Impact of specialist ataxia centres on health service resource utilisation and costs across Europe: cross-sectional survey.

BACKGROUND: Little is known about the costs of treating ataxia and whether treatment at a specialist ataxia centre affects the cost of care. The aim of this study was to investigate whether patients who attended specialist ataxia centres in three European countries reported differences in their health care use and costs compared with patients who did not attend a specialist ataxia centre. We compared mean resource use and health service costs per patient affected by ataxia in the United Kingdom, Italy and Germany over a 12-month period. Data were obtained from a survey distributed to people with ataxia in the three countries. We compared mean resource use for each contact type and costs, stratifying patients by whether they were currently attending a specialist ataxia centre or had never attended one. RESULTS: Responses were received from 181 patients from the United Kingdom, 96 from Italy and 43 from Germany. Differences in the numbers of contacts for most types of health service use between the specialist ataxia centre and non-specialist ataxia centre groups were non-significant. In the United Kingdom the mean total cost per patient was €2209 for non-specialist ataxia centre patients and €1813 for specialist ataxia centre patients (P = 0.59). In Italy these figures were €2126 and €1971, respectively (P = 0.84). In Germany they were €2431 and €4087, respectively (P = 0.19). Inpatient stays made the largest contribution to total costs. CONCLUSIONS: Within each country, resource use and costs were broadly similar for specialist ataxia centre and non-specialist ataxia centre groups. There were differences between countries in terms of health care contacts and costs.

Patient pathways for rare diseases in Europe: ataxia as an example.

BACKGROUND: Progressive ataxias are rare and complex neurological disorders that represent a challenge for the clinicians to diagnose and manage them. This study explored the patient pathways of individuals attending specialist ataxia centres (SAC) compared with non-specialist settings. We investigated specifically how diagnosis was reached, the access to healthcare services, treatments, and care satisfaction. The focus of this study was on early intervention, coordination of treatment to understand the care provision in different countries. METHODS: A patient survey was done in the UK, Germany and Italy to gather information about diagnosis and management of the ataxias in specialist (SAC) and non-specialist settings, utilisation of other primary and secondary health care services, and patients' satisfaction of received treatment. RESULTS: Patients gave positive feedback about the role of SAC in understanding their condition, ways to manage their ataxia (p < 0.001; UK) and delivering care adapted to their needs (p < 0.001; UK), in coordinating referrals to other healthcare specialists, and in offering opportunities to take part in research studies. Similar barriers for patients were identified in accessing the SACs among the selected countries, UK, Germany, and Italy. CONCLUSIONS: This study provides crucial information about the ataxia patients care pathways in three European countries. Overall, the results showed a trend in patients' satisfaction being better in SAC compared to non-SAC. The outcomes can be used now for policy recommendations on how to improve treatment and care for people with these very rare and complex neurological diseases across Europe.

The attitude of patients with progressive ataxias towards clinical trials.

BACKGROUND: The development of new therapies may rely on the conduct of human experimentation as well as later clinical trials of therapeutic interventions. Ethical considerations seek to protect the patient from risk but few have sought to ascertain the attitude to such risk of patients with progressive debilitating or terminal conditions, for which no mitigating or curative therapies exist. Such understanding is also important if recruitment is to be maximized. We therefore sought to define the motivations for and barriers to trial participation amongst patients with progressive ataxias, as well as their condition-specific trial preferences. METHODS: We conducted an online survey consisting of 29 questions covering four key domains (demographics, personal motivation, drug therapy and study design) relating to the design of clinical trials. Two major ataxia charities, Ataxia UK and the Friedreich's Ataxia Research Alliance (FARA) sent the survey to their members. Responses were analysed by disease and by ambulatory status. RESULTS: Of 342 respondents, 204 reported a diagnosis of Friedreich's ataxia (FRDA), 55 inherited cerebellar ataxia (CA) and 70 idiopathic CA. The most important symptoms to be addressed by a trial were considered to be balance problems and ambulation, although these were superseded by speech problems in wheelchair users. Common motivations for participation were potential benefits to self and others. Reasons for non-participation included concerns about side effects, and the burden and cost of travel. Financial reimbursement for expenses was reported to be likely to increase trial engagement, Phase two trials were the most popular to participate in, and the use of a placebo arm was seen as a disincentive. Across all disease subgroups, drug repurposing trials proved popular and just under 70% of participants would be prepared to undergo intrathecal drug administration. CONCLUSIONS: Knowledge of motivations for and barriers to trial participation as well as the acceptability of investigations, time commitments and routes of drug administration should inform better, more patient focused trial design. This in turn may improve recruitment and retention of participants to future trials.

Diagnosis and management of progressive ataxia in adults.

Progressive ataxia in adults can be difficult to diagnose, owing to its heterogeneity and the rarity of individual causes. Many patients remain undiagnosed ('idiopathic' ataxia). This paper provides suggested diagnostic pathways for the general neurologist, based on Ataxia UK's guidelines for professionals. MR brain scanning can provide diagnostic clues, as well as identify 'structural' causes such as tumours and multiple sclerosis. Advances in molecular genetics, including the wider and cheaper availability of 'next-generation sequencing', have enabled clinicians to identify many more cases with a genetic cause. Finally, autoimmunity is probably an under-recognised cause of progressive ataxia: as well as patients with antigliadin antibodies there are smaller numbers with various antibodies, including some associated with cancer. There are a few treatable ataxias, but also symptomatic treatments to help people with the spectrum of complications that might accompany progressive ataxias. Multidisciplinary team involvement and allied health professionals' input are critical to excellent patient care, including in the palliative phase. We can no longer justify a nihilistic approach to the management of ataxia.

Guidelines on the diagnosis and management of the progressive ataxias.

The progressive ataxias are a group of rare and complicated neurological disorders, knowledge of which is often poor among healthcare professionals (HCPs). The patient support group Ataxia UK, recognising the lack of awareness of this group of conditions, has developed medical guidelines for the diagnosis and management of ataxia. Although ataxia can be a symptom of many common conditions, the focus here is on the progressive ataxias, and include hereditary ataxia (e.g. spinocerebellar ataxia (SCA), Friedreich's ataxia (FRDA)), idiopathic sporadic cerebellar ataxia, and specific neurodegenerative disorders in which ataxia is the dominant symptom (e.g. cerebellar variant of multiple systems atrophy (MSA-C)). Over 100 different disorders can lead to ataxia, so diagnosis can be challenging. Although there are no disease-modifying treatments for most of these entities, many aspects of the conditions are treatable, and their identification by HCPs is vital. The early diagnosis and management of the (currently) few reversible causes are also of paramount importance. More than 30 UK health professionals with experience in the field contributed to the guidelines, their input reflecting their respective clinical expertise in various aspects of ataxia diagnosis and management. They reviewed the published literature in their fields, and provided summaries on "best" practice, including the grading of evidence available for interventions, using the Guideline International Network (GIN) criteria, in the relevant sections.A Guideline Development Group, consisting of ataxia specialist neurologists and representatives of Ataxia UK (including patients and carers), reviewed all sections, produced recommendations with levels of evidence, and discussed modifications (where necessary) with contributors until consensus was reached. Where no specific published data existed, recommendations were based on data related to similar conditions (e.g. multiple sclerosis) and/or expert opinion. The guidelines aim to assist HCPs when caring for patients with progressive ataxia, indicate evidence-based (where it exists) and best practice, and act overall as a useful resource for clinicians involved in managing ataxic patients. They do, however, also highlight the urgent need to develop effective disease-modifying treatments, and, given the large number of recommendations based on "good practice points", emphasise the need for further research to provide evidence for effective symptomatic therapies.These guidelines are aimed predominantly at HCPs in secondary care (such as general neurologists, clinical geneticists, physiotherapists, speech and language therapists, occupational therapists, etc.) who provide care for individuals with progressive ataxia and their families, and not ataxia specialists. It is a useful, practical tool to forward to HCPs at the time referrals are made for on-going care, for example in the community.

Reduction of RPT6/S8 (a Proteasome Component) and Proteasome Activity in the Cortex is Associated with Cognitive Impairment in Lewy Body Dementia.

Lewy body dementia is the second most common neurodegenerative dementia and is pathologically characterized by α-synuclein positive cytoplasmic inclusions, with varying amounts of amyloid-ß (Aß) and hyperphosphorylated tau (tau) aggregates in addition to synaptic loss. A dysfunctional ubiquitin proteasome system (UPS), the major proteolytic pathway responsible for the clearance of short lived proteins, may be a mediating factor of disease progression and of the development of α-synuclein aggregates. In the present study, protein expression of a key component of the UPS, the RPT6 subunit of the 19S regulatory complex was determined. Furthermore, the main proteolytic-like (chymotrypsin- and PGPH-) activities have also been analyzed. The middle frontal (Brodmann, BA9), inferior parietal (BA40), and anterior cingulate (BA24) gyrus' cortex were selected as regions of interest from Parkinson's disease dementia (PDD, n = 31), dementia with Lewy bodies (DLB, n = 44), Alzheimer's disease (AD, n = 16), and control (n = 24) brains. Clinical and pathological data available included the MMSE score. DLB, PDD, and AD were characterized by significant reductions of RPT6 (one-way ANOVA, p < 0.001; Bonferroni post hoc test) in prefrontal cortex and parietal cortex compared with controls. Strong associations were observed between RPT6 levels in prefrontal, parietal cortex, and anterior cingulate gyrus and cognitive impairment (p = 0.001, p = 0.001, and p = 0.008, respectively). These findings highlight the involvement of the UPS in Lewy body dementia and indicate that targeting the UPS may have the potential to slow down or reduce the progression of cognitive impairment in DLB and PDD.

Decreased Levels of VAMP2 and Monomeric Alpha-Synuclein Correlate with Duration of Dementia.

Alpha-synuclein (α-syn) aggregations are the key pathological hallmark of dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), but are also frequently present in Alzheimer's disease (AD). Much remains unknown about the role of α-syn in the synapse and the wider role of synaptic dysfunction in these dementias. Changes in concentrations of key 'SNAP (Soluble N-ethylmaleimide Sensitive Factor Attachment Protein) Receptor' (SNARE) proteins as a consequence of alterations in the aggregation state of α-syn may contribute to synaptic dysfunction in patients with DLB, PDD, and AD and result in impaired cognition. We have studied a large cohort (n = 130) of autopsy confirmed DLB, PDD, AD, and control brains. Using semi-quantitative western blotting, we have demonstrated significant changes across the diagnostic groups of DLB, PDD, and AD in the SNARE and vesicle proteins syntaxin, Munc18, VAMP2, and monomeric α-syn in the prefrontal cortex, with a significant reduction of Munc18 in AD patients (p <  0.001). This correlated to the final MMSE score before death (p = 0.016). We also identified a significant negative correlation between the duration of dementia and the levels of the binding partners VAMP2 (p = 0.0004) and monomeric α-syn (p = 0.0002). Our findings may indicate that an upregulation of SNARE complex related proteins occurs in the early stages of disease as an attempt at compensating for failing synapses, prior to widespread deposition of pathological α-syn.

Depression and synaptic zinc regulation in Alzheimer disease, dementia with lewy bodies, and Parkinson disease dementia.

OBJECTIVE: Depression is a common symptom in dementia with Lewy bodies (DLB), Parkinson disease dementia (PDD), and Alzheimer disease (AD), yet its molecular basis remains unclear and current antidepressants do not appear to be effective. Cerebral zinc has been implicated in depression and synaptic dysfunction. We investigated the relationship between synaptic zinc regulation (for which zinc transporter 3 [ZnT3] is responsible) and depression in a large clinicopathologic study. METHODS: We examined brains from people with PDD (N = 29), DLB (N = 27), and AD (N = 15) and comparison subjects without depression or dementia (N = 24). Individuals were categorized according to the presence and severity of depression (on a scale of 0-3) based on standardized assessments during life (principally Neuropsychiatric Inventory). Western blotting was used to determine ZnT3 levels in Brodmann area 9 (BA9), and regression analysis was used to determine the relationship between ZnT3 and depression. RESULTS: Reductions in ZnT3 in BA9 were significantly associated with elevated depression scores in the study cohort (ß = -0.351, df = 93, t = -3.318 p = 0.0004). This association remained when only individuals with DLB, PDD, and no dementia or depression were examined (ß = -0.347, df = 78, t = -3.271, p = 0.002) or only individuals with AD and no dementia or depression were examined (ß = -0.433, df = 37, t = -2.924, p = 0.006). CONCLUSION: Although decreased zinc levels have been implicated in the genesis of depression in animal models and in major depressive disorder in humans, this study provides the first evidence of a role for zinc in depression in people with dementia and highlights zinc metabolism as a therapeutic target.

Assessment of ZnT3 and PSD95 protein levels in Lewy body dementias and Alzheimer's disease: association with cognitive impairment.

The loss of zinc transporter 3 (ZnT3) has been implicated in age-related cognitive decline in mice, and the protein has been associated with plaques. We investigated the levels of ZnT3 and postsynaptic density protein 95 (PSD95), a marker of the postsynaptic terminal, in people with Parkinson's disease dementia (PDD, n = 31), dementia with Lewy bodies (DLB, n = 44), Alzheimer's disease (AD, n = 16), and controls (n = 24), using semiquantitative western blotting and immunohistochemistry in 3 cortical regions. Standardized cognitive assessments during life and semiquantitative scoring of amyloid ß (Aß), tau, and α-synuclein at postmortem were used to investigate the relationship between ZnT3 and PSD95, cognition and pathology. Associations were observed between ZnT3 and PSD95 levels in prefrontal cortex and cognitive impairment (p = 0.001 and p = 0.002, respectively) and between ZnT3 levels in the parietal cortex and cognitive impairment (p = 0.036). Associations were also seen between ZnT3 levels in cingulate cortex and severity of Aß (p = 0.003) and tau (p = 0.011) pathologies. DLB and PDD were characterized by significant reductions of PSD95 (p < 0.05) and ZnT3 (p < 0.001) in prefrontal cortex compared with controls and AD. PSD95 levels in the parietal cortex were found to be decreased in AD cases compared with controls (p = 0.02) and PDD (p = 0.005). This study has identified Zn(2+) modulation as a possible novel target for the treatment of cognitive impairment in DLB and PDD and the potential for synaptic proteins to be used as a biomarker for the differentiation of DLB and PDD from AD.

Dynamin protein in stroke and vascular dementia.

Damage to sub-cortical white matter is a key substrate of vascular dementia (VaD) leading to deficits in executive function and cognitive processing speed. Dynamin1 is a 100 kDa protein, accounting for 0.4% of the total brain protein, and has a central role in many intracellular processes such as synaptic vesicle trafficking and recycling. In this study, we examined the status of Dynamin1 in the white matter from frontal cortex area. In order to measure the levels of Dynamin1, we isolated cortical white matter from a total of 34 post-mortem brains derived from controls (N=11), mixed Alzheimer's disease (AD) and VaD (N=8), VaD (N=7), and stroke no dementia (SND, N=8) subjects. A commercial ELISA kit was then used to determine the level of Dynamin1. In comparison to controls, Dynamin1 was elevated in patients SND (+400%) and reduced in patients with mixed VaD (-50%). Furthermore, levels of Dynamin1 were significantly associated with preserved cognition as indicated by the MMSE and CAMCOG and upregulation of vesicular glutamate transporter 1. This work indicates that Dynamin1 is associated with both preserved cognition and regenerative responses in older people with cerebrovascular disease and may represent a novel treatment target.

Dynamin1 concentration in the prefrontal cortex is associated with cognitive impairment in Lewy body dementia.

Dementia with Lewy Bodies (DLB) and Parkinson's Disease Dementia (PDD) together, represent the second most common cause of dementia, after Alzheimer's disease (AD). The synaptic dysfunctions underlying the cognitive decline and psychiatric symptoms observed throughout the development of PDD and DLB are still under investigation. In this study we examined the expression level of Dynamin1 and phospho-CaMKII, key proteins of endocytosis and synaptic plasticity respectively, as potential markers of molecular processes specifically deregulated with DLB and/or PDD. In order to measure the levels of these proteins, we isolated grey matter from post-mortem prefrontal cortex area (BA9), anterior cingulated gyrus (BA24) and parietal cortex (BA40) from DLB and PDD patients in comparison to age-matched controls and a group of AD cases. Clinical and pathological data available included the MMSE score, neuropsychiatric history, and semi-quantitative scores for AD pathology (plaques - tangles) and for α-synuclein (Lewy bodies). Changes in the expression of the synaptic markers, and correlates with neuropathological features and cognitive decline were predominantly found in the prefrontal cortex. On one hand, levels of Dynamin1 were significantly reduced, and correlated with a higher rate of cognitive decline observed in cases from three dementia groups. On the other hand, the fraction of phospho-CaMKII was decreased, and correlated with a high score of plaques and tangles in BA9. Interestingly, the correlation between the rate of cognitive decline and the level of Dynamin1 remained when the analysis was restricted to the PDD and DLB cases, highlighting an association of Dynamin1 with cognitive decline in people with Lewy Body dementia.

Methylglyoxal evokes pain by stimulating TRPA1.

Diabetic neuropathy is a severe complication of long-standing diabetes and one of the major etiologies of neuropathic pain. Diabetes is associated with an increased formation of reactive oxygen species and the electrophilic dicarbonyl compound methylglyoxal (MG). Here we show that MG stimulates heterologously expressed TRPA1 in CHO cells and natively expressed TRPA1 in MDCK cells and DRG neurons. MG evokes [Ca(2+)]i-responses in TRPA1 expressing DRG neurons but is without effect in neurons cultured from Trpa1(-/-) mice. Consistent with a direct, intracellular action, we show that methylglyoxal is significantly more potent as a TRPA1 agonist when applied to the intracellular face of excised membrane patches than to intact cells. Local intraplantar administration of MG evokes a pain response in Trpa1(+/+) but not in Trpa1(-/-) mice. Furthermore, persistently increased MG levels achieved by two weeks pharmacological inhibition of glyoxalase-1 (GLO-1), the rate-limiting enzyme responsible for detoxification of MG, evokes a progressive and marked thermal (cold and heat) and mechanical hypersensitivity in wildtype but not in Trpa1(-/-) mice. Our results thus demonstrate that TRPA1 is required both for the acute pain response evoked by topical MG and for the long-lasting pronociceptive effects associated with elevated MG in vivo. In contrast to our observations in DRG neurons, MG evokes indistinguishable [Ca(2+)]i-responses in pancreatic ß-cells cultured from Trpa1(+/+) and Trpa1(-/-) mice. In vivo, the TRPA1 antagonist HC030031 impairs glucose clearance in the glucose tolerance test both in Trpa1(+/+) and Trpa1(-/-) mice, indicating a non-TRPA1 mediated effect and suggesting that results obtained with this compound should be interpreted with caution. Our results show that TRPA1 is the principal target for MG in sensory neurons but not in pancreatic ß-cells and that activation of TRPA1 by MG produces a painful neuropathy with the behavioral hallmarks of diabetic neuropathy.

Kinetic activation of yeast mitochondrial D-lactate dehydrogenase by carboxylic acids.

Aerobically grown yeast cells express mitochondrial lactate dehydrogenases that localize to the mitochondrial inner membrane. The D-lactate dehydrogenase is a zinc-flavoprotein with high acceptor specificity for cytochrome c, that catalyzes the oxidation of D-lactate into pyruvate. In this paper, we show that mitochondrial respiratory rate in phosphorylating or non-phosphorylating conditions with D-lactate as substrate is stimulated by carboxylic acids. This stimulation does not affect the yield of oxidative phosphorylation. Furthermore, this stimulation lies at the level of the D-lactate dehydrogenase. It is non-competitive, hyperbolic and its dimension is directly related to the number of carboxylic groups on the activator. The physiological meaning of such a regulation is discussed.

T3 administration in adult hypothyroid mice modulates expression of proteins involved in striatal synaptic plasticity and improves motor behavior.

Adult-onset hypothyroidism is associated with neurological changes such as cognitive dysfunction and impaired learning, which may be related to alterations of synaptic plasticity. We investigate the consequence of adult-onset hypothyroidism on thyroid-mediated transcription events in striatal synaptic plasticity, and the effect of triiodothyronine (T3) replacement. We used hypothyroid mice, treated with propylthiouracil (PTU) and methimazole (MMI), with or without subsequent administration of T3. We evaluated the amount of T3 nuclear receptors (TRalpha1, TRbeta) and striatal plasticity indicators: neurogranin (RC3), Ras homolog enriched in striatum (Rhes), Ca2+/calmodulin-dependent protein kinase (CaMKII), and dopamine- and cAMP-regulated phosphoprotein (DARPP-32). In addition, we assessed hypothyroid mice motor behavior as related to striatum synaptic functions. Hypothyroid mice exhibited significantly reduced TRbeta, RC3 and Rhes expression. T3 administration reversed the expression of TRbeta, RC3, and up-regulated CaMKII levels as well as motor behavior, and decreased DARPP-32 protein phosphorylation. We suggest that thyroid hormone modulation had a major impact on striatal synaptic plasticity of adult mice which produced in turn motor behavior modifications.

The yeast cAMP protein kinase Tpk3p is involved in the regulation of mitochondrial enzymatic content during growth.

During aerobic cell growth, mitochondria must meet energy demand either by adjusting cellular mitochondrial content or by adjusting ATP production flux, allowing a constant growth yield. On respiratory substrate, the Ras/cAMP pathway has been shown to be involved in this process in the yeast Saccharomyces cerevisiae. We show that of the three cAMP protein kinase catalytic subunits, Tpk3p is the one specifically involved in the regulation of cellular mitochondrial content when energy demand decreases. In decreased energy demand, the Deltatpk3 mitochondrial enzymatic content decreases leading to a subsequent decrease in the cellular growth rate. Moreover, enzymatic content decreases in the Deltatpk3 isolated mitochondria, suggesting that the amount of cellular mitochondria is not affected, but rather that the mitochondria are modified. Our study points to an important decrease in the cytochrome c content in the Deltatpk3 mitochondria, which leads to a decrease in the slipping process at the level of cytochrome-c-oxidase.