Geographical distribution of cardiac arrest in Nottinghamshire

Association of socioeconomic status with 30-day survival following out-of-hospital cardiac arrest in Scotland, 2011-2020

BACKGROUND AND AIMS

The aim of this study was to investigate the crude and adjusted association of socioeconomic status with 30-day survival after out-of-hospital cardiac arrest (OHCA) in Scotland and to assess whether the effect of this association differs by sex or age.

METHODS

This is a population-based, retrospective cohort study, including non-traumatic, non-Emergency Medical Services witnessed patients with OHCA where resuscitation was attempted by the Scottish Ambulance Service, between 1 April 2011 and 1 March 2020. Socioeconomic status was defined using the Scottish Index of Multiple Deprivation (SIMD). The primary outcome was 30-day survival after OHCA. Crude and adjusted associations of SIMD quintile with 30-day survival after OHCA were estimated using logistic regression. Effect modification by age and sex was assessed by stratification.

RESULTS

Crude analysis showed lower odds of 30-day survival in the most deprived quintile relative to least deprived [odds ratio (OR) 0.74, 95% confidence interval (CI) 0.63-0.88]. Adjustment for age, sex, and urban/rural residency decreased the relative odds of survival further (OR 0.56, 95% CI 0.47-0.67). The strongest association was observed in males <45 years old. Across quintiles of increasing deprivation, evidence of decreasing trends in the proportion of those presenting with shockable initial cardiac rhythm, those receiving bystander cardiopulmonary resuscitation, and 30-day survival after OHCA were found.

CONCLUSIONS

Socioeconomic status is associated with 30-day survival after OHCA in Scotland, favouring people living in the least deprived areas. This was not explained by confounding due to age, sex, or urban/rural residency. The strongest association was observed in males <45 years old.

The incidence and outcomes of out-of-hospital cardiac arrest in metropolitan versus rural locations: A systematic review and meta-analysis

BACKGROUND/AIMS

Rurality poses a unique challenge to the management of out-of-hospital cardiac arrest (OHCA) when compared to metropolitan (metro) locations. We conducted a systematic review of published literature to understand how OHCA incidence, management and survival outcomes vary between metro and rural areas.

METHODS

We included studies comparing the incidence or survival of ambulance attended OHCA in metropolitan and rural areas, from a search of five databases from inception until 9th March 2022. The primary outcomes of interest were cumulative incidence and survival (return of spontaneous circulation, survival to hospital discharge (or survival to 30 days)). Meta-analyses of OHCA survival were undertaken.

RESULTS

We identified 28 studies (30 papers- total of 823,253 patients) across 13 countries of origin. The definition of rurality varied markedly. There was no clear difference in OHCA incidence between metro and rural locations. Whilst there was considerable statistical heterogeneity between studies, the likelihood of return of spontaneous circulation on arrival at hospital was lower in rural than metro locations (OR = 0.53, 95% CI 0.40, 0.70; I² = 89%; 5 studies; 90,934 participants), as was survival to hospital discharge/survival to 30 days (OR = 0.52, 95% CI 0.38, 0.71; I² = 95%; 15 studies; 18,837 participants).

CONCLUSIONS

Overall, while incidence did not vary, the odds of OHCA survival to hospital discharge were approximately 50% lower in rural areas compared to metro areas. This suggests an opportunity for improvement in the prehospital management of OHCA within rural locations. This review also highlighted major challenges in standardising the definition of rurality in the context of cardiac arrest research.

A Comparative Study Between Amiodarone and Implantable Cardioverter-Defibrillator in Decreasing Mortality From Sudden Cardiac Death in High-Risk Patients: A Systematic Review and Meta-Analysis

Sudden cardiac death (SCD) is an unexpected death that occurs within one hour of symptom onset. In the United States, sudden cardiac death is considered the leading cause of natural death, accounting for 325,000 adult patients annually. SCD is more common in adult patients (above the mid-30s) and men. The risk factors that predict SCD are categorized into clinical, sociological, genetic, and psychological. To prevent the occurrence of SCD, several treatment options, especially antiarrhythmic drugs and implantable cardioverter-defibrillator (ICD), have been used.

A literature search from 2000 to 2022 was conducted on six electronic databases: PubMed, Cochrane Library, Web of Science, Embase, ScienceDirect, and Google Scholar. The search query used Boolean expressions and keywords such as amiodarone, implantable cardioverter-defibrillator, sudden cardiac death, cardiac arrest, arrhythmic death, and all-cause mortality. The articles identified from the literature search were screened using the eligibility criteria, resulting in eight articles relevant for inclusion in the review. A meta-analysis of data from six of the included studies showed that ICD was more effective in the reduction of SCD rates, with an SCD rate of 5.97% (n = 84/1,408) observed in the ICD group compared with an SCD rate of 11.81% (n = 168/1,423) observed in the amiodarone group. The results also show that ICD was more effective in reducing all-cause mortality compared with amiodarone (odds ratio (OR): 1.36; 95% confidence interval (CI): 1.06-1.74; I² = 57%; P = 0.03).

ICD treatment of high-risk patients was more effective in reducing SCD and all-cause mortality rates compared with amiodarone treatment. There is evidence that amiodarone can be used as an adjuvant treatment option, especially for patients who are not eligible for ICD treatment and those who face more adverse events. Evidence has also shown that using amiodarone with ICD treatment significantly improves survival rates compared to ICD treatment only.

Awareness and attitude of final year students towards the learning and practice of cardiopulmonary resuscitation at the University of Ibadan in Nigeria

Introduction

Out-of-hospital cardiac arrest (OHCA) is a major cause of sudden cardiac death which can be prevented by early cardiopulmonary resuscitation (CPR). International bodies recommend that basic life support (BLS) skills be taught in schools in order to increase the rate of bystander CPR and reduce mortality from OHCA. We are not aware of any BLS education program for non-healthcare students in Nigeria. This study was to assess the awareness and attitude to acquiring BLS skills among university students.

Methods

We conducted a cross-sectional study among final year university undergraduates using a questionnaire that assessed students' sociodemographic characteristics, awareness of CPR, previous experiences, and attitude to basic life support (BLS). Counts and proportions were compared for the demographic characteristics using Chi-squared and Fisher's exact tests.

Results

Four hundred and seventy-five students from 15 faculties participated in this study, median age was 22.8 years (interquartile range: 21.2–24.5 years). Majority (82.5%) have heard of CPR, 29.7% have undergone CPR training; 77.3% of those who had been trained were confident that they could perform CPR. Previous CPR training was significantly associated with faculty, year of study and age. Eighty-nine (18.7%) students have witnessed someone die from a trauma. Four hundred and fifty (94.7%) respondents would like to get BLS training, 440 (92.6%) think that CPR training should be included in the school curriculum.

Conclusion

There is good awareness and positive attitude to the acquisition and practice of cardiopulmonary resuscitation among university students in Nigeria. Few students however, have been trained to administer bystander cardiopulmonary resuscitation. Therefore, there is a need to implement university wide BLS education in Nigeria.

Factors associated with knowledge and attitude towards adult cardiopulmonary resuscitation among healthcare professionals at the University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia: an institutional-based cross-sectional study

OBJECTIVE

This study was conducted to assess the factors associated with knowledge and attitude towards adult cardiopulmonary resuscitation (CPR) among health professionals at the University of Gondar Hospital, Northwest Ethiopia.

STUDY DESIGN

An institutional-based cross-sectional study was conducted from 15 February to 15 March 2018. Both bivariable and multivariable logistic regression analyses were used to identify factors associated with knowledge and attitude level of health professionals towards CPR. Variables with a p value less than <0.2 in the bivariable analysis were fitted into the multivariable analysis. In the multivariable analysis, variables with a p value <0.05 were considered statistically significant.

SETTING

University of Gondar Comprehensive Specialized Hospital, Northwest Ethiopia.

PARTICIPANTS

A total of 406 health professionals (physicians, nurses, anaesthetists, health officers and midwives) were included.

RESULTS

Among the study participants, 25.1% (95% CI 21.2 to 29.3) had good knowledge and 60.8% (95% CI 55.9 to 65.5) had good attitude towards adult CPR. Work experience (adjusted OR (AOR): 5.02, 95% CI 1.25 to 20.20), number of work settings (AOR: 6.52, 95% CI 2.76 to 15.41), taking CPR training (AOR: 2.76, 95% CI 1.40 to 5.42), exposure to cardiac arrest case (AOR: 2.16, 95% CI 1.14 to 4.07) and reading CPR guidelines (AOR: 5.57, 95% CI 2.76 to 11.20) were positively associated with good knowledge. Similarly, taking CPR training (AOR: 1.74, 95% CI 1.42 to 1.53) and reading CPR guidelines (AOR: 2.74, 95% CI 1.55 to 4.85) were positively associated with good attitude.

CONCLUSIONS

The level of knowledge and attitude of health professionals towards adult CPR was suboptimal. Health professionals who were taking CPR training and reading CPR guidelines had good knowledge and attitude towards CPR. In addition, work experience, number of work settings and exposure to cardiac arrest case had a positive association with CPR knowledge. Thus, providing regular CPR training and work setting rotations is highly crucial.

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.

Characteristics of neighbourhoods with high incidence of out-of-hospital cardiac arrest and low bystander cardiopulmonary resuscitation rates in England

Aims

The aim of the project was to identify the neighbourhood characteristics of areas in England where out-of-hospital cardiac arrest (OHCA) incidence was high and bystander cardiopulmonary resuscitation (BCPR) was low using registry data.

Methods and results

Analysis was based on 67 219 cardiac arrest events between 1 April 2013 and 31 December 2015. Arrest locations were geocoded to give latitude/longitude. Postcode district was chosen as the proxy for neighbourhood. High-risk neighbourhoods, where OHCA incidence based on residential population was >127.6/100 000, or based on workday population was >130/100 000, and BCPR in bystander witnessed arrest was <60% were observed to have: a greater mean residential population density, a lower workday population density, a lower rural-urban index, a higher proportion of people in routine occupations and lower proportion in managerial occupations, a greater proportion of population from ethnic minorities, a greater proportion of people not born in UK, and greater level of deprivation. High-risk areas were observed in the North-East, Yorkshire, South-East, and Birmingham.

Conclusion

The study identified neighbourhood characteristics of high-risk areas that experience a high incidence of OHCA and low bystander resuscitation rate that could be targeted for programmes of training in cardiopulmonary resuscitation and automated external defibrillator use.

Race, ethnicity, and the risk of sudden death<sup/>

Sudden cardiac death (SCD) is a major cause of death worldwide, with an estimated U.S. annual incidence of 350,000 [1]. This review will examine the influence of race and ethnicity on SCD burden and risk factors, and review the available literature on resuscitation outcomes and primary prevention of SCD. An improved understanding of associations between race, ethnicity, and SCD may provide clues to mechanisms, lead to improved prevention of SCD, and ultimately reduce racial and ethnic disparities in the burden of SCD.

Out-of-hospital cardiac arrest in the home: Can area characteristics identify at-risk communities in the Republic of Ireland?

Background

Internationally, the majority of out-of-hospital cardiac arrests where resuscitation is attempted (OHCAs) occur in private residential locations i.e. at home. The prospect of survival for this patient group is universally dismal. Understanding of the area-level factors that affect the incidence of OHCA at home may help national health planners when implementing community resuscitation training and services.

Methods

We performed spatial smoothing using Bayesian conditional autoregression on case data from the Irish OHCA register. We further corrected for correlated findings using area level variables extracted and constructed for national census data.

Results

We found that increasing deprivation was associated with increased case incidence. The methodology used also enabled us to identify specific areas with higher than expected case incidence.

Conclusions

Our study demonstrates novel use of Bayesian conditional autoregression in quantifying area level risk of a health event with high mortality across an entire country with a diverse settlement pattern. It adds to the evidence that the likelihood of OHCA resuscitation events is associated with greater deprivation and suggests that area deprivation should be considered when planning resuscitation services. Finally, our study demonstrates the utility of Bayesian conditional autoregression as a methodological approach that could be applied in any country using registry data and area level census data.

Electronic supplementary material

The online version of this article (10.1186/s12942-018-0126-z) contains supplementary material, which is available to authorized users.

The Effect of Rurality on Out-of-Hospital Cardiac Arrest Resuscitation Incidence: An Exploratory Study of a National Registry Utilizing a Categorical Approach

PURPOSE

Variation in incidence is a universal feature of out-of-hospital cardiac arrest (OHCA). One potential source of variation is the rurality of the location where the OHCA incident occurs. While previous work has used a simple binary approach to define rurality, the purpose of this study was to use a categorical approach to quantify the impact of urban-rural classification on OHCA incidence in the Republic of Ireland.

METHODS

The observed versus expected ratio of OHCA incidence where resuscitation was attempted for the period January 1, 2012, to December 31, 2014, was calculated for each of the 3,408 electoral divisions (ED). EDs were then classified into 1 of 6 urban-rural classes. Multilevel modeling was used to test for variation in incidence ratios (IR) across the urban-rural classes.

FINDINGS

A total of 4,755 cases of adult OHCA, not witnessed by Emergency Medical Services, where resuscitation was attempted were included in the study. The number of EDs in each category was as follows: city (n = 477); town (n = 293); near village (n = 182); remote village (n = 84); near rural (n = 1,479); remote rural (n = 893). The IR per ED varied from 0 to 18.38 (EDs, n = 3,408). Multilevel modeling showed that 2.36% of variation in IR was due to urban-rural classification. This dropped to 0.45% when adjusted for ED deprivation score and median distance to an ambulance station. The addition of other explanatory variables did not improve the model.

CONCLUSION

OHCA variation in Ireland is limited and almost fully explained by area-level deprivation and proximity to ambulance stations.

Time Trends and Educational Inequalities in Out-of-Hospital Coronary Deaths in Norway 1995-2009: A Cardiovascular Disease in Norway (CVDNOR) Project

BACKGROUND

Recent time trends and educational gradients characterizing out-of-hospital coronary deaths (OHCD) are poorly described.

METHODS AND RESULTS

We identified all deaths from coronary heart disease occurring outside the hospital in Norway during 1995 to 2009. Time trends were explored using Poisson regression analysis with year as the independent, continuous variable. Information on the highest achieved education was obtained from The National Education Database and classified as primary (up to 10 years of compulsory education), secondary (high school or vocational school), or tertiary (college/university). Educational gradients in OHCD were explored using Poisson regression, stratified by sex and age (<70 and ≥70 years), and results were expressed as incidence rate ratios (IRRs) and 95%CIs. Of 100 783 coronary heart disease deaths, 58.8% were OHCDs. From 1995 to 2009, age-adjusted OHCD rates declined across all education categories (primary, secondary, and tertiary) in younger men (IRR=0.35; 95%CI 0.32-0.38; IRR=0.38; 95%CI 0.35-0.42; IRR=0.33; 95%CI 0.28-0.40), younger women (IRR=0.47; 95% CI 0.40-0.56; IRR=0.55; 95%CI 0.45-0.67; IRR=0.28; 95% CI 0.16-0.47), older men (IRR=0.20; 95%CI 0.19-0.22; IRR=0.20; 95%CI 0.18-0.22; IRR=0.20; 95%CI 0.17-0.23), and older women (IRR=0.26; 95%CI 0.24-0.28; IRR=0.25; 95%CI 0.23-0.28; IRR=0.28; 95%CI 0.22-0.34). Tertiary education was associated with lower risk of OHCD compared to primary education (IRR=0.37; 95%CI 0.35-0.40 in younger men, IRR=0.26; 95%CI 0.22-0.30 in younger women, IRR=0.52; 95%CI 0.49-0.55 in older men, and IRR=0.61; 95%CI 0.57-0.66 in older women). These gradients did not change over time (P interaction=0.25).

CONCLUSIONS

Although OHCD rates declined substantially during 1995 to 2009, they displayed educational gradients that remained constant over time.

Role of risk stratification and genetics in sudden cardiac death

Sudden cardiac death (SCD) is a major public health issue due to its increasing incidence in the general population and the difficulty in identifying high-risk individuals. Nearly 300 000 - 350 000 patients in the United States and 4-5 million patients in the world die annually from SCD. Coronary artery disease and advanced heart failure are the main etiology for SCD. Ischemia of any cause precipitates lethal arrhythmias, and ventricular tachycardia and ventricular fibrillation are the most common lethal arrhythmias precipitating SCD. Pulseless electrical activity, bradyarrhythmia, and electromechanical dissociation also result in SCD. Most SCDs occur outside of the hospital setting, so it is difficult to estimate the public burden, which results in overestimating the incidence of SCD. The insufficiency and limited predictive value of various indicators and criteria for SCD result in the increasing incidence. As a result, there is a need to develop better risk stratification criteria and find modifiable variables to decrease the incidence. Primary and secondary prevention and treatment of SCD need further research. This critical review is focused on the etiology, risk factors, prognostic factors, and importance of risk stratification of SCD.

Presumed Regional Incidence Rate of Out-of-Hospital Cardiac Arrest in Korea

The regional incidence rates of out-of-hospital cardiac arrest (OHCA) were traditionally calculated with the residential population as the denominator. The aim of this study was to estimate the true incidence rate of OHCA and to investigate characteristics of regions with overestimated and underestimated OHCA incidence rates. We used the national OHCA database from 2006 to 2010. The nighttime residential and daytime transient populations were investigated from the 2010 Census. The daytime population was calculated by adding the daytime influx of population to, and subtracting the daytime outflow from, the nighttime residential population. Conventional age-standardized incidence rates (CASRs) and daytime corrected age-standardized incidence rates (DASRs) for OHCA per 100,000 person-years were calculated in each county. A total of 97,291 OHCAs were eligible. The age-standardized incidence rates of OHCAs per 100,000 person-years were 34.6 (95% CI: 34.3-35.0) in the daytime and 24.8 (95% CI: 24.5-25.1) in the nighttime among males, and 14.9 (95% CI: 14.7-15.1) in the daytime, and 10.4 (95% CI: 10.2-10.6) in the nighttime among females. The difference between the CASR and DASR ranged from 35.4 to -11.6 in males and from 6.1 to -1.0 in females. Through the Bland-Altman plot analysis, we found the difference between the CASR and DASR increased as the average CASR and DASR increased as well as with the larger daytime transient population. The conventional incidence rate was overestimated in counties with many OHCA cases and in metropolitan cities with large daytime population influx and nighttime outflow, while it was underestimated in residential counties around metropolitan cities.

The knowledge level of final year undergraduate health science students and medical interns about cardiopulmonary resuscitation at a university teaching hospital of Northwest Ethiopia

BACKGROUND

Cardiopulmonary resuscitation (CPR) is a life-saving technique which is used after cardiopulmonary arrest. Chance of survival after arrest will increase if it is coupled with sufficient knowledge. Final year undergraduate health science students and interns manage many trauma and critically ill patients in our hospital. Even though all students took CPR training in undergraduate course, we sometimes saw difficulties in the resuscitation of patients after cardiopulmonary arrest by undergraduate health professionals. This study was to assess the level of knowledge of undergraduate health science students and medical interns about cardiopulmonary resuscitation.

METHODS

Hospital based cross-sectional study was conducted from February 1 to March 30, 2013. All undergraduate health professionals were included. The mean score of knowledge was compared for sex, original residence and department of the participants by using Student's t test and ANOVA with Scheffe's test. P values <0.05 were considered statistically significant.

RESULTS

Four hundred sixty-one out of 506 students were included in this study with a response rate of 91.1%. The overall mean knowledge score of final year undergraduate health science students and interns was 11.1 (SD=0.2). The mean knowledge scores of nurses, interns, health officer, midwifery, anesthesia and psychiatry nursing students were 9.84 (SD=2.5), 13.34 (SD=2.8), 9.81 (SD=3.0), 8.77 (SD=2.6), 13.31 (SD=2.7) and 8.43 (SD=2.4) respectively.

CONCLUSIONS

The knowledge level of undergraduate health professionals about cardiopulmonary resuscitation was insufficient. Training about CPR for undergraduate health professionals should be emphasized.

Socioeconomic indicators and the risk of acute coronary heart disease events: comparison of population-based data from the United States and Finland

PURPOSE

We wished to determine whether a gradient of association of low socioeconomic status with incidence of coronary heart disease was present in two population-based cohorts, one from United States and the other from Finland.

METHODS

Using data from the Atherosclerosis Risk in Communities (ARIC) cohort and the Finnish FINRISK cohort, we estimated, with Cox proportional hazard regression models, incidence of sudden cardiac death (SCD), non-sudden cardiac death (NSCD), and non-fatal myocardial infarction (NFMI) for strata of income and education (follow-up: 1987-2001). In both cohorts, incidence rates of the three outcomes increased across all socioeconomic status exposure categories.

RESULTS

Low education was associated with increased hazard of NFMI in both cohorts and with increased risk of SCD among ARIC women. Low income was significantly associated with increased hazard of all three outcomes among ARIC women and with increased hazard of cardiac death among ARIC men. In FINRISK, low income was significantly associated with increased risk of SCD only. Risk of SCD in the low income categories was similar for both cohorts. Smoking, alcohol consumption, and race (ARIC only) did not appreciably alter effect estimates in either cohort.

CONCLUSIONS

Indices of low SES show similar associations with increased risk of cardiac events in Finland and in United States.

Socioeconomic status and incidence of sudden cardiac arrest

BACKGROUND

Low socioeconomic status is associated with poor cardiovascular health. We evaluated the association between socioeconomic status and the incidence of sudden cardiac arrest, a condition that accounts for a substantial proportion of cardiovascular-related deaths, in seven large North American urban populations.

METHODS

Using a population-based registry, we collected data on out-of-hospital sudden cardiac arrests occurring at home or at a residential institution from Apr. 1, 2006, to Mar. 31, 2007. We limited the analysis to cardiac arrests in seven metropolitan areas in the United States (Dallas, Texas; Pittsburgh, Pennsylvania; Portland, Oregon; and Seattle-King County, Washington) and Canada (Ottawa and Toronto, Ontario; and Vancouver, British Columbia). Each incident was linked to a census tract; tracts were classified into quartiles of median household income.

RESULTS

A total of 9235 sudden cardiac arrests were included in the analysis. For all sites combined, the incidence of sudden cardiac arrestin the lowest socioeconomic quartile was nearly double that in the highest quartile (incidence rate ratio [IRR] 1.9, 95% confidence interval [CI] 1.8-2.0). This disparity was greater among people less than 65 years old (IRR 2.7, 95% CI 2.5-3.0) than among those 65 or older (IRR 1.3, 95% CI 1.2-1.4). After adjustment for study site and for population age structure of each census tract, the disparity across socioeconomic quartiles for all ages combined was greater in the United States (IRR 2.0, 95% CI 1.9-2.2) than in Canada (IRR 1.8, 95% CI 1.6-2.0) (p<0.001 for interaction).

INTERPRETATION

The incidence of sudden cardiac arrest at home or at a residential institution was higher in poorer neighbourhoods of the US and Canadian sites studied, although the association was attenuated in Canada. The disparity across socioeconomic quartiles was greatest among people younger than 65. The association between socioeconomic status and incidence of sudden cardiac arrest merits consideration in the development of strategies to improve survival from sudden cardiac arrest, and possibly to identify opportunities for prevention.

Sudden cardiac death: epidemiology and risk factors

Sudden cardiac death (SCD) is an important public-health problem with multiple etiologies, risk factors, and changing temporal trends. Substantial progress has been made over the past few decades in identifying markers that confer increased SCD risk at the population level. However, the quest for predicting the high-risk individual who could be a candidate for an implantable cardioverter-defibrillator, or other therapy, continues. In this article, we review the incidence, temporal trends, and triggers of SCD, and its demographic, clinical, and genetic risk factors. We also discuss the available evidence supporting the use of public-access defibrillators.

Epidemiology of sudden cardiac death: clinical and research implications

The current annual incidence of sudden cardiac death in the United States is likely to be in the range of 180,000 to 250,000 per year. Coinciding with the decreased mortality from coronary artery disease, there is evidence pointing toward a significant decrease in rates of sudden cardiac death in the United States during the second half of the 20th century. However, the alarming rise in prevalence of obesity and diabetes in the first decade of the new millennium both in the United States and worldwide, would indicate that this favorable trend is unlikely to persist. We are likely to witness a resurgence of coronary artery disease and heart failure, as a result of which sudden cardiac death will have to be confronted as a shared and indiscriminate, worldwide public health problem. There is also increasing recognition of the fact that discovery of meaningful and relevant risk stratification and prevention methodologies will require careful prospective community-wide analyses, with access to large archives of DNA, serum, and tissue that link with well-phenotyped databases. The purpose of this review is to summarize current knowledge of sudden cardiac death epidemiology. We will discuss the significance and strengths of community-wide evaluations of sudden cardiac death, summarize recent observations from such studies, and finally highlight specific potential predictors that warrant further evaluation as determinants of sudden cardiac death in the general population.

Social and demographic predictors of no transport prior to premature cardiac death: United States 1999-2000

BACKGROUND

In the United States, over one-third of premature cardiac deaths occur outside of a hospital, without any transport prior to death. Transport prior to death is a strong, valid indicator of help-seeking behavior. We used national vital statistics data to examine social and demographic predictors of risk of no transport prior to cardiac death. We hypothesized that persons of lower social class, immigrants, non-metropolitan residents, racial/ethnic minorities, men, and younger decedents would be more likely to die prior to transport.

METHODS

Our study population consisted of adult residents of the United States, aged 25 to 64 years, who died from heart disease during 1999-2000 (n = 242,406). We obtained transport status from the place of death variable on the death certificate. The independent effects of social and demographic predictor variables on the risk of a cardiac victim dying prior to transport vs. the risk of dying during or after transport to hospital were modeled using logistic regression.

RESULTS

Results contradicted most of our a priori hypotheses. Persons of lower social class, immigrants, most non-metropolitan residents, and racial/ethnic minorities were all at lower risk of dying prior to transport. The greatest protective effect was found for racial/ethnic minority decedents compared with whites. The strongest adverse effect was found for marital status: the risk of dying with no transport was more than twice as high for those who were single (OR 2.35; 95% CI 2.29-2.40) or divorced (OR 2.29; 95% CI 2.24-2.34), compared with married decedents. Geographically, residents of the Western United States were at a 47% increased risk of dying prior to transport compared with residents of the metropolitan South.

CONCLUSION

Our results suggest that marital status, a broad marker of household structure, social networks, and social support, is more important than social class or race/ethnicity as a predictor of access to emergency medical services for persons who suffer an acute cardiac event. Future research should focus on ascertaining "event histories" for all acute cardiac events that occur in a community, with the goal of identifying the residents most susceptible to cardiac fatalities prior to medical intervention and transport.

Incidence of sudden cardiac arrest is higher in areas of low socioeconomic status: A prospective two year study in a large United States community

BACKGROUND

A potential effect of socioeconomic status on occurrence of sudden cardiac arrest in the community is likely, but has not been evaluated fully.

METHODS

All cases of sudden cardiac arrest in Multnomah County Oregon (population 660,486; February 2002-January 2004) were identified prospectively and categorized by census tract based on the address of residence and specific geographic location of occurrence of cardiac arrest. Each census tract was assigned to quartiles of median income, poverty level, median home value, and educational attainment.

RESULTS

Of 714 cases (annual incidence 54 per 100,000), 697 (98%) had residential addresses that matched a county census tract successfully. For each socioeconomic status measure, the incidence of cardiac arrest was 30-80% higher in the lowest compared to the highest socioeconomic status census tracts. Annual incidence in census tracts in the lowest compared to the highest quartiles of median home value was 60.5 versus 35.1 per 100,000 (RR 1.7, 95% CI 1.4-2.2). This gradient was exaggerated significantly for age<65 years (34.5 versus 15.1 per 100,000, RR 2.3, 95% CI 1.6-3.3). Identical trends were observed for sudden cardiac arrest based on location, with 60% of all cases and 66% of cases age<65 years occurring in the two quartiles with lowest socioeconomic status.

CONCLUSIONS

Low neighborhood socioeconomic status was associated with a significantly higher incidence of sudden cardiac arrest based on address of residence as well as location of cardiac arrest. For effective deployment of strategies for community-based prevention such as the automated external defibrillator, neighborhood socioeconomic status is likely to be an important consideration.