To determine whether treatment with Mg2+ improves the outcome of idiopathic sudden hearing loss and to investigate which variables influence its prognosis.
Prospective randomized study.
Department of Otolaryngology–Head and Neck Surgery, Rambam Medical Center, Haifa, Israel.
The study group included 133 patients. Sixty patients were treated with carbogen inhalation, and 73 were treated with a combination of carbogen inhalation and intravenous MgSO4.
The mean improvement rate was 66.4% in the Mg2+ group and 49.9% in the carbogen group (p < 0.01). Recovery was achieved in 35 patients (48%) in the Mg2+ group and only in 19 patients (31.6%) in the carbogen group (p < 0.01). Significant improvement was seen in 20 patients (27.4%) in the Mg2+ group and in 14 patients (23.3%) in the carbogen group. Partial improvement was seen in eight patients (10.9%) in the Mg2+ group and in 12 patients (20%) in the carbogen group. No improvement was achieved in 10 patients (13.6%) in the Mg2+ group and in 15 patients (25%) in the carbogen group. Patients with vestibular symptoms had a poorer hearing outcome compared to those without vertigo (p < 0.04). Patients who commenced the treatment 8 days or more after onset had poorer recovery as compared with those who started treatment earlier (p < 0.03), regardless of the treatment regimen. Age, sex, and tinnitus had no significant impact on hearing recovery.
We found that Mg2+ improved hearing recovery in cases of idiopathic sudden hearing loss. Vertigo and treatment delay beyond 8 days were poor prognostic factors for recovery.