35 Body Mass Index (BMI) and Immediate (“STAT”) Dose of Epinephrine im (EPI IM) Needed to Treat Subcutaneous Allergen Immunotherapy (SCIT) Systemic Reactions (SRS)

BACKGROUND: The purposes of this study are to document the number of SRs to SCIT, the relationship between BMI versus the severity of SRs [World Allergy Organization (WAO) Grade 1 to 5 reactions], and the possible relationship between BMI and the total amount of epi IM needed to treat the SRs. METHODS: This is a retrospective study of SRs to optimal dose SCIT with any combination of approximately 20 allergens (pollens, animal emanations, molds, and Hymenoptera) in 840 subjects representing 13,812 encounters over 12 months (June 2010–May 2011). Nurses administered stat epi IM (1:1000 v/v), 0.2 mg, immediately into the arm or thigh for any systemic signs or symptoms (SS) of a SR, including, but not limited to, itchy eyes, nose, pharynx, palms; rhinorrhea, nasal congestion, sneezing; and generalized erythema, pruritus, or urticaria. Repeat doses of epi IM were administered as necessary. RESULTS: 32 subjects (3.8%) each had one SR: 21 (66%) Grade 1, 10 (31%) Grade 2, 1 (3%) Grade 3, and Grades 4 or 5. BMIs were missing in 3 subjects. Fifteen of 29 were in the normal weight range (BMI 18.5–24.9), 9 Grade 1 (mean epi IM, 0.27 mg) and 6 Grade 2 (mean epi IM, 0.3 mg). Mean epi IM was 0.28 mg. Eight of 29 subjects were overweight (BMI 25–29.9), 7 Grade 1 (mean epi IM, 0.23 mg), and 1 Grade 3 (mean epi IM, 0.3 mg). Mean epi IM was 0.24 mg. Six of 29 were obese (BMI >30), 4 Grade 1 (mean epi IM, 0.3 mg) and 2 Grade 2 (mean epi IM, 0.2 mg). Mean epi IM was 0.27 mg. CONCLUSIONS: SRs occurred in 3.8% of SCIT subjects. No significant association was found between BMI and the WAO Grade severity (P = 0.13 by Fisher's exact test) and BMI and total epi IM dose given (P = 0.82 by Kruskal-Wallis test). BMI should not influence risk assessment of SCIT or IM epi administered for SR.