Background: Increased oxidative stress and bronchial inflammation are important mechanisms in the pathophysiology of COPD.
Aim: To investigate whether treatment with the inhaled corticosteroid fluticasone propionate (FP) or the anti-oxidative agent N-acetylcysteine (NAC) are effective in primary care patients.
Methods: The study was a 3-year placebo-controlled randomised controlled trial preceded by a 3-month washout and 2-week prednisolone pre-treatment. Patients were (ex-)smokers with chronic bronchitis or COPD. Interventions were inhaled FP 500microg b.i.d., oral NAC 600mg o.d., or placebo. Exacerbation rate and quality of life measured with the Chronic Respiratory Questionnaire (CRQ) were the primary outcomes, FEV(1) decline and respiratory symptoms secondary outcomes.
Results: 286 patients recruited from 44 general practices were randomised. Exacerbation rate was 1.35 times higher for NAC (p=0.054) and 1.30 times higher for FP (p=0.095) compared with placebo. CRQ total scores did not differ between NAC (p=0.306) or FP (p=0.581) treatment compared to placebo. Annual postbronchodilator FEV(1) decline was 64mL [SD 5.4] for NAC [p=0.569 versus placebo], 59mL [SD 5.7] for FP [p=0.935], and 60mL [SD 5.4] for placebo.
Conclusion: No beneficial treatment effects for either high-dosed inhaled fluticasone propionate or oral N-acetylcysteine were observed in our study population of patients with COPD or chronic bronchitis.