Treatment experience, burden, and unmet needs (TRIBUNE) in Multiple Sclerosis study: the costs and utilities of MS patients in The Netherlands.

BACKGROUND: Multiple sclerosis (MS) is an important, highly disabling neurological disease, common among young adults in The Netherlands. Nevertheless, only a few studies to date have measured the burden imposed by MS on society in The Netherlands. OBJECTIVES: To estimate the cost and quality-of-life associated with MS in The Netherlands, while focusing on the burden of relapses and increasing disease severity. METHODS: MS patients in The Netherlands (n = 263) completed a web-based questionnaire which captured information on demographics, disease characteristics and severity (Expanded Disability Status Scale [EDSS]), co-morbidities, relapses, resource consumption, utilities, fatigue and activities of daily living (ADL). RESULTS: Most patients included in the study were receiving treatment for MS (76% of the sample). The mean cost per patient per year increased with worsening disability and was estimated at €30,938, €51,056, and €100,469 for patients with mild (EDSS 0-3), moderate (EDSS 4-6.5), and severe (EDSS 7-9) disability, respectively. The excess cost of relapses was estimated at €8195 among relapsing-remitting patients with EDSS score ≤5. The quality-of-life of patients decreased with disease progression and existence of relapses. CONCLUSIONS: The cost of MS in The Netherlands was higher compared to the results of previous studies. The TRIBUNE study provides an important update on the economic burden of MS in The Netherlands in an era of more widespread use of disease-modifying therapies. It explores the cost of MS linked to relapses and disease severity and examines the impact of MS on additional health outcomes beyond utilities such as ADL and fatigue. STUDY LIMITATIONS: Patients were selected from specialized treatment centers, therefore this sample may not be representative of the entire MS population in The Netherlands, i.e., few patients not receiving MS therapies were included. In addition, only a few patients with severe disability were included in the study sample; therefore, results for this disease severity sub-group should be interpreted with caution.

Fingolimod reduces direct medical costs compared to natalizumab in patients with relapsing-remitting multiple sclerosis in The Netherlands.

OBJECTIVE: To assess the costs of oral treatment with Gilenya® (fingolimod) compared to intravenous infusion of Tysabri® (natalizumab) in patients with relapsing-remitting multiple sclerosis (RRMS) in The Netherlands. METHODS: A cost-minimization analysis was used to compare both treatments. The following cost categories were distinguished: drug acquisition costs, administration costs, and monitoring costs. Costs were discounted at 4%, and incremental model results were presented over a 1, 2, 5, and 10 year time horizon. The robustness of the results was determined by means of a number of deterministic univariate sensitivity analyses. Additionally, a break-even analysis was carried out to determine at which natalizumab infusion costs a cost-neutral outcome would be obtained. RESULTS: Comparing fingolimod to natalizumab, the model predicted discounted incremental costs of -€2966 (95% CI: -€4209; -€1801), -€6240 (95% CI: -€8800; -€3879), -€15,328 (95% CI: -€21,539; -€9692), and -€28,287 (95% CI: -€39,661; -€17,955) over a 1, 2, 5, and 10-year time horizon, respectively. These predictions were most sensitive to changes in the costs of natalizumab infusion. Changing these costs of €255 within a range from €165-364 per infusion resulted in cost savings varying from €4031 to €8923 after 2 years. The additional break-even analysis showed that infusion costs-including aseptic preparation of the natalizumab solution-needed to be as low as the respective costs of €94 and €80 to obtain a cost neutral result after 2 and 10 years. LIMITATIONS: Neither treatment discontinuation and subsequent re-initiation nor patient compliance were taken into account. As a consequence of the applied cost-minimization technique, only direct medical costs were included. CONCLUSION: The present analysis showed that treatment with fingolimod resulted in considerable cost savings compared to natalizumab: starting at €2966 in the first year, increasing to a total of €28,287 after 10 years per RRMS patient in the Netherlands.

Haploinsufficiency of glutamine synthetase increases susceptibility to experimental febrile seizures.

Glutamine synthetase (GS) is a pivotal glial enzyme in the glutamate-glutamine cycle. GS is important in maintaining low extracellular glutamate concentrations and is downregulated in the hippocampus of temporal lobe epilepsy patients with mesial-temporal sclerosis, an epilepsy syndrome that is frequently associated with early life febrile seizures (FS). Human congenital loss of GS activity has been shown to result in brain malformations, seizures and death within days after birth. Recently, we showed that GS knockout mice die during embryonic development and that haploinsufficient GS mice have no obvious abnormalities or behavioral seizures. In the present study, we investigated whether reduced expression/activity of GS in haploinsufficient GS mice increased the susceptibility to experimentally induced FS. FS were elicited by warm-air-induced hyperthermia in 14-day-old mice and resulted in seizures in most animals. FS susceptibility was measured as latencies to four behavioral FS characteristics. Our phenotypic data show that haploinsufficient mice are more susceptible to experimentally induced FS (P < 0.005) than littermate controls. Haploinsufficient animals did not differ from controls in hippocampal amino acid content, structure (Nissl and calbindin), glial properties (glial fibrillary acidic protein and vimentin) or expression of other components of the glutamate-glutamine cycle (excitatory amino acid transporter-2 and vesicular glutamate transporter-1). Thus, we identified GS as a FS susceptibility gene. GS activity-disrupting mutations have been described in the human population, but heterozygote mutations were not clearly associated with seizures or epilepsy. Our results indicate that individuals with reduced GS activity may have reduced FS seizure thresholds. Genetic association studies will be required to test this hypothesis.

Reduced glutamine synthetase in hippocampal areas with neuron loss in temporal lobe epilepsy.

BACKGROUND: Increased levels of glutamate have been reported in the epileptogenic hippocampus of patients with temporal lobe epilepsy (TLE). This sustained increase, which may contribute to the initiation and propagation of seizure activity, indicates impaired clearance of glutamate released by neurons. Glutamate is predominantly cleared by glial cells through the excitatory amino acid transporter 2 (EAAT2) and its subsequent conversion to glutamine by the glial enzyme glutamine synthetase (GS). METHODS: The authors examined the hippocampal distribution of GS, EAAT2, and glial fibrillary acidic protein (GFAP) by immunohistochemistry in TLE patients with (HS group) and without hippocampal sclerosis (non-HS group), and in autopsy controls. In hippocampal homogenates the authors measured relative protein amounts by immunoblotting and GS enzyme activity. RESULTS: In the autopsy control and non-HS group GS immunoreactivity (IR) was predominantly found in glia in the neuropil of the subiculum, of the pyramidal cell layer of all CA fields, and in the supragranular layer of the dentate gyrus. In the HS group, GS and EAAT2 IR were markedly reduced in subfields showing neuron loss (CA1 and CA4), whereas GFAP IR was increased. The reduction in GS IR in the HS group was confirmed by immunoblotting and paralleled by decreased GS enzyme activity. CONCLUSIONS: Glial glutamine synthetase is downregulated in the hippocampal sclerosis (HS) hippocampus of temporal lobe epilepsy (TLE) patients in areas with severe neuron loss. This downregulation appears to be pathology-related, rather than seizure-related, and may be part of the mechanism underlying impaired glutamate clearance found in the hippocampus of TLE patients with HS.

Suppression of cortical spreading depressions after magnesium treatment in the rat.

The aim of this study was to investigate whether the neuroprotective properties of magnesium in cerebral ischaemia involve suppression of repetitive tissue depolarizations. Cortical spreading depressions (CSDs), evoked by cortical KCl application, and cardiac arrest-induced anoxic depolarization (AD) were measured by extracellular DC recording on intact rat brain. At 90 min after onset of CSDs saline, MK-801 (3 mg/kg) or MgSO4 (90 mg/kg) was given i.v. Latency time to AD was measured after 4 h. The frequency of CSDs was significantly reduced in animals treated with MgSO4 or MK-801. AD was significantly delayed by MgSO4 but not by MK-801. Our results suggest that suppression of depolarization by magnesium may play a role in its neuroprotective properties in cerebral ischaemia.