There are more than 356,000 out-of-hospital cardiac arrests (OHCA) annually in the U.S., nearly 90% of them fatal, according to the American Heart Association’s newly released Heart Disease and Stroke Statistics - 2018 Update. According to the report, the annual incidence of EMS-assessed non-traumatic OHCA in people of any age is estimated to be 356,461.
There are a number of ongoing challenges to understanding the epidemiology of cardiac arrest in the U.S. Despite being a leading cause of death, there are currently no nationwide standards for surveillance to monitor the incidence and outcomes of cardiac arrest. Thus, registries and clinical trials are used to provide best estimates.
Following are highlights from the report:
- Estimates suggest the incidence of OHCA among adults is 347,322.
- Overall, survival to hospital admission after EMS-treated non-traumatic cardiac OHCA was 29%, with higher survival rates in public places (39.5%) and lower survival rates in homes/residences (27.5%) and nursing homes (18.2%)
- Survival to hospital discharge was 10.8% among adults (9% with good neurological function).
- Large regional variations in survival to hospital discharge (range, 3.4%-22%) and survival with functional recovery (range, 0.8%-20.1%) are observed in 132 counties in the U.S. Variations in the rates of layperson CPR explained much of this variation.
- Among adults treated by EMS, 25% had no symptoms before the onset of arrest.
- The majority of OHCA’s occur at a home or residence (68.5%), followed by public settings (21%) and nursing homes (10.5%).
- Cardiac arrest was witnessed by a bystander in 37% of cases, and an EMS provider in 12% of cases. For 51% of cases, the collapse was not witnessed.
- Among EMS-treated OHCA patients, 19.8% had an initial rhythm (Ventricular Fibrillation or Ventricular Tachycardia) that is shockable by an automated external defibrillator (AED).
- Among 10.9 million registered participants in 40 marathons and 19 half-marathons, the overall incidence of cardiac arrest was 0.54 per 100,000 participants. Those with cardiac arrests were more often male and were running a marathon versus a half-marathon. Among runners with cardiac arrest, 71% died; those who died were younger (39+9) than those who survived 49+10).
|Annual Incidence of EMS-Assessed OHCA|
- Estimates suggest the incidence of EMS-assessed OHCA among children (<18 years of age) is 7,037.
- Survival to hospital discharge was 10.7% among children (8.2% with good neurological function).
- The location of EMS-treated OHCA was at home for 89.5% of children <1 years old, 77% of children 1-12 years old, and 72.9% for children 13-18 years old.
- The most common causes of SCD among young athletes are hypertrophic cardiomyopathy (36%), coronary artery abnormalities (19%), myocarditis (7%), arrhythmogenic right ventricular cardiomyopathy (5%), coronary artery disease (4%), and commotio cordis (3%).
- The incidence of SCD was 0.24 per 100,000 athlete years in high school athletes screened every three years between 1993 and 2012 in Minnesota.
- The incidence of non-traumatic OHCA was 1 per 43,770 athlete participant-years among students 17-24 years old participating in NCAA sports from 2004-2008. The incidence of cardiac arrest was higher among blacks than among whites and among males than among females.
|Characteristics of and Outcomes for OHCA|
|Survival to hospital discharge||10.8||10.7|
|Good functional status at hospital discharge||9||8.2|
- A family history of cardiac arrest in a first-degree relative is associated with an ~2-fold increased risk of cardiac arrest.
- According to 2017 figures from the CDC, SCD appears among the multiple causes of death on 13.5% of death certificates, which suggests that 1 of every 7.4 people in the U.S. will die of SCD. Among adults, the risk of SCD increases exponentially with age.
- Unadjusted survival to hospital discharge after EMS-treated OHCA increased from 10.2% in 2006 to 12.4% in 2015.
- Rates of layperson-initiated CPR and layperson use of AEDs have increased over time. In 2016, laypersons initiated CPR in 40.7% of cases (up from 36.5% in 2006). Laypersons used AEDs in 5.7% of cases (up from 3.2% in 2006).
- Survivors of cardiac arrest experience multiple medical problems including impaired consciousness and cognitive deficits. As many as 18% of OHCA survivors have moderate to severe functional impairment at hospital discharge. Functional recovery continues over the first six to 12 months after OHCA in adults.
Healthcare Utilization and Cost
- The estimated societal burden of SCD in the U.S. was 2 million years of potential life lost for males and 1.3 million potential life lost for females, accounting for 40-50% of the years of potential life lost from all cardiac diseases.
- Among males, estimated deaths attributed to SCD exceeded all other individual causes of death, including lung cancer, accidents, chronic lower respiratory disease, cerebrovascular disease, diabetes mellitus, prostate cancer, and colorectal cancer.
Awareness and Treatment
- The median annual CPR training rate for U.S. counties was 2.39%, based on data from the AHA, American Red Cross and the Health & Safety Institute, the largest providers of CPR training in the U.S. The prevalence of reported current CPR training was 18%, and the prevalence of having CPR training at some point was 65%. Training rates were lower in rural areas, areas with high proportions of black or Hispanic residents, and counties with lower median household incomes.
- The absence of standards for monitoring and reporting the incidence and outcomes of cardiac arrest remains a barrier to population research in the U.S. Increasing the rigor of reporting cardiac arrest will improve understanding of the epidemiology of this syndrome.
ORIGINAL SOURCE: American Heart Association; Summary compiled by Mary Newman, MS, Sudden Cardiac Arrest Foundation