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Putting food allergy in to perspective. Jan Sinclair Paediatric Allergy & Clinical Immunology Starship. The problem. Allergy blamed for death at dinner By Martin Johnston 5:00 AM Thurs Apr 26, 2007
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Putting food allergy in to perspective Jan Sinclair Paediatric Allergy & Clinical Immunology Starship
The problem Allergy blamed for death at dinner By Martin Johnston 5:00 AM Thurs Apr 26, 2007 Grant Freeman sat down to a tomato entree on Tuesday night last week at a work dinner. Ten minutes later he collapsed in the toilet. Two days later he was dead, a suspected victim of a food allergy
Outline • Food allergy risks • Available data • Factors influencing risk • Impact of food allergy • Quality of life • Resilience factors • Questions and discussion
Risks • Aim of management to avoid reactions • Nuisance reactions – unpleasant but not dangerous • Life threatening reactions • Data difficult • Severe reactions not always recognized • Differentiation from asthma • Fatal reactions not always classified as such
Fatal anaphylaxis registers • USA n=31 2001 – 2006 • 19 M, 12 F • Peanut 17, tree nuts 8, milk 4, shrimp 2 • School/college (3 colleges), home/friend (12), restaurants (8), work/office setting (4), and camp (2) • All with known data had asthma • Timely adrenaline 4 • “Many” no previous severe reaction • No previous adrenaline • No previous hospital visit for reaction Bock JACI 07
Fatal anaphylaxis registers • UK n=48 2001 – 2006 • Milk 6, peanut 10, nuts 9, uncertain 18 • fish 1, shellfish 1, snail 1, sesame 1, egg 1, tomato 1 • Home 24 (own 14 other 10), restaurant 11 (4 were abroad), out and about 7 (4 takeout food) • work 1, school 2, nursery 1, camp 2 • 40% Rx EpiPen® • Including 11/13 with previous severe reaction • >50% with relatively mild previous reaction • 10/32 known to have active asthma prior to fatal food allergic reaction Pumphrey JACI 07
Population perspective • UK study of deaths and severe reactions • Retrospective search for fatalities • Prospective survey of fatal and severe reactions • Retrospective fatalities: 8 over 10 years • 0.006 deaths per 100 000 children 0–15 years per yr • Prospective: 48 severe and 6 near fatal over 2 years • 0.19 and 0.02 per 100 000 children 0–15 years per yr • If ~5% of children have food allergy • risk that a food allergic child will die from a food allergic reaction 1 in 800,000 per year • Chance of sudden, unexpected, non violent death • 3:100,000 child per yr Macdougall Arch Dis Ch 2002
Risk factors - cashew • 49 cashew vs. 94 peanut • Likelihood of wheeze 8.4X, cardiovascular symptoms 13.6X, adrenaline 13.3X, severe reaction 25.1X • 213 children with peanut or nut allergy • 74% cashew reaction anaphylactic vs. 30% peanut
Factors not influencing risk Clark Clin Exp All 2003
RAST and risk Patient 1 RAST Type Grade Specific IgE KU(A)/L Nut mix 1 4+ N/A N/A Nut mix 2 4+ N/A N/A Almond 4+ N/A N/A Brazil nut 4+ N/A N/A Cashew nut 4+ N/A N/A Coconut 3+ N/A N/A Hazel nut 4+ N/A N/A Pecan nut 4+ N/A N/A Pistachio 4+ N/A N/A Walnut 4+ N/A N/A Peanut 4+ 30* 15 Nut mix 1: Peanut, Hazelnut, Brazil nut, Almond and Coconut. Nut mix 2: Pecan nut, Cashew nut, Pistachio and Walnut. Patient 2 RAST Type Grade Specific IgE Nut mix 1 0 N/A N/A Nut mix 2 0 N/A N/A Cashew nut 0 N/A N/A Pistachio 0 N/A N/A Peanut 0 <0.35 15 Pine nut 0 Nut mix 1 contains Peanut, Hazelnut, Brazil nut, Almond and Coconut. Nut mix 2 contains Pecan nut, Cashew nut, Pistachio and Walnut.
Factors not influencing risk Clark Clin Exp All 2003
Food allergy psychological burden • Peanut allergy c.f. rheumatologic disease • 153 vs. 69 children, and 37 vs. 42 adults • Peanut allergy associated with more disruption of daily activity and impact on family relations in children • Rheumatologic disease associated with more impact than peanut allergy in adults Primeau, Clin Exp All, 2000
Food allergy quality of life • Quality of life of 20 children with peanut allergy compared with 20 children with IDDM • Self reported lower QoL for children with peanut allergy c.f. IDDM • More fear of an adverse event • Anxiety symptoms particularly when eating away from home • More threatened by perceived hazards within the environment Avery, Ped All Imm 2003
Management and QoL • 41 peanut / nut allergic children and their mothers • Maternal and child QoL and anxiety were not influenced by the severity of previous reactions • Not influenced by sensitised vs allergic • 14 with hospital care, 5 Rx adrenaline • Mother and child reported lower anxiety was prescribed an epinephrine auto-injector (36 of 41 had autoinjector) • Anxiety was not associated with whether the child carried the auto-injector (25 often or always) • Anxiety not associated with whether they strictly avoided “traces” of nuts in foods • 29 who ate “may contain” with better QoL than 11 who didn’t Cummings Ped All Imm 2010
Challenge and QoL • 131 egg allergic, 36 sensitised never exposed • Challenge reduced adverse parental concerns • For 6/10 parameters, expectations concerning egg allergy in children who had been challenged were significantly better than those who had never been challenged irrespective of the challenge outcome. • The greater certainty provided by the performance of a food challenge may be a positive outcome in both CP and CN children Kemp Paed All Imm 09
Education and QoL Vickers 1997
Teens and food allergy • Structured interviews n=21 • 4 themes identified • Way of life/coming to know FHS as a way of life. • Experiencing and coping with burden • Alleviation/exacerbation of the burden of living with FHS • Managing acceptable risk • 9 low risk, high burden • 10 minimising risk, minimising burden • 2 tolerating risk, low burden HIGH MED LOW BURDEN LOW MED HIGH RISK MacKenzie Ped All Imm 2010
Developmental trajectory • Children <8 • Own food is “special” • Confident in parent’s control • Around 8-9 years • “Special” develops negative connotations • Awareness of uncertainty • Older and more independent • Increasing uncertainty • Reinforced by lack of awareness of others • Awareness of anxiety of parents • “Difference” as isolation DunnGalvin Adv Food Nutr Res 2009
Strategy – avoidance – 40% • Specifically allergen related ↔ generalised of places, people, situations • Generalised related to high levels of anxiety and low levels of self efficacy • Not related to severity previous reactions “It is better to not go to restaurants... you never know…the waiters don't know” “I only go to places where I know I am safe” “We wouldn't go to restaurants because they are not safe” “I only go to friends houses who I know for ages...its safer that way” DunnGalvin Allergy 2009
Strategy - minimisation • Minimisation strategies 30% • Rejection of food allergic identity, adopting risky behavior “I just want to be like the other kids…and bringing up about the allergy, that just makes you weird” “Sometimes I forget my pen on purpose; you just got to chance it will be ok…you'd go mad otherwise” “I was sitting in a friends house with a group of guys and they started firing peanuts at me…they didn't know, I don’t tell people but that was a freaky moment” DunnGalvin Allergy 2009
Strategy - adaptive • Positive emotional, cognitive or behavioural strategies used to cope with the everyday experience of living with food allergy • Children whose parents encouraged independence and self-management were more likely to describe positive coping strategies “If there's food around, I will be careful, but otherwise I don't think about it” “I’m lucky cause I don't like cake…well if I tried it, I might like it, but I decided I didn't like it” “I always tell people I'm food allergic…its safer that way and then you don't have to keep explaining DunnGalvin Allergy 2009
Building resilience • Age appropriate strategies • Peanut minimisation in preschools, won’t work by intermediate • Review and adapt with time and developmental progress • Focus on avoiding ingestion • Reactions to touch and inhalation possible but rare • Systemic reactions not reproduced with peanut smell • Education re allergen • Identification • Hidden sources • Following the family rules
Building resilience • Confidence about • Avoidance strategies • Age appropriate • Child needs to be ready for these to change • Managing uncertainty • What won’t hurt • Recognition about • Reaction signs and symptoms • How to get help • Practice with autoinjector (parents older child)