Socioeconomic status and prediction of ventricular fibrillation survival

Differences in Out-of-Hospital Cardiac Arrest Outcomes Among 5 Racial/Ethnic Groups

OBJECTIVE

Out-of-hospital cardiac arrest (OHCA) is a major health problem and one of the leading causes of death in adults older than 40. Multiple prior studies have demonstrated survival disparities based on race/ethnicity, but most of these focus on a single racial/ethnic group. This study evaluated OHCA variables and outcomes among on 5 racial/ethnic groups.

METHODS

This is a retrospective review of data for adult patients in the Cardiac Arrest Registry to Enhance Survival (CARES) from 3 racially diverse urban counties in the San Francisco Bay Area from May 2009 to October 2021. Stratifying by 5 racial/ethnic groups, we evaluated patient survival outcomes based on patient demographics, emergency medical services response location, cardiac arrest characteristics, and hospital interventions. Adjusted risk ratios were calculated for survival to hospital discharge, controlling for sex, age, response locations, median income of response location, arrest witness, shockable rhythm, and bystander cardiopulmonary resuscitation as well as clustering by census tract.

RESULTS

There were 10,757 patient entries analyzed: 42% White, 24% Black, 18% Asian, 9.3% Hispanic, 6.0% Pacific Islander, 0.7% American Indian/Alaska Native, and 0.1% multiple races selected; however, only the first 5 racial/ethnic groups had sufficient numbers for comparison. The adjusted risk ratio for survival to hospital discharge was lower among the 4 racial/ethnic groups compared with the White reference group: Black (0.79, p = 0.003), Asian (0.78 p = 0.004), Hispanic (0.79, p = 0.018), and Pacific Islander (0.78, p = 0.041) groups. The risk difference for positive neurologic outcome was also lower among all 4 racial/ethnic groups compared with the White reference group.

CONCLUSIONS

The Black, Asian, Hispanic, and Pacific Islander groups were less likely to survive to hospital discharge from OHCA when compared with the White reference group. No variables were associated with decreased survival across any of these 4 groups.

Variation in the Use of Targeted Temperature Management for Cardiac Arrest

Targeted temperature management (TTM) is recommended for patients who do not respond after return of spontaneous circulation after cardiac arrest. However, the degree to which patients with cardiac arrest have access to this therapy on a national level is not known. Understanding hospital- and patient-level factors associated with receipt of TTM could inform interventions to improve access to this treatment among appropriate patients. Therefore, we performed a retrospective analysis using National Inpatient Sample data from 2016 to 2019. We used International Classification of Diseases, Tenth Edition diagnosis and procedure codes to identify adult patients with in-hospital and out-of-hospital cardiac arrest and receipt of TTM. We evaluated patient and hospital factors associated with receiving TTM. We identified 478,419 patients with cardiac arrest. Of those, 4,088 (0.85%) received TTM. Hospital use of TTM was driven by large, nonprofit, urban, teaching hospitals, with less use at other hospital types. There was significant regional variation in TTM capabilities, with the proportion of hospitals providing TTM ranging from >21% in the Mid-Atlantic region to <11% in the East and West South Central and Mountain regions. At the patient level, age >74 years (odds ratio [OR] 0.54, p <0.001), female gender (OR 0.89, p >0.001), and Hispanic ethnicity (OR 0.74, p <0.001) were all associated with decreased odds of receiving TTM. Patients with Medicare (OR 0.75, p <0.001) and Medicaid (OR 0.89, p = 0.027) were less likely than patients with private insurance to receive TTM. Part of these differences was driven by inequitable access to TTM-capable hospitals. In conclusion, TTM is rarely used after cardiac arrest. Hospital use of TTM is predominately limited to a subset of academic hospitals with substantial regional variation. Older age, female gender, Hispanic ethnicity, and Medicare or Medicaid insurance are all associated with a decreased likelihood of receiving TTM.

The effect of ethnicity and socioeconomic status on outcomes after resuscitated out-of-hospital cardiac arrest - Findings from a tertiary centre in South London

Background

Out-of-hospital cardiac arrest is a common cause of morbidity and mortality, and ethnic variation in outcomes is recognised. We investigated ethnic and socioeconomic differences in arrest circumstances, rates of coronary artery disease, treatment, and outcomes in resuscitated OOHCA.

Methods

Patients with resuscitated OOHCA of suspected cardiac aetiology were included in the King's Out-of-Hospital Cardiac Arrest Registry between 1-May-2012 and 31-December-2020.

Results

Of 526 patients (median age 62.0 years, IQR 21.1, 74.1% male), 414 patients (78.7%) were White, 35 (6.7%) were Asian, and 77 (14.6%) were Black. Black patients had more co-existent hypertension (p = 0.007) and cardiomyopathy (p = 0.003), but less prior coronary revascularisation (p = 0.026) compared with White/Asian patients. There were no ethnic differences in location, witnesses, or bystander CPR, but Black patients had more non-shockable rhythms (p < 0.001). Black patients received less immediate coronary angiography (p < 0.001) and percutaneous coronary intervention (p < 0.001) but had lower rates of CAD (p = 0.004) than White/Asian patients. All-cause mortality at 12 months was highest amongst Black patients, followed by Asian and then White patients (57.1% vs 48.6% vs 41.3%, p = 0.032). In Black patients, excess mortality was driven by higher rates of multi-organ dysfunction but lower cardiac death than White/Asian patients, with cardiac death highest amongst Asian patients (p = 0.009). Socioeconomic status had no effect on mortality, and in a multivariable logistic regression, age, location, witnesses, and Black compared to White ethnicity were independent predictors of mortality, whilst social deprivation was not.

Conclusion

In this single-centre study, Black patients had higher mortality after resuscitated OOHCA than White/Asian patients. This may be in part due to differing underlying aetiology rather than differences in arrest circumstances or social deprivation.

Are there socioeconomic disparities in geographic accessibility to community first responders to out-of-hospital cardiac arrest in Ireland?

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide. Without appropriate early resuscitation interventions, the prospect of survival is limited. This means that an effective community response is a critical enabler of increasing the number of people who survive. However, while OHCA incidence is higher in more deprived areas, propensity to volunteer is, in general, associated with higher socioeconomic status. In this context, we consider whether there are socioeconomic disparities in geographic accessibility to volunteer community first responders (CFRs) in Ireland, where CFR groups have developed organically and communities self-select to participate. We use geographic information systems and propensity score matching to generate a set of control areas with which to compare established CFR catchment areas. Differences between CFRs and controls in terms of the distribution of catchment deprivation and social fragmentation scores are assessed using two-sided Kolmogorov-Smirnov tests. Overall we find that while CFR schemes are centred in more deprived and socially fragmented areas, beyond a catchment of 4 min there is no evidence of differences in area-level deprivation or social fragmentation. Our findings show that self-selection as a model of CFR recruitment does not lead to more deprived areas being disadvantaged in terms of access to CFR schemes. This means that community-led health interventions can develop to the benefit of community members across the socioeconomic spectrum and may be relevant for other countries and jurisdictions looking to support similar models within communities.

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Out-of-hospital cardiac arrest (OHCA) is a major cause of unexpected death.

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OHCA is more prevalent in deprived areas and community response is key for survival.

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Irish community first responders (CFRs) self-select to participate in CFR schemes.

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We consider if there are socioeconomic disparities in geographic access to CFRs.

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Self-selection does not result in deprived areas having worse access to CFR schemes.

Treatment and survival following in-hospital cardiac arrest: does patient ethnicity matter?

AIMS 

Previous research on racial/ethnic disparities in relation to cardiac arrest has mainly focused on black vs. white disparities in the USA. The great majority of these studies concerns out-of-hospital cardiac arrest (OHCA). The current nationwide registry study aims to explore whether there are ethnic differences in treatment and survival following in-hospital cardiac arrest (IHCA), examining possible disparities towards Middle Eastern and African minorities in a European context.

METHODS AND RESULTS

In this retrospective registry study, 24 217 patients from the IHCA part of the Swedish Registry of Cardiopulmonary Resuscitation were included. Data on patient ethnicity were obtained from Statistics Sweden. Regression analysis was performed to assess the impact of ethnicity on cardiopulmonary resuscitation (CPR) delay, CPR duration, survival immediately after CPR, and the medical team's reported satisfaction with the treatment. Middle Eastern and African patients were not treated significantly different compared to Nordic patients when controlling for hospital, year, age, sex, socioeconomic status, comorbidity, aetiology, and initial heart rhythm. Interestingly, we find that Middle Eastern patients were more likely to survive than Nordic patients (odds ratio = 1.52).

CONCLUSION

Overall, hospital staff do not appear to treat IHCA patients differently based on their ethnicity. Nevertheless, Middle Eastern patients are more likely to survive IHCA.

Discriminatory cardiac arrest care? Patients with low socioeconomic status receive delayed cardiopulmonary resuscitation and are less likely to survive an in-hospital cardiac arrest

AIMS

Individuals with low socioeconomic status (SES) face widespread prejudice in society. Whether SES disparities exist in treatment and survival following in-hospital cardiac arrest (IHCA) is unclear. The aim of the current retrospective registry study was to examine SES disparities in IHCA treatment and survival, assessing SES at the patient level, and adjusting for major demographic, clinical, and contextual factors.

METHODS AND RESULTS

In total, 24 217 IHCAs from the Swedish Register of Cardiopulmonary Resuscitation were analysed. Education and income constituted SES proxies. Controlling for age, gender, ethnicity, comorbidity, heart rhythm, aetiology, hospital, and year, primary analyses showed that high (vs. low) SES patients were significantly less likely to receive delayed cardiopulmonary resuscitation (CPR) (highly educated: OR = 0.89, and high income: OR = 0.98). Furthermore, patients with high SES were significantly more likely to survive CPR (high income: OR = 1.02), to survive to hospital discharge with good neurological outcome (highly educated: OR = 1.27; high income: OR = 1.06), and to survive to 30 days (highly educated: OR = 1.21; and high income: OR = 1.05). Secondary analyses showed that patients with high SES were also significantly more likely to receive prophylactic heart rhythm monitoring (highly educated: OR = 1.16; high income: OR = 1.02), and this seems to partially explain the observed SES differences in CPR delay.

CONCLUSION

There are clear SES differences in IHCA treatment and survival, even when controlling for major sociodemographic, clinical, and contextual factors. This suggests that patients with low SES could be subject to discrimination when suffering IHCA.

Ethnic differences in out-of-hospital cardiac arrest among Middle Eastern Arabs and North African populations living in Qatar

Aims: There are very few studies comparing epidemiology and outcomes of out-of-hospital cardiac arrest (OHCA) in different ethnic groups. Previous ethnicity studies have mostly determined OHCA differences between African American and Caucasian populations. The aim of this study was to compare epidemiology, clinical presentation, and outcomes of OHCA between the local Middle Eastern Gulf Cooperation Council (GCC) Arab and the migrant North African populations living in Qatar.Methods: This was a retrospective cohort study of Middle Eastern GCC Arabs and migrant North African patients with presumed cardiac origin OHCA resuscitated by Emergency Medical Services (EMS) in Qatar, between June 2012 and May 2015.Results: There were 285 Middle Eastern GCC Arabs and 112 North African OHCA patients enrolled during the study period. Compared with the local GCC Arabs, univariate analysis showed that the migrant North African OHCA patients were younger and had higher odds of initial shockable rhythm, pre-hospital interventions (defibrillation and amioderone), pre-hospital scene time, and decreased odds of risk factors (hypertension, respiratory disease, and diabetes) and pre-hospital response time. The survival to hospital discharge had greater odds for North African OHCA patients which did not persist after adjustment. Multivariable logistic regression showed that North Africans were associated with lower odds of diabetes (OR 0.48, 95% CI 0.25-0.91, p = 0.03), and higher odds of initial shockable rhythm (OR 2.86, 95% CI 1.30-6.33, p = 0.01) and greater scene time (OR 1.02 95% CI 1.0-1.04, p = 0.02).Conclusions: North African migrant OHCA patients were younger, had decreased risk factors and favourable OHCA rhythm and received greater ACLS interventions with shorter pre-hospital response times and longer scene times leading to better survival.

Impact of Racial and Gender Variations in Patients With Out-of-hospital Cardiac Arrest: A Nation-Wide Study

The overall incidence of Out-of-hospital Cardiac Arrest (OHCA) is decreasing worldwide due to emergency responses, but there are gender and racial differences in the incidence of OHCA, which remain under investigation. Our aim was to identify the incidence, gender, and racial disparities in patients admitted with OHCA. The National Inpatient Sample Database is one of the largest all-payer inpatient database. It was queried to identify patients 18 years or older who were hospitalized with the principal diagnosis of OHCA. There was a total of 85,988 patients who were discharged with a diagnosis classified as OHCA using the ICD-9 code for a period of 2 years. The mean age of the patients who had presented to the hospital with OHCA was 64.3 (±18.5 years). Overall, a greater number of males suffered from OHCA were compared with female population of (48,635 vs 37,366; P < 0.0001). The incidence of OHCA was higher among Caucasians as compared with African Americans (54,812, 63.8% vs 13,787, 16%; P < 0.0001). In-hospital deaths after OHCA were 43,024 (50%). But African Americans had higher mortality than Caucasians after hospitalization for OHCA (adjusted odds ratio, 1.23; 95% confidence interval, 1.18-1.26; P < 0.01). We observed significant differences in gender and racial factors in the patients who were admitted to the hospital with a diagnosis of OHCA based on an analysis of the national inpatient database.

Socioeconomic disparities in prehospital cardiac arrest outcomes: An analysis of the NEMSIS database

BACKGROUND

Socioeconomic disparities are engrained in the US healthcare system and may extend to the prehospital cardiac arrest setting where mortality is high.

METHODS

Using the National Emergency Medical Services Information System (NEMSIS) database, 150,003 cases were analyzed comparing socioeconomic status and cardiac arrest outcomes. Cardiac arrest outcomes were measured by the percent of cases that achieved return of spontaneous circulation (ROSC) and the percent of cases in which ROSC occurred in the Emergency Department (ED) as opposed to a prehospital setting which was a proxy for the length of time spent in cardiac arrest. Chi-square tests checked for statistical significance and effect size was measured using Pearson's r values and linear regression coefficients.

RESULTS

Comparing neighborhood poverty level and the percent of cardiac arrest cases that achieved ROSC resulted in a Pearson's r value of 0.9424 (R² = 0.8881, p < 0.005) and a linear regression coefficient of 2.088 (p < 0.05, R² = 0.8881, 95% CI [1.059, 3.117]) meaning for every interval increase in poverty, the chance of an individual in cardiac arrest achieving ROSC decreases 2.09%. Comparing neighborhood poverty level and the percent of ROSC cases that occurred in the ED yielded a Pearson's r value of 0.9005 (R² = 0.8109, p < 0.05) and a linear regression coefficient of 0.7701 (p < 0.05, R² = 0.8109, 95% CI [0.254, 1.286]) meaning for every interval increase in poverty, the chance that ROSC is delayed increases 0.77%.

CONCLUSIONS

Low income individuals in cardiac arrest have a statistically significant lower probability of achieving ROSC and a higher chance of delayed ROSC.

Women have lower chances than men to be resuscitated and survive out-of-hospital cardiac arrest

Aims

Previous studies on sex differences in out-of-hospital cardiac arrest (OHCA) had limited scope and yielded conflicting results. We aimed to provide a comprehensive overall view on sex differences in care utilization, and outcome of OHCA.

Methods and results

We performed a population-based cohort-study, analysing all emergency medical service (EMS) treated resuscitation attempts in one province of the Netherlands (2006–2012). We calculated odds ratios (ORs) for the association of sex and chance of a resuscitation attempt by EMS, shockable initial rhythm (SIR), and in-hospital treatment using logistic regression analysis. Additionally, we provided an overview of sex differences in overall survival and survival at successive stages of care, in the entire study population and in patients with SIR. We identified 5717 EMS-treated OHCAs (28.0% female). Women with OHCA were less likely than men to receive a resuscitation attempt by a bystander (67.9% vs. 72.7%; P < 0.001), even when OHCA was witnessed (69.2% vs. 73.9%; P < 0.001). Women who were resuscitated had lower odds than men for overall survival to hospital discharge [OR 0.57; 95% confidence interval (CI) 0.48–0.67; 12.5% vs. 20.1%; P < 0.001], survival from OHCA to hospital admission (OR 0.88; 95% CI 0.78–0.99; 33.6% vs. 36.6%; P = 0.033), and survival from hospital admission to discharge (OR 0.49, 95% CI 0.40–0.60; 33.1% vs. 51.7%). This was explained by a lower rate of SIR in women (33.7% vs. 52.7%; P < 0.001). After adjustment for resuscitation parameters, female sex remained independently associated with lower SIR rate.

Conclusion

In case of OHCA, women are less often resuscitated by bystanders than men. When resuscitation is attempted, women have lower survival rates at each successive stage of care. These sex gaps are likely explained by lower rate of SIR in women, which can only partly be explained by resuscitation characteristics.

Race/Ethnicity and Neighborhood Characteristics Are Associated With Bystander Cardiopulmonary Resuscitation in Pediatric Out-of-Hospital Cardiac Arrest in the United States: A Study From CARES

Background

Whether racial and neighborhood characteristics are associated with bystander cardiopulmonary resuscitation (BCPR) in pediatric out‐of‐hospital cardiac arrest (OHCA) is unknown.

Methods and Results

An analysis was conducted of CARES (Cardiac Arrest Registry to Enhance Survival) for pediatric nontraumatic OHCAs from 2013 to 2017. An index (range, 0–4) was created for each arrest based on neighborhood characteristics associated with low BCPR (>80% black; >10% unemployment; <80% high school; median income, <$50 000). The primary outcome was BCPR. BCPR occurred in 3399 of 7086 OHCAs (48%). Compared with white children, BCPR was less likely in other races/ethnicities (black: adjusted odds ratio [aOR], 0.59; 95% CI, 0.52–0.68; Hispanic: aOR, 0.78; 95% CI, 0.66–0.94; and other: aOR, 0.54; 95% CI, 0.40–0.72). Compared with arrests in neighborhoods with an index score of 0, BCPR occurred less commonly for arrests with an index score of 1 (aOR, 0.80; 95% CI, 0.70–0.91), 2 (aOR, 0.75; 95% CI, 0.65–0.86), 3 (aOR, 0.52; 95% CI, 0.45–0.61), and 4 (aOR, 0.46; 95% CI, 0.36–0.59). Black children had an incrementally lower likelihood of BCPR with increasing index score while white children had an overall similar likelihood at most scores. Black children with an index of 4 were approximately half as likely to receive BCPR compared with white children with a score of 0.

Conclusions

Racial and neighborhood characteristics are associated with BCPR in pediatric OHCA. Targeted CPR training for nonwhite, low‐education, and low‐income neighborhoods may increase BCPR and improve pediatric OHCA outcomes.

Socio-economic differences in incidence, bystander cardiopulmonary resuscitation and survival from out-of-hospital cardiac arrest: A systematic review

BACKGROUND

Individuals with a low socioeconomic status (SES) may have a greater mortality rate from out of hospital cardiac arrest (OHCA) than those with a high SES. We explored whether SES disparities in OHCA mortality manifest in the incidence of OHCA, the chance of receiving bystander cardiopulmonary resuscitation (CPR) or in the chance of surviving an OHCA. We also studied whether sex and age differences exist in such SES disparities.

METHODS

The Medline, Embase and Scopus databases were searched from 01-01-1993 until 31-01-2019. Studies utilising any study design or population were included. Studies were included if the exposure was SES of the OHCA victim or the OHCA location and the outcome was either OHCA incidence, CPR provision and/or survival rate after OHCA. Study selection and quality assessment were conducted by two reviewers independently. Descriptive data and measures of association were extracted, both in the total study population and in subgroups stratified by age and/or sex. This review was carried out following the PRISMA guidelines.

RESULTS

Overall 32 studies were included. Twelve studies reported on OHCA incidence, thirteen on bystander CPR provision and fourteen on survival. Some evidence for SES differences was found in each identified stage. In all the studies on incidence, SES was measured over the area of the OHCA victims' residence and was consistently associated with OHCA. In studies on bystander CPR, SES of the area in which the OHCA occurred was associated with bystander CPR, while evidence on individual SES was lacking. In studies on OHCA survival, SES of the victim measured at the individual level and SES of the area in which the OHCA occurred were associated, while SES of the victim, measured at the area of residence was not. Studies reporting age and sex differences in the SES trends were scarce.

CONCLUSION

SES disparities in OHCA mortality likely manifest in OHCA incidence, bystander CPR provision and survival rate after OHCA. However, there is a distinct lack of data on SES measured at the individual level and on differences within subgroups, e.g. by sex and age.

Association of Neighborhood Demographics With Out-of-Hospital Cardiac Arrest Treatment and Outcomes: Where You Live May Matter

Importance

We examined whether resuscitation care and outcomes vary by the racial composition of the neighborhood where out-of-hospital cardiac arrests (OHCAs) occur.

Objective

To evaluate the association between bystander treatments (cardiopulmonary resuscitation and automatic external defibrillation) and timing of emergency medical services personnel on OHCA outcomes according to the racial composition of the neighborhood where the OHCA event occurred.

Design, Setting, and Participants

This retrospective observational cohort study examined patients with OHCA from January 1, 2008, to December 31, 2011, using data from the Resuscitation Outcomes Consortium. Neighborhoods where OHCA occurred were classified by census tract, based on percentage of black residents: less than 25%, 25% to 50%, 51% to 75%, or more than 75%. Multilevel mixed-effects logistic regression modeling examined the association between racial composition of neighborhoods and OHCA survival, adjusting for patient, neighborhood, and treatment characteristics.

Main Outcomes and Measures

Survival to discharge, return of spontaneous circulation on emergency department arrival, and favorable neurologic status at discharge.

Results

We examined 22 816 adult patients with nontraumatic OHCA at Resuscitation Outcomes Consortium sites in the United States. The median age of patients with OHCA was 64 years (interquartile range [IQR], 51-78). Compared with patients who experienced OHCA in neighborhoods with a lower proportion of black residents, those in neighborhoods with more than 75% black residents were slightly younger, were more frequently women, had lower rates of initial shockable rhythm, and less frequently experienced OHCA in a public location. The percentage of patients with OHCA receiving bystander cardiopulmonary resuscitation or a lay automatic external defibrillation was inversely associated with the percentage of black residents in neighborhoods. Compared with OHCA in predominantly white neighborhoods (<25% black), those with OHCA in mixed to majority black neighborhoods had lower adjusted survival rates to hospital discharge (25%-50% black: odds ratio, 0.76; 95% CI, 0.61-0.93; 51%-75% black: odds ratio, 0.67; 95% CI, 0.49-0.90; >75% black: odds ratio, 0.63; 95% CI, 0.50-0.79; P < .001). There was similar mortality risk for black and white patients with OHCA in each neighborhood racial quantile. When the primary model included geographic site, there was an attenuated nonsignificant association between racial composition in a neighborhood and survival.

Conclusions and Relevance

Those with OHCA in predominantly black neighborhoods had the lowest rates of bystander cardiopulmonary resuscitation and automatic external defibrillation use and significantly lower likelihood for survival compared with predominantly white neighborhoods. Improving bystander treatments in these neighborhoods may improve cardiac arrest survival.

Ethnic and Neighborhood Socioeconomic Differences In Incidence and Survival From Out-Of-Hospital Cardiac Arrest In Singapore

Objective: We aimed to examine the association of ethnicity and socioeconomic status (SES) with Out-of-Hospital Cardiac Arrest (OHCA) incidence and 30-day survival in Singapore. Methods: We analyzed the Singapore cohort of Pan-Asia Resuscitation Outcome Study (PAROS), a multi-center, prospective OHCA registry between 2010 and 2015. The Singapore Socioeconomic Disadvantage Index (SEDI) score, obtained according to zip code, was used as surrogate for neighborhood SES. Age-adjusted OHCA incidence and Utstein survival were calculated by ethnicity and SES. Utstein survival was defined as the number of cardiac OHCA cases with initial rhythm of ventricular fibrillation witnessed by a bystander who survived 30-days or until hospital discharge. Logistic regression was used to investigate association of ethnicity with 30-day and Utstein survivals. Results: Our study population comprised 8,900 patients: 6,453 Chinese, 1,472 Malays, and 975 Indians. The overall age-adjusted incidence ratios (95% CI) for Malay/Chinese and Indian/Chinese were 1.93 (1.83-2.04) and 1.95 (1.83-2.08), respectively. The overall age-adjusted incidence ratios (95% CI) for average/low and high/low SEDI group were 1.12 (0.95-1.33) and 1.29 (1.08-1.53), respectively. Malay showed lesser Utstein survival of 8.1% compared to Chinese (14.6%) and Indian (20.4%) [p = 0.018]. Ethnicity did not reach statistical significance (p = 0.072) in forward selection model of Utstein survival, while SEDI score and category were not significant (p > 0.2 and p = 0.349). Conclusions: We found Malay and Indian communities to be at higher risks of OHCA compared to Chinese, and additionally, the Malay community is at higher risk of subsequent mortality than the Chinese and Indian communities. These disparities were not explained by neighborhood SES.

Ethnic differences in sudden cardiac arrest resuscitation

OBJECTIVE

Ethnic differences in sudden cardiac arrest resuscitation have not been fully explored and studies have yielded inconsistent results. We examined the association of ethnicity with factors affecting sudden cardiac arrest outcomes.

METHODS

Retrospective cohort study of 3551 white, 440 black and 297 Asian sudden cardiac arrest cases in Seattle and King County, Washington, USA.

RESULTS

Compared with whites, blacks and Asians were younger, had lower socioeconomic status and were more likely to have diabetes, hypertension and end-stage renal disease (all p<0.001). Blacks and Asians were less likely to have a witnessed arrest (whites 57.6%, blacks 52.1%, Asians 46.1%, p<0.001) or receive bystander cardiopulmonary resuscitation (whites 50.9%, blacks 41.4%, Asians 47.1%, p=0.001), but had shorter average emergency medical services response time (mean in minutes: whites 5.18, blacks 4.75, Asians 4.85, p<0.001). Compared with whites, blacks were more likely to be found in pulseless electrical activity (blacks 20.9% vs whites 16.6%, p<0.001), and Asians were more likely to be found in asystole (Asians 41.1% vs whites 30.0%, p<0.001). One of the strongest predictors of resuscitation outcomes was initial cardiac rhythm with 25% of ventricular fibrillation, 4% of patients with pulseless electrical activity and 1% of patients with asystole surviving to hospital discharge (adjusted OR of resuscitation in pulseless electrical activity compared with ventricular fibrillation: 0.30, 95% CI 0.24 to 0.34, p<0.001, adjusted OR of resuscitation in asystole relative to ventricular fibrillation 0.21, 95% CI 0.17 to 0.26, p<0.001). Survival to hospital discharge was similar across all three ethnicities.

CONCLUSIONS

While there were differences in some prognostic characteristics between blacks, whites and Asians, we did not detect a significant difference in survival following sudden cardiac arrest between the three ethnic groups. There was, however, an ethnic difference in presenting rhythm, with pulseless electrical activity more prevalent in blacks and asystole more prevalent in Asians.

Socioeconomic status and survival from ventricular fibrillation out-of-hospital cardiac arrest

PURPOSE

Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the United States. How individual-level socioeconomic status (SES) influences survival is uncertain.

METHODS

The investigation is a retrospective cohort study of adults who suffered OHCA and presented with a shockable rhythm in a metropolitan county from January 1, 1999-December 31, 2005. Individual-level measures of SES were obtained from vital records and surveys. SES measures included education and occupation. We used multivariable logistic regression to assess the independent association between SES measures and survival to hospital discharge.

RESULTS

Of the 1390 eligible OHCA patients, 374 (27%) survived to hospital discharge. Compared to those with less than high school diploma, the multivariable-adjusted odds ratio of survival was 1.36 (95% confidence interval [CI], 0.87-2.14) for high school graduates, 1.54 (95% CI, 0.95-2.48) for those with some college, and 1.96 (95% CI, 1.17-3.27) for those with college degrees (test for trend across the categories P < .001). We did not observe an independent association between occupation and survival.

CONCLUSIONS

Higher education was associated with greater survival after OHCA. This relationship was not explained by key demographic or clinical characteristics. A better understanding of the mechanism by which individual-level SES characteristics influence prognosis may provide opportunities to improve survival.

Does location matter? A proposed methodology to evaluate neighbourhood effects on cardiac arrest survival and bystander CPR

Background

Traditional variables used to explain survival following out-of-hospital cardiac arrest (OHCA) account for only 72% of survival, suggesting that other unknown factors may influence outcomes. Research on other diseases suggests that neighbourhood factors may partly determine health outcomes. Yet, this approach has rarely been used for OHCA. This work outlines a methodology to investigate multiple neighbourhood factors as determinants of OHCA outcomes.

Methods

A retrospective, observational cohort study design will be used. All adult non-emergency medical service witnessed OHCAs of cardiac etiology within the city of Toronto between 2006 and 2010 will be included. Event details will be extracted from the Toronto site of the Resuscitation Outcomes Consortium Epistry—Cardiac Arrest, an existing population-based dataset of consecutive OHCA patients. Geographic information systems technology will be used to assign patients to census tracts. Neighbourhood variables to be explored include the Ontario Marginalization Index (deprivation, dependency, ethnicity, and instability), crime rate, and density of family physicians. Hierarchical logistic regression analysis will be used to explore the association between neighbourhood characteristics and 1) survival-to-hospital discharge, 2) return-of-spontaneous circulation at hospital arrival, and 3) provision of bystander cardiopulmonary resuscitation (CPR). Receiver operating characteristics curves will evaluate each model’s ability to discriminate between those with and without each outcome.

Discussion

This study will determine the role of neighbourhood characteristics in OHCA and their association with clinical outcomes. The results can be used as the basis to focus on specific neighbourhoods for facilitating educational interventions, CPR awareness programs, and higher utilization of automatic defibrillation devices.

Rates of cardiopulmonary resuscitation training in the United States

IMPORTANCE

Prompt bystander cardiopulmonary resuscitation (CPR) improves the likelihood of surviving an out-of-hospital cardiac arrest. Large regional variations in survival after an out-of-hospital cardiac arrest have been noted.

OBJECTIVES

To determine whether regional variations in county-level rates of CPR training exist across the United States and the factors associated with low rates in US counties.

DESIGN, SETTING, AND PARTICIPANTS

We used a cross-sectional ecologic study design to analyze county-level rates of CPR training in all US counties from July 1, 2010, through June 30, 2011. We used CPR training data from the American Heart Association, the American Red Cross, and the Health & Safety Institute. Using multivariable logistic regression models, we examined the association of annual rates of adult CPR training of citizens by these 3 organizations (categorized as tertiles) with a county's geographic, population, and health care characteristics.

EXPOSURE

Completion of CPR training.

MAIN OUTCOME AND MEASURES

Rate of CPR training measured as CPR course completion cards distributed and CPR training products sold by the American Heart Association, persons trained in CPR by the American Red Cross, and product sales data from the Health & Safety Institute. RESULTS During the study period, 13.1 million persons in 3143 US counties received CPR training. Rates of county training ranged from 0.00% to less than 1.29% (median, 0.51%) in the lower tertile, 1.29% to 4.07% (median, 2.39%) in the middle tertile, and greater than 4.07% or greater (median, 6.81%) in the upper tertile. Counties with rates of CPR training in the lower tertile were more likely to have a higher proportion of rural areas (adjusted odds ratio, 1.12 [95% CI, 1.10-1.15] per 5-percentage point [PP] change), higher proportions of black (1.09 [1.06-1.13] per 5-PP change) and Hispanic (1.06 [1.02-1.11] per 5-PP change) residents, a lower median household income (1.18 [1.04-1.34] per $10 000 decrease), and a higher median age (1.28 [1.04-1.58] per 10-year change). Counties in the South, Midwest, and West were more likely to have rates of CPR training in the lower tertile compared with the Northeast (adjusted odds ratios, 7.78 [95% CI, 3.66-16.53], 5.56 [2.63-11.75], and 5.39 [2.48-11.72], respectively).

CONCLUSIONS AND RELEVANCE

Annual rates of US CPR training are low and vary widely across communities. Counties located in the South, those with higher proportions of rural areas and of black and Hispanic residents, and those with lower median household incomes have lower rates of CPR training than their counterparts. These data contribute to known geographic disparities in survival of cardiac arrest and offer opportunities for future community interventions.

A neighborhood wealth metric for use in health studies

BACKGROUND

Measures of neighborhood deprivation used in health research are typically based on conventional area-based SES.

PURPOSE

The aim of this study is to examine new data and measures of SES for use in health research. Specifically, assessed property values are introduced as a new individual-level metric of wealth and tested for their ability to substitute for conventional area-based SES as measures of neighborhood deprivation.

METHODS

The analysis was conducted in 2010 using data from 1922 participants in the 2008-2009 survey of the Seattle Obesity Study (SOS). It compared the relative strength of the association between the individual-level neighborhood wealth metric (assessed property values) and area-level SES measures (including education, income, and percentage above poverty as single variables, and as the composite Singh index) on the binary outcome fair/poor general health status. Analyses were adjusted for gender, categoric age, race, employment status, home ownership, and household income.

RESULTS

The neighborhood wealth measure was more predictive of fair/poor health status than area-level SES measures, calculated either as single variables or as indices (lower DIC measures for all models). The odds of having a fair/poor health status decreased by 0.85 (95% CI=0.77, 0.93) per $50,000 increase in neighborhood property values after adjusting for individual-level SES measures.

CONCLUSIONS

The proposed individual-level metric of neighborhood wealth, if replicated in other areas, could replace area-based SES measures, thus simplifying analyses of contextual effects on health.

Association between deprivation status at community level and outcomes from out-of-hospital cardiac arrest: a nationwide observational study

STUDY OBJECTIVES

We sought to examine the association between area deprivation and outcomes of out-of-hospital cardiac arrest in Korea.

METHODS

Data were obtained from the emergency medical service (EMS) system. A nationwide OHCA cohort database from January 2006 to December 2007 was constructed via hospital chart review and ambulance run sheet data. We enrolled all EMS-assessed OHCA victims and excluded cases without available hospital outcome data or residential address. The Carstairs index was used to categorize districts according to level of deprivation into five quintiles, from (Q1, the least deprived) to (Q5, the most deprived). Main outcomes were survival to hospital discharge, survival to admission, and return of spontaneous circulation (ROSC).

RESULTS

34,227 patients were included. Initial rhythm, witnessed status, attempted bystander cardiopulmonary resuscitation (CPR), CPR by EMS, CPR in the emergency department (ED), and elapsed time interval significantly varied according to area deprivation level (p < 0.001). OHCA outcomes were consistently worse in the most deprived areas. The adjusted OR (95% CI) for survival to hospital discharge was 0.58 (0.45-0.77) in the most deprived areas compared to the least deprived areas.

CONCLUSION

Community deprivation was strongly associated with survival among out-of-hospital cardiac arrest patients in Korea.

Socioeconomic status influences bystander CPR and survival rates for out-of-hospital cardiac arrest victims

OBJECTIVES

While lower socioeconomic status is associated with lower level of education and increased incidence of cardiovascular diseases, the impact of socioeconomic status on out-of-hospital cardiac arrest outcomes is unclear. We used residential property values as a proxy for socioeconomic status to determine if there was an association with: (1) bystander CPR rates and (2) survival to hospital discharge for out-of-hospital cardiac arrest.

METHODS

We performed a secondary data analysis of cardiac arrest cases prospectively collected as part of the Ontario Prehospital Advanced Life Support study, conducted in 20 cities with ALS and BLS-D paramedics. We measured patient and system characteristics for cardiac arrests of cardiac origin, not witnessed by EMS, occurring in a single residential dwelling. We obtained property values from the Municipal Property Assessment Corporation. Analyses included descriptive statistics with 95% CIs and stepwise logistic regression.

RESULTS

Three thousand six hundred cardiac arrest cases met our inclusion criteria between 1 January 1995 and 31 December 1999. Patient characteristics were: mean age 69.2, male 67.8%, witnessed 44.7%, bystander CPR 13.2%, VF/VT 33.8%, time to vehicle stop 5:36min:s, return of spontaneous circulation 12.7%, and survival 2.7%. Median property value was $184,000 (range $25,500-2,494,000). For each $100,000 increment in property value, the likelihood of receiving bystander CPR increased (OR=1.07; 95% CI 1.01-1.14; p=0.03) and survival decreased (OR=0.77; 95% CI 0.61-0.97; p=0.03).

CONCLUSIONS

This is the largest study showing an association between socioeconomic status and survival, and the first study showing an association with bystander CPR. Our findings suggest targeting CPR training among lower socioeconomic groups.

Cerebral resuscitation: state of the art, experimental approaches and clinical perspectives

Neuronal injury following global cerebral ischemia continues to bea central problem of patients in the postresuscitation phase following cardiocirculatory arrest. In addition to measures focusing on rapid restoration of spontaneous circulation, the most effective treatment after cardiac arrest, as shown by large randomized trials,is the use of therapeutic mild hypothermia. Current guidelines of the International Liaison Committee on Resuscitation (ILCOR)are recommending the use of therapeutic mild hypothermia for all unconscious patients after cardiac arrest. At present there is no specific neuroprotective treatment available. Promising animal experimental data concerning the use of thrombolytic agents during cardiopulmonary resuscitation have led to a large European multicenter trial (TROICA trial) that will provide its data in 2006.

Cardiopulmonary Resuscitation Programs Revisited: Results of a Community Study Among Older African Americans

Early cardiopulmonary resuscitation (CPR) performed by a layperson and prompt defibrillation in the field are critical links in the chain of survival of out-of-hospital sudden cardiac arrest. It has been suggested that minorities, women, and elderly persons are often left out of CPR training programs. To examine knowledge and attitudes toward CPR and automatic external defibrillation among African Americans, the author and colleagues conducted home interviews in a population sample of 425 older men and women in Miami-Dade County, FL. It was found that 25% of the participants did not know what CPR was. Only 18% of men and 28% of women had ever taken CPR classes. Mean age the time of CPR training was for men 36 years and for women 46 years. About 74% of all subjects did not know whom to contact for CPR training, and fewer than 5% knew about the American Heart Association Heartsaver Program (including automatic external defibrillation performed by laypersons). The majority of participants suggested churches or community organizations as organizers of CPR training. This study shows that there is a major need for improving knowledge and intensifying CPR training programs among older African Americans. Community organizations and churches may play a critical role in reaching this goal.

Time trends in long-term mortality after out-of-hospital cardiac arrest, 1980 to 1998, and predictors for death

BACKGROUND

We studied time trends in long-term survival after out-of-hospital cardiac arrest (OHCA) for patient characteristics and described predictors for death after discharge. Because long-term prognosis among patients with coronary heart disease has improved in the last decades, we hypothesized that the prognosis after OHCA would improve with time.

METHODS

We analyzed data that were prospectively collected from all patients discharged from the hospital after OHCA in the community of Göteborg, Sweden, from 1980 to 1998 and divided the data into 2 time periods, 1980 to 1991 and 1991 to1998, with an equal number of patients.

RESULTS

A total of 430 patients were included in the survey. Age, sex proportions, cardiovascular comorbidity, resuscitation factors, and inhospital complications did not change with time. A diagnosis of a precipitating myocardial infarction was more common during period 1 (66% vs 54%). The prescription of aspirin (22% vs 52%), angiotensin-converting enzyme inhibitors (7% vs 29%), anticoagulants (13% vs 27%), and lipid-lowering agents (0% vs 6%) at discharge increased during period 2. Long-term survival did not improve with time; the 5-year mortality rates were 53% in period 1 and 52% in period 2. Independent predictors of an increased risk of death included age (risk ratio [RR] 1.06, 95% CI 1.05-1.08), history of myocardial infarction (RR 2.02, 95% CI 1.51-2.72), history of smoking (RR 1.77, 95% CI 1.29-2.44), and worse cerebral performance at discharge (RR 1.71, 95% CI 1.44-2.02). The prescription of beta-blockers at discharge was independently predictive of decreased risk of death (RR 0.63, 95% CI 0.46-0.85).

CONCLUSION

The long-term survival rate after OHCA did not change. Baseline characteristics remained generally unchanged, but the drugs prescribed at discharge changed in several aspects. Age, a history of myocardial infarction, a history of smoking, cerebral performance category at discharge, and the prescription of beta-blockers were independent predictors of outcome.

Dispatcher assisted CPR: implementation and potential benefit. A 12-year study

OBJECTIVES

Our objectives are to describe details of the dispatcher assisted cardiopulmonary resuscitation (CPR) instruction program we implemented during a 12 years study and to provide estimates of the potential number of out-of-hospital cardiac arrests that might benefit from such instruction based on data from the last 77 months.

METHODS

Basic data were obtained for all episodes of out-of-hospital cardiac arrest in the city of Seattle, as well as all emergency medical services (EMS) dispatches for suspected cardiac arrest. In addition to EMS run reports, data sources included audio tapes of dispatches, and interviews of callers. These data were used in a potential benefit analysis.

RESULTS

Over a period of 77 months, 54% (3320/6130) of cardiac arrests received advanced cardiac life support (ACLS) by Seattle Fire Department emergency medical technicians (EMTs) and paramedics. We estimated that 29.9% (994/3320) of cardiac arrests in Seattle treated by EMS could have theoretically benefited from dispatcher assisted CPR. No serious adverse consequences of a dispatcher assisted CPR program were observed. Failure to identify a cardiac arrest by dispatchers was largely attributed to deviation from a well-defined protocol. However, non-arrests identified, initially as arrests appeared to be unavoidable.

CONCLUSIONS

In the city of Seattle, some 29.9% of all out-of-hospital cardiac arrest victims who received ACLS had the potential to benefit from dispatcher assisted CPR.

Characteristics and outcome among patients having out of hospital cardiac arrest at home compared with elsewhere

OBJECTIVE

To describe the characteristics and outcome of patients who have a cardiac arrest at home compared with elsewhere out of hospital.

PATIENTS

Subjects were patients included in the Swedish cardiac arrest registry between 1990 and 1999. The registry covers about 60% of all ambulance organisations in Sweden.

METHODS

The study sample comprised patients reached by the ambulance crew and in whom resuscitation was attempted out of hospital. There was no age limit. Crew witnessed cases were excluded. The patients were divided into two groups: cardiac arrest at home and cardiac arrest elsewhere.

RESULTS

Among a study population of 24 630 patients the event took place at home in 16 150 (65.5%). Those in whom the arrest took place at home differed from the remainder in that they were older, were more often women, less often had a witnessed cardiac arrest, were less often exposed to bystander cardiopulmonary resuscitation (CPR), were less often found in ventricular fibrillation, and had a longer interval between collapse and call for ambulance, arrival of ambulance, start of CPR, and first defibrillation. Of patients in whom the arrest took place at home, 11.3% were admitted to hospital alive, v 19.4% in the elsewhere group (p < 0.0001); corresponding figures for survival after one month were 1.7% v 6.2% (p < 0.0001). The adjusted odds ratio for survival after one month (at home v not at home; considering age, sex, initial arrhythmia, bystander CPR, aetiology, and whether the arrest was witnessed) was 0.40 (95% confidence interval 0.33 to 0.49; p < 0.0001).

CONCLUSIONS

Sixty five per cent of out of hospital cardiac arrests in Sweden occur at home. The patients differed greatly from those with out of hospital cardiac arrests elsewhere, and fewer than 2% were alive after one month. Having an arrest at home was a strong independent predictor of adverse outcome. Further research is needed to identify the reasons for this.

Out-of-hospital cardiac arrest in men and women

BACKGROUND

The incidence of sudden cardiac death is roughly 3 times greater in men than in women. However, in patients treated for out-of-hospital cardiac arrest, the relationships between sex and survival after adjustment for age and cardiac rhythm are unclear.

METHODS AND RESULTS

In this retrospective cohort study, we examined 7069 men and 2582 women who were treated for out-of-hospital cardiac arrest in Seattle and suburban King County between 1990 and 1998. We compared successful prehospital resuscitation (hospital admission) and survival from event to discharge in men and women. Women had markedly reduced rates of ventricular fibrillation (VF), slightly older age, fewer witnessed arrests, and fewer arrests in public locations than men. Although their unadjusted resuscitation rate was lower (29% versus 32%, P<0.0001), women had a greater likelihood of resuscitation than men after adjustment for VF (odds ratio [OR] 1.13; 95% confidence interval [CI], 1.03 to 1.25) and after adjustment for VF plus additional factors (OR, 1.27; 95% CI, 1.14 to 1.41). The difference in resuscitation rates between men and women decreased as they aged (test for trend, P<0.0001). Unadjusted survival rates were also lower in women than in men (11% versus 15%, P<0.0001). Women had similar survival after adjustment for VF (OR, 0.97; 95% CI, 0.85 to 1.11) and after adjustment for VF plus additional factors (OR, 1.09; 95% CI, 0.93 to 1.27).

CONCLUSIONS

The lower unadjusted resuscitation and survival rates observed in women were primarily due to women's lower incidence of VF, a relatively favorable cardiac rhythm. After adjustment for VF and other factors, women had higher resuscitation rates than men, but similar rates of survival from event to discharge.

Geographical distribution of cardiac arrest in Nottinghamshire

BACKGROUND

to analyse the incidence of out-of-hospital cardiac arrest in Nottinghamshire; to ascertain its geographical distribution; and to determine whether the geography of coronary heart disease mortality and out-of-hospital cardiac arrest are the same.

METHODS AND RESULTS

population based, retrospective study in the County of Nottinghamshire with a total population of 993,914 in an area of 2183 km2 divided into 191 electoral areas. In the 4 years from 1 January, 1991 to 31 December, 1994, 1634 patients sustained a cardiac arrest attributed to a cardiac cause (International Classification of Diseases codes 390-414 and 420-429) and were attended by the Nottinghamshire Ambulance Service. The overall crude mean incidence rate of community cardiac arrest per electoral area was 40.2 per 100,000 population (range 0-121.2). Thirteen electoral areas, relatively deprived according to the Townsend score, had a significantly greater than expected incidence rate of cardiac arrest (median of 75.6/100,000 per electoral area; interquartile range (IQR) 65.3, 83.8). Twelve relatively affluent electoral areas had a significantly lower than expected incidence rate (median of 18.5/100,000 per area (IQR 13.0, 28.7). After adjusting for deprivation index, there were no differences in coronary heart disease (CHD) mortality and community cardiac arrest in urban and rural electoral areas. Apart from response times by ambulance crews, the events that follow the cardiac arrest such as bystander resuscitation, ventricular fibrillation found as the presenting rhythm and survival were similar in all electoral areas.

CONCLUSIONS

increasing level of deprivation is associated with areas of increased incidence of out-of-hospital cardiac arrest in Nottinghamshire, and the effect is apparently different from that on CHD mortality. There is scope for reducing incidence rates of community cardiac arrest and to introduce strategies to improve survival in areas identified as having high rates of community cardiac arrest.

Is hospital care of major importance for outcome after out-of-hospital cardiac arrest? Experience acquired from patients with out-of-hospital cardiac arrest resuscitated by the same Emergency Medical Service and admitted to one of two hospitals over a 16-year period in the municipality of Göteborg

AIM

To describe patient characteristics, hospital investigations and interventions and early mortality among patients being hospitalized after out-of-hospital cardiac arrest in two hospitals.

SETTING

Municipality of Göteborg, Sweden.

PATIENTS

All patients suffering an out-of-hospital cardiac arrest who were successfully resuscitated and admitted to hospital between 1 October 1980 and 31 December 1996. All patients were resuscitated by the same Emergency Medical Service and admitted alive to one of the two city hospitals in Göteborg.

RESULTS

Of 579 patients admitted to Sahlgrenska Hospital, 253 (44%) were discharged alive and of 459 patients admitted to Ostra Hospital, 152 (33%) were discharged alive (P < 0.001). More patients in Sahlgrenska Hospital were still receiving cardiopulmonary resuscitation (CPR) treatment (P = 0.03), but patients in Ostra had a lower systolic blood pressure and higher heart rate on admission. A larger percentage of patients admitted to Sahlgrenska Hospital underwent coronary angiography (P < 0.001), electrophysiological testing (P < 0.001), Holter recording (P < 0.001), echocardiography (P = 0.004), percutaneous transluminal coronary angioplasty (PTCA, P = 0.009), implantation of automatic implantable cardioverter defibrillator (AICD, P = 0.03) and exercise stress tests (P = 0.003). Inhabitants in the catchment area of Ostra Hospital had a less favourable socio-economic profile.

CONCLUSION

Survival after out-of-hospital cardiac arrest may be affected by the course of hospital management. Other variables that might influence survival are socio-economic factors and cardiorespiratory status on admission to hospital. Further investigation is called for as more patients are being hospitalised alive after out-of-hospital cardiac arrest.

Long term outcome after out-of-hospital cardiac arrest with physician staffed emergency medical services: the Utstein style applied to a midsized urban/suburban area

OBJECTIVE

To test the effect of a physician staffed advanced cardiac life support (ALS) system on patient outcome following out-of-hospital cardiac arrest.

DESIGN

Observational study.

SETTING

Two tier basic life support (BLS) and physician staffed ALS services in the midsized urban/suburban area of Heidelberg, Germany.

PATIENTS

All patients suffering out-of-hospital cardiac arrest of cardiac aetiology between January 1992 and December 1994 and who were covered by ALS services.

INTERVENTIONS

Physician staffed ALS services.

MAIN OUTCOME MEASURES

Return of spontaneous circulation, hospital discharge, and one year survival, according to the Utstein style.

RESULTS

Of 330 000 inhabitants, 755 suffered from cardiac arrest covered by the Heidelberg ALS services. In 512 patients, cardiopulmonary resuscitation had been initiated. Of 338 patients with cardiac aetiology, return of spontaneous circulation was achieved in 164 patients (49%), 48 (14%) were discharged alive, and 40 (12%) were alive one year later; most of these patients showed good neurological outcome. Thus, 4.85 patients with cardiac aetiology were saved by the ALS services and discharged alive per 100 000 inhabitants a year. Ventricular fibrillation or tachycardia was detected in 106 patients (31%), other cardiac rhythms in 40 (12%), and asystole in 192 (57%). Hospital discharge rates (and one year survival) in these subgroups were 34.0% (29.2%), 12.5% (7.5%), and 3.6% (3.1%), respectively. Discharge rates increased if cardiac arrest was witnessed (bystander, 20.0%; BLS/ALS personnel, 21.4%; non-witnessed arrest, 3.3%; p < 0.01), and if the time period between the alarm and the arrival of the ALS unit was four minutes or less (</= 4 minutes, 30.6%; 4-8 minutes, 10.4%; > 8 minutes, 8. 1%; p < 0.001). In 69 patients with bystander witnessed cardiac arrest with ventricular fibrillation, the discharge rate was 37.7%; 21 patients were alive after one year.

CONCLUSIONS

A two tier BLS and physician staffed ALS system is associated with good long term outcome of patients suffering from out-of-hospital cardiac arrest of cardiac aetiology in a midsized urban/suburban area. Further studies, however, are required to assess whether having a physician in the ALS unit is an independent determinant for improved long term outcome.

Neighborhoods matter: a population-based study of provision of cardiopulmonary resuscitation

STUDY OBJECTIVE

Cardiorespiratory resuscitation (CPR) nonprovision-the failure of bystanders to provide CPR to cardiac arrest victims-remains a well-documented public health problem associated with significant mortality. Multivariate data on failure to provide CPR are limited. Given the established independent contributions of neighborhoods to explaining many behaviors, we asked the following questions: Do neighborhood characteristics affect the likelihood of CPR nonprovision? In particular, we sought to identify the characteristics of areas that have had the most success in providing CPR.

METHODS

We performed multivariable logistic regression analysis of a prospectively collected cohort of 4,379 cardiac arrests linked at an individual level to neighborhood data from the US Census. These arrests represent all out-of-hospital cardiac arrests in the City of Chicago in 1987 and 1988.

RESULTS

In multivariate analysis, patients who had cardiac arrests who lived in neighborhoods where cardiac arrests were more common were significantly more likely to receive CPR. Patients with arrests in racially integrated neighborhoods were most likely to be provided with CPR, followed by those in predominately white neighborhoods, with the lowest rates of CPR provision in predominately black neighborhoods. Neither the socioeconomic status, number of elderly, nor the occupational characteristics of the neighborhood appeared to influence CPR provision. At the individual level, in-home arrests and arrests among middle-aged black residents (relative to older black and all white residents) were less likely to receive CPR.

CONCLUSION

Substantial variation in rates of CPR nonprovision exists between neighborhoods; the variation is associated with neighborhood characteristics. Combining individual and neighborhood data allows identification of important factors associated with the failure to provide CPR.

Does race or socioeconomic status predict adverse outcome after out of hospital cardiac arrest: a multi-center study

OBJECTIVE

To assess whether socioeconomic status (SES) or race is associated with adverse outcome after an out-of-hospital cardiac arrest (OHCA).

METHODS

A convenience sample of OHCA of presumed cardiac origin from seven suburban cities in Michigan, 1991-1996. Median household income (HHI), utilizing patient home address and 1990 census tract data, was dichotomized above and below 1990 state median income. Patient race was dichotomized as black or white. Outcome was defined as survival to hospital discharge (DC). Multiple logistic regression and Pearson's chi2 values were used for analysis.

RESULTS

Of 1317 cases with complete data for analysis, the average age was 67.3 +/- 16.0, 939 (71.1%) were white, 587 (44.4%) arrests were witnessed (WIT), and 65 (4.9%) were DC alive. There was no significant difference between races with respect to WIT arrests, V(T)/V(F) arrest rhythms, and a small difference in EMS response interval. Whites were more likely to be above median HHI (57.1 vs. 26.2%, P < 0.001). Adjusted odds ratios for predictors of survival were WIT arrest (OR = 3.76, 95% CI (1.7, 8.2)), V(T)/V(F) (OR = 8.74, 95% CI (3.7, 10.8), but not race (OR = 0.68, 95% CI (0.3, 1.4)) or SES (OR = 1.51, 95% C1 0.8, 2.8).

CONCLUSION

In this population, neither race nor SES was independently associated with a worse outcome after OHCA.

Race and survival after out-of-hospital cardiac arrest in a suburban community

STUDY OBJECTIVE

To determine whether race, when controlled for income, is an independent predictor of survival to hospital discharge after out-of-hospital cardiac arrest (OHCA).

METHODS

Prospective OHCA data were collected over 4 years (1991-1994) from a convenience sample of OHCA patients transported to nine hospitals in three suburban counties. Race was determined from hospital and vital statistics records. The average household income was identified from ZIP codes and used as a marker of socioeconomic status. Demographic data and known predictors of survival were compared between blacks and whites. A logistic regression analysis was used to assess the association between race, income, and survival.

RESULTS

Of the 1,690 patients, 223 (13%) were blacks and 1,467 (87%) were whites. Average household income was less for blacks than for whites ($40,225 versus $46,193; P < .001), but both populations were affluent by national standards (national percentile ranks were 73% and 88%, respectively). The populations were no different in percentage of witnessed arrests (57% versus 61%; P = .465). Blacks were younger (mean +/- SD, 62 +/- 16 versus 68 +/- 15 years; P < .001); less frequently received bystander CPR (11% versus 20%; P = .002); less often had ventricular tachycardia or ventricular fibrillation (37% versus 50%; P < .001); and had a shorter advanced life support call-response interval (median, 4 versus 6 minutes; P < .001). The odds ratio for survival (white/black) was .931 (95% confidence interval, .446 to 1.945).

CONCLUSION

Race was not found to predict adverse OHCA outcomes in this affluent population.

Sudden cardiac death in Hispanic Americans and African Americans

OBJECTIVES

The goal of this study was to estimate rates of sudden cardiac death in US Hispanics and African Americans.

METHODS

Data on coronary deaths occurring outside of the hospital or in emergency rooms were examined for 1992.

RESULTS

In 1992, 53% (8194) of coronary heart disease deaths among Hispanic Americans 25 years of age and older occurred outside of the hospital or in emergency rooms. The percentage was lower among Hispanics than among non-Hispanic Whites and Blacks. Age-adjusted rates per 100,000 were lower in Hispanics than in non-Hispanic Whites or Blacks (Hispanic men, 75; White men, 166; Black men, 209; Hispanic women, 35; White women, 74; Black women, 108). The percentages dying outside of the hospital or in emergency rooms were higher in young persons, those living in nonurban areas, and those who were single.

CONCLUSIONS

The percentage and rate of coronary deaths occurring outside of the hospital or in emergency rooms were lower in Hispanics than in non-Hispanics; African Americans had the highest rates. Further research is needed on sudden coronary death in Hispanic Americans and African Americans.

Cardiac arrest witnessed by prehospital personnel: intersystem variation in initial rhythm as a basis for a proposed extension of the Utstein recommendations

STUDY OBJECTIVE

To test the hypothesis that intersystem variation in initial rhythm among EMS-witnessed arrests is of sufficient magnitude to warrant standardization of survival by creation of an Utstein-style denominator of EMS-witnessed ventricular fibrillation (VF).

METHODS

We conducted a planned subset analysis of a prospective observational cohort study of consecutive EMS-witnessed adult cardiac arrests occurring in New York City and meeting Utstein entry criteria. The primary outcome measure was intersystem variation in frequency of EMS-witnessed VF in New York City compared with that in other EMS systems. Secondary outcome measures were variations in survival after EMS-witnessed VF arrests and overall survival after all EMS-witnessed arrests.

RESULTS

Intersystem variation showed a threefold difference in the frequency of EMS-witnessed VF (24% in New York City versus 77% in Scotland; 99% confidence interval [CI] for 53% difference, 43% to 63%; P < 10(-7), a twofold difference in survival after EMS-witnessed VF (25% in NYC versus 48% in King County, WA; 99% CI for 23% difference, 6% to 39%; P < .002), and a fourfold difference in survival after all EMS-witnessed arrests (9% in New York City versus 35% in King County; 99% CI for 26% difference, 18% to 34%; P < 10(-7).

CONCLUSION

The marked variation in frequency of initial rhythm in EMS-witnessed arrests suggests that a modified Utstein denominator of EMS-witnessed VF would facilitate more uniform intersystem comparison of survival in this unique cohort. However, even after adjustment for initial rhythm, large residual intersystem survival differences remain unexplained.

Predicting survival from out-of-hospital cardiac arrest: a multivariate analysis

From 954 attempts to resuscitate patients from out-of-hospital cardiac arrest two datasets were derived, namely 861 cases of cardiac arrest and 906 cases of either cardiac or primary respiratory arrest. For each dataset, multivariate analysis was performed by fitting a number of explanatory variables with respect to the outcomes of admission to hospital and discharge home in logistic regression models. There were numerous interactions between these variables. Being conscious at the time of the arrival of the ambulance crew and subsequently having cardiac arrest strongly predicted survival, as did both the presence of a witness to the arrest and the initiation of cardiopulmonary resuscitation (CPR) by a bystander; this latter effect was a marker for early CPR. The strongest predictor of a poor outcome was delay to CPR or delay to advanced cardiac life support.

Out-of-hospital cardiac arrests: an 8-year New York City experience

A retrospective study was conducted to determine the outcome of out-of-hospital cardiac arrests by one prehospital system in New York City from January, 1986, through December, 1993. The results were recorded consistent with the Utstein Style. Of 481 attempted patient resuscitations 406 were of cardiac etiology, with 382 patients having arrested prior to EMS arrival; their overall survival rate was 2.1% (8/382). Cardiac arrests were witnessed in 246 patients. Of the witnessed arrest patients found in ventricular fibrillation (96/246), the overall survival rate was 7.3% (7/96). Of the 7 survivors who were discharged from the hospital, 71.4% (5/7) had a good cerebral performance/good overall performance. Of 24 patients who arrested in the presence of EMS, the survival rate was 12.5% (3/24). This study confirms a poor survival rate for patients suffering out-of-hospital cardiac arrests in New York City.

Influence of comorbidity on the outcome of patients treated for out-of-hospital ventricular fibrillation

BACKGROUND

A number of factors have previously been shown to be predictive of survival from out-of-hospital ventricular fibrillation. These include witnessed collapse, prompt initiation of cardiopulmonary resuscitation, early application of defibrillation, and younger age. Arrests occurring away from home are also associated with improved survival. Additionally, hospital mortality after successful resuscitation has been related to a history of congestive heart failure as well as to some of the factors noted above. An association of prearrest comorbidity with outcome has not been systematically evaluated.

METHODS AND RESULTS

We define here a comorbidity index, which is constructed from histories of chronic conditions as well as a number of recent symptoms in 282 victims of out-of-hospital VF. This indicator of comorbidity is strongly associated with outcome (P = .004). However, when analyzing a comprehensive set of predictors of survival after out-of-hospital ventricular fibrillation, including the index of comorbidity, we could identify overall only about one fourth of the variation that one might hope to account for.

CONCLUSIONS

Comorbidity appears to be an important (but usually overlooked) predictor of survival from out-of-hospital ventricular fibrillation. However, most of the statistical variability in predicting survival remains unexplained when we consider comorbidity in conjunction with previously identified predictors of survival.

Success of cardiopulmonary resuscitation after heart attack in hospital and outside hospital

OBJECTIVES

To determine factors associated with cardiopulmonary resuscitation being attempted after cardiac arrest from myocardial infarction, in or outside hospital, and estimate short term and long term survival rates.

DESIGN

Descriptive cross sectional and cohort study.

SETTING

Community based register of all suspected heart attacks and sudden cardiac deaths in Lower Hunter region of New South Wales, Australia.

SUBJECTS

4924 men and women aged 25-69.

MAIN OUTCOME MEASURES

Rates of attempted cardiopulmonary resuscitation and survival after successful resuscitation.

RESULTS

Cardiopulmonary resuscitation was attempted in 41% of cases of cardiac arrest after myocardial infarction outside hospital and 63% of cases in hospital. Survival rates at 28 days were 12% and 39% respectively. Among the survivors, although 41% had another myocardial infarction (or coronary death), 81% of both groups were still alive two years later. Younger and better educated people were more likely to receive cardiopulmonary resuscitation in either setting, and being married predicted cardiopulmonary resuscitation being attempted outside hospital. Younger age predicted better survival rates after attempted resuscitation in hospital.

CONCLUSIONS

The reasons for better education to predict cardiopulmonary resuscitation being attempted need explanation. The higher survival rate after cardiopulmonary resuscitation in hospital compared with outside hospital and the good long term prognosis for survivors in both settings suggest that attempts to improve success of cardiopulmonary resuscitation outside hospital may be worth while.

Outcomes in African-American women with suspected acute myocardial infarction: the Myocardial Infarction Triage and Intervention Project

Increasing attention has been given to the investigation of cardiovascular disease in women, although African-American women have received little attention. This study compares characteristics and outcomes in women admitted to coronary care units for suspected acute myocardial infarction (MI). Between January 1988 and December 1991, a total of 554 (5%) African-American and 9738 (95%) white women with suspected acute MI were admitted to coronary care units in metropolitan Seattle, Washington. Relevant demographic socioeconomic, clinical, and outcome data were abstracted from the medical record and entered in the Myocardial Infarction Triage and Intervention registry. African-American women were younger, more often single and unemployed, and were less likely to have health insurance than their white counterparts. In addition, a higher proportion of African-American women reported a history of hypertension and diabetes mellitus. After adjustment for age, African-American women were equally as likely to develop acute MI and were more likely to die in the hospital. In addition, a higher proportion of African-American women were readmitted to coronary care units for suspected MI. Compared with their white counterparts, African-American women with suspected acute MI were considerably worse off from both socioeconomic and clinical standpoints, and their relative disadvantage was apparent in poor outcomes.

Racial differences in the incidence of cardiac arrest and subsequent survival. The CPR Chicago Project

BACKGROUND

Differences between blacks and whites have been reported in the incidence of several forms of cardiovascular disease, including hypertension and stroke. We examined racial differences in the incidence of cardiac arrest in a large urban population and in subsequent survival.

METHODS

We collected data on all nontraumatic, out-of-hospital cardiac arrests in Chicago from January 1, 1987, through December 31, 1988, and compared the incidence and survival rates for blacks and whites. We examined the association between survival and race and seven other known risk factors by logistic-regression analysis. We computed incidence rates by coupling our data with U.S. Census population data.

RESULTS

Our study population comprised 6451 patients: 3207 whites, 2910 blacks, and 334 persons of other races. The incidence of cardiac arrest was significantly higher for blacks than for whites in every age group. The survival rate after cardiac arrest was 2.6 percent in whites, as compared with 0.8 percent in blacks (P < 0.001). Blacks were significantly less likely to have a witnessed cardiac arrest, bystander-initiated cardiopulmonary resuscitation, or a "favorable" initial rhythm or to be admitted to the hospital. When they were admitted, blacks were half as likely to survive. The association between race and survival persisted even when other recognized risk factors were taken into account. We did not find important differences between blacks and whites in the response times of the emergency medical services.

CONCLUSIONS

The black community in our study was at higher risk for cardiac arrest and subsequent death than the white community, even after we controlled for other variables.