables have distinct effects on gender. Treatment efficacy may be impacted by the expression of gender-specific factors, emphasizing the necessity for customized strategies. Development of CVDs can be delayed or prevented, and its consequences can be lessened with the early identification and effective management of gender-specific factors. More investigation is necessary to clarify complex interactions between structural, biochemical, and hormonal aspects across genders in order to maximize treatment results and reduce the burden of CVDs.

Sex Differences in Out-of-Hospital Cardiac Arrest Survival Trends

BACKGROUND

Out-of-hospital cardiac arrest survival rates have improved over time. This study established whether improvements were similar for women and men, and to what extent resuscitation characteristics or in-hospital procedures contributed to sex differences in temporal trends.

METHODS AND RESULTS

This retrospective cohort study included 3386 women and 8564 men from North Holland, the Netherlands, who experienced an out-of-hospital cardiac arrest from a cardiac cause in 2005 to 2017. Yearly rates of 30-day survival and secondary outcomes were calculated. Sex differences in temporal trends were evaluated with age-adjusted Poisson regression analysis, including interaction for sex and out-of-hospital cardiac arrest year. Resuscitation characteristics and in-hospital procedures were added to the model, and a spline at 2013 was considered. During the study period, the average 30-day survival was 24.9% in men and 15.7% in women. The 30-day survival rate increased in men (20% to 27.2%; P<0.001) but not in women (15.0% to 11.6%; P=0.40). The increase in the 30-day survival rate was 3% higher per year in men than in women (rate ratio, 1.03 [95% CI, 1.00-1.05]), with a stronger difference after 2013. Men had a larger increase in survival rate to the hospital arrival than women in 2005 to 2013, and, after 2013, an advantage over women in survival rate after hospital arrival. The sex differences were partly explained by differing trends in shockable initial rhythm (eg, adjusted rate ratio, 1.01 [95% CI, 0.99-1.03] for 30-day survival) and provision of in-hospital procedures.

CONCLUSIONS

Changes in rates of 30-day survival, survival to hospital arrival, and, after 2013, survival from hospital arrival to 30 days were more beneficial in men than women. The differences in trends were partly explained by shockable initial rhythm and in-hospital procedures.

Relationship between initial red cell distribution width and ΔRDW and mortality in cardiac arrest patients

AIMS

There has been a lack of research examining the relationship between red cell distribution width (RDW) and the prognosis of cardiac arrest (CA) patients. The prognostic value of the changes in RDW during intensive care unit (ICU) hospitalization for CA patients has not been investigated. This study aims to investigate the correlation between RDW measures at ICU admission and RDW changes during ICU hospitalization and the prognosis of CA patients and then develop a nomogram that predicts the risk of mortality of these patients.

METHODS AND RESULTS

A retrospective cohort study is used to collect clinical characteristics of CA patients (>18 years) that are on their first admission to ICU with RDW data measured from the Medical Information Mart for Intensive Care IV Version 2.0 database. Patients are randomly divided into a development cohort (75%) and a validation cohort (25%). The primary outcome is 30 and 360 day all-cause mortality. ΔRDW is defined as the RDW on ICU discharge minus RDW on ICU admission. A multivariate Cox regression model is applied to test whether the RDW represents an independent risk factor that affects the all-cause mortality of these patients. Meanwhile, the dose-response relationship between the RDW and the mortality is described by restricted cubic spine (RCS). A prediction model is constructed using a nomogram, which is then assessed using receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA). A total of 1278 adult CA patients are included in this study. We found that non-survivors have a higher level of RDW and ΔRDW compared with survivors, and the mortality rate is higher in the high RDW group than in the normal RDW group. The Kaplan-Meier survival curve indicates that patients in the normal RDW group had a higher cumulative survival rate at 30 and 360 days than those in the high RDW group (log-rank test, χ2  = 36.710, χ2  = 54.960, both P values <0.05). The multivariate Cox regression analysis shows that elevated RDW at ICU admission (>15.50%) is an independent predictor of 30 [hazard ratio = 1.451, 95% confidence interval (CI) = 1.181-1.782, P < 0.001] and 360 day (hazard ratio = 1.393, 95% CI = 1.160-1.671, P < 0.001) all-cause mortality among CA patients, and an increase in RDW during ICU hospitalization (ΔRDW ≥ 0.4%) can serve as an independent predictor of mortality among these patients. A non-linear relationship between the RDW measured at ICU admission and the increased risk of mortality rate of these patients is shown by the RCS. This study established and validated a nomogram based on six variables, anion gap, first-day Sequential Organ Failure Assessment score, cerebrovascular disease, malignant tumour, norepinephrine use, and RDW, to predict mortality risk in CA patients. The consistency indices of 30 and 360 day mortality of CA patients in the validation cohort are 0.721 and 0.725, respectively. The nomogram proved to be well calibrated in the validation cohort. DCA curves indicated that the nomogram provided a higher net benefit over a wide, reasonable range of threshold probabilities for predicting mortality in CA patients and could be adapted for clinical decision-making.

CONCLUSIONS

Elevated RDW levels on ICU admission and rising RDW during ICU hospitalization are powerful predictors of all-cause mortality for CA patients at 30 and 360 days, and they can be used as potential clinical biomarkers to predict the bad prognosis of these patients. The newly developed nomogram, which includes RDW, demonstrates high efficacy in predicting the mortality of CA patients.

Association of sex with post-arrest care and outcomes after out-of-hospital cardiac arrest of initial shockable rhythm: a nationwide cohort study

Background

Research has described differences in the provision of prehospital treatment for women who experience out-of-hospital cardiac arrest. However, studies have reported conflicting results regarding survival outcomes or in-hospital interventions between sexes. Thus, this study aimed to investigate the association of sex with survival outcomes and in-hospital treatments in Japan.

Methods

We retrospectively analyzed data from the Japanese Association for Acute Medicine-Out-of-Hospital Cardiac Arrest Registry. Patients aged ≥18 years who presented with a shockable rhythm at the scene between June 2014 and December 2020 were included in our analysis. Outcome measures were 30-day survival and in-hospital interventions. We compared the outcomes between the sexes using multivariable logistic regression.

Results

In total, 5,926 patients (4,270 men; 1,026 women) with out-of-hospital cardiac arrest were eligible for our analysis. The proportions of patients with 30-day survival outcomes were 39.5% (1685/4,270) and 37.4% (384/1,026) in the male and female groups, respectively (crude odds ratio, 0.92; 95% confidence interval, 0.80-1.06). Although there were no significant differences, survival outcomes tended to be better in women than in men in the multiple regression analysis (adjusted odds ratio: 1.38; 95% confidence interval: 0.82-2.33). Furthermore, there was no significant difference between the sexes in terms of patients who received extracorporeal cardiopulmonary resuscitation (adjusted odds ratio: 0.81; 95% confidence interval: 0.49-1.33) or targeted temperature management (adjusted odds ratio: 0.99; 95% confidence interval: 0.68-1.46).

Conclusions

After adjusting for prognostic factors, there were no differences in survival rates and in-hospital interventions between men and women.

Gender-related differences in adults concerning frequency, survival and treatment quality after out-of-hospital cardiac arrest (OHCA): An observational cohort study from the German resuscitation registry

BACKGROUND

In Germany approximately 20,500 women and 41,000 men were resuscitated after out-of-hospital cardiac arrest (OHCA) each year. We are currently experiencing a discussion about the possible undersupply of women in healthcare. The aim of the present study was to examine the prevalence of OHCA in Germany, as well as the outcome and quality of resuscitation care for both women and men.

METHODS

We present a cohort study from the German Resuscitation Registry (2006-2022). The quality of care was assessed for both EMS and hospital care based on risk-adjusted survival rates with the endpoints: "hospital admission with return of spontaneous circulation" (ROSCadmission) for all patients and "discharge with favourable neurological recovery" (CPC1/2discharge) for all admitted patients. Risk adjustment was performed using logistic regression analysis (LRA). If sex was significantly associated with survival, a matched-pairs-analysis (MPA) followed to explore the frequency of guideline adherence.

RESULTS

58,798 patients aged ≥ 18 years with OHCA and resuscitation were included (men = 65.2%, women = 34.8%). In the prehospital phase the male gender was associated with lower ROSCadmission-rate (LRA: OR = 0.79, CI = 0.759-0.822). A total of 27,910 patients were admitted. During hospital care, men demonstrated a better prognosis (OR = 1.10; CI = 1.015-1.191). MPA revealed a more intensive therapy for men both during EMS and hospital care. Looking at the complete chain of survival, LRA revealed no difference for men and women concerning CPC1/2discharge (n = 58,798; OR = 0.95; CI = 0.888-1.024).

CONCLUSION

In Germany, 80% more men than women experience OHCA. The prognosis for CPC1/2discharge remains low (men = 10.5%, women = 7.1%), but comparable after risk adjustment. There is evidence of undersupply of care for women during hospital treatment, which could be associated with a worse prognosis. Further investigations are required to clarify these findings.

Prognostic factors associated with favourable functional outcome among adult patients requiring extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR), has demonstrated promise in the management of refractory out-of-hospital cardiac arrest (OHCA). However, evidence from observational studies and clinical trials are conflicting and the factors influencing outcome have not been well established.

METHODS

We conducted a systematic review and meta-analysis summarizing the association between pre-ECPR prognostic factors and likelihood of good functional outcome among adult patients requiring ECPR for OHCA. We searched Medline and Embase databases from inception to February 28, 2023 and screened studies with two independent reviewers. We performed meta-analyses of unadjusted and adjusted odds ratios, adjusted hazard ratios and mean differences separately. We assessed risk of bias using the QUIPS tool and certainty of evidence using the GRADE approach.

FINDINGS

We included 29 observational and randomized studies involving 7,397 patients. Factors with moderate or high certainty of association with increased survival with favourable functional outcome include pre-arrest patient factors, such as younger age (odds ratio (OR) 2.13, 95% CI 1.52 to 2.99) and female sex (OR 1.37, 95% CI 1.11 to 1.70), as well as intra-arrest factors, such as shockable rhythm (OR 2.79, 95% CI 2.04 to 3.80), witnessed arrest (OR 1.68 (95% CI 1.16 to 2.42), bystander CPR (OR 1.55, 95% CI 1.19 to 2.01), return of spontaneous circulation (OR 2.81, 95% CI 2.19 to 3.61) and shorter time to cannulation (OR 1.14, 95% CI 1.17 to 1.69 per 10 minutes).

INTERPRETATION

The findings of this review confirm several clinical concepts wellestablished in the cardiac arrest literature and their applicability to the patient for whom ECPR is considered - that is, the impact of pre-existing patient factors, the benefit of timely and effective CPR, as well as the prognostic importance of minimizing low-flow time. We advocate for the thoughtful consideration of these prognostic factors as part of a risk stratification framework when evaluating a patient's potential candidacy for ECPR.

[Morbidity due to chronic diseases and their health care in Asturias: a gender analysis]

OBJECTIVE

To determine gender differences in the magnitude and complexity of chronic diseases and gender inequalities in health care in the adult population of Asturias in 2022.

METHOD

A cross-sectional population study in people (>14 years) with at least one diagnosis of chronic disease (780,566 inhabitants).

SOURCES OF INFORMATION

computer program for morbidity groups (Ministry of Health), Electronic medical record of primary care and hospital. Comparative analysis by sex and age, the mean values of chronic diseases and complexity index (Student's t test and one-way ANOVA), and probability (odds ratio and 95% CI) of suffering from specific chronic diseases, making one or more visits to the hospital emergency department or one or more admissions to hospital.

RESULTS

89.9% of women and 82.1% of men were registered with at least one chronic disease. The mean was higher in women (4.36) than in men (3.22) (p<0.001). Complexity index: men 4.56 and women 5.85 (p<0.001). Results show that women are more likely to attend the hospital emergency department, with an attendance rate of 50% for the diseases cited, compared with men at 29%. The rate of hospital admission is higher in men in 13 of the 14 diseases studied (85%).

CONCLUSIONS

Gender analysis can also be applied to secondary sources of the National Health System. Despite the greater magnitude and complexity of chronic diseases in women, there is a higher frequency of hospital admissions in men compared to women with the same diseases. This implies an unequal care profile in the field of hospital admissions that the scientific literature associates with gender biases in health care.

Sex and gender differences in intensive care medicine

Despite significant advancements in critical care medicine, limited attention has been given to sex and gender disparities in management and outcomes of patients admitted to the intensive care unit (ICU). While "sex" pertains to biological and physiological characteristics, such as reproductive organs, chromosomes and sex hormones, "gender" refers more to sociocultural roles and human behavior. Unfortunately, data on gender-related topics in the ICU are lacking. Consequently, data on sex and gender-related differences in admission to the ICU, clinical course, length of stay, mortality, and post-ICU burdens, are often inconsistent. Moreover, when examining specific diagnoses in the ICU, variations can be observed in epidemiology, pathophysiology, presentation, severity, and treatment response due to the distinct impact of sex hormones on the immune and cardiovascular systems. In this narrative review, we highlight the influence of sex and gender on the clinical course, management, and outcomes of the most encountered intensive care conditions, in addition to the potential co-existence of unconscious biases which may also impact critical illness. Diagnoses with a known sex predilection will be discussed within the context of underlying sex differences in physiology, anatomy, and pharmacology with the goal of identifying areas where clinical improvement is needed. To optimize patient care and outcomes, it is crucial to comprehend and address sex and gender differences in the ICU setting and personalize management accordingly to ensure equitable, patient-centered care. Future research should focus on elucidating the underlying mechanisms driving sex and gender disparities, as well as exploring targeted interventions to mitigate these disparities and improve outcomes for all critically ill patients.

The Lancet Commission to reduce the global burden of sudden cardiac death: a call for multidisciplinary action

Despite major advancements in cardiovascular medicine, sudden cardiac death (SCD) continues to be an enormous medical and societal challenge, claiming millions of lives every year. Efforts to prevent SCD are hampered by imperfect risk prediction and inadequate solutions to specifically address arrhythmogenesis. Although resuscitation strategies have witnessed substantial evolution, there is a need to strengthen the organisation of community interventions and emergency medical systems across varied locations and health-care structures. With all the technological and medical advances of the 21st century, the fact that survival from sudden cardiac arrest (SCA) remains lower than 10% in most parts of the world is unacceptable. Recognising this urgent need, the Lancet Commission on SCD was constituted, bringing together 30 international experts in varied disciplines. Consistent progress in tackling SCD will require a completely revamped approach to SCD prevention, with wide-sweeping policy changes that will empower the development of both governmental and community-based programmes to maximise survival from SCA, and to comprehensively attend to survivors and decedents' families after the event. International collaborative efforts that maximally leverage and connect the expertise of various research organisations will need to be prioritised to properly address identified gaps. The Commission places substantial emphasis on the need to develop a multidisciplinary strategy that encompasses all aspects of SCD prevention and treatment. The Commission provides a critical assessment of the current scientific efforts in the field, and puts forth key recommendations to challenge, activate, and intensify efforts by both the scientific and global community with new directions, research, and innovation to reduce the burden of SCD worldwide.

Sex Difference on Neurological Outcomes and Post-Cardiac Arrest Care in Out-of-Hospital Cardiac Arrest Patients Treated with Targeted Temperature Management: Post-Hoc Study of a Prospective, Multicenter, Observational Cohort Study

Conflicting results regarding sex-based differences in the outcomes of out-of-hospital cardiac arrest (OHCA) patients have been reported. We aimed to evaluate the association between sex and neurological outcome as well as various in-hospital process in OHCA patients treated with targeted temperature management. We retrospectively analyzed a prospective registry data collected between October 2015 and December 2018. To evaluate the effect of sex on patient outcomes, we created various multivariable logistic regression models. When the results were adjusted using resuscitation variables and in-hospital variables, there was no significant difference (OR = 1.22, 95% CI: 0.85-1.74; OR = 1.13, 95 CI: 0.76-1.68, respectively). Regarding the in-hospital course, the daily total SOFA score was similar in both sexes, whereas cardiovascular scores were higher in women on days 2 and 3. The adjusted effect of sex was not associated with the clinician's decision to perform early cardiac interventions, except for those men that had more extracorporeal membrane oxygenation (OR = 2.51, 95% CI: 1.11-5.66). The findings seems that men had more favorable 6-month neurological outcomes. However, after adjusting for confounders, there was no difference between the sexes. The results regarding in-hospital course were similar in men and women.

One-year survival after out-of- hospital cardiac arrest: Sex-based survival analysis in a Canadian population

Objective

We investigated sex differences in 1-year survival in a cohort of patients who survived out-of-hospital cardiac arrest (OHCA) to hospital discharge. We hypothesized that female sex is associated with higher 1-year posthospital discharge survival.

Methods

A retrospective analysis of linked data (2011-2017) from clinical databases in British Columbia (BC) was conducted. We used Kaplan-Meier curves, stratified by sex, to display survival up to 1-year, and the log-rank test to test for significant sex differences. This was followed by multivariable Cox proportional hazards analysis to investigate the association between sex and 1-year mortality. The multivariable analysis adjusted for variables known to be associated with survival, including variables related to OHCA characteristics, comorbidities, medical diagnoses, and in-hospital interventions.

Results

We included 1278 hospital-discharge survivors; 284 (22.2%) were female. Females had a lower proportion of OHCA occurring in public locations (25.7% vs. 44.0%, P < 0.001), a lower proportion with a shockable rhythm (57.7% vs. 77.4%, P < 0.001), and fewer hospital-based acute coronary diagnoses and interventions. One-year survival for females and males was 90.5% and 92.4%, respectively (log-rank P = 0.31). Unadjusted (hazard ratio [HR] males vs. females 0.80, 95% confidence interval [CI] 0.51-1.24, P = 0.31) and adjusted (HR males vs. females 1.14, 95% CI 0.72-1.81, P = 0.57) models did not detect differences in 1-year survival by sex.

Conclusion

Females have relatively unfavorable prehospital characteristics in OHCA and fewer hospital-based acute coronary diagnoses and interventions. However, among survivors to hospital discharge, we found no significant difference between males and females in 1-year survival, even after adjustment.

A more conservative test of sex differences in the treatment and outcome of in-hospital cardiac arrest

BACKGROUND

Studies investigating sex disparities related to treatment and outcome of in-hospital cardiac arrest (IHCA) have produced divergent findings and have typically been unable to adjust for outstanding confounding variables.

OBJECTIVES

The aim was to examine sex differences in treatment and survival following IHCA, using a comprehensive set of control variables including e.g., age, comorbidity, and patient-level socioeconomic status.

METHODS

This retrospective study was based on data from the Swedish Register of Cardiopulmonary Resuscitation and Statistics Sweden. In the primary analyses, logistic regression models and ordinary least square regressions were estimated.

RESULTS

The study included 24,217 patients and the majority (70.4%) were men. In the unadjusted analyses, women had a lower chance of survival after cardiopulmonary resuscitation (CPR) attempt, at hospital discharge (with good neurological function) and at 30 days (p<0.01). In the adjusted regression models, female sex was associated with a higher chance of survival after the CPR attempt (B = 1.09, p<0.01) and at 30-days (B = 1.09, p<0.05). In contrast, there was no significant association between sex and survival to discharge with good neurological outcome. Except for treatment duration (B=-0.07, p<0.01), no significant associations between sex and treatment were identified.

CONCLUSIONS

No signs of treatment disparities or discrimination related to sex were identified. However, women had a better chance of surviving IHCA compared to men. The finding that women went from having a survival disadvantage (unadjusted analysis) to a survival advantage (adjusted analysis) attests to the importance of including a comprehensive set of control variables, when examining sex differences.

Ethnic and sex-based differences in outcomes after out-of-hospital cardiac arrest: a glimpse of the largest municipal healthcare system in the United States

Background

Ethnic and sex-based disparity in outcomes after out-of-hospital cardiac arrest (OHCA) may exist and could be due to social factors and inequality in care. We aimed to study whether ethnic and sex-based differences in out-of-hospital cardiac arrest outcomes occurred in a safety net hospital within the largest municipal healthcare system in the United States.

Methods

We conducted a retrospective cohort study of patients successfully resuscitated from an OHCA and brought to New York City Health + Hospitals/Jacobi, from January 2019 to September 2021. Out-of-hospital cardiac arrest characteristics, do not resuscitate and withdrawal of life-sustaining therapy orders, and disposition data were collected and analyzed using regression models.

Results

Out of 648 patients screened, 154 were included (48.1% women). On multivariable analysis, sex [odds ratio (OR): 0.84; 95% CI: 0.30-2.4; P=0.74] and ethnic background (OR: 0.80; 95% CI: 0.58-1.12; P=0.196) did not predict discharge survival. No significant sex difference in do not resuscitate (P=0.76) or withdrawal of life-sustaining therapy (P=0.39) orders was found. Younger age (OR: 0.96; P=0.04) and initial shockable rhythm (OR: 7.26; P=0.01) independently predicted survival, both at discharge and at one year.

Conclusions

Among patients resuscitated after an out-of-hospital cardiac arrest, neither sex nor ethnic background predicted discharge survival and no sex differences in end-of-life preferences were found. These findings are distinct from those of previously published reports. Given the unique population studied, distinct from those of registry-based studies, socioeconomic factors likely served as bigger drivers of out-of-hospital cardiac arrest outcomes rather than ethnic background or sex.

Bystander basic life support and survival after out-of-hospital cardiac arrest: A propensity score matching analysis

INTRODUCTION AND OBJECTIVES

In out-of-hospital cardiac arrest, early recognition, calling for emergency medical assistance, and early cardiopulmonary resuscitation are acknowledged to be the three most important components in the chain of survival. However, bystander basic life support (BLS) initiation rates remain low. The objective of the present study was to evaluate the association between bystander BLS and survival after an out-of-hospital cardiac arrest (OHCA).

METHODS

We conducted a retrospective cohort study of all patients with OHCA with a medical etiology treated by a mobile intensive care unit (MICU) in France from July 2011 to September 2021, as recorded in the French National OHCA Registry (RéAC). Cases in which the bystander was an on-duty fire fighter, paramedic, or emergency physician were excluded. We assessed the characteristics of patients who received bystander BLS vs. those who did not. The two classes of patient were then matched 1:1, using a propensity score. Conditional logistic regression was then used to probe the putative association between bystander BLS and survival.

RESULTS

During the study, 52,303 patients were included; BLS was provided by a bystander in 29,412 of these cases (56.2%). The 30-day survival rates were 7.6% in the BLS group and 2.5% in the no-BLS group (p < 0.001). After matching, bystander BLS was associated with a greater 30-day survival rate (odds ratio (OR) [95% confidence interval (CI)] = 1.77 [1.58-1.98]). Bystander BLS was also associated with greater short-term survival (alive on hospital admission; OR [95%CI] = 1.29 [1.23-1.36]).

CONCLUSIONS

The provision of bystander BLS was associated with a 77% greater likelihood of 30-day survival after OHCA. Given than only one in two OHCA bystanders provides BLS, a greater focus on life saving training for laypeople is essential.

Neurology of Systemic Disease

Sex differences exist within the neurologic complications of systemic disease. To promote new avenues for prevention and develop novel therapeutics, we highlight the role of sex in differential outcomes to infectious disease and cardiac arrest and educate the reader in paraneoplastic presentations that may herald underlying malignancies in women.

Sex and out-of-hospital cardiac arrest survival: a systematic review

BACKGROUND

The literature is unresolved on whether female receive advanced cardiac life support less than do male and on whether female have a survival advantage over male after cardiopulmonary resuscitation.

METHODS

We systematically searched PubMed, Embase and Web of Science databases (from inception to 23-April-2022) for papers reporting outcomes in adult male and female after out-of-hospital cardiac arrest. The main study outcome was the rate of adjusted survival to hospital discharge or 30 days. Secondary outcomes included unadjusted survival to hospital discharge and favourable neurological outcome.

RESULTS

A total of 28 studies were included, involving 1,931,123 patients. Female were older than male, their cardiac arrests were less likely to be witnessed and less likely to present with a shockable rhythm. Unadjusted analysis showed that females had a lower likelihood of survival than males (OR 0.68 [0.62-0.74], I2 = 97%). After adjustment, no significant difference was identified between male and female in survival at hospital discharge/30 days (OR 1.01 [0.93-1.11], I2 = 87%). Data showed that male had a significantly higher likelihood of favorable neurological outcome in unadjusted analysis but this trend disappeared after adjustment. Both the primary outcome (adjusted for several variables) and the secondary outcomes were associated with substantial heterogeneity. The variables examined using meta-regression, subgroup and sensitivity analyses (i.e., study type, location, years, population, quality of adjustment, risk of bias) did not reduce heterogeneity.

CONCLUSIONS

The adjusted rate of survival to hospital discharge/30 days was similar for male and female despite an initial seeming survival advantage for male. The validity of this finding is limited by substantial heterogeneity despite in-depth investigation of its causes, which raises concerns regarding latent inequalities in some reports nonetheless. Further study on this topic may require inclusion of factors not reported in the Utstein template and in-depth analysis of decision-making processes.

Sex Differences in Mortality of ICU Patients According to Diagnosis-related Sex Balance

Rationale: Women have worse outcomes than men in several conditions more common in men, including cardiac surgery and burns. Objectives: To describe the relationship between sex balance within each diagnostic group of ICU admissions, defined as the percentage of patients who were women, and hospital mortality of women compared with men with that same diagnosis. Methods: We studied ICU patients in the Australian and New Zealand Intensive Care Society's Adult Patient Database (2011-2020). We performed mixed effects logistic regression for hospital mortality adjusted for sex, illness severity, ICU lead time, admission year, and hospital site. We compared sex balance with the adjusted hospital mortality of women compared with men for each diagnosis using weighted linear regression. Measurements and Main Results: There were 1,450,782 admissions (42.1% women), with no difference in the adjusted hospital mortality of women compared with men overall (odds ratio, 0.99; 99% confidence interval [CI], 0.97 to 1). As the percentage of women within each diagnosis increased, the adjusted mortality of women compared with men with that same diagnosis decreased (regression coefficient, -0.015; 99% CI; -0.020 to -0.011; P < 0.001), and the illness severity of women compared with men at ICU admission decreased (regression coefficient, -0.0026; 99% CI, -0.0035 to -0.0018; P < 0.001). Conclusions: Sex balance in diagnostic groups was inversely associated with both the adjusted mortality and illness severity of women compared with men. In diagnoses with relatively few women, women were more likely than men to die. In diagnoses with fewer men, men were more likely than women to die.

Racial/ethnic and gender disparities of the impact of the COVID-19 pandemic in out-of-hospital cardiac arrest (OHCA) in Texas

INTRODUCTION

Prior research shows a greater disease burden, lower BCPR rates, and worse outcomes in Black and Hispanic patients after OHCA. Female OHCA patients have lower rates of BCPR compared to men and other survival outcomes vary. The influence of the COVID-19 pandemic on OHCA incidence and outcomes in different health disparity populations is unknown.

METHODS

We used data from the Texas Cardiac Arrest Registry to Enhance Survival (CARES). We determined the association of both prehospital characteristics and survival outcomes with the pandemic period in each study group through Pearson's χ2 test or Fisher's exact tests. We created mixed multivariable logistic regression models to compare odds of cardiac arrest care and outcomes between 2019 and 2020 for the study groups.

RESULTS

Black OHCA patients (aOR = 0.73; 95% CI: 0.65 - 0.82) had significantly lower odds of BCPR compared to White OHCA patients, were less likely to achieve ROSC (aOR = 0.86; 95% CI: 0.74 - 0.99) or have a good CPC score (aOR = 0.47; 95% CI: 0.29 - 0.75). Compared to White patients with OHCA, Hispanic persons were less likely to have a field TOR (aOR = 0.86; 95% CI: 0.75 - 0.99) or receive BCPR (aOR = 0.78; 95% CI: 0.69 - 0.87). Female OHCA patients had higher odds of surviving to hospital admission compared to males (aOR = 1.29; 95% CI: 1.15 - 1.44).

CONCLUSION

Many OHCA outcomes worsened for Black and Hispanic patients. While some aspects of care worsened for women, their odds of survival improved compared to males.

Sex-Based Differences in 30-Day Readmissions After Cardiac Arrest: Analysis of the Nationwide Readmissions Database

Background There are limited data on the sex-based differences in the outcome of readmission after cardiac arrest. Methods and Results Using the Nationwide Readmissions Database, we analyzed patients hospitalized with cardiac arrest between 2010 and 2015. Based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes, we identified comorbidities, therapeutic interventions, and outcomes. Multivariable logistic regression was performed to assess the independent association between sex and outcomes. Of 835 894 patients, 44.4% (n=371 455) were women, of whom 80.7% presented with pulseless electrical activity (PEA)/asystole. Women primarily presented with PEA/asystole (80.7% versus 72.4%) and had a greater comorbidity burden than men, as assessed using the Elixhauser Comorbidity Score. Thirty-day readmission rates were higher in women than men in both PEA/asystole (20.8% versus 19.6%) and ventricular tachycardia/ventricular fibrillation arrests (19.4% versus 17.1%). Among ventricular tachycardia/ventricular fibrillation arrest survivors, women were more likely than men to be readmitted because of noncardiac causes, predominantly infectious, respiratory, and gastrointestinal illnesses. Among PEA/asystole survivors, women were at higher risk for all-cause (adjusted odds ratio [aOR], 1.07; [95% CI, 1.03-1.11]), cardiac-cause (aOR, 1.15; [95% CI, 1.06-1.25]), and noncardiac-cause (aOR, 1.13; [95% CI, 1.04-1.22]) readmission. During the index hospitalization, women were less likely than men to receive therapeutic procedures, including coronary angiography and targeted therapeutic management. While the crude case fatality rate was higher in women, in both ventricular tachycardia/ventricular fibrillation (51.8% versus 47.4%) and PEA/asystole (69.3% versus 68.5%) arrests, sex was not independently associated with increased crude case fatality after adjusting for differences in baseline characteristics. Conclusions Women are at increased risk of readmission following cardiac arrest, independent of comorbidities and therapeutic interventions.

The association between CPR quality of In-hospital resuscitation and sex: A hypothesis generating, prospective observational study

Introduction

The relationship between sex and cardiopulmonary resuscitation (CPR) outcomes remains unclear. Particularly, questions remain regarding the potential contribution of unmeasured confounders. We aimed to examine the differences in the quality of chest compression delivered to men and women.

Methods

Prospective study of observational data recorded during consecutive resuscitations occurring in a single tertiary center (Feb-1-2015 to Dec-31-2018) with real-time follow-up to hospital discharge. The studied variables included time in CPR, no-flow-time and fraction, compression rate and depth and release velocity. The primary study endpoint was the unadjusted association between patient sex and the chest compression quality (depth and rate). The secondary endpoint was the association between the various components of chest compression quality, sex, and survival to hospital discharge/neurologically intact survival.

Results

Overall 260 in-hospital resuscitations (57.7% male patients) were included. Among these 100 (38.5%) achieved return of spontaneous circulation (ROSC) and 35 (13.5%) survived to hospital discharge. Female patients were significantly older. Ischemic heart disease and ventricular arrhythmias were more prevalent among males. Compression depth was greater in female vs male patients (54.9 ± 11.3 vs 51.7 ± 10.9 mm; p = 0.024). Other CPR quality-metrics were similar. The rates of ROSC, survival to hospital discharge and neurologically intact survival did not differ between males and females. Univariate analysis revealed no association between sex, quality metrics and outcomes.

Discussion

Women received deeper chest compressions during in-hospital CPR. Our findings require corroboration in larger cohorts but nonetheless underscore the need to maintain high-quality CPR in all patients using real-time feedback devices. Future studies should also include data on ventilation rates and volumes which may contribute to survival outcomes.

Factors influencing prehospital physicians' decisions to initiate advanced resuscitation for asystolic out-of-hospital cardiac arrest patients

BACKGROUND

The decision to initiate or continue advanced life support (ALS) in out-of-hospital cardiac arrest (OHCA) could be difficult due to the lack of information and contextual elements, especially in non-shockable rhythms. This study aims to explore factors associated with clinicians' decision to initiate or continue ALS and the conditions associated with higher variability in asystolic patients.

METHODS

This retrospective observational study enrolled 2653 asystolic patients on whom either ALS was attempted or not by the emergency medical services (EMS) physician. A multivariable logistic regression analysis was performed to find the factors associated with the decision to access ALS. A subgroup analysis was performed on patients with a predicted probability of ALS between 35% and 65%. The single physicians' behaviour was compared to that predicted by the model taking into account the entire agency.

RESULTS

Age, location of event, bystander CPR and EMS-witnessed event were independent factors influencing physicians' choices about ALS. Non-medical OHCA, younger patients, less experienced physicians, presence of breath activity at the emergency call and a longer time for ALS arrival were more frequent among cases with an expected higher variability in behaviours with ALS. Significant variability was detected between physicians.

CONCLUSIONS

Significant inter-physician variability in access to ALS could be present within the same EMS, especially among less experienced physicians, non-medical OHCA and in presence of signs of life during emergency call. This arbitrariness has been observed and should be properly addressed by EMS team members as it raises ethical issues regarding the disparity in treatment.

Association between sex and survival after non-traumatic out of hospital cardiac arrest: A systematic review and meta-analysis

BACKGROUND

Existing studies have shown conflicting results regarding the relationship of sex with survival after out of hospital cardiac arrest (OHCA). This systematic review evaluates the association of female sex with survival to discharge and survival to 30 days after non-traumatic OHCA.

METHODS

We searched Medline, Embase, CINAHL, Web of Science, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews from inception through June 2021 for studies evaluating female sex as a predictor of survival in adult patients with non-traumatic cardiac arrest. Random-effects inverse variance meta-analyses were performed to calculate pooled odds ratios (ORs) with 95% confidence intervals (CI). The GRADE approach was used to assess evidence quality.

RESULTS

Thirty studies including 1,068,788 patients had female proportion of 41%. There was no association for female sex with survival to discharge (OR 1.03, 95% CI 0.95-1.12; I²=89%). Subgroup analysis of low risk of bias studies demonstrated increased survival to discharge for female sex (OR 1.20, 95% CI 1.18-1.23; I²=0%) and with high certainty, the absolute increase in survival was 2.2% (95% CI 0.1%-3.6%). Female sex was not associated with survival to 30 days post-OHCA (OR 1.02, 95% CI 0.92-1.14; I²=79%).

CONCLUSIONS

In adult patients experiencing OHCA, with high certainty in the evidence from studies with low risk of bias, female sex had a small absolute difference for the outcome survival to discharge and no difference in survival at 30 days. Future models that aim to stratify risk of survival post-OHCA should focus on sex-specific factors as opposed to sex as an isolated prognostic factor.

Health inequities in out-of-hospital cardiac arrest

PURPOSE OF REVIEW

Out-of-hospital cardiac arrest (OHCA) is a time-critical emergency in which a rapid response following the chain of survival is crucial to save life. Disparities in care can occur at each link in this pathway and hence produce health inequities. This review summarises the health inequities that exist for OHCA patients and suggests how they may be addressed.

RECENT FINDINGS

There is international evidence that the incidence of OHCA is increased with increasing deprivation and in ethnic minorities. These groups have lower rates of bystander CPR and bystander-initiated defibrillation, which may be due to barriers in accessing cardiopulmonary resuscitation training, provision of public access defibrillators, and language barriers with emergency call handlers. There are also disparities in the ambulance response and in-hospital care following resuscitation. These disadvantaged communities have poorer survival following OHCA.

SUMMARY

OHCA disproportionately affects deprived communities and ethnic minorities. These groups experience disparities in care throughout the chain of survival and this appears to translate into poorer outcomes. Addressing these inequities will require coordinated action that engages with disadvantaged communities.

Sex Differences in Incidence and Outcome of Out-of-Hospital Cardiac Arrest Within a Local Health Network

Introduction

Sex and gender differences in presentation and characteristics of out-of-hospital cardiac arrest (OHCA) are established in cohorts with presumed cardiac aetiology but not non-cardiac etiology. This study investigated the effect of sex on incidence and outcome of OHCA according to presumed and adjudicated aetiology within a local health network.

Methods

Population-based observational cohort study of emergency medical services (EMS) attended OHCAs within an Australian local health network. Cases identified from an EMS registry between 2012-2016 were linked to a hospital registry. Age-standardised incidence and baseline characteristics were stratified by sex for EMS-treated OHCA, non-EMS witnessed presumed cardiac and obvious non-cardiac sub-cohorts, and hospitalised cases. Logistic regression was used to explore the primary outcome of survival to hospital discharge.

Results

We identified 2,024 EMS-attended and 780 EMS-treated OHCAs. The non-EMS witnessed sub-cohorts comprised 504 presumed cardiac and 168 obvious non-cardiac OHCAs. Adjudicated aetiology was recorded in 123 hospitalised cases. Age-standardised incidence for women was almost half that of men across all groups. Across cohorts, women were generally older and arrested with a non-shockable initial rhythm in an area of low socioeconomic status. There was no sex difference in the primary outcome for the main EMS-treated cohort or in the non-cardiac sub-cohorts. The sex difference in outcome in the presumed cardiac sub-cohort was not present after multivariable adjustment.

Conclusions

There are sex differences in incidence and outcome of EMS-treated OHCA that appear to be driven by differences in susceptibility to cardiac arrhythmias and underlying etiology, rather than treatment delays or disparities.

Postresuscitation care and prognostication after cardiac arrest-Does sex matter?

Background

There are conflicting results concerning sex-specific differences in the post-cardiac arrest period. We investigated the sex distribution of patients after successful cardiopulmonary resuscitation (CPR), differences in treatment, complications, outcome and sex-specific performance of biomarkers for prognostication of neurological outcome.

Methods

Prospective observational study including cardiac-arrest (CA) patients treated with mild therapeutic hypothermia (MTH) at 33 °C for 24 h or normothermia. We investigated common complications including pneumonia and acute kidney injury (AKI) and neuron-specific enolase, secretoneurin and tau protein as biomarkers of neurological outcome, which was assessed with the cerebral performance categories score at hospital discharge.

Results

Out of 134 patients 26% were female. Women were significantly older (73 years, interquartile range (IQR) 56–79 years vs. 62 years, IQR 53–70 years; p = 0.038), whereas men showed a significantly higher rate of pneumonia (29% vs. 6%; p = 0.004) and a trend towards higher rates of AKI (62% vs. 45%; p = 0.091). Frequency of MTH treatment was not significantly different (48% vs. 31%; p = 0.081). Female sex was not associated with neurological outcome in multivariable analysis (p = 0.524). There was no significant interaction of sex with prognostication of neurological outcome at 24, 48 and 72 h after CPR. At the respective time intervals p_interaction for neuron-specific enolase was 0.524, 0.221 and 0.519, for secretoneurin 0.893, 0.573 and 0.545 and for tau protein 0.270, 0.635, and 0.110.

Conclusion

The proportion of female patients was low. Women presented with higher age but had fewer complications during the post-CA period. Female sex was not associated with better neurological outcome. The performance of biomarkers is not affected by sex.

Supplementary Information

The online version of this article (10.1007/s00508-022-02026-x) contains supplementary material, which is available to authorized users.

Incidence, characteristics and outcomes of out-of-hospital cardiac arrests in patients with psychiatric illness: A systematic review

Aim

To conduct a systematic literature review of the existing evidence on incidence, characteristics and outcomes after out-of-hospital cardiac arrest (OHCA) in patients with psychiatric illness.

Methods

We searched Embase, Medline, PsycINFO and Web of Science using a comprehensive electronic search strategy to identify observational studies reporting on OHCA incidence, characteristics or outcomes by psychiatric illness status. One reviewer screened all titles and abstracts, and a second reviewer screened a random 10%. Two reviewers independently performed data extraction and quality assessment.

Results

Our search retrieved 11,380 studies, 10 of which met our inclusion criteria (8 retrospective cohort studies and two nested case-control studies). Three studies focused on depression, whilst seven included various psychiatric conditions. Among patients with an OHCA, those with psychiatric illness (compared to those without) were more likely to have: an arrest in a private location; an unwitnessed arrest; more comorbidities; less bystander cardiopulmonary resuscitation; and an initial non-shockable rhythm. Two studies reported on OHCA incidence proportion and two reported on survival, showing higher risk, but lower survival, in patients with psychiatric illness.

Conclusion

Psychiatric illness in relation to OHCA incidence and outcomes has rarely been studied and only a handful of studies have reported on OHCA characteristics, highlighting the need for further research in this area. The scant existing literature suggests that psychiatric illness may be associated with higher risks of OHCA, unfavourable characteristics and poorer survival. Future studies should further investigate these links and the role of potential contributory factors such as socioeconomic status and comorbidities.

Sex Differences in Treatment of Adult Intensive Care Patients: A Systematic Review and Meta-Analysis

OBJECTIVES

To evaluate and synthesize the available literature on sex differences in the treatment of adult ICU patients.

DATA SOURCES

MEDLINE and EMBASE.

STUDY SELECTION

Two reviewers independently screened publications to identify observational studies of adult ICU patients that explicitly examined the association between sex and ICU treatment-specifically, mechanical ventilation, renal replacement therapy, and length of stay.

DATA EXTRACTION

We extracted data independently and in duplicate: mean age, illness severity, use of mechanical ventilation and renal replacement therapy, and length of stay in ICU and hospital. We assessed risk of bias using the Newcastle-Ottawa Scale. We used a DerSimonian-Laird random-effects model to calculate pooled odds ratios (ORs) and mean differences between women and men.

DATA SYNTHESIS

We screened 4,098 publications, identifying 21 eligible studies with 545,538 participants (42.7% women). The study populations ranged from 246 to 261,255 participants (median 4,420). Most studies (76.2%) were at high risk of bias in at least one domain, most commonly representativeness or comparability. Women were less likely than men to receive invasive mechanical ventilation (OR, 0.83; 95% CI, 0.77-0.89; I2 = 90.4%) or renal replacement therapy (OR, 0.79; 95% CI, 0.70-0.90; I2 = 76.2%). ICU length of stay was shorter in women than men (mean difference, -0.24 d; 95% CI, -0.37 to -0.12; I2 = 89.9%). These findings persisted in meta-analysis of data adjusted for illness severity and other confounders and also in sensitivity analysis excluding studies at high risk of bias. There was no significant sex difference in duration of mechanical ventilation or hospital length of stay.

CONCLUSIONS

Women were less likely than men to receive mechanical ventilation or renal replacement therapy and had shorter ICU length of stay than men. There is substantial heterogeneity and risk of bias in the literature; however, these findings persisted in sensitivity analyses.

Long-term outcomes after out-of-hospital cardiac arrest: a systematic review and meta-analysis

AIMS

Long term outcomes after out-of-hospital cardiac arrest (OHCA) are not well understood. This study aimed to evaluate the long-term (1-year and beyond) survival outcomes, including overall survival and survival with favorable neurological status and the quality-of-life (QOL) outcomes, among patients who survived the initial OHCA event (30 days or till hospital discharge).

METHODS

Embase, Medline and PubMed were searched for primary studies (randomized controlled trials, cohort and cross-sectional studies) which reported the long-term survival outcomes of OHCA patients. Data abstraction and quality assessment was conducted, and survival at predetermined timepoints were assessed via single-arm meta-analyses of proportions, using generalized linear mixed models. Comparative meta-analyses were conducted using the Mantel-Haenszel Risk Ratio (RR) estimates, using the DerSimonian and Laird model.

RESULTS

67 studies were included, and among patients that survived to hospital discharge or 30-days, 77.3% (CI=71.2-82.4), 69.6% (CI=54.5-70.3), 62.7% (CI=54.5-70.3), 46.5% (CI=32.0-61.6), and 20.8% (CI=7.8-44.9) survived to 1-, 3-, 5-, 10- and 15-years respectively. Compared to Asia, the probability of 1-year survival was greater in Europe (RR=2.1, CI=1.8-2.3), North America (RR=2.0, CI=1.7-2.2) and Oceania (RR=1.9,CI=1.6-2.1). Males had a higher 1-year survival (RR:1.41, CI=1.25-1.59), and patients with initial shockable rhythm had improved 1-year (RR=3.07, CI=1.78-5.30) and 3-year survival (RR=1.45, CI=1.19-1.77). OHCA occurring in residential locations had worse 1-year survival (RR=0.42, CI=0.25-0.73).

CONCLUSION

Our study found that up to 20.8% of OHCA patients survived to 15-years, and survival was lower in Asia compared to the other regions. Further analysis on the differences in survival between the regions are needed to direct future long-term treatment of OHCA patients.

Women receive less targeted temperature management than men following out-of-hospital cardiac arrest due to early care limitations - A study from the CARES Investigators

BACKGROUND

Women experience worse neurological outcomes following out-of-hospital cardiac arrest (OHCA). It is unknown whether sex disparities exist in the use of targeted temperature management (TTM), a standard of care treatment to improve neurological outcomes.

METHODS

We performed a retrospective study of prospectively collected patients who survived to hospital admission following OHCA from the Cardiac Arrest Registry to Enhance Survival from 2013 through 2019. We compared receipt of TTM by sex in a mixed-effects model adjusted for patient, arrest, neighborhood, and hospital factors, with the admitting hospital modeled as a random intercept.

RESULTS

Among 123,419 patients, women had lower rates of shockable rhythms (24.4 % vs. 39.2%, P < .001) and lower rates of presumed cardiac aetiologies for arrest (74.3% vs. 81.1%, P < .001). Despite receiving a similar rate of TTM in the field (12.1% vs. 12.6%, P = .02), women received less TTM than men upon admission to the hospital (41.6% vs. 46.4%, P < .001). In an adjusted mixed-effects model, women were less likely than men to receive TTM (Odds Ratio 0.91, 95% Confidence Interval 0.89 to 0.94). Among the 27,729 patients with data indicating the reason for not using TTM, a higher percentage of women did not receive TTM due to Do-Not-Resuscitate orders/family requests (15.1% vs. 11.4%, p < .001) and non-shockable rhythms (11.1% vs. 8.4%, p < .001).

CONCLUSIONS

We found that women received less TTM than men, likely due to early care limitations and a preponderance of non-shockable rhythms.

Do Women Have a Higher Mortality Risk Than Men following ICU Admission after Out-of-Hospital Cardiac Arrest? A Retrospective Cohort Analysis

Purpose: previous studies showed that women have a higher mortality risk than men after out-of-hospital cardiac arrest (OHCA). This sex difference may disappear after adjustment for cardiac arrest characteristics. Most studies also included patients who were not admitted to the intensive care unit (ICU). We analyzed whether sex impacts the mortality of ICU-admitted OHCA patients. Methods: a retrospective cohort analysis of 1240 OHCA patients admitted to the ICU (310 women, 25%, Age_Median 64.0 (IQR 53.8–73.0)) at an academic hospital in the Netherlands between 1 January 2007 and 31 December 2018. The primary outcome was 90-day mortality; the secondary outcome was a favorable cerebral performance category (CPC) score at ICU discharge and ICU length of stay (ICU LOS). Results: we found no association between sex and 90-day mortality (hazard ratio (HR) 0.867; 95% confidence interval (95% CI) 0.678–1.108) after adjusting for relevant cardiac arrest characteristics. Similarly, we found no difference for favorable CPC score (OR 1.117; 95% CI 0.777–1.608) or ICU LOS between sexes (Beta 0.428; 95% CI −0.442 to 1.298). Conclusions: after adjusting for cardiac arrest characteristics, we found no difference between women and men with respect to 90-day mortality, ICU LOS, and CPC score.

Interaction between gender and post resuscitation interventions on neurological outcome in an asphyxial rat model of cardiac arrest

PURPOSE

Previous clinical studies have suggested an effect of gender on outcome after out-of-hospital cardiac arrest, but the results are conflicting and there is no uniform agreement regarding gender differences in survival and prognosis. The present study was aimed to investigate the interaction between gender and post resuscitation interventions on neurological outcome in an asphyxial rat model of cardiac arrest.

METHODS

Asphyxia was induced by blocking the endotracheal tube in 120 adult Sprague-Dawley rats (60 males and 60 females) at the same age. Cardiopulmonary resuscitation (CPR) was started after 5 min of untreated cardiac arrest. Animals were randomized into one of the three post resuscitation care intervention groups (n = 40, 20 males) immediately after resuscitation: (1) normothermic control (NC): ventilated with 2% N2/98% O2 for 1 h under normothermia; (2) targeted temperature management (TTM): ventilated with 2% N2/98% O2 for 1 h under hypothermia; (3) hydrogen inhalation (HI): ventilated with 2% H2/98% O2 for 1 h under normothermia. Physiological variables were recorded during the 5 h post resuscitation monitoring period. Neurological deficit score (NDS) and accumulative survival were used to assess 96 h outcomes. Mutual independence analysis and Mantel-Haenszel stratified analysis were used to explore the associations among gender, intervention and survival.

RESULTS

The body weights of female rats were significantly lighter than males, but CPR characteristics did not differ between genders. Compared with male rats, females had significantly lower mean arterial pressure, longer onset time of the electroencephalogram (EEG) burst and time to normal EEG trace (TTNT) in the NC group; relatively longer TTNT in the TTM group; and substantially longer TTNT, lower NDSs, and higher survival in the HI group. Mutual independence analysis revealed that both gender and intervention were associated with neurological outcome. Mantel-Haenszel stratified analysis demonstrated that female rats had significantly higher survival rate than males when adjusted for the confounder intervention.

CONCLUSION

In this rat model cardiac arrest and CPR, gender did not affect resuscitation but associated with neurological outcome. The superiority of female rats in neurological recovery was affected by post resuscitation interventions and female rats were more likely to benefit from hydrogen therapy.

Sex differences in illness severity and mortality among adult intensive care patients: A systematic review and meta-analysis

PURPOSE

To investigate the association between sex and illness severity and mortality of ICU patients.

METHODS

We performed systematic searches of MEDLINE and EMBASE for observational studies of adult ICU patients that explicitly examined the association between sex and illness severity or mortality. We used a random effects model to calculate standardised mean differences in illness severity scores and pooled odds ratios for mortality of women compared to men.

RESULTS

We identified 21 studies with 505,138 participants in total (43.1% women). There was substantial heterogeneity among studies. Only two studies were at low risk of bias overall. At ICU admission, there was a pattern of higher illness severity scores among women (standardised mean difference 0.04, 95% CI -0.01-0.09). Women had higher risk-adjusted mortality than men at ICU discharge (OR 1.25 95% CI 1.03-1.50) and 1 year (OR 1.08, 95% CI 1.02-1.13), however this finding was not robust to sensitivity analysis.

CONCLUSIONS

Women tend to have higher illness severity scores at ICU admission. Women also appear to have higher risk-adjusted mortality than men at ICU discharge and at 1 year. Given the heterogeneity and risk of bias in the existing literature, additional studies are needed to confirm or refute these findings.