Background: Parkinson's disease (PD) is a chronic disease that presents a multitude of symptoms, with symptoms of both motor and nonmotor nature. The Delphi method is widely used to create consensuses among experts in a field of knowledge. Objective: In order to reach a consensus on the values that should be assigned to the different motor and nonmotor manifestations of Parkinson's disease, a linear evaluation index (LEI) was created. Subsequently, the metric properties of this index were studied. Methods: 120 consecutive patients with a Parkinson's diagnosis were chosen in accordance with the UKPDSBB criteria. The Delphi method was used to reach a consensus among experts regarding the values of each of the manifestations included. Subsequently, the following attributes were analyzed: quality and acceptability of the data; reliability, in terms of internal consistency, reliability index, Cronbach's alpha and standard error of measurement; and validity, in terms of convergent validity and validity for known groups. Results: Twenty-five experts participated. The importance factor did not differ between the first round and the second round (chi-square test). We analyzed the responses that assigned percentage values to the 10 dimensions of the LEI. Both in the first and in the second round, the values of the scattering coefficient Vr were always close to 0. The homogeneity index was 0.36; the corrected-item total correlation values ranged from 0.02 to 0.7; Cronbach's alpha was 0.69; and the SEM was 4.23 (55.1%). Conclusions: The LEI was obtained through rigorous recommended methodology. The results showed adequate metric properties.

Background: Multiple system atrophy (MSA) is a neurodegenerative condition characterized by variable combinations of parkinsonism, autonomic failure, cerebellar ataxia and pyramidal features. Although the distribution of synucleinopathy correlates with the predominant clinical features, the burden of pathology does not fully explain observed differences in clinical presentation and rate of disease progression. We hypothesized that the clinical heterogeneity in MSA is a consequence of variability in the seeding activity of alpha-synuclein both between different patients and between different brain regions. Methods: The reliable detection of alpha-synuclein seeding activity derived from MSA using cell-free amplification assays remains challenging. Therefore, we conducted a systematic evaluation of 168 different reaction buffers, using an array of pH and salts, seeded with fully characterized brain homogenates from one MSA and one PD patient. We then validated the two conditions that conferred the optimal ability to discriminate between PD- and MSA-derived samples in a larger cohort of 40 neuropathologically confirmed cases, including 15 MSA. Finally, in a subset of brains, we conducted the first multi-region analysis of seeding behaviour in MSA. Results: Using our novel buffer conditions, we show that the physicochemical factors that govern the in vitro amplification of alpha-synuclein can be tailored to generate strain-specific reaction buffers that can be used to reliably study the seeding capacity from MSA-derived alpha-synuclein. Using this novel approach, we were able to sub-categorize the 15 MSA brains into 3 groups: high, intermediate and low seeders. To further demonstrate heterogeneity in alpha-synuclein seeding in MSA, we conducted a comprehensive multi-regional evaluation of alpha-synuclein seeding in 13 different regions from 2 high seeders, 2 intermediate seeders and 2 low seeders. Conclusions: We have identified unexpected differences in seed-competent alpha-synuclein across a cohort of neuropathologically comparable MSA brains. Furthermore, our work has revealed a substantial heterogeneity in seeding activity, driven by the PBS-soluble alpha-synuclein, between different brain regions of a given individual that goes beyond immunohistochemical observations. Our observations pave the way for future subclassification of MSA, which exceeds conventional clinical and neuropathological phenotyping and considers the structural and biochemical heterogeneity of alpha-synuclein present. Finally, our methods provide an experimental framework for the development of vitally needed, rapid and sensitive diagnostic assays for MSA.

Background and objective: Parkinson's disease (PD) is a clinically heterogeneous disorder in which the symptoms and prognosis can be very different among patients. We propose a new simple classification to identify key symptoms and staging in PD. Patients and Methods: Sixteen movement disorders specialists from Spain participated in this project. The classification was consensually approved after a discussion and review process from June to October 2021. The TNM classification and the National Institutes of Health Stroke Scale (NIHSS) were considered as models in the design. Results: The classification was named MNCD and included 4 major axes: (1) motor symptoms; (2) non-motor symptoms; (3) cognition; (4) dependency for activities of daily living (ADL). Motor axis included 4 sub-axes: (1) motor fluctuations; (2) dyskinesia; (3) axial symptoms; (4) tremor. Four other sub-axes were included in the non-motor axis: (1) neuropsychiatric symptoms; (2) autonomic dysfunction; (3) sleep disturbances and fatigue; (4) pain and sensory disorders. According to the MNCD, 5 stages were considered, from stage 1 (no disabling motor or non-motor symptoms with normal cognition and independency for ADL) to 5 (dementia and dependency for basic ADL). Conclusions: A new simple classification of PD is proposed. The MNCD classification includes 4 major axes and 5 stages to identify key symptoms and monitor the evolution of the disease in patients with PD. It is necessary to apply this proof of concept in a properly designed study.

Background: Both cerebral vascular disorders and cognitive decline increase in incidence with age. The role of cerebral vascular disease and hemodynamic changes in the development of cognitive deficits is controversial. The objective of this study was to assess the cardiovascular response during cardiac stress testing in neurologically asymptomatic individuals who developed cognitive impairment several years after previous cardiac stress testing. (2) Methods: This was a retrospective cohort study of patients who underwent cardiac stress testing between January 2001 and December 2010. Patients were followed up until May 2015, and we selected those who developed cognitive dysfunction including dementia, mild cognitive impairment, and subjective cognitive decline, after the stress test. Heart rate and blood pressure both at rest and at peak exercise, and the mean R-R interval at rest were recorded. For each patient who developed cognitive impairment, we selected one matched control who did not show cognitive decline by the end of the follow-up period. (3) Results: From the cohort of 7224 patients, 371 developed cognitive impairment; of these, 186 (124 men) met the inclusion criteria, and 186 of the other patients were selected as matched controls. During follow-up, cognitive impairment appeared 6.2 +/- 4.7 years after the cardiac stress test. These patients who had subsequently developed cognitive impairment had significantly lower at-rest systolic, diastolic, and mean blood...

Background Recently, amylin and its receptors were found in different structures involved in migraine pathophysiology. Here, we evaluate interictal concentrations of amylin and calcitonin gene-related peptide in peripheral blood as biomarkers for chronic migraine. Methods We prospectively recruited patients with episodic migraine, chronic migraine and healthy controls. Interictal amylin and calcitonin gene-related peptide levels were assessed in blood samples using enzyme linked immunosorbent assay. Results We assessed plasma samples from 58 patients with episodic migraine (mean age 37.71 +/- 10.47, 87.9% female), 191 with chronic migraine (mean age 46.03 +/- 11.93, 95% female), and on 68 healthy controls (mean age 43.58 +/- 11.08 years, 86% female). Body mass index was 25.94 +/- 4.53 kg/m(2) for migraine patients and 25.13 +/- 4.92 kg/m(2) for healthy controls (p = 0.0683). Interictal plasma amylin levels were higher in chronic migraine patients (47.1 pg/mL) than in the episodic migraine patients (28.84 pg/mL, p < 0.0001) and healthy controls (24.74 pg/mL, p < 0.0001). Plasma calcitonin gene-related peptide levels were increased (20.01 pg/mL) in chronic migraine patients when compared to healthy controls (11.37 pg/mL, p = 0.0016), but not to episodic migraine patients (18.89 pg/mL, p = 0.4369). Applying a cut-off concentration of 39.68 pg/mL plasma amylin, the sensitivity to differentiate chronic migraine from healthy controls was 57.6% and the specificity was 88.2%. Variables such as age, analgesic overuse, depression, allodynia, use of preventive medication or a history of aura did not influence the plasma concentrations of amylin or calcitonin gene-related peptide. Conclusion Interictal plasma amylin levels are higher in patients with chronic migraine and may serve as a diagnostic biomarker for chronic migraine.

The olfactory bulb (OB) seems to be the first affected structure in neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and Lewy body dementia (LBD). Deposits of protein aggregates, increased dopaminergic neurons, and decreased cholinergic inputs have all been described in the OB of these diseases. We investigated here the contribution of the activated microglial cells to the increased deposits of protein aggregates. We quantified the number of activated microglial cells and astrocytes in the OB of patients with histological diagnosis of PD (n= 5), AD (n= 13), and LBD (n= 7) and aged-matched controls (n= 8). Specific consensus diagnostic criteria were applied for AD, LBD, and PD. Protein aggregates were scored in the OB as grade 0, none; grade 1, mild; grade 2, moderate; and grade 3, severe. OB sections from the 33 subjects were stained with specific antibodies markers for reactive astrocytes (GFAP) and microglial cells (Iba1 and HLA-DR). The total number of Iba1-ir (Iba-immunoreactive) and HLAD-DR cells was estimated by stereological analysis, while quantification of astrocytes was performed by GFAP optical density. Statistical analysis was done using the Stata 12.0 software. The number of microglia and activated microglia cells (HLA-RD-ir) was increased in patients with neurodegenerative diseases (p< 0.05). Moreover, the density of GFAP-ir cells was higher in the OB of patients. Neither the number of microglia cells nor the density of astrocytes correlated with the number of b-amyloid and alpha-synuclein deposits, but the density of Iba1-ir cells correlated with the number of p-Tau aggregates. Activated microglial cells and reactive astrocytes are present in the OB of patients with neurodegenerative diseases. The lack of correlation between the number of activated microglia cells and protein deposits indicate that they might independently contribute to the degenerative process. The presence of microglia is related to phosphorylated Tau deposits in neurodegenerative diseases.

Protein misfolding diseases refer to a variety of disorders that develop as a consequence of the misfolding of proteins in various organs. The etiologies of Parkinson's and Alzheimer's disease remain unclear, but it seems that type two diabetes and other prediabetic states could contribute to the appearance of the sporadic forms of these diseases. In addition to amylin deposition, other amyloidogenic proteins implicated in the pathophysiology of neurodegenerative diseases could have important roles in the pathogenesis of this disease. As we have previously demonstrated the presence of alpha-synuclein deposits in the pancreas of patients with synucleinopathies, as well as tau and A beta deposits in the pancreatic tissue of Alzheimer's disease patients, we studied the immunoreactivity of amylin, tau and alpha-synuclein in the pancreas of 138 subjects with neurodegenerative diseases or type two diabetes and assessed whether the pancreatic beta-cells of these subjects present cooccurrence of misfolded proteins. Furthermore, we also assessed the pancreatic expression of prion protein (PrP) in these subjects and its interaction, both in the pancreas and brain, with alpha-synuclein, tau, A beta and amylin. Our study shows, for the first time, that along with amylin, pancreatic alpha-synuclein, A beta, PrP and tau may contribute together to the complex pathophysiology of type two diabetes and in the appearance of insulin resistance in Alzheimer's and Parkinson's disease. Furthermore, we show that the same mixed pathologies that are observed in the brains of patients with neurodegenerative diseases are also present outside the nervous system. Finally, we provide the first histological evidence of an interaction between PrP and A beta, alpha-synuclein, amylin or tau in the pancreas and locus coeruleus. These findings will shed more light on the common pathological pathways shared by neurodegenerative diseases and type two diabetes, benefiting the exploration of common therapeutic strategies to prevent or treat these devastating amyloid diseases.

Parkinson's disease (PD) is a chronic progressive and irreversible disease and the second most common neurodegenerative disease worldwide. In Spain, it affects around 120.000-150.000 individuals, and its prevalence is estimated to increase in the future. PD has a great impact on patients' and caregivers' lives and also entails a substantial socioeconomic burden. The aim of the present study was to examine the current situation and the 10-year PD forecast for Spain in order to optimize and design future management strategies. This study was performed using the modified Delphi method to try to obtain a consensus among a panel of movement disorders experts. According to the panel, future PD management will improve diagnostic capacity and follow-up, it will include multidisciplinary teams, and innovative treatments will be developed. The expansion of new technologies and studies on biomarkers will have an impact on future PD management, leading to more accurate diagnoses, prognoses, and individualized therapies. However, the socio-economic impact of the disease will continue to be significant by 2030, especially for patients in advanced stages. This study highlighted the unmet needs in diagnosis and treatment and how crucial it is to establish recommendations for future diagnostic and therapeutic management of PD.

Background: Advanced Parkinson's disease (APD) has been recently defined as a stage in which certain symptoms and complications are present, with a detrimental influence on the overall patient's health conditions and with a poor response to conventional treatments. However, historically, the term APD has been controversial, thus consequently, APD prevalence has not been previously studied. Objectives: The main objective was to determine the prevalence of APD in patients diagnosed with idiopathic PD in hospitals of the Spanish National Healthcare System. Secondary objectives were the prevalence and incidence of PD and the clinical and sociodemographic characteristics and quality of life of patients with APD or non-APD. Methods: This was a non-interventional, cross-sectional, multicenter, national study in the hospital setting. Results: The study population included 929 patients with PD (mean age 71.8 +/- 10.1 years; 53.8% male) and a mean time since diagnosis of 6.6 +/- 5.4 years. At the time of diagnosis, 613 patients (66.06%) reported having had premotor symptoms. The Hoehn and Yahr stage was 1 in 15.7% of the patients, 2 in 42.8%, 3 in 30.1%, 4 in 9.9%, and 5 in 1.4%; 46.9% of the patients had comorbidities (mean age-adjusted Charlson comorbidity index 3.5 +/- 1.7; median 10-year survival 77%) and the mean 8-item Parkinson's Disease Quality of Life Questionnaire was 27.8 +/- 20.5. We found an APD prevalence of 38.21% (95%CI: 35.08-41.42%), a PD prevalence of 118.4 (95%CI: 117.3-119.6), and a PD incidence of 9.4 (95%CI: 5.42-13.4) all per 100,000 population. Among the APD population, a 15.2% were receiving some form of therapy for advanced stages of the disease (deep brain stimulation, levodopa/carbidopa intestinal gel, or apomorphine subcutaneous infusion). Conclusions: The percentage of patients with APD in the hospitals of the Spanish National Healthcare System was 38.2%.