Retraction Note to: Menière's disease: combined pharmacotherapy with betahistine and the MAO-B inhibitor selegiline-an observational study.

The authors have retracted this article.

Influence of interferon-beta therapy switching on neutralizing antibody titres: results from the Austrian Switch Study.

Neutralizing antibodies against interferon-beta are associated with a reduction of the efficacy of this drug. Continuing treatment leads to a decline or even loss of neutralizing antibodies over years. No strategies are currently available to shorten the period of neutralizing antibody positivity. The objective of this study was to investigate the effect of switching between high and low immunogenic interferon-beta products on neutralising antibody titres. Twenty-four patients treated with the subcutaneously administered interferon-beta 1b or 1a and high titres of neutralizing antibodies were included. At baseline interferon-beta therapy was interrupted for 3 months and two pulses of high dose methylprednisolone were applied. Patients were then randomized to receive either the previous interferon-beta preparation or the low immunogenic intramuscular interferon-beta 1a. The primary end-point was the change of neutralizing antibody titres 12 months after randomization. Twelve patients were switched to interferon-beta 1a intramuscularly and 12 patients remained on previous treatment. Median neutralizing antibody titres were 846 NU at baseline and 196 NU at the end of the study. The median change of neutralizing antibody titres did not differ significantly between therapy switchers and non-switchers. Baseline and final neutralizing antibody titres correlated significantly. In conclusion, neither switching nor continuous therapy with any subcutaneous interferon-beta preparation significantly changed neutralizing antibody titres.

Menière's disease: combined pharmacotherapy with betahistine and the MAO-B inhibitor selegiline-an observational study.

OBJECTIVES: Since oral betahistine has a very high first-pass effect (ca. 99%), metabolized by monoamine oxidases (MAO), the benefits of a high-dosage betahistine monotherapy were compared with those of a lower dosage of betahistine in combination with the MAO-B inhibitor (MAO-B) selegiline on the frequency of acute attacks of vertigo in patients with Menière's disease (MD). METHODS: Thirteen adults aged 40-75 years (mean 58.9 years; six females) had initially been treated with a high dosage of betahistine dihydrochloride for at least 1 year. Under this therapy, all of them had ≤ 1 attack for ≥ 3 months prior to the combination pharmacotherapy. Subsequently, they received 5 mg/day selegiline and the dosage of betahistine was reduced to about one tenth and then individually adjusted to the dosage needed to achieve the same treatment response (≤ 1 per 3 months, observational period of at least 6 months). RESULTS: The initial dosage for the long-term "titration" of the attacks of vertigo was 9-80 24-mg tablets/day (mean 37.3), i.e. 216-1920 mg/day (mean 895.4 mg/day). After the combination with selegiline, the dosage needed to achieve the same benefit for ≥ 3 months was 3-36 24-mg tablets (mean 8.5), i.e., 72-864 mg/day [mean 204.9 mg/day, p < 0.001 (paired t test)]. One patient transiently stopped the treatment with selegiline, another one reduced the dosage to 2.5 mg/day and the attacks re-occurred after 2-4 weeks. Six out of 13 patients reported transient fullness of the head during the combined treatment; in 2 of them this went away when they switched to 2.5 mg bid. In the longer term (> 9 months), one patient had to increase the selegiline dosage to 5 mg bd, one patient stopped the treatment with selegiline. CONCLUSIONS: The achievement of the same clinical effect with a significantly lower (about 1/5) dosage of betahistine can be explained by the inhibition of the MAO-B by selegiline leading to higher serum concentrations of betahistine. This approach is in line with recent developments to bypass the first-pass effect of betahistine by transbuccal or intranasal application. Despite the substantial methodological limitations of such an observational study, this combined pharmacotherapy could be an alternative to a high-dosage monotherapy with betahistine of MD.

Antimyelin antibodies as a predictor of clinically definite multiple sclerosis after a first demyelinating event.

BACKGROUND: Most patients with multiple sclerosis initially present with a clinically isolated syndrome. Despite the fact that clinically definite multiple sclerosis will develop in up to 80 percent of these patients, the course of the disease is unpredictable at its onset and requires long-term observation or repeated magnetic resonance imaging (MRI). We investigated whether the presence of serum antibodies against myelin oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP) in patients with a clinically isolated syndrome predicts the interval to conversion to clinically definite multiple sclerosis. METHODS: A total of 103 patients with a clinically isolated syndrome, positive findings on cerebral MRI, and oligoclonal bands in the cerebrospinal fluid were studied. At base line, serum samples were collected to test for anti-MOG and anti-MBP antibodies with Western blot analysis, and the lesions detected by cerebral MRI were quantified. Neurologic examinations for relapse or disease progression (defined as conversion to clinically definite multiple sclerosis) were performed at base line and subsequently every three months. RESULTS: Patients with anti-MOG and anti-MBP antibodies had relapses more often and earlier than patients without these antibodies. Only 9 of 39 antibody-seronegative patients (23 percent) had a relapse, and the mean (+/-SD) time to relapse was 45.1+/-13.7 months. In contrast, 21 of 22 patients (95 percent) with antibodies against both MOG and MBP had a relapse within a mean of 7.5+/-4.4 months, and 35 of 42 patients (83 percent) with only anti-MOG antibodies had a relapse within 14.6+/-9.6 months (P<0.001 for both comparisons with antibody-seronegative patients). The adjusted hazard ratio for the development of clinically definite multiple sclerosis was 76.5 (95 percent confidence interval, 20.6 to 284.6) among the patients who were seropositive for both antibodies and 31.6 (95 percent confidence interval, 9.5 to 104.5) among the patients who were seropositive only for anti-MOG antibodies, as compared with the seronegative patients. CONCLUSIONS: Analysis of antibodies against MOG and MBP in patients with a clinically isolated syndrome is a rapid, inexpensive, and precise method for the prediction of early conversion to clinically definite multiple sclerosis. This finding may be important for the counseling and care of patients with a first demyelinating event suggestive of multiple sclerosis.

Vestibular loss causes hippocampal atrophy and impaired spatial memory in humans.

The human hippocampal formation plays a crucial role in various aspects of memory processing. Most literature on the human hippocampus stresses its non-spatial memory functions, but older work in rodents and some other species emphasized the role of the hippocampus in spatial learning and memory as well. A few human studies also point to a direct relation between hippocampal size, navigation and spatial memory. Conversely, the importance of the vestibular system for navigation and spatial memory was until now convincingly demonstrated only in animals. Using magnetic resonance imaging volumetry, we found that patients (n = 10) with acquired chronic bilateral vestibular loss (BVL) develop a significant selective atrophy of the hippocampus (16.9% decrease relative to controls). When tested with a virtual variant (on a PC) of the Morris water task these patients exhibited significant spatial memory and navigation deficits that closely matched the pattern of hippocampal atrophy. These spatial memory deficits were not associated with general memory deficits. The current data on BVL patients and bilateral hippocampal atrophy revive the idea that a major--and probably phylogenetically ancient--function of the archicortical hippocampal tissue is still evident in spatial aspects of memory processing for navigation. Furthermore, these data demonstrate for the first time in humans that spatial navigation critically depends on preserved vestibular function, even when the subjects are stationary, e.g. without any actual vestibular or somatosensory stimulation.

Cytokine profiles show heterogeneity of interferon-ß response in multiple sclerosis patients.

OBJECTIVE: To evaluate serum cytokine profiles for their utility to determine the heterogeneous responses to interferon (IFN)-ß treatment in patients with multiple sclerosis (MS). METHODS: Patients with relapsing-remitting MS (RRMS) or clinically isolated syndrome receiving de novo IFN-ß treatment were included in this prospective, observational study. Number of relapses and changes in disability were assessed 2 years prior to and 2 years after initiation of treatment. Sera were collected at baseline and after 3 months on therapy. Cytokine levels in sera were assessed by Luminex multiplex assays. Baseline cytokine profiles were grouped by hierarchical clustering analysis. Demographic features, changes in cytokines, and clinical outcome were then assessed in the clustered patient groups. RESULTS: A total of 157 patients were included in the study and clustered into 6 distinct subsets by baseline cytokine profiles. These subsets differed significantly in their clinical and biological response to IFN-ß therapy. Two subsets were associated with patients who responded poorly to therapy. Two other subsets, associated with a good response to therapy, showed a significant reduction in relapse rates and no worsening of disability. Each subset also had differential changes in cytokine levels after 3 months of IFN-ß treatment. CONCLUSIONS: There is heterogeneity in the immunologic pathways of the RRMS population, which correlates with IFN-ß response.

Spatial memory deficits in patients with chronic bilateral vestibular failure.

The role of the vestibular system for navigation and spatial memory has been demonstrated in animals but not in humans. Vestibular signals are necessary for location-specific "place cell" activity in the hippocampus which provides a putative neural substrate for the spatial representation involved in navigation. To investigate the spatial memory in patients with bilateral vestibular failure due to NF2 with bilateral neurectomy, a virtual variant (on a PC) of the Morris water task adapted to humans was used. Significant spatial learning and memory deficits were shown in 12 patients as compared to 10 healthy controls. These data suggest that functional hippocampal deficits manifest due to a chronic lack of vestibular input in these patients. These deficits can even be demonstrated with the subjects stationary, i.e., without any actual vestibular or somatosensory stimulation.