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JACI Clinical Highlights – November 2008The following summaries highlight several of the clinically relevant articles featured in the November 2008 issue of The Journal of Allergy and Clinical Immunology (JACI). These articles have been selected by the Editors for their novel findings, outstanding study design, and potential usefulness to practicing clinicians.
Antihistamines During Bee Venom Immunotherapy—What About Safety and Efficacy?
Immunotherapy with bee venom protects most patients with a history of allergic bee sting reactions. However, allergic side effects during dose increase are frequent. Preventive treatment with antihistamines is therefore often prescribed. Because T lymphocytes involved in immunoregulation during immunotherapy bear histamine receptors, antihistamine treatment could influence efficacy of immunotherapy. To analyze this, Müller et al. performed a double-blind, placebo-controlled study on 54 bee venom allergic patients treated with antihistamine, levocetirizine or placebo during dose increase (first three weeks) of immunotherapy. Side effects were significantly more frequent in patients on placebo. Four on placebo dropped out because of repeated allergic reactions. No difference in efficacy was indicated by the reaction to a sting challenge after four months of immunotherapy. Allergen-specific protective IgG-antibodies increased significantly in both groups. Allergen-stimulated T-cells from both groups showed decreased proliferation. The decrease in IFN- and IL-13 on placebo was not prominent on levocetirizine, whereas IL-10 showed a significant increase on levocetirizine only. Decreased T-cell expression of histamine receptor HR1/HR2 ratio on day 21 on placebo was prevented by levocetirizine. In conclusion, levocetirizine during dose increase reduces side effects without influencing efficacy of immunotherapy. It also modulates the natural course of allergen-specific immune response.
“Clinical and Immunologic Effects of H1 Antihistamine Preventive Medication During Honey Bee Venom Immunotherapy” by Müller et al.
(JACI November 2008 Volume 122 No. 5)
Positive Allergy Tests by Themselves Are Inadequate Markers of Allergic Disease
The prevalence of allergic diseases is increasing worldwide, but the reasons are not well understood. Previous studies suggest that this trend might be associated with lifestyle and urbanization. Kim et al. performed skin testing to a variety of foods and aeroallergens on more than 2,000 twins among an agricultural Chinese population, the majority being farmers. Of 2,118 subjects, 58% were male. Ages ranged from 11 to 71 years; 43% were children (or under 18 years of age). Over 47% of participants had at least one positive skin test (also called allergen sensitization). The most common sensitizing foods were shellfish (17%) and peanut (12%). The most common sensitizing environmental allergens were dust mite (31%) and cockroach (25%). The rates of allergic disease, such as food allergy and asthma, were estimated to be less than 1%. Allergen sensitization was far more common than the rate of allergic disease in this rural farming Chinese community. Therefore, evidence of sensitization is an inadequate marker of allergic disease, and better correlates with clinical disease are needed. It remains to be determined if the rate of allergic disease will increase in this rural community with expanding urbanization and lifestyle changes that become more akin to those in westernized countries.
“Dissociation Between the Prevalence of Atopy and Allergic Disease in Rural China Among Children and Adults” by Kim et al.
(JACI November 2008 Volume 122 No. 5)
New Clinical Tool Assesses Asthma Disease Status of Ethnically Diverse Patients During Routine Care
As reported by Patino et al., the Asthma Control and Communication Instrument (ACCI) is a new clinical tool specifically developed to systematically assess distinct domains of asthma disease status relevant to generalists, specialists, and patients when making treatment decisions: Acute Care, Bother, Control, Direction and Adherence to Medications (Patino). The questions were derived from focus groups and modified through cognitive interviews with ethnically diverse patients and clinicians to ensure appropriateness, cultural sensitivity, comprehension and usefulness to ultimately increase provider-patient communication about asthma during clinical care visits. The authors previously reported the importance of ACCI domains in informing treatment decisions by clinicians using self-administered vignettes of follow-up visits for adult and pediatric patients with asthma (Diette, Okelo). They now show strong evidence for construct validity of the ACCI in black and white adult patients in comparison with subjective, objective and clinically relevant measures: self-report of general, respiratory and asthma-specific quality of life and asthma control; pulmonary function; and asthma control rated by specialists. The unique features of the ACCI make it a very promising tool to aid busy clinicians in adjusting treatment according to accurate measures of asthma disease status. The investigators are currently finalizing the analysis of clinical trial results testing the ACCI’s efficacy in improving asthma disease assessment during routine clinical visits with generalists.
“The Asthma Control and Communication Instrument: A Clinical Tool Developed for Ethnically Diverse Populations” by Patino et al.
(JACI November 2008 Volume 122 No. 5)
Subjective Measures of Cough Poorly Represent Cough Rates in Asthma
Studies assessing cough frequently use subjective patient reporting as outcome measures, but ambulatory cough monitors are now permitting the objective quantification of cough frequency. Marsden et al. compared subjective measures of cough, cough reflex sensitivity to citric acid, cough-related quality of life (using the Leicester Cough Questionnaire) and manually counted 24-hour ambulatory cough recordings in 56 subjects with asthma. Overall cough rates were higher than in healthy age-matched controls; moreover, subjects with asthma also coughed more by day than by night. Time spent coughing correlated more closely with quality of life scores than with either subjective estimates of cough or cough reflex sensitivity. Cough rates were unrelated to standard measures of asthma but were influenced by both gender and age, with females and older subjects having a higher cough rate. This is the first study to describe the relationships between objective and subjective measures of cough in patients with classical asthma (i.e., patients not selected for the symptom of cough). It highlights the need for objective cough monitoring in studies assessing interventions for cough in asthma.
“A Comparison of Objective and Subjective Measures of Cough in Asthma” by Marsden et al.
(JACI November 2008 Volume 122 No. 5)
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