Presentation on theme: "1 Allergy and Asthma: Improving Outcomes in Primary Care Len Fromer, M.D., FAAFP AsthmaWRAP—SlideCAST."— Presentation transcript:
1 Allergy and Asthma: Improving Outcomes in Primary Care Len Fromer, M.D., FAAFP AsthmaWRAP—SlideCAST
2 The Etiology Challenge ► Common symptoms and diseases have many possible etiologies ► IgE-mediated allergies trigger symptoms from infancy into adulthood ► Identification of true underlying cause is essential for effective management
4 Common Childhood Diseases ► The illnesses of the Allergy March Atopic dermatitis (eczema) GI distress Recurrent otitis media Allergic rhinitis Allergic asthma ► The symptoms Inflammatory in nature Multiple etiologies Treated empirically
5 The Allergy March: A Progression of Seemingly Unrelated Diseases Atopic Dermatitis GI Distress Recurrent Otitis Media Allergic Asthma Allergic Rhinitis Food Sensitivity Inhalant Sensitivity Time (~years) Genetic Predisposition
6 0 10 20 30 40 50 Age (years) Prevalence of Atopic Disease 1 3510 17 Symptoms GastrointestinalRespiratory Skin Prevalence (%) Saarinen UM, Kajosaari M. Lancet. 1995;346:1065-1069. Allergy March
7 Age (years) 0 1 2 3 IgE Antibody Level 4 - 9 0 - 3 10 - 15 n= 122912 Mean score ( Phadebas RAST Class) Sigurs N, et al. J Allergy Clin Immunol. 1994;94:757-763. Allergy March Birch pollen Peanut Egg white
8 Common Childhood Diseases ► Atopic dermatitis (AD) 1 17%-20% prevalence in US, other western countries Not necessarily severe reaction (anaphylaxis) Driven by early exposure and sensitization 40% of AD caused by food sensitivity Empirical treatment: trials of topicals 1. 1.Leung DYM. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:561-573.
9 Common Childhood Diseases ► GI distress 1 Colic, diarrhea, vomiting, constipation, reflux Multiple etiologies: – atopy, infection, intolerance, malabsorption, inflammatory bowel, anatomic defect 10%-42% of symptomatic patients are atopic 2,3 50%-60% of infants with food sensitivities show GI symptoms (not necessarily full-blown food allergy) – Empirical treatment: trials of formulas 1. 1.Høst A, Halken S. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:488-494. 2. 2.Australasian Society of Clinical Immunology and Allergy. Adverse reactions to food. Available at: http://www.allergy.org.au/aer/infobulletins/adverse_reactions.htm. 3. 3.Sicherer SH. Pediatrics. 2003;111:1609-1616.
10 Common Childhood Diseases ► Recurrent otitis media (OM) 26% prevalence in US 1 Key risk factors include attendance in daycare, cigarette smoke exposure 2 40%-50% involve atopy 3,4 Common underlying cause = eustachian tube dysfunction – Caused by inflammation related to allergy or infection – Recurrence = not treating the underlying cause Empirical treatment: antibiotics, surgery 1. 1.Lanphear BP, et al. Pediatrics. 1997;99:1-7. 2. 2.AAAAI. The Allergy Report. 2000;2:155-161. 3. 3.Data on file, Pharmacia Diagnostics. 4. 4.Fireman P. J Allergy Clin Immunol. 1997;99:S787-S797
11 Atopy’s Long-Term Consequences ► Nearly 80% of children with AD go on to develop allergic rhinitis and/or asthma 1 ► Children with early and long-lasting food sensitization: 3x more likely to develop allergic rhinitis (AR) than those transiently sensitized 2 5x more likely to develop asthma than those transiently sensitized 2 ► Young wheezers with confirmed atopy are more likely to develop asthma 3 1. Leung DYM. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:561-573. 2. Kulig M, et al. Pediatr Allergy Immunol. 1998;9:61-67. 3. Martinez FD, et al. J Allergy Clin Immunol 1999;104:S169-S174.
12 Knowledge of Etiology Guides Treatment for Today and Tomorrow ► Specific IgE testing in children can help the clinician: – Identify allergen sensitivities – Counsel for avoidance – Eliminate or reduce symptoms – Reduce medication use (including antibiotics) ► Targeting atopy can eliminate symptoms and interrupt the Allergy March 1-5 – ETAC: Cetirizine and avoidance halved asthma risk in children with AD 1 – PAT: Immunotherapy significantly reduced asthma risk in children with AR 2 – CCAPPS: Multifaceted avoidance intervention reduced asthma prevalence 56% in high-risk children 5 1. 1.ETAC ® Study Group. Pediatr Allergy Immunol. 1998;9:116-124. 2. 2.Möller C, et al. J Allergy Clin Immunol. 2002;109:251-256. 3. 3.Platts-Mills TAE. N Engl J Med. 2003;349:207-208. 4. 4.Sampson H. Ann Allergy Asthma Immunol. 2004;93:307-308. 5. 5.Chan-Yeung M, et al. J Allergy Clin Immunol. 2005;116:49-55.
17 Comparison of Quality-of-Life in Asthmatic and Chronic Rhinitis Patients
18 Distribution of URD in US 1-3 ► 39% of total population (115M of 295M) have URD 1. 1.AHRQ. Management of allergic and nonallergic rhinitis. May 2002: AHRQ Pub. No. 02-E023. 2. 2.Spector SL, ed. Dialogues in Redefining Rhinitis. 1996;1(1,4):1-16. 3. 3.Allergy Statistics.AAAAI Web site. Available at: http://www.aaaai.org/media/resources/media_kit/allergy_statistics.stm. 40M 35M 40M Sinusitis 30% Non-allergic Rhinitis 35% Allergic Rhinitis 35%
19 Actual Atopy and Antihistamine Use 1. Szeinbach SL, et al. J Manag Care Pharm. 2004;10(3):234-238. Identification of allergic disease among users of antihistamines 1 ► ► Allergic rhinitis, non-allergic rhinitis, sinusitis ► ► Study of managed-care patients repeatedly prescribed oral antihistamines ► ► Convenience sample of 246 evaluated with in vitro allergy testing ► ► Results revealed non-atopic symptom etiology in 2/3 of patients 35% Atopic E tiology 65% Non-atopic E tiology
20 Non-allergic Rhinitis ► Wide array of types and etiologies 1,2etiologies Includes: infectious, vasomotor, hormonal, anatomic, occupational, drug-induced ► Not caused by IgE-mediated allergic inflammation Non-sedating antihistamines and other allergy-targeted therapies will not treat underlying cause 1. 1.AAAAI. The Allergy Report. 2000;2:1-31. 2. 2.Dykewicz MS, et al. Ann Allergy Asthma Immunol. 1998;81:478-518.
21 Allergic Rhinitis ► Triggered by seasonal or perennial allergen(s) ► Symptoms may include : Nasal congestion, rhinorrhea, increased secretions, sneezing, itchy nose/eyes, watery eyes, coughing, postnasal drip 1,2 ► Cumulative threshold disease 3,4 : Patients are rarely monosensitized Symptoms emerge after “allergic threshold” has been exceeded 1. 1.AAAAI. The Allergy Report. 2000;2:1-31. 2. 2.Dykewicz MS, et al. Ann Allergy Asthma Immunol. 1998;81:478-518. 3. 3.Pharmacia & Upjohn Diagnostics. The Value of Allergen Identification.1998. Publication 98006.01. 4. 4.Wickman M. Allergy. 2005;60 (Suppl 79):14-18.
22 Cumulative Threshold Disease 1 1. Pharmacia & Upjohn Diagnostics. The Value of Allergen Identification. 1998. Publication 98006.01. 2. Ciprandi G, et al. J Allergy Clin Immunol. 1995;96:971-979. 3. Boner AL, et al. Clin Exp Allergy. 1993;23:1021-1026. Symptoms Situation A 2 No avoidance measures Situation B 3 No avoidance measures Third allergen Situation C 3 AvoidanceAvoidance measures employed Third allergen Cat dander Dust mites Ragweed
23 Support for Avoidance in the Management of Allergies and Asthma ► …It has become clear that early intervention may modulate the natural course of atopic disease…the reduction in exposure of high-risk infants to food and house-dust mite allergens substantially lowers the frequency of allergic manifestations in infancy.” 1 – Halmerbauer, et al. ► “Extensive experience suggests that both drug treatment and immunotherapy are more effective if patients also decrease exposure. The approach is to identify the allergen source (or sources) to which the patient is allergic and to educate patients extensively.” 2 – Platts-Mills, et al. ► The NIH, AAAAI, and AAFP urge trigger avoidance as a cornerstone of asthma management 3-5 1. Halmerbauer G, et al Pediatr Allergy Immunol. 2003;14:10-17. 2. Platts-Mills TAE, et al. J Allergy Clin Immunol. 2000;106(5)787-804. 3. NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051. 4. AAAAI. The Allergy Report. 2000;2:33-109. 5. AAFP. Asthma & Allergy Resource Guide. 2004:11-13
24 Sinusitis ► Multiple etiologies Caused by inflammation from infection, allergy, structural abnormalities, other causes 1 ENT experts use term “rhinosinusitis” due to epithelial continuum of sinus/nasal passages 1,2 ► Common comorbidity–often with atopy Rarely occurs without concurrent rhinitis 2 >50% of moderate to severe asthmatics have chronic rhinosinusitis 3 1. 1.Brook I, et al. Ann Otol Rhinol Laryngol. 2000;109:2-20. 2. 2.AAO-HNS. Fact sheet. ENT Link Web site. Available at: http://www.entnet.org/healthinfo/sinus/allergic_rhinitis.cfm. 3. 3.AAAAI. The Allergy Report. 2000;2:7,137-153.
25 Why Should You Test? ► History and physical alone yield a correct diagnosis only 50% of the time 1 ► Different etiologies demand different treatment approaches ► Testing for specific IgE levels can rule in/out atopy ► If atopic: – NSAs probably drug of choice – Testing can help clinician pinpoint offending allergens ► If non-atopic: – Results will allow you to focus on other etiologies – Drugs of choice may include decongestants/steroids – Patient can avoid unnecessary/ineffective treatment 1. Homburger HA. Arch Pathol Lab Med. 2004;128:1028-1031.
26 URD Management Options Specific IgE-Positive/Abnormal Atopic Etiology Specific Allergen Avoidance Adequate Response Allergy-Targeted Pharmacotherapy (eg, NSAs, LTRAs) Stop Inadequate Response Referral? Inadequate Response Specific IgE-Negative/Normal Non-Atopic Etiology Adequate Response Pharmacotherapy (allergy-targeted Rx not helpful) Stop Inadequate Response Referral?
27 The Experts on Differential Diagnosis of Rhinitis “A positive diagnosis (or diagnoses) should be made before formulating management.” 1 1. 1.Middleton E, et al, eds. Allergy: Principles & Practice. Vol II, 5th ed. St. Louis, Mo: Mosley-Year Book, Inc; 1998:1007.
28 The Experts on Differential Diagnosis of Rhinitis ► An expert panel in the area of allergy diagnosis recommended selective use of in vitro allergy testing by primary care physicians. ► According to these experts, in vitro tests 1 : Offer a well standardized alternative to skin testing Are easily used by generalist physicians Are effective in the diagnosis of allergy 1. Selner JC, et al. Ann Allergy Asthma Immunol. 1999;82:407-412.
29 The Experts on Differential Diagnosis of Rhinitis “Allergy [IgE] testing should be considered in all patients with a suspected diagnosis of allergic rhinitis.” 1 1. 1.Bierman CW, et al, eds. Allergy, Asthma, and Immunology From Infancy to Adulthood. 3rd ed. Philadelphia, Pa: WB Sanders Company; 1995:403-404.
32 Lower Respiratory Diseases ► Course and severity affected by inflammation (often caused by allergy) ► Underlying atopy shown to increase symptoms and precipitate exacerbations ► A wide range of possible triggers include : Allergy Occupational exposures Infection GERD Tobacco smoke Emotional stress Exercise Cold weather
33 Asthma ► Widespread 7% prevalence (>20 million 1 ) and rising 73% managed by PCPs 2 ► Allergic vs. non-allergic asthma 60% of asthmatics have allergic asthma 3 90% of children with asthma also have allergies 4 1. 1.NCHS. Asthma prevalence, health care use and mortality 2002. Available at: http://www.cdc.gov/nchs/Default.htm. 2. 2.NCHS. Ambulatory care visits 1999–2000. Available at: http://www.cdc.gov/nchs/Default.htm. 3. 3.Milgrom H. Understanding allergic asthma [AAAAI News Release]. June 18, 2003. 4. 4.HØst A, Halken S. Allergy. 2000;55:600-608.
34 The “One Airway” Concept ► Common inflammatory process links upper and lower airways 1 Asthma and allergic rhinitis commonly co-exist 2,3 In concomitant disease, experts recommend evaluation and treatment of one condition to aid management of the other 4 Asthma management guidelines from ARIA, 4 the NIH, 5 AAFP, 6 and AAAAI 7 encourage treatment of AR (and other URDs) to help control asthma 1. 1.Bachert C, et al. Immunol Allergy Clin N Am. 2004;24:19-43. 2. 2.Nayak AS. Allergy Asthma Proc. 2003;24:395-402. 3. 3.Halpern MT, et al. J Asthma. 2004;41:117-126. 4. 4.Bousquet J, et al. Allergic Rhinitis and its Impact on Asthma (ARIA). Allergy. 2002;57:841-855. 5. 5.NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051. 6. 6.AAFP. Asthma & Allergy Resource Guide. 2004:18. 7. 7.AAAAI. The Allergy Report. 2000;2:33,54.
35 NIH Asthma Guidelines 1 Trigger identification/control is primary management step ► “For at least those patients with persistent asthma on daily medications, the clinician should: Identify allergen exposures Use the patient’s history to assess sensitivity to seasonal allergens Use skin testing or in vitro [blood] testing to assess sensitivity to perennial indoor allergens Assess the significance of positive tests in context of the patient’s medical history” 1. 1.NIH. Guidelines for the Diagnosis and Management of Asthma.1997. NIH publication 97-4051.
36 NIH Asthma Guidelines 1 (cont’d) ► “Use skin testing or in vitro testing to determine the presence of specific IgE antibodies to the indoor allergens to which the patient is exposed year round.” ► Allergy testing is the only reliable way to determine sensitivity to perennial indoor allergens.” ► For selected patients with asthma at any level of severity, detection of specific IgE sensitivity to seasonal or perennial allergens may be indicated as a basis for avoidance, or immunotherapy, or to characterize the patient’s atopic status.” 1. 1.NIH. Guidelines for the Diagnosis and Management of Asthma. 1997. NIH publication 97-4051.
37 Knowledge of Symptom Triggers Guides Management ► Allergy testing may be conducted along with pulmonary function tests and other diagnostic evaluations 1 ► In allergic asthma: Confirm atopy and identify specific allergic triggers for avoidance counseling, symptom reduction, and control of severity and comorbid AR ► In non-allergic asthma: Rule out atopy to focus on possible non-allergic triggers Prevent needless control measures 1. 1.NIH. Practical Guide for the Diagnosis and Management of Asthma. 1997. NIH publication 97-4053.
38 Asthma Management Options Specific IgE-Negative/Normal Non-Atopic Etiology Referral? Inadequate Response Adequate Response Pharmacotherapy Allergy Rx not helpful Controller(s) Rescue Rx Stop Focus on Non-allergic Triggers Specific IgE-Positive/Abnormal Atopic Etiology Specific Allergen Avoidance Adequate Response Pharmacotherapy Treat AR (eg, NSAs) LTRAs Controller(s) Rescue Rx Stop Inadequate Response Referral? Inadequate Response
39 What Is Happening to Treatment? ► Mechanism of disease is better understood Means that treatments are nearer the root cause ► Therapeutic specificity is increasing Therapeutic specificity is increasing Diseases are different and differentiation is key The mechanism of action of drugs is more specific than ever Diagnostic precision by PCP is necessary – New diagnostic technology must be employed
40 Market Review: The Role of Diagnostics in Pharmacotherapy Medications for Respiratory Allergy $$$$$$ Highly specific treatment Highly specific resolution of symptoms due to IgE response only — necessitates perfect diagnosis Binds to IgE; Suppression of IgE response Anti-IgE Vaccine (2003) $$$ Very specific to atopy — necessitates even more accurate diagnosis (Doctors report marginal response for AR with Singulair — could be 65% are not allergic) Specific resolution of symptoms of atopy by blocking another mediator pathway Leukotriene antagonist Montelukast (2002) $$ Introduction of “D” formula creates less specific treatment More specific resolution of symptoms primarily due to atopic etiology — necessitates more specific diagnosis Antihistamine effect with very little anticholinergic effect Non-sedating Antihistamines (1990s) $ Broad (shotgun) Non-specific resolution of symptoms regardless of etiology Antihistamine effect + Anticholinergic effect 1st Generation Antihistamines (1970s) Cost Therapeutic Approach Treatment Results Mode(s) of Action Treatment Progression
42 In-vitro Testing: Gain Knowledge to Guide Treatment ► FDA-cleared quantitative measure of specific IgE ► Only a single blood draw required ► Covered under most insurance plans ► Accuracy superior to RAST TM*1 Next-generation assay offers consistently improved sensitivity,2 De facto standard, documented in >2,700 peer-reviewed publications 3 ► In vitro blood testing and skin prick testing (SPT) viewed as interchangeable 4 interchangeable 4 ► In-vitro testing is available throughout the nation from all major reference and clinical laboratories, including Quest Diagnostics, NS-LIJ & BioReference * RAST is a trademark of Pharmacia Diagnostics. 1. 1.Williams PB, et al. J Allergy Clin Immunol. 2000;105:1221-1230. 2. 2.Szeinbach SL, et al. Ann Allergy Asthma Immunol. 2001;86:373-381. 3. Johansson SGO. Expert Rev Mol Diagn. 2004;4:273-279. 4. Hamilton RG. In: Pediatric Allergy: Principles and Practice. Mosby-Year Book, Inc; 2003:233-242.
43 H. Drevin, 1989 A. Kober, 2004 Solid-phase Protein Binding Capacity Comparison Solid Phase cellulose polymer binds almost 150 times more protein than a passively coated tube, well or bead, and about 250 percent more protein than a paper disc.
44 Accuracy of Immunoassays for Specific IgE *The authors noted that regression values below 0.80 reflect poor performance in the ability to correctly detect levels of specific IgE antibodies. ONLY CAP RAST had consistently acceptable regression values. **Alastat was recently replaced by 3gAllergy. Studies show 93% agreement between both methods. Williams PB, et al. J Allergy Clin Immunol. 2000;105:1221-1230. Line represents minimum acceptable R 2 performance values Alastat/ 3gAllergy TM** RAST/ Modified RAST Newest generation: In-vitro testing Ideal Test (Correlation Coefficient).65.82.96 -.98 1.0
45 Predictive Value vs. Skin Prick Testing (SPT)* Performance parametersIn vitro † SPT Sensitivity (%)87.293.8 Specificity (%)90.580.1 PPV (%)91.190.1 NPV (%)86.487.1 Clinical Efficiency (%)88.889.2 *Adapted from Reference 1. † in-vitro Specific IgE blood test was used in this study. 1. Wood RA, et al. J Allergy Clin Immunol. 1999;103:733-779. Authors concluded that In-vitro testing Specific IgE blood test and SPT values both exhibited excellent efficiency 1
46 Profiles Carefully Designed ► Profiles engineered to detect >95% of patients with allergy 1-3 ► Regional respiratory profiles include key indoor/outdoor allergens selected according to: Geographic pollen patterns Regional disease prevalence Cross reactivity to other allergens in each inhalant class ► Allergy March profiles include key food/inhalant allergens Six foods account for 90% of food allergy reactions in children 4 Inhalants include common/cross-reactive indoor and outdoor allergens Generally recommended for children ≤6 years of age, based on symptoms 1. 1.Sampson HA, Ho DG. J Allergy Clin Immunol. 1997;100:444-451. 2. 2.Yunginger JW, et al. J Allergy Clin Immunol. 2000;105:1077-1084. 3. 3.Poon AW, et al. Am J Man Care. 1998;4:969-985. 4. 4.AAAAI. The Allergy Report. 2000;3:69.
47 Understanding Total IgE 1 ► Total IgE often of little practical value when considered aloneconsidered alone ► Levels rarely high when specific IgE titers are not ► Lacks sensitivity as a rule-out screen: Specific IgE levels may be significantly high when total IgE is low/normal ► Extremely high total IgE may be seen in some very rare non-atopic conditions 2 : Certain immunodeficiency diseases (including HIV) IgE myeloma Drug-induced interstitial nephritis Graft-versus-host disease Parasitic diseases Skin diseases in addition to eczema Hyper-IgE syndrome (dermatitis, recurrent pyogenic infection ) 1. 1.Fromer LM. J Fam Pract. 2004;suppl:S4-S14. 2. 2.AAAAI. The Allergy Report. 2000;1:35.
48 Understanding Total IgE *Includes URDs (Upper Respiratory Diseases), CHDs (Childhood Diseases), and LRDs (Lower Respiratory Diseases) 1. AAAAI. The Allergy Report. 2000;1:35.12 Interpretation of Total IgE* Results Negative (Normal) Positive (Abnormal, Elevated) Negative (Normal) Positive (Abnormal, Elevated) Non-allergic Patient Scenario A Rare 1 Scenario B Allergic Patient Scenario C Allergic Patient Scenario D Specific IgE Reading Total IgE Reading
49 Summary ► Diagnostic precision leads to evidence-based medical care Improves patient care Creates better patient satisfaction Provides more appropriate referrals ► In-vitro testing Specific IgE blood test is an accurate test to differentiate atopic from non-atopic patients ► Experts, specialty organizations, and government agencies support allergy testing in primary care
50 URD Inhalant Panel Interpretation Of Results
51 Allergy and Asthma: Improving Outcomes in Primary Care Len Fromer, M.D., FAAFP AsthmaWRAP—SlideCAST