Pollen challenge study of a phototherapy device for reducing the symptoms of hay fever.

OBJECTIVE: The objective was to investigate the effect of intranasal phototherapy delivered by a phototherapy device (allergy reliever SN-206) on symptoms of hay fever (seasonal rhinitis) due to grass pollen in adults. This registered class IIA medical device had been on sale for 15 months with no adverse effects reported but there had been no assessment of efficacy. Previous research had indicated that phototherapy could alleviate symptoms of allergic rhinitis but no double-blind, placebo-controlled trails had been done. RESEARCH DESIGN AND METHODS: The trial is a double-blind, placebo-controlled grass pollen challenge conducted out of the pollen season, on 101 adult male and female hay fever sufferers. Subjects were assigned to placebo or active groups by stratified random sampling using responses to a baseline questionnaire. All subjects used active or placebo devices three times a day for 14 days before pollen challenge. Subjects were monitored for 2.5 h after challenge. MAIN OUTCOME MEASURES: Primary outcome measures were observed severity scores for sneezing, running eyes, running nose, and the amount of eosinophil cationic proteins (ECP) in nasal secretions. Secondary outcome measures were symptom scores by subject report (itching eyes, itching nose, itching throat, itching mouth/palate), and nasal peak inspiratory flow (PIFn) and peak expiratory flow (PEFn). RESULTS: Significant reductions in severity of symptom scores were found for sneezing, running nose, running eyes and itchy mouth/palate (p < or = 0.05). No significant differences were found in the results for itchy eyes, itchy nose, itchy throat, ECPs, PIFn and PEFn. No adverse events occurred. CONCLUSIONS: The results show that the device significantly reduced some hay fever symptoms. The study would have been improved if compliance was monitored electronically and if nasal congestion was monitored by report. The mode of action is unclear. The study does not consider long-term implications of the therapy.

A double blind, placebo-controlled cross over trial of cellulose powder by nasal provocation with Der p1 and Der f1.

OBJECTIVE: The purpose of this study was to assess whether inert cellulose powder would reduce the response to nasal challenge with house dust mite antigens. The study aimed to investigate the efficacy of inert cellulose powder applied to the nose for the control of persistent allergic rhinitis in adults due to house dust mite allergy. The powder has been registered as a medical device since 1994 and is available in many countries as a remedy for hay fever. Anecdotal evidence reported that it reduced symptoms of persistent rhinitis but no scientific evidence exists for this. RESEARCH DESIGN AND METHODS: A double blind, placebo-controlled cross over trial was conducted on 15 adult persistent rhinitis sufferers (diagnosed positive to Der p1 and/or Der f1 by SPT) and who had symptoms over the previous 2 years. The placebo was lactose powder. Challenge was by measured dose of homogenised allergenic dust. The study took place in the spring of 2006 before the main pollen seasons. MAIN OUTCOME MEASURES: The primary outcome measures were observed severity scores for 3 symptom categories and the amount of ECP in nasal secretions. The secondary outcome measures were symptom scores by subject report (nasal blockage, itching of nose, throat and eyes), nasal peak inspiratory (PIFn) and expiratory flow (PEFn). RESULTS: The results show significant differences for sneezing, itchy nose, runny nose and ECPs in nasal secretions. Some results are also significantly different between placebo and active for PIFn and for PEFn (all at p = 0.05). There were no adverse reactions. CONCLUSIONS: The inert cellulose powder can have significant effects in reducing some symptoms of persistent rhinitis due to house dust mite allergy.

A double blind, placebo controlled trial of inert cellulose powder for the relief of symptoms of hay fever in adults.

OBJECTIVE: An inert cellulose powder has been on sale in the UK since 1994 as a remedy for hay fever but no scientific trials have been conducted previously. It is applied to the inside of the nose where it forms a gelatinous coating. The principal aim was to determine if there is a significant difference in the amount and type of rescue medication required for adult hay fever sufferers to control their symptoms while using either the inert cellulose powder or a placebo. The second objective was to see whether the cellulose powder resulted in an improvement in symptom control. RESEARCH DESIGN: A double blind, placebo controlled study was conducted of 97 adult hay fever sufferers, over the grass pollen season of 2004. Participants (selectively recruited to be living within the catchment area of a 50-km radius from Worcester, UK) were assigned randomly to two groups (A, Active and B, Placebo) matched by age by decades and gender. Of those completing the trial, group A had 19 males and 28 females and group B had 21 males and 29 females. There were no significant differences between the groups in age distributions, severity of symptoms over the last 2 years or in medication taken. They completed daily symptom diary score cards and were allowed to take any medications they wished in addition to the inert cellulose powder or placebo because medication use was taken as an outcome measure. Results were analysed in relation to pollen counts. RESULTS: Significant differences were found in the amounts of rescue medication taken by the active and placebo groups (p < 0.05). More people in the placebo group took rescue treatments than those in the active group. No significant differences were found (p < 0.01) between the active and placebo groups in Likert scores for any of the rhinitis nasal symptoms or in the total Likert symptom daily scores. No adverse events were reported during the study. CONCLUSIONS: The amount of rescue medication taken by the placebo group was significantly more than that taken by the active group both overall, considering all types of medication, and also in the individual cases of antihistamines, nasal sprays and eye drops. These results provide evidence that the inert cellulose powder reduces the need to take rescue medication for the symptoms of hay fever.

Pollen counts in relation to the prevalence of allergic rhinoconjunctivitis, asthma and atopic eczema in the International Study of Asthma and Allergies in Childhood (ISAAC).

BACKGROUND: Although pollens are major allergens associated with allergic rhinoconjunctivitis and asthma, there is little information about the relative prevalence of these conditions in populations with different pollen exposures. OBJECTIVE: The purpose of this study was to investigate the relationship between pollen exposure and allergic symptoms among children in different countries. METHODS: An ecological analysis was conducted to see whether pollen exposure (pollen counts, and duration and severity of pollen seasons) is associated with symptoms of allergic rhinoconjunctivitis, asthma and atopic eczema in 28 centres within 11 countries (nine being in Europe). Data on the prevalence of symptoms in 13-14-year olds were based on the responses to the written questionnaires from the International Study of Asthma and Allergies in Childhood (ISAAC). The analysis was adjusted for gross national product and mean annual relative humidity. RESULTS: There was little relationship between pollen exposure and symptom prevalence, except for a significant inverse association between grass pollen counts and lifetime prevalence of the symptoms of allergic rhinitis (P=0.03). Almost all the regression coefficients were negative. The associations were even weaker and all non-significant when the analyses were conducted within countries, using a random intercept fixed slope model, but there was still no evidence of a positive association between pollen exposure and symptoms. CONCLUSION: There is a weak but consistent tendency for the prevalence of allergic symptoms to be inversely associated with pollen exposure. This finding accords with evidence from several countries, suggesting that the prevalence of hayfever and asthma tends to be lower in rural than in urban areas, and lowest among people living on farms. Exposure to allergenic pollen in early life does not appear to increase the risk of acquiring symptoms of respiratory allergy, and may even give some protection against them.