Asthma Severity Is a Risk Factor for Acute Hypersensitivity Reactions to Contrast Agents

Abstract

CT imaging has become a common diagnostic tool because of its utility. However, adverse events from contrast agents have also increased.1Barrett BJ Contrast nephrotoxicity.J Am Soc Nephrol. 1994; 5: 125-137PubMed Google Scholar Controversy exists as to whether asthma is a risk factor for acute hypersensitivity reactions to contrast agents.2Lang DM Alpern MB Visintainer PF Smith ST Increased risk for anaphylactoid reaction from contrast media in patients on beta-adrenergic blockers or with asthma.Ann Intern Med. 1991; 115: 270-276Crossref PubMed Scopus (126) Google Scholar, 3Bettmann MA Heeren T Greenfield A Goudey C Adverse events with radiographic contrast agents: results of the SCVIR Contrast Agent Registry.Radiology. 1997; 203: 611-620Crossref PubMed Scopus (161) Google Scholar Additional data and evaluations are required to reach definitive conclusions. This study aims to evaluate the risk of hypersensitivity reactions to contrast agents in patients with asthma by the severity of asthma. A retrospective cohort study of all adult patients who underwent contrast-enhanced CT imaging tests with IV contrast agents from 2004 through 2011 was conducted at St. Luke's International Hospital. All parameters that are potentially related to acute hypersensitivity to contrast agents, including asthma history, were collected before testing. The patients with asthma were divided into five groups by severity, according to the GINA (Global Initiative for Asthma) guidelines.4The Global Initiative For Asthma Pocket guide for asthma management and prevention. GINA website.http://www.ginasthma.org/pdf/GINA_Pocket_2010a.pdfGoogle Scholar According to the guideline, patients in step 1 were treated without steroids. Patients in steps 2 through 4 were prescribed inhaled steroids. Patients in step 5 were mostly treated with oral steroids. Acute hypersensitivity reactions to contrast agents were defined according to the anaphylaxis criteria as occurring within 24 h.5Ellis AK Day JH Diagnosis and management of anaphylaxis.CMAJ. 2003; 169: 307-311PubMed Google Scholar This study was approved by Research Ethics Committee of St. Luke's International Hospital (11-R133). According to the result of univariate analyses and clinical importance, variables were included in the logistic regression model. The acute hypersensitivity reactions of patients with asthma in each GINA step were compared with the patients without asthma. Analyses were conducted using SPSS (SPSS Inc) and Stata (Statview). CT imaging with contrast was performed on 36,472 patients. Four hundred eighty of these patients (1.3%, 95% CI: 1.2-1.4) had an acute hypersensitivity reaction. A total of 10 patients (2.1%, 95% CI: 1.0-3.8) had asthma (step 1: eight; step 2: one; step 3: one; step 4: 0; and step 5: 0) in the hypersensitivity reaction group; a total of 266 patients (0.7%, 95% CI: 0.7-0.8) had asthma (step 1: 151; step 2: 25; step 3: 33; step 4: 20; and step 5: 37) in the no-reaction group. In the hypersensitivity reaction group, there were only a few patients in steps 2 to 5; therefore, we combined steps 2 to 5 in logistic regression. As compared with patients who did not have asthma, patients who were treated with GINA step 1 had a high risk (OR 3.28). However, there were no significant differences among patients with steps 2 to 5 asthma (OR 0.98) (Table 1). Patients with GINA step 1 asthma may have a higher risk of hypersensitivity reactions to contrast agents for CT imaging. Further evaluations are needed for patients classified as GINA steps 2 to 5.Table 1The Results From the Multivariable Logistic RegressionOR95% CIP ValueAge, y0.980.98–0.99<.01Male sex1.030.85–0.24.77Total iodine compound amount, g1.011.00–1.02<.01Allergic history to contrast agents6.134.60–8.17<.01Allergic history to any drugs1.731.32–2.27<.01Medical history Asthma…….01 No asthmaReferenceReference GINA step 13.281.50–7.15<.01 GINA steps 2–50.980.22–4.43.98 Urticaria2.521.90–3.34<.01 Atopic dermatitis0.510.22–1.20.12Medication Oral steroid users without asthma0.580.25–1.31.19 Inhaled steroid users without asthma0.910.48–1.73.78 NSAID users0.910.75–1.11.36 β-Blocker users1.250.82–1.92.30 ACE inhibitor users0.690.38–1.26.23 Antihistamine users1.370.96–1.95.08ACE = angiotensin-converting enzyme; GINA = Global Initiative for Asthma; NSAID = nonsteroidal antiinflammatory drug. Open table in a new tab ACE = angiotensin-converting enzyme; GINA = Global Initiative for Asthma; NSAID = nonsteroidal antiinflammatory drug.