Incidence of Fatal Anaphylaxis: A Systematic Review of Observational Studies.

BACKGROUND: Fatal anaphylaxis is very rare, with an incidence ranging from 0.5 to 1 deaths per million person-years. OBJECTIVE: Based on a systematic review, we aimed to explain differences in the reported incidence of fatal anaphylaxis based on the methodological and demographic factors addressed in the various studies. METHODS: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for relevant retrospective and prospective cohort studies and registry studies that had assessed the anaphylaxis mortality rate for the population of a country or for an administrative region. The research strategy was based on combining the term "anaphylaxis" with "death", "study design", and "main outcomes" (incidence). RESULTS: A total of 46 studies met the study criteria and included 16,541 deaths. The range of the anaphylaxis mortality rate for all causes of anaphylaxis was 0.002-2.51 deaths per million person-years. Fatal anaphylaxis due to food (range 0.002-0.29) was rarer than deaths due to drugs (range 0.004-0.56) or Hymenoptera venom (range 0.02-0.61). The frequency of deaths due to anaphylaxis by drugs increased during the study period (IRR per year, 1.02; 95%CI, 1.00-1.04). We detected considerable heterogeneity in almost all of the meta-analyses carried out. CONCLUSION: The incidence of fatal anaphylaxis is very low and differs according to the various subgroups analyzed. The studies were very heterogeneous. Fatal anaphylaxis due to food seems to be less common than fatal anaphylaxis due to drugs or Hymenoptera venom.

Incidence of Fatal Anaphylaxis A Systematic Review of Observational Studies

Background: Fatal anaphylaxis is very rare, with an incidence ranging from 0.5 to 1 deaths per million person-years. Objective: Based on a systematic review, we aimed to explain differences in the reported incidence of fatal anaphylaxis based on the methodological and demographic factors addressed in the various studies. Methods: We searched PubMed/MEDLINE, EMBASE, and the Web of Science for relevant retrospective and prospective cohort studies and registry studies that had assessed the anaphylaxis mortality rate for the population of a country or for an administrative region. The research strategy was based on combining the term “anaphylaxis” with “death”, “study design”, and “main outcomes” (incidence). Results: A total of 46 studies met the study criteria and included 16,541 deaths. The range of the anaphylaxis mortality rate for all causes of anaphylaxis was 0.002-2.51 deaths per million person-years. Fatal anaphylaxis due to food (range 0.002-0.29) was rarer than deaths due to drugs (range 0.004-0.56) or Hymenoptera venom (range 0.02-0.61). The frequency of deaths due to anaphylaxis by drugs increased during the study period (IRR per year, 1.02; 95%CI, 1.00-1.04). We detected considerable heterogeneity in almost all of the meta-analyses carried out. Conclusion: The incidence of fatal anaphylaxis is very low and differs according to the various subgroups analyzed. The studies were very heterogeneous. Fatal anaphylaxis due to food seems to be less common than fatal anaphylaxis due to drugs or Hymenoptera venom (AU)

Antecedentes: La muerte por anafilaxia es un evento muy excepcional, con una incidencia que varía de 0,5 a 1 muerte por millón de personas/año. Objetivo: Usando las técnicas de una revisión sistemática, nuestro objetivo ha sido explicar las diferencias en la incidencia informada de la muerte por anafilaxia atendiendo a diversos factores metodológicos y demográficos empleados en los diversos estudios de la revisión. Métodos: Se realizaron búsquedas en PubMed/MEDLINE, EMBASE y Web of Science, con el fin de obtener estudios de cohortes y registros prospectivos y retrospectivos relevantes que hubieran evaluado la tasa de muerte por anafilaxia en la población de un país o una región administrativa. La estrategia de investigación se basó en combinar “anafilaxia” con “muerte”, “diseño del estudio” y “resultados principales” (incidencia). Resultados: Un total de 46 estudios cumplieron con los criterios del estudio. Los estudios incluyeron 16.541 muertes. El rango de la tasa de mortalidad por anafilaxia para todas las causas de anafilaxia fue de 0,002 a 2,51 muertes por millón de personas/año. La anafilaxia mortal debida a los alimentos (rango 0,002-0,29) fue más rara que las muertes debidas a medicamentos (rango 0,004-0,56) o veneno de himenópteros (rango 0,02-0,61). La frecuencia de muertes por anafilaxia por fármacos aumentó durante el período de estudio (IRR por año, 1,02; IC del 95%: 1,00-1,04). Se detectó una heterogeneidad considerable en casi todos los metaanálisis realizados. Conclusión: La incidencia de anafilaxia mortal es muy baja y difiere según los distintos subgrupos analizados. Los estudios fueron muy heterogéneos. La muerte por anafilaxia debida a alimentos parece ser menos común que la anafilaxia mortal debida a fármacos o por veneno de himenópteros (AU)

Clinical Profile of Patients With Severe Anaphylaxis Hospitalized in the Spanish Hospital System: 1997-2011.

BACKGROUND AND OBJECTIVE: Studies assessing the severity of anaphylaxis lack a comprehensive approach to collecting data on comorbidities that may worsen prognosis. Objective: Using the Elixhauser score (a systematic index associated with longer stay, hospital charges, and mortality), we determined which comorbidities were associated with more severe anaphylaxis. METHODS: We based our study on the Spanish Ministry of Health database of hospital discharges in Spain between 1997 and 2011. We constructed logistic regression models in which the dependent variables were outcomes related to greater severity (death, cardiac arrest, need for invasive mechanical ventilation or vasopressor drugs, admission to the intensive care unit, and length of stay) and the independent variables were the 30 comorbidities that comprise the Elixhauser score, age, sex, and main causes of anaphylaxis. RESULTS: We found that a higher risk of severe anaphylaxis was associated (3 or more logistic regressions) with age >50 years or having experienced cardiac arrhythmia, coagulation disorder, associated fluid-electrolyte imbalance, chronic pulmonary disease, or Echinococcus anaphylaxis. Likewise, in the adjusted analysis, a higher Elixhauser score was associated with most of the outcomes analyzed for severity of anaphylaxis. CONCLUSIONS: Cardiovascular and respiratory diseases increase the severity of anaphylaxis, and the resulting poor health status (represented as a higher Elixhauser score) is associated with more severe anaphylaxis.

Clinical profile of patients with severe anaphylaxis hospitalized in the Spanish Hospital System: 1997-2011

Background: Studies assessing the severity of anaphylaxis lack a comprehensive approach to collecting data on comorbidities that may worsen prognosis. Objective: Using the Elixhauser score (a systematic index associated with longer stay, hospital charges, and mortality), we determined which comorbidities were associated with more severe anaphylaxis. Methods: We based our study on the Spanish Ministry of Health database of hospital discharges in Spain between 1997 and 2011. We constructed logistic regression models in which the dependent variables were outcomes related to greater severity (death, cardiac arrest, need for invasive mechanical ventilation or vasopressor drugs, admission to the intensive care unit, and length of stay) and the independent variables were the 30 comorbidities that comprise the Elixhauser score, age, sex, and main causes of anaphylaxis. Results: We found that a higher risk of severe anaphylaxis was associated (3 or more logistic regressions) with age >50 years or having experienced cardiac arrhythmia, coagulation disorder, associated fluid-electrolyte imbalance, chronic pulmonary disease, or Echinococcus anaphylaxis. Likewise, in the adjusted analysis, a higher Elixhauser score was associated with most of the outcomes analyzed for severity of anaphylaxis. Conclusions: Cardiovascular and respiratory diseases increase the severity of anaphylaxis, and the resulting poor health status (represented as a higher Elixhauser score) is associated with more severe anaphylaxis (AU)

Antecedentes: Los estudios que recogen datos sobre comorbilidades que empeoran la gravedad de la anafilaxia, carecen de un acercamiento exhaustivo. Objetivo: Usando la puntuación de Elixhauser (un sistema de puntuación asociado con mayor estancia hospitalaria, mayor gasto hospitalario y muerte), establecimos que comorbilidades fueron asociadas con anafilaxia grave. Métodos: Usamos para el estudio la base de datos de altas hospitalarias del Ministerio Español de Sanidad, entre 1997 a 2011. Se obtuvo varios modelos de regresión logística, en las cuales las variables dependientes fueron desenlaces relacionados con eventos asociados habitualmente a una gran gravedad de los episodios (muerte, parada cardio-respiratoria, necesidad de uso de ventilación mecánica invasiva o medicamentos vaso-presores, ingreso en la Unidad de Cuidados Intensivos y duración de la estancia) y las variables independientes fueron las 30 comorbilidades que comprenden la puntuación Elixhauser, junto con edad, sexo y las grandes causas de anafilaxia. Resultados: Encontramos que un mayor riesgo para anafilaxia grave estuvo asociado (3 o más regresiones logísticas con significación estadística) con una edad de más de 50 años, o haber experimentado arritmias cardiacas, alteraciones de la coagulación, disbalance hidro-electrolítico, enfermedad pulmonar crónica o anafilaxia por Echinococcus. Así mismo, en un análisis ajustado, una puntuación mayor del sistema Elixhauser se asoció con la mayoría de las variables de desenlace usadas para analizar la gravedad de la anafilaxia. Conclusiones: Enfermedades cardio-vasculares y respiratorias incrementan la gravedad de la anafilaxia y un mal estado de salud (representado por mayores puntuaciones del Sistema de puntuación de Elixhauser) se asocian con mayor gravedad de la anafilaxia (AU)