Prevalence, incidence, and mortality of PD: a door-to-door survey in Ilan county, Taiwan

Phytomolecules from conventional to nano form: Next-generation approach for Parkinson's disease

The incidence of neurodegenerative diseases is increasing exponentially worldwide. Parkinson's disease (PD) is a neurodegenerative disease caused by factors like oxidative stress, gene mutation, mitochondrial dysfunction, neurotoxins, activation of microglial inflammatory mediators, deposition of Lewy's bodies, and α- synuclein proteins in the neurons leading to neuroinflammation and neurodegeneration in the substantia nigra. Hence the development of efficacious neuro-therapy is in demand which can prevent neurodegeneration and protect the nigrostriatal pathway. One of the approaches for managing PD is reducing oxidative stress due to aging and other co-morbid diseased conditions. The phytomolecules are reported as safe and efficacious antioxidants as they contain different secondary metabolites. However, the limitations of low solubility restricted permeability through the blood-brain barrier, and low bioavailability limits their clinical evaluation and application. This review discusses the therapeutic efficacy of phytomolecules in PD and different nanotechnological approaches to improve their brain permeability.

Neuroprotective Potential of Melatonin: Evaluating Therapeutic Efficacy in Alzheimer's and Parkinson's Diseases

Decreased melatonin levels have been linked to both Alzheimer's disease (AD) and Parkinson's disease (PD), which are the two most prevalent neurodegenerative disorders. The development of sleep disorders is widespread in patients diagnosed with AD or PD. In this regard, calcification of the pineal gland, typically seen in the third decade, has been associated with a reduction in melatonin production. Recent studies have suggested that exogenous melatonin application can be utilized to treat sleep disorders in patients with neurodegenerative diseases. Furthermore, research has shown that deficiencies in melatonin levels in patients with AD or PD begin before a diagnosis of either disease is made. These findings could encourage further research on melatonin as a potential biomarker for the diagnosis or a possible area for the early treatment of these diseases. Many clinical studies have also produced data denoting melatonin treatment as a method to reduce the detrimental neurocognitive effects of these diseases. Further research on the role of melatonin in neurodegenerative diseases could expand symptomatic and prophylactic treatment options for diseases such as AD and PD. This review investigates melatonin's physiological properties, its role in AD and PD, and current findings on its potential therapeutic benefits in AD and PD patients.

Optical coherence tomography angiography measurements in Parkinson's disease: A systematic review and meta-analysis

Optical coherence tomography angiography (OCT-A) is an ocular imaging technology that has emerged as a non-invasive tool to evaluate retinal microvascular changes in neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease. While several studies have reported on the presence of pathologic retinal microvascular alterations in PD, the utility of OCT-A as a biomarker for PD evaluation is still unclear. A systematic review and meta-analysis were performed to explore the current evidence for the role of OCT-A in PD published up until June 2022. PubMed, Scopus, and Web of Science databases were used to systematically identify relevant papers and a meta-analysis was conducted using Stata16 software according to the level of heterogeneity applying a random- or fixed-effect model. Thirteen studies of 925 eyes in the PD group and 1501 eyes in the control group assessing OCT-A findings in PD patients were included. The meta-analyses revealed that the foveal region of PD patients had a significantly lower vessel density in the superficial capillary plexus (SCP) compared to healthy controls but that there were no significant differences in the foveal avascular zone, the SCP in whole, parafoveal, and perifoveal regions, and deep capillary plexus. OCT-A metrics may act as a potential biomarker for a more accurate and early PD diagnosis. Still, the OCT-A algorithms and interchangeability between OCT-A devices require further standardization to draw clinical conclusions regarding their utility.

Liquid-liquid phase separation regulates alpha-synuclein aggregate and mitophagy in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world, and alpha-synuclein (α-syn) abnormal aggregate and mitochondrial dysfunction play a crucial role in its pathological development. Recent studies have revealed that proteins can form condensates through liquid-liquid phase separation (LLPS), and LLPS has been found to be widely present in α-syn aberrant aggregate and mitophagy-related protein physiological processes. This review summarizes the occurrence of α-syn LLPS and its influencing factors, introduces the production and transformation of the related protein LLPS during PINK1-Parkin-mediated mitophagy, hoping to provide new ideas and methods for the study of PD pathology.

Parkinson's Disease: A Narrative Review on Potential Molecular Mechanisms of Sleep Disturbances, REM Behavior Disorder, and Melatonin

Parkinson's disease (PD) is one of the most common neurodegenerative diseases. There is a wide range of sleep disturbances in patients with PD, such as insomnia and rapid eye movement (REM) sleep behavior disorder (or REM behavior disorder (RBD)). RBD is a sleep disorder in which a patient acts out his/her dreams and includes abnormal behaviors during the REM phase of sleep. On the other hand, melatonin is the principal hormone that is secreted by the pineal gland and significantly modulates the circadian clock and mood state. Furthermore, melatonin has a wide range of regulatory effects and is a safe treatment for sleep disturbances such as RBD in PD. However, the molecular mechanisms of melatonin involved in the treatment or control of RBD are unknown. In this study, we reviewed the pathophysiology of PD and sleep disturbances, including RBD. We also discussed the potential molecular mechanisms of melatonin involved in its therapeutic effect. It was concluded that disruption of crucial neurotransmitter systems that mediate sleep, including norepinephrine, serotonin, dopamine, and GABA, and important neurotransmitter systems that mediate the REM phase, including acetylcholine, serotonin, and norepinephrine, are significantly involved in the induction of sleep disturbances, including RBD in PD. It was also concluded that accumulation of α-synuclein in sleep-related brain regions can disrupt sleep processes and the circadian rhythm. We suggested that new treatment strategies for sleep disturbances in PD may focus on the modulation of α-synuclein aggregation or expression.

Voiding Dysfunction Due to Urethral Sphincter Dysfunction Might Be an Early Neurological Presentation of Central Nervous System Disorders in Aged Patients

PURPOSE

To investigate the incidence of central nervous system (CNS) diseases in adult patients with voiding dysfunction and videourodynamics (VUDS) proven urethral sphincter dysfunction.

METHODS

This retrospective analysis reviewed the medical charts of patients aged > 60 years who underwent VUDS for non-prostatic voiding dysfunction from 2006 to 2021. A chart review was performed to search for the occurrence and treatment of CNS diseases after the VUDS examination up to 2022. The diagnosis of CNS disease, such as cerebrovascular accidents (CVA), Parkinson's disease (PD), and dementia, by neurologists was also retrieved from the charts. Based on the VUDS findings, patients were divided into the following subgroups: dysfunctional voiding (DV), poor relaxation of the external sphincter (PRES), and hypersensitive bladder (HSB) and coordinated sphincter subgroups. The incidence of CVA, PD, and dementia in each subgroup was recorded and compared among them using one-way analysis of variance (ANOVA).

RESULTS

A total of 306 patients were included. VUDS examinations revealed DV in 87 patients, PRES in 108, and HSB in 111. Among them, 36 (11.8%) patients had CNS disease, including CVA in 23 (7.5%), PD in 4 (1.3%), and dementia in 9 (2.9%). Among the three subgroups, the DV group had the highest incidence rate of CNS disease (n = 16, 18.4%), followed by PRES (n = 12, 11.1%) and HSB (n = 8, 7.2%). However, no significant difference was noted in the incidence of CNS disease across the three subgroups. Nevertheless, the incidence of CNS disease was higher in patients with DV and PRES than that in the general population.

CONCLUSIONS

The incidence of CNS diseases was high in patients aged > 60 years with voiding dysfunction due to urethral sphincter dysfunction. Patients with VUDS-confirmed DV had the highest incidence of CNS disease among the three subgroups.

The impact of active community-based survey on dementia detection ratio in Taiwan: A cohort study with historical control

Background

Although early dementia detection is crucial to optimize the treatment outcomes and the management of associated symptoms, the published literature is scarce regarding the effectiveness of active screening protocols in enhancing dementia awareness and increasing the rate of early detection. The present study compared the detection ratio of an active community-based survey for dementia detection with the detection ratio of passive screening during routine clinical practice. Data for passive screening were obtained from the National Health Insurance (NHI) system, which was prospectively collected during the period from 2000 to 2003.

Design

A population-based cohort study with historical control.

Setting

Taiwan.

Participants

A total of 183 participants aged 65 years or older were involved in a community-based survey. Data from 1,921,308 subjects aged 65 years or older were retrieved from the NHI system.

Measurements

An adjusted detection ratio, defined as a ratio of dementia prevalence to incidence was used.

Results

The results showed that the dementia prevalence during the 2000-2003 period was 2.91% in the elderly population, compared with a prevalence of 6.59% when the active survey was conducted. The incidence of dementia in the active survey cohort was 1.83%. Overall, the dementia detection ratio was higher using active surveys [4.23, 95% confidence interval (CI): 2.68-6.69] than using passive detection (1.45, 95% CI: 1.43-1.47) for those aged 65-79 years. Similar findings were observed for those aged 80 years and older.

Conclusion

The implementation of an active community-based survey led to a 3-fold increase in the detection rate of early dementia detection compared to passive screening during routine practice.

Trends in health service use among persons with Parkinson's disease by rurality: A population-based repeated cross-sectional study

BACKGROUND

The global burden of Parkinson's disease (PD) has more than doubled over the past three decades, and this trend is expected to continue. Despite generally poorer access to health care services in rural areas, little previous work has examined health system use in persons with PD by rurality. We examined trends in the prevalence of PD and health service use among persons with PD by rurality in Ontario, Canada.

METHODS

We conducted a repeated, cross-sectional analysis of persons with prevalent PD aged 40+ years on April 1st of each year from 2000 to 2018 using health administrative databases and calculated the age-sex standardized prevalence of PD. Prevalence of PD was also stratified by rurality and sex. Negative binomial models were used to calculate rate ratios with 95% confidence intervals comparing rates of health service use in rural compared to urban residents in 2018.

RESULTS

The age-sex standardized prevalence of PD in Ontario increased by 0.34% per year (p<0.0001) and was 459 per 100,000 in 2018 (n = 33,479), with a lower prevalence in rural compared to urban residents (401 vs. 467 per 100,000). Rates of hospitalizations and family physician visits declined over time in both men and women with PD in rural and urban areas, while rates of emergency department, neurologist, and other specialist visits increased. Adjusted rates of hospitalizations were similar between rural and urban residents (RR = 1.04, 95% CI [0.96, 1.12]), while rates of emergency department visits were higher among rural residents (RR = 1.35, 95% CI [1.27, 1.42]). Rural residents had lower rates of family physician (adjusted RR = 0.82, (95% CI [0.79, 0.84]) and neurologist visits (RR = 0.74, 95% CI [0.72, 0.77]).

INTERPRETATION

Lower rates of outpatient health service use among persons residing in rural regions, contrasting with higher rates of emergency department visits suggest inequities in access. Efforts to improve access to primary and specialist care for persons with PD in rural regions are needed.

Prospects for the Development of Pink1 and Parkin Activators for the Treatment of Parkinson's Disease

Impaired mitophagy is one of the hallmarks of the pathogenesis of Parkinson's disease, which highlights the importance of the proper functioning of mitochondria, as well as the processes of mitochondrial dynamics for the functioning of dopaminergic neurons. At the same time, the main factors leading to disruption of mitophagy in Parkinson's disease are mutations in the Pink1 and Parkin enzymes. Based on the characterized mutant forms, the marked cellular localization, and the level of expression in neurons, these proteins can be considered promising targets for the development of drugs for Parkinson's therapy. This review will consider such class of drug compounds as mitophagy activators and these drugs in the treatment of Parkinson's disease.

Zonisamide's Efficacy and Safety on Parkinson's Disease and Dementia with Lewy Bodies: A Meta-Analysis and Systematic Review

Objective

Clinical data has recently shown an association between Parkinson's disease (PD), Dementia with Lewy bodies (DLB), and zonisamide. The purpose of this study was to thoroughly evaluate the efficacy and safety of zonisamide in PD and DLB.

Methods

Pubmed, the Cochrane Library, Web of Science, and Embase databases were searched for all randomized clinical trials (RCTS) on the role of zonisamide in PD and DLB that were completed by April 18, 2022. UPDRS II (off) total score, UPDRS III total score, Daily "off" time, and UPDRS Part IV, Nos. 32, 33, and 34 were used as clinical efficacy endpoints. Adverse events reported in the RCTs will be considered in the final safety analysis. To better understand the effect of zonisamide on the efficacy and safety of PD and DLB, the UPDRS III total score and the six overlapping adverse events were examined in subgroups. Either a fixed effects model analysis (OR) or a random effects model analysis (MD) is used to figure out the mean difference (MD) and the relative risk.

Results

Seven articles involving 1749 patients (916 PD and 833 DLB) were included in this study. Compared to the control group, zonisamide could significantly reduce the UPDRS III total score in patients with PD and DLB (WMD-2.27 [95% CI: -3.06, -1.48], p < 0.0001). For patients with PD, compared to the control group, zonisamide could significantly reduce the UPDRS II (off) total score (WMD-0.81 [95% CI: -1.36, -0.26], p = 0.004), daily "off" time (WMD-0.67 [95% CI: -1.10, 0.24], p = 0.002), and UPDRS part IV, No. 32 worsen (OR-3.48 [95% CI: 1.20, 10.10], p = 0.02). In terms of safety, compared with the control group, for patients with DLB, zonisamide could significantly increase the incidence of contusion (OR-0.60 [95% CI: 0.38, 0.96], p = 0.03) and may increase the probability of reduced appetite (OR-3.13 [95% CI: 1.61, 6.08], p = 0.0008). And for patients with PD, zonisamide may increase the probability of somnolence (OR-2.17 [95% CI: 1.25, 3.76], p = 0.006).

Conclusions

For the analysis of the current study results, our results show that zonisamide could improve the motor function in patients with PD and DLB and improve the activities of daily living (off) and wearing off and decrease the duration of dyskinesia in patients with PD. In terms of safety, the use of zonisamide significantly increases the probability of contusion in patients with DLB and may increase the probability of reduced appetite in patients with DLB and somnolence in patients with PD. Zonisamide appears to be a new treatment option for patients with PD and DLB. However, the effectiveness and safety of zonisamide in the treatment of PD and DLB need to be further investigated.

Cost-effectiveness of the add-on exenatide to conventional treatment in patients with Parkinson’s disease when considering the coexisting effects of diabetes mellitus

Objective

This study aims to investigate the cost-effectiveness of the add-on exenatide to conventional pharmacotherapy in patients with Parkinson’s disease (PD) when considering the coexistence of diabetes mellitus (DM).

Methods

We used the Keelung and Community-based Integrated Screening databases to understand the medical utilisation in the Hoehn and Yahr stages of patients with PD. A Markov model with 1-year cycle length and 50-year time horizon was used to assess the cost-effectiveness of add-on exenatide to conventional pharmacotherapy compared to conventional pharmacotherapy alone. All costs were adjusted to the value of the new Taiwanese dollar (NT$) as of the year 2020. One-way sensitivity and probability analyses were performed to test the robustness of the results.

Results

From a societal perspective, the add-on exenatide brought an average of 0.39 quality-adjusted life years (QALYs) gained, and a cost increment of NT$104,744 per person in a 50-year horizon compared to conventional pharmacotherapy. The incremental cost-effectiveness ratio (ICER) was NT$268,333 per QALY gained. As the ICER was less than the gross domestic product per capita (NT$839,558), the add-on exenatide was considered to be very cost-effective in the two models, according to the World Health Organization recommendation. Add-on exenatide had a 96.9% probability of being cost-effective in patients with PD, and a 100% probability of being cost-effective in patients with PD and DM.

Conclusion

Add-on exenatide is cost-effective in PD combined with DM. Considering that DM may be a risk factor for neurodegenerative diseases, exenatide provides both clinical benefits and cost-effectiveness when considering both PD and DM.

Noninvasive neuromodulation in Parkinson's disease: Neuroplasticity implication and therapeutic perspectives

Noninvasive brain stimulation techniques can be used to study in vivo the changes of cortical activity and plasticity in subjects with Parkinson's disease (PD). Also, an increasing number of studies have suggested a potential therapeutic effect of these techniques. High-frequency repetitive transcranial magnetic stimulation (rTMS) and anodal transcranial direct current stimulation (tDCS) represent the most used stimulation paradigms to treat motor and nonmotor symptoms of PD. Both techniques can enhance cortical activity, compensating for its reduction related to subcortical dysfunction in PD. However, the use of suboptimal stimulation parameters can lead to therapeutic failure. Clinical studies are warranted to clarify in PD the additional effects of these stimulation techniques on pharmacologic and neurorehabilitation treatments.

Imaging the neural underpinnings of freezing of gait in Parkinson’s disease

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Review of recent (after 2012) imaging studies on Parkinsonian freezing of gait.

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Virtual reality studies report functional decoupling of cortico-striatal circuits.

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Motor imagery studies reveal increased recruitment of parieto-occipital regions.

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fNIRS studies converge on reporting higher activity within prefrontal regions.

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Imaging findings support pathophysiological models of freezing of gait.

Freezing of gait (FoG) is a paroxysmal and sporadic gait impairment that severely affects PD patients’ quality of life. This review summarizes current neuroimaging investigations that characterize the neural underpinnings of FoG in PD. The review presents and discusses the latest advances across multiple methodological domains that shed light on structural correlates, connectivity changes, and activation patterns associated with the different pathophysiological models of FoG in PD. Resting-state fMRI studies mainly report cortico-striatal decoupling and disruptions in connectivity along the dorsal stream of visuomotor processing, thus supporting the ‘interference’ and the ‘perceptual dysfunction’ models of FoG. Task-based MRI studies employing virtual reality and motor imagery paradigms reveal a disruption in functional connectivity between cortical and subcortical regions and an increased recruitment of parieto-occipital regions, thus corroborating the ‘interference’ and ‘perceptual dysfunction’ models of FoG. The main findings of fNIRS studies of actual gait primarily reveal increased recruitment of frontal areas during gait, supporting the ‘executive dysfunction’ model of FoG. Finally, we discuss how identifying the neural substrates of FoG may open new avenues to develop efficient treatment strategies.

The Association Between Parkinson's Disease and Attention-Deficit Hyperactivity Disorder

While Parkinson’s disease (PD) and attention-deficit hyperactivity disorder (ADHD) are two distinct conditions, it has been hypothesized that they share several overlapping anatomical and neurochemical changes. In order to investigate that hypothesis, this study used claims data from Taiwan’s Longitudinal Health Insurance Database 2000 to provide the significant nationwide population-based evidence of an increased risk of PD among ADHD patients, and the connection between the two conditions was not the result of other comorbidities. Moreover, this study showed that the patients with PD were 2.8 times more likely to have a prior ADHD diagnosis compared with those without a prior history of ADHD. Furthermore, an animal model of ADHD was generated by neonatally injecting rats with 6-hydroxydopamine (6-OHDA). These rats were subjected to behavior tests and the 99mTc-TRODAT-1 brain imaging at the juvenile stage. Compared to control group rats, the 6-OHDA rats showed a significantly reduced specific uptake ratio in the striatum, indicating an underlying PD-linked pathology in the brains of these ADHD phenotype-expressing rats. Overall, these results support that ADHD shares a number of anatomical and neurochemical changes with PD. As such, improved knowledge of the neurochemical mechanisms underlying ADHD could result in improved treatments for various debilitating neurological disorders, including PD.

Changes in Epidemiological Trends and Rehabilitation Usage in Neurological Diseases in Korea: Parkinson's Disease

Parkinson's disease (PD) is a neurodegenerative disorder characterized by typical motor symptoms such as resting tremor, bradykinesia, and rigidity, as well as non-motor manifestations, including psychiatric symptoms, autonomic dysfunction, and cognitive impairment. These symptoms induce a marked impact on functional independence in daily activities and quality of life in PD patients. Recent guidelines recommend adequate rehabilitation education and treatment from the early stages of PD, and rehabilitation has become part of standard care for PD. In Korea, the number of patients with PD has more than tripled over 15 years, from 39,265 in 2004 to 125,607 in 2019. However, the rehabilitation usage of PD patients has not changed remarkably, and it remains suboptimal in Korea compared to several developed countries, which have advanced and disseminated guidelines and implemented specialized care delivery systems for PD over the past 20 years. Additional efforts are warranted to provide adequate rehabilitation therapies for PD patients in Korea.

Recalling the pathology of Parkinson's disease; lacking exact figure of prevalence and genetic evidence in Asia with an alarming outcome: A time to step-up

Parkinson's disease (PD) is the second most common and progressive neurodegenerative disease globally, with major symptoms like bradykinesia, impaired posture, and tremor. Several genetic and environmental factors have been identified but elucidating the main factors have been challenging due to the disease's complex nature. Diagnosis, prognosis, and management of such diseases are challenging and require effective targeted attention in developing countries. Recently, PD is growing rapidly in many crowded Asian countries as an alarming threat with inadequate knowledge of its prevalence, genetic architecture, and geographic distribution. This study gave an in-depth overview of the prevalence, incidence and genomic/genetics studies published so far in the Asian population. To the best of our knowledge, PD has increased significantly in several Asian countries, including China, South Korea, Japan, Thailand, and Israel over the past few years, requiring a greater level of care and attention. Genetic screening of families with PD at national levels and establishing an official database of PD cases are essential to get a comprehensive and conclusive view of the exact prevalence and genetic diversity of PD in the Asian population to properly manage and treat the disease.

Imbalance of Lysine Acetylation Contributes to the Pathogenesis of Parkinson's Disease

Parkinson’s disease (PD) is one of the most common neurodegenerative disorders. The neuropathological features of PD are selective and progressive loss of dopaminergic neurons in the substantia nigra pars compacta, deficiencies in striatal dopamine levels, and the presence of intracellular Lewy bodies. Interactions among aging and genetic and environmental factors are considered to underlie the common etiology of PD, which involves multiple changes in cellular processes. Recent studies suggest that changes in lysine acetylation and deacetylation of many proteins, including histones and nonhistone proteins, might be tightly associated with PD pathogenesis. Here, we summarize the changes in lysine acetylation of both histones and nonhistone proteins, as well as the related lysine acetyltransferases (KATs) and lysine deacetylases (KDACs), in PD patients and various PD models. We discuss the potential roles and underlying mechanisms of these changes in PD and highlight that restoring the balance of lysine acetylation/deacetylation of histones and nonhistone proteins is critical for PD treatment. Finally, we discuss the advantages and disadvantages of different KAT/KDAC inhibitors or activators in the treatment of PD models and emphasize that SIRT1 and SIRT3 activators and SIRT2 inhibitors are the most promising effective therapeutics for PD.

Cost-Effectiveness Analysis of Deep Brain Stimulation for Parkinson Disease in Taiwan

BACKGROUND

Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an effective therapy for Parkinson disease (PD). However, cost-effectiveness analysis is required because most patients are older adults and decision makers must therefore consider whether the long-term effectiveness outweighs the initial cost.

METHODS

A Markov decision model was constructed on the basis of a societal perspective. The Hoehn and Yahr scale and Unified PD Rating Scale motor score were used in the polytomous logistic regression model. Markov Chain Monte Carlo simulation was used to initiate the probabilistic cost-effectiveness analysis.

RESULTS

The life-year gained (LYG) in the STN-DBS group and medication group was, respectively, 2.937 and 2.632 years at the 3-year follow-up and 7.417 and 5.971 years at the 10-year follow-up. The quality-adjusted life-year (QALY) gained in the STN-DBS and medication groups was, respectively, 1.739 and 1.220 at the 3-year follow-up and 4.189 and 2.88 at the 10-year follow-up. The incremental cost-effectiveness ratio of STN-DBS compared with medication was $147,065 per LYG and $123,436 per QALY gained at the 3-year follow-up and $36,833 and $69,033 at the 10-year follow-up, respectively. STN-DBS is an optimal strategy when the willingness to pay is $150,000 per LYG and over $90,000 per QALY gained in 3 years and when the willingness to pay is over $38,000 per LYG and over $41,000 per QALY gained in 10 years.

CONCLUSIONS

This study provided data comparing STN-DBS and medical treatment for PD with respect to LYG and QALY gained. STN-DBS was more cost-effective in terms of LYG and QALY gained according to the current gross domestic product of Taiwan.

Long-Term Voluntary Physical Exercise Exerts Neuroprotective Effects and Motor Disturbance Alleviation in a Rat Model of Parkinson's Disease

Background

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder affecting 7–10 million individuals. The pathologic hallmark of PD is nigrostriatal dopaminergic neuron loss, leading to several motor and nonmotor disturbances, such as akinesia, gait disturbance, depression, and anxiety. Recent animal studies have demonstrated that physical exercise improves behavioral and neuropathological deficits in PD. However, the exact underlying mechanism underlying this effect remains unclear. In this study, we investigated whether long-term exercise has neuroprotective effects on dopaminergic nigrostriatal neurons and whether it further alleviates impairment of the gait pattern, locomotor activity, akinesia, and anxiety-like behavior in PD rats.

Methods

A hemiparkinsonian rat model, generated by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle, was applied to evaluate neuroprotective effects and motor behaviors. Comprehensive spatiotemporal gait analysis, open-field locomotor activity, akinesia, apomorphine-induced rotational analysis, and dopaminergic neuron degeneration level were assessed every week and up to 8 weeks after daily voluntary running wheel exercise.

Results

Compared with the sham-treated group, we found that 10 weeks of voluntary exercise (i.e., 2-week exercise before PD lesion and 8-week exercise post-PD lesion) significantly reduced 6-OHDA-induced motor deficits in the gait pattern, akinesia, and rotational behavior in the exercise group. Immunohistochemically, a tyrosine hydroxylase-positive neuron in the substantia nigra was significantly preserved in the exercise group.

Conclusions

Our results demonstrated that long-term exercise training is effective for neuroprotection and further attenuates motor declines induced by 6-OHDA in an experimental model of PD. Our data further highlighted potential therapeutic effects of long-term physical exercise relevant to clinical effects for further potential application on human PD subjects.

Parkinson's disease in China: a forty-year growing track of bedside work

The number and health burden of Parkinson's disease increase rapidly in China. It is estimated that China will have nearly half of the Parkinson's disease population in the world in 2030. In this review, we present an overview of epidemiology and health economics status of Parkinson's disease across China and discuss the risk factors of Parkinson's disease and related complications. From the view of clinical research, we also discuss the current status of clinical trials, diagnostic biomarkers, treatment of Parkinson's disease, tertiary network and post-occupation education in Chinese Parkinson's disease clinics.

Parkinson's Disease in Intensive Care Unit: An Observational Study of Frequencies, Causes, and Outcomes

Objective:

To analyze the frequency, causes, and outcomes of admission to the Intensive Care Unit (ICU) among Parkinson's disease (PD) population so that preventive measures can be developed.

Methods:

We prospectively observed patients with diagnosis of PD admitted to ICU from January 2014 to December 2016. Based on etiology for hospital admission, they were divided into two groups – related to PD (further divided into direct or indirect) or not associated with PD at all. Etiology for hospitalization was determined from history and investigational data. The primary outcome was death or discharge from the hospital. Factors contributing to ICU admission were analyzed by comparing these patients with a cohort of 50 PD patients admitted to the neurology ward during the same study period. All values were expressed as mean (standard deviation) and percentages using SPSS version 16.0.

Results:

Fifty-three (36%) out of a total of 146 patients required ICU admission. Most common causes leading to admission in decreasing order of frequency were fever (34%), delirium (16%), falls (12%), encephalopathy (8%), gastrointestinal emergencies (6%); while direct disease-related severe dyskinesias were seen only in two patients (4%). 13.7% needed mechanical ventilation and mean duration of ventilation was 5.94 days with mortality rate of 20%. Significant factors predicting ICU admission, and thus, poor outcomes were age >65 years, history of previous admission within the last 12 months, delirium, and hypoalbuminemia. There was no significant association between the incidence of ICU admission and duration of disease or severity of the disease.

Conclusions:

Poor outcome in PD patients is due to systemic causes, hence multidisciplinary teamwork may improve outcome in these patients.

Region-Based Analysis of Prevalence and Incidence of Parkinson's Disease: Analysis of the National Sample Cohort in South Korea

Background and Purpose

The rapid increases in the elderly population and urbanization in South Korea have influenced both demographics and the environment. This study investigated trends in the prevalence and incidence of Parkinson's disease (PD), and the associations of PD with the urban and rural environments in South Korea.

Methods

This study examined subjects aged 40 years or older in a cohort constructed using the National Sample Cohort data set in South Korea during 2002–2013. We estimated the age-standardized prevalence and incidence of PD based on the 2002 population, and estimated their trends. We analyzed regional differences in these rates by dividing South Korea into three regions based on geographic characteristics and two regions based on the degree of urbanization.

Results

The standardized prevalence rates of PD per 100,000 increased significantly from 75.8 in 2003 to 136.8 in 2012 (p<0.0001), especially in older subjects. The standardized prevalence of PD was highest in metropolitan Seoul. The standardized incidence of PD per 100,000 was 13.9 in 2003 and 10.3 in 2012, with no significant trend (p>0.05). The standardized incidence of PD in younger subjects was lower in eastern Korea than in the other two regions, while in the older subjects it was lower in western Korea than in metropolitan Seoul over almost the entire analyzed period. The standardized incidence of PD did not differ significantly between metropolitan and nonmetropolitan areas.

Conclusions

The standardized prevalence of PD increased steadily from 2003 to 2012 in South Korea, while its standardized incidence has remained constant. There were regional differences in the prevalence and incidence of PD based on the degree of urbanization and the area of agricultural land.

Amantadine and the Risk of Dyskinesia in Patients with Early Parkinson's Disease: An Open-Label, Pragmatic Trial

Objective

We examined whether amantadine can prevent the development of dyskinesia.

Methods

Patients with drug-naïve Parkinson’s disease (PD), younger than 70 years of age and in the early stage of PD (Hoehn and Yahr scale < 3), were recruited from April 2011 to December 2014. The exclusion criteria included the previous use of antiparkinsonian medication, the presence of dyskinesia, significant psychological disorders, and previous history of a hypersensitivity reaction. Patients were consecutively assigned to one of 3 treatment groups in an open label fashion: Group A-1, amantadine first and then levodopa when needed; Group A-2, amantadine first, dopamine agonist when needed, and then levodopa; and Group B, dopamine agonist first and then levodopa when needed. The primary endpoint was the development of dyskinesia, which was analyzed by the Kaplan-Meier survival rate.

Results

A total of 80 patients were enrolled: Group A-1 (n = 27), Group A-2 (n = 27), and Group B (n = 26). Twenty-four patients were excluded from the analysis due to the following: withdrawal of amantadine or dopamine agonist (n = 9), alternative diagnosis (n = 2), withdrawal of consent (n = 1), and breach in the protocol (n = 12). After exclusion, 5 of the 56 (8.93%) patients developed dyskinesia. Patients in Group A-1 and A-2 tended to develop dyskinesia less often than those in Group B (cumulative survival rates of 0.933, 0.929, and 0.700 for A-1, A-2, and B, respectively; p = 0.453).

Conclusion

Amantadine as an initial treatment may decrease the incidence of dyskinesia in patients with drug-naïve PD.

Epidemiology of Parkinson's Disease-East Versus West

Background

The cause of PD at present remains unknown. A number of epidemiological studies have been conducted across the globe to ascertain the disease burden and the possible risk factors. In this review, we analyze the various studies from East and West with an aim to observe the important similarities and differences in the disease occurrence and risk factor profile.

Methods

A comprehensive search of descriptive and analytical epidemiological studies was undertaken. The descriptive studies and meta-analysis providing the standardised population rates were selected. The demographics, ethnicity and geographical differences between East and West were analysed. In analytical epidemiology, more established and well-studied non-genetic risk factors for PD were reviewed utilising the prospective cohort studies, case control studies and meta-analysis where available.

Results and Conclusion

PD is more common with increasing age and shows male predominance, which is more obvious in Western studies. The PD prevalence and incidence rates are slightly lower in the East compared to the West. Incidence studies on different ethnic populations in the same country have also found a lower occurrence of PD amongst Easterners compared to Westerners. Setting methodological differences aside, studies from East and West suggest a role for both environmental and genetic risk factors in PD causation. Smoking, caffeine intake and pesticide exposure are well-established risk factors across regions. There is a robust data for dairy product consumption, urate levels and physical activity in the West while studies on certain risk factors like head injury and alcohol show conflicting and mixed results.

Tamoxifen and the Risk of Parkinson's Disease in Female Patients with Breast Cancer in Asian People: A Nationwide Population-Based Study

Purpose

Whether tamoxifen affects the risk of neurodegenerative disease is controversial. This nationwide population-based study investigated the risk of Parkinson's disease (PD) associated with tamoxifen treatment in female patients with breast cancer using Taiwan's National Health Insurance Research Database.

Methods

A total of 5,185 and 5,592 female patients with breast cancer who did and did not, respectively, receive tamoxifen treatment between 2000 and 2009 were included in the study. Patients who subsequently developed PD were identified. A Cox proportional hazards model was used to compare the risk of PD between the aforementioned groups.

Results

Tamoxifen did not significantly increase the crude rate of developing PD in female patients with breast cancer (tamoxifen group, 16/5,169; non-tamoxifen group, 11/5,581; p=0.246). Tamoxifen did not significantly increase the adjusted hazard ratio (aHR) for subsequently developing PD (aHR, 1.310; 95% confidence interval [CI], 0.605-2.837; p=0.494). However, tamoxifen significantly increased the risk of PD among patients followed up for more than 6 years (aHR, 2.435; 95% CI, 1.008-5.882; p=0.048).

Conclusion

Tamoxifen treatment may increase the risk of PD in Taiwanese female patients with breast cancer more than 6 years after the initiation of treatment.

Survival and Causes of Death Among People With Clinically Diagnosed Synucleinopathies With Parkinsonism: A Population-Based Study

Importance

To our knowledge, a comprehensive study of the survival and causes of death of persons with synucleinopathies compared with the general population has not been conducted. Understanding the long-term outcomes of these conditions may inform patients and caregivers of the expected disease duration and may help with care planning.

Objective

To compare survival rates and causes of death among patients with incident, clinically diagnosed synucleinopathies and age- and sex-matched referent participants.

Design, Setting, and Participants

This population-based study used the Rochester Epidemiology Project medical records-linkage system to identify all residents in Olmsted County, Minnesota, who received a diagnostic code of parkinsonism from 1991 through 2010. A movement-disorders specialist reviewed the medical records of each individual to confirm the presence of parkinsonism and determine the type of synucleinopathy. For each confirmed patient, an age- and sex-matched Olmsted County resident without parkinsonism was also identified.

Main Outcomes and Measures

We determined the age- and sex-adjusted risk of death for each type of synucleinopathy, the median time from diagnosis to death, and the causes of death.

Results

Of the 461 patients with synucleinopathies, 279 (60.5%) were men, and of the 452 referent participants, 272 (60.2%) were men. From 1991 through 2010, 461 individuals received a diagnosis of a synucleinopathy (309 [67%] of Parkinson disease, 81 [17.6%] of dementia with Lewy bodies, 55 [11.9%] of Parkinson disease dementia, and 16 [3.5%] of multiple system atrophy with parkinsonism). During follow-up, 68.6% (n = 316) of the patients with synucleinopathies and 48.7% (n = 220) of the referent participants died. Patients with any synucleinopathy died a median of 2 years earlier than referent participants. Patients with multiple system atrophy with parkinsonism (hazard ratio, 10.51; 95% CI, 2.92-37.82) had the highest risk of death compared with referent participants, followed by those with dementia with Lewy bodies (hazard ratio, 3.94; 95% CI, 2.61-5.94), Parkinson disease with dementia (hazard ratio, 3.86; 95% CI, 2.36-6.30), and Parkinson disease (hazard ratio, 1.75; 95% CI, 1.39-2.21). Neurodegenerative disease was the most frequent cause of death listed on the death certificate for patients, and cardiovascular disease was the most frequent cause of death among referent participants.

Conclusions and Relevance

Individuals with multiple system atrophy with parkinsonism, dementia with Lewy bodies, and Parkinson disease dementia have increased mortality compared with the general population. The mortality among persons with Parkinson disease is only moderately increased compared with the general population.

Effect of intranasal stem cell administration on the nigrostriatal system in a mouse model of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide. It affects the locomotor system, leading to a final severe disability through degeneration of dopaminergic neurons. Despite several therapeutic approaches used, no treatment has been proven to be effective; however, cell therapy may be a promising therapeutic method. In addition, the use of the intranasal (IN) route has been advocated for delivering various therapies to the brain. In the present study, the IN route was used for administration of mesenchymal stem cells (MSCs) in a mouse model of PD, with the aim to evaluate IN delivery as an alternative route for cell based therapy administration in PD. The PD model was developed in C57BL/6 mice using intraperitoneal rotenone administration for 60 consecutive days. MSCs were isolated from the mononuclear cell fraction of pooled bone marrow from C57BL/6 mice and incubated with micrometer-sized iron oxide (MPIO) particles. For IN administration, we used a 20 µl of 5×10⁵ cell suspension. Neurobehavioral assessment of the mice was performed, and after sacrifice, brain sections were stained with Prussian blue to detect the MPIO-labeled MSCs. In addition, immunohistochemical evaluation was conducted to detect tyrosine hydroxylase (TH) antibodies in the corpus striatum and dopaminergic neurons in the substantia nigra pars compacta (SNpc). The neurobehavioral assessment revealed progressive deterioration in the locomotor functions of the rotenone group, which was improved following MSC administration. Histopathological evaluation of brain sections in the rotenone+MSC group revealed successful delivery of MSCs, evidenced by positive Prussian blue staining. Furthermore, rotenone treatment led to significant decrease in dopaminergic neuron number in SNpc, as well as similar decrease in the corpus striatum fiber density. By contrast, in animals receiving IN administration of MSCs, the degeneration caused by rotenone treatment was significantly counteracted. In conclusion, the present study validated that IN delivery of MSCs may be a potential safe, easy and cheap alternative route for stem cell treatment in neurodegenerative disorders.

Traffic-related air pollution increased the risk of Parkinson's disease in Taiwan: A nationwide study

BACKGROUND

Ambient air pollution has been associated with many health conditions, but little is known about its effects on neurodegenerative diseases, such as Parkinson's disease (PD). In this study, we investigated the influence of ambient air pollution on PD in a nationwide population-based case-control study in Taiwan.

METHODS

We identified 11,117 incident PD patients between 2007 and 2009 from the Taiwanese National Health Insurance Research Database and selected 44,468 age- and gender-matched population controls from the longitudinal health insurance database. The average ambient pollutant exposure concentrations from 1998 through the onset of PD were estimated using quantile-based Bayesian Maximum Entropy models. Basing from logistic regression models, we estimated the odds ratios (ORs) and 95% confidence intervals (CIs) of ambient pollutant exposures and PD risk.

RESULTS

We observed positive associations between NO_x, CO exposures, and PD. In multi-pollutant models, for NO_x and CO above the 75th percentile exposure compared with the lowest percentile, the ORs of PD were 1.37 (95% CI=1.23-1.52) and 1.17 (95% CI=1.07-1.27), respectively.

CONCLUSIONS

This study suggests that ambient air pollution exposure, especially from traffic-related pollutants such as NO_x and CO, increases PD risk in the Taiwanese population.

Parkinson's Disease and Homocysteine: A Community-Based Study in a Folate and Vitamin B12 Deficient Population

Background. Homocysteine (Hcy) levels were higher in patients with Parkinson's disease (PD). This could be partially explained by levodopa treatment. Whether untreated PD patients have higher Hcy levels is contradictory. Methods. A community-based study was conducted using a two-stage approach for subjects ≥ 55 years to find PD patients in 3 towns of Lüliang City. Blood samples were collected. Serum Hcy, folate, and vitamin B12 concentrations were measured. For each untreated PD patient, 5 controls were selected matched with age and sex to evaluate the relationship between Hcy levels and PD. Results. Of 6338 eligible residents, 72.7% participated in the study. 31 PD cases were identified. The crude prevalence of PD for people ≥ 55 years was 0.67%. Blood samples were collected from 1845 subjects, including 17 untreated PD patients. There was no difference for concentrations of serum Hcy, folate, and vitamin B12 between cases and controls (P > 0.05). In univariate and multivariate analysis, there was significant inverse relation between PD and current smoking (P < 0.05). No other factor was significant statistically. Conclusions. The prevalence of PD was comparable to earlier studies in China. Hyperhomocysteinemia was not a risk factor of PD, as well as folate and vitamin B12 deficiency.

Premotor Symptoms as Predictors of Outcome in Parkinsons Disease: A Case-Control Study

Background

To evaluate the association between the premotor symptoms and the prognosis of PD.

Methods

A total of 1213 patients who were diagnosed of PD from January 2001 to December 2008 were selected from the Taiwan’s National Health Insurance Research Database. Patients were traced back to determine the presence of premotor symptoms, including rapid eye movement sleep behavior disorder (RBD), depression, and constipation. Cox’s regression analysis was used to detect the risks between the occurrence of premotor symptoms and the outcome (including death, psychosis, accidental injury, dementia and aspiration pneumonia). In addition, the association between premotor symptoms and levodopa equivalent dosage (LED) was examined.

Results

Higher occurrence of death, dementia and aspiration pneumonia were identified in PD patients with premotor symptoms than without premotor symptoms (HR 1·69, 95% CI 1·34–2·14, p <0·001 for death; HR 1·63, 95% CI 1·20–2·22, p = 0·002 for dementia; HR 2·45, 95% CI 1·42–4·21, p = 0·001 for aspiration pneumonia). In a comorbidities-stratified analysis, PD patients with premotor symptoms showed significantly high risks of mortality and morbidity (dementia and aspiration pneumonia), especially in the absence of comorbidities. Independent predictors of mortality in PD were found to be higher age, male sex, constipation, RBD, RBD with constipation and depression, and diabetes. Furthermore, no significant differences of LED and subsequent accidental injury were noted between PD patient with or without premotor symptoms.

Conclusion

Premotor symptoms seem to be not merely risk factors, but also prognostic factors of PD.

Variations in Incidence and Prevalence of Parkinson's Disease in Taiwan: A Population-Based Nationwide Study

Demographic, socioeconomic, and urbanization level variations in Parkinson's disease (PD) are rarely investigated, especially in Asia. This study describes an eight-year trend in PD incidence and prevalence in Taiwan as well as assessing the effects of sociodemographics and urbanization on the incidence and prevalence of PD. The data analyzed were acquired from the Taiwan National Health Insurance Research Database (NHIRD) entries between 2002 and 2009. The calendar year, sex, and age-specific rates were standardized, and the effects of the sociodemographics and urbanization on PD were assessed using Poisson regression analysis. PD incidence and prevalence showed a significantly increasing trend, with a greater magnitude noted for prevalence than for incidence (87.3% versus 9.2%). The PD incidence and prevalence increased with age and were slightly higher in men than in women. The people who were not under the labor force (i.e., dependents) or with lower monthly incomes were at significantly increased adjusted incidence rate ratio (1.50–1.56) and adjusted prevalence rate ratio (1.66–1.71) of PD. Moreover, significantly higher PD incidence and prevalence were noted in areas with lesser urbanization. This information emphasizes the need for preventive and clinical care strategies targeting the segment of Taiwanese population that exhibited a greater incidence and prevalence of PD.

Risk factors for pneumonia among patients with Parkinson's disease: a Taiwan nationwide population-based study

OBJECTIVE

Pneumonia is the leading cause of death in patients with Parkinson's disease (PD). However, few studies have been performed to explore the risk factors for pneumonia development in patients with PD.

METHODS

We conducted a nationwide population-based cohort study of patients with PD to identify the risk factors for these patients developing pneumonia. Participants with newly diagnosed PD between 2000 and 2009 were enrolled from the 2000-2010 National Health Insurance Research Database in Taiwan. We compared patients with PD with an incidence of hospitalization with pneumonia vs those without, and Cox proportional hazard models were used to estimate the risk of pneumonia.

RESULTS

Of the 2,001 enrolled patients (mean follow-up duration 5.8 years, range: 2.7-14.7 years), 381 (19.0%) had an incidence of hospitalization with pneumonia during the study period. Multivariate Cox proportional hazards analysis identified older age group (≥80 years of age, hazard ratio [HR] =3.15 [95% confidence interval 2.32-4.28]), male sex (HR =1.59 [1.29-1.96]), certain geographic regions (northern, HR =1.36 [1.04-1.78], southern and eastern, HR =1.40 [1.05-1.88]), rural areas (HR =1.34 [1.05-1.72]), chronic heart failure (HR =1.53 [1.02-2.29]), and chronic kidney disease (HR =1.39 [1.03-1.90]) as risk factors for hospitalization with pneumonia in patients with PD. However, treatment for dental caries was a protective factor (HR =0.80 [0.64-0.99]).

CONCLUSION

The results of this study highlight risk factors that are associated with hospitalization with pneumonia, and, for the first time, suggest a link between treated dental caries and a diminished risk of hospitalization with pneumonia in patients with PD.

Mortality in Iranian Patients with Parkinson's Disease: Cumulative Impact of Cardiovascular Comorbidities as One Major Risk Factor

Mortality rate, life expectancy, survival, and the impact of comorbidities on them in people with Parkinson's disease (PD) need to be assessed in settings with different sociodemographic backgrounds. We investigated mortality features in Iranian PD patients focusing on the role of cardiovascular multimorbidity on their survival. Data on mortality and comorbidity profile was gathered in a cohort of 190 individuals with idiopathic PD referred to a Movement Disorders Clinic. Standardized mortality ratio (SMR) compared to the Tehran general population was 3.44 and the life expectancy at birth was 67.4 (95% CI: 59.1-75.8) yr. Patients with at least one cardiovascular comorbidity had a shorter survival time after PD onset (14.0 versus 29.2 yr, p = 0.012). The hazard ratio for death increased 2.8 times (95% CI: 1.5-5.2, p = 0.002) with one additional cardiovascular comorbidity. Among all comorbid conditions, stroke showed the strongest independent effect on mortality in PD patients [HR = 13.1 (95% CI: 2.4-71.7), p = 0.003]. Conclusively, life expectancy was slightly lower in Iranian PD patients compared to the general population, while the SMR was high. Cardiometabolic multimorbidity substantially decreased survival in people with PD. Our study highlights the need for assessment, prevention, and treatment of cardiovascular morbidities in parkinsonian patients, given their effect on survival.

Time trends in the prevalence and incidence of Parkinson's disease in Taiwan: A nationwide, population-based study

BACKGROUND/PURPOSE

Identifying trends in the prevalence and incidence of Parkinson's disease (PD) may yield information that supports public health goals. Our aim was to evaluate time-trend changes in the prevalence and incidence of PD in Taiwan between 2004 and 2011.

METHODS

This retrospective, nationwide, longitudinal study used the Taiwan National Health Insurance Research Database to identify patients with PD from 2004 to 2011 based on having ICD-9-CM diagnostic codes, which were assigned by neurologists, and being prescribed PD medication. Annual incidence and prevalence were calculated, and time-trend analyses were estimated assuming a Poisson distribution.

RESULTS

Over the study period, 19,302 patients in 2004 and 41,606 patients in 2011 fulfilling the study criteria for PD were included in the analysis. The average age-standardized prevalence of PD per 100,000 of population was 84.8 in 2004 and 147.7 in 2011, with a 7.9% yearly increase. Increasing prevalence trends of PD were statistically significant (p < 0.001) in all age groups, with the steepest rate among those aged ≥ 80 years. In contrast, the average age-standardized incidence of PD decreased steadily from 35.3 per 100,000 in 2005 to 28.8 per 100,000 in 2011. The incidence rate was higher in men than in women, and increased with age.

CONCLUSION

We identified an increasing trend in the annual prevalence rates of PD from 2004 to 2011; however, the substantial decline in the incidence of PD suggests that some major environmental risk factors for PD were removed from this population during this time period.

Do physical exercise and reading reduce the risk of Parkinson's disease? a cross-sectional study on factors associated with Parkinson's disease in elderly Chinese veterans

BACKGROUND

The purpose of this study was to investigate risk factors for and factors protecting against Parkinson's disease (PD) in elderly Chinese veterans.

METHODS

Using a database containing detailed information on the health status of the nervous system in elderly Chinese veterans, univariate and multivariate analyses of factors that may be associated with PD were performed. Univariate analysis of qualitative data was done using the Pearson Chi-square and Fisher's exact tests, and the Mann-Whitney U nonparametric test was used for univariate analysis of quantitative data. Multivariate logistic regression analysis was used to identify independent risk factors for and factors protecting against PD in elderly Chinese veterans.

RESULTS

A total of 9,676 elderly Chinese veterans were enrolled, including 228 cases with PD and 183 cases with Parkinson's syndrome, with 9,265 non-PD subjects serving as controls. Age (odds ratio [OR] 1.343, 95% confidence interval [CI] 1.028-1.755) and medical history of essential tremor (OR 1.228, 95% CI 1.081-1.396) were identified as independent risk factors for PD, with age being the most important risk factor. Physical exercise (OR 0.478, 95% CI 0.355-0.643) and reading (OR 0.513, 95% CI 0.357-0.735) were identified as independent factors protecting against PD, and physical exercise showed better protection against PD relative to reading. Smoking, alcohol use, anemia, cerebral trauma, education level, and electromagnetic field exposure showed no association with PD.

CONCLUSION

Physical exercise and reading may be independent factors that protect against PD among elderly Chinese veterans, while advancing age and medical history of essential tremor may be independent risk factors for PD. This study was cross-sectional, so further research is needed to confirm its results.

Systematic review of the prevalence and incidence of Parkinson's disease in the People's Republic of China

BACKGROUND

Parkinson's disease (PD) is a common neurodegenerative disease, and obtaining accurate epidemiological data for this disease is very important for policy-making in public health. The purpose of this study was to determine the prevalence and incidence of PD in the People's Republic of China and explore possible future research directions.

METHODS

We systematically retrieved studies of the prevalence and incidence of PD in the People's Republic of China, Taiwan, and Hong Kong, and standardized the data according to the world's population in 2000.

RESULTS

Fifteen eligible studies were retrieved. Most were cross-sectional studies, and two thirds of the research was from the People's Republic of China. The prevalence of PD was reported in all the studies, but only two studies reported incidence data. The prevalence of PD in the People's Republic of China ranged from 16 to 440.3/100,000, and the annual incidence ranged from 1.5 to 8.7/100,000.

CONCLUSION

The prevalence of PD in the People's Republic of China has been widely investigated in the studies published to date. However, due to methodological heterogeneity, the data reported by the different studies are not comparable. There is still a lack of information on the incidence of PD in the People's Republic of China. Therefore, future research is required to answer this question.

Bilateral subthalamic stimulation for advanced Parkinson disease: early experience at an Eastern center

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) can improve the life quality of patients with advanced Parkinson disease (PD). However, previous studies have stemmed mainly from Western centers. Present study analyzed the 6-month outcomes of bilateral STN-DBS therapy that were observed during a 9-year period at a Taiwanese institute. We retrospectively reviewed 72 consecutive patients, whose mean disease history was 8 years when they underwent surgery. The median "drug-off" Hoehn and Yahr stage was 3. The STN was targeted using T2-weighted magnetic resonance imaging and electrophysiological guidance. The over-time mean differences in the Unified PD Rating Scale (UPDRS) scores and daily levodopa-equivalent dose (LED) were assessed using the repeated measurements ANOVA at 3 and 6 months relative to those of presurgical drug-off baseline. At 6 months postsurgery, the mean UPDRS total, Part II and Part III subscores significantly decreased by 27, 30 and 25 %, respectively, with clinically high effect size. Tremors were markedly (66 %) ameliorated. Moreover, problems of akinesia, rigidity, and locomotion were significantly improved by 20 %. The mean daily LED needs decreased by 25 %; thus, drug-induced dyskinesia was markedly (80 %) diminished. STN-DBS therapy could provide similarly effective impacts to Eastern and Western PD patients. Preoperative optimal selection of patients and postoperative delicate programming ensure a better surgical improvement.

Mutational analysis of angiogenin gene in Parkinson's disease

Mutations in the angiogenic factor, angiogenin (ANG), have been identified in patients with both familial and sporadic amyotrophic lateral sclerosis (ALS) and are thought to have a neuroprotective function. Parkinsonism has been noted in kindreds with ANG mutations and variants in the ANG gene have been found to associate with PD in two Caucasian populations. We therefore hypothesized that mutations in ANG may also contribute to idiopathic Parkinson's disease (PD). We sequenced ANG gene in a total of 1498 participants comprising 750 PD patients and 748 age/gender matched controls from Taiwan. We identified one novel synonymous substitution, c.C100T (p.L10L), in a single heterozygous state in one PD patient, which was not observed in controls. The clinical phenotypes and [^99mTc]-TORDAT-SPECT images of the p.L10L carrier were similar to that seen in idiopathic PD. In addition, we also identified one common variant, c.T330G (p.G110G, rs11701), which was previously reported to associate with PD risk in Caucasians. However, the frequency of TG/GG genotype was comparable between PD cases and controls (odds ratio: 0.85, 95% confidence interval: 0.29–2.55, P = 0.78). Our results did not support that ANG rs11701 variant is a genetic risk factor for PD in our population. We conclude that mutations in ANG are not a common cause for idiopathic PD.

Clinical features of drug-induced parkinsonism based on [18F] FP-CIT positron emission tomography

Drug-induced parkinsonism (DIP) is the common cause of parkinsonism. It is difficult to make a differentiation between DIP and Parkinson's disease (PD) because there are no notable differences in the clinical characteristics between the two entities. In this study, we examined the relationship between the characteristics of [(18)F] fluorinated-N-3-fluoropropyl-2-β-carboxymethoxy-3-β-(4-iodophenyl)nortropane (FP-CIT) positron emission tomography (PET) images and clinical features in DIP patients. We retrospectively studied 76 patients with DIP who underwent [(18)F] FP-CIT PET. We also enrolled 16 healthy controls who underwent it. We compared the clinical characteristics between the DIP patients with normal [(18)F] FP-CIT PET scans and those with abnormal ones. Symmetric parkinsonism was more frequent in the patients with normal [(18)F] FP-CIT PET scans as compared with those with abnormal ones. Interval from drug intake to onset of parkinsonism was longer in the patients with abnormal [(18)F] FP-CIT PET scans as compared with those with normal ones. A semi-quantitative analysis showed that specific to non-specific binding ratios in the putamen was lower in the patients with abnormal [(18)F] FP-CIT PET scans as compared with those with normal ones and the age-matched control group. Our results suggest that symmetric parkinsonism was more prevalent, and the duration of drug exposure before the onset of parkinsonism was shorter in the patients with normal [(18)F] FP-CIT PET scans as compared with those with abnormal ones.

The prevalence of Parkinson's disease: a systematic review and meta-analysis

Parkinson's Disease (PD) is a common neurodegenerative disorder. We sought to synthesize studies on the prevalence of PD to obtain an overall view of how the prevalence of this disease varies by age, by sex, and by geographic location. We searched MEDLINE and EMBASE for epidemiological studies of PD from 1985 to 2010. Data were analyzed by age group, geographic location, and sex. Geographic location was stratified by the following groups: 1) Asia, 2) Africa, 3) South America, and 4) Europe/North America/Australia. Meta-regression was used to determine whether a significant difference was present between groups. Forty-seven studies were included in the analysis. Meta-analysis of the worldwide data showed a rising prevalence of PD with age (all per 100,000): 41 in 40 to 49 years; 107 in 50 to 59 years; 173 in 55 to 64 years; 428 in 60 to 69 years; 425 in 65 to 74 years; 1087 in 70 to 79 years; and 1903 in older than age 80. A significant difference was seen in prevalence by geographic location only for individuals 70 to 79 years old, with a prevalence of 1,601 in individuals from North America, Europe, and Australia, compared with 646 in individuals from Asia (P < 0.05). A significant difference in prevalence by sex was found only for individuals 50 to 59 years old, with a prevalence of 41 in females and 134 in males (P < 0.05). PD prevalence increases steadily with age. Some differences in prevalence by geographic location and sex can be detected.

Sudden death in Parkinson's disease: a retrospective autopsy study

The aim of this paper is to reveal the causes of death and to verify sudden death of Parkinson's disease (PD) in an autopsy study. We reviewed the clinical data and the causes of death in 16 PD patients who had postmortem examinations. Prior to autopsy, nine patients died of known causes: five patients died of aspiration pneumonia, two of myocardial infarction, one of asphyxia, and one of dilated cardiomyopathy. Autopsy confirmed that the putative causes of death were compatible with the pathological ones. The remaining seven patients died suddenly of unknown causes. Autopsy revealed that the causes of death were asphyxia in two patients and perforation of a duodenal ulcer in one patient. Autopsy did not determine the causes of unknown death in the remaining four patients. Consequently, autopsy revealed that eight patients died of swallowing problems such as aspiration pneumonia and asphyxia, four of sudden death, three of cardiac problems, and one of a gastrointestinal problem. Although there was a bias that all patients had a postmortem examination, our study revealed that several PD patients died of sudden death without any satisfactory causes of death determined even by autopsy. Therefore, we propose that a non-negligible number of PD patients die of sudden death.

Hearing loss may be a non-motor feature of Parkinson's disease in older people in Taiwan

BACKGROUND AND PURPOSE

The aim of this study was to explore whether hearing loss is associated with the risk of Parkinson's disease in the elderly in Taiwan.

METHODS

Using claims data of the Taiwan National Health Insurance Program, 4976 patients (aged 65 years or older) with newly diagnosed hearing loss from 2000 to 2010 were identified and 19 904 subjects without hearing loss were randomly selected as comparisons, frequency matched by sex, age and index year of diagnosing hearing loss. The incidence of Parkinson's disease by the end of 2010 and the associated risk factors were investigated.

RESULTS

The incidence of Parkinson's disease in the hearing loss group was 1.77-fold higher than that in the non-hearing-loss group (3.11 vs. 1.76 per 1000 person-years). After controlling for confounding factors, the adjusted hazard ratio (HR) of Parkinson's disease was 1.53 (95% CI 1.17, 1.99) for the hearing loss group compared with the non-hearing-loss group. Male sex (HR = 1.33, 95% CI 1.02, 1.74), age (for each year, HR = 1.06, 95% CI 1.04, 1.09), hypertension (HR = 1.70, 95% CI 1.26, 2.30) and cerebrovascular disease (HR = 1.78, 95% CI 1.37, 2.32) were also significantly associated with the risk of Parkinson's disease.

CONCLUSIONS

Hearing loss correlates with an increased risk of Parkinson's disease in the elderly. Further studies are needed to confirm whether hearing loss could be a non-motor feature of Parkinson's disease.

Mortality in levodopa-treated Parkinson's disease

Parkinson's disease (PD) is associated with increased mortality despite many advances in treatment. Following the introduction of levodopa in the late 1960's, many studies reported improved or normalized mortality rates in PD. Despite the remarkable symptomatic benefits provided by levodopa, multiple recent studies have demonstrated that PD patients continue to die at a rate in excess of their peers. We undertook this retrospective study of 211 deceased PD patients to determine the factors associated with mortality in levodopa-treated PD. Our findings confirm that PD is associated with increased mortality in both men and women. Unlike the majority of other mortality studies, we found that women have a greater reduction in lifespan compared to men. We also found that patients with early onset PD (onset at the age of 50 or before) have reduced survival relative to PD patients with later ages of onset. A final important finding is that survival is equal in PD patients treated with levodopa early (within 2 years or less of PD onset) versus later.