Fatal Food Anaphylaxis Research Articles

Using NHS Data to Monitor Trends in the Occurrence of Severe, Food-Induced Allergic Reactions Work Package 1

People with food allergies may experience food allergic reactions due to accidental exposure. These reactions are commonly categorised as non-severe, fatal food anaphylaxis and near-fatal food anaphylaxis. Non-severe allergic reactions to food are more common with an incidence of up to 1,000 times greater than fatal food-related anaphylaxis. However, obtaining accurate data relating to the circumstances under which these reactions occurred is challenging under the current diagnosis coding system used in the National Health Service (NHS). This project addressed two key questions: 1. What are the trends in the occurrence of food hypersensitivity (FHS) reactions and their consequences in terms of healthcare encounters (both to hospital and primary care)? 2. What are the circumstances surrounding severe, life-threatening reactions to food? Approach The researchers used existing NHS datasets (relating to Hospital Admissions, Accident & Emergency visits, Critical Care admissions and Primary care visits) to evaluate healthcare encounters due to food hypersensitivity over the study period. Patient pathways through the healthcare system were also assessed by linking these different datasets. Key Results • Food-induced anaphylaxis represented 29.4% of reported anaphylaxis. admissions, and increased significantly from 1.23 to 4.02 admissions per 100,000 population per annum over the study period. • However, despite an annual increase of 5.7% in hospitalisation for food-induced anaphylaxis between 1998 and 2018, the case fatality rate (proportion of hospital admissions associated with a fatal outcome) more than halved, from 0.7% in 1998 to less than 0.3% in 2018. • 152 deaths were identified during the study period where the cause was very likely to have been food-induced anaphylaxis. • At least 86 (46%) fatalities were triggered by peanut or tree nuts. • Cows’ milk was reported to be the most common cause of fatal anaphylaxis in children aged under 16 years. • Using data from England for the period 2008-2018, the prevalence of food allergy ranged from 4% in preschool-aged children (under 5 years), 1-2% in school-aged children and young people (5 to 20 years) and 0.9% in adults. Although the same methods were used throughout the study period, the statistics presented may be prone to limitations such as miscoding and incomplete datasets. • Prescription of adrenaline auto-injector devices (AAI) are an important risk management intervention in people at risk of food-induced anaphylaxis. However, there is significant under-prescribing of AAI. Data showed that 40% of individuals with prior food-induced anaphylaxis were not prescribed AAI and at least 59% did not have AAI on repeat prescription. • Most healthcare visits for food allergy occurred in general practice. Less than 3% of individuals with a diagnosis of food allergy attended Accident and Emergency during the study period, 2008-2018. Therefore, using hospital data in isolation to analyse patterns of health service utilisation with respect to FHS may not provide a comprehensive overview.

Using NHS Data to Monitor Trends in the Occurrence of Severe, Food-Induced Allergic Reactions Work Package 2

People with food allergies may experience food allergic reactions due to accidental exposure. These reactions are commonly categorised as non-severe, fatal food anaphylaxis and near-fatal food anaphylaxis. Non-severe allergic reactions to food are more common with an incidence of up to 1,000 times greater than fatal food-related anaphylaxis. However, obtaining accurate data relating to the circumstances under which these reactions occurred is challenging under the current diagnosis coding system used in the National Health Service (NHS). This project addressed two key questions: 1. What are the trends in the occurrence of food hypersensitivity (FHS) reactions and their consequences in terms of healthcare encounters (both to hospital and primary care)? 2. What are the circumstances surrounding severe, life-threatening reactions to food? Approach • A UK arm of NORA was established using the same online platform as the existing European Registry. • Participation of healthcare professionals and/or patients to enter relevant information was co-ordinated by BSACI in conjunction with the Paediatric Emergency Research in the United Kingdom Ireland (PERUKI) network. • Different versions of the questionnaire were developed to increase response rates: (1) a comprehensive form mapped to existing NORA data fields for completion by Healthcare Professionals in the non-acute setting; (2) a shorter form with key data fields to increase data reporting in more pressured, acute healthcare settings; and (3) a form for completion by patients or their parent/guardian. Key Results The launch of the UK anaphylaxis registry faced delays and was impacted by significant pressures on NHS services due to the COVID-19 pandemic. This led to a lower than anticipated uptake of the Registry by clinics and Accident & Emergency departments. As a result, only a minority of accidental reactions (less than 5%) were captured in the registry, almost all in children and young people under age 18 years. Some indicative results of this analysis are the following: • 213 cases reported to be due to a food trigger and of these, 208 occurred in children/young people aged 18 years or under. • Common food triggers were peanut, tree nuts (especially cashew), cow’s milk/dairy and hen’s egg. • 47% of reactions occurred after consumption of prepacked food products and in at least 59% of these cases, the allergen was declared as an actual ingredient. Further work would be needed to understand how to optimise reporting of data, for example by reducing the time burden for completion by clinicians and patients.

Separating Fact from Fiction in the Diagnosis and Management of Food Allergy

Separating Fact from Fiction in the Diagnosis and Management of Food Allergy

Food anaphylaxis in the United Kingdom: analysis of national data, 1998-2018

ObjectiveTo describe time trends for hospital admissions due to food anaphylaxis in the United Kingdom over the past 20 years.DesignAnalysis of national data, 1998-2018.SettingData relating to hospital admissions for anaphylaxis...

Anaphylaxis in adolescents.

The frequency of hospitalization for anaphylaxis has increased over the last 20 years across Europe, Australia, and North America, particularly, for food and medication triggers. Adolescents show the highest risk for morbidity and fatality from food-induced anaphylaxis, yet there is little high-quality evidence addressing the reasons for this disproportionate vulnerability. Recent data seem to suggest a possible increasing burden of food-induced anaphylaxis among adolescents. Trends in anaphylaxis mortality are stable in North America and the United Kingdom, but not in Australia where the incidence of fatal anaphylaxis has recently doubled. The age distribution of fatal anaphylaxis varies according to the nature of the culprit trigger, with data suggesting an age-related predisposition to fatal food anaphylaxis in adolescents and young adults. Adolescence represents a critical phase of transition when rapid and substantial physical, emotional, and social changes occur. Therefore, adolescents show challenges in self-management that are different from other age groups, contributing to a higher risk of poor anaphylaxis outcomes. The purpose of this review is to summarize recent data on epidemiology and elicitors of anaphylaxis in adolescents and to address currently known barriers and potential facilitators to self-management of anaphylaxis in this vulnerable age group.

Anaphylaxis in Children: Epidemiology, Risk Factors and Management.

Anaphylaxis is defined as a serious, generalized or systemic allergic reaction that is rapid in onset and may cause death. It is unpredictable and can be the result of various allergic triggers including food, insect venom and medication. The European Anaphylaxis Registry confirmed food as the major elicitor of anaphylaxis in children, specifically hen's egg, cow's milk and nuts. It has been reported that the incidence of anaphylaxis is on the rise. In the US, there is a continued trend of increasing food-induced anaphylaxis hospitalizations among children, which is supported by nationally representative data. Anaphylaxis can occur both in the home and outdoors and can be life-threatening, however, fatalities are a rare occurrence. A recent systematic review and meta-analysis reported that fatal food anaphylaxis is rarer than accidental death in the general population. Studies of fatal and near-fatal allergic reactions have identified potential risk factors for fatalities and have provided important information that may help minimize future risk. Following confirmation of the relevant allergen trigger, prevention of anaphylaxis is through strict avoidance of the allergen and optimal management of existing co-morbidities. The cornerstone in the successful management of anaphylaxis is early recognition of signs and symptoms and the prompt administration of intramuscular adrenaline. Patients and their families need to be well educated on how to manage potential anaphylactic reactions with training in the use of adrenaline auto-injectors and personalized emergency management plans. Healthcare professionals must be familiar with this clinical emergency and able to respond to anaphylaxis in a timely and appropriate manner.

Fatal Anaphylaxis: Mortality Rate and Risk Factors

Up to 5% of the US population has suffered anaphylaxis. Fatal outcome is rare, such that even for people with known venom or food allergy, fatal anaphylaxis constitutes less than 1% of total mortality risk. The incidence of fatal anaphylaxis has not increased in line with hospital admissions for anaphylaxis. Fatal drug anaphylaxis may be increasing, but rates of fatal anaphylaxis to venom and food are stable. Risk factors for fatal anaphylaxis vary according to cause. For fatal drug anaphylaxis, previous cardiovascular morbidity and older age are risk factors, with beta-lactam antibiotics, general anesthetic agents, and radiocontrast injections the commonest triggers. Fatal food anaphylaxis most commonly occurs during the second and third decades. Delayed epinephrine administration is a risk factor; common triggers are nuts, seafood, and in children, milk. For fatal venom anaphylaxis, risk factors include middle age, male sex, white race, cardiovascular disease, and possibly mastocytosis; insect triggers vary by region. Upright posture is a feature of fatal anaphylaxis to both food and venom. The rarity of fatal anaphylaxis and the significant quality of life impact of allergic conditions suggest that quality of life impairment should be a key consideration when making treatment decisions in patients at risk for anaphylaxis.

Community healthcare professionals overestimate the risk of fatal anaphylaxis for food allergic children

Fatal food anaphylaxis is rare, but a major concern for people with food allergy and their carers. We evaluated whether community healthcare professionals accurately estimate risk of fatal anaphylaxis for food allergic children, and whether accurate risk estimation is related to competence in recognizing and managing anaphylaxis. We enrolled 90 community healthcare professionals in a cross-sectional survey- 30 primary care nurses, 30 school first aiders, 30 community pharmacists. Participant risk estimates for fatal and non-fatal anaphylaxis, and all-cause fatalities, were measured using a risk ladder. Participant anaphylaxis knowledge was assessed by questionnaire, and practical skills using a simulated anaphylaxis scenario. In all three groups, participants significantly overestimated the risk of fatal anaphylaxis for food allergic children, by a mean factor of 13.5-fold (95% CI 5.0, 31.6), but did not overestimate non-fatal anaphylaxis risk or all-cause fatality risk. We found no evidence of a relationship between successful adrenaline administration and risk estimation. In conclusion, we have found evidence that community pharmacists, school first aiders and primary care nurses in the UK systematically overestimate the risk of fatal anaphylaxis for a food allergic child. This overestimation may result in increased patient and carer anxiety. Community practitioners who manage childhood food allergy and anaphylaxis need to be educated about the level of risk for fatal anaphylaxis in such children.

Epidemiology of severe anaphylaxis: can we use population-based data to understand anaphylaxis?

The observed increase in incidence of allergic disease in many regions over the past 3 decades has intensified interest in understanding the epidemiology of severe allergic reactions. We discuss the issues in collecting and interpreting these data and highlight current deficiencies in the current methods of data gathering. Anaphylaxis, as measured by hospital admission rates, is not uncommon and has increased in the United Kingdom, the United States, Canada, and Australia over the last 10-20 years. All large datasets are hampered by a large proportion of uncoded, 'unspecified' causes of anaphylaxis. Fatal anaphylaxis remains a rare event, but appears to be increasing for medication in Australia, Canada, and the United States. The rate of fatal food anaphylaxis is stable in the United Kingdom and the United States, but has increased in Australia. The age distribution for fatal food anaphylaxis is different to other causes, with data suggesting an age-related predisposition to fatal outcomes in teenagers and adults to the fourth decade of life. The increasing rates of food and medication allergy (the latter exacerbated by an ageing population) has significant implications for future fatality trends. An improved ability to accurately gather and analyse population-level anaphylaxis data in a harmonized fashion is required, so as to ultimately minimize risk and improve management.

Increases in anaphylaxis fatalities in Australia from 1997 to 2013.

Recent epidemiological studies indicate increases in Australian, UK and US hospital anaphylaxis admission rates. The aim of this study was to determine whether Australian anaphylaxis fatalities are increasing in parallel and to examine the characteristics of fatalities recorded in the National Coronial Information System (NCIS). Time trends in Australian anaphylaxis fatalities were examined using data derived from the Australian Bureau of Statistics (ABS) 1997-2013 and the NCIS 2000-2013, the latter providing additional information to verify cause and identify risk factors. The ABS recorded 324 anaphylaxis fatalities by cause: unspecified (n = 205); medication (n = 52); insect stings/tick bites (n = 41); food (n = 23); and blood products (n = 3). From 1997 to 2013, all-cause fatal anaphylaxis rates increased by 6.2%/year (95% CI: 3.8-8.6%, P < 0.0001) or from 0.054% to 0.099/10(5) population. Fatal food anaphylaxis increased by 9.7%/year (95% CI: 0.25-20%, P = 0.04) and unspecified anaphylaxis deaths by 7.8% (95% CI: 4.6-11.0, P < 0.0001). There was an insignificant change in medication-related fatalities (5.6% increase/year; 95% CI: 0.3% decrease to 11.8% increase, P = 0.06), and sting/bite fatalities remained unchanged. Hospital anaphylaxis admission rates for all-cause, food, unspecified and medication anaphylaxis increased at rates of 8%, 10%, 4.4% and 6.8%/year, respectively. A total of 147 verified NCIS deaths were examined in detail: medication- and sting/bite-related fatalities occurred predominantly in older individuals with multiple comorbidities. Upright posture after anaphylaxis was associated with risk of sudden death (all causes). Seafood (not nuts) was the most common trigger for food-related anaphylaxis deaths. Australian anaphylaxis fatality rates (most causes) have increased over the last 16 years, contrasting with UK- and US-based studies that describe overall lower and static overall anaphylaxis fatality rates (0.047-0.069/10(5) population).

Age As a Risk Factor For Fatal Food-Induced Anaphylaxis: An Analysis Of UK and Australian Fatal Food Anaphylaxis Data

Small case series suggest that teenagers and young adults may be at higher risk of fatal food-induced anaphylaxis than other age groups, but this has not been confirmed in large population-based datasets. We extracted data from national databases for hospital admissions and fatalities due to anaphylaxis in England and Wales for the period 1992-2011, and cross-checked fatalities against a prospective fatal anaphylaxis registry. We examined time trends and age distribution for fatal reactions caused by food, drugs and insect stings, and compared these to equivalent data previously published from Australia. Hospital admissions due to anaphylaxis admissions increased steadily over the time periods studied in both the UK and Australia, but fatality rates have remained stable at around 0.04 (UK) and 0.05 (Aus) cases per 100,000 population per annum. Fatalities and admissions were most common in older people for drug- and insect sting-induced anaphylaxis. For food-triggered reactions, fatalities were most common in teenagers and young adults, in both countries. These findings are not explained by age-related differences in the prevalence of food anaphylaxis requiring hospitalisation. In the UK and Australia, hospitalisations for anaphylaxis have increased, but fatal anaphylaxis has not. Possible explanations include increasing recognition of anaphylaxis, improved management and a real increase in the prevalence of food allergy. Of note, the age-distribution of fatal cases varies significantly according to the nature of the eliciting agent, and raises important questions about the differences in the pathogenesis of anaphylaxis between different triggers.

Incidence of fatal food anaphylaxis in people with food allergy: a systematic review and meta‐analysis

BackgroundFood allergy is a common cause of anaphylaxis, but the incidence of fatal food anaphylaxis is not known. The aim of this study was to estimate the incidence of fatal food anaphylaxis for people with food allergy and relate this to other mortality risks in the general population.MethodsWe undertook a systematic review and meta-analysis, using the generic inverse variance method. Two authors selected studies by consensus, independently extracted data and assessed the quality of included studies using the Newcastle-Ottawa assessment scale. We searched Medline, Embase, PsychInfo, CINAHL, Web of Science, LILACS or AMED, between January 1946 and September 2012, and recent conference abstracts. We included registries, databases or cohort studies which described the number of fatal food anaphylaxis cases in a defined population and time period and applied an assumed population prevalence rate of food allergy.ResultsWe included data from 13 studies describing 240 fatal food anaphylaxis episodes over an estimated 165 million food-allergic person-years. Study quality was mixed, and there was high heterogeneity between study results, possibly due to variation in food allergy prevalence and data collection methods. In food-allergic people, fatal food anaphylaxis has an incidence rate of 1.81 per million person-years (95%CI 0.94, 3.45; range 0.63, 6.68). In sensitivity analysis with different estimated food allergy prevalence, the incidence varied from 1.35 to 2.71 per million person-years. At age 0–19, the incidence rate is 3.25 (1.73, 6.10; range 0.94, 15.75; sensitivity analysis 1.18–6.13). The incidence of fatal food anaphylaxis in food-allergic people is lower than accidental death in the general European population.ConclusionFatal food anaphylaxis for a food-allergic person is rarer than accidental death in the general population.

Risky business? Whether a more accurate picture of risk assessment in food allergic children and young people affects behaviours in school nurses and school first aiders

Background The risk of fatal anaphylaxis in a food allergic person is very low, yet the possibility of this catastrophic event is a major focus for both patients and healthcare professionals. It is unclear how healthcare professionals perceive risk of fatal or non-fatal anaphylaxis in the context of food allergy, and whether their perception of risk influences their management of food allergy. We investigated whether school nurses/first aiders could accurately estimate fatal anaphylaxis risk in children/young people with food allergy, and whether their assessment of risk correlated with their knowledge and management of food allergy in children/young people. Methods Interview-based surveys completed in 30 schools over 6 months included assessment of risk perception in relation to childhood food allergy using a novel risk assessment tool, an assessment of their knowledge of when to administer adrenaline and assessment of their practical ability to use an adrenaline autoinjector. Results Risk perception varied widely but all participants overestimated fatal food anaphylaxis risk more than they overestimated all-cause mortality risk in young people [median log-fold overestimate for all-cause mortality 0.51 (IQR 0.00, 1.48); food anaphylaxis death 1.20 (IQR 0.06, 2.10) p=0.018]. We did not find any association between estimation of anaphylaxis/fatal anaphylaxis risk in a food allergic child, and practical ability to use an adrenaline autoinjector in a simulated scenario. We did however find that participants who state that they would (unnecessarily) dial emergency services for a non-anaphylactic reaction, also significantly overestimated risk of anaphylaxis in a food allergic person (median log-fold overestimate 1.76 (IQR 0.92, 2.33) vs. 0.72 (IQR -1.51, 1.59) for those who would not dial emergency services for a non-anaphylactic reaction (p=0.009). Multivariate analyses showed weak evidence that personal or previous medical experience of allergic disease correlates with increased overestimation of fatal food anaphylaxis risk. Conclusion School nurses/first aiders overestimate fatal food anaphylaxis risk more than overestimating other fatality risks in children. The data suggests that this overestimation of risk is not associated with improved ability to recognise/manage anaphylaxis. These data suggest that correcting any risk misperception among healthcare providers, in relation to risk of anaphylaxis in food allergy, is unlikely to be harmful.

When should self-injectible epinephrine be prescribed for food allergy and when should it be used?

To explore why epinephrine autoinjectors have failed to prevent fatal food anaphylaxis and how this problem might be solved. Autoinjectors cannot save lives when they are used too late, misused, not carried, or when an inadequate dose is absorbed; food allergy-induced asthma may not respond when asthma management is suboptimal. New markers for severe reactions have been published. The fallibility of autoinjectors means that in the management of food allergy, their provision must take second place to accurate identification of the trigger foods, optimal avoidance, and optimal treatment of other medical conditions that make reactions more dangerous.

Deadly combination: Risk-taking behavior, social isolation put teens at high risk for fatal food anaphylaxis

Recent case series of fatalities due to food-induced anaphylaxis indicate that more than 50% of deaths occur in the adolescent age group. Reactions to peanut, tree nuts, seafood and, increasingly, cow's milk account for these deaths. ![Figure][1] Dr. Sicherer The victims typically have

Risk-taking and Coping Strategies of Food Allergic Adolescents and Young Adults

RATIONALE: To identify factors to explain why adolescents and young adults are at high risk for fatal food anaphylaxis. METHODS: Web-based questionnaire based upon focus groups. RESULTS: Participants (174 subjects; 49% male) were 13-21 yrs of age (mean, 16 yrs) and reported: peanut allergy (75%), milk allergy (20%), >2 food allergies (75%), anaphylaxis (82%) and >3 lifetime reactions (52%). Regarding risk-taking, 74% report always carrying epinephrine, but frequencies varied during certain activities: traveling (94%), restaurants (81%), friends' homes (67%), school dance (61%), wearing tight clothes (53%) and sports (43%). While 75% “always” read labels, 42% would eat a food labeled “may contain” an allergen. We designated 29 participants as “High Risk” (HR) because they do not always carry epinephrine and ate foods that “may contain” allergens. The HR group, compared to the rest of the group (p<.05), was less concerned with their allergy, less likely to consider “may contain” labels a risk, had more recent reactions, and felt “different” because of their allergy. The HR group was not distinguishable (p=ns) by age, gender, number of lifetime reactions, or severity of symptoms. Teens variably (60%) tell their friends about their allergy and 68% feel education of their friends would make living with food allergy easier. CONCLUSIONS: A sizeable number of food-allergic teens admit to risk-taking that varies by social circumstances and perceived risks. The results imply that educations of teens, and importantly those around them during social activities, may reduce risk-taking and its consequences.

151 Fatal and near-fatal food anaphylaxis reactions in children

151 Fatal and near-fatal food anaphylaxis reactions in children