Page 17 - ADULT-ONSET ASTHMA PREDICTORS OF CLINICAL COURSE AND SEVERITY

PURPOSE OF THIS THESIS
This thesis focuses on the clinical course and severity of adult-onset asthma, which is poorly studied and remains poorly understood. So far, a very limited number of longitudinal studies in adult-onset asthma pa ents have been performed. The wide variety of clinical phenotypes and underlying pathophysiological mechanisms described above has been observed mainly in cross-sec onal studies or studies with childhood-onset asthma pa ents. The course of adult-onset asthma over me is s ll largely unknown, although incidence and prevalence of the disease are increasing, with almost half of all asthma pa ents in a secondary clinic having adult-onset disease. This leaves clinicians with uncertain es about the prognosis in a large propor on of their asthma pa ents, whereas in the clinic it is important to recognize pa ents who develop frequent asthma exacerba ons or increased asthma severity in an early phase of the disease to allow intensive treatment and strict monitoring. On the contrary, it can be reassuring and might prevent overtreatment to recognize pa ents who will have asthma remission. Early interven ons targeted to the speci c type of airway in amma on might improve the pa ent’s prognosis drama cally (preserved lung func on, improved quality of life). In order to be able to iden fy pa ents who are eligible for targeted treatments (e.g. mepolizumab, dupilumab), biomarkers of airway in amma on pathways are needed. Whether these markers are in uenced by asthma phenotype is unknown. Especially for pa ents with a recent-onset of adult asthma predictors of increased asthma severity, exacerba ons and remission are not known. Therefore, research on the prognosis of adult-onset asthma is required. This led to the following research ques ons for the present thesis:
1. Literature overview of adult-onset asthma prognosis.
2. Di ers the diagnos c accuracy of surrogate markers of airway eosinophilia between
adult-onset asthma phenotypes?
3. How accurate are surrogate markers of airway eosinophilia in detec ng sputum
eosinophils in a general asthma popula on?
4. Which factors predict remission and persistence of adult-onset asthma?
5. Which factors determine an increase in asthma severity?
6. What are the predictors of frequent asthma exacerba ons in adult-onset asthma, and
do these di er between for example smokers and never smoker?
The content of this thesis is mainly based on data of the Adonis-study (Adult-onset Asthma and In ammatory Sub-phenotypes). In this prospec ve observa onal study, 200 adult pa ents with a recent diagnosis (<1 year) of asthma were included. These pa ents were extensively characterized with regard to clinical, func onal and in ammatory parameters. Pa ents were asked to par cipate in the follow-up phase as well, with yearly visits to take history, spirometry and peripheral blood. A er 4-5 year a reassessment of the baseline parameters was performed. In addi on, a second database was set-up in which Adonis-study baseline
GENERAL INTRODUCTION AND AIMS
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