[Multivariate analysis of everyday handicap of patients with dizziness]

Comparative study of anti-vertiginous and anti-anxious drugs for the treatment of chronic vestibular patients with secondary anxiety

Background: Regarding the relationship between psychiatric disorders and dizziness, anxiety is the most frequently seen psychiatric disorder in dizzy patients. Objective: We compared the effects of anti-anxious benzodiazepines (loflazepate) and anti-vertiginous cholinergic antagonist (diphenidol) on the subjective symptoms in chronic vestibular patients with secondary anxiety. Methods: Forty-three patients who had chronic dizziness lasting more than three months due to organic vestibular diseases with secondary anxiety. Anxiety was evaluated by the State-Trait Anxiety Inventory (STAI). Subjective handicaps due to dizziness were assessed by the validated questionnaire consisted of 14 questions that were categorized into two physical and three emotional factors. During the initial six months of the study, 21 patients were treated by anti-anxious benzodiazepines (loflazepate, 2 mg/day) for four weeks, whereas anti-vertiginous cholinergic antagonist (diphenidol, 75 mg/day) was used for four weeks for other 22 patients during the later six months-period. Subjective handicaps and STAI were compared between pre- and post-treatment. Results: Loflazepate improved not only three emotional factors and state anxiety but also one of the physical factors. Diphenidol improved two physical factors but no emotional factors nor state and trait anxiety. Conclusions: Targeting for comorbid anxiety was beneficial for subjective symptoms of chronic dizziness with secondary anxiety.

Insufficient evidence for the effect of corticosteroid treatment on recovery of vestibular neuritis

The authors studied the effect of corticosteroid treatment on clinical recovery and recovery of vestibular function in patients with vestibular neuritis. The comprehensive search (March 29, 2012) yielded 496 original papers, of which 5 (including 199 patients) during full-text screening satisfied our eligibility criteria. Methods assessment showed that 1 study (30 patients) provided direct evidence and carried low risk of bias. Two studies properly reported on their random and concealed allocation of treatment. In 1 study, patients were not randomly allocated to treatment. Blinding of outcomes was lacking in 2 studies, whereas outcome data were clearly incomplete for 2 studies. Given the wide variety in outcome measures and scales and follow-up duration, the meaning of the size of reported effects is not clear. Therefore, the reported effects cannot simply be compared between studies, and this precludes pooling of study results. Still, there are large differences between studies in the size of the reported absolute effects after the placebo treatment. Moreover, the difference in effects between treatments is rather small and does not always favor corticosteroids. The moderate to high risk of bias of studies precludes firm conclusions, whereas the reported short-term effects on symptom recovery and improvement of peripheral vestibular function are too small to be clinically important. No long-term effect on symptom recovery has been shown. Recommendations or decisions for corticosteroid treatment in patients with vestibular neuritis cannot be based on current best evidence and therefore should be discussed with the patient.

[Dynamic vestibular compensation in vestibular peripheral diseases]

Vestibular compensation, or neuronal plasticity in the central vestibular system, is quite an important process in patients with acute unilateral peripheral vestibular disease, allowing them to lead a comfortable daily life when medical treatments fail to cure the peripheral vestibular function. Is the residual unilateral vestibular input from damaged vestibular endo-organs a positive or negative factor for the development of dynamic vestibular compensation in the central nervous system? To elucidate the true mechanism of vestibular compensation, we examined the ENG findings and dizziness handicap inventory questionnaire in patients with vestibular neuronitis (VN), sudden deafness with vertigo (SDV), Meniere's disease (MD) and acoustic tumor (AT) during remission of the vertigo attacks. We obtained neuro-otological findings from caloric tests and head shaking after nystagmus using ENG and information on motion-evoked dizziness in daily life using the questionnaire. There were no significant differences in the sex, age or canal paresis % (CP%) among the four groups. The results of the present study showed that dynamic vestibular compensation processes developed progressively in the order of patients with SDV, VN, MD and AT (Kruskal-Wallis : p < 0.05). This finding suggests that processes of dynamic vestibular compensation could be accelerated in patients with fixed vestibular lesions caused by SDV and VN more than in those with fluctuating vestibular functions caused by MD and AT. In patients with fixed vestibular lesions caused by SDV and VN, patients with lower CP% showed dynamic vestibular compensation (i.e. disappearance of head shaking after nystagmus (chi-square: p < 0.05) and motion-evoked dizziness (Mann-Whitney: p < 0.0005)) more rapidly than those with higher CP%. In patients with fluctuating vestibular functions caused by MD and AT, patients with lower CP% did not always develop dynamic vestibular compensation more smoothly than those with higher CP%.

Steroid effects on vestibular compensation in human

Vestibular neuritis (VN) rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. We experienced 36 patients with VN treated at our hospital, including cases in our previous preliminary report. To elucidate effects of steroid therapy both on the recovery of peripheral function and on the adaptation of central vestibular compensation, we examined caloric test and several questionnaires with two randomly divided groups, 18 steroid-treated and 18 nonsteroid-treated patients, over two years after the onset. These examinations revealed that steroid-treated patients had a tendency of better canal improvements (13/18, 72%) than nonsteroid-treated ones (10/18, 55.6%). However, there was no significant difference between these two groups. In cases with persistent canal paresis, steroid-treated patients (n = 5) reduced handicaps in their everyday life due to the dizziness induced by head and/or body movements and the disturbance of their mood, more effectively than those with nonsteroid therapy (n = 8). These findings suggest that steroid therapy with VN could be effective on not only vestibular periphery but central vestibular system, to restore the balance.