Staphylococcus aureus Enterotoxin-Specific IgE Sensitization in Severe Eosinophilic Asthma Phenotype

Chung Kian Fan 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.2

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Physician-prescribed Asthma Treatment Regimen does not differ Between Smoking and Non-smoking Patients With Asthma in Seoul and Gyunggi province of Korea

박해심,정기석,Kian Fan Chung,Felicia Allen-Ramey,Ryan Pollard,Richard Perry,David Price 대한천식알레르기학회 2015 Allergy, Asthma & Immunology Research Vol.7 No.1

Purpose: Smoking has detrimental effects on asthma symptom control and response to treatment and is prevalent among asthma patients in South Korea. The aim of this study is to determine the prevalence of smoking among asthma patients in South Korea and to compare the medication regimens of asthma patients who do and do not smoke. Methods: A cross-sectional survey was conducted from August 2010 to January 2011. Participating physicians (N=25) recorded demographic and clinical data on all asthma patients presenting during the study period (N=2,032), and then recruited a subset of patients (N=500) for the survey such that half were self-reported current smokers. Recruited patients were between the ages of 18 and 60. Results: Among presenting asthma patients, 17.3% were current smokers, 19.2% were former smokers, and 63.5% had never smoked. Within the analyzable study population (N=471), 212 patients reported smoking currently, 79 smoking formerly, and 180 never smoking. Among current and former smokers, 79.7% and 81.0%, respectively, were men, while women represented 80.5% of patients who had never smoked. Agreement was strong between physician-determined smoking status and patient-reported smoking status (κ=0.82; P<0.001). However, asthma medication regimens examined according to GINA treatment steps did not differ by smoking status. In addition, mean quality of life scores and level of asthma control did not differ by smoking status. Conclusions: In South Korea, physicians are well aware of the smoking status of their patients. However, smoking status did not affect the prescribed medication regimens of this population of asthma patients.

Future Risks in Patients With Severe Asthma

송우정,이지향,강예원,정우정,Kian Fan Chung 대한천식알레르기학회 2019 Allergy, Asthma & Immunology Research Vol.11 No.6

A major burden of severe asthma is the future risk of adverse health outcomes. Patients with severe asthma are prone to serious exacerbation and deterioration of lung function and may experience side effects of medications such as oral corticosteroids (OCSs). However, such future risk is not easily measurable in daily clinical practice. In particular, currently available tools to measure asthma control and asthma-related quality of life incompletely predict the future risk of medication-related morbidity. This is a significant issue in asthma management. This review summarizes the current evidence of future risk in patients with severe asthma. As future risk is poorly perceived by controlled asthmatics, our review focuses on the risk in patients with ‘controlled’ severe asthma. Of note, it is likely that long-term OCS therapy may not prevent future asthma progression, including lung function decline. In addition, the risk of drug side effects increases even during low-dose OCS therapy. Thus, novel treatments are highly desirable for reducing future risks without any loss of asthma control.

Age and Sex Distribution of Chinese Chronic Cough Patients and Their Relationship With Capsaicin Cough Sensitivity

Kefang Lai,Li Long,Fang Yi,Jiaman Tang,Zhe Chen,Fagui Chen,Jianmeng Zhou,Wen Peng,Liting Zhang,Hu Li,Wenzhi Zhan,Ruchong Chen,Wei Luo,Qiaoli Chen,Kian Fan Chung,Nanshan Zhong 대한천식알레르기학회 2019 Allergy, Asthma & Immunology Research Vol.11 No.6

Purpose: An older female predominance has been reported among chronic cough patients in Western countries, which is considered to be associated with a higher cough sensitivity in females. However, the characteristics of Chinese chronic cough patients remain unclear. This study aimed to explore the age and sex distribution as well as their relationship with cough reflex sensitivity to capsaicin in Chinese chronic cough patients. Methods: We analyzed the demographic features of 1,882 consecutive chronic cough patients who attended our cough clinic in Guangzhou, China. Cough sensitivity to capsaicin, which was defined as the lowest concentration of capsaicin causing 5 coughs or more (C5), was measured in 539 of the 1,882 patients and 68 healthy volunteers. Results: The mean age of the patients was 43.0 ± 13.7 years and patients aged <50 years accounted for more than two-thirds of the study population. Around 87% of the patients were never-smokers. The proportion of females (51.5%) was almost equal to that of males (48.5%). The pattern of the age and sex distribution was consistently reflected within most common causes of chronic cough, while a female predominance was shown in patients with coughvariant asthma and patients aged ≥50 years. Female patients had higher cough sensitivity to capsaicin than male patients (log C5: 1.58 ± 0.84 vs. 2.04 ± 0.84 μmol/L, P = 0.001), and patients aged ≥50 years had higher cough sensitivity to capsaicin than patients aged <50 years. Conclusions: In China, patients with chronic cough have a roughly equal sex distribution and a middle-aged predominance, irrespective of a higher cough sensitivity to capsaicin in females and older patients.

Genome-Wide Association Study of Korean Asthmatics: A Comparison With UK Asthmatics

Jin An,도아라,Kang Hae Yeon,김우진,이상훈,Lee Ji-Hyang,Song Woo-Jung,Kwon Hyouk-Soo,조유숙,문희범,Hu Sile,Adcock Ian M,Chung Kian Fan,Won Sungho,Kim Tae-Bum 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.4

Purpose Although genome-wide association studies (GWASs) represent the most powerful approach for identifying genes that influence asthma, to date, no studies have established genetic susceptibility to asthma in the Korean population. This study aimed to identify genetic variants associated with adult Korean asthmatics and compare them with the significant single nucleotide polymorphisms (SNPs) of UK asthmatics from the UK Biobank. Methods Patients were defined as having asthma if they were diagnosed by a doctor or taking medications for asthma. Controls were defined as individuals without asthma or chronic obstructive pulmonary disease. We performed quality control, genotype imputation, GWAS, and PrediXcan analyses. In the GWAS, a P value of < 5 × 10−8 was considered significant. We compared significant SNPs between Korean and UK patients with asthma. Results A total of 1,386 asthmatic patients and 5,205 controls were analyzed. The SNP rs1770, located near the human leukocyte antigen (HLA)-DQB1, was the most significant SNP (P = 4.5 × 10−10). In comparison with 24 SNPs in a GWAS of UK asthmatics, six SNPs were significant with the same odds ratio (OR) direction, including signals related to type 2 inflammation (e.g., IL1RL1, TSLP, and GATA3) and mucus plugging (e.g., MUC5AC). HLA-DQA1 showed an opposite OR direction. The HLA-DQB1 gene demonstrated significantly imputed mRNA expression in the lung tissue and whole blood. Conclusions The SNP rs1770 of HLA-DQB1 was the most significant in Korean asthmatics. Similarities and discrepancies were found in the genetic variants between Korean and UK asthmatics. GWAS of Korean asthmatics should be replicated and compared with those of GWAS of other ethnicities. Purpose Although genome-wide association studies (GWASs) represent the most powerful approach for identifying genes that influence asthma, to date, no studies have established genetic susceptibility to asthma in the Korean population. This study aimed to identify genetic variants associated with adult Korean asthmatics and compare them with the significant single nucleotide polymorphisms (SNPs) of UK asthmatics from the UK Biobank. Methods Patients were defined as having asthma if they were diagnosed by a doctor or taking medications for asthma. Controls were defined as individuals without asthma or chronic obstructive pulmonary disease. We performed quality control, genotype imputation, GWAS, and PrediXcan analyses. In the GWAS, a P value of < 5 × 10−8 was considered significant. We compared significant SNPs between Korean and UK patients with asthma. Results A total of 1,386 asthmatic patients and 5,205 controls were analyzed. The SNP rs1770, located near the human leukocyte antigen (HLA)-DQB1, was the most significant SNP (P = 4.5 × 10−10). In comparison with 24 SNPs in a GWAS of UK asthmatics, six SNPs were significant with the same odds ratio (OR) direction, including signals related to type 2 inflammation (e.g., IL1RL1, TSLP, and GATA3) and mucus plugging (e.g., MUC5AC). HLA-DQA1 showed an opposite OR direction. The HLA-DQB1 gene demonstrated significantly imputed mRNA expression in the lung tissue and whole blood. Conclusions The SNP rs1770 of HLA-DQB1 was the most significant in Korean asthmatics. Similarities and discrepancies were found in the genetic variants between Korean and UK asthmatics. GWAS of Korean asthmatics should be replicated and compared with those of GWAS of other ethnicities.

Clinical Characteristics of Post-COVID-19 Persistent Cough in the Omicron Era

Kang Yu Ri,Huh Jin-Young,Oh Ji-Yoon,Lee Ji-Hyang,Lee Daegeun,Kwon Hyouk-Soo,Kim Tae-Bum,Choi Jae Chol,Cho You Sook,Chung Kian Fan,Park So-Young,Song Woo-Jung 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.3

Cough is one of the most common symptoms of acute coronavirus disease 2019, but cough may persist for weeks or months. This study aimed to examine the clinical characteristics of patients with post-coronavirus disease (COVID) persistent cough in the Omicron era. We conducted a pooled analysis comparing 3 different groups: 1) a prospective cohort of post-COVID cough (> 3 weeks; n = 55), 2) a retrospective cohort of post-COVID cough (> 3 weeks; n = 66), and 3) a prospective cohort of non-COVID chronic cough (CC) (> 8 weeks; n = 100). Cough and health status was assessed using patient-reported outcomes (PROs). Outcomes, including PROs and systemic symptoms, were longitudinally evaluated in the prospective post-COVID cough registry participants receiving usual care. A total of 121 patients with post-COVID cough and 100 with non-COVID CC were studied. Baseline cough-specific PRO scores did not significantly differ between post-COVID cough and non-COVID CC groups. There were no significant differences in chest imaging abnormality or lung function between groups. However, the proportions of patients with fractional exhaled nitric oxide (FeNO) ≥ 25 ppb were 44.7% in those with post-COVID cough and 22.7% in those with non-COVID CC, which were significantly different. In longitudinal assessment of the post-COVID registry (n = 43), cough-specific PROs, such as cough severity or Leicester Cough Questionnaire (LCQ) scores, significantly improved between visits 1 and 2 (visit interval: median 35 [interquartile range, IQR: 23–58] days). In the LCQ score, 83.3% of the patients showed improvement (change ≥ +1.3), but 7.1% had worsened (≤ −1.3). The number of systemic symptoms was median 4 (IQR: 2–7) at visit 1 but decreased to median 2 (IQR: 0–4) at visit 2. In summary, post-COVID persistent cough was similar in overall clinical characteristics to CC. Current cough guideline-based approaches may be effective in most patients with post-COVID cough. Measurement of FeNO levels may also be useful for cough management.