Reduced pain and analgesic use after acoustic binaural beats therapy in chronic pain - A double-blind randomized control cross-over trial.

Background: Binaural Beats (BB) consist of two artificial acoustic stimuli with different frequency, presented simultaneously but independently to each ear. The human brain perceives and synchronizes to this frequency difference (entrainment). Aim of this study was to test the hypothesis that brain entrainment to a lower function rhythm, with BB application, can decrease pain perception and analgesic medication use, in chronic pain patients.

Methods: In a double blind, randomized, cross-over trial, BB at 5Hz (theta rhythm) were applied for 30 minutes, under simultaneous electroencephalogram recordings, followed by liberal, on demand use by chronic pain patients for a week, compared to sham stimulation (SS). Pain as the main outcome (numeric scale, NRS), stress (STAI) and medication usage (defined daily doses, DDD) were assessed at baseline, 30 minutes and week's end.

Results: Perceived pain (NRS) was significantly reduced in BB intervention (5.6±2.3 to 3.4±2.6, p<0.001), compared to SS (5.2±2.1 to 4.8±2.3, p=0.78), during the first 30-minute phase, as well as at the week's end (to 3.9±2.5 compared to 5.5±2.6 respectively, p<0.001). The mean EEG theta power at 5Hz was significantly increased only during BB application. Stress was significantly reduced at 30 minutes in both interventions but remained reduced only in the BB group at the week's end. Analgesic medication consumption (DDD, g) during the week was significantly less in the BB intervention (3.9±3.7 vs. 4.6±4.1, p<0.05), while reporting equal to SS mean levels of pain.

Conclusions: Acoustic BB reduced pain intensity, stress and analgesic use, compared to SS, in chronic pain patients.

Significance: This study provides evidence that theta rhythm binaural beats can alleviate pain intensity, both after a brief 30 minute and a longer one week on-demand intervention. The subsequent significant reduction in analgesic medication consumption in chronic pain patients' daily living could offer a valuable tool, augmenting the effect of existing pain therapies.