The effect of mindfulness meditation on cough reflex sensitivity

Abstract

Background: Chronic cough is common, and medical treatment can be ineffective. Mindfulness is a psychological intervention that aims to teach moment-to-moment non-judgemental awareness of thoughts, feelings and sensations. Method: 30 healthy subjects and 30 patients with chronic cough were studied in two sequential trials. For both studies, cough reflex sensitivity to citric acid (C5) was measured on two occasions, with urge to cough rated following each inhalation; between challenges subjects were randomised to (1) no intervention, (2) mindfulness or (3) no intervention but modified cough challenge (subjects suppress coughing). For the healthy volunteers, measures were 1 h apart and mindfulness was practised for 15 min. For the patients with chronic cough measures were 1 week apart and mindfulness was practised daily for 30 min. Results: In healthy volunteers, median change (interquartile range (IQR)) in cough reflex sensitivity (logC5) for no intervention, mindfulness and suppression was +1.0 (0.0 to +1.3), +2.0 (+1.0 to +3.0) and +3.0 (+2.8 to +3.0) doubling concentrations (p = 0.003); there were significant reductions for both mindfulness (p = 0.043) and suppression (p = 0.002) over no intervention. In patients with cough, median change (IQR) in logC5 for no intervention, mindfulness training and voluntary suppression was 0.0 (21.0 to +1.0), +1.0 (20.3 to +1.0) and +1.0 (+1.0 to +2.0) doubling concentrations (p = 0.046); there was a significant reduction for suppression (p = 0.02) but not mindfulness (p = 0.35). Urge to cough did not change after mindfulness compared with control in either healthy subjects (p = 0.33) or those with chronic cough (p = 0.47). Conclusion: Compared with control, mindfulness decreased cough reflex sensitivity in healthy volunteers, but did not alter cough threshold in patients with chronic cough. Both groups were able to suppress cough responses to citric acid inhalation.Chronic cough, defined as cough lasting .8 weeks, has a prevalence of around 12% in the general population 1 and is associated with significant comorbidity including anxiety and depression.

Sensorimotor circuitry involved in the higher brain control of coughing

“…Less is known about the affective processing associated with airways irritation. Of interest, however is that individuals with respiratory disorders such as asthma or chronic cough have a significantly increased risk of developing mood and anxiety disorders, and it seems likely that this would be reflected in altered activity of the network components comprising this cognitive module [25-28]. …”

Clinical features of the urge-to-cough in patients with chronic cough

“…Subsequent studies have mostly assessed influences on the intensity of experimentally induced urge-to-cough. For example, viral upper respiratory tract infections and nicotine withdrawal in smokers [10,11] appear to enhance the urge-to-cough, whereas it can be depressed by exercise [12] and mindfulness relaxation techniques [13]. However, none of these studies have acknowledged or reported the somatic sensations evoked by inhaled irritants, only the compulsion to cough.…”

Tai chi mind-body exercise in patients with COPD: study protocol for a randomized controlled trial

“…This awareness may in turn complement other tai chi components that foster improved function (for example, improved posture, relaxation). Recent studies support that mindfulness training can impact interoceptive awareness of key COPD symptoms (such as dyspnea and cough) which may lead to better symptom management [62–64]. Inner awareness of moment-to-moment sensations also helps develop focused attention, providing a tool to manage distracting thoughts [65].…”