Frequency and phenotypic spectrum of spinocerebellar ataxia 27B and other genetic ataxias in a Spanish cohort of late-onset cerebellar ataxia

BACKGROUND AND PURPOSE

Dominantly inherited GAA repeat expansions in the fibroblast growth factor 14 (FGF14) gene have recently been shown to cause spinocerebellar ataxia 27B (SCA27B). We aimed to study the frequency and phenotype of SCA27B in a cohort of patients with unsolved late-onset cerebellar ataxia (LOCA). We also assessed the frequency of SCA27B relative to other genetically defined LOCAs.

METHODS

We recruited a consecutive series of 107 patients with LOCA, of whom 64 remained genetically undiagnosed. We screened these 64 patients for the FGF14 GAA repeat expansion. We next analysed the frequency of SCA27B relative to other genetically defined forms of LOCA in the cohort of 107 patients.

RESULTS

Eighteen of 64 patients (28%) carried an FGF14 (GAA)≥250 expansion. The median (range) age at onset was 62.5 (39-72) years. The most common clinical features included gait ataxia (100%) and mild cerebellar dysarthria (67%). In addition, episodic symptoms and downbeat nystagmus were present in 39% (7/18) and 37% (6/16) of patients, respectively. SCA27B was the most common cause of LOCA in our cohort (17%, 18/107). Among patients with genetically defined LOCA, SCA27B was the main cause of pure ataxia, RFC1-related disease of ataxia with neuropathy, and SPG7 of ataxia with spasticity.

CONCLUSION

We showed that SCA27B is the most common cause of LOCA in our cohort. Our results support the use of FGF14 GAA repeat expansion screening as a first-tier genetic test in patients with LOCA.

A Set of Reliable Samples for the Study of Biomarkers for the Early Diagnosis of Parkinson's Disease

Background

Parkinson's disease (PD) is a progressive neurodegenerative disorder, diagnosed according to the clinical criteria that occur in already advanced stages of PD. The definition of biomarkers for the early diagnosis of PD represents a challenge that might improve treatment and avoid complications in this disease. Therefore, we propose a set of reliable samples for the identification of altered metabolites to find potential prognostic biomarkers for early PD.

Methods

This case–control study included plasma samples of 12 patients with PD and 21 control subjects, from the Spanish European Prospective Investigation into Cancer and Nutrition (EPIC)-Navarra cohort, part of the EPIC-Spain study. All the case samples were provided by healthy volunteers who were followed-up for 15.9 (±4.1) years and developed PD disease later on, after the sample collection. Liquid chromatography coupled to tandem mass spectrometry was used for the analysis of samples.

Results

Out of 40 that were selected and studied due to their involvement in established cases of PD, seven significantly different metabolites between PD cases and healthy control subjects were obtained in this study (benzoic acid, palmitic acid, oleic acid, stearic acid, myo-inositol, sorbitol, and quinolinic acid). These metabolites are related to mitochondrial dysfunction, the oxidative stress, and the mechanisms of energy production.

Conclusion

We propose the samples from the EPIC study as reliable and invaluable samples for the search of early biomarkers of PD. Likewise, this study might also be a starting point in the establishment of a well-founded panel of metabolites that can be used for the early detection of this disease.

Prognostic biomarkers of Parkinson's disease in the Spanish EPIC cohort: a multiplatform metabolomics approach

The lack of knowledge about the onset and progression of Parkinson's disease (PD) hampers its early diagnosis and treatment. Metabolomics might shed light on the PD imprint seeking a broader view of the biochemical remodeling induced by this disease in an early and pre-symptomatic stage and unveiling potential biomarkers. To achieve this goal, we took advantage of the great potential of the European Prospective Study on Nutrition and Cancer (EPIC) cohort to apply metabolomics searching for early diagnostic PD markers. This cohort consisted of healthy volunteers that were followed for around 15 years until June 2011 to ascertain incident PD. For this untargeted metabolomics-based study, baseline preclinical plasma samples of 39 randomly selected individuals that developed PD (Pre-PD group) and the corresponding control group were analyzed using a multiplatform approach. Data were statistically analyzed and exposed alterations in 33 metabolites levels, including significantly lower levels of free fatty acids (FFAs) in the preclinical samples from PD subjects. These results were then validated by adopting a targeted HPLC-QqQ-MS approach. After integrating all the metabolites affected, our finding revealed alterations in FFAs metabolism, mitochondrial dysfunction, oxidative stress, and gut-brain axis dysregulation long before the development of PD hallmarks. Although the biological purpose of these events is still unknown, the remodeled metabolic pathways highlighted in this work might be considered worthy prognostic biomarkers of early prodromal PD. The findings revealed by this work are of inestimable value since this is the first study conducted with samples collected many years before the disease development.

Analysis of Fine Motor Skills in Essential Tremor: Combining Neuroimaging and Handwriting Biomarkers for Early Management

Essential tremor (ET) is a highly prevalent neurological disorder characterized by action-induced tremors involving the hand, voice, head, and/or face. Importantly, hand tremor is present in nearly all forms of ET, resulting in impaired fine motor skills and diminished quality of life. To advance early diagnostic approaches for ET, automated handwriting tasks and magnetic resonance imaging (MRI) offer an opportunity to develop early essential clinical biomarkers. In this study, we present a novel approach for the early clinical diagnosis and monitoring of ET based on integrating handwriting and neuroimaging analysis. We demonstrate how the analysis of fine motor skills, as measured by an automated Archimedes' spiral task, is correlated with neuroimaging biomarkers for ET. Together, we present a novel modeling approach that can serve as a complementary and promising support tool for the clinical diagnosis of ET and a large range of tremors.

A More Homogeneous Phenotype in Parkinson's Disease Related to R1441G Mutation in the LRRK2 Gene

Parkinson's disease (PD) is characterized by a great clinical heterogeneity. Nevertheless, the biological drivers of this heterogeneity have not been completely elucidated and are likely to be complex, arising from interactions between genetic, epigenetic, and environmental factors. Despite this heterogeneity, the clinical patterns of monogenic forms of PD have usually maintained a good clinical correlation with each mutation once a sufficient number of patients have been studied. Mutations in LRRK2 are the most commonly known genetic cause of autosomal dominant PD known to date. Furthermore, recent genome-wide association studies have revealed variations in LRRK2 as significant risk factors also for the development of sporadic PD. The LRRK2-R1441G mutation is especially frequent in the population of Basque ascent based on a possible founder effect, being responsible for almost 50% of cases of familial PD in our region, with a high penetrance. Curiously, Lewy bodies, considered the neuropathological hallmark of PD, are absent in a significant subset of LRRK2-PD cases. Indeed, these cases appear to be associated with a less aggressive primarily pure motor phenotype. The aim of our research is to examine the clinical phenotype of R1441G-PD patients, more homogeneous when we compare it with sporadic PD patients or with patients carrying other LRRK2 mutations, and reflect on the value of the observed correlation in the genetic forms of PD. The clinical heterogeneity of PD leads us to think that there may be as many different diseases as the number of people affected. Undoubtedly, genetics constitutes a relevant key player, as it may significantly influence the phenotype, with differences according to the mutation within the same gene, and not only in familial PD but also in sporadic forms. Thus, extending our knowledge regarding genetic forms of PD implies an expansion of knowledge regarding sporadic forms, and this may be relevant due to the future therapeutic implications of all forms of PD.

Discrete Cosine Transform for the Analysis of Essential Tremor

Essential tremor (ET) is the most common movement disorder. In fact, its prevalence is about 20 times higher than that of Parkinson's disease. In addition, studies have shown that a high percentage of cases, between 50 and 70%, are estimated to be of genetic origin. The gold standard test for diagnosis, monitoring and to differentiate between both pathologies is based on the drawing of the Archimedes' spiral. Our major challenge is to develop the simplest system able to correctly classify Archimedes' spirals, therefore we will exclusively use the information of the x and y coordinates. This is the minimum information provided by any digitizing device. We explore the use of features from drawings related to the Discrete Cosine Transform as part of a wider cross-study for the diagnosis of essential tremor held at Biodonostia. We compare the performance of these features against other classic and already analyzed ones. We outperform previous results using a very simple system and a reduced set of features. Because the system is simple, it will be possible to implement it in a portable device (microcontroller), which will receive the x and y coordinates and will issue the classification result. This can be done in real time, and therefore without needing any extra job from the medical team. In future works these new drawing-biomarkers will be integrated with the ones obtained in the previous Biodonostia study. Undoubtedly, the use of this technology and user-friendly tools based on indirect measures could provide remarkable social and economic benefits.

Ratios of proteins in cerebrospinal fluid in Parkinson's disease cognitive decline: prospective study

BACKGROUND

There is a need for biomarkers of dementia in PD.

OBJECTIVES

To determine if the levels of the main CSF proteins and their ratios are associated with deterioration in cognition and progression to dementia in the short to mid term.

METHODS

The Parkinson's Progression Markers Initiative database was used as an exploratory cohort, and a center-based cohort was used as a replication cohort. Amyloid ß1-42, total tau, threonine-181 phosphorylated tau, and α-synuclein in the CSF and the ratios of these proteins were assessed.

RESULTS

In the Parkinson's Progression Markers Initiative cohort (n = 281), the total tau/amyloid ß1-42, total tau/α-synuclein, total tau/amyloid ß1-42+α-synuclein, and amyloid ß1-42/total tau ratios were associated with a risk of progression to dementia over a 3-year follow-up. In the replication cohort (n = 40), the total tau/α-synuclein and total tau/amyloid ß1-42+α-synuclein ratios were associated with progression to dementia over a 41-month follow-up.

CONCLUSION

Ratios of the main proteins found in PD patient brain inclusions that can be measured in the CSF appear to have value as short- to mid-term predictors of dementia. © 2018 International Parkinson and Movement Disorder Society.

Automatic Analysis of Archimedes' Spiral for Characterization of Genetic Essential Tremor Based on Shannon's Entropy and Fractal Dimension

Among neural disorders related to movement, essential tremor has the highest prevalence; in fact, it is twenty times more common than Parkinson's disease. The drawing of the Archimedes' spiral is the gold standard test to distinguish between both pathologies. The aim of this paper is to select non-linear biomarkers based on the analysis of digital drawings. It belongs to a larger cross study for early diagnosis of essential tremor that also includes genetic information. The proposed automatic analysis system consists in a hybrid solution: Machine Learning paradigms and automatic selection of features based on statistical tests using medical criteria. Moreover, the selected biomarkers comprise not only commonly used linear features (static and dynamic), but also other non-linear ones: Shannon entropy and Fractal Dimension. The results are hopeful, and the developed tool can easily be adapted to users; and taking into account social and economic points of view, it could be very helpful in real complex environments.

Whole-exome sequencing associates novel CSMD1 gene mutations with familial Parkinson disease

OBJECTIVE

Despite the enormous advancements made in deciphering the genetic architecture of Parkinson disease (PD), the majority of PD is idiopathic, with single gene mutations explaining only a small proportion of the cases.

METHODS

In this study, we clinically evaluated 2 unrelated Spanish families diagnosed with PD, in which known PD genes were previously excluded, and performed whole-exome sequencing analyses in affected individuals for disease gene identification.

RESULTS

Patients were diagnosed with typical PD without relevant distinctive symptoms. Two different novel mutations were identified in the CSMD1 gene. The CSMD1 gene, which encodes a complement control protein that is known to participate in the complement activation and inflammation in the developing CNS, was previously shown to be associated with the risk of PD in a genome-wide association study.

CONCLUSIONS

We conclude that the CSMD1 mutations identified in this study might be responsible for the PD phenotype observed in our examined patients. This, along with previous reported studies, may suggest the complement pathway as an important therapeutic target for PD and other neurodegenerative diseases.

Genetic Mutation Analysis of Parkinson's Disease Patients Using Multigene Next-Generation Sequencing Panels

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder, affecting millions of people. Genome-wide association studies (GWAS) have found >25 genetic risk factors and at least 15 loci directly associated with PD. Recent advances in new next-generation DNA sequencing technologies, such as the semiconductor-based Ion Torrent platform, make multigene sequencing cheaper, faster, and more reliable.

OBJECTIVES

Our objective was to test the power of this next-generation sequencing technology to analyze large samples by screening the majority of the most relevant PD-related genes known for single and compound mutations.

METHODS

To archive a rapid, robust, and cost-effective genetic analysis of a PD cohort, we designed a multiplex, polymerase chain reaction (PCR)-based primer panel to amplify and sequence coding exons of 15 PD-associated genes (SNCA, LRRK2, PARK2, PINK1, PARK7, GIGYF2, ATP13A2, UCHL1, PLA2G6, FBXO7, EIF4G1, VPS35, ACMSD, APOE, and GBA). We conducted parallel sequencing using the Ion Torrent Personal Genome Machine(®) system to detect mutations in 92 blood DNA samples from PD patients.

RESULTS

After bioinformatics analysis and filtering, 95.13 % coverage of the targeted region was obtained at >40-fold mean coverage. The results revealed 44 previously documented variants in these 15 genes, with five revealed as pathogenic. We also discovered six novel variants, five of which had an in silico prediction of being pathogenic.

CONCLUSIONS

Benchtop next-generation sequencing is a powerful method for genetic screening for PD. Our results indicated that it yielded a high frequency of discovery (66 %; n = 92) of variants in carriers from an enriched Spanish PD sample.

A protective personal factor against disability and dependence in the elderly: an ordinal regression analysis with nine geographically-defined samples from Spain

BACKGROUND

Sense of Coherence (SOC) is defined as a tendency to perceive life experiences as comprehensible, manageable and meaningful. The construct is split in three major domains: Comprehensibility, Manageability, and Meaningfulness. SOC has been associated with successful coping strategies in the face of illness and traumatic events and is a predictor of self-reported and objective health in a variety of contexts. In the present study we aim to evaluate the association of SOC with disability and dependence in Spanish elders.

METHODS

A total of 377 participants aged 75 years or over from nine locations across Spain participated in the study (Mean age: 80.9 years; 65.3% women). SOC levels were considered independent variables in two ordinal logistic models on disability and dependence, respectively. Disability was established with the World health Organization-Disability Assessment Schedule 2.0 (36-item version), while dependence was measured with the Extended Katz Index on personal and instrumental activities of daily living. The models included personal (sex, age, social contacts, availability of an intimate confidant), environmental (municipality size, access to social resources) and health-related covariates (morbidity).

RESULTS

High Meaningfulness was a strong protective factor against both disability (Odds Ratio [OR] = 0.50; 95% Confidence Interval [CI] = 0.29-0.87) and dependence (OR = 0.33; 95% CI = 0.19-0.58) while moderate and high Comprehensibility was protective for disability (OR = 0.40; 95% CI = 0.22-0.70 and OR = 0.39; 95%CI = 0.21-0.74), but not for dependence. Easy access to social and health resources was also highly protective against both disability and dependence.

CONCLUSIONS

Our results are consistent with the view that high levels of SOC are protective against disability and dependence in the elderly. Elderly individuals with limited access to social and health resources and with low SOC may be a group at risk for dependence and disability in Spain.

SCN4A pore mutation pathogenetically contributes to autosomal dominant essential tremor and may increase susceptibility to epilepsy

Essential tremor (ET) is the most prevalent movement disorder, affecting millions of people in the USA. Although a positive family history is one of the most important risk factors for ET, the genetic causes of ET remain unknown. In an attempt to identify genetic causes for ET, we performed whole-exome sequencing analyses in a large Spanish family with ET, in which two patients also developed epilepsy. To further assess pathogenicity, site-directed mutagenesis, mouse and human brain expression analyses, and patch clamp techniques were performed. A disease-segregating mutation (p.Gly1537Ser) in the SCN4A gene was identified. Posterior functional analyses demonstrated that more rapid kinetics at near-threshold potentials altered ion selectivity and facilitated the conductance of both potassium and ammonium ions, which could contribute to tremor and increase susceptibility to epilepsy, respectively. In this report, for the first time, we associated the genetic variability of SCN4A with the development of essential tremor, which adds ET to the growing list of neurological channelopathies.

Parkinson's Disease Case Ascertainment in the EPIC Cohort: The NeuroEPIC4PD Study

BACKGROUND/AIMS

Large epidemiological prospective studies represent an important opportunity for investigating risk factors for rare diseases such as Parkinson's disease (PD). Here we describe the procedures we used for ascertaining PD cases in the EPIC (European Prospective Investigation into Cancer and Nutrition) study.

METHODS

The following three-phase procedure was used: (1) elaboration of a NeuroEPIC4PD template for clinical data collection, (2) identification of all potential PD cases via record linkage and (3) validation of the diagnosis through clinical record revision, in a population of 220,494 subjects recruited in 7 European countries. All cases were labelled with the NeuroEPIC4PD diagnoses of 'definite', 'very likely', 'probable', or 'possible' PD.

RESULTS

A total of 881 PD cases were identified, with over 2,741,780 person-years of follow-up (199 definite, 275 very likely, 146 probable, and 261 possible). Of these, 734 were incident cases. The mean age at diagnosis was 67.9 years (SD 9.2) and 458 patients (52.0%) were men. Bradykinesia was the most frequent presenting motor sign (76.5%). Tremor-dominant and akinetic rigid forms of PD were the most common types of PD. A total of 289 patients (32.8%) were dead at the time of the last follow-up.

CONCLUSIONS

This exercise proved that it is feasible to ascertain PD in large population-based cohort studies and offers a potential framework to be replicated in similar studies.

SORT1 Mutation Resulting in Sortilin Deficiency and p75(NTR) Upregulation in a Family With Essential Tremor

*These authors contributed equally to this work.

Essential tremor (ET) is the most prevalent movement disorder affecting millions of people in the United States. Although a positive family history is one of the most important risk factors for ET, the genetic causes of ET remain unknown. In this study, whole exome sequencing and subsequent approaches were performed in a family with an autosomal dominant form of early-onset ET. Functional analyses including mutagenesis, cell culture, gene expression, enzyme-linked immunosorbent, and apoptosis assays were also performed. A disease-segregating mutation (p.Gly171Ala), absent in normal population, was identified in the SORT1 gene. The p.Gly171Ala mutation was shown not only to impair the expression of its encoding protein sortilin but also the mRNA levels of its binding partner p75 neurotrophin receptor that is known to be implicated in brain injury, neuronal apoptosis, and neurotransmission.

Cognitive dysfunction in Parkinson's disease related to the R1441G mutation in LRRK2

OBJECTIVE

The neuropsychological characteristics of patients with Parkinson's Disease (PD) associated with R1441G mutation in the LRRK2 gene (R1441G-PD) are not well known. The aim of this study was to examine the cognitive status and mood of R1441G-PD patients.

METHODS

Thirty patients with R1441G-PD were compared with thirty idiopathic PD (i-PD) patients who were matched by age, sex, education, disease onset age and duration, using a comprehensive battery of neuropsychological test, and considering the Movement Disorder Society (MDS) criteria for the diagnosis of Mild Cognitive Impairment (PD-MCI) and dementia (PD-Dementia).

RESULTS

The mean scores in the depression and anxiety scales were similar in the two groups. Depressive symptoms were detected in 31.8% of R1441G-PD and 25% of i-PD patients and anxiety symptoms were evident in 4.5% and 15%, respectively, but the differences were not significant. The only neuropsychological test on which there was a significantly worse performance in the R1441G-PD group was the Boston naming test but the difference became not significant when Bonferroni's correction was applied. The prevalence of PD-MCI was 30% in both R1441G-PD and i-PD, with no differences in the number and type of domains altered given that executive function, memory and attention were mainly affected. PD-Dementia was diagnosed in 13.3% (n = 4) of R1441G-PD and 26.7% (n = 8) of i-PD patients (difference was not significant).

CONCLUSION

In conclusion, significant differences were not detected between R1441G-PD and i-PD in cognitive, depression and anxiety scales, or PD-MCI and PD-Dementia prevalence, and the cognitive profile was identical in the two groups.

Prevalence of cancer in Parkinson's disease related to R1441G and G2019S mutations in LRRK2

An inverse relationship between Parkinson's disease (PD) and cancer has been described. However, the association between cancers and genetic forms of PD, in particular the R1441G mutation in the LRRK2 gene, is not well known. The objective of this work was to analyze cancer prevalence in PD patients with R1441G or G2019S mutations in LRRK2, and in idiopathic PD (iPD). A total of 732 patients with PD (70 and 25 carriers of R1441G or G2019S mutations, respectively), and 177 controls, were linked using a population-based cancer registry of the Spanish province of Gipuzkoa. Cancer prevalence was not significantly higher in PD-G2019S carriers (20%) than in PD-R1441G carriers (14.3%), iPD (13.8%), or controls (12.5%). With the exception of a high prevalence of hematological cancers (crude odds ratio of 7.1) in the R1441G group, specific cancer types were not increased in PD mutation carriers. In both the carrier and iPD groups, cancers were diagnosed after the onset of PD. PD patients had a similar prevalence of cancer to control subjects. There was no increased association between G2019S or R1441G mutations and any type of cancer. Although there was a higher prevalence of hematological cancers in the R1441G group, the low number of such cancers overall makes this finding of uncertain significance. There was a slightly higher but not statistically significant prevalence of non-skin cancers in the G2019S group, suggesting that further study to evaluate the association should be undertaken prior to ascribing an increased cancer risk to this population.

Lewy bodies under atomic force microscope

Lewy bodies are the hallmark of Parkinson disease and their sophisticated analysis will undoubtedly elucidate the pathogenic process. They have been studied by using different microscopic tools. The authors have used atomic force microscopy (AFM) to study the ultramicrotom cut postmortem brain tissue of Parkinson disease patients. Under the same preparation conditions, they have found aggregated fibrillary nanostructures in Lewy bodies, as well as a loss of connections between neurons located in other parts of the substantia nigra. Although these results are preliminary and descriptive in nature, this paper reports the application of a novel and intriguing technique. Further studies including the study of cortical LB and Lewy neurites will be needed to determine the full potential of AFM in the study of the pathogenesis of cell death in Parkinson disease and other synucleinopathies.

The ACMSD gene, involved in tryptophan metabolism, is mutated in a family with cortical myoclonus, epilepsy, and parkinsonism

Familial cortical myoclonic tremor and epilepsy is a phenotypically and genetically heterogeneous autosomal dominant disorder characterized by the presence of cortical myoclonic tremor and epilepsy that is often accompanied by additional neurological features. Despite the numerous familial studies performed and the number of loci identified, there is no gene associated with this syndrome. It is expected that through the application of novel genomic technologies, such as whole exome sequencing and whole genome sequencing, a substantial number of novel genes will come to light in the coming years. In this study, we describe the identification of two disease-segregating mutations in a large family featuring cortical myoclonic tremor with epilepsy and parkinsonism. Due to the previous association of ACMSD deficiency with the development of epileptic seizures, we concluded that the identified nonsense mutation in the ACMSD gene, which encodes for a critical enzyme of the kynurenine pathway of the tryptophan metabolism, is the disease-segregating mutation most likely to be responsible for the phenotype described in our family. This finding not only reveals the identification of the first gene associated with familial cortical myoclonic tremor and epilepsy but also discloses the kynurenine pathway as a potential therapeutic target for the treatment of this devastating syndrome.

KEY MESSAGE

ACMSD is mutated in a family with cortical myoclonus, epilepsy, and parkinsonism. ACMSD mutation contributes to the development of FCMTE QA accumulation is likely to play an important role in the pathogenesis of FCMTE. The kynurenine pathway as a potential drug target for the treatment of epilepsy.

Αlpha-synuclein levels in blood plasma from LRRK2 mutation carriers

The diagnosis of Parkinson's disease (PD) remains primarily a clinical issue, based mainly on phenotypic patterns. The identification of biomarkers capable of permitting the preclinical detection of PD is critically needed. α-Synuclein is a key protein in PD, with missense and multiplication mutations in the gene encoding α-synuclein (SNCA) having been reported in familial cases of PD, and accumulation of the protein identified in Lewy bodies (LBs) and Lewy neurites (LNs) in affected brain regions. With the objective of validating the use of α-synuclein as a clinical or progressive biomarker in an accessible tissue, we used an enzyme-linked immunosorbent assay (ELISA) to measure α-synuclein levels in the peripheral blood plasma of idiopathic PD and LRRK2 mutation carrier patients and compared our findings with healthy control subjects. Compared to healthy controls, we found a significant decrease in plasma total α-synuclein levels in idiopathic PD (iPD) patients (n = 134, p = 0.010). However, the reduction was less significant in patients who were LRRK2 mutation carriers (n = 32, p = 0.133). This lack of significance could be due to the small number of individuals employed in this group. No predictive value of total α-synuclein in the diagnosis of PD was found in a receiver operating characteristic (ROC) curve analysis. Although this is a pilot study requiring corroboration on a larger cohort of patients, our results highlight the possible use of plasma α-synuclein as a biomarker for PD.

Medical, environmental and personal factors of disability in the elderly in Spain: a screening survey based on the International Classification of Functioning

OBJECTIVES

The International Classification of Functioning, Disability and Health (ICF) advocates a multifactorial and multifaceted conceptualization of disability. The objective of this study was to ascertain major medical, environmental and personal determinants of severe/extreme disability among the elderly population in Spain. The assessment scheme was consistent with the ICF model of disability.

METHODS

Nine populations contributed probabilistic or geographically-defined samples following a two-phase screening design. The Mini-Mental State Examination and the 12-item version of the World Health Organization-Disability Assessment Schedule, 2(nd) ed. (WHO-DAS II), were used as cognitive and disability screening tools, respectively. Positively screened individuals underwent clinical work-up for dementia and were administered the 36-item version of the WHO-DAS II to estimate ICF disability levels. We used logistic regression for the purposes of data combination, adjusted for age and sex in all analyses.

RESULTS

The sample was composed of 503 participants aged ≥ 75 years. Alzheimeŕs disease and depression were highly predictive of severe/extreme disability (OR: 17.40, 3.71). Good access to social services was strongly associated with a low level or absence of disability (OR: 0.05 to 0.18). Very difficult access to services and having dementia or another psychiatric disorder were associated with an increase in disability (OR: 66.06). There was also a significant interaction effect between access to services and neurological disorders (OR: 12.74).

CONCLUSIONS

Disability is highly prevalent among the Spanish elderly and is influenced by medical, social and personal factors. Disability could potentially be reduced by ensuring access to social services, preventing dementia and stroke, and treating depression.

Prevalence and European comparison of dementia in a ≥75-year-old composite population in Spain

OBJECTIVES

To estimate dementia prevalence in Spain.

MATERIALS AND METHODS

Nine probabilistic and geographically defined samples participated. A screening design based on the MMSE was implemented. Positively screened individuals underwent clinical evaluation. The total number of cases in Spain was estimated. Prevalence was confronted to that of other European countries.

RESULTS

Five hundred and forty-six persons aged ≥75 participated, 49 had dementia (35 with Alzheimer's disease [AD], 10 with vascular dementia [VD], 4 other; 25 first diagnosed in the study). Age- and sex-adjusted prevalence and estimated nationwide cases were 7.5% (95% CI 5.4-9.7), 5.6 (95% CI 3.7-7.5) and 1.4 (95% CI 0.5-2.3), and 290,000 (95% CI 208,000-372,000), 214,000 (95% CI 141,000-288,000) and 54,000 (95% CI 20,000-88,000) for dementia, AD and VD, respectively.

CONCLUSIONS

Dementia prevalence in Spain is comparable to other European populations, while a high number of undiagnosed cases live in the community. The potential impact of Mediterranean diet, hypertension control and decreasing vascular risk factors is discussed.

Prevalence of disability in a composite ≥75 year-old population in Spain: a screening survey based on the International Classification of Functioning

Background

The prevalence and predictors of functional status and disability of elderly people have been studied in several European countries including Spain. However, there has been no population-based study incorporating the International Classification of Functioning, Disability and Health (ICF) framework as the basis for assessing disability. The present study reports prevalence rates for mild, moderate, and severe/extreme disability by the domains of activities and participation of the ICF.

Methods

Nine populations surveyed in previous prevalence studies contributed probabilistic and geographically defined samples in June 2005. The study sample was composed of 503 subjects aged ≥75 years. We implemented a two-phase screening design using the MMSE and the World Health Organization-Disability Assessment Schedule 2^nd edition (WHO-DAS II, 12 items) as cognitive and disability screening tools, respectively. Participants scoring within the positive range of the disability screening were administered the full WHO-DAS II (36 items; score range: 0-100) assessing the following areas: Understanding and communication, Getting along with people, Life activities, Getting around, Participation in society, and Self-care. Each disability area assessed by WHO-DAS II (36 items) was reported according to the ICF severity ranges (No problem, 0-4; Mild disability, 5-24; Moderate disability, 25-49; Severe/Extreme disability, 50-100).

Results

The age-adjusted disability prevalence figures were: 39.17 ± 2.18%, 15.31 ± 1.61%, and 10.14 ± 1.35% for mild, moderate, and severe/extreme disability, respectively. Severe and extreme disability prevalence in mobility and life activities was three times higher than the average, and highest among women. Sex variations were minimal, although life activities for women of 85 years and over had more severe/extreme disability as compared to men (OR = 5.15 95% CI 3.19-8.32).

Conclusions

Disability is highly prevalent among the Spanish elderly. Sex- and age-specific variations of disability are associated with particular disability domains.

What contributes to driving ability in Parkinson's disease

PURPOSE

To determine the most significant clinical predictors that influence driving ability in Parkinson disease (PD).

METHODS

National-multi-centre, cross-sectional study covering PD outpatients. Clinical assessment was based on the following questionnaires: cognition (SCOPA-Cog); motor impairment and disabilities (SCOPA motor); depression/anxiety; sleep (SCOPA-Sleep); psychosis and severity/global impairment (HY and CISI-PD). Driving status data was obtained using a standardized questionnaire. Comparisons between drivers and ex-drivers were calculated using chi(2) and Student t-tests as appropriate. Multi-variate logistic regression analysis was performed to identify independent driving ability clinical predictors.

RESULTS

Compared with the drivers, the ex-drivers were older (p = 0.00005), had longer disease duration (p = 0.03), had more overall cognitive dysfunction (p = 0.004) and had greater motor impairment, as measured by the CISI (p = 0.02), HY stage (p = 0.034) and by the SCOPA-motor scale (p = 0.002) and difficulty in activities of daily life (p = 0.002). In the regression model analysis, aging and ADL impairment were the principal clinical predictors that differentiated drivers from ex-drivers.

CONCLUSIONS

Although overall driving impairment in PD is associated with advancing disease severity, driving ability seems to be more strongly influenced by age and ADL impairment. Multi-disciplinary teams are required to assess driving ability in patients with PD and develop rehabilitation measures for safer driving.

"Frontotemporoparietal" dementia: clinical phenotype associated with the c.709-1G>A PGRN mutation

BACKGROUND

Mutations in the progranulin gene (PGRN) are a major cause of frontotemporal lobar degeneration with tau-negative and ubiquitin-positive neuronal inclusions. Most previous studies aimed at characterizing the clinical and neuropsychological phenotype of PGRN mutation carriers included patients with different PGRN mutations, assuming that the common proposed pathogenetic mechanism of haploinsufficiency will lead to a comparable phenotype.

METHODS

We studied 21 patients with a single pathogenic splicing mutation in the PGRN gene (c.709-1G>A) in the same tertiary referral center using homogenous diagnostic criteria and protocols. All patients were of Basque descent.

RESULTS

Patients exhibited a variable phenotype both in age at onset and initial symptoms. Behavioral variant frontotemporal dementia (52.4%) and progressive nonfluent aphasia (23.8%) were the most common presenting syndromes. Apathy was the most common behavioral symptom. Patients developed a relatively rapidly progressive dementia with features that led to a secondary diagnosis in 61.9% of cases 2 years after primary diagnosis. Notably, this secondary or tertiary diagnosis was corticobasal syndrome in 47.6% of cases, which confirmed the neuropsychological features of parietal lobe dysfunction seen at the initial assessment in 81.8% of patients.

CONCLUSIONS

Patients carrying the c.709-1G>A mutation in the PGRN gene showed heterogeneous clinical and neuropsychological features and commonly developed corticobasal syndrome as the disease progressed.

Prevalence of dementia and major dementia subtypes in Spanish populations: a reanalysis of dementia prevalence surveys, 1990-2008

Background

This study describes the prevalence of dementia and major dementia subtypes in Spanish elderly.

Methods

We identified screening surveys, both published and unpublished, in Spanish populations, which fulfilled specific quality criteria and targeted prevalence of dementia in populations aged 70 years and above. Surveys covering 13 geographically different populations were selected (prevalence period: 1990-2008). Authors of original surveys provided methodological details of their studies through a systematic questionnaire and also raw age-specific data. Prevalence data were compared using direct adjustment and logistic regression.

Results

The reanalyzed study population (aged 70 year and above) was composed of Central and North-Eastern Spanish sub-populations obtained from 9 surveys and totaled 12,232 persons and 1,194 cases of dementia (707 of Alzheimer's disease, 238 of vascular dementia). Results showed high variation in age- and sex-specific prevalence across studies. The reanalyzed prevalence of dementia was significantly higher in women; increased with age, particularly for Alzheimer's disease; and displayed a significant geographical variation among men. Prevalence was lowest in surveys reporting participation below 85%, studies referred to urban-mixed populations and populations diagnosed by psychiatrists.

Conclusion

Prevalence of dementia and Alzheimer's disease in Central and North-Eastern Spain is higher in females, increases with age, and displays considerable geographic variation that may be method-related. People suffering from dementia and Alzheimer's disease in Spain may approach 600,000 and 400,000 respectively. However, existing studies may not be completely appropriate to infer prevalence of dementia and its subtypes in Spain until surveys in Southern Spain are conducted.

[Tremor: update and controversy]

INTRODUCTION

Tremor is the most common movement disorder. The differential diagnosis on its origin is sometimes difficult and the number of conditions that include this symptom as part of their clinical spectrum continues to increase.

AIMS

To provide an update on aspects that may help in the process of diagnosis, to review the main lines of therapy and to reflect on tremor within the context of Parkinson's disease.

DEVELOPMENT

Complementary techniques in the study of Parkinson's disease, such as DaT-SCAN or the study of the cardiac sympathetic pathway by means of cardiac scintigraphy with meta-iodobenzylguanidine (MIBG), have helped in the aetiological diagnosis of this symptom; nevertheless, the patient's clinical history continues to be the main source of information for an accurate diagnosis. Pharmacologically, the therapeutic approach has varied very little and the outcomes of surgical procedures are still described as an alternative in medication-resistant cases. In Parkinson's disease, tremor at rest is a characteristic clinical sign that comprises a series of peculiarities, and the interrelation between essential tremor and this disease is always a controversial issue. The appearance of cases that have been diagnosed as Parkinson's disease, but in which the nigrostriatal pathway remains intact, opens up the spectrum even wider.

CONCLUSIONS

In this paper we review the data available today that help in the differential diagnosis of tremor; the particularities concerning Parkinson's disease from the diagnostic, therapeutic and genotypic point of view are also discussed.

Mutations in progranulin gene: clinical, pathological, and ribonucleic acid expression findings

BACKGROUND

There is an increasing interest in the clinico-pathological correlation of mutations in progranulin (PGRN) and frontotemporal lobar degeneration (FTLD) complex diseases. We aim to study the PGRN expression variability in patients with different clinical features for a better understanding of its roles in FTLD disease.

METHODS

We sequenced the PGRN gene in 72 patients suffering from FTLD (25 familial and 47 sporadic cases) and in 24 asymptomatic at-risk relatives. We also analyzed PGRN expression in blood by quantitative real-time polymerase chain reaction from 37 patients, 8 asymptomatic mutation carriers, and 10 control subjects as well as in brain tissue from 16 patients and 9 control subjects.

RESULTS

Four novel mutations were associated with familial and sporadic FTLD and familial dementia associated with amyotrophic lateral sclerosis. We identified a close association between the IVS6-1G>A mutation in PGRN and corticobasal syndrome. Brain tissue was available for carriers of two of the four mutations (IVS6-1 G>A and P357HfsX3). Immunohistochemical analysis revealed ubiquitin- and TDP-43positive and tau/alpha-synuclein negative immunoreactive neuronal intranuclear inclusions. The relative expression of PGRN in the clinical sample was significantly lower in carriers of the IVS6-1 G>A than in control subjects.

CONCLUSIONS

Progranulopathies are a major cause of the main phenotypes included in the FTLD complex. According to our results, the level of expression of PGRN in blood could be a useful marker both for diagnostics of part of the spectrum of FTLD conditions and for monitoring future treatments that might boost the level of PGRN in this disorder.

[Prevalence of vascular risk factors among Spanish populations aged 70 years and over, as reported in door-to-door studies on neurological diseases]

INTRODUCTION

The aim of this study was to re-analyze door-to-door studies on neurological diseases among the elderly, in which vascular risk factors (VRF) were studied, describing methodological characteristics and prevalence of VRF.

METHODS

The surveys were identified in two phases. They were aimed at ascertaining prevalence of stroke, dementias or Parkinsonisms and, at the time of individual screening, had collected data on at least three of the following VRF: arterial hypertension (AHT), smoking habit, diabetes mellitus and hypercholesterolemia. A questionnaire was drawn up to collect the data reported in each study, and a database was constructed. VRF prevalences were quantified and analyzed using logistic regression.

RESULTS

The total of the re-analyzed population was 12,510 persons aged 70 years and over, residents in seven geographic areas during the period 1994-2002. Information available on VRF was essentially self-reported. The prevalence of self-reported AHT was 25.7 % in men and 44.2 % in women, and that of measured AHT was 61 % and 71.9 %, respectively. Populations with arterial pressure obtained by direct measurement registered 138 higher risks (OR: 1.74; 95 % CI: 1.51-2.01, and OR: 1.48; 95% CI: 1.33-1.64). Reported prevalence of diabetes, hypercholesterolemia and smoking habit were 14.3 %, 23.3% and 8.5 %, respectively.

CONCLUSIONS

There was a high prevalence of VRF among the Spanish elderly population. However, its relationship with dementia, Parkinsonisms and cerebrovascular disease could not be studied due to the poor quality of the VRF data. The differences between measured and self-reported arterial pressure suggest the existence of undetected AHT and wide scope for prevention.

[A pilot study on a specific measure for sleep disorders in Parkinson's disease: SCOPA-Sleep]

INTRODUCTION

There is a high prevalence of sleep disorders in Parkinson's disease (PD). AIMS. To assess some basic metric attributes of the SCOPA-Sleep scale, a measure for PD patients; secondary objective: to check the impact caused by the sleep disorder on the health-related quality of life (HRQoL) of patients and their caregivers.

SUBJECTS AND METHODS

68 PD patients and their main caregivers; measures: Hoehn and Yahr staging, SCOPA-Motor, Clinical Impression of Severity Index (CISI-PD), PDSS, Hospital Anxiety and Depression Scale, SCOPA-Psychosocial, and EuroQoL. Carers filled in a PDSS questionnaire about patient sleep and HRQoL measures (SF-36, EuroQoL). SCOPA-Sleep acceptability, scaling assumptions, internal consistency, construct validity and precision were determined.

RESULTS

SCOPA-Sleep acceptability and scaling assumptions resulted satisfactory, although the nocturnal sleep subescale (SC-Ns) showed a mild ceiling effect (22.1%) and a defective convergent validity was found for daytime sleepiness (SC-Ds) item 6. Internal consistency also was satisfactory for both scales (alpha = 0.84 and 0.75, respectively). The correlation between SC-Ns and PDSS was high (rs = -0.70), as it was between SC-Ns and PDSS questionnaire by caregiver (rs = -0.53). The corresponding coefficients with the SC-Ds gained lower values (rs = -0.41 y -0.50). Standard error of measurement was 1.45 for the SC-Ns and 1.76 for the SC-Ds. Both, patient and caregiver HRQoL showed a loose association with the sleep measures.

CONCLUSION

SCOPA-Sleep is a feasible, consistent, and useful scale for assessment of sleep disorder in PD patients. A weak association between sleep disorder and HRQoL was found.

Stroke prevalence among the Spanish elderly: an analysis based on screening surveys

BACKGROUND

This study sought to describe stroke prevalence in Spanish elderly populations and compare it against that of other European countries.

METHODS

We identified screening surveys--both published and unpublished--in Spanish populations, which fulfilled specific quality requirements and targeted prevalence of stroke in populations aged 70 years and over. Surveys covering seven geographically different populations with prevalence years in the period 1991-2002 were selected, and the respective authors were then asked to provide descriptions of the methodology and raw age-specific data by completing a questionnaire. In addition, five reported screening surveys in European populations furnished useful data for comparison purposes. Prevalence data were combined, using direct adjustment and logistic regression.

RESULTS

The overall study population, resident in central and north-eastern Spain, totalled 10,647 persons and yielded 715 cases. Age-adjusted prevalences, using the European standard population, were 7.3% for men, 5.6% for women, and 6.4% for both sexes. Prevalence was significantly lower in women, OR 0.79 95% CI 0.68-0.93, increased with age, particularly among women, and displayed a threefold spatial variation with statistically significant differences. Prevalences were highest, 8.7%, in suburban, and lowest, 3.8%, in rural populations. Compared to pooled Spanish populations, statistically significant differences were seen in eight Italian populations, OR 1.39 95% CI (1.18-1.64), and in Kungsholmen, Sweden, OR 0.40 95% CI (0.27-0.58).

CONCLUSION

Prevalence in central and north-eastern Spain is higher in males and in suburban areas, and displays a threefold geographic variation, with women constituting the majority of elderly stroke sufferers. Compared to reported European data, stroke prevalence in Spain can be said to be medium and presents similar age- and sex-specific traits.

Early onset parkinsonism in dementia lacking distinct histopathological features

Dementia lacking distinct histopathological features (DLDHF) belongs to the frontotemporal dementia syndromes. Behavioral, cognitive and motor symptoms are its usual clinical manifestations. However, considerable heterogeneity exists and no evident clinicopathological correlations can be performed. We report a patient who presented with a very unusual combination of behavioral abnormalities and prominent early parkinsonism progressing to a severe dementia. Pathological studies confirmed DLDHF with severe frontal and striatal neuronal loss and gliosis.

Dementia, Stroke and Parkinson’s Disease in Spanish Populations: A Review of Door-to-Door Prevalence Surveys

We identified 14 door-to-door prevalence surveys on dementia, parkinsonism or stroke in Spanish populations fulfilling specific criteria and combined selected age- and sex-specific data using logistic regression and taking Pamplona as a reference. The prevalence of dementia and of Alzheimer's disease varied significantly with space. However, the largest variation was seen for vascular dementia: odds ratio (OR) and 95% confidence interval (CI) for Gerona were 6.42 (3.23-12.3) in women and 2.30 (1.10-4.79) in men. Stroke was particularly frequent among Arevalo's women, with OR 2.10 and 95% CI 1.26-3.49. The prevalence of Parkinson's disease was twofold higher in Cantalejo. Although differences in methodology make the interpretation of results problematic, the prevalence of stroke and vascular dementia in Spain seems to vary spatially, indicating a space for prevention.

Prevalence of Parkinson?s disease and other types of Parkinsonism

OBJECTIVES

To assess the prevalence of Parkinson's disease and parkinsonism in two Spanish populations (Irun and Hondarribia, Bidasoa Region) and to compare the results with those of similar surveys.

METHODS

The survey included 2000 participants aged 65 years or older in a door-to-door, three-phase design. In the screening phase we used the SNES (Sicilian Neuro-Epidemiologic Study) screening questionnaire, which has 100% sensitivity. In phases 2 and 3 we carried out a 3-year follow-up of all cases diagnosed with parkinsonism in phase 2. Progressively stricter diagnostic criteria were chosen in order to minimize the impact of false positives on the final results.

RESULTS

The prevalence of Parkinson's disease (PD) was 1.5 % (95% confidence interval, 0.9 to 2.3) and the prevalence of other types of parkinsonism (OP) was 1.1 % (95% confidence interval 0.6 to 1.9). The overall prevalence by age group was 0.4 % (65-74 years), 4.7% (75-84 years), and 2.9% (> or =85 years) for Parkinson's disease and 0.7%, 2%, and 3.9 % for parkinsonism, respectively. The other parkinsonism prevalence was 1.3 % in men and 1.6 % in women.

CONCLUSIONS

These prevalence rates are similar than those found in studies made in other European countries. The prevalence of both Parkinson's disease and other types of parkinsonism increased with age, with no significant differences between men and women.

The validity of Hodkinson's Abbreviated Mental Test for dementia screening in Guipuzcoa, Spain

The objective of this research was to evaluate the validity of Hodkinson's Abbreviated Mental Test (AMT) in screening for dementia and to identify the optimum cut-off point to use in a prevalence survey. The study included two groups of persons: (i) a random sample of 183 individuals selected from census data, 96 of whom completed the study and (ii) another 36 persons with dementia were selected from a hospital outpatients department by sampling consecutive cases. The DSM-IV criteria were used as the "gold standard" to establish a diagnosis of dementia. The AMT was administered to the 132 participants who subsequently underwent independent clinical evaluation. In the community sample, 11 persons were diagnosed with dementia and 85 without. In the total sample, a score of 7 maximizes the efficacy of the test. The sensitivity for this cut-off point is 91.5% (78.7-97.2%) and the specificity is 82.4% (72.2-89.5%). A score of 9 gives 100% sensitivity, but the proportion of false positives rises to 66%. Our results are consistent with other studies and suggest that the AMT is a valid instrument for use in screening for dementia in populations similar to the one in this study.

Prevalence of Essential Tremor: A Door-to-Door Survey in Bidasoa, Spain

OBJECTIVES

To assess the prevalence of essential tremor (ET) in two Spanish populations (Irun and Hondarribia, Bidasoa region) and to compare the results with those of similar surveys.

METHODS

The survey included 2,000 participants aged 65 years or older in a door-to-door, two-phase design. ET was defined as postural or kinetic tremor of the head or limbs.

RESULTS

ET prevalence after age adjustment was 4.8% (95% confidence interval, 3.6-6.4). Prevalence increased significantly with age and there were no sex differences.

CONCLUSIONS

The age-adjusted prevalence rate of ET in people 65 years old and older in Bidasoa, Spain, is close to those described in other studies using a similar design and suggest no geographical variation. ET prevalence increases with age and has a similar distribution in males and females.