National trends in the prevalence and recurrence of anaphylaxis across all ages: The role of neighborhood deprivation and comorbidity (2002-2019)

Abstract

Background: Understanding the trends of anaphylaxis and risk factors associated with its recurrence is essential for the effective management and prevention of this condition.

Objective: This study aimed to analyze the prevalence trends of anaphylaxis and identify risk factors for recurrence, with a focus on the influence of neighborhood deprivation and comorbidities, across all age groups.

Methods: We conducted a retrospective administrative cohort study on anaphylaxis utilizing the National Health Insurance-National Sample Cohort (NHIS-NSC) database in Korea (2002-2019). Anaphylaxis was defined with ICD-10 codes for the diagnosis combined with prescription codes. The Neighborhood Deprivation Index was used to identify the risk of recurrent anaphylaxis. Trends in the annual prevalence and recurrence of anaphylaxis were assessed through joinpoint regression and Cox proportional hazard models.

Results: Out of the 1,137,861 individuals studied, 37,012 (3.25%) cases of anaphylaxis were identified. Among these, 5783 individuals (15.6%) experienced a recurrence, half of them experiencing it within the first year after the initial episode. The highest incidence of anaphylaxis was observed in children and adolescents, followed by middle-aged adults. A rapid increase in anaphylaxis cases was observed from 2002 to 2006 (Annual Percentage Change [APC], 33.2), followed by a more gradual increase until 2013 (APC, 12.8), and a stable trend from 2013 to 2019 (APC, 0.61). Males and adult age groups exhibited an increased risk of recurrence. Living in an area with neighborhood deprivation and the presence of comorbid conditions were associated with increased recurrence risk.

Conclusions: The increasing prevalence of anaphylaxis and its association with certain risk factors calls for targeted intervention. Addressing neighborhood deprivation and comorbid conditions may aid in reducing the recurrence and overall burden of anaphylaxis.

Keywords: Anaphylaxis; Area deprivation index; Epidemiology; Recurrent.

Fig. 1

Schematic representation of the study population.

Fig. 2

Age-adjusted prevalence of anaphylaxis by sex from 2002 to 2019, categorized as (A) overall, (B) male, and (C) female. Abbreviations: PY, person year. In each graph, the blue, green, red, and light blue solid lines represent the age-adjusted trend over the period. The background and solid color change with a significant shift in the prevalence trend. The filled squares with numbers indicate the age-adjusted prevalence of anaphylaxis per 10,000 person-years.

Fig. 3

Prevalence of anaphylaxis from 2002 to 2019 by age groups. Abbreviations: PY, person year. A filled circle represents the prevalence of anaphylaxis per 10,000 person-years, while the shaded area indicates the standard error.

Fig. 4

Demographic and clinical risk factors associated with the recurrence of anaphylaxis. The hazard ratio was calculated for the risk of recurrent anaphylaxis episodes for each characteristic and compared to the reference group by tracking the person-years for both single and recurrent anaphylaxis episodes within each group. The filled circle indicates the adjusted hazard ratio for the recurrence of anaphylaxis, and the black line indicates the corresponding 95% confidence interval. All analyses were adjusted for sex, age, and calendar year at the time of the initial anaphylaxis event, with the independent variable excluded from these adjustments. The Charlson Comorbidity Score was used to assess chronic conditions, including hypertension, diabetes, hyperlipidemia, osteoporosis, and chronic renal failure, using ICD-10 codes.