Hospital and emergency department factors associated with variations in missed diagnosis and costs for patients age 65 years and older with acute myocardial infarction who present to emergency departments

Objectives The objective was to measure the variation in missed diagnosis and costs of care for older acute myocardial infarction (AMI) patients presenting to emergency departments (EDs) and to identify the hospital and ED characteristics associated with this variation. Methods Using 2004–2005 Medicare inpatient and outpatient records, the authors identified a cohort of AMI patients age 65 years and older who presented to the ED for initial care. The primary outcome was missed diagnosis of AMI, i.e., AMI hospital admission within 7 days of an ED discharge for a condition suggestive of cardiac ischemia. Costs were defined as Medicare hospital payments for all services associated with and immediately resulting from the ED evaluation. The effect of ED and hospital characteristics on quality and costs were estimated using multilevel models with hospital random effects. Results There were 371,638 AMI patients age 65 and older included in the study, of whom 4,707 were discharged home from their initial ED visits and subsequently admitted to the hospital. The median unadjusted hospital-level missed diagnosis percentage was 0.52% (interquartile range [IQR] = 0 to 3.45%). ED characteristics protective of adverse outcomes include higher ED chest pain acuity (adjusted odds ratio [aOR] = 0.23, 99% confidence interval [CI] = 0.19 to 0.27) and American Board of Emergency Medicine (ABEM) certification (aOR = 0.60, 99% CI = 0.50 to 0.73). Protective hospital characteristics include larger hospital size (aOR = 0.46, 99% CI = 0.37 to 0.57) and academic status (aOR = 0.74, 99% CI = 0.58 to 0.94). All of these characteristics were associated with higher costs as well. Conclusions The proportion of missed AMI diagnoses and cost of care for patients age 65 years and older presenting to EDs with AMI varies across hospitals. Hospitals with more board-certified emergency physicians (EPs) and higher average acuity are associated with significantly higher quality. All hospital characteristics associated with better ED outcomes are associated with higher costs. Resumen Objetivos El objetivo fue la medicion conjunta de la variacion en el diagnostico erroneo y los costes de la atencion del infarto agudo de miocardio (IAM) en los pacientes mayores atendidos en los servicios de urgencias (SU) e identificar las caracteristicas del SU y del hospital asociadas con esta variacion. Metodologia Se identifico una cohorte de pacientes de 65 o mas anos con IAM que se atendieron inicialmente en un SU usando las historias de pacientes ingresados y dados de alta de Medicare 2004–2005. El resultado principal fue el diagnostico erroneo de IAM (por ejemplo: ingreso en el hospital por IAM en los primeros 7 dias tras un alta del SU por una patologia sugestiva de isquemia cardiaca). Los costes se definieron como pagos de Medicare al hospital por todos los servicios asociados con, e inmediatamente derivados de la evaluacion del SU. El impacto de las caracteristicas del SU y del hospital en la calidad y los costes se estimaron mediante modelos multinivel con efectos aleatorios del hospital. Resultados Hubo 371.638 pacientes de 65 o mas anos con IAM incluidos en el estudio, de los cuales 4.707 fueron dados de alta tras la visita inicial al SU y posteriormente ingresados en un hospital. El porcentaje mediano no ajustado al nivel del hospital de diagnostico erroneo fue de un 0,52% (rango intercuartilico [RIC] 0 a 3,45%). Las caracteristicas protectoras del SU del SU protectoras de resultados adversos incluyeron una mayor gravedad del dolor toracico en el SU (odds > ratio ajustada [ORa] 0,23, intervalo de confianza [IC] 99% = 0,19 a 0,27), y la certificacion del (urgenciologo) (ORa 0,60, IC 99% = 0,50 a 0,73). Las caracteristicas protectoras del hospital incluyeron un hospital de mayor tamano (ORa 0,46, IC 99% = 0,37 a 0,57) y universitario (ORa 0,74, IC 99% = 0,58 a 0,94). Todas estas caracteristicas se asociaron tambien con mayores costes. Conclusiones La proporcion de diagnostico erroneo de IAM y los costes de la atencion para los pacientes de 65 o mas anos que se atienden en los SU varian entre los hospitales. El hospital con mas (urgenciologos) certificados y mayor promedio de gravedad asocia significativamente mayor calidad. Todas las caracteristicas del hospital se asociaron con mejores resultados del SU y con mayores costes.