1. 연구 형태
다기관 전향적 연구, 환자들이 등록 이전에 최소 6개월의 follow-up이 있어야함.
2. cohort group
U-BIOPRED에서 정이한 severe asthma는 airtflow reversibility와 airway hyperresponsiveness 혹은 감소하는 것 FEV1 of 12% predicted, tapering maintenance treatment후 4주이내의 200ml감소. 4가지 그룹으로 모음
(1) Group A:12개월간 non-smoker with 5 pack-year smoking history, with asthma and uncontrolled sympoms odfineo occording to gina and frequemt exacerbations oespite high-dose inhaled corticosteroios.
(2) Group B: Group A랑 동일하나 현재 스모커나 ex-smoker
(3) Group C: non-smoker with mile/moderate asthmatics. controlled or partially controlled sympotms, whilst receiving a dose of <500 microgram fluticasone propionate/day or equivalent
(4) Group D: healthy non-smoking asthmatics. No history of asthma or wheeze, no chronic respiratory disease, nonsmoker for at least the past 12 months and their pre-bronchodilator FEV1 was >= 80% pred.
3. Protocal and assessment
대략 천식환자가 받아야할 테스트들에 대한 설명이 있음
4. statistical analysis
data는 평균이나 중앙값으로 요약되고 nonsymmetrical variable은 positive skew이거나 log-transformed되었다.
Missing value were not imputed. p=value는 general linear model이나 혹은 logidstic model로 계산되었다.
5. Result
6. spirometry
SAn/SA is lower than other groups in FEV1, FVC, FEV1/FVC
7. medication
SAn/SAs/ex is higher rate of medication than other groups.
8. atopy and comorbidity
There was a higher incidence atopy in the four groups.
9. Blood and sputum in biomarkers
blood eosinophil counts
blood neutrophil counts
10. Exhaled nitric oxide
FeNo
11. Discussion