Systematic review of studies on exposure to arsenic in drinking water and cognitive and neurobehavioral effects.

An association between exposure to arsenic (As) and neurologic and behavioral effects has been reported in some studies, but no systematic review is available of the evidence linking As in drinking water and neurobehavioral effects after consideration of study quality and potential confounding, with focus on low-level circumstances of exposure. We conducted a systematic review and reported it in compliance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, through a search of the databases PubMed, Web of Science, Scopus, and Embase. We included in the review the studies reporting results based on exposure from drinking water in humans. Endpoints were heterogeneous across studies, so we classified them into eight broad domains and developed an ad-hoc system to evaluate their methodological quality, based on three tiers. It was not possible to conduct meta-analysis because of the heterogeneity in exposure assessment and in the definition and assessment of outcomes. The search identified 18,518 articles. After elimination of duplicates and irrelevant articles, we retained 106 articles which reported results on As exposure and neurobehavioral effects, of which 22 reported risk estimates from exposure in drinking water (six among adults and 16 among children). None of the studies was conducted blindly. Among the studies in adults, two, which were conducted in highly exposed populations, were classified as high quality. These two studies were broadly consistent in reporting an association between exposure to As and decline in cognitive function; however, they provide no evidence of an association for exposure below 75 µg/L. The four lower-quality studies were based on populations with low exposure; these studies reported associations with inconsistent outcomes, few of which remained statistically significant after adjustment for multiple comparisons. Among the five high-quality studies of children, one reported an association between As in drinking water and intellectual function, whereas none of the other studies reported an association with different neurobehavioral indicators, after adjusting for potential confounders and multiple comparisons. Out of seven intermediate-quality studies, three reported an association with cognitive function or other outcomes; but sources of bias were not adequately controlled. The remaining studies were negative. The four low-quality studies did not contribute to the overall evidence because of methodological limitations. Our assessment of the available literature showed a lack of evidence for a causal association between exposure to As in drinking water and neurobehavioral effects. To clarify whether such an association exists, further studies prospectively evaluating changes in both the concentration of As in drinking water during the life course, and neurobehavioral outcomes, as well as appropriately controlling for potential confounders, are needed.

Levodopa-induced orthostatic hypotension in parkinsonism: A red flag of autonomic failure.

BACKGROUND AND PURPOSE: Levodopa (LD) is the main treatment for parkinsonism, but its use may be limited by a potential hypotensive effect. METHODS: We evaluated the cardiovascular effect of LD performing head-up tilt test (HUTT) before and 60 min after 100/25 mg LD/dopa-decarboxylase inhibitor (pre-LD vs. post-LD HUTT) in 164 patients with parkinsonism on chronic LD treatment. Features predictive of LD-induced orthostatic hypotension (OH) were assessed by logistic regression analysis. RESULTS: Basal supine blood pressure (BP) and heart rate (HR) decreased after LD. During post-LD HUTT, BP drop and HR increase were significantly greater than at pre-LD HUTT. Thirty-eight percent of patients had OH at post-LD HUTT compared to 22% of patients presenting OH at pre-LD HUTT (p < 0.001). Risk factors for LD-induced/worsened OH were pre-LD OH (odds ratio [OR] = 36, 95% confidence interval [CI] = 10-131), absence of overshoot at Valsalva maneuver (OR = 9, 95% CI = 4-20), and pathological Valsalva ratio (OR = 6, 95% CI = 2-15). CONCLUSIONS: LD administration caused/worsened hypotension in both supine and orthostatic conditions. Patients with cardiovascular autonomic failure had a higher risk of developing LD-induced OH. In clinical practice, LD-induced OH could represent a red flag for cardiovascular autonomic failure.

Pervasive and diffuse muscle activity during REM sleep and non-REM sleep characterises multiple system atrophy in comparison with Parkinson's disease.

Multiple system atrophy (MSA) and Parkinson's disease (PD) may share overlapping features particularly at early disease stage, including sleep alterations, but have profoundly different prognoses. Certain sleep phenomena and disorders of motor control are more prevalent in multiple system atrophy, such as REM sleep behaviour disorder (RBD). We quantitatively tested whether pervasive muscle activity during sleep occurs in subjects with multiple system atrophy versus Parkinson's disease. Laboratory polysomnographic studies were performed in 50 consecutive subjects with Parkinson's disease and 26 age- and gender-matched subjects with multiple system atrophy at <5 years from disease onset. The distributions of normalised electromyographic activity of submentalis, wrist extensor, and tibialis anterior muscles in different wake-sleep states during the night were analysed. Subjects with multiple system atrophy had significantly higher activity of submentalis, wrist extensor, and tibialis anterior muscles than subjects with Parkinson's disease during non-REM sleep, including separately in stages N1, N2, and N3, and during REM sleep, but not during nocturnal wakefulness. The activity of wrist extensor and tibialis anterior muscles during non-REM sleep and the activity of tibialis anterior muscles during REM sleep were also significantly higher in subjects with multiple system atrophy and RBD than in subjects with Parkinson's disease and RBD. In conclusion, with respect to Parkinson's disease, multiple system atrophy is characterised by a pervasive and diffuse muscle overactivity that involves axial and limb muscles and occurs not only during REM sleep, but also during non-REM sleep and between subjects with comorbid RBD.

How resistant are levodopa-resistant axial symptoms? Response of freezing, posture, and voice to increasing levodopa intestinal infusion rates in Parkinson disease.

BACKGROUND AND PURPOSE: Treatment of freezing of gait (FoG) and other Parkinson disease (PD) axial symptoms is challenging. Systematic assessments of axial symptoms at progressively increasing levodopa doses are lacking. We sought to analyze the resistance to high levodopa doses of FoG, posture, speech, and altered gait features presenting in daily-ON therapeutic condition. METHODS: We performed a pre-/postinterventional study including patients treated with levodopa/carbidopa intestinal gel infusion (LCIG) with disabling FoG in daily-ON condition. Patients were evaluated at their usual LCIG infusion rate (T1), and 1 h after 1.5× (T2) and 2× (T3) increase of the LCIG infusion rate by quantitative outcome measures. The number of FoG episodes (primary outcome), posture, speech, and gait features were objectively quantified during a standardized test by a blinded rater. Changes in motor symptoms, dyskinesia, and plasma levodopa concentrations were also analyzed. RESULTS: We evaluated 16 patients with a mean age of 69 ± 9.4 years and treated with LCIG for a mean of 2.2 ± 2.1 years. FoG improved in 83.3% of patients by increasing the levodopa doses. The number of FoG episodes significantly decreased (mean = 2.3 at T1, 1.7 at T2, 1.2 at T3; p = 0.013). Posture and speech features did not show significant changes, whereas stride length (p = 0.049), turn duration (p = 0.001), and turn velocity (p = 0.024) significantly improved on doubling the levodopa infusion rate. CONCLUSIONS: In a short-term evaluation, the increase of LCIG dose can improve "dopa-resistant" FoG and gait issues in most advanced PD patients with overall good control of motor symptoms in the absence of clinically significant dyskinesia.

Screening for impulse control disorders in Parkinson's disease and dopamine agonist use: a study of pharmacokinetic and psychological risk factors.

INTRODUCTION: Dopamine agonist (DA) use is considered the main risk factor for impulse control disorder (ICD) development in Parkinson's disease (PD). Besides DAs, personality traits and cognitive features may represent risk factors for ICDs. The primary aim of this study was to investigate differences in DA plasma concentrations in PD patients with and without a positive screening for ICDs according to validated tools. The secondary aim was to compare the psychological profile between ICD positive and negative screened patients. METHODS: PD patients receiving chronic DA therapy were screened for ICDs according to the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease (QUIP). Blood samples for measurement of DA (pramipexole, ropinirole, rotigotine) trough plasma concentrations were drawn in the morning, at mean 16-19 h from the last DA dose. Patients' psychological profile was investigated by Millon Clinical Multiaxal Inventory III and Barratt Impulsiveness Scale (BIS-11). RESULTS: One hundred and five PD patients were enrolled. Forty-one patients (39%) were QUIP positive, mainly for binge eating and hobbyism. Median plasma concentrations of pramipexole (n = 71, 66%), ropinirole (n = 21, 19%), and rotigotine (n = 16, 15%) were similar between QUIP positive and negative patients. QUIP positive patients showed higher motor impulsiveness (p = 0.04) and tended to higher total impulsiveness (p = 0.05). CONCLUSION: This is the first prospective study to evaluate the relationship between DA plasma concentrations and ICDs risk in PD patients. DA plasma levels were overlapping between QUIP positive and negative patients. BIS-11, particularly the motor impulsiveness subscale, might be a useful screening tool in PD patients eligible for DA therapy.

Digenic inheritance of STUB1 variants and TBP polyglutamine expansions explains the incomplete penetrance of SCA17 and SCA48.

PURPOSE: This study aimed to unravel the genetic factors underlying missing heritability in spinocerebellar ataxia type 17 (SCA17) caused by polyglutamine-encoding CAG/CAA repeat expansions in the TBP gene. Alleles with >49 CAG/CAA repeats are fully penetrant. Most patients, however, carry intermediate TBP41-49 alleles that show incomplete penetrance. METHODS: Using next-generation sequencing approaches, we investigated 40 SCA17/TBP41-54 index patients, their affected (n = 55) and unaffected (n = 51) relatives, and a cohort of patients with ataxia (n = 292). RESULTS: All except 1 (30/31) of the index cases with TBP41-46 alleles carried a heterozygous pathogenic variant in the STUB1 gene associated with spinocerebellar ataxias SCAR16 (autosomal recessive) and SCA48 (autosomal dominant). No STUB1 variant was found in patients carrying TBP47-54 alleles. TBP41-46 expansions and STUB1 variants cosegregate in all affected family members, whereas the presence of either TBP41-46 expansions or STUB1 variants individually was never associated with the disease. CONCLUSION: Our data reveal an unexpected genetic interaction between STUB1 and TBP in the pathogenesis of SCA17 and raise questions on the existence of SCA48 as a monogenic disease with crucial implications for diagnosis and counseling. They provide a convincing explanation for the incomplete penetrance of intermediate TBP alleles and demonstrate a dual inheritance pattern for SCA17, which is a monogenic dominant disorder for TBP≥47 alleles and a digenic TBP/STUB1 disease (SCA17-DI) for intermediate expansions.

The Bologna motor and non-motor prospective study on parkinsonism at onset (BoProPark): study design and population.

OBJECTIVE: The Bologna motor and non-motor prospective study on parkinsonism at onset (BoProPark) was designed to prospectively characterize motor and non-motor features in patients with a progressive neurodegenerative disease starting with parkinsonism since early disease stage and to investigate their diagnostic and prognostic role in the differential diagnosis of Parkinson's disease from atypical parkinsonisms. The aim of this paper is to describe the method and population of the BoProPark study. METHODS: Patients referred to our Department with parkinsonism within 3 years from motor onset were recruited. Secondary causes of parkinsonism were excluded. Each patient underwent a comprehensive evaluation of motor and non-motor symptoms, assessed by means of quantitative, objective instrumental tests in addition to scales and questionnaires. The evaluations were performed at enrolment (T0), after 16 months (T1) and after 5 years (T2). Diagnoses were made according to consensus criteria. RESULTS: We recruited 150 patients, with mean age 61.5 ± 9.8 years and mean disease duration 20 ± 9 months. H&Y stage was 1 in 47.3% and 2 in 46.7% of cases. Mean UPDRS-III was 17.7 ± 9.2. Fifty-four patients were on dopaminergic treatment with median levodopa equivalent daily dose (LEDD) of 200 mg. CONCLUSIONS: We expect that the prospective nature of the BoProPark study as well as the comprehensive, instrumental evaluation of motor and non-motor symptoms in patients with parkinsonism will provide important new insights for both clinical practice and research. Our data could be used for comparison with other cohorts and shared with national and international collaborators to develop new innovative projects.

Observing movement disorders: best practice proposal in the use of video recording in clinical practice.

Clinical evaluation is of utmost importance in the semeiological description of motor disorders which often require video recording to highlight subtle signs and their subsequent evolution. After reviewing 1858 video recordings, we composed a suitable list of video-documentation maneuvers, classified semeiologically in the form of a "video recording protocol", to guarantee appropriate documentation when filming movement disorders. Aware that our proposed filming protocol is far from being exhaustive, by suggesting a more detailed documenting approach, it could help not only to achieve a better definition of some disorders, but also to guide neurologists towards the correct subsequent examinations. Moreover, it could be an important tool for the longitudinal evaluation of patients and their response to therapy. Finally, video recording is a powerful teaching tool as visual teaching highly improves educational training.

Interobserver reliability of ICSD-3 diagnostic criteria for disorders of arousal in adults.

PURPOSE: Disorders of arousal include confusional arousals, sleepwalking and sleep terrors. The diagnosis of disorders of arousal is based on the clinical criteria established in the International Classification of Sleep Disorders, third edition, although the interobserver reliability of these criteria has never been investigated. The aim of this study was to estimate the inter-rater reliability of the diagnostic criteria for disorders of arousal throughout the whole life in order to understand their feasibility in clinical daily activity and in multicenter observational studies. METHODS: Three raters interviewed 126 subjects (patients complaining of sleep disorders, headache, and healthy subjects), aged 18-80 years, with a standardized questionnaire created by applying the International Diagnostic Criteria for Disorders of Arousal. RESULTS: An "almost perfect" inter-rater reliability for disorders of arousal criteria and the final diagnosis was found among the raters (kappa 0.89 for confusional arousals, 0.87 for sleepwalking, and 0.87 for sleep terrors). CONCLUSIONS: The International Classification of Sleep Disorders, Third Edition criteria are adequate for a reliable diagnosis of disorders of arousal. Further validation studies, confirming DOA diagnosis with video polysomnography, are needed to investigate the predictive value of ICSD-3 criteria.

REM sleep behavior disorder, autonomic dysfunction and synuclein-related neurodegeneration: where do we stand?

INTRODUCTION: From newfound parasomnia to a marker of future synucleinopathy, since its first description in 1986, REM sleep behavior disorder (RBD) has been systematically tackled from virtually many viewpoints in basic, translational, and clinical studies. The time delay between RBD and synucleinopathy onset offers an exceptional window for observation and design of neuroprotective trials. In the last few years, research has focused on characterizing possible differences within RBD patients in order to draw potential profiles more or less susceptible to further neurodegeneration. Attention has been drawn towards autonomic dysfunction in RBD as one of such variables. OVERVIEW: In this review, REM sleep physiology and relevant brain anatomy is briefly mentioned and integrated with neuroanatomical and physiological concepts regarding the central autonomic network. A detailed summary of works showing the presence of autonomic dysfunction in RBD is provided, and clinical and electrophysiological features of RBD in synucleinopathies are discussed. A short overview of RBD in other neurodegenerative diseases is also provided.

Human figure drawing distinguishes Alzheimer's patients: a cognitive screening test study.

To study human figure drawing in a group of Alzheimer's disease (AD) patients and compare it with a group of patients with mild cognitive impairment (MCI) and controls. We evaluated consecutive outpatients over a one-year period. Patients were classified as affected by AD or by MCI. All patients and controls underwent a simplified version of the human-figure drawing test and MMSE. A qualitative and quantitative analysis of all human figures was obtained. 112 AD, 100 MCI patients and 104 controls were enrolled. AD patients drew human figures poor in details and globally smaller than MCI patients and controls. Human figures drawn by MCI patients are intermediate in body height between those of the AD patients and the healthy subjects. The head-to-body ratio of human figures drawn by AD patients is greater than controls and MCI patients, while the human figure size-relative-to-page space index is significantly smaller. Body height is an independent predictor of cognitive impairment correlating with its severity and with the number of the figure's details. Human figures drawn by AD patients are different from those drawn by healthy subjects and MCI patients. Human figure drawing test is a useful tool for orienting cognitive impairment's diagnosis.

Effect of Alzheimer's disease risk and protective factors on cognitive trajectories in subjective memory complainers: An INSIGHT-preAD study.

INTRODUCTION: Cognitive change in people at risk of Alzheimer's disease (AD) such as subjective memory complainers is highly variable across individuals. METHODS: We used latent class growth modeling to identify distinct classes of nonlinear trajectories of cognitive change over 2 years follow-up from 265 subjective memory complainers individuals (age 70 years and older) of the INSIGHT-preAD cohort. We determined the effect of cortical amyloid load, hippocampus and basal forebrain volumes, and education on the cognitive trajectory classes. RESULTS: Latent class growth modeling identified distinct nonlinear cognitive trajectories. Education was associated with higher performing trajectories, whereas global amyloid load and basal forebrain atrophy were associated with lower performing trajectories. DISCUSSION: Distinct classes of cognitive trajectories were associated with risk and protective factors of AD. These associations support the notion that the identified cognitive trajectories reflect different risk for AD that may be useful for selecting high-risk individuals for intervention trials.

Melanopsin retinal ganglion cell loss in Alzheimer disease.

OBJECTIVE: Melanopsin retinal ganglion cells (mRGCs) are photoreceptors driving circadian photoentrainment, and circadian dysfunction characterizes Alzheimer disease (AD). We investigated mRGCs in AD, hypothesizing that they contribute to circadian dysfunction. METHODS: We assessed retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) in 21 mild-moderate AD patients, and in a subgroup of 16 we evaluated rest-activity circadian rhythm by actigraphy. We studied postmortem mRGCs by immunohistochemistry in retinas, and axons in optic nerve cross-sections of 14 neuropathologically confirmed AD patients. We coimmunostained for retinal amyloid ß (Aß) deposition and melanopsin to locate mRGCs. All AD cohorts were compared with age-matched controls. RESULTS: We demonstrated an age-related optic neuropathy in AD by OCT, with a significant reduction of RNFL thickness (p = 0.038), more evident in the superior quadrant (p = 0.006). Axonal loss was confirmed in postmortem AD optic nerves. Abnormal circadian function characterized only a subgroup of AD patients. Sleep efficiency was significantly reduced in AD patients (p = 0.001). We also found a significant loss of mRGCs in postmortem AD retinal specimens (p = 0.003) across all ages and abnormal mRGC dendritic morphology and size (p = 0.003). In flat-mounted AD retinas, Aß accumulation was remarkably evident inside and around mRGCs. INTERPRETATION: We show variable degrees of rest-activity circadian dysfunction in AD patients. We also demonstrate age-related loss of optic nerve axons and specifically mRGC loss and pathology in postmortem AD retinal specimens, associated with Aß deposition. These results all support the concept that mRGC degeneration is a contributor to circadian rhythm dysfunction in AD.

Precuneal Thickness and Depression in Parkinson Disease.

BACKGROUND: Depression-related gray matter changes in Parkinson disease (PD) patients have been reported, although studies investigating cortical thickness in early-stage disease are lacking. OBJECTIVE: We aimed to evaluate cortical changes related to depression in early-stage PD patients with an extensive neuropsychological evaluation. METHODS: 17 PD patients and 22 healthy controls underwent a 1.5-T brain MR protocol, and voxel-wise differences in cortical thickness among patients with (n = 6) and without (n = 11) depression and controls were evaluated using FreeSurfer software. RESULTS: Cortical thickness was increased in the precuneus bilaterally in PD patients with depression compared to the other groups (number of vertices >100; p < 0.001, uncorrected) with a direct correlation with the Beck Depression Inventory score (p < 0.001, uncorrected). CONCLUSION: Precuneal cortical thickening is evident in PD patients with mild-moderate depression even in the early stages of the disease. This finding may reflect the early involvement of this region in the development of PD-related depression.

Postoperative outcome of body core temperature rhythm and sleep-wake cycle in third ventricle craniopharyngiomas.

OBJECTIVE One of the more serious risks in the treatment of third ventricle craniopharyngiomas is represented by hypothalamic damage. Recently, many papers have reported the expansion of the indications for the endoscopic endonasal approach (EEA) to be used for these tumors as well. The aim of this study was to assess the outcome of sleep-wake cycle and body core temperature (BCT), both depending on hypothalamic control, in patients affected by craniopharyngiomas involving the third ventricle that were surgically treated via an EEA. METHODS All consecutive adult patients with craniopharyngiomas that were treated at one center via an EEA between 2014 and 2016 were prospectively included. Each patient underwent neuroradiological, endocrinological, and ophthalmological evaluation; 24-hour monitoring of the BCT rhythm; and the sleep-wake cycle before surgery and at follow-up of at least 6 months. RESULTS Ten patients were included in the study (male/female ratio 4:6, mean age 48.6 years, SD 15.9 years). Gross-total resection was achieved in 8 cases. Preoperative BCT rhythm was pathological in 6 patients. After surgery, these disturbances resolved in 2 cases, improved in another 3, and remained the same in 1 patient; also, 1 case of de novo onset was observed. Before surgery the sleep-wake cycle was pathological in 8 cases, and it was restored in 4 patients at follow-up. After surgery the number of patients reporting diurnal naps increased from 7 to 9. CONCLUSIONS The outcome of the sleep-wake cycle and BCT analyzed after EEA in this study is promising. Despite the short duration of the authors' experience, they consider these results encouraging; additional series are needed to confirm the preliminary findings.

Diagnosis and management of autonomic failure in neurodegenerative disorders.

BACKGROUND: One of the hallmarks of the α-synucleinopathies is the degeneration of the autonomic nervous system. SUMMARY: This review discusses the diagnosis and management of cardiovascular autonomic failure within the context of the α-synucleinopathies. In addition, it outlines the utility of various laboratory assessments including cardiovascular reflex tests for the differential diagnoses of these disorders, as well as general disease management strategies. Key Messages: Laboratory investigations assessing the autonomic control of the cardiovascular system are useful in the differential diagnosis of α-synucleinopathies, especially in early stages of disease. CLINICAL IMPLICATIONS: The characterization of the different features of AF in patients with α-synucleinopathies is challenging because it might help to improve the accuracy of the differential diagnosis between these diseases at onset. Further cardiovascular AF has been demonstrated to have a negative prognostic role in α-synucleinopathies, therefore an early detection of cardiovascular dysautonomia allows to positively impact the disease course guiding the appropriate therapy.

Orthostatic hypotension and cognitive impairment: a dangerous association?

Many studies have addressed the relation between orthostatic hypotension (OH) and cognitive impairment (CI) in the elderly, in mild cognitive impairment, vascular and neurodegenerative dementias and movement disorders, such as Parkinson's disease. However, results concerning both the increased coexistence of the two conditions and their causal relationship remain controversial. According to the literature three hypotheses can be formulated on the relation between OH and CI. In neurodegenerative disease, OH and CI may result from a common pathological process which affects areas involved in both cognition and cardiovascular autonomic control. Alternatively, OH may lead to cerebral hypoperfusion which is supposed to play a role in the development of CI. Finally, recent data suggest that CI should probably be considered more a transient symptom of OH than a chronic effect. This study reviews the literature reports on the relationship between OH and CI, and emphasises the need for longitudinal studies designed to investigate this topic.

Cognitive and sleep features of multiple system atrophy: review and prospective study.

BACKGROUND: The profile and degree of cognitive impairment in Multiple System Atrophy (MSA) and the impact of sleep disorders, REM sleep behavior disorder (RBD) in particular, in parkinsonism-related cognitive deficits are currently being debated. SUMMARY: We reviewed the cognitive, affective and sleep findings in MSA and also carried out a longitudinal investigation of 10 MSA patients. At the first evaluation, 3 patients showed isolated cognitive deficits. After a mean of 16 months, these patients remained unchanged, while 1 patient worsened from a normal condition. No significant differences emerged when the cognitive, affective and video-polysomnographic findings of MSA-P and MSA-C were compared. Depression was present in half of the patients, although it did not influence their cognitive performance. Comparisons between the first and second evaluation data showed significant worsening in visual attention and in ADL/IADL and UMSARS. KEY MESSAGES: Isolated cognitive deficits are evidenced in a minority of MSA patients with the absence of a clear-cut diagnosis of dementia in the early stages of the disease. Attention and executive functions are often impaired. This study with a short follow-up period showed that RBD, although present in almost all patients affected by MSA, does not appear a clear early marker of cognitive impairment. Future longer-term studies with a larger patient sample are thus encouraged.

Simple verbal analogies test: normative data on a short task exploring abstract thinking.

BACKGROUND AND AIMS: The simple verbal analogies test (SVAT) is a short neuropsychological task requiring few minutes of administration that explores inductive verbal abstract thinking. It already showed a good specificity and sensitivity in discriminating normal controls from probable Alzheimer's disease patients. Verbal working memory, semantic knowledge and memory and word-finding ability are also involved in performing analogies. The aim of this study is to provide the normative values of this test in a sample of normal controls and corrections of raw scores and equivalent scores. METHODS AND RESULTS: We determined the normative values of SVAT in a sample of 424 normal controls to provide corrections of raw scores and equivalent scores. CONCLUSIONS: SVAT is a useful test to assess executive functions, working memory and to discriminate between cognitive deterioration and normal aging.

Exploring Cardiovascular Autonomic Function before and after Chronic Deep Brain Stimulation in Parkinson's Disease.

BACKGROUND: Blood pressure control in Parkinson's disease (PD) under subthalamic deep brain stimulation (STN-DBS) is influenced by several intertwined aspects, including autonomic failure and levodopa treatment. OBJECTIVE: To evaluate the effect of chronic STN-DBS, levodopa, and their combination on cardiovascular autonomic functions in PD. METHODS: We performed cardiovascular reflex tests (CRTs) before and 6-months after STN-DBS surgery in 20 PD patients (pre-DBS vs. post-DBS). CRTs were executed without and with medication (med-OFF vs. med-ON). RESULTS: CRT results and occurrence of neurogenic orthostatic hypotension (OH) did not differ between pre- and post-DBS studies in med-OFF condition. After levodopa intake, the BP decrease during HUTT was significantly greater compared to med-OFF, both at pre-DBS and post-DBS evaluation. Levodopa-induced OH was documented in 25% and 5% of patients in pre-DBS/med-ON and post-DBS/med-ON study. CONCLUSION: Chronic stimulation did not influence cardiovascular responses, while levodopa exerts a relevant hypotensive effect. The proportion of patients presenting levodopa-induced OH decreases after STN-DBS surgery.