[Bronchitis and emphysem: which is the primary condition? (author's transl)]

Chronic obstructive lung disease conprises 2 groups of diseases which have a different pathogenesis and require different therapy: 1. Chronic bronchitis with secondary emphysema. 2. Primary emphysema complicated by bronchitis. A differentiation between these 2 groups of patients is possible on the basis of lung function tests except in patients with complications, in whom long-term observation is required for clarification of the diagnosis. Separation of these conditions is also of importance in epidemiological studies of chronic bronchitis.