Tiotropium (18μg once q.d)
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Maintain the original regimen
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No washout, go directly into randomization
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Budesonide/formoterol (160μg/4.5μg once or twice b.i.d)
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Tiotropium (18μg once q.d) + budesonide/formoterol (160μg/4.5μg once or twice b.i.d)
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No use of inhaled medication
|
Tiotropium (18μg once q.d)
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Four weeks
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Anticholinergic agents except tiotropium
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Inhaled corticosteroids only
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Tiotropium (18μg once q.d) + budesonide/formoterol (160μg/4.5μg once or twice b.i.d)
|
Inhaled β2-agonist only
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ICS/LABA except budesonide/formoterol
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LAMA+ICS/LABA except Tiotropium + budesonide/formoterol
|