Prevalence Of Japanese Cedar Pollinosis Research Articles

Japanese Cedar Pollen Allergens in Japan.

Pollen from members of the Cupressaceae tree family is one of the most important causes of allergic disease in the world. Cryptomeria japonica (Japanese cedar) and Chamaecyparis obtusa (Japanese cypress) are Japan's most common tree species. The pollen dispersal season is mainly from February to May. The major allergens of Japanese cedar and Japanese cypress exhibit high amino acid sequence similarity due to the phylogenetic relationship between the two species. An epidemiological study has shown that the prevalence of Japanese cedar pollinosis is approximately 40%. Younger children (5 to 9 years old) showed a high prevalence of Japanese cedar pollinosis as 30% in 2019, indicating that season pollinosis is getting worse. Pharmacotherapy is the most common treatment for pollinosis induced by Japanese cedar and Japanese cypress. Patients' satisfaction with pharmacotherapy is low due to insufficient experienced effect and daytime somnolence. Unlike pharmacotherapy, allergy immunotherapy (AIT) addresses the basic immunological mechanisms of allergic disease and activates protective allergen-reactive pathways of the immune system. AIT is now recognized as the only treatment option with the potential to provide long-term post-treatment benefits and alter the natural course of the allergic disease, including Japanese cedar pollinosis.

The Relationship between Pollen Count Levels and Prevalence of Japanese Cedar Pollinosis in Northeast Japan

The prevalence of Japanese cedar (JC) pollinosis in Japanese children is increasing. However, few studies have reported the relationship between pollen count levels and the prevalence of pollinosis. To evaluate the relationship between JC pollen count levels and the prevalence of pollinosis in children, we investigated the sensitization and development of symptoms for JC pollen in two areas of Akita in northeast Japan with contrasting levels of exposure to JC pollen. The study population consisted of 339 elementary school students (10-11 years of age) from the coastal and mountainous areas of Akita in 2005-2006. A questionnaire about symptoms of allergic rhinitis was filled out by the students' parents. A blood sample was taken to determine specific IgE antibodies against five common aeroallergens. The mean pollen count in the mountainous areas was two times higher than that in the coastal areas in 1996-2006. The prevalence rates of nasal allergy symptoms and sensitization for mites were almost the same in both areas. On the other hand, the rates of nasal allergy symptoms and sensitization for JC pollen were significantly higher in the mountainous areas than in the coastal areas. The rate of the development of symptoms among children sensitized for JC pollen was almost the same in both areas. These results suggest that pollen count levels may correlate with the rate of sensitization for JC pollinosis, but may not affect the rate of onset among sensitized children in northeast Japan.

Asthma in patients with Japanese cedar pollinosis.

:Japanese cedar pollen is the most common causative allergen for seasonal allergic rhinitis (AR) in Japan. More commonly known as Japanese cedar pollinosis, it occurs in spring causing the typical symptoms of seasonal AR, such as sneezing, rhinorrhea, nasal obstruction, nasal itching, and itching of the eyes. Previous reports indicate that the prevalence of Japanese cedar pollinosis among Japanese was 26.5%. According to a more recent questionnaire-based survey, the prevalence of Japanese cedar pollinosis in patients with adult asthma might be up to 30% to 50%, suggesting higher rates than that previously reported. Moreover, 30% to 60% of adult asthmatic patients with concomitant pollinosis have exacerbations of their asthma symptoms during the Japanese cedar pollen season. These findings suggest that concomitant Japanese cedar pollinosis may be an aggravating factor in patients with asthma. As with other pollens, such as grass and birch, Japanese cedar pollen was shown to be a trigger factor for worsening asthma. In clinical practice, a number of Japanese patients with asthma are monosensitized to Japanese cedar pollen but not to other antigens. Further studies are needed to elucidate the mechanisms of Japanese cedar pollen in inducing and in exacerbating asthma. The presence of concomitant AR is often associated with the difficulty in asthma control. However, there has been a controversy whether treating concomitant AR by intranasal corticosteroid would produce better asthma-related outcomes in patients with asthma and AR. The effect of treating concomitant cedar pollinosis by intranasal corticosteroids on asthma control in patients with asthma and cedar pollinosis also remains unknown. Certain systemic treatments, such as leukotriene receptor antagonist and anti-IgE monoclonal antibody, are supposed to reduce the symptoms of both asthma and AR in patients with asthma and concomitant AR. In conclusion, Japanese cedar pollinosis is often associated with exacerbations of asthma. Further investigations are expected to elucidate the precise impact and mechanisms of Japanese cedar pollinosis in asthma.

Asthma in Patients With Japanese Cedar Pollinosis

Japanese cedar pollen is the most common causative allergen for seasonal allergic rhinitis (AR) in Japan. More commonly known as Japanese cedar pollinosis, it occurs in spring causing the typical symptoms of seasonal AR, such as sneezing, rhinorrhea, nasal obstruction, nasal itching, and itching of the eyes. Previous reports indicate that the prevalence of Japanese cedar pollinosis among Japanese was 26.5%. According to a more recent questionnaire-based survey, the prevalence of Japanese cedar pollinosis in patients with adult asthma might be up to 30% to 50%, suggesting higher rates than that previously reported. Moreover, 30% to 60% of adult asthmatic patients with concomitant pollinosis have exacerbations of their asthma symptoms during the Japanese cedar pollen season. These findings suggest that concomitant Japanese cedar pollinosis may be an aggravating factor in patients with asthma. As with other pollens, such as grass and birch, Japanese cedar pollen was shown to be a trigger factor for worsening asthma. In clinical practice, a number of Japanese patients with asthma are monosensitized to Japanese cedar pollen but not to other antigens. Further studies are needed to elucidate the mechanisms of Japanese cedar pollen in inducing and in exacerbating asthma. The presence of concomitant AR is often associated with the difficulty in asthma control. However, there has been a controversy whether treating concomitant AR by intranasal corticosteroid would produce better asthma-related outcomes in patients with asthma and AR. The effect of treating concomitant cedar pollinosis by intranasal corticosteroids on asthma control in patients with asthma and cedar pollinosis also remains unknown. Certain systemic treatments, such as leukotriene receptor antagonist and anti-IgE monoclonal antibody, are supposed to reduce the symptoms of both asthma and AR in patients with asthma and concomitant AR. In conclusion, Japanese cedar pollinosis is often associated with exacerbations of asthma. Further investigations are expected to elucidate the precise impact and mechanisms of Japanese cedar pollinosis in asthma.

Prevalence of Japanese cedar pollinosis in Tokyo: a survey conducted by the Tokyo Metropolitan Government

SummaryIn 2006, a survey was conducted to estimate the prevalence of Japanese cedar pollinosis in three target areas in Tokyo, namely Akiruno‐shi, Chofu‐shi, and Ota‐ku; this survey was similar to two surveys conducted previously, in 1983–1987 (first survey) and 1996 (second survey). In the most recent survey, the overall prevalence of Japanese cedar pollinosis in Tokyo, except the islands of Tokyo, was estimated as 28.2%. This prevalence rate exceeds that estimated by the first and second surveys by 18.2 and 8.8 percentage points, respectively. The prevalence of Japanese cedar pollinosis in the three survey target areas increased by 2.3–10.8 percentage points vs. the rates obtained in the second survey. Furthermore, differences among the prevalence rates in the three areas decreased. Compared with the results obtained in the second survey, increases in the prevalence rate were noted in all age groups other than in people aged 30–44 years. In particular, the prevalence rate in children aged 0–14 years increased markedly, showing a threefold increase. The prevalence rate exceeded 30% in all age groups between 15 and 59 years.

Update on epidemiology of pollinosis in Japan: changes over the last 10 years

SummaryA nationwide epidemiologic survey of atopic diseases including allergic pollinosis was conducted in 9656 Japanese otorhinolaryngologists and their family members during the Japanese cedar pollen dispersion season in 2008 using methods identical to a previous survey that was performed in 1998. The survey response rate was 37.7% (compared with 42.8% in 1998). The overall prevalence rate of Japanese cedar pollinosis was 26.5%, which is an increase of approximately 9% from that noted in 1998. Similar increases were observed in all age groups, and the prevalence rate was similar between male and female respondents. A unimodal distribution was observed in male and female subjects, with a peak in both men and women aged in their 40s. Nationwide, a consistent positive relation was observed between the prevalence of Japanese cedar pollinosis and the regional Japanese cedar pollen counts. The prevalence rate of pollinosis other than Japanese cedar pollinosis and of perennial allergic rhinitis was 15.4% and 23.3%, respectively; both disease entities tended to occur more frequently in male than in female subjects. The prevalence rate of asthma, atopic dermatitis, and food allergy was 5.2%, 14.1%, and 3.9%, respectively. Our results suggest that the prevalence rates of atopic diseases including Japanese cedar pollinosis are dramatically increasing across all age groups in Japan. In particular, the increasing prevalence rate of Japanese cedar pollinosis seems to reflect higher exposure to the Japanese cedar pollen antigen in many prefectures.

スギ花粉症の疫学‐有病率と感作率について‐

Recently, it was reported that the incidence of Japanese cedar pollinosis has increased in Japan since 1990. In this study, specific IgE antibodies to Japanese cedar pollen were measured by the CAP method. The subjects were 1, 100 patients who visited the Allegergy Clinic of the Department of Otolaryngology, Kawasaki Medical School between 2000 and 2007. The sensitization rate was 62.7%. The percent positivity was highest in the 20-29 years old group, and decreased with age.From these findings, the nationwide prevalence of Japanese cedar pollinosis was estimated to be between 15 and 20%. In addition, the annual numbers of patients with Japanese cedar pollinosis was found to be been increasing. Further epidemiological studies in various regions are required to clarify the regional variation in the prevalence of cedar pollinosis.

Aiming towards effective preventive medicine against Japanese cedar pollinosis: epidemiology, patient investigation and integrated research including genotype analyses

SummaryEnvironmental rather than genetic factors appear to play the major role in the recent increased prevalence of Japanese cedar pollinosis in Japan. However, investigating the genes that determine IgE levels and analysing gene polymorphisms may assist in finding new methods of treatment and establishing preventive medicine against this disease. Among a total of 219 asymptomatic individuals who were anti‐Japanese cedar pollen IgE antibody positive as determined by radioallergosorbent test (RAST), only a handful subsequently developed symptoms of Japanese cedar pollinosis or secondary onset of Japanese cedar pollinosis over 5–14 years of follow‐up. Among those who subsequently developed secondary onset of disease, >50% were found to have high initial RAST scores, suggesting that the incidence of Japanese cedar pollinosis is correlated with RAST score. Hence, it may be prudent to advise asymptomatic individuals with high RAST scores to avoid exposure to Japanese cedar pollen so as to delay onset of the disease. Analysis of sequence variants of the FcɛRIβ gene revealed that patients with nasal allergy exhibit a single‐nucleotide polymorphism in which the amino acid at 237 of the intracellular domain changes from glutamine to glycine more frequently than individuals without nasal allergy. Furthermore, Il homo polymorphism of the IL‐4Rα gene is associated with higher serum nonspecific IgE and Japanese cedar pollen‐specific IgE levels than are seen in individuals showing Il,Val hetero and Val homo expression types. When the age of pollinosis onset was compared among these three genotypes, it was found to be significantly lower among Il homo type than the other two expression types, suggesting that Il homo type individuals seem characteristically pre‐disposed to early onset of pollinosis. Studies comparing eosinophil‐associated gene polymorphism in healthy and pollinosis phenotypes have revealed several relationships among the various genotypes and specific disease parameters and suggest that Eotaxin G (123G/A) and IL5 (–703C/T) genotypes can affect the timing of symptom onset after sensitization as well as nasal mucosal hyper‐responsiveness.

Prevalence of Japanese cedar pollinosis in children aged under 15 years throughout Japan

SummaryThe prevalence of childhood allergic rhinitis is increasing steadily in Japan. Affected children are sensitized mainly by house dust mites; however, the prevalence of Japanese cedar pollinosis (JCP) in children is also on the rise. To ascertain the prevalence and current status of JCP in Japanese children, a retrospective analysis of a nationwide cross‐sectional random sampling study was conducted. The survey, conducted shortly after the peak pollen season, was performed by self‐evaluation questionnaire in 2001. Data from children aged under 15 years were collected and analysed. In these subjects, the response rate was 75.1%. The prevalence of JCP was 10.2% in children. Rhinorrhoea was the severest symptom reported; 19.5% had severe or moderate interference with daily activities and consulted physicians. Few children used prescribed drugs and some took measures to avoid contact with allergens.

The genetics of pollinosis

SummaryJapanese cedar pollinosis is an allergic disease characterized by sneezing and itchy and watery eyes in persons with a specific immunoglobulin (Ig)E antibody to this allergen. Since 1960, the prevalence of Japanese cedar pollinosis has greatly increased in Japan. Both environmental and host factors contribute strongly to the pathogenesis of allergic disorders such as allergic rhinitis. The best‐established risk factor for nasal allergy is family history of allergy, especially nasal allergy. Susceptibility genes are genes in which only a few mutational changes may lead to sensitivity to certain diseases. Japanese cedar or orchard grass pollinosis may be diseases of this type, related to the haplotype of human leukocyte antigen. Recent studies of susceptibility genes of allergic diseases have focused on the IgE receptor gene, which is closely related to the pathogenesis of allergic diseases, interleukin (IL)‐4, IL‐4 receptor and interferon genes, which are concerned with the Th2‐ and Th1‐immune responses. However, these susceptibility genes exhibit different behaviours in different ethnic populations and their contribution to conferring disease is not yet established. In addition, allergic rhinitis, especially pollinosis, may be strongly influenced by environmental factors.

アレルギー性鼻炎治療の将来展望

Allergic rhinitis is a relatively common disorder in the general population. Especially, seasonal allergic rhinitis (Japanese cedar pollinosis) has become a serious social problem between February and April in Japan. The age-adjusted prevalence of Japanese cedar pollinosis in Japan in 2000 was 19.4% by a cross-sectional random sampling method.Antihistamines, leukotriene modifiers and nasal steroids are now popular therapies for allergic rhinitis. Only antigen-specific immunotherapy has been accepted as an etiologic treatment available to patients with nasal allergy. Studies are ongoing to determine the efficacy of less invasive delivery routes for vaccination, including oral and sublingual vaccination. A surgical approach (submucous turbinectomy and neurectomy of posterior nasal nerve) has been demonstrated to be effective treatment for stuffy nose.As new strategies for immunotherapy, peptide therapy, anti-IgE antibody (Omalizumab), a human immunoglobulin Feγ-Fce chimeric protein and an allergen vaccine conjugated with CpG-DNA has have administered to allergic patients in clinical trials. Signal transduction by stimulation in human immunopotential cells has been investigated in terms of for cell-specific response. Ideally, these methods will eventually be replaced by strategies targeting the prevention of allergic responses.

Prevalence of Japanese Cedar Pollinosis among Schoolchildren in Japan

Background: Japanese cedar pollinosis is an important allergic rhinoconjunctivitis in Japan in spring. We investigated the relationship between the amount of pollen in the air and the prevalence of the disease and sensitization to Japanese cedar pollen in this ecological study. Methods: The IgE antibody to Japanese cedar pollen (JCP-IgE) was determined in human serum and rhinoconjunctival symptoms were surveyed in 407–510 children in May or June every year from 1995 to 2001. Japanese cedar pollinosis was defined as being JCP-IgE ≧1.5 IU/ml and having any rhinoconjunctival symptom lasting 3 weeks or longer in March or April. Results: Prevalence rates of Japanese cedar pollinosis were 13.8–22.9%. Prevalence rates of being JCP-IgE ≧1.5 IU/ml were 39.0–50.1%, and those of being JCP-IgE ≧15.01 IU/ml were 11.4–23.2%. All prevalence rates were significantly related to the amount of pollen in the air. The proportion of subjects with rhinoconjunctival symptoms was relatively constant in each stratum of low JCP-IgE levels (<0.35, 1.50–2.99, 3.0–14.9 IU/ml). Conclusion: High exposure to Japanese cedar pollen was associated with higher levels of JCP-IgE antibody and a high prevalence of Japanese cedar pollinosis. The relationship between the level of JCP-IgE and the proportion of subjects with symptoms was relatively constant.

Process and current status of the epidemiologic studies on cedar pollinosis in Japan.

This paper reviews the present situation and future aspects of epidemiologic studies on Japanese cedar pollinosis. Increase of allergic rhinitis patients is observed in both the Patient Survey and the Reports on the Surveys of Social Medical Care Insurance Services, however, these surveys are conducted when cedar pollens do not pollute the air. Many have reported on the prevalence of pollinosis in limited areas but only a few nationwide epidemiologic surveys have been conducted. Most of the studies were conducted at special medical facilities such as university hospitals. There is a high possibility that patients who visit the specific facilities do not exactly represent the actual number of patients and epidemiologic pictures of pollinosis in Japan. The rapid advances in laboratory test methods may change the diagnostic criteria and increase the number of reported patients. Therefore, the prevalence of Japanese cedar pollinosis in Japan has not been determined yet. Determination of the prevalence of cedar pollinosis and description of the epidemiologic pictures constitute the essential steps toward the control of this clinical entity. Thus it is necessary to conduct an epidemiologic survey on Japanese representative samples with a standardized survey form with clear and concise diagnostic criteria.