The effects of threshold inspiratory muscle training in patients with chronic obstructive pulmonary disease: A randomised experimental study.

AIMS AND OBJECTIVES

To investigate the effects of threshold inspiratory muscle training in patients with stages II through IV chronic obstructive pulmonary disease using maximum inspiratory pressure, baseline dyspnoea index, 6-minute walk test and quality of life.

BACKGROUND

A threshold inspiratory muscle training device provides pressure for inspiratory muscle strength, but there is limited information on the effects of threshold inspiratory muscle training starting at low pressure training.

DESIGN

Randomised experimental design.

METHODS

A total of 55 patients completed this study between September 2013-April 2014. The experimental group (n = 27) was provided medical treatment and routine care, along with five sessions of threshold inspiratory muscle training per week (21-30 min per session), accompanied by a progressive increase in the pressure threshold over a period of 8 weeks. The control group (n = 28) was provided medical treatment and routine care only, without intervention. In the inferential analysis, p values <.05 were considered to indicate statistical significance.

RESULTS

After 8 weeks in the experimental group, mean maximum inspiratory pressure improved by -17.6 ± 0.18 cmH O, mean 6-minute walk test improved by 47.8 ± 1.46 m, and the baseline dyspnoea index increased from 4.48 ± 2.12 points to 9.0 ± 2.27 points. These data and quality of life were statistically different between the experimental and the control groups (p < .05).

CONCLUSIONS

The threshold inspiratory muscle training can reduce patients' difficulties with respect to daily activities, thereby reducing the burden on the family, and improving prognosis in patients with moderate-to-very severe chronic obstructive pulmonary disease.