Behavioural modes of adherence to inspiratory muscle training in people with chronic obstructive pulmonary disease: a grounded theory study

Abstract
PURPOSE:
Our aim was to develop a theoretical account of the behavioural pattern of adherence to home-based inspiratory muscle training (IMT) in people with chronic obstructive pulmonary disease (COPD), performed as two daily sessions of 30 breaths with mechanical threshold loading.

METHODS:
This was a qualitative study based on the classic grounded theory method. We conducted interviews with people living with COPD recruited after completion of 6 weeks of outpatient pulmonary rehabilitation program in 2015. Concurrently, we generated data and performed analyses by means of constant comparative analysis and theoretical sampling that focused on the behavioural characteristics of adherence to IMT.

RESULTS:
We achieved theoretical saturation of substantive codes with 33 interviews, nine of which were with men. The participants' mean age and forced expired volume in the first second were 65 (SD 8) years and 59.1 (SD 13.9) percent of predicted, respectively. Seventeen participated in face-to-face interviews, and 16 participated in telephone interviews. The core category "Preserving Integrity" emerged as representative of the primary pattern of behaviour related to the inspiratory muscle-training regimen. Through this pattern, the participants resolved the main concern of losing integrity. Preserving Integrity involved three behavioural modes of adherence to home-based IMT: evading, misgiving, and involving modes.

CONCLUSIONS:
The participants' behavioural modes regarding adherence revealed patterns of both intended and unintended nonadherence. In particular, support offered by healthcare professionals should target people with unintended nonadherence and scepticism about the effects of IMT to maximise the possibility of adherence. Implications for rehabilitation When implementing inspiratory muscle training, healthcare professionals should be prepared to spend considerable time providing attention and support to participants who feel challenged during the execution of inspiratory muscle training. Support offered by healthcare professionals should target people with scepticism about the effects of inspiratory muscle training to maximise the possibility of adherence. Intended adherence to inspiratory muscle training appeared to be firmly rooted, which means that healthcare professionals can pay less attention to patients with strong intentions to ensure adherence.