By David Douglas
NEW YORK (Reuters Health) – Treatment with the inhaled corticosteroid budesonide increases the perception of bronchoconstriction in certain asthmatics, Australian researchers report in the January 1st issue of the American Journal of Respiratory and Critical Care Medicine.
Lead author Dr. Cheryl M. Salome told Reuters Health that of particular interest is "that it is possible to alter the ability of asthmatic patients to perceive changes in their airway function. This argues against the idea that some patients are inherently poor perceivers."
Dr. Salome and colleagues, at the University of Sydney, studied 35 patients with poorly controlled asthma. They were randomized to daily treatment with budesonide 1600 or 3200 mcg for 8 weeks. All subjects then continued with 1600 mcg per day for a further 8 weeks, and doses were tapered thereafter.
At baseline and at intervals for up to 72 weeks, subjects underwent histamine challenge. Borg scores for breathlessness were recorded and perception was estimated by plotting the score against the percentage drop in lung function (FEV1).
The Borg/FEV1 slope increased significantly at 8 weeks and subsequently remained at that level. Furthermore, this response did not differ significantly between treatment groups and was not related to factors including baseline FEV1, airway responsiveness, and blood eosinophils. This was also the case whether or not subjects had been taking inhaled corticosteroids at the time of study entry.
The researchers conclude that "further studies are needed to determine whether the perception of induced airway narrowing is related to how patients perceive symptoms in a clinical setting."
Nevertheless, Dr. Salome added that "because perception probably changes as clinical status changes, doctors may need to be particularly careful to make objective measurements when they are altering a patient's treatment regimen, as symptoms may be an unreliable guide to clinical status at these times."