Effects of fluticasone propionate inhalation on levels of arachidonic acidmetabolites in patients with chronic obstructive pulmonary disease

BACKGROUND: In smoking COPD patients the bronchoalveolar lavage (BAL) fluid contains high numbers of inflammatory cells. These cells might produce ara chidonic acid (AA) metabolites, which contribute to inflammation and an inc reased bronchomotor tone. Aims: To investigate levels of AA metabolites in BAL fluid, before and afte r inhaled glucocorticoid therapy: fluticasone propionate (FP) 1 mg per day, or placebo. Methods: A double-blind placebo controlled trial lasting six months. COPD p atients were selected by clinical criteria and the presence of bronchial hy perresponsiveness (BHR). Lung function was recorded and in BAL fluid we cou nted cell numbers and measured LTB4, LTC4/D-4/E-4, PGE(2), 6kPGF(1)alpha, P GF(2)alpha and TxB(2). A control group consisted of asymptomatic smokers (n =6). Results: Paired data were obtained from 9 FP treated and 11 placebo patient s. BAL cells were almost exclusively alveolar macrophages. In patients and controls both cellularity and levels of AA metabolites were equal. Cell num bers did not change after treatment. Statistically significant decreases af ter FP therapy were noticed for PGE(2) (30%), 6kPGF(1)alpha (41%) and PGF(2 )alpha (54%). Conclusions: In COPD, the capability of inflammatory cells to produce certa in AA metabolites was decreased after inhaled FP treatment. This result is discussed in its relation to clinical effects, the influence of smoking, an d the results of an earlier, similar study in asthma patients.