Randomized, controlled study of inhaled fluticasone propionate, oral administration of prednisone, and environmental management of horses with recurrent airway obstruction.
OBJECTIVE
To determine whether administration of glucocorticoids provides additional benefits to environmental management of horses with recurrent airway obstruction (RAO).


METHODS
28 horses with RAO.


METHODS
Horses were classified as having mild, moderate, or severe RAO. Within each category, horses were randomly assigned to receive inhaled fluticasone propionate, inhaled control substance, or oral administration of prednisone. During the 4-week study, horses were maintained outdoors and fed a pelleted feed. Clinical scores, pulmonary function, results of cytologic examination of bronchoalveolar lavage fluid (BALF), and adrenal gland function were determined before and 2 and 4 weeks after initiation of treatment.


RESULTS
Clinical score and pulmonary function of all RAO-affected horses improved during the treatment period. After 4 weeks, clinical scores and pulmonary function of horses treated with a glucocorticoid were not different from those for the control treatment. In horses with severe RAO, treatment with fluticasone for 2 weeks resulted in significantly greater improvement in pulmonary function, compared with pulmonary function after treatment with prednisone or the control substance. Treatment with a glucocorticoid for 4 weeks and a low-dust environment did not have any effect on cellular content of BALF Treatment with prednisone for 2 weeks resulted in a significant decrease in serum cortisol concentration, compared with concentrations after administration of fluticasone or the control substance.


CONCLUSIONS
Environmental management is the most important factor in the treatment of horses with RAO. Early treatment with inhaled fluticasone can help accelerate recovery of horses with severe RAO.
Couëtil
Laurent L
LL
Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
Chilcoat
Clayton D
CD
DeNicola
Denis B
DB
Clark
Shawn P
SP
Glickman
Nita W
NW
Glickman
Lawrence T
LT
D000704:Analysis of Variance; D000730:Androstadienes / Q000627:therapeutic use*; D000818:Animals; D018893:Bronchoalveolar Lavage / Q000662:veterinary; D004777:Environment; D000068298:Fluticasone; D006734:Horse Diseases / Q000188:drug therapy*; D006736:Horses; D006854:Hydrocortisone / Q000097:blood; D011241:Prednisone / Q000627:therapeutic use*; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy / Q000662:veterinary*; D012129:Respiratory Function Tests / Q000662:veterinary
D000730:Androstadienes; D000068298:Fluticasone; D011241:Prednisone; D006854:Hydrocortisone