What could posturography tell us about balance in essential tremor?

BACKGROUND: Essential tremor (ET) is a neurological disorder characterized primarily by action tremor. Balance impairments in ET patients were formerly considered to be uncommon and simply age-related. However quantitative assessment with posturography has revealed impairments in control of both static and dynamic balance. RESEARCH QUESTION: The aim of the present study is to assess postural stability with different posturographic techniques in ET patients. METHODS: A prospective cross-sectional study conducted in two University Hospitals. Eleven patients diagnosed with essential tremor and twelve healthy controls were included. Balance assessment were performed with: sensory organization test (SOT) and limits of stability (LOS) of the computer dynamic posturography (CDP), results of free-field body sway analysis with mobile posturography (Vertiguard®), modified timed up and go test (TUG), Dizziness handicap inventory (DHI) and activities-specific balance confidence scale (ABC). RESULTS: Patients with ET showed poorer scores in the SOT than controls for composite balance and somatosensory input. They also performed worse in LOS tests and Vertiguard® device indicated a higher risk of falling. There were no differences in the modified TUG. The mean score of DHI was 15.64 and 85.16 for ABC. SIGNIFICANCE: Posturography assessment (CDP and Vertiguard®) is more accurate in showing balance impairment in ET patients than clinical evaluation (modified TUG). Balance impairment involves deteriorated processing of somatosensory input which could be explained by cerebellar dysfunction. Balance deficits could be included into future diagnostic criteria.

Alcohol consumption in Menière's disease patients.

Objectives: Dietary changes are useful in the management of Menière's disease; regarding alcohol, many clinicians recommend to avoid or reduce its consumption. However, there are no researches aimed to evaluate whether habitual alcohol consumption is more prevalent and/or more intense in patients with Menière's disease.Methods: Cross-sectional, observational, case-control study, including three groups: patients with Menière's disease, patients with vertigo of other origins, and control subjects. Alcohol consumption was compared between these three groups. Participants in this study were grouped according to alcohol consumption as follows: categorization A1 (nonalcohol vs. alcohol consumers), categorization A2 (nonalcohol, low, moderate, and high alcohol consumers), and categorization A3 (light alcohol consumers: nonconsumers plus low consumers; heavy alcohol consumers: moderate plus high consumers).Results: A total of 180 subjects were included in this study (72 in group A, 72 in group B, and 36 in control group); 117 were women. The mean age was 52.7 years. Mean alcohol consumption was 41.22 g/week. Average consumption of alcohol in group A (50.42 g/week) was higher than in other two groups (36.53 g/week in B and 32.22 g/week in C), but differences were not statistically significant. In Menière's group, light alcohol consumers showed age at onset of symptoms (49.39 years) lower than heavy alcohol consumers (55.51 years). No relationship was observed between alcohol consumption and uni or bilateral affectation.Discussion: It is possible that alcohol consumption delays the age at onset of Menière's disease. A hypothetical explanation is the inhibitory effect of alcohol on hypothalamic production of vasopressin. A reduced release of this neurohormone would increase diuresis and decrease endolymphatic pressure.

Normative data for static balance testing in healthy individuals using open source computerized posturography.

PURPOSE: Computerized posturography is the gold standard for balance assessment. Because of the great cost and dimensions of commercial equipments, low-cost and portable devices have been developed and validated, such as RombergLab, a software in open source term which works connected with a low-cost force platform. The objective of this study was to obtain normative posturography data using this software. METHODS: A multicentric prospective and descriptive study, with 350 healthy participants, was designed. Static postural stability (measured using the modified clinical test of sensory interaction on balance) was evaluated using the software connected to the force platform. Using the confidence ellipse area (CEA) in each condition, global equilibrium score (GES) was calculated and adjusted for significant variable factors using cluster analysis. RESULTS: Mean (SD) GES was 0.72 (0.22). Age (p < 0.01), height (p < 0.01) and recruitment center (p < 0.05) were found as influence factors for GES. Cluster analysis obtained 16 groups stratified by age and height. GES decreases with age and height (p < 0.005). No significant interaction of age nor height was found with GES in these clusters (p > 0.05). After correction for height and age, GES was no longer influenced by the recruitment center (p > 0.05). CONCLUSIONS: With the introduction of the global equilibrium score values of the present study into the software, we consider RombergLab v1.3 a reference posturography tool for healthy individuals. Further studies are needed for validating it as a suitable instrumented test for screening between healthy and pathologic subjects and its reliability over time for the follow-up of patients.

Caffeine intake and Menière's disease: Is there relationship?

OBJECTIVES: Although it is commonly recognized that dietary restrictions may improve the clinical course of Menière's disease, their effectiveness has not been definitely demonstrated. The aim of this study was to examine whether caffeine consumption could be involved in Menière's disease. METHODS: Cross-sectional, observational, case-control study, comparing caffeine consumption (intake of coffee, tea, kola-type beverages, energy drinks, and chocolate-containing beverages or foods) between patients with Menière's disease (group A) and patients affected by vertigo with other origins (group B) and/or control subjects (group C). PATIENTS: 180 subjects (72 in group A, 72 in group B, and 36 in group C). Caffeine intake was categorized in four levels: very low (0-25 mg/day), low (26-100 mg/day), moderate (101-300 mg/day), and high (≥301 mg/day). Very low and low intake were considered light consumption, and moderate and high intake, heavy consumption. RESULTS: Mean daily caffeine intake was 175.8 mg. Menière's disease patients showed a daily caffeine intake (222 mg) greater than those not affected by this disease (145 mg). Excluding in group B migraine patients, differences in caffeine intake are significant among the three groups (P = 0.021). There were significantly more heavy-consumers in group A than in other two groups jointed (P = 0.024; OR = 1.301, IC95% (1.015;1.668)). In group A, the age at onset of symptoms in caffeine consumers (49.7 years) was lower than in non-consumers (55.9 years). DISCUSSION: It should be recommended to reduce caffeine intake in those population groups with higher risk of Menière's disease (e.g. subjects with family members suffering from this disease).

Is posturography able to identify fallers in patients with Parkinson's disease?

INTRODUCTION: Parkinson' disease (PD) is one of the most prevalent neurodegenerative diseases, and more than half of patients with PD experience falls. Research for clinically useful risk factors predicting falls has yielded inconsistent findings so far. Hence the aim of the study is to validate two different posturography techniques and one modified-timed up and go test (TUG) in discriminating fallers and non-fallers among PD patients. METHODS: 32 patients diagnosed with idiopathic PD were assessed with: Dizziness handicap inventory, Activities-specific balance confidence scale, modified-TUG, sensorial organization test (SOT) and limits of stability (LOS) of computer dynamic posturography, results of free-field body sway analysis with Vertiguard device and number of falls. RESULTS: Fallers had longer time to perform modified-TUG and required more steps. On average, fallers performed SOT and LOS significantly worse and Vertiguard device indicated a higher risk of falling. Based on the area under the curve of receiver operating characteristics analyses, the overall accuracy of directional control of LOS and steps in modified-TUG are close to 0.9 (high accuracy). Also assessment with Vertiguard device is more efficient in identifying fallers than the parameters of SOT. DISCUSSION: Our results indicate that LOS, mobile posturography (Vertiguard), vestibular input of SOT and number of steps taken in modified-TUG are very useful to identify fallers in PD patients.