Plasma cytokines profile in patients with Alzheimer's and Parkinson's Disease: a comparative study in terms of inflammation.

BACKGROUND: Neurodegenerative disorders such as Alzheimer's and Parkinson's disease inflict economic and health burdens on societies. Alzheimer's disease (AD), the most prevalent form of dementia, is accompanied by progressive degradation of memory, decision-making, and judgment. Parkinson's disease (PD) is characterized by resting tremor, rigidity, bradykinesia, and loss of balance. Extensive research has pinpointed inflammation as a cause of the onset and progression of both diseases. However, it has not been confirmed which one is more formidable in terms of inflammation. METHODS: To assess the extent of inflammation that is implicated in AD and PD and answer the question of which one is more inflammatory, serum levels of inflammatory biomarkers, including cytokines, chemokines, and prostaglandin E2 (PEG2), were measured in AD and PD patients as well as a healthy group. RESULTS: Our results showed a significant increase in IL-1α, IL-1ß, IL-4, IL-6, IL-10, IL-12p70, IP-10, MCP-1, PEG2, and TNF-α in AD and PD patients compared with the control. Interestingly, IFN-γ did not manifest any significant difference in AD or PD patients compared with the control. CONCLUSION: As a hallmark of our results, it could be inferred that inflammation, as the underlying etiological cause, plays a more crucial role in PD compared with AD. Based on our results, it is proposed that anti-inflammatory remedies would be putatively more effective in PD rather than AD.

Consensus guidelines for botulinum toxin therapy: general algorithms and dosing tables for dystonia and spasticity.

Botulinum toxin (BT) therapy is a complex and highly individualised therapy defined by treatment algorithms and injection schemes describing its target muscles and their dosing. Various consensus guidelines have tried to standardise and to improve BT therapy. We wanted to update and improve consensus guidelines by: (1) Acknowledging recent advances of treatment algorithms. (2) Basing dosing tables on statistical analyses of real-life treatment data of 1831 BT injections in 36 different target muscles in 420 dystonia patients and 1593 BT injections in 31 different target muscles in 240 spasticity patients. (3) Providing more detailed dosing data including typical doses, dose variabilities, and dosing limits. (4) Including total doses and target muscle selections for typical clinical entities thus adapting dosing to different aetiologies and pathophysiologies. (5) In addition, providing a brief and concise review of the clinical entity treated together with general principles of its BT therapy. For this, we collaborated with IAB-Interdisciplinary Working Group for Movement Disorders which invited an international panel of experts for the support.

A new postural stability-indicator to predict the level of fear of falling in Parkinson's disease patients.

BACKGROUND: Fear of falling (FoF) is defined as a lasting concern about falling that causes a person to limit or even stop the daily activities that he/she is capable of. Seventy percent of Parkinson's disease (PD) patients report activity limitations due to FoF. Timely identification of FoF is critical to prevent its additional adverse effects on the quality of life. Self-report questionnaires are commonly used to evaluate the FoF, which may be prone to human error. OBJECTIVES: In this study, we attempted to identify a new postural stability-indicator to objectively predict the intensity of FoF and its related behavior(s) in PD patients. METHODS: Thirty-eight PD patients participated in the study (mean age, 61.2 years), among whom 10 (26.32%) were identified with low FoF and the rest (73.68%) with high FoF, based on Falls Efficacy Scale-International (FES-I). We used a limit of stability task calibrated to each individual and investigated the postural strategies to predict the intensity of FoF. New parameters (FTRis; functional time ratio) were extracted based on the center of pressure presence pattern in different rectangular areas (i = 1, 2, and 3). The task was performed on two heights to investigate FoF-related behavior(s). RESULTS: FTR1/2 (the ratio between FTR1 and FTR2) was strongly correlated with the FES-I (r = - 0.63, p < 0.001), Pull test (r = - 0.65, p < 0.001), Timed Up and Go test (r = - 0.57, p < 0.001), and Berg Balance Scale (r = 0.62, p < 0.001). The model of FTR1/2 was identified as a best-fitting model to predicting the intensity of FoF in PD participants (sensitivity = 96.43%, specificity = 80%), using a threshold level of ≤ 2.83. CONCLUSIONS: Using the proposed assessment technique, we can accurately predict the intensity of FoF in PD patients. Also, the FTR1/2 index can be potentially considered as a mechanical biomarker to sense the FoF-related postural instability in PD patients.

Lee Silverman voice treatment (LSVT) mitigates voice difficulties in mild Parkinson's disease.

Background: Parkinson's disease (PD) is a progressive neurological disorder and many PD patients experience some type of voice and speech disorders during the course of illness. In this study, the aim was to investigate the effect of Lee Silverman voice treatment (LSVT) on improving voice difficulties in patients with mild PD using voice handicap index (VHI). Methods: This interventional study was conducted on 23 PD patients who were randomly divided into 2 groups: a treatment group (PD-T) (n=13) and a no-treatment group (PD-NT) (n=10). Neurologically healthy control (NNC) group consisted of 13 healthy participants who did not suffer from voice and speech problems and were matched with PD group by age (50-65 years), sex, and education. VHI questionnaire was completed a day before the start of LSVT and a day after the treatment fulfillment for the PD-T group; the same time spots were applied for the PD-NT and NNC groups. Statistical analyses were performed using SPSS Statistics 22.0 and significance level was set at 0.05. The multivariate analysis of variance and repeated measure analysis of variance were used for data analysis. Results: PD groups showed a significant weakness in VHI scores before treatment compared to NNC group (p≤ 0.001). The mean of VHI scores for PD-T, PD-NT, and NNC groups before treatment was 44.31±11.23, 43.54±6.10, and 8.15±4.27, respectively. LSVT was successful in improving VHI scores in PD-T group (17.23±5.35, p≤ 0.001). However, no improvement was observed in PD-NT group (44.00±5.88). Conclusion: Improvement in VHI score could be the result of ameliorated self-monitoring and self-regulation created by LSVT.

PTRHD1 (C2orf79) mutations lead to autosomal-recessive intellectual disability and parkinsonism.

INTRODUCTION: Atypical parkinsonism is a neurodegenerative disease that includes diverse neurological and psychiatric manifestations. OBJECTIVES: We aimed to identify the disease-cauisng mutations in a consanguineous family featuring intellectual disability and parkinsonism. METHODS: Full phenotypic characterization, followed by genome-wide single-nucleotide polymorphism genotyping and whole-genome sequencing, was carried out in all available family members. RESULTS: The chromosome, 2p23.3, was identified as the disease-associated locus, and a homozygous PTRHD1 mutation (c.157C>T) was then established as the disease-causing mutation. The pathogenicity of this PTRHD1 mutation was supported by its segregation with the disease status, its location in a functional domain of the encoding protein, as well as its absence in public databases and ethnicity-matched control chromosomes. CONCLUSION: Given the role of 2p23 locus in patients with intellectual disability and the previously reported PTRHD1 mutation (c.155G>A) in patients with parkinsonism and cognitive dysfunction, we concluded that the PTRHD1 mutation identified in this study is likely to be responsible for the phenotypic features of the family under consideration. © 2016 International Parkinson and Movement Disorder Society.

Reliability and validity of the Persian translation of Berg Balance Scale in Parkinson disease.

PURPOSE: Parkinson disease (PD) is one of the common causes of imbalance, and the balance assessment is necessary for treatment and rehabilitation of these patients. The Berg Balance Scale (BBS) has been the main instrument used to evaluate balance impairment. The purpose of this study is to investigate reliability and validity of the Persian translation of BBS in Parkinson disease. METHODS: One hundred PD patients (with mean age of 56.8 ± 15.13 years) were included. Interrater reliability was measured with the Kappa statistics and interclass correlation coefficients. RESULTS: The mean values of the BBS scored by the two evaluators were 47/85 ± 11/09 and 48/03 ± 10/90, respectively. The mean of Kappa coefficient between two examiners was 0.76, which was between 0.38 and 0.93 for various items. The total score recorded by both examiners, interclass correlation coefficient, was 0.99, which is excellent. Cronbach's alpha for Iranian version of BBS was 0.92, which shows the excellent reliability of the questionnaire (0.62-0.9 for all items). CONCLUSION: The Persian version of the BBS has excellent interrater reliability and internal consistency for the assessment of PD patients.

Mutation in ADORA1 identified as likely cause of early-onset parkinsonism and cognitive dysfunction.

BACKGROUND: We aimed to identify the genetic cause of neurological disease in an Iranian family whose manifestations include symptoms of parkinsonism and cognitive dysfunction. METHODS: Clinical data on the patients were gathered by interviews with parents, neurological examinations, and laboratory tests. Genetic analysis was performed by genome-wide single-nucleotide polymorphism homozygosity mapping and exome sequencing. The effect of putative disease-causing mutation was assessed by immunocytochemistry on HEK293 cells and Western blotting on proteins extracted from HEK293 cells transfected with wild-type and mutated genes. RESULTS: Homozygosity mapping and exome sequencing led to identification of a mutation in ADORA1 that causes p.Gly279Ser in the encoded protein, adenosine A1 receptor (A1 R), as the probable cause of disease. The mutation segregated with disease status in the family, affects a highly conserved amino acid, and was absent in 700 controls. CONCLUSIONS: The known biological activities of A1 R in brain functions including its physical interaction with and inhibitory effect on dopamine receptor D1 provide supportive evidence that disruptions of A1 R may result in neurological dysfunction. Also, recent evidence on the related adenosine A2B receptor marks the domain in which the mutation is positioned as important for function. Finally, ADORA1 is located within the Parkinson's disease locus PARK16, which has been identified in several populations. ADORA1 may be the PD susceptibility gene within this locus. The molecular mechanism by which p.Gly279Ser disrupts A1 R function remains unknown, but a quantitative effect on interaction with the dopamine receptor was not shown. © 2016 International Parkinson and Movement Disorder Society.

Mini Nutritional Assessment (MNA) is Rather a Reliable and Valid Instrument to Assess Nutritional Status in Iranian Healthy Adults and Elderly with a Chronic Disease.

This study aimed to evaluate the usefulness of the Mini Nutritional Assessment (MNA) to assess nutritional status of Iranian population and to compare its psychometric properties between patients suffering from a chronic disease, healthy elderly and younger adults. As a group of elderly with a chronic disease, 143 Parkinson's disease (PD) patients and as the control group, 467 healthy persons were enrolled. The Persian-translated version of MNA was filled-up through interviews together with anthropometric measurements. Cronbach's α coefficient of entire MNA was 0.66 and 0.70 in healthy individuals and PD patients, respectively. The total MNA score could significantly discriminate the ones with BMI ≥ 24kg/m(2) in both groups. In general, MNA was a valid and reliable tool for nutritional assessment. We acknowledge study limitations including lack of serum measurements and a selection bias towards mild-to-moderate PD. MNA is a more reliable tool in older healthy individuals and rather younger elderly with PD.

A novel 6-item screening questionnaire for Parkinsonism: validation and comparison between different instruments.

BACKGROUND: Several instruments have been developed to screen Parkinson's disease (PD); yet, there is no consensus on the items, number of questions, and diagnostic accuracy. We aimed to develop a new questionnaire combining the best items with highest validity to screen parkinsonism and to compare its diagnostic value with that of the previous instruments using the same database. METHODS: 157 patients with parkinsonism and 110 healthy controls completed a comprehensive screening questionnaire consisting of 25 items on different PD symptoms used in previous studies. To select the optimal items, clinical utility index (CUI) was calculated and those who met at least good negative utility (CUI ≥0.64) were selected. Receiver operating characteristics (ROC) curves analysis was used to compare the area under the curve (AUC) of different screening instruments. RESULTS: Six items on 'stiffness & rigidity', 'tremor & shaking', 'troublesome buttoning', 'troublesome arm swing', 'feet stuck to floor' and 'slower daily activity' demonstrated good CUI. The new screening instrument had the largest AUC (0.977) compared to other instruments. CONCLUSIONS: We selected a new set of six items to screen parkinsonism, which showed higher diagnostic values compared to the previously developed questionnaires. This screening instrument could be used in population-based PD surveys in poor-resource settings.

Psychometric study of the Persian short-form eight-item Parkinson's disease questionnaire (PDQ-8) to evaluate health related quality of life (HRQoL).

BACKGROUND: To assess validation and reliability of the Persian version of the short-form 8-item Parkinson's disease questionnaire (PDQ-8) and to compare its psychometric properties with that of the long-form questionnaire (PDQ-39) in order to evaluate the health-related quality of life (HRQoL) in patients with Parkinson's disease (PD). METHODS: This cross-sectional study was conducted on 114 non-demented idiopathic PD (IPD) patients consecutively recruited from an outpatient referral movement disorder clinic. Patients were interviewed to fill in the Persian version of PDQ-39 and PDQ-8 questionnaires and clinical examination was performed to measure disease severity indices. RESULTS: The Cronbach's alpha coefficient of the entire PDQ-8 was 0.740 (95% CI: 0.661-0.806). Replacement of PDQ-8 items with other questions with the highest internal consistency within each dimension of the original PDQ-39 did not improve Cronbach's alpha coefficient [0.723 (95% CI: 0.639-0.794)]. The scores from both PDQ-8 and PDQ-39 had significant correlation with the Hoehn & Yahr (rPDQ-8 = 0.376, rPDQ-39 = 0.442), and Schwab & England (rPDQ-8 = -0.503, rPDQ-39 = -0.598) disease severity scales and disease duration (rPDQ-8 = 0.342, rPDQ-39 = 0.396). CONCLUSIONS: Persian version of the short-form PDQ (PDQ-8) was shown to be a valid and reliable instrument to assess disease-specific HRQoL in a PD population when used independently. Although the PDQ-8 items were not necessarily those with the highest internal consistency in the components of PDQ-39, they entirely showed proper psychometric properties especially in mental and behavioral aspects. PDQ-8 is a practical and informative instrument in daily clinical practice where clinicians are in shortage of time and when a validated self-reported brief questionnaire is of value.

Pallidal deep brain stimulation for the treatment of DYT6 dystonia: a case report and review of literature.

Little is known about the results of pallidal deep brain stimulation (DBS) in DYT6 dystonia. This will be the first report of DYT6 dystonia treated with pallidal DBS from Iran. A 21 years old male patient with DYT6 dystonia underwent bilateral deep brain stimulation. The target of DBS was the sensorimotor region of the posteroventral globus pallidus internus (GPi). DBS parameters included an amplitude of 2.7 V, frequency of 160 Hz, and pulse width of 90 µs which were adjusted according to the patient's response 12 months after surgery. Treatment outcome was measured by the patient's Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) score. Before surgery, the patient's BFMDRS score was 32. However, BFMDRS score reduced to 7 at one year follow up after surgery (78% improvement of total score). Dystonic symptoms of extremities and mouth completely resolved. Also speech and swallowing function significantly improved. Although previous observations reported a poor to moderate response in speech, we found DBS as an effective treatment not only for dystonic features, but also for speech improvement of DYT6 dystonia.

Deep brain stimulation of globus pallidus internus for DYT1 positive primary generalized dystonia.

BACKGROUND: Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is recommended as a promising technique for the management of the primary generalized dystonia (PGD) with DYT1 gene mutation. We present the first report of DBS results in Iranian patients with DYT1 positive PGD. METHODS: Nine patients who suffered from severely disabling DYT1 positive PGD consecutively were recruited for the study between 2008 and 2010. The patients underwent bilateral deep brain stimulation of the GPi in a single procedure. The mean follow up duration was 8.8 ± 2.2 months. The efficacy of the intervention was evaluated by comparing pre- and post operative scores of patients with Burke-Fahn-Marsden's dystonia Scale (BFMDS). Statistical analysis was performed using SPSS 11.0 software. RESULTS: Of 9 patients six were female with the mean age of 15.2 ± 5.5 years old (range: 8- 25 years old). The mean for Burke-Fahn-Marsden's Dystonia Rating Scale (BFMDRS) score was 47.22 ± 14.1 before surgery and 12.3 ± 8.2 after follow up, which significantly improved (P=0.0001).The mean stimulation parameters at the last visit were at a frequency of 152.2 ± 32.4 Hz (range 130- 230 Hz), a voltage of 2.6 ± 0.7 V (range 1.1- 4), and a pulse width of 60 µsec. No complication was observed during follow up. CONCLUSION: Bilateral DBS of the GPi has an encouraging result for the management of DYT1 positive PGD and is recommended as a safe technique for the treatment of these patients. Shorter pulse width in stimulation parameters is suggested for DYT1 dystonia patients.

The Sac1 domain of SYNJ1 identified mutated in a family with early-onset progressive Parkinsonism with generalized seizures.

This study aimed to elucidate the genetic causes underlying early-onset Parkinsonism (EOP) in a consanguineous Iranian family. To attain this, homozygosity mapping and whole-exome sequencing were performed. As a result, a homozygous mutation (c.773G>A; p.Arg258Gln) lying within the NH2 -terminal Sac1-like inositol phosphatase domain of polyphosphoinositide phosphatase synaptojanin 1 (SYNJ1), which has been implicated in the regulation of endocytic traffic at synapses, was identified as the disease-segregating mutation. This mutation impaired the phosphatase activity of SYNJ1 against its Sac1 domain substrates in vitro. We concluded that the SYNJ1 mutation identified here is responsible for the EOP phenotype seen in our patients probably due to deficiencies in its phosphatase activity and consequent impairment of its synaptic functions. Our finding not only opens new avenues of investigation in the synaptic dysfunction mechanisms associated with Parkinsonism, but also suggests phosphoinositide metabolism as a novel therapeutic target for Parkinsonism.

Identification of COL6A2 mutations in progressive myoclonus epilepsy syndrome.

In this study, a consanguineous family with progressive myoclonus epilepsy (PME) was clinically examined and molecularly investigated to determine the molecular events causing disease. Since exclusion of known genes indicated that novel genes causing PME still remained unidentified, homozygosity mapping, exome sequencing, as well as validation and disease-segregation analyses were subsequently carried out for both loci and gene identification. To further assure our results, a muscle biopsy and gene expression analyses were additionally performed. As a result, a homozygous, disease-segregating COL6A2 mutation, p.Asp215Asn, absent in a large number of control individuals, including control individuals of Iranian ancestry, was identified in both affected siblings. COL6A2 was shown to be expressed in the human cerebral cortex and muscle biopsy revealed no specific histochemical pathology. We conclude that the COL6A2 p.Asp215Asn mutation is likely to be responsible for PME in this family; however, additional studies are warranted to further establish the pathogenic role of both COL6A2 and the extracellular proteolysis system in the pathogenesis of PME.

PANK2 and C19orf12 mutations are common causes of neurodegeneration with brain iron accumulation.

BACKGROUND: Neurodegeneration with brain iron accumulation (NBIA) constitutes a group of neurodegenerative disorders with pronounced iron deposition in the basal ganglia. PANK2 mutations are the most common cause of these disorders. C19orf12 was recently reported as another causative gene. We present phenotypic data and results of screening of PANK2 and C19orf12 in 11 unrelated Iranian NBIA patients. METHODS: Phenotypic data were obtained by neurologic examination, magnetic resonance imaging, and interviews. Mutation screening of PANK2 and C19orf12 was performed by sequencing. RESULTS: PANK2 and C19orf12 mutations were found in 7 and 4 patients, respectively. Phenotypic comparisons suggest that C19orf12 mutations as compared with PANK2 mutations result in a milder disease course. CONCLUSIONS: Mutations in both PANK2 and C19orf12 contributed significantly to NBIA in the Iranian patients. To the best of our knowledge, this is the first genetic analysis reported on a cohort of NBIA patients from the Middle East.

A study of factors associated with cerebral venous thrombosis.

Cerebral venous thrombosis (CVT) is an uncommon but important cause of stroke. Since there are few number of studies about the factors associated with CVT, we aimed to perform a study on Iranian patients, during a 12-year period (1997-2010) and assessed the risk factors, mortality rate, symptoms and signs, imaging and seasonal distribution. This study was a retrospective cross sectional study conducted in Rasul-e-Akram Hospital of Tehran University of Medical Sciences. The hospital is a referral neurology center for west, south and east parts of the capital city. The patients' data were extracted from the documents and entered to a self-designed checklist including probable risk factors, sequels, involved venous and also demographic characteristics. From 62 patients, 85.5% of the patients were female. Most of the patients were between 25 and 35 years old. Superior sagittal sinus was involved in 35 patients. Generalized seizure in the expired group (7 patients) was significantly more than the alive group (P = 0.017). There was a significant relationship between intracranial hemorrhage and mortality rate and between the site of thrombosis and level of consciousness. There was also a significant relationship between fasting and pregnancy with seizure in these patients. Although most of the patients presented in spring and autumn, majority of the expired cases were reported in autumn. This study can help defining risk factors, symptoms, and predicting risk factors of seizure in patients with CVT. We suggest future studies based on gathering data for meta-analysis.

Restless legs syndrome in Iranian patients with multiple sclerosis.

Restless legs syndrome (RLS) is a common neurological movement disorder that is often seen in multiple sclerosis patients. However, the association between RLS and multiple sclerosis (MS) is still unclear and RLS is not considered as one of the MS symptoms. This study was conducted to assess the frequency of RLS and its associated factors in patients with MS. This was a cross-sectional study conducted during January and April 2010. A total of 205 patients diagnosed with multiple sclerosis (164 females, 41 males, mean age 32.8 ± 8.9 years) were enrolled in the study and underwent a medical history interview and a neurological examination. The diagnosis of RLS was based on International Restless Legs Syndrome Study Group Criteria. 57 patients (27.8%) met the RLS diagnostic criteria. In 90.1% of the patients, the onset of RLS was simultaneous with or followed by MS onset. There was no significant difference between patients with and without RLS in respect of age, gender, disease duration, and MS pattern. There was an increased incidence of leg jerks before sleep in patients with RLS (P = 0.04). In patients suffering from RLS, there is greater complaint of insomnia (P = 0.03). Body mass index, history of anemia, excessive day-time somnolence, consuming caffeine-containing beverages, pregnancy numbers, smoking, and alcohol consumption were not associated with the presence of RLS. This study revealed high prevalence of RLS in MS patients. Screening of RLS in these patients should always be considered to improve management of MS.

Clinical features, DYT1 mutation screening and genotype-phenotype correlation in patients with dystonia from Iran.

OBJECTIVE: To test Iranian patients with primary torsion dystonia to determine the frequency of 904-906 del GAG mutation in the DYT1 (TOR1A) gene and to investigate the genotype-phenotype association for this disease. SUBJECTS AND METHODS: Sixty-three patients with primary dystonia were investigated. DNA was extracted from peripheral blood and these samples were subjected to PCR-sequencing for exon 5 of the DYT1 gene. RESULTS: Of the 63 patients, 10 (15.9%) carried the triplet GAG deletion mutation; this is a high DYT1-positive rate in comparison with other populations and the type of dystonia in this positive group was generalized in all except 1. In our patients, limbs were the most severely involved site at the time of onset and in most cases it developed to generalized form. The majority of DYT1-positive cases showed higher leg onset (5 patients, 62.5%) in comparison with higher arm onset in negative patients (20 patients, 50%). Also, the progression to generalized dystonia in DYT1-positive patients was significantly higher than in DYT1-negative patients. The mean age at onset was 8.6 ± 1.6 years (7-12 years) in DYT1-positive patients, while mean age at onset in patients with no GAG deletion mutation was higher (15.7 ± 11.5 years). CONCLUSIONS: The DYT1 904-906 del GAG mutation is responsible for some of Iranian dystonia patients, and screening for the DYT1 deletion is significant in cases with the generalized type of primary dystonia. Also, patients with leg or arm onset at a younger age are more likely to be DYT1-positive among primary torsion dystonia cases.

Study of chaotic behavior of tremor of some Parkinsonians under deep brain stimulation.

Deep Brain Stimulation, functional neurosurgery for Parkinson's disease treatment, has three parameters: frequency, pulse width, and voltage. They should be selected appropriately to achieve an effective treatment. In this research, we studied some nonlinear dynamics of Parkinsonian tremor under Deep Brain Stimulation. We recorded finger tremor signals of 8 patients at different voltages as data. To study tremor behavior variation at different voltages, we extracted some nonlinear dynamic features of the data. These features were: embedding space, correlation dimension, largest Lyapunov exponent, entropy and variance of embedding space along x, and y axes. We found that the largest Lyapunov exponents were positive and correlation dimensions of data were not integer, and also all embedding spaces at different voltages had attractors. These observations show that the tremor signal has chaotic behaviors. Also, embedding space variance along x, and y axes in all cases and entropy in the most of them had minimum values at highest voltages in comparison with other voltages. We plotted bar graphs of embedding space variances along x, and y axes at every patient's recorded voltages. A reduction procedure was seen after a threshold in all graphs. As a result, all the chaotic features change with the voltage variation. In the future, it could be possible to select the optimum stimulation voltages by using chaotic features of tremor.

Relation between Voice Handicap Index (VHI) and disease severity in Iranian patients with Parkinson's disease.

BACKGROUND: One third of patients with Parkinson's disease (PD) have mentioned "dysphonia" as their most debilitating communication deficit. Patient-based measurements, such as Voice Handicap Index (VHI) add necessary supplementary information to clinical and physiological assessment. There are a few studies about relation between VHI and disease severity in PD, although none of them showed any significant correlation. The goal of this study was to find correlation between these variables in Iranian PD patients. METHOD: This cross-sectional, analytical and non-interventional study was done on 23 PD patients who reported a voice disorder related to their disease. They were selected from attendants of movement disorders clinic of Hazrat Rasool Akram Hospital. The relationship between disease severity (according to Hoehn and Yahr/H&Y and Unified Parkinson's Disease Rating Scale-part3 /UPDRS-III) and VHI questionnaire (and its 3 domains) was investigated based on patients' sex, UPDRS-III score H&Y and VHI. RESULTS: Total VHI and its 3 domains had no relationship with disease severity (H&Y) in all patients and by sex separation. However, there was a positive correlation between VHI and disease severity (UPDRS-III) (r = 0.485). There was also a relation between physical and functional domains of VHI and UPDRS (rP=0.530, rF=0.479) while no relationship observed regarding sex differences. 9 out of 18 UPDRS-III items had strong relationship with VHI (total and 3subscales). CONCLUSION: Iranian PD patients feel handicap according to voice disorder caused by PD. Patient satisfaction of voice decreases with the disease severity and progression. A larger sample size is necessary to find relationship in genders. VHI is an important issue could be offered to be used in PD beside other assessments.