Asthma is an airway disease characterized by variable narrowing of the airways, inducing respiratory symptoms like wheezing or dyspnea. The airways can be divided in large and small airways. Nowadays, new inhalation medication with small particles is available for patients with asthma. The advantage of small particles is their ability to reach the small airways and probably affect them beneficially. However, it is still not clear if patients with asthma have symptoms of small airways dysfunction and consequently if we need to treat small airways dysfunction. This thesis investigated this relation using a literature review and clinical studies. We showed that small airways dysfunction is related to more clinical symptoms, like e.g. worse control of asthma, presence of exercise-induced asthma, and increased reactivity of the airways to constrict in response to nonspecific stimuli like fog. Next, we developed a preliminary questionnaire that may contribute to the assessment of patients with or without small airway dysfunction. This questionnaire is now being tested and validated in a large cohort of asthma patients. We also developed a new provocation test with large and small particles of adenosine powder in order to identify patients who will probably benefit of inhalation medication with small or large particles. We found that a challenge with adenosine dry powder is able to induce response of the large and small airways response. Fur future research we would like to use imaging techniques in order to better understand the exact sites of medication deposition and airway response.
|Qualification||Doctor of Philosophy|
|Place of Publication||[S.l]|
|Publication status||Published - 2015|