Hypnosis for the Management of Anxiety and Dyspnea in COPD: A Randomized, Sham-Controlled Crossover Trial

Abstract

Background: Patients with chronic obstructive pulmonary disease (COPD) are prone to dyspnea, increased respiratory rate and other anxiety-inducing symptoms. Hypnosis constitutes a complementary procedure capable of improving subjective feelings of anxiety.

Objective: Assessing the efficacy of a 15-minute hypnosis intervention for immediate improvement of anxiety in severe COPD patients.

Methods: Twenty-one participants, COPD patients (mean FEV1 < 32.3%), were randomly assigned to two individual sessions in crossover (sham and hypnosis, 24-h washout period, arms: hypnosis-sham [n=11]/sham-hypnosis [n=10]). We tracked pre- and post-intervention anxiety (STAI-6 score) as primary endpoint.

Results: Nineteen (90.5%) participants completed the study. Anxiety diminished significantly after hypnosis (STAI-6 scores -23.8% [SD = 18.4%] hypnosis vs -3.1% [32.8%] sham; χ²=8, P<0.01, Bayes Factor 5.5). Respiratory rate also decreased after hypnosis. Improvements in SpO2 and Borg exertion scores were registered after both conditions.

Conclusion: A 15-minute hypnosis session improved participants' anxiety and lowered respiratory rate (as opposed to sham). Improvements in anxiety were correlated with an alleviation in respiratory strain. Results imply that hypnosis can contribute to the improvement of anxiety levels and breathing mechanics in severe COPD patients.

Registration id: ISRCTN10029862.

Keywords: COPD; anxiety; complementary care; depression; dyspnea; hypnosis.

Figure 1

CONSORT chart and study design. (A) CONSORT flowchart. After screening and preselecting all CHB admitted patients, 21 patients were recruited and randomly assigned to one of four pairs of investigators, in charge of administering the sessions and collecting the data. Investigators were all psychologists, pneumonologysts and/or palliative care health practitioners, trained in hypnosis. Session order was counterbalanced across pairs of investigators. Of 21 patients, 2 failed to complete the trial (1 for consent withdrawal, 1 for technical issues). (B) Outline. Detailed outline showing the observation time and collected measures. (C) Outline of Hypnosis and Sham-controlled interventions. Interventions were scripted, of equal duration, and controlled for environment and body posture. Sessions were introduced as “Attention exercises” during the motivation phase. Hypnosis was then identified as “Hypnosis”, and Sham was identified as “Active listening exercise”. Both interventions were controlled for differences in expectation and motivation.

Figure 2

Summary of main hypnosis and sham effects. (A) STAI−6 before and after intervention. (A). STAI-6 scores. Changes in anxiety after sham and hypnosis sessions. Anxiety decreased significantly after hypnosis (P<0.0001, BF=1212), but not after sham (P=0.18, BF=0.4). (B) ΔSTAI−6 across sessions. Outcome of the hypnosis session (mean % of change = −23.8%, SD=18.4) was significantly different from sham (mean % of change = −3.11%, SD=32.8) (P<0.01, BF=5.5). (C). ΔSTAI-6 regressed against ΔBorg across conditions. Indexes were positively correlated, independently of intervention type, implying that improvements in anxiety were positively associated with relief in respiratory strain (main effect ΔBorg, χ²=5, DF=1, P<0.05; main effect Intervention Type, χ²=5, DF=1, P<0.05; interaction ΔBorg x Intervention Type, χ²=1, DF=1, P=0.32). (D) ΔRR regressed against ΔSpO2 across conditions. SpO2 levels increased after both hypnosis and sham interventions, but were associated with increases in RR only after sham (main effects Intervention Type, χ²=31, DF=1, P<0.0001; main effect ΔSpO2, χ²=25, DF=1, P<0.0001; interaction ΔSpO2 X Intervention Type, χ²=22, DF=1, P<0.01). (Significance thresholds: **P < 0.01; ***P < 0.0001).