Sequential Multilocus Repetitive Transcranial Magnetic Stimulation for Treatment of Tinnitus With and Without Comorbid Major Depressive Disorder

Objective: Repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for tinnitus, although outcomes are highly variable. We previously described a multilocus sequential rTMS treatment protocol for tinnitus involving stimulation of both prefrontal and auditory targets. In this study, we report results using this approach in an open-label treatment study of tinnitus with and without comorbid major depressive disorder (MDD).

Materials and methods: Forty patients with chronic tinnitus (mean age 56 years, ten female) and with (n = 17) or without (n = 23) MDD received multilocus rTMS administered sequentially to 1) left dorsolateral prefrontal cortex, followed by 2) auditory cortex (Heschel's gyrus). Patients completed weekly self-report ratings using the Tinnitus Functional Index (TFI) and Tinnitus Handicap Inventory, and patients with MDD completed the Inventory of Depressive Symptomatology Self-Report 30-item.

Results: Patients showed significant mean improvement in tinnitus at sessions 5 (mean TFI improvement 6.8 points ± 12.2, p = 0.002) and 10 (mean improvement 9.2 points ± 14.1, p = 0.002), with 48% of patients responding within ten treatment sessions. Responders were significantly older than nonresponders (61.5 ± 15 years vs 51.3 ± 16 years), and there was a trend toward decreased likelihood of response in subjects with comorbid MDD compared with subjects without comorbidity (odds ratio = 0.28, p = 0.06). Patients with comorbid MDD reported significantly less improvement after ten sessions than did those with tinnitus alone (4.3 ± 10.3 vs 14.7 ± 15.0 points, p = 0.04). Post hoc analyses suggested that the comorbid group achieved improvement comparable to that of the tinnitus-only group after 30 treatments.

Conclusions: Patients showed significant improvement in tinnitus from multilocus sequential rTMS treatment, and those with tinnitus alone improved more quickly. Those with depression who continued rTMS through a full 30-session course further improved, indicating that tinnitus with comorbid MDD may respond with extended treatment.