Mood Associated With Health- and Social Care-Related Quality of Life in Patients With Advanced Multiple Sclerosis.

BACKGROUND: Individuals with advanced multiple sclerosis (MS) have complex care requirements and are more likely to use long-term facilities. This study determined the associations between mood and social care-related quality of life (SCRQOL), and health-related quality of life (HRQOL) and examined the association between HRQOL and SCRQOL. METHODS: Baseline data from a cohort study were used. Patients completed questionnaires, including the Hospital Anxiety and Depression Scale (HADS), Adult Social Care Outcomes Toolkit (ASCOT), and EuroQOL 5D-5L (EQ-5D-5L) and EQ-Visual Analogue Scale (EQ-VAS). Linear regression analyses were employed to assess the relationships between mood and both outcomes of QOL while controlling for relevant confounding factors (ßs; 95% CI). The cross-sectional association between SCRQOL and HRQOL was examined using Pearson correlation coefficients (r). RESULTS: A total of 75 patients, with a mean age of 56.1 years and a disease duration of 17.3 years, were enrolled from a long-term care facility in the Netherlands. Results showed that after controlling for confounders, HADS is an independent determinant of ASCOT (ßs = -.368; 95% CI, -.581 to -.154) and EQ-5D-5L (ßs = -.297; 95% CI, -.507 to -.087). Also, there are significant but weak correlations between ASCOT and EQ-5D-5L (r = 0.242; 95% CI, .015-.468), between ASCOT and EQ-VAS (r = 0.230; 95% CI, .003-.457) and between EQ-5D-5L and EQ-VAS (r = 0.227; 95% CI, .000-.454). CONCLUSIONS: Mood, especially the depression component, is an important determinant of both HRQOL and SCRQOL in advanced MS. Focusing on mood in health care and social care may contribute to the improvement of QOL in a broader sense.

Non-Pharmacological Interventions for Depression and Anxiety in Parkinson's Disease.

Non-pharmacological interventions, including cognitive-behavioral therapy (CBT), non-invasive brain stimulation (NIBS), electroconvulsive therapy (ECT), light therapy (LT), and physical rehabilitation/exercise, have shown promise as effective approaches to treat symptoms of depression and anxiety in individuals with Parkinson's disease (PD). In this narrative literature overview, we discuss the state-of-the-art regarding these treatment options and address future perspectives for clinical practice and research. Non-pharmacological interventions hold promise to treat depression and anxiety in PD. There is meta-analytic evidence for the efficacy of CBT, NIBS, ECT, LT, and exercise on improving depressive symptoms. For the treatment of anxiety symptoms, CBT shows large effects but scientific evidence of other non-pharmacological interventions is limited. Importantly, these treatments are safe interventions with no or mild side-effects. More research is needed to tailor treatment to the individuals' needs and combined interventions may provide synergistic effects.We conclude that non-pharmacological interventions should be considered as alternative or augmentative treatments to pharmacological and neurosurgical approaches for the treatment of depression and anxiety in individuals with PD.

Effects and Mechanisms of Exercise on Brain-Derived Neurotrophic Factor (BDNF) Levels and Clinical Outcomes in People with Parkinson's Disease: A Systematic Review and Meta-Analysis.

INTRODUCTION: Exercise therapy may increase brain-derived neurotrophic factor (BDNF) levels and improve clinical outcomes in people living with Parkinson's disease (PD). This systematic review was performed to investigate the effect of exercise therapy on BDNF levels and clinical outcomes in human PD and to discuss mechanisms proposed by authors. METHOD: A search on the literature was performed on PubMed up to December 2023 using the following key words: Parkinson's disease AND exercise, exercise therapy, neurological rehabilitation AND brain-derived neurotrophic factor, brain-derived neurotrophic factor/blood, brain-derived neurotrophic factor/cerebrospinal fluid AND randomized clinical trial, intervention study. Only randomized clinical trials comparing an exercise intervention to treatment as usual, usual care (UC), sham intervention, or no intervention were included. RESULTS: A meta-analysis of BDNF outcomes with pooled data from five trials (N = 216 participants) resulted in a significant standardized mean difference (SMD) of 1.20 [95% CI 0.53 to 1.87; Z = 3.52, p = 0.0004, I2 = 77%], favoring exercise using motorized treadmill, Speedflex machine, rowing machine, and non-specified exercise. Significant improvements were found in Unified Parkinson's Disease Rating Scale (UPDRS), UPDRS-III, 6 Minute Walk Test (6MWT), and Berg Balance Scale (BBS). Methodological quality of trials was categorized as "good" in three trials, "fair" in one trial, and "poor" in one trial. CONCLUSION: Key results of this systematic review are that exercise therapy is effective in raising serum BDNF levels and seems effective in alleviating PD motor symptoms. Exercise therapy confers neuroplastic effects on Parkinson brain, mediated, in part, by BDNF.

Reservoir-derived subsidies provide a potential management opportunity for novel river ecosystems.

Aquatic ecosystems world-wide are being irreversibly altered, suggesting that new and innovative management strategies are necessary to improve ecosystem function and sustainability. In river ecosystems degraded by dams environmental flows and selective withdrawal (SWD) infrastructure have been used to improve habitat for native species. Yet, few studies have quantified nutrient and food web export subsidies from upstream reservoirs, despite their potential to subsidize downstream riverine food webs. We sampled nutrient, phytoplankton, and zooplankton concentrations in outflows from the Shasta-Keswick reservoir complex in Northern California over a 12-month period to understand how SWD operation and internal reservoir conditions interact to influence subsidies to the Sacramento River. We found that nutrients, phytoplankton, and zooplankton were continuously exported from Shasta Reservoir to the Sacramento River and that gate operations at Shasta Dam were important in controlling exports. Further, our results indicate that gate operations and water-export depth strongly correlated with zooplankton community exports, whereas internal reservoir conditions (mixing and residence time) controlled concentrations of exported zooplankton biomass and chlorophyll a. These results demonstrate that reservoirs can be an important source of nutrient and food web subsidies and that selective withdrawal infrastructure may provide a valuable management tool to control ecosystem-level productivity downstream of dams.

(HIIT-The Track) High-Intensity Interval Training for People with Parkinson's Disease: Individual Response Patterns of (Non-)Motor Symptoms and Blood-Based Biomarkers-A Crossover Single-Case Experimental Design.

INTRODUCTION: Physical exercise is receiving increasing interest as an augmentative non-pharmacological intervention in Parkinson's disease (PD). This pilot study primarily aimed to quantify individual response patterns of motor symptoms to alternating exercise modalities, along with non-motor functioning and blood biomarkers of neuroplasticity and neurodegeneration. MATERIALS & METHODS: People with PD performed high-intensity interval training (HIIT) and continuous aerobic exercise (CAE) using a crossover single-case experimental design. A repeated assessment of outcome measures was conducted. The trajectories of outcome measures were visualized in time series plots and interpreted relative to the minimal clinically important difference (MCID) and smallest detectable change (SDC) or as a change in the positive or negative direction using trend lines. RESULTS: Data of three participants were analyzed and engaging in physical exercise seemed beneficial for reducing motor symptoms. Participant 1 demonstrated improvement in motor function, independent of exercise modality; while for participant 2, such a clinically relevant (positive) change in motor function was only observed in response to CAE. Participant 3 showed improved motor function after HIIT, but no comparison could be made with CAE because of drop-out. Heterogeneous responses on secondary outcome measures were found, not only between exercise modalities but also among participants. CONCLUSION: Though this study underpins the positive impact of physical exercise in the management of PD, large variability in individual response patterns to the interventions among participants makes it difficult to identify clear exercise-induced adaptations in functioning and blood biomarkers. Further research is needed to overcome methodological challenges in measuring individual response patterns.

Is Cardiorespiratory Fitness Independently Associated with Fatigue in Patients with Transient Ischemic Attack or Minor Stroke?

Fatigue is a common complaint and a disabling symptom among patients following transient ischemic attack (TIA) or minor stroke. In patients with stroke, decreased cardiorespiratory fitness (CRF) is believed to be related to increased severity of post-stroke fatigue (PSF). However, this association between PSF and CRF in patients with TIA or minor stroke has been less investigated, and currently there is no proven treatment for PSF. We aimed to determine the association between PSF and CRF in patients with TIA or minor stroke and to find out whether this association was distorted by confounders. A cross-sectional association study was conducted among a total of 119 patients with TIA or minor stroke. PSF was measured by the Fatigue Severity Scale (FSS) and CRF was quantified by maximal exercise capacity (V̇O2max). The FSS showed a significant association with V̇O2max (ß = -0.061, SE: 0.022; p = 0.007). This association was confounded by anxiety (ß = -0.044, SE: 0.020; p = 0.028) and depression (ß = -0.030, SE: 0.022; p = 0.177) as measured by the subscales of the Hospital Anxiety and Depression Scale (HADS). After controlling for HADS scores on depression and anxiety, the univariate relationship between V̇O2max and FSS was no longer significant. These results suggest that the association between PSF and CRF in patients with TIA or minor stroke is weak and significantly confounded by the factors of depression and anxiety.

An Overview of Wearable Haptic Technologies and Their Performance in Virtual Object Exploration.

We often interact with our environment through manual handling of objects and exploration of their properties. Object properties (OP), such as texture, stiffness, size, shape, temperature, weight, and orientation provide necessary information to successfully perform interactions. The human haptic perception system plays a key role in this. As virtual reality (VR) has been a growing field of interest with many applications, adding haptic feedback to virtual experiences is another step towards more realistic virtual interactions. However, integrating haptics in a realistic manner, requires complex technological solutions and actual user-testing in virtual environments (VEs) for verification. This review provides a comprehensive overview of recent wearable haptic devices (HDs) categorized by the OP exploration for which they have been verified in a VE. We found 13 studies which specifically addressed user-testing of wearable HDs in healthy subjects. We map and discuss the different technological solutions for different OP exploration which are useful for the design of future haptic object interactions in VR, and provide future recommendations.

Graded peak cycle ergometer test for cognitively impaired patients with Parkinson's disease: a pilot study.

BACKGROUND: Cognitive decline affects up to 50% of patients with Parkinson's disease (PD) in the course of the disease and may be amenable to exercise interventions. To accurately set adequate training intensities, standardized exercise testing is required but such testing takes considerable time and effort. The aim of this pilot study was to investigate the feasibility of a graded peak cycle ergometer exercise test in cognitively impaired patients with Parkinson's Disease (PD), and to define whether age-predicted maximal heart rate (HRmax) matched measured HRmax. METHODS: A convenience sample of seven patients with PD (Hoehn and Yahr: 2-4, and cognitive impairment (Montreal Cognitive Assessment (MoCA) ≤ 26) completed a graded peak cycle ergometer test to voluntary exhaustion. Borg Rating of Perceived Exertion was used to record the individual's perception of exertion. Pre-defined age-predicted HRmax (calculated as 208-(0.7 × age) was compared with the measured HRmax using Bland-Altman plot and a two-one-sided test. RESULTS: All PD patients completed the graded exercise test between 8-12 minutes, showing therefore 100% compliance to the test protocol. No adverse events occurred. Predicted HRmax and measured HRmax did not differ. CONCLUSION: We demonstrate feasibility of graded peak cycle ergometer testing in PD patients with cognitive impairment. The good correspondence of age-predicted HRmax equation with measured HRmax, in this small sample, may in the future provide clinicians with a tool to define training intensities in cognitively impaired PD, without cardiac disease. However, further research is needed to confirm these results.

Biallelic variants in the SLC13A1 sulfate transporter gene cause hyposulfatemia with a mild spondylo-epi-metaphyseal dysplasia.

Sulfate is the fourth most abundant anion in human plasma but is not measured in clinical practice and little is known about the consequences of sulfate deficiency. Nevertheless, sulfation plays an essential role in the modulation of numerous compounds, including proteoglycans and steroids. We report the first patient with a homozygous loss-of-function variant in the SLC13A1 gene, encoding a renal and intestinal sulfate transporter, which is essential for maintaining plasma sulfate levels. The homozygous (Arg12Ter) variant in SLC13A1 was found by exome sequencing performed in a patient with unexplained skeletal dysplasia. The main clinical features were enlargement of joints and spondylo-epi-metaphyseal radiological abnormalities in early childhood, which improved with age. In addition, autistic features were noted. We found profound hyposulfatemia due to complete loss of renal sulfate reabsorption. Cholesterol sulfate was reduced. Intravenous N-acetylcysteine administration temporarily restored plasma sulfate levels. We conclude that loss of the SLC13A1 gene leads to profound hypersulfaturia and hyposulfatemia, which is mainly associated with abnormal skeletal development, possibly predisposing to degenerative bone and joint disease. The diagnosis might be easily missed and more frequent.

Vaccine-preventable disease hospitalized patients with heart failure with reduced ejection fraction.

BACKGROUND: Over five million Americans suffer from heart failure (HF), and this is associated with multiple chronic comorbidities and recurrent decompensation. Currently, there is an increased incidence in vaccine-preventable diseases (VPDs). We aim to investigate the impact of HF with reduced ejection fraction (HFrEF) in patients hospitalized with VPDs. HYPOTHESIS: Patient with HFrEF are at higher risk for VPDs and they carry a higher risk for in-hospital complications. METHODS: Retrospective analysis from all hospital admissions from the 2016-2018 National Inpatient Sample (NIS) using the ICD-10CM codes for patients admitted with a primary diagnosis of VPDs with HFrEF and those without reduced ejection fraction. Outcomes evaluated were in-hospital mortality, length of stay (LOS), healthcare utilization, frequency of admissions, and in-hospital complications. Multivariate regression analysis was conducted to adjust for confounders. RESULTS: Out of 317 670 VPDs discharges, we identified 12 130 (3.8%) patients with HFrEF as a comorbidity. The most common admission diagnosis for VPDs was influenza virus (IV) infection (75.0% vs. 64.1%; p < .01), followed by pneumococcal pneumonia (PNA) (13% vs. 9.4%; p < .01). After adjusting for confounders, patients with HFrEF had higher odds of having diagnosis of IV (adjusted [aOR], 1.42; p < .01) and PNA (aOR, 1.27; p < .01). Patients with VPDs and HFrEF had significantly higher odds of mortality (aOR, 1.76; p < .01), LOS, respiratory failure requiring mechanical ventilation, and mechanical ventilation for less than 96 h. CONCLUSION: Influenza and PNA were the most common VPDs admitted to the hospital in patients with a concomitant diagnosis of HFrEF. They were associated with increased mortality and in-hospital complications.

Exercise-induced increase in blood-based brain-derived neurotrophic factor (BDNF) in people with multiple sclerosis: A systematic review and meta-analysis of exercise intervention trials.

BACKGROUND: Exercise training may affect the blood levels of brain-derived neurotrophic factor (BDNF), but meta-analyses have not yet been performed comparing pre- and post-intervention BDNF concentrations in patients with multiple sclerosis (PwMS). OBJECTIVE: To perform a meta-analysis to study the influence of exercise on BDNF levels and define components that modulate them across clinical trials of exercise training in adults living with multiple sclerosis (MS). METHOD: Five databases (PubMed, EMBASE, Cochrane Library, PEDro database, CINAHL) were searched up to June 2021. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, we included 13 articles in the meta-analysis, including 271 subjects. To investigate sources of heterogeneity, subgroup analysis, meta-regression, and sensitivity analysis were conducted. We performed the meta-analysis to compare pre- and post-exercise peripheral levels of BDNF in PwMS. RESULTS: Post-exercise concentrations of serum BDNF were significantly higher than pre-intervention levels (Standardized Mean Difference (SMD): 0.33, 95% CI: [0.04; 0.61], p-value = 0.02). Meta-regression indicated that the quality of the included studies based on the PEDro assessment tool might be a source of heterogeneity, while no significant effect was found for chronological age and disease severity according to the expanded disability status scale. CONCLUSION: This systematic review and meta-analysis shows that physical activity increases peripheral levels of BDNF in PwMS. More research on the effect of different modes of exercise on BDNF levels in PwMS is warranted.

Comparing two identically protocolized, multicentre, randomized controlled trials on caregiver-mediated exercises poststroke: Any differences across countries?

BACKGROUND: The evidence for rehabilitation interventions poststroke lack sufficient robustness. However, variation in treatment effects across countries have been given little attention. OBJECTIVE: To compare two identically protocolized trials conducted in different western countries in order to identify factors that may have caused variation in secondary trial outcomes. METHODS: Comparative study based on individual patient data (N = 129) from two randomized controlled trials, conducted in hospitals and rehabilitation facilities in the Netherlands (N = 66) and Australia (N = 63). Patients with stroke and their caregivers were randomly allocated to an 8-week caregiver-mediated exercises intervention (N = 63; 31 Australian and 32 Dutch) or to a control group (N = 66; 32 Australian and 34 Dutch). Patient characteristics, compliance, usual care and process measures were compared across countries. We examined if study setting significantly moderated the trial outcomes: Hospital Anxiety and Depression Scale, Fatigue Severity Scale and General Self-Efficacy Scale, measured at 8- and 12 weeks follow-up. In addition, we explored if factors that were significantly different across countries caused variation in these trial outcomes. RESULTS: Most patients suffered an ischemic stroke, were in the subacute phase and participated with their partner. Dutch patients were younger (P = 0.005) and had a lower functional status (P = 0.001). Australian patients were recruited earlier poststroke (P<0.001), spent less time in exercise therapy (P<0.001) and had a shorter length of stay (P<0.001). The level of contamination was higher (P = 0.040) among Dutch controls. No effect modification was observed and trial outcomes did not change after controlling for cross-country differences. CONCLUSIONS: The present study highlighted important clinical differences across countries whilst using an identical study protocol. The observed differences could result in a different potential for recovery and variation in treatment effects across trials. We argue that we can proceed faster to evaluating interventions within international pragmatic trials.

Fecal Amino Acid Analysis in Newly Diagnosed Pediatric Inflammatory Bowel Disease: A Multicenter Case-Control Study.

BACKGROUND: Fecal metabolomic profiles differ between pediatric inflammatory bowel disease (IBD) patients and controls and may provide new insights in the pathophysiology of IBD. The role of amino acids, however, is not fully elucidated. We aimed to assess fecal amino acid profiles in pediatric IBD. METHODS: In this case-control study, treatment-naïve, newly diagnosed pediatric IBD patients and a non-IBD control group, matched based on sex and age, were included in 2 tertiary centres. Fecal amino acid profiles were assessed using a targeted high-performance liquid chromatography technique. A random forest classifier method was used to develop a prediction model differentiating IBD from controls and predicting IBD phenotype. The association between IBD localization and amino acid concentrations was tested with ordinal regression models. RESULTS: We included 78 newly diagnosed IBD patients (40 Crohn's disease [CD], 38 ulcerative colitis [UC]) and 105 controls. Patients with IBD could be differentiated from controls with an accuracy of 82% (sensitivity 63%, specificity 97%). Twenty-nine out of the 42 measured unique amino acids were included in the prediction model. Increased levels of tryptophan, taurine, alanine, ornithine, valine, histidine, and leucine were the most differentiating features. Children with CD and UC could be differentiated from the controls with an accuracy of 80% and 90%, respectively. Inflammatory bowel disease phenotype could not be predicted. Tryptophan, valine, and histidine levels were positively associated with more extended disease in UC patients (P < .05). CONCLUSIONS: Fecal amino acids may enhance understanding of the role of host-microbial interactions in the pathophysiology of IBD and may evolve into biomarkers for pediatric IBD diagnostic and personalized medicine.

Fecal amino acid analysis could differentiate newly diagnosed children with IBD from a non-IBD control group with an accuracy of 82%. Increased levels of tryptophan, taurine, alanine, ornithine, and valine were the most differentiating features. This may enhance understanding of IBD pathophysiology.

Acute coronary artery dissection after multiple bee stings.

The occurrence of an acute coronary syndrome following an anaphylactic or anaphylactoid reaction is known as Kounis syndrome. Previous reports of Kounis syndrome described an acute coronary syndrome due either to vasospasm or atherosclerotic rupture of a coronary artery in the presence of cutaneous manifestation from the anaphylactic reaction. We report a case of a 33-year-old man who presented with anterior wall acute myocardial infarction immediately after honeybee stings without the presence of cutaneous manifestations other than the bee sting lesions. Emergent coronary arteriography revealed dissection of the proximal left anterior descending artery, which was treated with balloon dilation with an excellent outcome.

Physical activity dimensions after stroke: patterns and relation with lower limb motor function.

BACKGROUND: Stroke survivors show deteriorated physical functioning and physical activity levels. Physical activity levels of stroke survivors are generally low. It is increasingly recognized that physical activity is a multidimensional construct that cannot be captured in a single outcome. In-depth insight into multidimensional physical activity patterns may guide the development and timing of targeted rehabilitation interventions. This longitudinal cohort study explored how multidimensional physical activity outcomes develop during recovery in the subacute phase after stroke and if changes in physical activity were correlated to recovery of lower limb motor function. METHODS: Patients were recruited during inpatient rehabilitation. At 3, 12, and 26 weeks post-onset, motor function was measured by the Fugl-Meyer Lower Extremity Assessment (FMA-LE). Physical activity was measured with the Activ8 accelerometer in multiple outcomes: counts per minute during walking (CPMwalking; a measure of Intensity), number of active bouts (Frequency), mean length of active bouts (Distribution) and % of waking time in upright positions (Duration). Generalized estimating equations (GEE) were used to study changes in physical activity over time and the relation with the change in lower limb motor recovery. RESULTS: Thirty-nine patients (age 56 ± 9, 77% male, 89% ischemic stroke) were included. GEE models showed a significant main effect of time for PA Intensity (+ 13%, p = 0.007) and Duration (+ 64%, p = 0.012) between 3 and 12 weeks. Motor function did not show a significant effect in all PA models across the 3 timepoints (p > 0.020). A significant interaction effect of time × motor function was observed (p < 0.001). CONCLUSIONS: Patterns of PA recovery depend on the PA dimensions: PA Intensity and Duration increased mostly between 3 and 12 weeks post-stroke, whereas Frequency and Distribution did not show substantial changes. Further, no strong associations with motor recovery and high inter-individual variability were documented, which underlies the need to consider factors specific to the disease, the individual patient and the context.

The Cortical Response Evoked by Robotic Wrist Perturbations Reflects Level of Proprioceptive Impairment After Stroke.

Background: Proprioception is important for regaining motor function in the paretic upper extremity after stroke. However, clinical assessments of proprioception are subjective and require verbal responses from the patient to applied proprioceptive stimuli. Cortical responses evoked by robotic wrist perturbations and measured by electroencephalography (EEG) may be an objective method to support current clinical assessments of proprioception. Objective: To establish whether evoked cortical responses reflect proprioceptive deficits as assessed by clinical scales and whether they predict upper extremity motor function at 26 weeks after stroke. Methods: Thirty-one patients with stroke were included. In week 1, 3, 5, 12, and 26 after stroke, the upper extremity sections of the Erasmus modified Nottingham Sensory Assessment (EmNSA-UE) and the Fugl-Meyer Motor Assessment (FM-UE) and the EEG responses (64 channels) to robotic wrist perturbations were measured. The extent to which proprioceptive input was conveyed to the affected hemisphere was estimated by the signal-to-noise ratio (SNR) of the evoked response. The relationships between SNR and EmNSA-UE as well as SNR and time after stroke were investigated using linear regression. Receiver-operating-characteristic curves were used to compare the predictive values of SNR and EmNSA-UE for predicting whether patients regained some selective motor control (FM-UE > 22) or whether they could only move their paretic upper extremity within basic limb synergies (FM-UE ≤ 22) at 26 weeks after stroke. Results: Patients (N = 7) with impaired proprioception (EmNSA-UE proprioception score < 8) had significantly smaller SNR than patients with unimpaired proprioception (N = 24) [EmNSA-UE proprioception score = 8, t(29) = 2.36, p = 0.03]. No significant effect of time after stroke on SNR was observed. Furthermore, there was no significant difference in the predictive value between EmNSA-UE and SNR for predicting motor function at 26 weeks after stroke. Conclusion: The SNR of the evoked cortical response does not significantly change as a function of time after stroke and differs between patients with clinically assessed impaired and unimpaired proprioception, suggesting that SNR reflects persistent damage to proprioceptive pathways. A similar predictive value with respect to EmNSA-UE suggests that SNR may be used as an objective predictor next to clinical sensory assessments for predicting motor function at 26 weeks after stroke.

Symptom dimensions of anxiety in Parkinson's disease: Replication study in a neuropsychiatric patient population.

INTRODUCTION: Anxiety disorders occur in approximately one third of people with Parkinson's disease (PD), and have a major impact on patient and caregiver wellbeing. In order to better understand and diagnose anxiety in PD patients, we investigated the generalizability of the results of a previous factor analysis on anxiety symptoms to a sample of PD patients with neuropsychiatric symptoms. METHODS: In this cross-sectional study, anxiety symptoms were measured with the Beck Anxiety Inventory (BAI) in 123 PD patients who were referred for neuropsychiatric diagnostics and treatment. Subscales of anxiety were analyzed through principal component analysis of BAI items. The associations between BAI subscales and symptoms of motor and cognitive function and depression were assessed through regression analyses. RESULTS: Similar to the previous factor analysis, we found one psychological (affective) and four somatic subscales of anxiety in the BAI. The affective subscale was the principal component explaining 35.9% of the variance. The scores on the total BAI and the affective subscale were significantly associated with depressive symptoms. In a post-hoc analysis, the affective subscale had equal power as compared to the total BAI in predicting whether or not participants were diagnosed with an anxiety disorder after psychiatric evaluation. CONCLUSION: In this study, we replicated our previous findings of one affective and multiple somatic subscales of the BAI. The 7-item affective subscale of the BAI shows potential as a screening tool for non-episodic anxiety in PD. However, in clinical practice, we recommend evaluating anxiety symptoms in the context of other PD symptoms, including motor, autonomic, and other (neuro)psychiatric symptoms.

Smoothness metrics for reaching performance after stroke. Part 1: which one to choose?

BACKGROUND: Smoothness is commonly used for measuring movement quality of the upper paretic limb during reaching tasks after stroke. Many different smoothness metrics have been used in stroke research, but a 'valid' metric has not been identified. A systematic review and subsequent rigorous analysis of smoothness metrics used in stroke research, in terms of their mathematical definitions and response to simulated perturbations, is needed to conclude whether they are valid for measuring smoothness. Our objective was to provide a recommendation for metrics that reflect smoothness after stroke based on: (1) a systematic review of smoothness metrics for reaching used in stroke research, (2) the mathematical description of the metrics, and (3) the response of metrics to simulated changes associated with smoothness deficits in the reaching profile. METHODS: The systematic review was performed by screening electronic databases using combined keyword groups Stroke, Reaching and Smoothness. Subsequently, each metric identified was assessed with mathematical criteria regarding smoothness: (a) being dimensionless, (b) being reproducible, (c) being based on rate of change of position, and (d) not being a linear transform of other smoothness metrics. The resulting metrics were tested for their response to simulated changes in reaching using models of velocity profiles with varying reaching distances and durations, harmonic disturbances, noise, and sub-movements. Two reaching tasks were simulated; reach-to-point and reach-to-grasp. The metrics that responded as expected in all simulation analyses were considered to be valid. RESULTS: The systematic review identified 32 different smoothness metrics, 17 of which were excluded based on mathematical criteria, and 13 more as they did not respond as expected in all simulation analyses. Eventually, we found that, for reach-to-point and reach-to-grasp movements, only Spectral Arc Length (SPARC) was found to be a valid metric. CONCLUSIONS: Based on this systematic review and simulation analyses, we recommend the use of SPARC as a valid smoothness metric in both reach-to-point and reach-to-grasp tasks of the upper limb after stroke. However, further research is needed to understand the time course of smoothness measured with SPARC for the upper limb early post stroke, preferably in longitudinal studies.

Smoothness metric during reach-to-grasp after stroke: part 2. longitudinal association with motor impairment.

BACKGROUND: The cause of smoothness deficits as a proxy for quality of movement post stroke is currently unclear. Previous simulation analyses showed that spectral arc length (SPARC) is a valid metric for investigating smoothness during a multi-joint goal-directed reaching task. The goal of this observational study was to investigate how SPARC values change over time, and whether SPARC is longitudinally associated with the recovery from motor impairments reflected by the Fugl-Meyer motor assessment of the upper extremity (FM-UE) in the first 6 months after stroke. METHODS: Forty patients who suffered a first-ever unilateral ischemic stroke (22 males, aged 58.6 ± 12.5 years) with upper extremity paresis underwent kinematic and clinical measurements in weeks 1, 2, 3, 4, 5, 8, 12, and 26 post stroke. Clinical measures included amongst others FM-UE. SPARC was obtained by three-dimensional kinematic measurements using an electromagnetic motion tracking system during a reach-to-grasp movement. Kinematic assessments of 12 healthy, age-matched individuals served as reference. Longitudinal linear mixed model analyses were performed to determine SPARC change over time, compare smoothness in patients with reference values of healthy individuals, and establish the longitudinal association between SPARC and FM-UE scores. RESULTS: SPARC showed a significant positive longitudinal association with FM-UE (B: 31.73, 95%-CI: [27.27 36.20], P < 0.001), which encompassed significant within- and between-subject effects (B: 30.85, 95%-CI: [26.28 35.41], P < 0.001 and B: 50.59, 95%-CI: [29.97 71.21], P < 0.001, respectively). Until 5 weeks post stroke, progress of time contributed significantly to the increase in SPARC and FM-UE scores (P < 0.05), whereafter they levelled off. At group level, smoothness was lower in patients who suffered a stroke compared to healthy subjects at all time points (P < 0.05). CONCLUSIONS: The present findings show that, after stroke, recovery of smoothness in a multi-joint reaching task and recovery from motor impairments are longitudinally associated and follow a similar time course. This suggests that the reduction of smoothness deficits quantified by SPARC is a proper objective reflection of recovery from motor impairment, as reflected by FM-UE, probably driven by a common underlying process of spontaneous neurological recovery early post stroke.