Habilidades motoras y de procesamiento en personas con enfermedad de Parkinson en comparación con adultos mayores sanos. Un estudio transversal / Motor and process skills of people with parkinson’s disease compared to healthy older adults. A cross-sectional study

Introducción Tanto la enfermedad de Parkinson (EP) como el proceso de envejecimiento están asociados con limitaciones funcionales. El objetivo de este estudio fue determinar las diferencias en habilidades motoras y de procesamiento entre individuos con EP y adultos mayores sanos, así como observar cómo la progresión de la enfermedad afecta al desempeño de las habilidades motoras y de procesamiento en pacientes con EP. Sujetos y métodos Se realizó un estudio transversal. Se empleó la medida de la Assessment of Motor and Process Skills (AMPS) para analizar las diferencias en las habilidades motoras y de procesamiento de tareas cotidianas entre personas con EP y adultos mayores sanos, emparejados en edad y sexo. Se administró la sección III de la Unified Parkinson Disease Rating Scale, la escala de Hoehn y Yahr (HY) y la escala de Schwab & England para determinar la gravedad de la enfermedad. Resultados Se reclutó a 70 participantes (49 pacientes con EP y 21 adultos mayores sanos). Nuestros resultados mostraron que incluso en estadios moderados de la enfermedad, tanto las habilidades motoras como las de procesamiento se encontraron deterioradas en los pacientes con EP en comparación con los adultos mayores sanos (p < 0,001). A medida que avanza la enfermedad, las habilidades motoras y de procesamiento presentan un deterioro significativo en las personas con EP. Conclusiones La EP conduce a un mayor deterioro de las habilidades motoras y de procesamiento en comparación con adultos mayores sanos. A medida que avanzan los estadios de la enfermedad según la escala HY, el rendimiento en las habilidades motoras y de procesamiento se deteriora significativamente entre los estadios moderados y avanzados de la EP. Según la escala AMPS, los pacientes con EP no muestran un deterioro en las habilidades de procesamiento hasta el estadio HY IV, pero muestran deterioro motor en los estadios HY II, III y IV. (AU)

INTRODUCTION Both Parkinson’s disease (PD) and the process of ageing are associated with functional limitations. The aim of this study was to determine the differences in motor and process skills between individuals with PD and healthy older adults, as well as to observe how disease progression affects motor and process skills performance in PD patients. SUBJECTS AND METHODS A cross-sectional study was conducted. The Assessment of Motor and Process Skills (AMPS) measure was employed in order to analyze the differences in the motor and process skills of daily tasks in people with PD and healthy older adults age- and sex-matched. Part III of the Unified Parkinson Disease Rating Scale (UPDRS), the Hoehn and Yahr (HY) scale and the Schwab & England scale was administered to determine the severity of the disease. RESULTS Seventy participants (49 patients with PD and 21 healthy older adults) were recruited for this study. Our results showed that even at moderate stages of the disease, both motor and process skills were found deteriorated in PD patients more than older healthy older adults (p < 0.001). As PD progresses, motor and process skills present significantly deterioration. CONCLUSION. PD leads to a greater deterioration in motor and process skills compared to healthy older adults. As disease stages advance according to the HY scale, performance in motor and process skills deteriorates significantly between moderate and advanced PD stages. According to the AMPS scale, PD patients show no impairment of processing skills up to HY IV, but motor impairment at HY stages II, III and IV.

A circuit-based approach to modulate hypersexuality in Parkinson's disease.

AIM: Impulse-control disorder is a common neuropsychiatric complication in Parkinson's disease (PD) under dopamine replacement therapy. Prior studies tested the balance between enhanced desire towards reward and cognitive control deficits, hypothesized to be biased towards the former in impulse control disorders. We provide evidence for this hypothesis by measuring behavioral and neural patterns behind the influence of sexual desire over response inhibition and tools towards functional restoration using repetitive transcranial stimulation in patients with hypersexuality as predominant impulsive disorder. METHODS: The effect of sexual cues on inhibition was measured with a novel erotic stop-signal task under on and off dopaminergic medication. Task-related functional and anatomical connectivity models were estimated in 16 hypersexual and 17 nonhypersexual patients with PD as well as in 17 healthy controls. Additionally, excitatory neuromodulation using intermittent theta-burst stimulation (sham-controlled) was applied over the pre-supplementary motor area in 20 additional hypersexual patients with PD aiming to improve response inhibition. RESULTS: Compared with their nonhypersexual peers, patients with hypersexuality recruited caudate, pre-supplementary motor area, ventral tegmental area, and anterior cingulate cortex while on medication. Reduced connectivity was found between pre-supplementary motor area and caudate nucleus in hypersexual compared with nonhypersexual patients (while medicated), a result paralleled by compensatory enhanced anatomical connectivity. Furthermore, stimulation over the pre-supplementary motor area improved response inhibition in hypersexual patients with PD when exposed to sexual cues. CONCLUSION: This study, therefore, has identified a specific fronto-striatal and mesolimbic circuitry underlying uncontrolled sexual responses in medicated patients with PD where cortical neuromodulation halts its expression.

Validation of the OPTIMIPARK Questionnaire: A Tool to Optimize Treatment in Parkinson's Disease.

Background: Dopamine replacement therapy reduces most motor and nonmotor features of Parkinson's disease. However, with disease progression, adjustments of dopaminergics and the application of advanced therapies must be considered. Objectives: To validate the OPTIMIPARK questionnaire as a tool to help clinicians make therapeutic decisions on patients treated with levodopa. Methods: We tested a questionnaire including 9 items encompassing motor and nonmotor signs, complications, and disability in a multicenter, observational, cross-sectional study. A neurologist (neurologist 1 [N1]) assessed patients according to regular clinical practice and blinded to the OPTIMIPARK questionnaire score. Therapeutic decisions were classified as "no changes," "adjustment of conventional treatment," and "advanced therapy indicated." External neurologists (neurologist 3 [N3] and neurologist 4 [N4]), who only knew the patient age, years of disease, and current treatment, made their therapeutic decisions based on the OPTIMIPARK score. Concordance between the criterion of the N1 versus the OPTIMIPARK-based N3-N4 consensus was analyzed applying weighted κ. The area under Receiving Operating Characteristic (ROC) curves was calculated for OPTIMIPARK scores. Results: A total of 113 patients with Parkinson's disease were included. The OPTIMIPARK-based decision led to a higher proportion of patients requiring therapeutic modification than N1 assessment (74% vs. 60%; P = 0.002). Concordance between the N1 and N3-N4 decisions was moderate, whereas interobserver agreement among N3 and N4 was high. Area Under the Curve(AUC) values of 0.83 and 0.82 were found for "no changes" and "advanced therapy indicated" decisions by the N1 neurologist. Conclusions: OPTIMIPARK might be more sensitive than regular clinical practice in suggesting the need for a therapeutic change. Furthermore, the low and high scores identify with high accuracy well-adjusted patients and candidates for advanced therapy, respectively.

Motor and nonmotor symptoms in patients treated with 24-hour daily levodopa-carbidopa intestinal gel infusion: Analysis of the COmedication Study assessing Mono- and cOmbination therapy with levodopa-carbidopa inteStinal gel (COSMOS).

INTRODUCTION: Patients with advanced Parkinson's disease (APD) commonly experience motor and nonmotor symptoms (NMS) associated with functional limitations and decreased quality of life. We compared motor and nonmotor outcomes in patients with APD receiving 24- versus 16-h levodopa-carbidopa intestinal gel (LCIG). METHODS: Data from COSMOS, a large, real-world, retrospective and cross-sectional, observational study on LCIG and comedication in APD were obtained from medical records and a single patient visit for patients receiving 24- and 16-h LCIG infusion. Changes from baseline were evaluated for motor symptoms, NMS, and clinical characteristics. Safety was also assessed. RESULTS: Data for 401 patients were included in this subanalysis. At the patient visit there were 35 patients on 24-h LCIG and 366 on 16-h LCIG. "Off" time and dyskinesia (duration and severity) were reduced in both groups. In both LCIG treatment groups, prevalence of most symptoms was reduced. There were significant differences in the change from baseline in severity and frequency of freezing of gait with 24-h LCIG versus 16-h LCIG (p = 0.011 and p = 0.038), severity of urinary symptoms (p = 0.006), and frequency of cognitive impairment (p = 0.014) with 24-h LCIG versus 16-h LCIG. Adverse events were similar for both treatment groups and considered tolerable. CONCLUSIONS: LCIG 24-h infusion may be a useful treatment option, when clinically justified, for select patients with APD. CLINICAL TRIAL NUMBER: NCT03362879.

Non-Motor Symptoms in PLA2G6-Associated Dystonia-Parkinsonism: A Case Report and Literature Review.

PLA2G6-dystonia-parkinsonism (PLAN-DP) is characterized by levodopa responsive parkinsonism and dystonia. While neuropsychiatric symptoms and early cognitive decline are also common in this entity there is little information regarding other non-motor symptoms (NMS). Here, we describe a 26-year-old patient with PLAN-DP whose motor symptoms were preceded by mild cognitive impairment and anxiety, and who developed many other NMS as the disease evolved. Furthermore, we reviewed the NMS described in all the PLAN-DP patients published to date. A total of 50 patients with PLAN-DP were identified, 42 of whom developed NMS and in 23 of these cases, NMS preceded the motor symptoms of the disease. Neuropsychiatric symptoms dominated the premotor phase of this condition and cognitive impairment/dementia was the most prevalent NMS. Other NMS were reported infrequently like sleep disorders, autonomic symptoms, pain and hyposmia, and mostly as the disease evolved. NMS are very frequent in PLAN-DP and they may appear before diagnosis or during the course of the disease. Neuropsychiatric symptoms and cognitive decline are the most frequent NMS. The appearance of neuropsychiatric symptoms like depression, anxiety or personality changes prior to a diagnosis of parkinsonism in younger individuals might suggest the presence of PLA2G6 gene mutations.

Effects of contemporary dance and physiotherapy intervention on balance and postural control in Parkinson's disease.

PURPOSE: To describe the effects of a contemporary dance program, combined with conventional physiotherapy, on postural control, satisfaction and adherence in mild-moderate Parkinson's disease (PD) patients. METHODS: A withdrawal/reversion test with three intervention periods. Each period lasts for two months: physiotherapy, physiotherapy + dance and withdrawing dance and continuing with the physiotherapy sessions. Berg Balance Scale (BBS), Timed Up & Go test (TUG), Sensory Organization Test (SOT), Motor Control Test (MCT) and Rhythmic Weigh Shift (RWS) were assessed at T1 (baseline), T2 (post-physiotherapy treatment), T3 (post-physiotherapy and dance) and T4 (post-physiotherapy). A satisfaction questionnaire and adherence were registered. RESULTS: 27 patients (67.32 ± 6.14 yrs) completed the study. Statistical analysis revealed differences between T2-T3 (p = 0.027), T2-T4 (p = 0.029), T1-T3 (p = 0.010) and T1-T4 (p = 0.008) for BBS; and between T1-T2 (p = 0.037), T1-T3 (p = 0.005), T1-T4 (p = 0.004), T2-T3 (p = 0.022) and T2-T4 (p = 0.041) for TUG. Significant differences for CES (p < 0.001), VEST (p = 0.024) and strategy (p = 0.011) were observed, but not for MCT. Lateromedial velocity (p = 0.003) and anteroposterior velocity (p < 0.001) were significant for RWT. Patients showed a high level of satisfaction and adherence. CONCLUSIONS: A short 8-weeks contemporary dance program plus combined physiotherapy shows benefits in functional mobility and balance, with a high degree of satisfaction and adherence in PD.IMPLICATIONS FOR REHABILITATIONContemporary dance, combined with physiotherapy, is a useful therapeutic tool to treat balance disorders and postural control in people with PD.A short 8-weeks contemporary dance program plus combined physiotherapy shows high satisfaction in people with PD.Contemporary dance, combined with physiotherapy, shows high adherence in people with mild-moderate PD to treat postural control.

Concomitant Medication Usage with Levodopa-Carbidopa Intestinal Gel: Results from the COSMOS Study.

BACKGROUND: Levodopa-carbidopa intestinal gel (LCIG) is administered directly to the small intestine of patients with advanced Parkinson's disease (APD) to help maintain stable plasma levodopa levels. OBJECTIVE: The objective of this study was to investigate the effect of LCIG in reducing polypharmacy for the treatment of APD. METHODS: The COmedication Study assessing Mono- and cOmbination therapy with levodopa-carbidopa inteStinal gel (COSMOS) is a large, real-world, multinational observational study investigating comedication use with LCIG. All enrolled patients had used LCIG for ≥12 months and data were collected cross-sectionally (study visit) and retrospectively. The primary endpoint was the percentage of patients using LCIG as monotherapy (without add-on PD medications) at initiation and at 3, 6, 9, and 12 months thereafter. RESULTS: Overall, 409 patients were enrolled from 14 countries and were treated with LCIG for a mean of 35.8 ± 23.2 months. A total of 15.2% of patients initiated LCIG as monotherapy and 31.7% were receiving monotherapy at 12 months after initiation. The mean duration of LCIG monotherapy was 39.3 ± 25.6 months. Use of add-on medications decreased over time with all LCIG regimens. From LCIG initiation to the patient visit, mean off time decreased by 3.8, 4.6, and 3.9 hours/day for LCIG monotherapy, LCIG daytime monotherapy, and LCIG polytherapy groups, respectively, while duration of dyskinesia decreased by 1.7, 2.0, and 1.9 hours/day, respectively. Adverse events likely related to study treatment occurred in 112 patients (27.4%) during LCIG treatment. CONCLUSIONS: LCIG is an effective long-term monotherapy option with a positive risk-benefit profile and contributes to reduced polypharmacy for patients with APD. © 2021 The AbbVie Inc. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Motor Onset Topography and Progression in Parkinson's Disease: the Upper Limb Is First.

OBJECTIVE: To define the motor onset and progression of Parkinson's disease (PD) in a prospective cohort of early unmedicated patients. METHODS: We enrolled a consecutive cohort of recently diagnosed (<18 months) PD patients with unilateral manifestations using age and gender-matched controls. The most affected body region was determined using various clinical standard metrics and objective quantitative kinematic measurements. Parkinson's Progression Markers Initiative data were used for external validation of the results. RESULTS: Twenty-five drug-naive patients and 21 controls were studied. Upper limbs were (92%) the most affected body region at onset as ascertained by patients' self-assessment, neurologists' impression, and Movement Disorders Society Unified Parkinson's Disease Rating Scale score. The upper limb (ie, hand) was the site of onset in 80% of patients. Motor features progressed to involve the lower limb but remained limited to the initially affected body side over a 2-year follow-up. Agreement among the different metrics (96%) confirmed focal upper limb predominant motor impairment at onset. The findings were confirmed by quantitative kinematic analyses and from a cohort of 34 similar patients from the Parkinson's Progression Markers Initiative database. CONCLUSIONS: Motor manifestations in PD start distally in one upper limb. The complexity of the motor repertoire and, consequently, the presumed larger dopaminergic striatal demand for maintaining skillful motor function in the upper limb, may contribute to greater vulnerability of dopaminergic striatal terminals. Recognition of this motor pattern could be used to monitor the evolution of nigrostriatal degeneration and the putative impact of therapies. © 2021 International Parkinson and Movement Disorder Society.

Randomized Trial of Focused Ultrasound Subthalamotomy for Parkinson's Disease.

BACKGROUND: The subthalamic nucleus is the preferred neurosurgical target for deep-brain stimulation to treat cardinal motor features of Parkinson's disease. Focused ultrasound is an imaging-guided method for creating therapeutic lesions in deep-brain structures, including the subthalamic nucleus. METHODS: We randomly assigned, in a 2:1 ratio, patients with markedly asymmetric Parkinson's disease who had motor signs not fully controlled by medication or who were ineligible for deep-brain stimulation surgery to undergo focused ultrasound subthalamotomy on the side opposite their main motor signs or a sham procedure. The primary efficacy outcome was the between-group difference in the change from baseline to 4 months in the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor score (i.e., part III) for the more affected body side (range, 0 to 44, with higher scores indicating worse parkinsonism) in the off-medication state. The primary safety outcome (procedure-related complications) was assessed at 4 months. RESULTS: Among 40 enrolled patients, 27 were assigned to focused ultrasound subthalamotomy (active treatment) and 13 to the sham procedure (control). The mean MDS-UPDRS III score for the more affected side decreased from 19.9 at baseline to 9.9 at 4 months in the active-treatment group (least-squares mean difference, 9.8 points; 95% confidence interval [CI], 8.6 to 11.1) and from 18.7 to 17.1 in the control group (least-squares mean difference, 1.7 points; 95% CI, 0.0 to 3.5); the between-group difference was 8.1 points (95% CI, 6.0 to 10.3; P<0.001). Adverse events in the active-treatment group were dyskinesia in the off-medication state in 6 patients and in the on-medication state in 6, which persisted in 3 and 1, respectively, at 4 months; weakness on the treated side in 5 patients, which persisted in 2 at 4 months; speech disturbance in 15 patients, which persisted in 3 at 4 months; facial weakness in 3 patients, which persisted in 1 at 4 months; and gait disturbance in 13 patients, which persisted in 2 at 4 months. In 6 patients in the active-treatment group, some of these deficits were present at 12 months. CONCLUSIONS: Focused ultrasound subthalamotomy in one hemisphere improved motor features of Parkinson's disease in selected patients with asymmetric signs. Adverse events included speech and gait disturbances, weakness on the treated side, and dyskinesia. (Funded by Insightec and others; ClinicalTrials.gov number, NCT03454425.).

Cortical disinhibition in Parkinson's disease.

In Parkinson's disease, striatal dopamine depletion produces profound alterations in the neural activity of the cortico-basal ganglia motor loop, leading to dysfunctional motor output and parkinsonism. A key regulator of motor output is the balance between excitation and inhibition in the primary motor cortex, which can be assessed in humans with transcranial magnetic stimulation techniques. Despite decades of research, the functional state of cortical inhibition in Parkinson's disease remains uncertain. Towards resolving this issue, we applied paired-pulse transcranial magnetic stimulation protocols in 166 patients with Parkinson's disease (57 levodopa-naïve, 50 non-dyskinetic, 59 dyskinetic) and 40 healthy controls (age-matched with the levodopa-naïve group). All patients were studied OFF medication. All analyses were performed with fully automatic procedures to avoid confirmation bias, and we systematically considered and excluded several potential confounding factors such as age, gender, resting motor threshold, EMG background activity and amplitude of the motor evoked potential elicited by the single-pulse test stimuli. Our results show that short-interval intracortical inhibition is decreased in Parkinson's disease compared to controls. This reduction of intracortical inhibition was obtained with relatively low-intensity conditioning stimuli (80% of the resting motor threshold) and was not associated with any significant increase in short-interval intracortical facilitation or intracortical facilitation with the same low-intensity conditioning stimuli, supporting the involvement of cortical inhibitory circuits. Short-interval intracortical inhibition was similarly reduced in levodopa-naïve, non-dyskinetic and dyskinetic patients. Importantly, intracortical inhibition was reduced compared to control subjects also on the less affected side (n = 145), even in de novo drug-naïve patients in whom the less affected side was minimally symptomatic (lateralized Unified Parkinson's Disease Rating Scale part III = 0 or 1, n = 23). These results suggest that cortical disinhibition is a very early, possibly prodromal feature of Parkinson's disease.

Sexual Dysfunction in Early-Onset Parkinson's Disease: A Cross-Sectional, Multicenter Study.

BACKGROUND: Sexual dysfunction (SD) is one of the least studied non-motor symptoms in Parkinson's disease (PD). OBJECTIVES: To assess sexual function in a cohort of patients with early-onset PD (EOPD) and compare it to a group of healthy controls. METHODS: In this cross-sectional multicenter study, SD was assessed with gender-specific multi-dimensional self-reported questionnaires: The Brief Male Sexual Function Inventory (BSFI-M) and the Female Sexual Function Index (FSFI). Scores between patients and controls were compared and associations between SD and demographical and clinical variables were studied. RESULTS: One hundred and five patients (mean age 47.35±7.8, disease duration 6 (3-11) years, UPDRS part III 17 (10-23) and 90 controls were recruited. The BSFI-M total score was lower in EOPD men than in controls, and specific items were also significantly lower, such as drive, erections, ejaculation, and satisfaction. EOPD women had lower scores than controls in totalFSFI, and certain domains such as lubrication and pain. SD was present in 70.2% of patients and 52.5% of controls. Sexual satisfaction in 35.2% of patients and 81.2% of controls. By gender, male and female patients had more SD than controls but only male patients had more dissatisfaction than controls. Gender, higher depression scores and urinary dysfunction were associated with SD in multivariate analysis; and gender, UPDRS and urinary dysfunction with sexual satisfactionConclusion:In this Spanish cohort, SD and sexual dissatisfaction was more prevalent in EOPD patients than in the general population. Gender and urinary disfunction were associated with SD and sexual dissatisfaction.

Trunk Range of Motion Is Related to Axial Rigidity, Functional Mobility and Quality of Life in Parkinson's Disease: An Exploratory Study.

BACKGROUND: People with Parkinson's disease (PD) present deficits of the active range of motion (ROM), prominently in their trunk. However, if these deficits are associated with axial rigidity, the functional mobility or health related quality of life (HRQoL), remains unknown. The aim of this paper is to study the relationship between axial ROM and axial rigidity, the functional mobility and HRQoL in patients with mild to moderate PD. METHODS: An exploratory study was conducted. Non-probabilistic sampling of consecutive cases was used. Active trunk ROM was assessed by a universal goniometer. A Biodex System isokinetic dynamometer was used to measure the rigidity of the trunk. Functional mobility was determined by the Get Up and Go (GUG) test, and HRQoL was assessed with the PDQ-39 and EuroQol-5D questionnaires. RESULTS: Thirty-six mild to moderate patients with PD were evaluated. Significant correlations were observed between trunk extensors rigidity and trunk flexion and extension ROM. Significant correlations were observed between trunk flexion, extension and rotation ROM and GUG. Moreover, significant correlations were observed between trunk ROM for flexion, extension and rotations (both sides) and PDQ-39 total score. However, these correlations were considered poor. CONCLUSIONS: Trunk ROM for flexion and extension movements, measured by a universal goniometer, were correlated with axial extensors rigidity, evaluated by a technological device at 30°/s and 45°/s, and functional mobility. Moreover, trunk ROM for trunk flexion, extension and rotations were correlated with HRQoL in patients with mild to moderate PD.

Transcranial Magnetic Resonance-Guided Focused Ultrasound Thalamotomy in Essential Tremor: A Comprehensive Lesion Characterization.

BACKGROUND: Transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) thalamotomy is a novel and effective treatment for controlling tremor in essential tremor patients. OBJECTIVE: To provide a comprehensive characterization of the radiological, topographical, and volumetric aspects of the tcMRgFUS thalamic lesion, and to quantify how they relate to the clinical outcomes. METHODS: In this study, clinical and radiological data from forty patients with medically-refractory essential tremor treated with unilateral tcMRgFUS thalamotomy were retrospectively analyzed. Treatment efficacy was assessed with Clinical Rating Scale for Tremor (CRST). Lesions were manually segmented on T1, T2, and susceptibility-weighted images, and 3-dimensional topographical analysis was then carried out. Statistical comparisons were performed using nonparametric statistics. RESULTS: The greatest clinical improvement was correlated with a more inferior and posterior lesion, a bigger lesion volume, and percentage of the ventral intermediate nucleus covered by the lesion; whereas, the largest lesions accounted for the occurrence of gait imbalance. Furthermore, the volume of the lesion was significantly predicted by the number of sonications surpassing 52°C. CONCLUSION: Here we provide a comprehensive characterization of the thalamic tcMRgFUS lesion including radiological and topographical analysis. Our results indicate that the location and volume of the lesion were significantly associated with the clinical outcome and that mid-temperatures may be responsible for the lesion size. This could serve ultimately to improve targeting and judgment and to optimize clinical outcome of tcMRgFUS thalamotomy.

Axial rigidity is related to the risk of falls in patients with Parkinson's disease.

BACKGROUND: Rigidity is a cardinal symptom of Parkinson's disease (PD) and is often clinically assessed by passively flexing and extending a patient's limb. Objective measurements had been employed to examine rigidity in PD subjects, including wrist, elbow or knee. OBJECTIVE: This study aimed to investigate the relationship between an objective measurement of trunk rigidity and risk of falls in patients with mild to moderate PD. METHODS: An isokinetic dynamometer Biodex System 3 was employed to assess trunk rigidity in 36 patients with mild to moderate PD at a University Department in a cross-sectional study. Risk of falls was measured by the Get Up & Go test (GU&G). Disease severity (Hoehn and Yahr staging score and the Unified Parkinson's Disease Rating Scale III), disease duration and functional status (Schwab & England activities of daily living scale) were also evaluated. RESULTS: Significant correlations between trunk extensors rigidity at 45°/s and 60°/s and risk of falls were obtained. A correlation between trunk extensors tone at 30°/s and the GU&G test almost reached significant almost reached statistical significance (r = 0.306; p = 0,066). Significant correlations between trunk flexors-extensors tone and clinical status, disease duration and functional status at 30°/s, 45°/s and 60°/s were also obtained. CONCLUSION: The results from this study suggest that the axial rigidity is related to the risk of falls in patients with mild to moderate PD. Further studies are needed with quantitative devices for axial rigidity assessment to determine the relationship between trunk rigidity in PD patients with higher disease severity and risk of falls.