Breathing pattern changes in refractory chronic cough with physiotherapy speech and language therapy intervention

Introduction: Physiotherapy, speech and language therapy intervention (PSALTI) improves cough symptoms for refractory chronic cough. Breathing pattern retraining exercises are integral to PSALTI. However the effect of PSALTI on breathing pattern characteristics and subsequent effect on cough is unknown. Methods: Secondary analysis of the PSALTI RCT. 52 participants underwent breathing pattern assessment at baseline. 20 random participants underwent breathing pattern re-assessment after 4 weeks of treatment (4w). Breathing pattern, route of breathing and region of most movement (upper chest movement (UCM) or abdominal movement (ABM)), was assessed whilst sitting, over 1 minute, by a Physiotherapist. Within group analyses were assessed by T tests. Results: At baseline 51% (n=27) of all participants had UCM, albeit normal respiratory rate and nasal route of breathing. Four of 11 PSALTI and 4 of the 9 control participants had ABM at baseline. All 11 PSALTI participants had ABM by 4w compared to only 5 of 9 controls. In the 7 PSALTI participants who altered their breathing pattern to ABM, significant changes were observed at 4w in cough QOL (LCQ Mean difference (MD) 3.94 95%CI (1.69 to 6.19), p=0.005), VAS severity (MD -25.67 95%CI (-51.03 to -0.30), p=0.045)) and borderline significant change in cough frequency (log MD (log95%CI) -0.34 (-0.68 to 0.00), p=0.051). No significant improvement in cough was found in those who had ABM at baseline. Conclusion: Breathing pattern disorder is prevalent in refractory chronic cough. Breathing pattern retraining may be an important PSALTI mechanism of action. PSALTI may be more effective in patients with breathing pattern disorders.