Estimating motor progression trajectory pursuant to temporal dynamic status of cardiac denervation in Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is a multifaceted disease that encompasses diverse clinical phenotypes. The diversity of PD could be subtyped based on the temporal dynamic status of cardiac sympathetic innervation; (1) initially, denervated myocardium (peripheral nervous system-predominant; PNS-predominant), (2) preserved myocardium (central nervous system-predominant; CNS-predominant), and (3) preserved myocardium who developed cardiac sympathetic denervation (CSD) on the subsequent imaging (Converter; delayed cardiac denervation). This study assessed how the cardiac denervation could reflect the pathobiology. We investigated whether this phenotyping could help predict the motor progression trajectory of PD.

METHODS

Cardiac sympathetic innervation was evaluated using initial and sequential 123I-meta-iodobenzylguanidine myocardial scintigraphy and patients were stratified into three groups as above. Motor severity and progression were evaluated in each patient. The association between subtypes and dopaminergic nigrostriatal degeneration was analyzed. The influence of cardiac denervation on motor progression was also investigated.

RESULTS

Among the enrolled 195 patients, 144 PD subjects were defined as PNS-predominant, 16 as Converter, and 35 as CNS-predominant. The most severe nigrostriatal degeneration was observed in the PNS-predominant group and the dopaminergic degeneration was the most asymmetric in the CNS-predominant group. Positive linear trends of nigrostriatal degeneration and its asymmetric degeneration of striatum and globus pallidus were found across the patterns of cardiac sympathetic innervation (PNS-predominant vs. Converter vs. CNS-predominant). It indicated an increasing degree of asymmetric degeneration among the groups. A longitudinal estimation of motor progression revealed distinct cardiac denervation trajectories for each subtype.

CONCLUSIONS

These results implicated that the subtypes of CSD might indicate a predominant origin and spreading pattern of pathobiology.

Fasting Plasma Glucose Levels and Longitudinal Motor and Cognitive Outcomes in Parkinson's Disease Patients

OBJECTIVE

Hyperglycemia and diabetes mellitus have been identified as poor prognostic factors for motor and nonmotor outcomes in patients with Parkinson's disease (PD), although there is some controversy with this finding. In the present study, we investigated the effects of fasting plasma glucose (FPG) levels on longitudinal motor and cognitive outcomes in PD patients.

METHODS

We included a total of 201 patients who were diagnosed with PD between January 2015 and January 2020. The patients were categorized based on FPG level into euglycemia (70 mg/dL < FPG < 100 mg/dL), intermediate glycemia (100 mg/dL ≤ FPG < 126 mg/dL), and hyperglycemia (FPG ≥ 126 mg/dL), and longitudinal FPG trajectories were analyzed using group-based trajectory modeling. Survival analysis was conducted to determine the time until motor outcome (Hoehn and Yahr stage ≥ 2) and the conversion from normal cognition to mild cognitive impairment.

RESULTS

Among the patient cohort, 82 had euglycemia, 93 had intermediate glycemia, and 26 had hyperglycemia. Intermediate glycemia (hazard ratio 1.747, 95% confidence interval [CI] 1.083-2.816, p = 0.0221) and hyperglycemia (hazard ratio 3.864, 95% CI 1.996-7.481, p < 0.0001) were found to be significant predictors of worsening motor symptoms. However, neither intermediate glycemia (hazard ratio 1.183, 95% CI 0.697-2.009, p = 0.5339) nor hyperglycemia (hazard ratio 1.297, 95% CI 0.601-2.800, p = 0.5078) demonstrated associations with the longitudinal progression of cognitive impairment. Diabetes mellitus, defined by self-reported medical history, was not related to poor motor or cognitive impairment outcomes.

CONCLUSION

Our.

RESULTS

suggest that both impaired glucose tolerance and hyperglycemia could be associated with motor progression in PD patients.

Correlation of olfactory function factors with cardiac sympathetic denervation in Parkinson's disease

BACKGROUND

Hyposmia is a common nonmotor symptom of Parkinson's disease (PD) and reportedly associated with dysautonomia in PD. The smell identification test for measuring olfactory function consists of multiple items to discriminate specific scents. In the present study, factor analysis of the smell identification test was performed, and the correlation of extracted factors with cardiac sympathetic denervation (CSD) in patients with PD was investigated.

METHODS

The present study included 183 early PD patients who underwent the Cross-Cultural Smell Identification Test (CC-SIT) and 123I-meta-iodobenzylguanidine (123I-MIBG) myocardial scintigraphy. Factor analysis of 12 items on the CC-SIT was performed using the computed correlation matrix for the binary items, and five smell factors were extracted. Multiple linear regression was performed to determine the correlation of olfactory function with late heart-to-mediastinum (H/M) ratio of 123I-MIBG uptake.

RESULTS

The mean CC-SIT score was 6.1 ± 2.6, and 133 patients (72.7%) had CSD. The CC-SIT score and five smell factors were not associated with dopamine transporter uptake or cognitive functions. However, the CC-SIT score significantly correlated with age (P < 0.001) and late H/M ratio (P < 0.001). Factors 1 and 5 showed an increasing trend with larger H/M ratio, although it was not statistically significant (β = 0.203, P = 0.085 and β = 0.230, P = 0.085, respectively). Factor 5 significantly correlated with the H/M ratio in PD patients with CSD (β = 0.676, P = 0.036).

DISCUSSION

The results showed olfactory dysfunction to be selectively associated with cardiac sympathetic burden in PD. The correlation of certain factors with CSD indicates the possibility of selective hyposmia in PD patients.

Cardiac sympathetic "morbidity" might reflect the neurobiology of early Parkinson's disease

BACKGROUND

An appropriate extracranial biomarker that delineates endophenotypes of Parkinson's disease (PD) at an early stage and reflects the neurodegenerative process is lacking. An evaluation of myocardial sympathetic nerve terminals could be a good candidate. This study aimed to explore subtypes of PD patients that showed cardiac catecholaminergic vesicular defect and their characteristics.

METHODS

This study included 122 early drug-naïve PD patients who were followed for approximately 4-5 years. All patients were examined with 18F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane positron-emission tomography and 123I-meta-iodobenzylguanidine myocardial scintigraphy. Cardiac scans were reexamined two or three times. Patients were subgrouped into the sympathetic denervated group at the initial scan, those without evidence of denervated myocardium in the first and subsequent scans, and the converters whose myocardium was initially normal but became impaired in the subsequent scans. Cognition in 99 patients was initially assessed with neuropsychological tests. Any associations between cardiac denervation subtypes and presynaptic dopamine transporter densities were investigated. Cognitive status relevant to cardiac sympathetic denervation status was evaluated.

RESULTS

This study found that cross-sectional comparisons of presynaptic monoamine transporter availability with a predefined order of cardiac denervation groups revealed parallel degeneration. A quadratic correlation between cardiac catecholamine capacity and cognition was observed. This association was interpreted to reflect the early neurobiology of PD.

CONCLUSION

An observed cardiac catecholaminergic gradient was to mirror the central neurobiology of early PD.

Risk of epilepsy in gonadal teratoma: a nationwide population-based study

Epilepsy is a common neurological disease. Systemic tumors are associated with an increased risk of epileptic events. Paraneoplastic encephalitis related to gonadal teratoma is frequently accompanied by seizures and life-threatening status epilepticus (SE). However, the risk of epilepsy in gonadal teratoma has not been studied. This study aims to investigate the relationship between epileptic events and gonadal teratoma. This retrospective cohort study used the Korean National Health Insurance (KNHI) database. The study population was divided into two study arms (ovarian teratoma vs. control and testicular teratoma vs. control) with 1:2 age and gender-matched control groups without a history of gonadal teratoma or other malignancy. Participants with other malignancies, neurologic disorders, and metastatic brain lesions were excluded. We observed the occurrence of epileptic events during the observation period (2013-2018) and investigated the risk of epileptic events in each gonadal teratoma group compared to controls. In addition, the influence of malignancy and tumor removal was investigated. The final analysis included 94,203 women with ovarian teratoma, 2314 men with testicular teratoma, and controls. Ovarian teratoma is associated with a higher risk of epilepsy without SE (HR, 1.244; 95% CI 1.112-1.391) and epilepsy with SE (HR, 2.012; 95% CI 1.220-3.318) compared to the control group. The risk of epilepsy without SE was higher in malignant ovarian teratoma (HR, 1.661; 95% CI 1.358-2.033) than in benign (HR, 1.172; 95% CI 1.037-1.324). Testicular teratoma did not show significant relations with epileptic events. The risk of epileptic events showed a tendency to decrease after removing the ovarian teratoma. This study found that ovarian teratoma is associated with a higher risk of epileptic events, especially in malignant tumors, whereas testicular teratoma did not show significant differences in epileptic events compared to the control group. This study adds to the current understanding of the association between gonadal teratoma and epileptic events.

A 3-year natural history of orthostatic blood pressure dysregulation in early Parkinson's disease

In Parkinson's disease (PD), cardiovascular dysautonomia accumulates with disease progression, but studies are lacking on the natural history behind each subtype except orthostatic hypotension. This study investigated the early natural history of orthostatic blood pressure (BP) subtypes in PD. Two hundred sixty-seven early PD patients were included. Their cardiovascular functions were assessed by head-up tilt-test and ¹²³I-metaiodobenzylguanidine scintigraphy. All patients were classified as having supine hypertension (SH), orthostatic hypertension (OHT), delayed orthostatic hypotension (dOH), or orthostatic hypotension (OH) according to consensus criteria. The patients were assigned to one of three groups: extreme BP dysregulation (BP_extreme), mild BP dysregulation (BP_mild), and no BP dysregulation (BP_none) according to their orthostatic BP subtypes. The autonomic functions of 237 patients were re-assessed after approximately 3 years. Among initially enrolled subjects, 61.8% of the patients showed orthostatic BP dysregulation: 29.6% in the BP_extreme group and 32.2% in the BP_mild group. At follow-up, the BP_extreme group increased in number, while the BP_mild group diminished. Two-thirds of the initial BP_extreme patients maintained their initial subtype at follow-up. In comparison, 40.7% of the initial BP_mild patients progressed to the BP_extreme group, and 32.4% and 14.7% of the initial BP_none group progressed to BP_extreme and BP_mild groups, respectively. Cardiac denervation was most severe in the BP_extreme group, and a linear gradient of impairment was observed across the subtypes. In conclusion, various forms of positional BP dysregulation were observed during the early disease stage. SH and OH increased with disease progression, while OHT and dOH decreased, converting primarily to SH and/or OH.

Obstructive Sleep Apnea and Striatal Dopamine Availability in Parkinson's Disease

BACKGROUND

Sleep disorders are frequently associated with Parkinson's disease. Obstructive sleep apnea syndrome is one of these sleep disorders and is associated with the severity of motor symptoms in Parkinson's disease. Obstructive sleep apnea can lead to dopaminergic neuronal cell degeneration and may impair the clearance of α-synuclein in Parkinson's disease. Striatal dopamine uptake is a surrogate marker of nigral dopaminergic cell damage.

OBJECTIVE

We aimed to investigate the differences in striatal dopamine availability between Parkinson's disease patients with or without obstructive sleep apnea.

METHODS

A total of 85 de novo and nonmedicated Parkinson's disease patients were enrolled. Full-night polysomnography was performed for all patients, and obstructive sleep apnea was diagnosed as apnea/hypopnea index ≥5. Positron emission tomography was performed with 18 F-N-(3-fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) nortropane, and the regional standardized-uptake values were analyzed using a volume-of-interest template and compared between groups with or without obstructive sleep apnea.

RESULTS

Dopamine availability in the caudate nucleus of the obstructive sleep apnea group was significantly lower than that of the nonobstructive sleep apnea group. On subgroup analysis, such association was found in female but not in male patients. In other structures (putamen, globus pallidus, and thalamus), dopamine availability did not differ between the two groups.

CONCLUSION

This study supports the proposition that obstructive sleep apnea can contribute to reduced striatal dopamine transporter availability in Parkinson's disease. Additional studies are needed to assess the causal association between obstructive sleep apnea and the neurodegenerative process in Parkinson's disease. © 2023 International Parkinson and Movement Disorder Society.

Validity and Reliability of the Korean-Translated Version of the International Cooperative Ataxia Rating Scale in Cerebellar Ataxia

OBJECTIVE

The International Cooperative Ataxia Rating Scale (ICARS) is a semiquantitative clinical scale for ataxia that is widely used in numerous countries. The purpose of this study was to investigate the validity and reliability of the Korean-translated version of the ICARS.

METHODS

Eighty-eight patients who presented with cerebellar ataxia were enrolled. We investigated the construct validity using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). We also investigated the internal consistency using Cronbach's α and intrarater and interrater reliability using intraclass correlation coefficients.

RESULTS

The Korean-translated ICARS showed satisfactory construct validity using EFA and CFA. It also revealed good interrater and intrarater reliability and showed acceptable internal consistency. However, subscale 4 for assessing oculomotor disorder showed moderate internal consistency.

CONCLUSION

This is the first report to investigate the validity and reliability of the Korean-translated ICARS. Our results showed excellent construct and convergent validity. The reliability is also acceptable.

Low serum complement level is associated with higher mortality in tuberculous meningitis: a retrospective cohort study

Purpose

We evaluated the associations between serum complement levels and tuberculous meningitis (TBM), bacterial meningitis (BM), and viral meningitis (VM), as well as the association between serum complement levels and mortality in TBM.

Methods

Background information and blood/cerebrospinal fluid analysis results were collected from 2009 to 2019. Patients who had serum complement level data collected at admission and who were diagnosed with TBM (n = 97), BM (n = 31), or VM (n = 557) were enrolled.

Results

Initial serum complement levels were significantly lower in the TBM group than the VM group in both the total population and the propensity score-matched population. In the TBM and VM groups, compared to patients with initial highest-quartile C4 level, patients in the lowest quartile (C4 < 24.3 mg/dL) had significantly greater odds of TBM diagnosis (odds ratio, 2.2; 95% confidence interval, 1.0-4.5; p = 0.038). In the TBM group, patients with the lowest-quartile C3 level (<96.9 mg/dL) experienced a significantly higher 90-day mortality rate compared to other TBM patients (hazard ratio, 19.0; 95% confidence interval, 2.1-167.4.5; p = 0.008).

Conclusion

Both serum C3 and C4 levels were significantly lower in the TBM group than in the VM group. TBM patients with lower serum C3 level had a significantly higher mortality rate than those with higher C3 level.

Caudate-anchored cognitive connectivity pursuant to orthostatic hypotension in early Parkinson's disease

¹⁸F-Florbetaben is a tracer used to evaluate the metabolic activity of and amyloid accumulation in the brain when measured in early- and late-phase, respectively. The metabolism of neural substrates could be viewed as a network and might be an important factor in cognition. Orthostatic hypotension (OH) might play an indirect moderating role in cognition, and its latent influence could modify the inherent cognitive network. This study aimed to identify changes of cognitive connectivity according to orthostatic stress in patients with early Parkinson's disease (PD). This study included 104 early PD patients who were evaluated with a head-up tilt-test and¹⁸F-Florbetaben positron emission tomography (PET). Cognition was assessed with a comprehensive neuropsychological battery that gauged attention/working memory, language, visuospatial, memory, and executive functions. PET images were analyzed visually for amyloid deposits, and early-phase images were normalized to obtain standardized uptake ratios (SUVRs) of pre-specified subregions relevant to specific cognitive domains. The caudate nucleus was referenced and paired to these pre-specified regions. The correlations between SUVRs of these regions were assessed and stratified according to presence of orthostatic hypotension. Among the patients studied, 22 (21.2%) participants had orthostatic hypotension. Nineteen patients (18.3%) were positive for amyloid-β accumulation upon visual analysis. Moderate correlations between the caudate and pre-specified subregions were observed (Spearman's rho, range [0.331-0.545]). Cognition did not differ, but the patterns of correlation were altered when the disease was stratified by presence of orthostatic stress. In conclusion, cognition in early PD responds to hemodynamic stress by adapting its neural connections between regions relevant to cognitive functions.

Cardiac sympathetic denervation could be associated with dysphagia in Parkinson's disease

Background

Dysphagia is an important non-motor symptom that is closely associated with quality of living and mortality in Parkinson's disease (PD). However, the pathophysiology of dysphagia in PD remains inconclusive. We tried to confirm whether the occurrence of dysphagia could be related to sympathetic degeneration using cardiac 123I-metaiodobenzylguanidine (MIBG) scintigraphy.

Methods

We prospectively recruited 27 PD patients and classified them into two groups (PD with dysphagia vs. PD without dysphagia) by Swallowing Disturbance Questionnaire (SDQ) score and compared the clinical characteristics, videofluoroscopic swallowing study (VFSS) findings and parameters from cardiac MIBG scintigraphy.

Results

The mean early and late H/M ratios were significantly lower in the PD with dysphagia group than those in the PD without dysphagia group (1.39 ± 0.21 vs. 1.86 ± 0.21, p &lt; 0.01; 1.26 ± 0.18 vs. 1.82 ± 0.29, p &lt; 0.01). In the correlation analysis, both the early and late H/M ratios were negatively correlated with the SDQ score and total VDS score (r = −0.65, p &lt; 0.01; r = −0.53, p &lt; 0.01; r = −0.65, p &lt; 0.01, r = −0.58, p &lt; 0.01).

Conclusion

We confirmed that cardiac sympathetic denervation might be associated with the presence and severity of dysphagia. This finding indicates that dysphagia in PD could be associated with a nondopaminergic mechanism.

Premorbid cancer and motor reserve in patients with Parkinson's disease

Decreased cancer risk has been reported in patients with Parkinson’s disease (PD), and cancer prior to PD can have a protective effect on PD risk. We investigated cancer history prior to PD diagnosis to determine if such history can enhance motor reserve in PD by assessing the association between motor deficits and striatal subregional dopamine depletion. A total of 428 newly diagnosed, drug-naïve PD patients was included in the study. PD patients were categorized into three groups of no prior neoplasia, premorbid precancerous condition, and premorbid malignant cancer before PD diagnosis. Parkinsonian motor status was assessed using the Unified Parkinson’s Disease Rating Scale (UPDRS) motor score and modified Hoehn and Yahr stage score. All patients underwent positron emission tomography (PET) with ¹⁸F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane (¹⁸F-FP-CIT), and the regional standardized uptake value ratios (SUVRs) were analyzed with a volume-of-interest template among the groups. The UPDRS motor score negatively correlated with SUVRs in the posterior putamen for all patient groups. Groups with neoplasia, especially those with premorbid cancer, showed lower motor scores despite similar levels of dopamine depletion in the posterior putamen relative to those without neoplasia. These results suggest that premorbid cancer acts as a surrogate for motor reserve in patients with PD and provide imaging evidence that history of cancer has a protective effect on PD.

Decreased thalamic monoamine availability in drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is caused by a dopamine receptor blockade and is a major cause of misleading diagnosis of Parkinson’s disease (PD). Striatal dopamine activity has been investigated widely in DIP; however, most studies with dopamine transporter imaging have focused on the clinical characteristics and prognosis. This study investigated differences in striatal subregional monoamine availability among patients with DIP, normal controls, and patients with early PD. Thirty-five DIP patients, the same number of age-matched PD patients, and 46 healthy controls were selected for this study. Parkinsonian motor status was examined. Brain magnetic resonance imaging and positron emission tomography with ¹⁸F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane were performed, and the regional standardized uptake values were analyzed with a volume-of-interest template and compared among the groups. The groups were evenly matched for age, but there were numerically more females in the DIP group. Parkinsonian motor symptoms were similar in the DIP and PD groups. Monoamine availability in the thalamus of the DIP group was lower than that of the normal controls and similar to that of the PD group. In other subregions (putamen, globus pallidus, and ventral striatum), monoamine availability in the DIP group and normal controls did not differ and was higher than that in the PD group. This difference compared to healthy subject suggests that low monoamine availability in the thalamus could be an imaging biomarker of DIP.

The Association of β-Amyloid with Cognition and Striatal Dopamine in Early, Non-Demented Parkinson's Disease

BACKGROUND

Co-occurrence of β-amyloid (Aβ) pathology has been reported in Parkinson's disease (PD), and Aβ deposition in the brain may contribute to cognitive decline in patients with PD. Whether striatal dopamine uptake and cognitive status differ with amyloid deposition has been reported in only a few studies.

OBJECTIVE

The purpose of this study was to investigate the association among striatal dopaminergic availability, Aβ-positivity, and motor and cognitive status in early and non-demented PD.

METHODS

A total of 98 newly-diagnosed, non-medicated, and non-demented patients with PD were included in this study. Cognitive status was assessed using neuropsychological testing. Patients with mild cognitive impairment (MCI) were stratified into two groups: amnestic MCI (aMCI) and non-amnestic MCI (naMCI). Patient motor status was examined using the Unified Parkinson's Disease Rating Scale (UPDRS) and positron emission tomography (PET) with 18F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane (18F-FP-CIT). All patients also underwent 18F-florbetaben (18F-FBB) PET and were divided based on the results into Aβ-positive and Aβ-negative groups.

RESULTS

Eighteen patients had Aβ-positivity in 18F-FBB PET and 67 had MCI. Sixteen of 18 with Aβ-positive patients had MCI. The Aβ-positive group had higher frequency of MCI, especially amnestic-type, and lower dopaminergic activities in the left ventral striatum, but not with UPDRS motor score.

CONCLUSION

Amyloid pathology was associated with MCI, especially amnestic-subtype, in early and non-demented PD patients and with low dopaminergic activities in the left ventral striatum. This finding suggests that PD patients with Aβ-positivity have AD-related cognitive pathophysiology in PD and associated impaired dopaminergic availability in the ventral striatum can affect the pathophysiology in various ways.

Selective multi-nanosoldering for fabrication of advanced solution-processed micro/nanoscale metal grid structures

Solution-processed metal grid transparent conductors with low sheet resistance, high optical transmittance and good mechanical flexibility have great potential for use in flexible optoelectronic devices. However, there are still remaining challenges to improve optoelectrical properties and electromechanical stability of the metallic structures due to random loose packings of nanoparticles and the existence of many pores. Here we introduce a selective multi-nanosoldering method to generate robust metallic layers on the thin metal grid structures (< a thickness of 200 nm), which are generated via self-pining assisted direct inking of silver ions. The selective multi-nanosoldering leads to lowering the sheet resistance of the metal grid transparent conductors, while keeping the optical transmittance constant. Also, it reinforces the electromechanical stability of flexible metal grid transparent conductors against a small bending radius or a repeated loading. Finally, organic light-emitting diodes based on the flexible metal grid transparent conductors are demonstrated. Our approach can open a new route to enhance the functionality of metallic structures fabricated using a variety of solution-processed metal patterning methods for next-generation optoelectronic and micro/nanoelectronic applications.

The Impact of Impulsivity on Quality of Life in Early Drug-Naïve Parkinson's Disease Patients

Objective

Impulse control disorders (ICDs) in Parkinson’s disease (PD) are mostly related to dopamine replacement therapy (DRT); however, drug-naïve PD patients have also frequently experienced impulsivity. This phenomenon makes clinicians hesitate treating patients with DRT. In this study, we assessed the effect of impulsivity on quality of life (QOL) in drug-naïve PD patients.

Methods

Two hundred three newly diagnosed, nonmedicated PD patients were enrolled, and they received structured clinical interviews, physical examinations and validated questionnaires to evaluate motor and nonmotor symptoms and QOL. Impulsivity was evaluated using the Questionnaire for Impulsive-Compulsive Disorders in Parkinson’s Disease-Rating Scale (QUIP-RS).

Results

Thirty-eight patients (18.7%) had impulsivity with QUIP-RS scores ≥ 1 and 4 patients (2.0%) were diagnosed with combined ICDs. Motor and nonmotor symptoms were significantly correlated with the Parkinson’s Disease Questionnaire-39 summary index. Female sex and QUIP-RS scores were also correlated with QOL in drug-naïve PD patients.

Conclusion

The results of the present study showed that impulsivity negatively influences QOL in early drug-naïve PD patients. In addition, more severe motor and nonmotor symptoms were also associated with lower QOL. Such findings complicate treatment but provide valuable information for managing early PD.

"Depressed" caudate and ventral striatum dopamine transporter availability in de novo Depressed Parkinson's disease

Depression can occur before the onset of motor symptoms in Parkinson's disease (PD) patients. The pathophysiology of depression in PD involves various brain regions and relevant functional circuits. This study investigated whether there exist distinctive patterns of presynaptic monoamine transporter densities in the basal ganglia depending on the degree of depression in patients with PD. A total of 123 early and drug-naïve PD patients were enrolled. Their affective status was evaluated by the Montgomery-Asberg Depression Rating Scale (MADRS), and subjects were subgrouped into one of the following three groups according to their MADRS scores: no depression, mild depression, and moderate-to-severe depression. All patients underwent positron emission tomography (PET) using ¹⁸F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane. The PET images were normalized, and differences in the regional standardized uptake value ratios (SUVRs) for each side of the caudate, putamen, globus pallidus, thalamus, and ventral striatum were analyzed and compared between the three groups. A trend analysis was performed across the groups to discern any associations between SUVR values of the basal ganglia and depression severity. The SUVR values of the caudate, anterior caudate nuclei, and ventral striatum declined as MADRS increased. The SUVR values of the striatum showed an inverse dose-dependent trend of antero- and ventroposterior gradient across the groups. This result indirectly revealed the involvement of the associative and limbic circuitry of the brain that are modulated by monoamines in early PD with depression. This might suggest an in vivo causal relationship between the ventral striatum, caudate and depression.

Trouble Concentrating is an Easily Overlooked Symptom of Orthostatic Hypotension in Early Parkinson's Disease

BACKGROUND

Trouble concentrating during orthostasis is one symptom of orthostatic hypotension (OH), but it is often ignored in clinical practice because OH incorporates many nonspecific symptoms. Blunted cognition during orthostasis may affect various aspects of the clinical status of patients with Parkinson's disease (PD), but its impact on drug-naïve, early PD patients is not clear.

OBJECTIVE

This study investigated the association between trouble concentrating during orthostasis and orthostatic blood pressure changes and the influence of trouble concentrating during orthostasis on other non-motor symptoms and health-related quality of life in de novo PD.

METHODS

A total of 124 patients with early PD were enrolled and received a structured clinical interview, physical examination, and validated questionnaires to evaluate motor and non-motor symptoms and quality of life. Disturbed concentration was evaluated with question 5 of the Orthostatic Hypotension Questionnaire system assessment (part I). Supine blood pressure and blood pressure change during tilt table testing were recorded, and any association was analyzed.

RESULTS

Among the study population, 76 (61.3%) patients had trouble concentrating. Patients with blunted concentration had a steeper decrease in blood pressure during orthostasis. The score for trouble concentrating was positively associated with non-motor symptoms and quality of life scores.

CONCLUSIONS

Trouble concentrating when standing was a frequent finding in early, drug-naïve PD patients. It was positively associated with non-motor burden, mood and quality of life in patients with PD. OH was correlated with the incidence of trouble concentrating. Such findings complicate treatment but provide valuable information for managing early PD.

Excessive daytime sleepiness and its impact on quality of life in de novo Parkinson's disease

Excessive daytime sleepiness (EDS) is one of the most common sleep problems in patients with Parkinson's disease (PD); however, its clinical implications are not clear, especially in early stage, non-medicated PD patients. This study investigated EDS in Korean patients with de novo PD and its impact on quality of life. This cross-sectional study was carried out with 198 PD patients who underwent a structured clinical interview and examination based on common and conventional scales. Motor and nonmotor symptoms were assessed by the Unified Parkinson's Disease Rating Scale (UPDRS) and Non-Motor Symptoms Scale (NMSS). EDS was evaluated with the Epworth Sleepiness Scale (ESS), the nocturnal disabilities and nighttime sleep problems were assessed with Parkinson's Disease Sleep Scale 2nd version, and quality of life was measured with the Parkinson's Disease Quality of Life 39 (PDQ-39). The relationships between ESS score and each scale were investigated. Among the patients studied, 42 patients had EDS defined as ESS > 10. Patients with EDS had a higher motor burden, greater nocturnal disabilities, more severe non-motor symptoms, and lower quality of life than did patients without EDS. Partial correlations revealed that ESS score was related to PDQ-39 summary index, irrespective of age, body mass index, or disease duration. These results show that EDS can have an immense negative impact on quality of life. The causes of EDS are multifactorial, which complicates its treatment. Further investigations are required to determine the safety and efficacy of potential EDS therapies and to develop novel EDS treatments in PD.

Abstract TP159: Natural History of Carotid Intima-Media Thickness and Plaque in Real World Clinical Practice; A Single Center Experience

Background: Evaluation of carotid and vertebral artery with duplex sonography (DUS) is useful method for estimating systemic atherosclerotic risk. Regarding asymptomatic carotid plaque, how they change over time and how they should be properly managed are not well investigated yet. We investigated the natural history of carotid and vertebral arteries plaque or intima-media thickness (IMT) with best medical therapy in real clinical practice.

Methods: We consecutively enrolled patients who undergone DUS more than twice. Severe symptomatic stenosis or cardioembolic steno-occlusion was excluded. The management was performed by physician’s discretion. Demographics and clinical variables were obtained. ‘Increased IMT’ was defined when average IMT was over 1mm. Plaque was defined as a focal structure encroaching into the arterial lumen at least 0.5mm or 50% of the surrounding IMT. Progress or regress of IMT was defined as more than 0.1mm change from the initial scan. Plaque progress was determined by semi-quantitative measurement (more than 0.1 mm change or supported by velocity change particularly when echolucent plaque) and visual exam. Increased IMT, plaque presence were interpreted at initial and follow-up scan. Factors related to progression or regression was analyzed.

Results: Total 155 patients (64.5% men, mean age 64.9±10.2) were enrolled. There were 111 (71.6%) stroke or transient ischemic attack, and others, non-stroke such as dizziness, headache, and for medical check-up. The interval between initial and second DUS was 23.5±12.0 months. In 132 (85.2%) patients, increased IMT or presence of atherosclerotic plaque was observed on initial scan. On follow-up scan, progress of IMT or plaque was observed in 60 (38.7%). Regress was also observed in 8 (5.2%) patients. Subjects with progress were older than those without (66.9±9.5 vs 63.7±10.5, p=0.053). Sex, risk factors, time interval and use of statin were not associated with the progress. The dyslipidemia were significantly associated with the regress of IMT or plaque (p=0.064).

Conclusion: During two years of follow-up, progression of IMT or plaque was observed in 38.7% and regression in 5.2%. Older subjects are likely to progress and regression was more common in patient with dyslipidemia.

Association of arterial stiffness with cognition in patients with Lewy body disorder

The brachial-ankle pulse wave velocity (baPWV) is a marker for arterial stiffness, which is associated with cardiovascular diseases. Arterial stiffness is associated with cognitive function in the elderly and patients with Alzheimer's disease (AD). We aimed to investigate the association between arterial stiffness and cognitive function in patients with Lewy body disorder (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). We consecutively included 123 patients with PD, 10 patients with DLB, and 27 AD controls. Patients with PD were divided into three groups of normal cognition (PD-NC, n = 63), mild cognitive impairment (PD-MCI, n = 43), and dementia (PD-D, n = 17). Arterial stiffness, measured as baPWV, was compared between the PD-NC, PD-MCI, PD-D, DLB, and AD patients. In LBD, we analyzed the association between arterial stiffness and each cognitive domain with adjustment for covariates. Higher baPWV was significantly associated with cognitive decline in patients with LBD (baPWV in PD-D > PD-MCI > PD-NC; DLB > PD-NC). There was no significant difference in baPWV between PD-D, DLB, and AD patients. In LBD patients, higher baPWV was associated with lower mini mental state examination score (β ± SE = -0.003 ± 0.001, p = 0.007) and more severe dementia. Higher baPWV was also associated with lower performance in attention, language, visuospatial function, memory, and executive function in LBD patients. This suggests that vascular brain injury is associated with cognitive dysfunction in LBD.

Ambipolar transport and magneto-resistance crossover in a Mott insulator, Sr2IrO4

Electric field effect (EFE) controlled magnetoelectric transport in thin films of undoped and La-doped Sr₂IrO₄ (SIO) is investigated using ionic liquid gating. The temperature dependent resistance measurements exhibit insulating behavior in chemically and EFE doped samples with the band filling up to 10%. The ambipolar transport across the Mott gap is demonstrated by EFE tuning of the channel resistance and chemical doping. We observe a crossover from high temperature negative to low temperature positive magnetoresistance around  ∼80-90 K, irrespective of the filling. This temperature and magnetic field dependent crossover is discussed in the light of conduction mechanisms of SIO, especially variable range hopping (VRH), and its relevance to the insulating ground state of SIO.

Arterial Stiffness and Cardiovascular Autonomic Dysfunction in Patients with Parkinson's Disease

BACKGROUND

Pulse wave velocity is a marker of arterial stiffness and a surrogate marker of vascular damage. Autonomic abnormalities associated with blood pressure are relatively commonly observed in patients with Parkinson's disease (PD).

OBJECTIVE

The purpose of this study was to compare arterial stiffness between patients with PD and controls and investigate the associations between cardiovascular autonomic dysfunction and pulse wave velocity in PD.

METHODS

One hundred twenty-five PD patients without diabetes mellitus were enrolled into this study, along with 22 age-matched controls. Orthostatic vital signs and ambulatory 24-hour blood pressure monitoring values were recorded. Pulse wave velocity was used to evaluate arterial stiffness.

RESULTS

In PD, greater arterial stiffness was associated with orthostatic hypotension, supine hypertension, nocturnal hypertension, and nondipping. Dopaminergic treatment did not influence cardiovascular autonomic dysfunction or arterial stiffness. Although pulse wave velocity was mildly increased in patients with PD compared to controls, the arterial stiffness in PD patients without autonomic failure was similar to that in normal controls. Stiffer arteries were found only in patients with PD and autonomic failure.

CONCLUSION

These findings suggest that cardiovascular autonomic dysfunction is associated with arterial stiffness in PD. PD itself does not affect arterial stiffness, whereas autonomic blood pressure disturbances influence alterations in arterial stiffness and architectural changes in the arteries of PD patients.

Utility of dysphagia grade in predicting endoscopic ultrasound T-stage of non-metastatic esophageal cancer

Patients with non-metastatic esophageal cancer routinely undergo endoscopic ultrasound (EUS) for loco-regional staging. Neoadjuvant therapy is recommended for ≥T3 tumors while upfront surgery can be considered for ≤T2 lesions. The aim of this study was to determine if the degree of dysphagia can predict the EUS T-stage of esophageal cancer. One hundred eleven consecutive patients with non-metastatic esophageal cancer were retrospectively reviewed from a database. Prior to EUS, patients' dysphagia grade was recorded. Correlation between dysphagia grade and EUS T-stage, especially in reference to predicting ≥T3 stage, was determined. The correlation of dysphagia grade with EUS T-stage (Kendall's tau coefficient) was 0.49 (P < 0.001) for the lower and 0.59 (P = 0.008) for the middle esophagus. The sensitivity and specificity of dysphagia grade ≥2 (can only swallow semi-solids/liquids) for T3 cancer were 56% (95% confidence interval [CI] 43-67%) and 93% (95% CI 79-98%), respectively. The sensitivity, specificity, and positive predictive value of dysphagia grade ≥3 (can only swallow liquids or total dysphagia) for T3 lesions were 36% (95% CI 25-48%), 100% (95% CI 89-100%), and 100% (95% CI 83-100%), respectively. Overall, there was a significant positive correlation between dysphagia grade and the EUS T-stage of esophageal cancer. All patients with dysphagia grade ≥3 had T3 lesions. This may have clinical implications for patients who can only swallow liquids or have complete dysphagia by allowing for prompt initiation of neoadjuvant therapy, especially in countries/centers where EUS service is difficult to access in a timely manner or not available.

Cardiovascular Autonomic Dysfunction in Mild and Advanced Parkinson's Disease

Objective

The purpose of the present study was to investigate cardiovascular autonomic dysfunction in patients with Parkinson’s disease (PD) with mild to severe stages of motor symptoms and to compare cardiovascular autonomic dysfunction between drug-naïve and dopaminergic drug-treated groups.

Methods

This study included 188 PD patients and 25 age-matched healthy controls who underwent head-up tilt-testing, 24-h ambulatory blood pressure (BP) monitoring and 24-h Holter monitoring. Autonomic function test results were evaluated among groups categorized by motor symptom severities (mild vs. moderate vs. severe) and treatment (drug-naïve or dopaminergic drug treatment).

Results

Orthostatic hypotension and supine hypertension were more frequent in patients with PD than in healthy controls. The frequencies of orthostatic hypotension, supine hypertension, nocturnal hypertension and non-dipping were not different among groups. Additionally, no significant differences were detected in supine BP, orthostatic BP change, nighttime BP, nocturnal BP dipping, or heart rate variabilities among groups.

Conclusions

Cardiovascular autonomic dysfunction is not confined to moderate to severe PD patients, and starts early in the course of the disease in a high proportion of PD patients. In addition, dopaminergic drug treatments do not affect cardiovascular autonomic function.

Association between urine protein/creatinine ratio and cognitive dysfunction in Lewy body disorders

BACKGROUND

Impaired renal function and proteinuria have been associated with cognitive impairment and dementia. Chronic kidney disease is considered to be an independent risk factor for Lewy body spectrum disorders (LBD). However, few studies have mentioned an association between proteinuria and cognition in LBD. We investigated the relationship between proteinuria and cognitive dysfunction in patients with Parkinson's disease (PD) and dementia with Lewy bodies (DLB).

METHODS

Among 186 patients with LBD, 53 had PD-normal cognition (PD-NC), 76 had PD-mild cognitive impairment (PD-MCI), 43 had PD-dementia (PDD) and 14 had DLB. The urine protein/creatinine ratio was calculated using the spot urine test and brain magnetic resonance scans was obtained in all patients.

RESULTS

The urine protein/creatinine ratio was significantly higher in patients with PDD and DLB than in those with PD-MCI, PD-NC patients and healthy controls, and was correlated with white matter hyperintensities on magnetic resonance imaging. All abnormal neuropsychological test results were associated with increased urine protein/creatinine ratio. After controlling for age, education, symptom duration, diabetes mellitus, hypertension, and parkinsonian motor severity, the urine protein/creatinine ratio was significantly associated with decreased cognition.

CONCLUSION

The urine protein/creatinine ratio was associated with cognitive status in LBD. These finding suggests that increased protein excretion is associated with cognitive dysfunction in patients with LBD.

Cardiovascular autonomic dysfunctions in elderly patients with essential tremor: comparison with healthy controls

Questionnaire-based analyses show that patients with essential tremor (ET) may have several autonomic dysfunctions, especially in the cardiovascular and genitourinary domains; yet the laboratory correlates of autonomic dysfunction in ET are unknown and have not been studied. Herein, we explored whether sympathetic and parasympathetic functions differed between control subjects and patients with ET. Seventy-five elderly patients with ET were enrolled in this study, along with 25 age-matched controls. Orthostatic vital signs, ambulatory 24-h blood pressure monitoring and 24-h Holter monitoring values were recorded and metaiodobenzylguanidine (MIBG) uptake was assessed using the heart-to-mediastinum ratio (H/M ratio). The frequencies of orthostatic hypotension, supine hypertension, nocturnal hypertension and non-dipping were not different between the ET patients and the controls, although ET patients had more episodes of orthostatic intolerance. The ET group also had similar heart rate variations as the control group for all the time-domains. The mean H/M ratios for the ET group were not statistically different from that of the control group. This result proves that the autonomic control of the cardiovascular system is normal in ET.

Autonomic Nervous System Dysfunction in Patients With Parkinson Disease Having Depression

BACKGROUND AND AIM

Both depression and cardiovascular autonomic dysfunctions, such as orthostatic hypotension, supine hypertension, and the absence of normal nocturnal blood pressure (BP) fall ("nondipping"), occur relatively commonly in Parkinson disease (PD); however, the relationship between depression and cardiovascular autonomic abnormalities has not been established. In this study, we sought to determine whether the cardiovascular autonomic abnormalities found in PD are associated with depression.

METHODS

Among 129 nondemented, levodopa-naive patients with mild PD, 44 had depression. Orthostatic vital signs and ambulatory 24-hour BP monitoring were recorded, and geriatric depressive scales were obtained in all patients. Associations between orthostatic hypotension, supine hypertension, nocturnal hypertension, nondipping, and depression were analyzed. The ratio of the standard deviation of 24-hour heart rate to that of systolic BP (SBP) was utilized as an index of baroreflex-cardiovagal function.

RESULTS

Depression was associated with orthostatic hypotension, and patients with depression had higher SBP change during orthostasis and attenuated cardiovagal dysfunction as observed during ambulatory BP monitoring. Across individuals, values for orthostatic changes in BP were correlated with values for geriatric depressive scale.

CONCLUSION

Depression is associated with neurocirculatory abnormalities-especially orthostatic hypotension-in early PD. Although the association does not imply causation, this result suggests that depression in PD might be associated with functional impairment of the autonomic nervous system and its pathologic substrate.

Successive Magnetic-Field-Induced Transitions and Colossal Magnetoelectric Effect in Ni_{3}TeO_{6}

We report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni_{3}TeO_{6} that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 μC/cm^{2}, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behind the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. The resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.

Effect of Rivastigmine on Behavioral and Psychiatric Symptoms of Parkinson's Disease Dementia

Objective

A recent study showed that rivastigmine and memantin improved behavioral and psychiatric symptoms of dementia (BPSD) in Alzheimer’s dementia. Furthermore, according to recent guidelines presented by the Movement Disorder Society, rivastigmine is efficacious for the treatment of dementia in Parkinson’s disease (PD). We investigated the efficacy of rivastigmine for BPSD in patients with Parkinson’s disease dementia (PDD).

Methods

Twenty-three patients in whom cognitive impairment occurred at least one year after a diagnosis of PD participated in this open-label trial. Cognitive, psychiatric, and motor symptoms were assessed before and after 24 weeks of treatment with rivastigmine using unstructured clinical assessments and rating scales including the Unified Parkinson’s Disease Rating Scale, Mini-Mental State Examination (MMSE), and the Neuropsychiatric Inventory.

Results

Age (± standard deviation) was 74.7 ± 5.9 years, average duration of PD was 3.5 ± 3.7 years, Hoehn and Yahr scores were 2.2 ± 0.8, and baseline MMSE scores were 19.1 ± 4.2. Improvements in global mental symptoms and neuropsychiatric symptoms were significant; among them, hallucination, depression and appetite changes improved. Caregiver distress significantly decreased, including distress resulting from hallucinations, depression, apathy, and appetite changes.

Conclusions

Although controlled trials are required, the findings suggest that rivastigmine is useful for control of several neuropsychiatric symptoms and beneficial for caregiver distress in patients with PDD.

Neuropsychiatric symptoms in Parkinson's disease dementia are associated with increased caregiver burden

Objective

Neuropsychiatric symptoms are common in Parkinson’s disease dementia (PDD). Frequent and severe neuropsychiatric symptoms create high levels of distress for patients and caregivers, decreasing their quality of life. The aim of this study was to investigate neuropsychiatric symptoms that may contribute to increased caregiver burden in PDD patients.

Methods

Forty-eight PDD patients were assessed using the 12-item Neuropsychiatric Inventory (NPI) to determine the frequency and severity of mental and behavioral problems. The Burden Interview and Caregiver Burden Inventory were used to evaluate caregiver burden.

Results

All but one patient showed one or more neuropsychiatric symptoms. The three most frequent neuropsychiatric symptoms were apathy (70.8%) and anxiety (70.8%), followed by depression (68.7%). More severe neuropsychiatric symptoms were significantly correlated with increased caregiver burden. The domains of delusion, hallucination, agitation and aggression, anxiety, irritability and lability, and aberrant motor behavior were associated with caregiver stress. After controlling for age and other potential confounding variables, total NPI score was significantly associated with caregiver burden.

Conclusions

The results of this study confirm that neuropsychiatric symptoms are frequent and severe in patients with PDD and are associated with increased caregiver distress. A detailed evaluation and management of neuropsychiatric symptoms in PDD patients appears necessary to improve patient quality of life and reduce caregiver burden.

Amelioration of high fat diet-induced glucose intolerance by blockade of Smad4 in pancreatic beta-cells

BACKGROUND

In this study, we investigated whether Smad4 signaling is involved in the regulation of beta-cell function using a high fat diet (HFD)-induced obesity mouse model.

METHODS

Beta-cell-specific Smad4-knockout mice (Smad4(-/-)RIP-Cre(+); β-Smad4KO) were generated by mating Smad4 (flox/flox) mice with rat insulin promoter (RIP)-Cre mice. Mice were fed a HFD beginning at 6 weeks of age for 16 weeks. Body weight, food intake, fasting and fed glucose levels, and glucose and insulin tolerance were measured.

RESULTS

The expression of Smad4 mRNA was significantly decreased in the islets of β-Smad4KO mice. In wild-type mice, Smad4 mRNA was significantly decreased at 18 weeks of age as compared with 8 weeks of age. On a regular chow diet, β-Smad4KO mice showed no differences in body weight, fed and fasting blood glucose levels, and glucose tolerance compared with wild-type mice. When fed a HFD, body weight gain was significantly reduced in β-Smad4KO mice as compared with wild-type mice, although the amount of food intake was not different. During the HFD, fed and fasting blood glucose levels, glucose stimulated insulin secretion, disposition index and glucose tolerance were significantly improved in β-Smad4KO mice as compared with wild-type mice. However, insulin tolerance tests showed no differences between the 2 groups.

CONCLUSION

Inhibition of Smad4 in beta-cells conferred mild but significant improvements in glucose levels and glucose tolerance in HFD-induced obese mice. Therefore, regulation of Smad4 expression may be one of the mechanisms regulating physiological expansion of beta-cells during development of type 2 diabetes.