Table of Contents Author Guidelines Submit a Manuscript
Canadian Respiratory Journal
Volume 9, Issue 5, Pages 307-312
http://dx.doi.org/10.1155/2002/746808
Original Article

The Relationship among the Inspiratory Muscle Strength, the Perception of Dyspnea and Inhaled Beta2-Agonists in Patients with Asthma

Paltiel Weiner, Rasmi Magadle, Marinella Beckerman, and Noa Berar-Yanay

Department of Medicine A, Hillel-Yaffe Medical Center, Hadera,, Israel

Copyright © 2002 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

BACKGROUND: It is well documented that the perception of dyspnea (POD), subjectively reported by patients, is related to the activity and strength of the inspiratory muscles, and influences the use of 'as needed' beta2-agonists.

STUDY OBJECTIVE: To investigate the relationship among the increase in inspiratory muscle strength after specific inspiratory muscle training, beta2-agonist consumption and the POD in patients with persistent, mild to moderate asthma.

METHODS: Inspiratory muscle strength, daily beta2-agonist consumption and the POD were measured in 30 patients with mild to moderate asthma. Patients were then randomly assigned to two groups: one group received specific inspiratory muscle training until an increase of more than 20 cm H2O was reached, and one group was a control group and received sham training. Inspiratory muscle strength, the POD and daily beta2-agonist consumption were assessed during and after the training period.

RESULTS: There was no good correlation between the baseline maximal inspiratory pressure and the POD, or between the baseline maximal inspiratory pressure and the mean daily beta2-agonist consumption. However, there was a significant correlation between the POD and the mean daily beta2-agonist consumption. The increase in inspiratory muscle strength after the inspiratory muscle training was closely correlated with the decrease in the POD (P<0.001) and the decrease in beta2-agonist consumption (P<0.001).

CONCLUSIONS: The present study shows that, in patients with mild to moderate, persistent asthma, there is a correlation between the POD and the mean daily beta2-agonist consumption. When the inspiratory muscles are strengthened, there is a significant decrease in the POD and in beta2-agonist consumption.