Effects of transcutaneous electrical nerve stimulation on the salivary flow of patients with hyposalivation induced by radiotherapy in the head and neck region-A randomised clinical trial

摘要

Hyposalivation is a frequent complication after treatment with radiotherapy. To evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) on the hyposalivation assessed through stimulated salivary flow (SSF). In this clinical trial, 68 patients (with hyposalivation) were randomly assigned to control (n = 31) or TENS (n = 37) group. Participants in control group received habitual care, while those in TENS group received 8 sessions (20 minutes each) delivered twice a week for four weeks. The electrodes were attached over the skin covering the salivary glands. The electric pulse was adjusted at a frequency of 50 Hz, pulse width of 250 mu s and as intense as tolerated. SSF was evaluated through sialometry. Self-perception of salivary flow (SPSF) and quality of life (QL) was evaluated prior to, during and at 1, 3 and 6 months after treatment. Although no changes were observed in the control group for SSF at any timepoints, TENS group showed a progressive increase in SSF from the third session until the end of the treatment. Significant improvements were also found in SPSF, especially when the SSF reached values >= 0.7 mL/minute. The most expressive results were evident at 6 months after treatment so that SSF, SPSF and QL remained significantly higher (F = 9.5, P = 0.0001; H = 143.77, P chi(2) = 9.162, P = 0.02, respectively). TENS was effective at improving hyposalivation. The benefits on SSF, SPSF and QL give base to a promising therapeutic strategy for patients with hyposalivation after radiotherapy treating head and neck cancer.