Google unveils a glimpse of allergic rhinitis in the real world

Google Trends (GT) is a Web‐based surveillance tool used to explore the searching trends of specific queries on Google. Recent studies have suggested the utility of GT in predicting outbreaks of influenza and other diseases. However, this utility has not been thoroughly evaluated for allergic diseases. Therefore, we investigated the utility of GT for predicting the epidemiology of allergic rhinitis. In the USA, GT for allergic rhinitis showed repetitive seasonality that peaked in late April and early May and then rapidly decreased, and a second small peak occurred in September. These trends are highly correlated with the searching trends for other queries such as ‘pollen count’, antihistamines such as loratadine and cetirizine (all r > 0.88 and all P < 0.001), and even the total pollen count collected from 21 pollen counters across the USA (r = 0.928, P < 0.001). Google Trends for allergic rhinitis was similar to the monthly changes in rhinitis symptoms according to the US National Health and Nutrition Examination Survey III, sales for Claritin^® and all over‐the‐counter antihistamines, and the number of monthly page views of ‘claritin.com’. In conclusion, GT closely reflects the real‐world epidemiology of allergic rhinitis in the USA and could potentially be used as a monitoring tool for allergic rhinitis.     

Validation of an environmental exposure unit for controlled human inhalation studies with grass pollen in patients with seasonal allergic rhinitis

BACKGROUND: There is an increasing need for allergen inhalation systems to perform basic clinical research and test anti-allergic drugs under well-controlled conditions. This requires stability of environmental conditions like temperature and humidity, as well as allergen concentration and reproducible induction of allergic symptoms. OBJECTIVE: The aim of this study was to validate an environmental exposure unit for controlled human pollen inhalation studies in participants with seasonal allergic rhinitis. METHODS: Temperature, relative humidity, and air flow rate were kept constant with an air conditioning system. Pollen atmosphere was generated using a specially designed feeding system and monitored online by laser counter and offline using rotating rod samplers. Efficacy (total nasal symptom score, nasal air flow rate, nasal secretion) and safety (lung function) parameters were evaluated at different pollen concentrations and repeated allergen challenges. RESULTS: Temperature, humidity, and air flow rate in the environmental exposure unit remained constant within a range of <2%. The spatial distribution and the temporal stability of the pollen concentration varied only slightly over 4 h (+/-10% and <4%, respectively). Dose-dependent induction of allergic rhinitis symptoms, reduction in nasal air flow rate, and increase in nasal secretion were observed over time. These effects were reproducible from day to day. Lung function remained clinically normal at all concentrations and from day to day. CONCLUSIONS: Thus, pollen exposure in the environmental exposure unit is an effective, reproducible, safe, and suitable method for single-centre clinical studies on the efficacy of anti-allergic treatment or basic clinical research.     

Prevalence of allergic rhinitis in 3–6-year-old children in Wuhan of China

Background Only a few prevalence studies of allergic rhinitis (AR) have been reported in China. This study aimed to evaluate the prevalence of AR in a population of 3–6-year-old children in Wuhan, China.
Methods Sixteen kindergartens in Wuhan City were randomly selected; for each kindergarten, there were three classes from three grades (top, middle and bottom grade, 3–6 years old, respectively). Questionnaires generated by the authors were distributed and filled out by parents of the selected children, with a telephone interview subsequently. Skin prick test (SPT) was carried out on the children after a written consent was signed by the parents.
Results A total of 1211 (89.5%) valid questionnaires were returned for evaluation. The adjusted current prevalence of AR in 3–6-year-old children was 10.8% with the diagnostic criterion of nasal symptoms(+) and SPTs(+). In the SPTs(+) children, the most common inhalant allergen was house dust mites (94.7%), followed by moulds (28.4%). The prevalence of AR was higher in males than that in females (13.0% vs. 7.7%, P <0.05). 15.8% and 23.2% of AR children were sensitive to egg and milk, respectively. The percentage of children sensitive to both inhalant and food allergens was 27.4%.
Conclusions We found an unexpectedly high prevalence of diagnosed AR in 3–6-year-old children within the investigated population. Dust mite was the most important allergen source for 3–6-year-old children in Wuhan.     

Comparison of olfactory function in patients with seasonal and perennial allergic rhinitis

Hyposmia is a common symptom in allergic rhinitis. However, little is known about differences in the olfactory function of patients with seasonal or perennial allergy. A prospective controlled study was performed on 28 patients with allergic rhinitis to grass pollen and on 47 patients with allergic rhinitis to mites. Sixty-six healthy volunteers served as a control. Olfactory function was evaluated by a modified Connecticut Chemosensory Clinical Research Center testing procedure for threshold, identification, and discrimination. The grass pollen-allergic patients were tested prcseasonally and after 3 weeks of intraseasonal grass pollen exposure: the mite-allergic patients and the volunteers were tested once. In the mite allergies, olfactory threshold, identification, and discrimination tests were significantly worse than in the volunteers (all P<0.0001). In the grass pollen allergies, the results in olfactory identification and discrimination tests were not different from the controls if tested out of the season (both F>0.05). However, in threshold testing (P=0.0139), the results were worse. Intraseasonally, the grass pollen allergies showed a significant decrease in threshold, identification (both P<0.001), and discrimination testing (P=0.0()29). If the intraseasonal pollen allergies were compared to the mite allergies, they showed better results in identification (F=0.(X)87) and threshold (F<0.001) tests, but worse results m discrimination testing (P=0.(XM)2). Therefore, the different kind of allergen exposure seems to result in a different pattern of allergic olfactory dysfunction.     

Serum interleukin-17 levels are related to clinical severity in allergic rhinitis

Background:  T helper (Th)-17 cells are a subset of T helper lymphocytes that exert regulatory activities. Recently, it has been reported that serum interleukin (IL)-17 levels are high in the most severe cases of birch allergy studied outside the pollen season.
Objective:  The aim of this study was to investigate a possible relationship between serum IL-17 levels and clinical parameters in patients with allergic rhinitis studied during the pollen season.
Methods:  In all, 56 patients with persistent pollen-induced allergic rhinitis were evaluated during the pollen season. Serum IL-17 levels were evaluated by enzyme-linked immunosorbent assay. Symptoms were assessed by visual analogue scale, drug use was monitored and peripheral eosinophils were counted.
Results:  Serum IL-17 levels were significantly related to clinical symptoms, drug use and peripheral eosinophil counts ( P  = 0.0001 for all).
Conclusion:  This study provides evidence that serum IL-17 level assessment might be considered to classify allergy severity.     

Up-regulation of IL-18 in allergic rhinitis

BACKGROUND: This paper reports a study on the concentrations of the pro-inflammatory cytokines IL-18 and IL-1beta in nasal secretions of allergic rhinitis patients in relation to ECP and nasal symptoms. METHODS: We measured IL-18 and IL-1beta concentrations using ELISA, and eosinophilic cationic protein (ECP) using the CAP system, in nasal secretions of 15 seasonal allergic rhinitis (SAR) patients at six visits throughout the pollen season. Pollen exposure, nasal and ocular symptoms were monitored daily. Furthermore, we measured IL-18, IL-1beta and ECP concentrations in nasal secretions of 19 controls and 20 symptomatic persistent allergic rhinitis (PAR) patients with house dust mite allergy. RESULTS: In SAR, the increase of IL-18, IL-1beta and ECP paralleled the pollen flight with a time delay. IL-18 and IL-1beta significantly increased during the pollen season compared to baseline, and differently from ECP, remained elevated until 4 weeks after the season. In PAR, the concentrations of IL-18 and ECP, but not IL-1beta, were significantly higher compared to controls, with IL-18 concentrations also being significantly higher than in SAR. CONCLUSION: This is the first study to demonstrate the up-regulation of IL-18 in nasal secretions in allergic rhinitis. The persistence of elevated IL-18 concentrations until after the season and the high concentrations in PAR compared to SAR suggests its role in persistent allergic inflammation.     

Prevalence and features of allergic rhinitis in Italy

BACKGROUND: Italian data on the prevalence of allergic rhinitis are sparse and with wide variations, maybe because of different diagnostic criteria and methods of investigation. This study analyzes the information on rhinitis collected in northern Italy through standardized methods within the European Community Respiratory Health Survey. METHODS: A screening questionnaire was sent by mail to a random sample of the general population aged 20-44 years, and nonresponders were contacted again by phone, achieving a final response rate of 86% (6031/7000). Among the responders, 914 randomly selected underwent a standardized clinical interview, skin prick test (SPT) and total and specific immunoglobulin (Ig)E determination. RESULTS: The overall prevalence of self-reported allergic rhinitis was 15.9% (95% CI 15.0-16.8%). Allergic rhinitis was more common in men below 35 years and in women older than that (P = 0.006), in urban areas (P < 0.001) and in early responders (P < 0.001). A larger percentage of subjects (37.7%) reported nasal symptoms when exposed to indoor or outdoor allergens. Atopy was present in 79% of the subjects reporting allergic rhinitis. CONCLUSIONS: This study demonstrates that the prevalence of allergic rhinitis in northern Italy is similar to the prevalence observed in other European countries and that this disease is more common in urban areas.     

Allergy screening in asthma and allergic rhinitis

To detect atopy by a screening method employing skin prick testing with a limited number of allergens, the test results of 939 patients with allergic airways diseases were analysed. It was found that an allergen panel consisting of cat, timothy and house dust mite could detect 85% of atopic patients with asthma and/or rhinitis. For subgroups of patients the results were even more favourable. Thus 98% of atopic patients with seasonal allergic rhinitis were detected by an allergen panel consisting of timothy, birch and mugwort. It is concluded that screening methods using only three of four allergens could be used for detecting atopy in patients with airways diseases. The method should be most valuable for in vitro tests used in combination with standardized questionnaires.     

Differences between allergic and nonallergic rhinitis in a large sample of adolescents and adults

BACKGROUND: The aim of this study was to describe differences between allergic rhinitis (AR) and nonallergic rhinitis (NAR) in a large community-based sample of Danish adolescents and adults. METHODS: A total of 1,186 subjects, 14-44 years of age, who in a screening questionnaire had reported a history of airway symptoms suggestive of asthma and/or allergy, or who were taking any medication for these conditions were clinically examined. All participants were interviewed about respiratory symptoms and furthermore skin test reactivity, lung function and airway responsiveness were measured using standard techniques. RESULTS: A total of 77% of the subjects with rhinitis had AR, whereas 23% had NAR. Subjects with NAR were more likely to be females, OR = 2.05 (1.31-3.20), P = 0.002, to have persistent symptoms within the last 4 weeks, OR = 1.88 (1.23-2.89), P = 0.003, and to have recurring headaches, OR = 1.94, (1.12-3.37), P = 0.019. On the other hand, subjects with NAR were less likely to have airway hyperresponsiveness, OR = 0.40, (0.24-0.66), P < 0.001, food allergy, OR = 0.40, (0.19-0.36), P = 0.009 and to have been treated with antihistamines in the last 4 weeks, OR = 0.22, (0.13-0.38), P < 0.001 compared with subjects with AR. Subjects with AR were symptomatically worse within their season in terms of sneezing (P < 0.001) and itchy eyes (P < 0.001), compared to subjects with NAR, whereas nasal congestion and rhinorrhea were equally frequent in the two groups (P = 0.901 and P = 0.278, respectively). CONCLUSIONS: The proportion of subjects with NAR in an adolescent and adult population with rhinitis is around one-fourth. Women have NAR twice as often as men. In general, subjects with NAR have more persistent but equally severe symptoms compared to subjects with AR. However, subjects with AR have more sneezing and itchy eyes within their particular season of allergy compared to subjects with NAR.