Page 124 - ADULT-ONSET ASTHMA PREDICTORS OF CLINICAL COURSE AND SEVERITY

ADULT-ONSET ASTHMA – PREDICTORS OF CLINICAL COURSE AND SEVERITY
METHODS
PATIENTS AND DEFINITIONS
Two hundred pa ents with adult-onset asthma were recruited from the outpa ent pulmonary clinics of one academic hospital (AMC, Amsterdam) and two secondary care hospitals in the Netherlands. One in Amsterdam (St Lucas-Andreas Hospital) and one in Hoofddorp, a municipality 20 kilometres from Amsterdam (Spaarne Hospital). All the study measurements were conducted at the AMC. All pa ents had to have a recent (<1 year) diagnosis of asthma. Adult-onset asthma was de ned as asthma with an onset of the disease at >18 years of age. Asthma diagnosis was based on typical symptoms and reversibility in FEV1 of > 12% of predicted value and/or a posi ve inhaled methacholine provoca on test (PC20 < 8mg/ml).9
Pa ents were excluded if they had a self-reported history of childhood asthma or other chronic respiratory diseases in childhood, frequent episodes of dyspnea as a child, or use of bronchodilator or other asthma medica on in childhood.
Current smoking and ex-smoking were allowed. Pa ents with a smoking history of >10 pack years were included only if they showed reversibility in FEV1 ≥12% of the predicted value, and had a normal di usion capacity (DLCO >80%).
The study was approved by the AMC Medical Ethics Board. All par cipants were informed and gave wri en informed consent. The study was registered in the Dutch trial register (NTR1846).
STUDY DESIGN
This study was part of the ADONIS-study (Adult-onset asthma and inflammatory subphenotypes), a longitudinal prospec ve cohort study in adults with new-onset asthma. At baseline, pa ents underwent comprehensive assessment of clinical symptoms, lung func on, markers of in amma on (exhaled nitric oxide, blood and sputum eosinophils), atopy, sinus CT scan and nasal endoscopy. Therea er, they were monitored by their own trea ng physician at regular intervals. A er two years pa ents were reassessed in our laboratory, with regard to clinical symptoms, lung func on, medica on requirement and markers of in amma on (frac on exhaled nitric oxide and blood eosinophils).
CLINICAL MEASUREMENTS
A comprehensive history was taken and physical examina on was performed. In addi on, pa ents completed self-reported ques onnaires including the Asthma Control Ques onnaire (ACQ-6),10 and Sino-nasal Outcome Test (SNOT-22).11
LUNG FUNCTION MEASUREMENTS
Lung func on measurements were performed in the lung func on laboratory according to interna onal recommenda ons with a daily calibrated spirometer (MasterScreen PFT, Jaeger,
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