Background: The genetic factors contributing to exacerbations in type 2–low asthma are not well understood. Objective: We sought to clarify the association between variants in gasdermin B/orosomucoid-like 3 (GSDMB/ORMDL3) on 17q21 and exacerbations in type 2–low asthma. Methods: This follow-up study of the multicenter Kinki Hokuriku Airway disease Conference (KiHAC) enrolled adults with asthma who were receiving inhaled corticosteroids. It examined associations between asthma exacerbations requiring systemic corticosteroids over 2 years and clinical and genetic factors in patients with the type 2–low endo-genotype, defined by serum periostin levels lower than 95 ng/mL and the IL4RA rs8832 A allele. Exacerbation risks were also evaluated in patients with the type 2–low genotype, defined by both the POSTN rs3829365 C allele and the IL4RA rs8832 A allele, using the KiHAC and replication cohorts. The genetic variant rs7216389 in GSDMB was the primary focus for assessing genetic risk. Results: A total of 115 patients with the type 2–low endo-genotype were analyzed (mean age, 62 years; 76.5% female). During the 2-year follow-up, 32 patients experienced 1 or more exacerbation. Multivariate analysis identified the rs7216389 TT genotype, recent exacerbations, female sex, and higher body mass index as independent risk factors for asthma exacerbations in patients with the type 2–low endo-genotype. The association between the rs7216389 TT genotype and exacerbations was confirmed in patients with the type 2–low genotype in the KiHAC (n = 89) and replication (n = 125) cohorts. Conclusions: The rs7216389 TT variant on 17q21 may be an independent risk factor for exacerbations in adults with type 2–low asthma, highlighting the role of GSDMB in its pathophysiology.

BACKGROUND:Periostin, a matricellular protein that modulates cell functions having various pathophysiological roles, has the potential to be a useful biomarker for various diseases. We recently found that periostin forms a complex with IgA in human serum, which may affect the periostin measurement.METHODS:We investigated (1) whether the formation of the periostin-IgA complex affects the original periostin ELISA system, decreasing the values of serum periostin? (2) bow each domain of periostin affects periostin measurement by the original periostin ELISA system? (3) whether we can establish a novel ELISA system that is not affected by formation of the IgA complex?RESULTS:The periostin value at the reducing condition was significantly higher than that of the non-reducing condition, demonstrating that formation of the IgA complex affects periostin measurement. The monoclonal antibodies (mAbs) for periostin recognizing the EMI and R1 domains immunoprecipitated serum periostin in the reducing condition more than in the non-reducing condition, whereas the mAbs recognizing the R2 or R3 domain immunoprecipitated comparable amounts of serum periostin in the reducing and non-reducing conditions, suggesting the EMI and R1 domains contribute to formation of the complex with IgA. Using SS16A recognizing the R3 domain combined with SS17B recognizing the R4 domain, we established an ELISA system that was able to measure periostin independently of the IgA complex.CONCLUSIONS:We have established a novel ELISA system that measures periostin independently of the IgA complex. This system is promising in identifying periostin as a biomarker for various diseases.

Long-term voice abuse or sudden vocal fold microvascular disruption may lead to injury and subsequent repair/remodeling in the vocal fold mucosa. Periostin is known to be involved in airway remodeling and also in various otolaryngological diseases. The aim of this article was to investigate the expression and the role of periostin in the formation of vocal fold polyps. The expression patterns of periostin in 59 surgical specimens of vocal fold polyps from 54 patients were investigated immunohistochemically. Normal vocal fold mucosa specimens from 5 patients who had undergone total laryngectomy were used as the control group. Retrospective study with planned data collection was conducted at Tohoku Medical and Pharmaceutical University. Expression of periostin was detected in 43 (72.9%) samples and four patterns of periostin expression were observed in vocal fold polyps: negative type, superficial type, infiltrative type, and diffuse type. An association was observed between periostin expression patterns and the histological subtypes of vocal fold polyps. The infiltrative pattern of periostin expression was significantly dominant in vascular-hyaline types. Expression of transforming growth factor-β (TGF-β) was also detected in the vocal fold polyps. Our results confirmed that periostin might be involved in certain pathological changes in vocal fold polyps, such as extracellular matrix accumulation, local fibrosis, and formation and development of vocal fold polyps.

BACKGROUND:The chitinase-like protein YKL-40 is associated with airflow limitation on spirometry and airway remodeling in patients with asthma. It remains unclear whether YKL-40 is associated with morphologic changes in the airways and parenchyma or with future progression of airflow limitation in severe asthma. OBJECTIVE:To evaluate the association of circulating YKL-40 levels with morphologic changes in the airways and parenchyma and with longitudinal progression of airflow limitation. METHODS:The patients were participants in the Hokkaido Severe Asthma Cohort Study (n = 127), including smokers. This study consisted of 2 parts. In analysis 1, we analyzed associations between circulating YKL-40 levels and several asthma-related indices, including computed tomography-derived indices of proximal wall area percentage, the complexity of the airways (airway fractal dimension), and the parenchyma (exponent D) cross-sectionally (n = 97). In analysis 2, we evaluated the impact of circulating YKL-40 levels on forced expiratory volume in 1 second (FEV1) decline longitudinally for a 5-year follow-up (n = 103). RESULTS:Circulating YKL-40 levels were significantly associated with proximal wall area percentage and airway fractal dimension (r = 0.25, P = .01; r = -0.22, P = .04, respectively), but not with exponent D. The mean annual change in FEV1 was -33.7 (± 23.3) mL/y, and the circulating YKL-40 level was a significant independent factor associated with annual FEV1 decline (β = -0.24, P = .02), even after controlling for exponent D (β = -0.26, P = .01). CONCLUSION:These results provide further evidence for the association of YKL-40 with the pathogenesis of airway remodeling in severe asthma.

Background: The concept of progressive fibrosing interstitial lung diseases (PF-ILD) has been recently proposed to describe a progressive phenotype in fibrosing ILDs, separate from the classical differential diagnosis of ILDs. However, we still do not know enough about how we can differentiate PF-ILD patients from non–PF-ILD patients in advance or how we can predict decline of lung function in PF-ILD patients. Periostin is a matricellular protein playing a critical role in the pathogenesis of pulmonary fibrosis significantly high in idiopathic pulmonary fibrosis patients. Methods: In this study, we applied three periostin ELISA systems—an original ELISA system recognizing total periostin, an ELISA system recognizing only the monomeric periostin, and a modified ELISA system that can measure periostin independently of the IgA complex established in this study—to serum from idiopathic interstitial pneumonia (IIP) patients to address whether periostin can differentiate PF-ILD from non–PF-ILD patients in advance, whether periostin can predict the decline of lung function in PF-ILD patients, and which ELISA system for periostin is the most suitable for these purposes. Results: We established the modified ELISA system using SS16A recognizing the R3 domain instead of SS18A recognizing the R1 domain as the primary mAb that can measure periostin independently of the IgA complex. All periostin values found by the three systems were significantly higher in PF-ILD patients than in healthy subjects in addition to SP-D and KL-6, whereas all the periostin values, but not SP-D or KL-6, could differentiate PF-ILD patients from patients with IIP other than PF-ILD, in the order of the monomer system, the modified system, and the original system. Moreover, the periostin values by all three systems, but not SP-D or KL-6, showed significant correlations with decline of either %VC or D L, CO , in order of the monomer system, the modified system, and the original system. Conclusions: Serum periostin, but not SP-D and KL-6, differentiates PF-ILD from non–PF-ILD and predicts decline of lung function in PF-ILD patients. The monomer periostin ELISA system is the best at doing so. These results demonstrate that periostin, particularly the monomeric form, is useful in treating PF-ILD patients.

Purpose: To elucidate the usefulness of Japanese cedar pollen (JCP)-specific antigen-specific immunoglobulin (IgG) 4 as a biomarker for predicting the efficacy of sublingual immunotherapy for cedar pollen-induced allergic rhinitis. Methods: We divided a total of 105 cases with Japanese cedar pollinosis into three groups: “SLIT Successful,” SLIT Unsatisfactory,” and “SCIT” groups. The SLIT group patients were treated with JCP Droplet (Torii Pharmaceutical Co. Ltd., Tokyo, Japan) for one year from 2015 and were divided into two groups, the SLIT Successful group or the SLIT Unsatisfactory group. The SLIT Successful group (n = 16) were subjects treated by SLIT only, who were able to experience control of their naso-ocular symptoms without the need for antiallergic rescue agents during the peak season of atmospheric pollen. The SLIT Unsatisfactory group (n = 76) comprised subjects treated with SLIT only, who did not respond successfully, and were administered with rescue agents to control their naso-ocular symptoms. The SCIT group had been treated with standardized JCP extract (Torii Pharmaceutical Co., Ltd., Tokyo, Japan) for three years from 2012, and were also able to experience control of their symptoms during the peak pollen season without the need for antiallergic rescue agents. We determined the serum level of JCP-specific immunoglobulin E (IgE), IgG, and IgG4 used in the 3gAllergy-specific IgE assay (3gAllergy). The serum levels of periostin and SCCA2 were measured using established ELISA procedures (clones SS18A and SS17B; Shino-Test, Japan) following the manufacturer’s instructions. We then made ROC curves for each group and assessed which index was best able to predict the efficacy of sublingual immunotherapy. Results: Serum JCP-specific IgE was significantly lower in the SCIT group than in the SLIT Successful group and the SLIT Unsatisfactory group (p < 0.05). Serum JCP-specific IgG was significantly higher in the SCIT group and the SLIT Successful group than in the SLIT Unsatisfactory group (p < 0.05). Serum JCP-specific IgG4 was also significantly higher in the SCIT group and the SLIT Successful group than in the SLIT Unsatisfactory group (p < 0.05). There was no significant difference among serum levels of periostin in the SCIT group, the SLIT Successful group, or the SLIT Unsatisfactory group. There was also no significant difference in SCCA2 among the three groups. In terms of ROC curves, a serum JCP-specific IgG4 value greater than 989.5 UA/mL showed the best sensitivity (93.3%) and specificity (94.7%) (p < 0.05) among other parameters. Conclusions: The serum JCP-specific IgG4 level is significantly correlated with the clinical efficacy of SLIT. Serum JCP-specific IgG4 cutoff levels greater than 989.5 UA/mL were correlated with an effective clinical response to SLIT, with a sensitivity of 93.3% and a specificity of 94.7%.

Background Asthma is a significant comorbidity of eosinophilic chronic rhinosinusitis (CRS). Type2-driven biomarkers such as sinus tissue eosinophilia and fractional nitric oxide (FeNO) may be utilized to detect high risk patients who develop asthma symptoms after endoscopic sinus surgery (ESS) in CRS patients. Methods Thirty-six CRS patients without asthma who agreed to undergo ESS between October 2015 and December 2017 were prospectively observed for 12 months following ESS. They were monitored for the development of typical asthma symptoms including dyspnea, wheezes, and cough which responded to anti-asthma medication. Biomarkers were compared between patients who developed asthma symptoms after ESS (asthma symptoms group) and those who did not (non-asthma group). Biomarker changes following ESS intervention were also evaluated. Results Six patients were lost to follow after ESS. Thus, 30 CRS patients [16 with nasal polyps (NPs) proved by surgery] were followed. Seven (23%) newly complained of asthma symptoms during follow-up. Levels of FeNO and the prevalence of eosinophilic NPs (eosinophils >= 70/high power fields) were significantly higher in the asthma symptom group than in non-asthma group [50.7 ppb vs 22.4 ppb for FeNO levels, and 100% (n = 3) vs 23% (n = 3) for eosinophilic NP prevalence, both p < 0.05]. Levels of sputum periostin decreased significantly by ESS in the non-asthma group. However, changes of biomarkers after ESS were comparable between the two groups. Conclusions Eosinophils in NPs (>= 70/high power fields) and preoperative FeNO may be significant biomarkers for predicting the development of asthma symptoms after ESS.

Background and Aims: Corticosteroids are mainstay of treatment for patients with asthma.There are subset of patients with severe asthma who have persistent symptoms despite high dose corticosteroid treatment.There is evidence to suggest that type 2 innate lymphoid cells (ILC2s) are involved in the severe asthma with steroid-resistance.Precise mechanisms of steroid resistance induction on ILC2s has not been elucidated.The aim of this study is to address the role of DR3 (death receptor 3), expressed on ILC2s and its ligand, TL1A (tumor necrosis factor-like protein 1A), in the mechanism of steroid resistance induction.Methods: Enriched blood ILC2s, from mild asthmatics were stimulated with IL-2 (10 ng/mL) in combination with either TL1A (10 ng/mL)or TSLP (0.1 ng/mL), then treated with dexamethasone (10À9 M), to assess the steroid responsiveness of the TL1A/DR3 axis.Harvested cells were subject to immunofluorescence staining and enumerated by flow cytometry.Results and Conclusions: Dexamethasone significantly reduced IL-5 production by ILC2s in the IL-2 + TL1A (16.4 AE 4.6 vs. 4.4 AE 1.8%) or IL-2 + TSLP (27.7 AE 7.9 vs. 15.2AE 5.7%) conditions.In contrast, no significant inhibitory effect was noted when TL1A and TSLP were added together.In conclusion the TL1A/DR3 axis in the presence of TSLP induces steroid resistance of ILC2.

Background The associations of serum monomeric periostin (M-PN) level and serial change in M-PN with acute exacerbation of chronic fibrosing interstitial pneumonia (AE-FIP) are unclear. Methods We prospectively measured serum M-PN level from onset of AE to day 14 in 37 patients with AE-FIP and evaluated its association with outcome. To determine localization of periostin expression, immunohistochemical staining of pathological lung tissue from autopsy cases of AE-IPF was evaluated. Results Data from 37 AE-FIP patients (28 men; age 73.9±7.8 years) were analyzed. With healthy controls as reference, serum M-PN level was significantly higher in patients with AE-FIP (P=0.02) but not in those with stable idiopathic pulmonary fibrosis (P=1.00). M-PN was significantly lower on day 7 than at AE-FIP onset in survivors [14.6±5.8 vs. 9.3±2.8 ng/mL (onset to day 7: P<0.001)] but not in non-survivors [14.6±5.1 vs. 13.2±5.1 ng/mL (onset to day 7: P=0.07)]. In analysis using a cut-off value for serial change in M-PN (ΔM-PN), 3-month survival was 92.3% in the ΔM-PN decrease group and 36% in the ΔM-PN increase group (P=0.002). In multivariate analysis, 3-month survival tended to be associated with high ΔM-PN (OR: 12.4, 95% CI: 0.82–187.9, P=0.069). Conclusions Serial change in serum M-PN level may be a prognostic indicator of AE-FIP.

BACKGROUND:We recently reported that squamous cell carcinoma antigen 2 (SCCA2) is a reliable biomarker for atopic dermatitis (AD).OBJECTIVE:To further clarify its utility, we investigated for effects of comorbid allergies and AD treatment on serum SCCA levels.METHODS:Volunteers <18 years old were recruited through our website. Their allergic status was elucidated using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. We also recruited pediatric patients who were hospitalized because of severe AD. The serum levels of SCCA1 and SCCA2 were measured by enzyme-linked immunosorbent assays. In the severe AD patients, the levels of thymus and activation-regulated chemokine (TARC), SCCA1, and SCCA2 were measured before and after hospitalization. The severity of AD was assessed using the severity scoring of atopic dermatitis (SCORAD).RESULTS:A total of 576 participants (547 volunteers and 29 patients) were enrolled in the study. The levels of SCCA1 and SCCA2 were significantly higher in volunteers with mild AD and patients with severe AD than in healthy volunteers without allergic diseases. The levels were not elevated in those who had mild bronchial asthma or allergic rhinitis without AD. TARC, SCCA1, and SCCA2 were decreased during the treatment in severe AD patients, reflecting clinical improvement in response to treatment. Linear regression analysis for predicting a decrease in the SCORAD index showed R2 values of 0.16, 0.38, and 0.48 for TARC, SCCA1, and SCCA2, respectively.CONCLUSION:SCCAs, especially SCCA2, are sensitive biomarkers for detecting AD in children and adolescents and for assessing the severity and response to treatment of severe AD.

Background Bronchopulmonary dysplasia (BPD) is the most common morbidity complicating preterm birth and affects long-term respiratory outcomes. The objectives of this study were to establish whether serum periostin at birth, day of life (DOL) 28, and corrected 36 weeks’ gestational age could be potential biomarkers for BPD. Methods A total of 98 preterm Japanese infants born at <32 weeks and comparing 41 healthy controls born at term, were divided into BPD ( n = 44) and non-BPD ( n = 54) cohorts. Serum periostin levels were measured using an enzyme-linked immunosorbent assay. Results Among 98 preterm infants, the median serum periostin levels at birth were higher with BPD (338.0 ng/mL) than without (275.0 ng/mL, P < 0.001). Multivariate analysis revealed that serum periostin levels at birth were significantly associated with BPD ( P = 0.013). Serum periostin levels at birth with moderate/severe BPD (345.0 ng/mL) were significantly higher than those with non-BPD/mild BPD (283.0 ng/mL, P = 0.006). Conclusions Serum periostin levels were significantly correlated with birth weight and gestational age, and serum periostin levels at birth in BPD infants were significantly higher than that in non-BPD infants. Impact This study found higher serum periostin levels at birth in preterm infants subsequently diagnosed with bronchopulmonary dysplasia. It also emerged that serum periostin levels at birth significantly correlated with gestational age and birth weight. The mechanism by which serum periostin is upregulated in BPD infants needs further investigation.

Background: In all chronic airway diseases, the dynamics of airway function are influenced by underlying airway inflammation and bronchial hyperresponsiveness along with limitations in reversibility owing to airway and lung remodeling as well as mucous plugging. The relative contribution of each component translates into specific clinical patterns of symptoms, quality of life, exacerbation risk, and treatment success. Objective: We aimed to evaluate whether subgrouping of patients with obstructive airway diseases according to patterns of fluctuation in lung function allows identification of specific phenotypes with distinct clinical characteristics. Methods: We applied the novel method of fluctuation-based clustering (FBC) to twice-daily FEV1 measurements recorded over a 1-year period in a mixed group of 134 adults with mild to-moderate asthma, severe asthma, or chronic obstructive pulmonary disease from the European BIOAIR cohort. Results: Independently of clinical diagnosis, FBC divided patients into 4 fluctuation-based clusters with progressively increasing alterations in lung function that corresponded to patterns of increasing clinical severity, risk of exacerbation, and lower quality of life. Clusters of patients with airway disease with significantly elevated levels of biomarkers relating to remodeling (osteonectin) and cellular senescence (plasminogen activator inhibitor-1), accompanied by a loss of airway reversibility, pulmonary hyperinflation, and loss of diffusion capacity, were identified. The 4 clusters generated were stable over time and revealed no differences in levels of markers of type 2 inflammation (blood eosinophils and periostin). Conclusion: FBC-based phenotyping provides another level of information that is complementary to clinical diagnosis and unrelated to eosinophilic inflammation, which could identify patients who may benefit from specific treatment strategies or closer monitoring.

Periostin is known to be a useful biomarker for various diseases. In this article, we focus on allergic diseases and pulmonary fibrosis, for which we and others are now developing detection systems for periostin as a biomarker. Biomarker-based precision medicine in the management of type 2 inflammation and fibrotic diseases since heterogeneity is of utmost importance. Periostin expression is induced by type 2 cytokines (interleukin-4/-13) or transforming growth factor-β, and plays a vital role in the pathogenesis of allergic inflammation or interstitial lung disease, respectively, andits serum levels are correlated disease severity, prognosis and responsiveness to the treatment. We first summarise the importance of type 2 biomarker and then describe the pathological role of periostin in the development and progression of type 2 allergic inflammation and pulmonary fibrosis. In addition, then, we summarise the recent development of assay methods for periostin detection, and analyse the diseases in which periostin concentration is elevated in serum and local biological fluids and its usefulness as a biomarker. Furthermore, we describe recent findings of periostin as a biomarker in the use of biologics or anti-fibrotic therapy. Finally, we describe the factors that influence the change in periostin concentration under the healthy conditions.

Abstract Background Periostin is a matricellular protein and is a useful marker in respiratory diseases. However, the roles of periostin in patients with obstructive sleep apnea (OSA) remain unclear. Several in vitro studies have suggested that mechanical stress, hypoxia, impaired metabolism, and kidney injury, which often accompany OSA, may upregulate the expression of periostin. Meanwhile, serum periostin level has been negatively associated with body mass index (BMI) in the general population. In this study, we hypothesized that a high level of serum periostin despite being overweight/obese may discriminate severe OSA or OSA with comorbidities from mild OSA with obesity alone. We aimed to clarify the roles of periostin in patients with OSA to assist in elucidating the heterogeneity of OSA with comorbidities. Methods Among patients diagnosed as OSA, we examined the associations between serum periostin levels and clinical indices, including the severity of OSA, BMI, and comorbidities, using a multifaceted approach. The serum periostin levels and clinical indices were assessed after 3 months of continuous positive airway pressure (CPAP) treatment. Results In 96 patients with OSA, serum periostin level was negatively correlated with BMI, albeit marginally, and tended to be higher in severe OSA than in others when adjusted for BMI. Cluster analysis identified four clusters, including two severe OSA clusters, one of which was characterized by high serum periostin levels and the presence of comorbidities, including albuminuria. In a comparative analysis of severe OSA cases (n = 53), the level of serum-free fatty acids and the frequency of albuminuria were higher in patients with high serum periostin level of ≥87 ng/mL, which was the highest quintile among all participants, than in those with low serum periostin levels (< 87 ng/mL, n = 41). In patients with severe OSA and high serum periostin levels, the levels of serum periostin and urinary albumin significantly decreased after 3 months of CPAP treatment. Conclusions Elevated serum periostin in patients with OSA despite being overweight/obese may be an indicator of severe OSA with comorbidities, particularly albuminuria.

Background Serum periostin associates with type-2 inflammation in asthmatic airways, but also reflects whole body periostin levels originating from multiple sources. Less is known about sputum periostin as a biomarker in asthma as detection levels are low using currently available periostin assays. We aimed to investigate detection of sputum periostin using ELISA assays targeting different periostin epitopes and relate levels to clinical characteristics. Methods Two ELISA systems were developed using antibodies detecting whole periostin or cleavage products, the molecular weight and amino acid sequences of which were confirmed. The ELISA assays were applied to sputum from 80 patients with mild-to-moderate and severe asthma enrolled in the European, multi-center study BIOAIR. Results were related to clinical characteristics. Results Sputum was found to contain smaller periostin fragments, possibly due to proteolytic cleavage at a C-terminal site. Comparing ELISA methodology using antibodies against cleaved versus whole periostin revealed detectable levels in 90% versus 44% of sputum samples respectively. Sputum periostin showed associations with blood and sputum eosinophils. Furthermore, sputum, but not serum, periostin correlated with reduced lung function and sputum IL-13 and was reduced by oral corticosteroid treatment. Conclusions We present an ELISA method for improved analysis of sputum periostin by detecting cleavage products of the periostin protein. Using this assay, sputum periostin was detectable and associated with more disease-relevant parameters in asthma than serum periostin. Sputum periostin is worth considering as a phenotype-specific biomarker in asthma as its proximity to the airways may eliminate some of the confounding factors known to affect serum periostin.

Background: Type 2 chronic rhinosinusitis (CRS), especially eosinophilic CRS (ECRS), is an intractable upper airway inflammatory disease. Establishment of serum biomarkers reflecting the pathophysiology of CRS is desirable in a clinical setting. As IgG4 production is regulated by type 2 cytokines, we sought to determine whether serum IgG4 levels can be used as a biomarker for CRS. Methods: Association between the serum IgG4 levels and clinicopathological factors was analyzed in 336 CRS patients. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of serum IgG4 levels that can be used to predict the post-operative recurrence. Results: Serum IgG4 levels were significantly higher in patients with moderate to severe ECRS versus those with non to mild ECRS. The levels were also significantly higher in asthmatic patients and patients exhibiting recurrence after surgery compared to controls. ROC analysis determined that the best cut-off value for the serum IgG4 level to predict the post-operative recurrence was 95 mg/dL. The corresponding sensitivity and specificity were 39.7% and 80.5%, respectively. When we combined the two cut-off values for the serum IgG4 and periostin, patients with high serum levels of either IgG4 or periostin exhibited a high post-operative recurrence (OR: 3.95) as compared to patients having low serum levels of both IgG4 and periostin. Conclusions: The present results demonstrate that the serum IgG4 level is associated with disease severity and post-operative course in CRS. In particular, the combination of serum IgG4 and periostin could be a novel biomarker that predicts post-operative recurrence. Copyright (C) 2019, Japanese Society of Allergology. Production and hosting by Elsevier B.V.

Introduction The lack of effective, consistent, reproducible and efficient asthma ascertainment methods results in inconsistent asthma cohorts and study results for clinical trials or other studies. We aimed to assess whether application of expert artificial intelligence (AI)-based natural language processing (NLP) algorithms for two existing asthma criteria to electronic health records of a paediatric population systematically identifies childhood asthma and its subgroups with distinctive characteristics. Methods Using the 1997-2007 Olmsted County Birth Cohort, we applied validated NLP algorithms for Predetermined Asthma Criteria (NLP-PAC) as well as Asthma Predictive Index (NLP-API). We categorised subjects into four groups (both criteria positive (NLP-PAC(+)/NLP-API(+)); PAC positive only (NLP-PAC(+) only); API positive only (NLP-API(+) only); and both criteria negative (NLP-PAC(-)/NLP-API(-))) and characterised them. Results were replicated in unsupervised cluster analysis for asthmatics and a random sample of 300 children using laboratory and pulmonary function tests (PFTs). Results Of the 8196 subjects (51% male, 80% white), we identified 1614 (20%), NLP-PAC(+)/NLP-API(+); 954 (12%), NLP-PAC(+) only; 105 (1%), NLP-API(+) only; and 5523 (67%), NLP-PAC(-)/NLP-API(-). Asthmatic children classified as NLP-PAC(+)/NLP-API(+) showed earlier onset asthma, more Th2-high profile, poorer lung function, higher asthma exacerbation and higher risk of asthma-associated comorbidities compared with other groups. These results were consistent with those based on unsupervised cluster analysis and lab and PFT data of a random sample of study subjects. Conclusion Expert AI-based NLP algorithms for two asthma criteria systematically identify childhood asthma with distinctive characteristics. This approach may improve precision, reproducibility, consistency and efficiency of large-scale clinical studies for asthma and enable population management.

Background: Eosinophilic nasal polyps (NPs) are associated with the presence of asthma in chronic rhinosinusitis (CRS) patients. Serum periostin has been considered a relevant biomarker for unified airway diseases. Objective: To determine the utility of biomarkers including serum periostin that reflects reduction of exacerbations of comorbid asthma in CRS patients. Methods: We prospectively recruited 56 CRS patients who were subjected to undergo endoscopic sinus surgery (ESS) (20 with asthma) between October 2015 and December 2017 and followed them for 1 year after ESS. Blood eosinophil count, serum periostin, and fractional nitric oxide (FeNO) were measured at enrollment. How these type 2-driven biomarkers reflect comorbid asthma was determined using receiver operating characteristic (ROC) analysis. The frequency of asthma exacerbations during 1 year was counted both before and after ESS. Associations between preoperative biomarkers including eosinophils in NPs and asthma exacerbations were evaluated. Results: Blood eosinophil count, FeNO, and serum periostin levels were significantly higher in CRS patients with asthma than in those without (p < 0.01 for all) and discriminated comorbid asthma among CRS patients (p < 0.05; AUC > 0.80 for all). The increased preoperative serum periostin correlated with lower absolute number of postoperative exacerbations (ρ = −0.49, p = 0.03) and its relative reduction after ESS (ρ = 0.53, p = 0.03) in asthmatic patients. Increased eosinophils in NPs were also associated with reduced asthma exacerbations. Conclusion: Preoperative increased serum periostin and eosinophils in NPs are associated with the preventive effect of ESS for asthma exacerbations in CRS patients comorbid with asthma.