Oral steroid treatment for idiopathic sudden sensorineural hearing loss

Objectives:

To describe the efficacy of long-term oral steroids in idiopathic sudden sensorineural hearing loss (ISSHL), and to explore potential prognosis factors, the relationship of hearing recovery outcome, and the recovery time-course in ISSHL.

Methods:

In this retrospective study, we analyzed 215 cases diagnosed with idiopathic unilateral sudden deafness between January 2003 and December 2012 at a regional hospital in southern Taiwan. All of them received oral steroid therapy and were followed for at least 3 months.

Results:

Young age, the presence of no other disease (diabetes, hypertension, or cardiovascular disease), treatment within 7 days of the onset of ISSHL, mild hearing loss, and audiograms with ascending curves had a statistically significant better hearing recovery. The average pure-tone audiometry (PTA) was 67.8±23.9 dB initially, and was improved between one month (51.6±28.7 dB) and 2 months post treatment (49.7±28.6 dB). The average last-visit PTA was 49.9±29.2 dB.

Conclusion:

Approximately one third of patients had full recovery in hearing, one third had partial recovery, and approximately one third did not recover from hearing loss. In addition, the hearing level remained relatively stable following 2 months of treatment. More than 2 months of oral steroid therapy for ISSHL is not recommended because no additional benefits were evidenced.Idiopathic sudden sensorineural hearing loss (ISSHL) is defined as a sensorineural hypoacusis of at least 30 dB over 3 consecutive speech frequencies, occurring within 3 days. It is considered to be an otologic emergency, and the incidence has been estimated to range from 3.9 to 27.5 per 100,000 persons per year.1 Although the exact cause is still unknown, it has been hypothesized to be caused by viral infection of the labyrinth or cochlear nerve, vascular insult, intra labyrinthine membrane rupture, and autoimmunity.2 Owing to the variations in the etiopathogenesis of ISSHL, different therapeutic strategies have been developed. Steroids or in combination with vasodilators, plasma expanders, diuretics, anticoagulants, antiviral, vitamins, cytotoxic medications, hyperbaric oxygen, stellate ganglion block, and inhaled carbogen, have become the most widely accepted treatment options.2-7 However, the length of oral steroid therapy had not been well established. Most of the studies reported the length of steroid therapy ranging between 5-24 days.2-7 Although little is known about the time course of hearing loss for most patients, improvement in hearing can be anticipated only during the first 1-2 months. Therefore, this study investigated progression in recovery from sudden hearing loss, and the optimal treatment duration with oral steroids.