Reliability and validity of the International Cooperative Ataxia Rating Scale: a study in 156 spinocerebellar ataxia patients.

To evaluate the efficacy of treatments in spinocerebellar ataxias (SCAs), appropriate clinical scales are required. This study evaluated metric properties of the International Cooperative Ataxia Rating Scale (ICARS) in 156 SCA patients and 8 controls. ICARS was found to be a reliable scale satisfying accepted criteria for interrater reliability, test-retest reliability, and internal consistency. Although validity testing was limited, we found evidence of validity of ICARS when ataxia disease stages and Barthel index were used as external criteria. On the other hand, our study revealed two major problems associated with the use of ICARS. First, the redundant and overlapping nature of several items gave rise to a considerable number of contradictory ratings. Second, a factorial analysis showed that the rating results were determined by four different factors that did not coincide with the ICARS subscales, thus questioning the justification of ICARS subscore analysis in clinical trials.     

Usefulness of the Scale for Assessment and Rating of Ataxia (SARA)

In this study, we examined the usefulness and validity of the Scale for the Assessment and Rating of Ataxia (SARA) in assessing cerebellar ataxia in 27 patients with spinocerebellar degeneration. The inter-rater reliability of the SARA scores between the two neurologists was high. The scores on SARA correlated significantly with the Barthel index and scores on the International Cooperative Ataxia Rating Scale (ICARS). Scores on ICARS and SARA did not correlate with the total length traveled (TLT) or the root mean square area (RMS) of body sways measured by body stabilometry. The time required to examine each patient for SARA was approximately 4 min, one-third the time required for ICARS. Our results indicate that SARA is useful for the evaluation of cerebellar ataxic patients in daily examinations and that body sway analysis by stabilometry is influenced by factors other than cerebellar ataxia, such as muscle weakness, which should be taken into account when body sway analysis is used to evaluate the severity of cerebellar ataxia.     

Quantitative evaluation of balance in patients with spinocerebellar ataxia type 1: A case control study

ObjectiveQuantitative assessment of balance in spinocerebellar ataxia type 1 (SCA1).BackgroundEvaluation of balance in degenerative ataxias is often clinical and subject to bias. Quantification of balance is crucial for evaluating the efficacy of therapeutic and rehabilitative interventions.MethodsThe subjects were 20 patients (males: 14, females: 6) with genetically positive SCA1 and 20 age and gender matched healthy subjects. Ataxia was rated using the International Cooperative Ataxia Rating Scale (ICARS). Balance was assessed by dynamic posturography (Biodex, USA) which included: (a) ability to control balance in all directions (overall balance index, OBI), front to back (anterior–posterior index, API) and side-to-side (medio–lateral index, MLI); and (b) the limits of stability (LOS) in all directions. Balance index was considered abnormal if the actual value exceeded the predictive value.ResultsImpaired balance was found in 80% of patients (all indices in 35%, OBI + API in 25%, only OBI in 15%, and OBI + MLI in 5%). Compared to controls, SCA1 patients had significantly higher balance indices and lower LOS scores. Unlike in controls, the mean value of API was significantly higher than MLI in SCA1. LOS was found to the best predictor of balance abnormality. In patients, all balance indices had significant positive correlations with ICARS, static score of ICARS, body weight, severity and duration of illness, but not with the CAG repeat length.ConclusionsPatients with SCA1 had global impairment of balance, with greater instability in anterior–posterior than medio–lateral directions. Apart from severity and duration of illness, body weight was detriment to maintenance of balance in SCA1. This information may be useful in planning balance rehabilitation in SCA.     

脊髓小脑共济失调12型患者认知功能障碍的研究

目的探讨脊髓小脑共济失调(SCA)12型患者是否存在认知功能障碍及其影响因素。方法采用蒙特利尔认知评估量表(MoCA)、简易精神状态检查量表(MMSE)对5例SCA12型患者(SCA12型组)及13名健康体检者(正常对照组)进行认知功能评估;采用国际协作共济失调评估量表(ICARS)进行共济失调严重程度评分。结果 MoCA评分结果显示,SCA12型组存在认知功能障碍5例(100%),正常对照组存在认知功能障碍10例(77%)。MMSE评分结果显示,SCA12型组存在认知功能障碍2例(40%),正常对照组存在认知功能障碍1例(7.7%)。SCA12型组MoCA和MMSE评分明显低于正常对照组(均P<0.05)。SCA12型组ICARS评分为23～75分,平均(42.6±21.0)分。正常对照组均无共济失调。Spearmans相关性分析显示,SCA12型患者MMSE评分与病程呈负相关(r=-0.894,P=0.041);MoCA抽象功能得分与病程呈负相关(r=-0.884,P=0.047)。结论 SCA12型患者可并发认知功能障碍,这可能与其病程较长有关。     

Topographic brain mapping of the international cooperative ataxia rating scale

The International Cooperative Ataxia Rating Scale (ICARS) is a 100-point semiquantitative scale designed primarily to assess cerebellar dysfunction. However, little is known of the metric properties of this scale. We assessed the ICARS by rating the severity of cerebellar dysfunction in 27 patients with spinocerebellar ataxias (SCA), three patients with sporadic olivopontocerebellar ataxia and 24 healthy control subjects. [(18)F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) study was also performed on each subject. The statistical parametric mapping analyses revealed a significant correlation between the ICARS scores and functional impairment of the frontal regions within SCA patients. The glucose metabolism in the cerebellum, thalamus and caudate nucleus had significant differences between SCA patients and healthy control subjects. The results suggested that the clinical severity of SCA patients correlated with the functional impairment in the frontal regions, the targets of cerebellar efferent projections.     

新疆地区脊髓小脑共济失调2型患者临床表型相关分析

目的分析新疆地区脊髓小脑共济失调2型(SCA2)患者临床表型。方法对根据Harding诊断标准考虑为脊髓小脑共济失调(SCAs)的患者进行神经系统查体,通过国际协作共济失调等级评分量表(ICARS)、简易智力状态量表(MMSE)进行共济失调严重程度及认知功能的初步评估。用酚氯仿法提取基因组DNA,采用PCR对患者进行SCAs亚型分型。对1例SCA2患者进行克隆后测序。结果发现了9例SCA2患者。1例SCA2患者测序结果为CAG重复47次。该患者以震颤起病,临床表现主要为帕金森综合征,病程6年,ICARS评分10分。4名患者以步态失调起病,病程在2~4年,ICARS评分在15~26分。结论根据临床表现可初步诊断脊髓小脑共济失调,SCA2临床表现存在异质性,故确定诊断依赖于基因诊断。以帕金森综合征表现为主的SCA2型患者共济失调症状发展较缓慢。     

Gait Pattern in Inherited Cerebellar Ataxias

Our aim was to perform a comprehensive analysis of the global and segmental features of gait in patients with genetically confirmed inherited ataxias. Sixteen patients with autosomal dominant (spinocerebellar ataxia, SCA1 or 2) or recessive (Friedreich's ataxia, FRDA) ataxia were studied. We used a motion analysis system to record gait kinematic and kinetic data. We measured the mean values of global (time-distance parameters, COM displacement, support moment) and segmental gait parameters (joint displacement and inter-joint coordination), as both discrete and continuous variables, and their variability and correlations with International Cooperative Ataxia Rating Scale (ICARS) scores. We found a marked difference in all global gait parameters between the ataxic patients and the controls and close correlations between longer stride and stance duration and lower gait, posture and total ICARS scores. The only difference between the two patient groups was a shorter step length in the FRDA patients. As regards the segmental features, we found a significantly different waveform shape for all continuous kinematic and kinetic measures between the ataxic patients and the healthy controls, but only minor differences for the discrete measures. Intersegmental coordination evaluated using the continuous relative phase method revealed an irregular alternating joint behaviour without clear evidence of the synchronous pattern of alternating proximal/distal joint seen in healthy subjects. For almost all gait parameters we observed a markedly higher intra-subject variability in the ataxic patients versus the controls, which was strongly related to the clinical ICARS scores. Patients with chronic, progressive inherited ataxias lose the ability to "stabilize" a walking pattern that can be repeated over time. The most peculiar aspect of the gait of inherited ataxia patients, regardless the different genetic forms, seems to be the presence of increased variability of all global and segmental parameters rather than an invariant abnormal gait pattern.     

Inventory of Non-Ataxia Signs (INAS): Validation of a New Clinical Assessment Instrument

Although ataxia is by definition the prominent symptom of ataxia disorders, there are various neurological signs that may accompany ataxia in affected patients. Reliable and quantitative assessment of these signs is important because they contribute to disability, but may also interfere with ataxia. Therefore we devised the Inventory of Non-Ataxia Signs (INAS), a list of neurological signs that allows determining the presence and severity of non-ataxia signs in a standardized way. INAS underwent a rigorous validation procedure that involved a trial of 140 patients with spinocerebellar ataxia (SCA) for testing of inter-rater reliability and another trial of 28 SCA patients to assess short-term intra-rater reliability. In addition, data of the ongoing EUROSCA natural history study were used to determine the reproducibility, responsiveness and validity of INAS. Inter-rater reliability and short-term test–retest reliability was high, both for the total count and for most of the items. However, measures of responsiveness, such as the smallest detectable change and the clinically important change were not satisfactory. In addition, INAS did not differentiate between subjects that were subjectively stable and those that worsened in the 2-year observation period. In summary, INAS and INAS count showed good reproducibility, but unsatisfactory responsiveness. The present analysis and published data from the EUROSCA natural history study suggest that INAS is a valid measure of extracerebellar involvement in progressive ataxia disorders. As such, it is useful as a supplement to the measures of ataxia, but not as a primary outcome measure in future interventional trials.     

The international cooperative ataxia rating scale in Machado-Joseph disease. Comparison with the unified multiple system atrophy rating scale.

Our purpose was to evaluate and compare the international cooperative ataxia rating scale (ICARS) and the unified multiple system atrophy rating scale (UMSARS) in patients with Machado-Joseph disease (MJD). We assessed 52 consecutive subjects with MJD using each scale. Both scales had adequate internal consistency (alpha > 0.90), except for the oculomotor (OD) subscore (alpha = 0.08). Patients with dystonia had the highest scores in both scales, and symptoms other than ataxia clearly confounded the total ICARS score. There was a very strong correlation between the ICARS and UMSARS-II (motor function), and the correlations between the ICARS and UMSARS-I (r = 0.79) (history) and UMSARS-IV (r = 0.69) (disability) were also statistically significant. We found no significant changes in scores after a mean interval of 7.7 months, although there was after a mean interval of 13.3 months. We conclude that the total ICARS score is a reliable method for longitudinal evaluation of ataxia in MJD, but a disease specific scale should be developed.     

Spinocerebellar ataxia type 1 in Russia

Spinocerebellar ataxia type 1 (SCA1) is one form of autosomal dominant cerebellar ataxia (ADCA) caused by trinucleotide (CAG) repeat expansion within a mutant gene. We investigated 25 patients from 15 Russian ADCA families for SCA1 mutation and found an expanded CAG repeat in 5 families. Mutant chromosomes contained 41–51 CAG repeats (mean 46.1, SD 3.1), and normal chromosomes displayed 21–27 repeat units (mean 24.7, SD 1.3). Progressive cerebellar ataxia in our series of SCA1 patients was very commonly associated with dysarthria (in all cases) and pyramidal signs (in 10 of 11 cases). In three patients from one family we found optic atrophy, which has never been described before in genetically proven cases of SCA1. We observed no specific clinical features distinguishing SCA1 from non-SCA1 patients. In contrast to the high frequency of SCA1 in our series, we found no patients with Machado-Joseph disease, another form of ADCA caused by expanded CAG repeat.     

Principal Component Analysis of Cerebellar Shape on MRI Separates SCA Types 2 and 6 into Two Archetypal Modes of Degeneration

Although ??cerebellar ataxia?? is often used in reference to a disease process, presumably there are different underlying pathogenetic mechanisms for different subtypes. Indeed, spinocerebellar ataxia (SCA) types 2 and 6 demonstrate complementary phenotypes, thus predicting a different anatomic pattern of degeneration. Here, we show that an unsupervised classification method, based on principal component analysis (PCA) of cerebellar shape characteristics, can be used to separate SCA2 and SCA6 into two classes, which may represent disease-specific archetypes. Patients with SCA2 (n?=?11) and SCA6 (n?=?7) were compared against controls (n?=?15) using PCA to classify cerebellar anatomic shape characteristics. Within the first three principal components, SCA2 and SCA6 differed from controls and from each other. In a secondary analysis, we studied five additional subjects and found that these patients were consistent with the previously defined archetypal clusters of clinical and anatomical characteristics. Secondary analysis of five subjects with related diagnoses showed that disease groups that were clinically and pathophysiologically similar also shared similar anatomic characteristics. Specifically, Archetype #1 consisted of SCA3 (n?=?1) and SCA2, suggesting that cerebellar syndromes accompanied by atrophy of the pons may be associated with a characteristic pattern of cerebellar neurodegeneration. In comparison, Archetype #2 was comprised of disease groups with pure cerebellar atrophy (episodic ataxia type 2 (n?=?1), idiopathic late-onset cerebellar ataxias (n?=?3), and SCA6). This suggests that cerebellar shape analysis could aid in discriminating between different pathologies. Our findings further suggest that magnetic resonance imaging is a promising imaging biomarker that could aid in the diagnosis and therapeutic management in patients with cerebellar syndromes.     

Urine levels of the polyglutamine ataxin-3 protein are elevated in patients with spinocerebellar ataxia type 3

IntroductionAccumulation of polyglutamine (polyQ) ataxin-3 (ATXN3) contributes to the pathobiology of spinocerebellar ataxia type 3 (SCA3). Recently, we showed that polyQ ATXN3 is elevated in the plasma and cerebrospinal fluid (CSF) of SCA3 patients, and has the potential to serve as a biological marker for this disease [1]. Based on these findings, we investigated whether polyQ ATXN3 can also be detected in urine samples from SCA3 patients.MethodsWe analyzed urine samples from 30 SCA3 subjects (including one pre-symptomatic subject), 35 subjects with other forms of ataxia, and 37 healthy controls. To quantify polyQ ATXN3 protein levels, we used our previously developed immunoassay.ResultsPolyQ ATXN3 can be detected in the urine of SCA3 patients, but not in urine samples from healthy controls or other forms of ataxia. There was a significant statistical association between polyQ ATXN3 levels in urine samples and those in plasma. Further, the levels of polyQ ATXN3 urine associated with an earlier age of SCA3 disease onset.ConclusionAs clinical trials for SCA3 advance, urine polyQ ATXN3 protein has potential to be a useful, non-invasive and inexpensive biomarker for SCA3.     

Cognitive impairment in spinocerebellar ataxia type 12

IntroductionCognitive impairment has now been recognised to be present in patients with several of spinocerebellar ataxias (SCAs). Cognitive impairment in patients with spinocerebellar ataxia type 12 has not been evaluated.ObjectiveTo evaluate the cognitive impairment in patients diagnosed with spinocerebellar ataxia type 12 (SCA12).MethodsWe conducted a cross sectional study and enrolled 30 (20 male and 10 female) genetically confirmed SCA12 patients and 30 healthy, age, gender and education matched individuals as controls. Cognitive domains were tested using a battery of validated neurocognitive tests.ResultMean age of patients was 51.6 ± 8.0 years and mean disease duration was 5.3 ± 3.0 years. Mean International Cooperative Ataxia Rating Scale (ICARS) score was 29.8 ± 12.5. SCA 12 patients scored significantly lower than controls in executive function and new learning ability. Other tested cognitive domains were also affected but did not reach statistical significance. Age, age at onset, severity of ataxia, disease duration and CAG repeat length did not correlate with cognitive impairment.ConclusionCognitive impairment is a part of the spectrum of SCA12 and is characterized by dysfunction in executive function and new learning ability even early in the course of disease.     

Double-blind crossover study of branched-chain amino acid therapy in patients with spinocerebellar degeneration

To determine whether treatment with branched-chain amino acids (BCAA) can improve the condition of patients with ataxia, a double-blind crossover study of BCAA therapy was performed in 16 patients with spinocerebellar degeneration (SCD). The patients were treated with BCAA in oral doses of 1.5, 3.0, or 6.0 g or with placebo daily for 4 weeks in each study phase. The order of treatment phases (placebo or BCAA) was assigned randomly. An International Cooperative Ataxia Rating Scale (ICARS) was used to quantify the severity of symptoms of SCD. The mean ICARS score improved significantly with BCAA treatment compared with the mean pretreatment score (p<0.01). In addition, the improvement in the mean global ICARS score was significant in the middle-dose group compared with that in the placebo group (p<0.02). The estimated improvement in kinetic functions compared with pretreatment (p<0.01) was significant after treatment with BCAA, 1.5 and 3.0 g. All of the responders manifested predominantly cerebellar symptoms, especially those with spinocerebellar ataxia type 6 (SCA6). Thus, treatment with BCAA may be effective in patients with the cerebellar form of SCD.     

A new sulcus-corrected approach for assessing cerebellar volume in spinocerebellar ataxia

Precise volumetry of the cerebellum still remains challenging, due to thin sulci and gyri. We present a new fast and reliable sulcus-corrected approach for quantitative assessment of cerebellar atrophy, evaluated on patients with spinocerebellar ataxia (SCA). Thin-sliced T1-weighted magnetic resonance images (MPRAGE) were acquired in 11 genetically confirmed SCA6 patients and in a group of age-matched control subjects (n = 14). Post-processing involves a morphological image segmentation pipeline as a basis for a sulcus-corrected cerebellar volume measurement. Cerebellar volumes and intra-rater, inter-rater and scan-rescan reproducibility were quantified. Reliability of the measurements was validated using an anatomical preparation of the cerebellum. Repeatability coefficients (RC: intra-rater/inter-rater/scan-rescan) of the method were 1.07%/1.11%/1.35%. Absolute cerebellar volumes showed good agreement with the actual volume of the anatomical preparation. The cerebellar volume of the SCA 6 was 96.3 ± 12.1 ml (mean ± S.D.), which was significantly lower than the results of the corresponding control groups. The cerebellar volume correlated significantly to clinical dysfunction in SCA6. This is the first study to demonstrate the feasibility of a new sulcus-corrected approach to assess cerebellar volume. In contrast to currently used methods, this new approach may be more sensitive even to small atrophic changes affecting sulcal widening.     

Reliability and validity of ICARS in focal cerebellar lesions.

To evaluate the therapies for cerebellar diseases appropriate neurological assessment methods to measure severity of ataxia are required. Reliability and validity of the semiquantitative International Cooperative Ataxia Rating Scale (ICARS) has recently been examined in patients with degenerative ataxias. We evaluated reliability (internal consistency), criterion-related validity and internal construct validity of ICARS for the first time in patients with focal cerebellar lesions (68 patients with surgical lesions and 68 patients with ischemic lesions). For comparison 45 patients with degenerative cerebellar ataxia were included. We found an excellent Cronbach's alpha as a measurement for internal consistency which was independent from underlying disease. Criterion-related validity was high. Total ICARS score mirrored clearly the immediate postsurgical worsening and the improvement during the first 3 months after focal surgical and ischemic lesions, whereas in chronic state of focal and degenerative cerebellar disorders ICARS score remained nearly unchanged. Principal component analysis in patients with focal lesions revealed five distinct and clinically meaningful factors which corresponded to the four ICARS subscores and reflected the laterality of kinetic functions. In degenerative disorders, however, the items for the subscore "kinetic function" loaded to more than one factor. Total ICARS score seems to be a useful and valid measurement to describe the time course of ataxia in patients with focal and degenerative disorders affecting primarily the cerebellum. Validity of subscores however is good in focal, but not in degenerative disorders.     

Challenges in sleep stage R scoring in patients with autosomal dominant spinocerebellar ataxias (SCA1, SCA2 and SCA3) and oculomotor abnormalities: a whole night polysomnographic evaluation

ObjectivesSpinocerebellar ataxias are progressive neurodegenerative disorders characterized by progressive cerebellar features with additional neuro-axis involvement. Oculomotor abnormality is one of the most frequent manifestations. This study was done to assess the polysomnographic abnormalities in patients with Spinocerebellar ataxia (SCA1, SCA2 and SCA3) and also to evaluate whether oculomotor abnormalities interfere with sleep stage R scoring.MethodsThe study was carried out using 36 genetically positive SCA patients. All patients underwent neurological examination with special focus on oculomotor function (optokinetic nystagmus-OKN and extraocular movement restriction-EOM). The sleep quality was measured with Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Disease severity was assessed with International Cooperative Ataxia Rating Scale (ICARS). All the patients underwent over-night video-polysomnography (VPSG).ResultsOut of 36 patients studied, the data of 34 patients [SCA1 (n = 12), SCA2 (n = 13), SCA3 (n = 9)] were used for final analysis. Patients from SCA1, SCA2, and SCA3 category did not show significant differences in age and diseases severity (ICARS). All patients had vertical OKN impairment. Oculomotor impairment was higher in SCA2 patients. Sleep macro-architecture analysis showed absent stage R sleep, predominantly in SCA2 (69%) followed by SCA3 (44%) and SCA1 (8%). Patients showed a strong negative correlation of stage R sleep percentage with disease severity and oculomotor dysfunction.ConclusionVoluntary saccadic eye movement velocity and rapid eye movements (REMs) in sleep are strongly correlated. The more severe the saccadic velocity impairment, the less likely was it to generate REMs (rapid eye movements) during stage R. Accordingly 69% of SCA2 patients with severe occulomotor impairments showed absent stage R as per the AASM sleep scoring. We presume that the impaired REMs generation in sleep could be due to oculomotor abnormality and has resulted in spuriously low or absent stage R sleep percentage in SCA patients with conventional VPSG scoring rules. The present study recommends the modification of AASM scoring rules for stage R in patients with oculomotor abnormalities.     

Spinocerebellar ataxia type 8 in Scotland: genetic and clinical features in seven unrelated cases and a review of published reports

OBJECTIVES: To establish whether the DNA expansion linked to spinocerebellar ataxia type 8 (SCA 8) is associated with ataxia in Scotland; to clarify the range of associated clinical phenotypes; and to compare the findings with previous reports. METHODS: DNA was screened from 1190 anonymised controls, 137 subjects who had tested negative for Huntington's disease, 176 with schizophrenia, and 173 with undiagnosed ataxia. Five unrelated ataxic patients with the SCA 8 expansion and a sixth identified subsequently had clinical and psychometric assessment; the clinical features were available in a seventh. A systematic search for other reports of SCA 8 was undertaken. RESULTS: Over 98% of SCA 8 CTA/CTG repeat lengths fell between 14 and 40. Repeat lengths over 91 were observed in three healthy controls (0.12%), two patients with suspected Huntington's disease (0.73%), and six ataxic subjects (1.74%; p<0.0005 v healthy controls). Repeat lengths over 100 occurred in five ataxic subjects but in only one control. All seven symptomatic subjects with the SCA 8 expansion had a cerebellar syndrome; four had upper motor neurone signs; and 5/6 assessed had cognitive complaints. There was personality change in two and mood disturbance in three. In published reports, SCA 8 repeat lengths over 91 occurred in approximately 0.5% of the healthy population but were over-represented among ataxic patients (3.4%; p<0.0001). The predominant clinical phenotype was cerebellar, with pyramidal signs in 50%, and neuropsychiatric features in some cases. CONCLUSIONS: SCA 8 expansion is a risk factor for a cerebellar syndrome, often associated with upper motor neurone and neuropsychiatric features. The expansion occurs unexpectedly often in the general population.     

Degree of cerebellar ataxia correlates with three-dimensional mri-based cerebellar volume in pure cerebellar degeneration

The aim of the present study was to compare the severity of cerebellar ataxia as measured by the International Cooperative Ataxia Rating Scale (ICARS) by Trouillas et al. [ J Neurol Sci 1997;145:205-211] with the cerebellar volume in chronic cerebellar disease. Fifteen patients with pure cerebellar degeneration were investigated. Seven patients suffered from spinocerebellar ataxia type 6, 5 from idiopathic late-onset cerebellar ataxia, 2 from autosomal dominant cerebellar ataxia type III and 1 from episodic ataxia type 2. Volumetric analysis was based on individual three-dimensional MR images. Total ICARS score significantly inversely correlated with the cerebellar volume (r = -0.805, p < 0.0001), correlations between ICARS subscores and cerebellar volume were significant for upper and lower limb ataxia, ataxia of posture and gait, and dysarthria, but not for the oculomotor subscore. The results suggest that the degree of cerebellar atrophy in pure cerebellar degenerative disorders is accompanied by comparable functional impairment (i.e. degree of cerebellar ataxia).