Age at onset prediction in spinocerebellar ataxia type 3 changes according to population of origin.

BACKGROUND AND PURPOSE: In spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD), the length of CAG repeat expansions in ATXN3 shows an inverse correlation with age at onset (AO). Recently, a formula for predicting AO based on CAG expansion was developed for European carriers. We tested this formula in SCA3/MJD carriers from distinct origins and developed population-specific models to predict AO. METHODS: This was a parametric survival modelling study. RESULTS: The European formula (EF) was tested in 739 independent SCA3/MJD carriers from South Brazil, Taiwan and the Portuguese Azorean islands, and it largely underestimated AO in South Brazilian and Taiwanese test cohorts. This finding challenged the universal use of the EF, leading us to develop and validate population-specific models for AO prediction. Using validation cohorts, we showed that Brazilian and Taiwanese formulas largely outperformed the EF in a population-specific manner. Inversely, the EF was more accurate at predicting AO among Portuguese Azorean patients. Hence, specific prediction models were required for each SCA3/MJD ethnic group. CONCLUSIONS: Our data strongly support the existence of as yet unknown factors that modulate AO in SCA3/MJD in a population-dependent manner, independent of CAG expansion length. The generated models are made available to the scientific community as they can be useful for future studies on SCA3/MJD carriers from distinct geographical origins.

Autonomic dysfunction in hereditary spastic paraplegia type 4.

BACKGROUND AND PURPOSE: SPAST mutations are the most common cause of hereditary spastic paraplegia (SPG4-HSP), which is characterized by progressive lower limb weakness, spasticity and hyperreflexia. There are few studies about non-motor manifestations in this disease and none about autonomic involvement. Therefore, the aim was to determine the frequency and pattern of autonomic complaints in patients with SPG4-HSP, as well as to determine the clinical relevance and the possible factors associated with these manifestations. METHODS: Thirty-four molecularly confirmed SPG4 patients were recruited in a multicenter cross-sectional study, of whom 26 underwent detailed neurophysiological testing (heart rate variability, sympathetic skin response and the Quantitative Sudomotor Axonal Reflex Test). The Scales for Outcomes in Parkinson's Disease - Autonomic Questionnaire (SCOPA-AUT) was applied to quantify the severity of autonomic symptoms. Results were compared with 44 age- and gender-matched healthy controls using non-parametric tests. P values <0.05 were considered significant. RESULTS: In the SPG4-HSP group, there were 18 men with a mean age of 47.7 ± 12.6 years. SCOPA-AUT scores were similar between patients and controls (P = 0.238). Only the urinary domain subscore was significantly higher amongst patients (4 vs. 2.5, P = 0.05). Absent sympathetic skin response in the hands and feet was more frequent amongst patients (20% vs. 0%, P < 0.001, and 64% vs. 0%, P = 0.006, respectively). Quantitative Sudomotor Axonal Reflex Test responses were also smaller throughout all recording regions in the SPG4-HSP group. CONCLUSION: Our results indicate that SPG4-HSP patients have sudomotor dysfunction caused by damaged small post-ganglionic cholinergic fibers. Damage in SPG4-HSP extends to the peripheral nervous system.

Spinocerebellar ataxia type 10: common haplotype and disease progression rate in Peru and Brazil.

BACKGROUND AND PURPOSE: Spinocerebellar ataxia type 10 is a neurodegenerative disorder that is due to an expanded ATTCT repeat tract in the ATXN10 gene. Our aim was to describe clinical characteristics and intragenic haplotypes of patients with spinocerebellar ataxia type 10 from Brazil and Peru. METHODS: Expanded alleles were detected by repeat-primed polymerase chain reaction. Disease progression was measured by the Scale for the Assessment and Rating of Ataxia, and the Neurological Examination Score for Spinocerebellar Ataxias when possible. Haplotypes were constructed based on polymorphic markers within and outside the gene. RESULTS: Thirteen new families were diagnosed (three from Peru). Patients from three Brazilian families diagnosed previously were also reassessed. In total, 25 individuals (16 families) were evaluated. Mean (± SD) age at onset and disease duration were 34.8 ± 10.2 and 12 ± 8 years, respectively. Common findings were ataxia, dysarthria/dysphagia, nystagmus, pyramidal signs, ophthalmoparesis and seizures. No associations were found between clinical findings and geographical origins. Twelve patients living in remote regions were examined only once. In the remaining individuals, the Scale for the Assessment and Rating of Ataxia score, and Neurological Examination Score for Spinocerebellar Ataxias worsened by 0.444 (95% CI, -0.088 to 0.800) and 0.287 (95% CI, -0.061 to 0.635) points/year, respectively. A common haplotype, 19CGGC14, was found in 11/13 of Brazilian and in 1/3 of Peruvian families. CONCLUSIONS: The progression rate was slower than in other spinocerebellar ataxias. A consistently recurrent intragenic haplotype was found, suggesting a common ancestry for most, if not all, patients.

Genetic profile of Brazilian patients with dystrophinopathies.

Different types of mutations in the DMD gene underlie Duchenne muscular dystrophies (DMD) and Becker muscular dystrophies (BMD). Large deletions and duplications are the most frequent causative genetic alterations worldwide, but little is known about DMD/BMD genetic profile in Brazil. Hence, we recruited patients with DMD and BMD from 8 neuromuscular reference centers along the country, and performed a comprehensive molecular investigation that included Multiplex Ligation-dependent Probe Amplification and Next generation sequencing (NGS) analyses. We evaluated 199 patients from 177 unrelated families: 166 with DMD, 32 with BMD and 1 1.5 years old asymptomatic patient with persistent hiperCKemia. Overall, large deletions (58.2%) followed by nonsense mutations (12.4%) and large duplications (11.3%) were the most frequent variants in Brazilian families. Large deletions were less frequent in BMD than in DMD (44.8% vs 60.8%). We identified 19 new DMD variants. Nonsense mutations were significantly more frequent in patients from northeastern region than from southern/southeastern regions of Brazil (27.7% vs 8.5%, P < .05). Genetic profile of Brazilian patients with DMD/BMD is similar to previously reported cohorts, but it is not uniform across the country. This information is important to plan rational clinical care for patients in face of the new coming mutation-specific therapies.

Non-motor symptoms in patients with hereditary spastic paraplegia caused by SPG4 mutations.

BACKGROUND AND PURPOSE: Non-motor manifestations are frequently overlooked in degenerative disorders and little is known about their frequency and clinical relevance in SPG4 hereditary spastic paraplegia (SPG4-HSP). METHODS: Thirty patients with SPG4-HSP and 30 healthy controls answered the Modified Fatigue Impact Scale, Epworth Sleepiness Scale, Brief Pain Inventory and Beck Depression Inventory. Student's t test was used to compare groups and linear regression was used to assess correlations. RESULTS: Patients had higher fatigue scores than controls (31.0 ± 16.5 vs. 14.5 ± 16.0, P = 0.002) as well as pain (3.4 ± 2.7 vs. 1.0 ± 1.6, P = 0.001) and depression (12.7 ± 8.9 vs. 4.4 ± 3.8, P < 0.001, respectively). Fatigue was associated with depression and possibly with disease severity (P = 0.008 and 0.07, respectively). CONCLUSIONS: Fatigue, pain and depression are frequent and often severe manifestations in patients with SPG4-HSP.

Huntington disease and Huntington disease-like in a case series from Brazil.

The aim of this study was to identify the relative frequency of Huntington's disease (HD) and HD-like (HDL) disorders HDL1, HDL2, spinocerebellar ataxia type 2 (SCA2), SCA17, dentatorubral-pallidoluysian degeneration (DRPLA), benign hereditary chorea, neuroferritinopathy and chorea-acanthocytosis (CHAC), in a series of Brazilian families. Patients were recruited in seven centers if they or their relatives presented at least chorea, besides other findings. Molecular studies of HTT, ATXN2, TBP, ATN1, JPH3, FTL, NKX2-1/TITF1 and VPS13A genes were performed. A total of 104 families were ascertained from 2001 to 2012: 71 families from South, 25 from Southeast and 8 from Northeast Brazil. There were 93 HD, 4 HDL2 and 1 SCA2 families. Eleven of 104 index cases did not have a family history: 10 with HD. Clinical characteristics were similar between HD and non-HD cases. In HD, the median expanded (CAG)n (range) was 44 (40-81) units; R(2) between expanded HTT and age-at-onset (AO) was 0.55 (p=0.0001, Pearson). HDL2 was found in Rio de Janeiro (2 of 9 families) and Rio Grande do Sul states (2 of 68 families). We detected HD in 89.4%, HDL2 in 3.8% and SCA2 in 1% of 104 Brazilian families. There were no cases of HDL1, SCA17, DRPLA, neuroferritinopathy, benign hereditary chorea or CHAC. Only six families (5.8%) remained without diagnosis.

Occupational therapy in spinocerebellar ataxia type 3: an open-label trial

Occupational therapy (OT) is a profession concerned with promoting health and well-being through occupation, by enabling handicapped people to participate in the activities of everyday life. OT is part of the clinical rehabilitation of progressive genetic neurodegenerative diseases such as spinocerebellar ataxias; however, its effects have never been determined in these diseases. Our aim was to investigate the effect of OT on both physical disabilities and depressive symptoms of spinocerebellar ataxia type 3 (SCA3) patients. Genomically diagnosed SCA3 patients older than 18 years were invited to participate in the study. Disability, as evaluated by functional independence measurement and Barthel incapacitation score, Hamilton Rating Scale for Depression, and World Health Organization Quality of Life questionnaire (WHOQOL-BREF), was determined at baseline and after 3 and 6 months of treatment. Twenty-six patients agreed to participate in the study. All were treated because OT prevents blinding of a control group. Fifteen sessions of rehabilitative OT were applied over a period of 6 months. Difficult access to food, clothing, personal hygiene, and leisure were some of the main disabilities focused by these patients. After this treatment, disability scores and quality of life were stable, and the Hamilton scores for depression improved. Since no medication was started up to 6 months before or during OT, this improvement was related to our intervention. No association was found between these endpoints and a CAG tract of the MJD1 gene (CAGn), age, age of onset, or neurological scores at baseline (Spearman test). Although the possibly temporary stabilization of the downhill disabilities as an effect of OT remains to be established, its clear effect on depressive symptoms confirms the recommendation of OT to any patient with SCA3 or spinocerebellar ataxia.

Occupational therapy in spinocerebellar ataxia type 3: an open-label trial.

Occupational therapy (OT) is a profession concerned with promoting health and well-being through occupation, by enabling handicapped people to participate in the activities of everyday life. OT is part of the clinical rehabilitation of progressive genetic neurodegenerative diseases such as spinocerebellar ataxias; however, its effects have never been determined in these diseases. Our aim was to investigate the effect of OT on both physical disabilities and depressive symptoms of spinocerebellar ataxia type 3 (SCA3) patients. Genomically diagnosed SCA3 patients older than 18 years were invited to participate in the study. Disability, as evaluated by functional independence measurement and Barthel incapacitation score, Hamilton Rating Scale for Depression, and World Health Organization Quality of Life questionnaire (WHOQOL-BREF), was determined at baseline and after 3 and 6 months of treatment. Twenty-six patients agreed to participate in the study. All were treated because OT prevents blinding of a control group. Fifteen sessions of rehabilitative OT were applied over a period of 6 months. Difficult access to food, clothing, personal hygiene, and leisure were some of the main disabilities focused by these patients. After this treatment, disability scores and quality of life were stable, and the Hamilton scores for depression improved. Since no medication was started up to 6 months before or during OT, this improvement was related to our intervention. No association was found between these endpoints and a CAG tract of the MJD1 gene (CAGn), age, age of onset, or neurological scores at baseline (Spearman test). Although the possibly temporary stabilization of the downhill disabilities as an effect of OT remains to be established, its clear effect on depressive symptoms confirms the recommendation of OT to any patient with SCA3 or spinocerebellar ataxia.

A neurological examination score for the assessment of spinocerebellar ataxia 3 (SCA3).

Spinocerebellar ataxias (SCAs) are characterized by a heterogeneous set of clinical manifestations. Our aims were to assess the neurological features of SCA3, and to describe and test the feasibility, reliability, and validity of a comprehensive Neurological Examination Score for Spinocerebellar Ataxia (NESSCA). The NESSCA was administered to molecularly diagnosed SCA3 patients at an outpatient neurogenetics clinic. The scale, based on the standardized neurological examination, consisted of 18 items that yielded a total score ranging from 0 to 40. The score's interrater reliability and internal consistency were investigated, and a principal components analysis and a correlation with external measures were performed. Ninety-nine individuals were evaluated. Interrater reliability ranged from 0.8 to 1 across individual items (P < 0.001); internal consistency, indicated by Cronbach's alpha, was 0.77. NESSCA scores were significantly correlated with measures of disease severity: disease stage (rho = 0.76, P < 0.001), duration (rho = 0.56, P < 0.001), and length of CAG repeat (rho = 0.30, P < 0.05). NESSCA was a reliable measure for the assessment of distinct neurological deficits in SCA3 patients. Global scores correlated with all external variables tested, showing NESSCA to be a comprehensive measure of disease severity that is both clinically useful and scientifically valid.