A New Treatment for Vestibular Neuritis

Abstract & Commentary

Synopsis: Methylprednisolone significantly improves the recovery of peripheral vestibular function in patients with vestibular neuritis, whereas valacyclovir does not.

Source: Strupp M, et al. Methylprednisolone, Valacyclovir, or the Combination for Vestibular Neuritis. N Eng J Med. 2004;351:354-361.

The present paper studied the treatment of vestibular neuritis. It was assumed that 1 potential mechanism is reactivation of herpes simplex virus type 1 (HSV-1) infection. If this is indeed the case, corticosteroids, antiviral agents, or a combination of the 2 might prove to be effective in improving the outcome in these patients. This has been shown to be the case with Bell’s Palsy. Strupp and colleagues, therefore, performed a prospective, randomized, double-blind, 2-by-2 factorial trial, in which patients with acute vestibular neuritis were randomly assigned to placebo, methylprednisolone, valacyclovir, or the combination of methylprednisolone plus valacyclovir. The vestibular function was determined by caloric irrigation, to determine the degree of vestibular paresis, which was done initially within 3 days after the onset of symptoms and then 12 months afterwards. Strupp et al randomized 141 patients. Thirty-eight received placebo, 35 received methylprednisolone, 33 received valacyclovir, and 35 received the combination of methylprednisolone plus valacyclovir. The methyprednisolone was administered at an initial dose of 100 mg on days 1 through 3, and 80 mg on days 4 through 6, 60 mg on days 7 through 9, 40 mg on days 10 through 12, 20 mg on days 13 through 15, 10 mg on days 16 through 18, and 10 mg on days 20 and 22.

At the onset of symptoms, there was no significant difference amongst the groups in the severity of vestibular paresis. At the 12 month follow-up point, the improvement in peripheral vestibular function was 39.6 ± 28.1 percentage points in the placebo group, 62.4 ± 16.9 percentage points in the methylprednisolone group, 36.0 ± 26.7 percentage points in the valacyclovir group, and 59.2 ± 24.1 percentage points in the methylprednisolone plus valacyclovir group. Analysis of variance showed that methylprednisolone, but not valacyclovir, was effective in improving the patients over the placebo group. The combination of methylprednisolone and valacyclovir was not superior to corticosteroid therapy alone. Strupp et al concluded that methylprednisolone significantly improved the recovery of peripheral vestibular function in patients with vestibular neuritis, whereas, valacyclovir does not.

Commentary

Vestibular neuritis is the second most common cause of peripheral vestibular vertigo, following benign paroxysmal positional vertigo. It accounts for 7% of the patients who present to outpatient clients specializing in the treatment of dizziness. The key signs and symptoms are the acute onset of sustained rotatory vertigo, postural imbalance, with a tendency to fall towards the affected ear with the eyes closed, Romberg’s sign, horizontal spontaneous nystagmus towards the unaffected ear, with a rotational component and nausea. Caloric testing of the ear, which is affected, shows ipsilateral hyporesponsiveness or non-responsiveness. The cause of vestibular neuritis is unknown, but could possibly be due to a viral cause. Evidence in favor of this has been circumstantial. HSV-1 DNA has been detected on autopsy, with the use of polymerase chain reaction, in about 2 of 3 human vestibular ganglia. This suggests that the vestibular ganglia are latently infected by HSV-1. The recovery from vestibular neuritis is usually incomplete. In view of this, a treatment, which would improve the long-term outcome, is greatly needed. The present report that methylprednisolone is effective, therefore, is of great interest. — M. Flint Beal

Dr. Beal, Professor and Chairman; Department of Neurology; Cornell University Medical College New York, NY, is Editor of Neurology Alert.