Patients with COPD experience exacerbations that are a major cause of morbidity. Exacerbations are associated with increased airway and systemic inflammation and those experiencing frequent exacerbations demonstrate increased inflammation in the stable state. Tiotropium has been shown to reduce exacerbation frequency and it might be postulated that this is due to a reduction in inflammation. The study will compare airway inflammation and exacerbation frequency in patients with COPD on tiotropium or placebo.

Patients with COPD will be randomised to tiotropium or placebo in addition to their usual medication. They will be followed prospectively over 1 year and provide sputum for quantification of IL-6 and IL-8 at baseline and at 3 monthly intervals.Serum IL-6 will also be quantified at baseline and over the year. Changes in inflammatory markers will be assessed by analysis of area under the curve of log transformed data. Exacerbation frequency will be calculated from patient diary cards using a previously validated symptom-based exacerbation definition.

Inclusion Criteria:

• diagnosis of COPD,
• FEV1 < 80% predicted,
• minimum 10 pack year smoking history

Exclusion Criteria:

• asthma,
• atopic disease,
• eosinophilia,
• history of malignancy,
• history of clinically significant pulmonary disease