Donepezil in Parkinson's disease dementia: a randomized, double-blind efficacy and safety study

The effect of anticholinergic drugs on cognition of patients with Parkinson's disease: a cohort study from the Egyptian population

BACKGROUND

Cognitive dysfunction is a non-motor manifestation of Parkinson's disease (PD). We aimed to determine the frequency and patterns of cognitive dysfunction in treated patients with PD and their predictors.

RESEARCH DESIGN AND METHODS

This study included 80 patients (male = 48; female = 32) and 30 healthy individuals. They underwent neuropsychiatric evaluations. Measurements included Beck's depression inventory - II (BDI-II), mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA).

RESULTS

Patients had mean age of 55.56 ± 9.06 yrs, duration of PD of 4.86 ± 2.71 yrs and Hoehn and Yahr Scoring of 2.19 ± 0.89. They were on levodopa/carbidopa therapy and adjuvant therapy with benztropine mesylate, an anticholinergic drug, (n = 51) or amantadine sulfate, a dopaminergic drug, (n = 29). Sixteen (20%) had moderate depressive symptoms. Mild and moderate cognitive impairments were reported in 38.8% and 28.8% (by MMSE) and 46.3% and 31.3% (by MoCA). Patients had lower global cognitive scoring (p = 0.0001) and scorings of different cognitive functions (naming, attention, language, abstraction, memory and orientation) than controls. Patients treated with benztropine had lower cognition than with amantadine. Correlation analyses showed that lower cognition was only associated with chronic PD and its treatment (p = 0.0001).

CONCLUSIONS

Cognitive dysfunction is common with PD (77.5%) particularly with anticholinergic drugs. De-prescription of anticholinergics is recommended for patients with PD.

Novel and experimental therapeutics for the management of motor and non-motor Parkinsonian symptoms

BACKGROUND  : Both motor and non-motor symptoms of Parkinson's disease (PD) have a substantial detrimental influence on the patient's quality of life. The most effective treatment remains oral levodopa. All currently known treatments just address the symptoms; they do not completely reverse the condition.

METHODOLOGY

In order to find literature on the creation of novel treatment agents and their efficacy for PD patients, we searched PubMed, Google Scholar, and other online libraries.

RESULTS

According to the most recent study on Parkinson's disease (PD), a great deal of work has been done in both the clinical and laboratory domains, and some current scientists have even been successful in developing novel therapies for PD patients.

CONCLUSION

The quality of life for PD patients has increased as a result of recent research, and numerous innovative medications are being developed for PD therapy. In the near future, we will see positive outcomes regarding PD treatment.

Tele-Neuropsychology: From Science to Policy to Practice

OBJECTIVE

The primary aim of this paper is to accelerate the number of randomized experimental studies of the reliability and validity in-home tele-neuropsychological testing (tele-np-t).

METHOD

We conducted a critical review of the tele-neuropsychology literature. We discuss this research in the context of the United States' public and private healthcare payer systems, including the Centers for Medicare & Medicaid Services (CMS) and Current Procedural Terminology (CPT) coding system's telehealth lists, and existing disparities in healthcare access.

RESULTS

The number of tele-np publications has been stagnant since the onset of the COVID-19 pandemic. There are less published experimental studies of tele-neuropsychology (tele-np), and particularly in-home tele-np-t, than other tele-np publications. There is strong foundational evidence of the acceptability, feasibility, and reliability of tele-np-t, but relatively few studies of the reliability and validity of in-home tele-np-t using randomization methodology.

CONCLUSIONS

More studies of the reliability and validity of in-home tele-np-t using randomization methodology are necessary to support inclusion of tele-np-t codes on the CMS and CPT telehealth lists, and subsequently, the integration and delivery of in-home tele-np-t services across providers and institutions. These actions are needed to maintain equitable reimbursement of in-home tele-np-t services and address the widespread disparities in healthcare access.

Insights into the management of Lewy body dementia: a scoping review

Lewy body dementia (LBD) is situated at the convergence of neurodegenerative disorders, posing an intricate and diverse clinical dilemma. The accumulation of abnormal protein in the brain, namely, the Lewy body causes disturbances in typical neural functioning, leading to a range of cognitive, motor, and mental symptoms that have a substantial influence on the overall well-being and quality of life of affected individuals. There is no definitive cure for the disease; however, several nonpharmacological and pharmacological modalities have been tried with questionable efficacies. The aim of this study is to figure out the role of different interventional strategies in the disease. Donepezil, rivastigmine, memantine, and galantamine were the commonly used drugs for LBD. Together with that, levodopa, antipsychotics, armodafinil, piracetam, and traditional medications like yokukansan were also used, when indicated. Talking about nonpharmacological measures, exercise, physical therapy, multicomponent therapy, occupational therapy, psychobehavioral modification, transcranial stimulation, and deep brain stimulation have been used with variable efficacies. Talking about recent advances in the treatment of LBD, various disease-modifying therapies like ambroxol, neflamapimod, irsenontrine, nilotinib, bosutinib, vodobatinib, clenbuterol, terazosin, elayta, fosgonimeton, and anle138b are emerging out. However, there drugs are still in the different phases of clinical trials and are not commonly used in clinical practice. With the different pharmacological and nonpharmacological modalities we have for treatment of LBD, all of them offer symptomatic relief only. Being a degenerative disease, definite cure of the disease can only be possible with regenerative measures.

A multiple hits hypothesis for memory dysfunction in Parkinson disease

Cognitive disorders are increasingly recognized in Parkinson disease (PD), even in early disease stages, and memory is one of the most affected cognitive domains. Classically, hippocampal cholinergic system dysfunction was associated with memory disorders, whereas nigrostriatal dopaminergic system impairment was considered responsible for executive deficits. Evidence from PD studies now supports involvement of the amygdala, which modulates emotional attribution to experiences. Here, we propose a tripartite model including the hippocampus, striatum and amygdala as key structures for cognitive disorders in PD. First, the anatomo-functional relationships of these structures are explored and experimental evidence supporting their role in cognitive dysfunction in PD is summarized. We then discuss the potential role of α-synuclein, a pathological hallmark of PD, in the tripartite memory system as a key mechanism in the pathogenesis of memory disorders in the disease.

Cholinesterase inhibitors and falls, syncope and injuries in patients with cognitive impairment: a systematic review and meta-analysis

BACKGROUND

Cholinesterase inhibitors are commonly used to treat patients with neurocognitive disorders, who often have an elevated risk of falling. Effective use of these medications requires a thoughtful assessment of risks and benefits.

OBJECTIVE

To provide an update on previous reviews and determine the association between cholinesterase inhibitors and falls, syncope, fracture and accidental injuries in patients with neurocognitive disorders.

METHODS

Embase, MEDLINE, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature and AgeLine were systematically searched through March 2023 to identify all randomised controlled trials of cholinesterase inhibitors (donepezil, galantamine, rivastigmine) in patients with cognitive impairment. Corresponding authors were contacted for additional data necessary for meta-analysis. Inclusion criteria consisted of adults ≥19 years, with a diagnosis of dementia, Parkinson's disease, mild cognitive impairment or traumatic brain injury. Data were extracted in duplicate for the aforementioned primary outcomes and all outcomes were analysed using random-effects meta-analysis.

RESULTS

Fifty three studies (30 donepezil, 14 galantamine, 9 rivastigmine) were included providing data on 25, 399 patients. Cholinesterase inhibitors, compared to placebo, were associated with reduced risk of falls (risk ratio [RR] 0.84 [95% confidence interval [CI] = 0.73-0.96, P = 0.009]) and increased risk of syncope (RR 1.50 [95% CI = 1.02-2.21, P = 0.04]). There was no association with accidental injuries or fractures.

CONCLUSION

In patients with neurocognitive disorders, cholinesterase inhibitors were associated with decreased risk of falls, increased risk of syncope and no association with accidental trauma or fractures. These findings will help clinicians better evaluate risks and benefits of cholinesterase inhibitors.

Parkinson's disease updates: Addressing the pathophysiology, risk factors, genetics, diagnosis, along with the medical and surgical treatment

After only Alzheimer's disease (AD), Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. The incidence of this disease increases with age, especially for those above 70 years old. There are many risk factors that are well-established in the contribution to the development of PD, such as age, gender, ethnicity, rapid eye movement sleep disorder, high consumption of dairy products, traumatic brain injury, genetics, and pesticides/herbicides. Interestingly, smoking, consumption of caffeine, and physical activities are the protective factors of PD. A deficiency of dopamine in the substantia nigra of the brainstem is the main pathology. This, subsequently, alters the neurotransmitter, causing an imbalance between excitatory and inhibitory signals. In addition, genetics is also involved in the pathogenesis of the disease. As a result, patients exhibit characteristic motor symptoms such as tremors, stiffness, bradykinesia, and postural instability, along with non-motor symptoms, including dementia, urinary incontinence, sleeping disturbances, and orthostatic hypotension. PD may resemble other diseases; therefore, it is important to pay attention to the diagnosis criteria. Parkinson's disease dementia can share common features with AD; this can include behavioral as well as psychiatric symptoms, in addition to the pathology being protein aggregate accumulation in the brain. For PD management, the administration of pharmacological treatment depends on the motor symptoms experienced by the patients. Non-pharmacological treatment plays a role as adjuvant therapy, while surgical management is indicated in chronic cases. This paper aims to review the etiology, risk factors, protective factors, pathophysiology, signs and symptoms, associated conditions, and management of PD.

Cholinesterase Inhibitors for Treatment of Psychotic Symptoms in Alzheimer Disease and Parkinson Disease: A Meta-analysis

Importance

Psychotic symptoms greatly increase the burden of disease for people with neurodegenerative disorders and their caregivers. Cholinesterase inhibitors (ChEIs) may be effective treatment for psychotic symptoms in these disorders. Previous trials only evaluated neuropsychiatric symptoms as a secondary and an overall outcome, potentially blurring the outcomes noted with ChEI use specifically for psychotic symptoms.

Objective

To quantitatively assess the use of ChEIs for treatment of individual neuropsychiatric symptoms, specifically hallucinations and delusions, in patients with Alzheimer disease (AD), Parkinson disease (PD), and dementia with Lewy bodies (DLB).

Data Sources

A systematic search was performed in PubMed (MEDLINE), Embase, and PsychInfo, without year restrictions. Additional eligible studies were retrieved from reference lists. The final search cutoff date was April 21, 2022.

Study Selection

Studies were selected if they presented the results of placebo-controlled randomized clinical trials, including at least 1 donepezil, rivastigmine, or galantamine treatment arm in patients with AD, PD, or DLB; if they applied at least 1 neuropsychiatric measure including hallucinations and/or delusions; and if a full-text version of the study was available in the English language. Study selection was performed and checked by multiple reviewers.

Data Extraction and Synthesis

Original research data were requested on eligible studies. A 2-stage meta-analysis was then performed, using random-effects models. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed for extracting data and assessing the data quality and validity. Data extraction was checked by a second reviewer.

Main Outcomes and Measures

Primary outcomes were hallucinations and delusions; secondary outcomes included all other individual neuropsychiatric subdomains as well as the total neuropsychiatric score.

Results

In total, 34 eligible randomized clinical trials were selected. Individual participant data on 6649 individuals (3830 [62.6%] women; mean [SD] age, 75.0 [8.2] years) were obtained from 17 trials (AD: n = 12; PD: n = 5; individual participant data were not available for DLB). An association with ChEI treatment was shown in the AD subgroup for delusions (-0.08; 95% CI, -0.14 to -0.03; P = .006) and hallucinations (-0.09; 95% CI, -0.14 to -0.04; P = .003) and in the PD subgroup for delusions (-0.14; 95% CI, -0.26 to -0.01; P = .04) and hallucinations (-0.08, 95% CI -0.13 to -0.03; P = .01).

Conclusions and Relevance

The results of this individual participant data meta-analysis suggest that ChEI treatment improves psychotic symptoms in patients with AD and PD with small effect sizes.

Determinants of approved acetylcholinesterase inhibitor response outcomes in Alzheimer's disease: relevance for precision medicine in neurodegenerative diseases

Acetylcholinesterase inhibitors (ChEI) are the global standard of care for the symptomatic treatment of Alzheimer's disease (AD) and show significant positive effects in neurodegenerative diseases with cognitive and behavioral symptoms. Although experimental and large-scale clinical evidence indicates the potential long-term efficacy of ChEI, primary outcomes are generally heterogeneous across outpatient clinics and regional healthcare systems. Sub-optimal dosing or slow tapering, heterogeneous guidelines about the timing for therapy initiation (prodromal versus dementia stages), healthcare providers' ambivalence to treatment, lack of disease awareness, delayed medical consultation, prescription of ChEI in non-AD cognitive disorders, contribute to the negative outcomes. We present an evidence-based overview of determinants, spanning genetic, molecular, and large-scale networks, involved in the response to ChEI in patients with AD and other neurodegenerative diseases. A comprehensive understanding of cerebral and retinal cholinergic system dysfunctions along with ChEI response predictors in AD is crucial since disease-modifying therapies will frequently be prescribed in combination with ChEI. Therapeutic algorithms tailored to genetic, biological, clinical (endo)phenotypes, and disease stages will help leverage inter-drug synergy and attain optimal combined response outcomes, in line with the precision medicine model.

Systematic review of pharmacological interventions for people with Lewy body dementia

OBJECTIVE

Lewy body dementia (LBD) is the second most common neurodegenerative dementia, and it causes earlier mortality and more morbidity than Alzheimer's disease. Reviewing current evidence on its pharmacological management is essential for developing evidence-based clinical guidelines, and for improving the quality of its clinical care. Hence, we systematically reviewed all studies that investigated the efficacy of any medication for managing various symptoms of LBD.

METHOD

We identified eligible studies by searching 15 databases comprehensively. We completed quality assessment, extracted relevant data, and performed GRADE assessment of available evidence. We conducted meta-analyses when appropriate (PROSPERO:CRD42020182166).

RESULTS

We screened 18,884 papers and included 135 studies. Our meta-analyses confirmed level-1 evidence for Donepezil's efficacy of managing cognitive symptoms of dementia with Lewy bodies (DLB) (SMD = 0.63; p < 0.001) and Parkinson's Disease Dementia (PDD) (SMD = 0.43; p < 0.01), and managing hallucinations in DLB (SMD=-0.52; p = 0.02). Rivastigmine and Memantine have level-2 evidence for managing cognitive and neuropsychiatric symptoms of DLB. Olanzapine and Yokukansan have similar evidence for managing DLB neuropsychiatric symptoms. Level-2 evidence support the efficacy of Rivastigmine and Galantamine for managing cognitive and neuropsychiatric symptoms of PDD.

CONCLUSION

We list evidence-based recommendations for the pharmacological management of DLB and PDD, and propose specific clinical guidelines for improving their clinical management.

Supplemental data for this article can be accessed online at https://doi.org/10.1080/13607863.2022.2032601 .

An Update on Nondopaminergic Treatments for Motor and Non-motor Symptoms of Parkinson's Disease

Nondopaminergic neurotransmitters such as adenosine, norepinephrine, serotonin, glutamate, and acetylcholine are all involved in Parkinson's disease (PD) and promote its symptoms. Therefore, nondopaminergic receptors are key targets for developing novel preparations for the management of motor and non-motor symptoms in PD, without the potential adverse events of dopamine replacement therapy. We reviewed English-written articles and ongoing clinical trials of nondopaminergic treatments for PD patients till 2014 to summarize the recent findings on nondopaminergic preparations for the treatment of PD patients. The most promising research area of nondopaminergic targets is to reduce motor complications caused by traditional dopamine replacement therapy, including motor fluctuations and levodopa-induced dyskinesia. Istradefylline, Safinamide, and Zonisamide were licensed for the management of motor fluctuations in PD patients, while novel serotonergic and glutamatergic agents to improve motor fluctuations are still under research. Sustained- release agents of Amantadine were approved for treating levodopa induced dyskinesia (LID), and serotonin 5HT1B receptor agonist also showed clinical benefits to LID. Nondopaminergic targets were also being explored for the treatment of non-motor symptoms of PD. Pimavanserin was approved globally for the management of hallucinations and delusions related to PD psychosis. Istradefylline revealed beneficial effect on daytime sleepiness, apathy, depression, and lower urinary tract symptoms in PD subjects. Droxidopa may benefit orthostatic hypotension in PD patients. Safinamide and Zonisamide also showed clinical efficacy on certain non-motor symptoms of PD patients. Nondopaminergic drugs are not expected to replace dopaminergic strategies, but further development of these drugs may lead to new approaches with positive clinical implications.

Interlinked role of ASN, TDP-43 and Miro1 with parkinopathy: Focus on targeted approach against neuropathy in parkinsonism

Parkinsonism is a complex neurodegenerative disease that is difficult to differentiate because of its idiopathic and unknown origins. The hereditary parkinsonism known as autosomal recessive-juvenile parkinsonism (AR-JP) is marked by tremors, dyskinesias, dystonic characteristics, and manifestations that improve sleep but do not include dementia. This was caused by deletions and point mutations in PARK2 (chromosome 6q25.2-27). Diminished or unusual sensations (paresthesias), loss of neuron strength both in the CNS and peripheral nerves, and lack of motor coordination are the hallmarks of neuropathy in parkinsonism. The incidence of parkinsonism during oxidative stress and ageing is associated with parkinopathy. Parkinopathy is hypothesized to be triggered by mutation of the parkin (PRKN) gene and loss of normal physiological functions of PRKN proteins, which triggers their pathogenic aggregation due to conformational changes. Two important genes that control mitochondrial health are PRKN and phosphatase and tensin homologue deleted on chromosome 10-induced putative kinase 1 (PINK1). Overexpression of TAR DNA-binding protein-43 (TDP-43) increases the aggregation of insoluble PRKN proteins in OMM. Foreign α-synuclein (ASN) promotes parkinopathy via S-nitrosylation and hence has a neurotoxic effect on dopaminergic nerves. Miro1 (Miro GTPase1), a member of the RAS superfamily, is expressed in nerve cells. Due to PINK1/PRKN and Miro1's functional relationship, an excess of mitochondrial calcium culminates in the destruction of dopaminergic neurons. An interlinked understanding of TDP-43, PINK1/PRKN, ASN, and Miro1 signalling in the communication among astrocytes, microglia, neurons, and immune cells within the brain explored the pathway of neuronal death and shed light on novel strategies for the diagnosis and treatment of parkinsonism.

Donepezil Beyond Alzheimer's Disease? A Narrative Review of Therapeutic Potentials of Donepezil in Different Diseases

Donepezil hydrochloride is an acetylcholine esterase inhibitor studied and approved to treat Alzheimer's disease (AD). However, this drug can have positive therapeutic potential in treating different conditions, including various neurodegenerative disorders such as other types of dementia, multiple sclerosis, Parkinson's disease, psychiatric and mood disorders, and even infectious diseases. Hence, this study reviewed the therapeutic potential of this drug in treating Alzheimer's and other diseases by reviewing the articles from databases including Web of Science, Scopus, PubMed, Cochrane, and Science Direct. It was shown that donepezil could affect the pathophysiology of these diseases via mechanisms such as increasing the concentration of acetylcholine, modulating local and systemic inflammatory processes, affecting acetylcholine receptors like nicotinic and muscarinic receptors, and activating various cellular signaling via receptors like sigma-1 receptors. Despite many therapeutic potentials, this drug has not yet been approved for treating non-Alzheimer's diseases, and more comprehensive studies are needed.

The efficacy of pharmacological interventions to improve cognitive and behavior symptoms in people with dementia: A systematic review and meta‐analysis

Background and Aims

Dementia is becoming a major global public health menace in the aging population affecting 47 million people globally. Dementia has no cure and effective interventions. Treatment of dementia is a big problem. The most common symptomatic medications for cognition, behavior, and global functioning among patients with dementia currently are cholinesterase inhibitors and memantine. However, Information on the effectiveness of cholinesterase inhibitors for dementia is conflicting and controversial. Thus, this makes it difficult for decision‐makers, healthcare providers, patients, and caregivers to decide on the most effective intervention. The current meta‐analysis sought to investigate the efficacy of pharmacologic interventions to improve cognitive and behavioral symptoms in people with living dementia.

Methods

This current systematic review and meta‐analysis used the preferred reporting items for systematic reviews and meta‐analyses to ensure accuracy and comprehensiveness. The Cochrane MEDLINE, Database of Systematic Reviews, and other databases were thoroughly searched for relevant studies. We selected Studies such as randomized controlled trials published in English with a sample size of at least 20 subjects. We selected and applied the random‐effects meta‐analysis as the most preferred model because of the heterogeneity across studies. The computation of the weighted effect size was based on the result from the test of heterogeneity.

Results

Twenty‐two studies were finally used in the meta‐analysis. The study subjects who received donepezil 5 mg/day, donepezil 10 mg/day, and galantamine 24 mg/day had improved cognition symptoms (ADAS‐cog) score of −1.46 (95% CI = −2.24, −0.68, z = 3.67, p < 0.001), −2.31 (95% CI = −3.30, −1.31, z = 5.45, p < 0.001) and −3.04 (95% CI = −4.16, −1.92, z = 5.31, p < 0.001) respectively.

Conclusion

The current meta‐analysis suggests significant benefits of cholinesterase inhibitors such as donepezil (5 and 10 mg/day) and galantamine on cognitive symptoms.

Management of psychiatric and cognitive complications in Parkinson's disease

Neuropsychiatric symptoms (NPSs) such as affective disorders, psychosis, behavioral changes, and cognitive impairment are common in Parkinson's disease (PD). However, NPSs remain under-recognized and under-treated, often leading to adverse outcomes. Their epidemiology, presentation, risk factors, neural substrate, and management strategies are incompletely understood. While psychological and psychosocial factors may contribute, hallmark PD neuropathophysiological changes, plus the associations between exposure to dopaminergic medications and occurrence of some symptoms, suggest a neurobiological basis for many NPSs. A range of psychotropic medications, psychotherapeutic techniques, stimulation therapies, and other non-pharmacological treatments have been studied, are used clinically, and are beneficial for managing NPSs in PD. Appropriate management of NPSs is critical for comprehensive PD care, from recognizing their presentations and timing throughout the disease course, to the incorporation of different therapeutic strategies (ie, pharmacological and non-pharmacological) that utilize a multidisciplinary approach.

Mild cognitive impairment in patients with Parkinson’s disease: An updated mini-review and future outlook

Mild cognitive impairment (MCI) is one of the common non-motor symptoms in patients with Parkinson’s disease (PD). MCI is the transition stage between normal aging and full-blown dementia and is also a powerful predictor of dementia. Although the concept of MCI has been used to describe some of the PD symptoms for many years, there is a lack of consistent diagnostic criteria. Moreover, because of the diverse patterns of the cognitive functions, each cognitive impairment will have a different progression. In this review, we overviewed the diagnostic criteria for PD-MCI, primarily focused on the heterogeneity of PD-MCI patients’ cognitive function, including various types of cognitive functions and their progression rates. A review of this topic is expected to be beneficial for clinical diagnosis, early intervention, and treatment. In addition, we also discussed the unmet needs and future vision in this field.

Effect of donepezil for dementia prevention in Parkinson's disease with severe hyposmia (The DASH-PD study): A randomized long-term placebo-controlled trial

BACKGROUND

Dementia greatly contributes to poor prognosis in patients with Parkinson's disease (PD). We previously reported that severe olfactory dysfunction may be a good predictor of Parkinson's disease dementia (PDD). In this trial, we investigated whether early administration of donepezil to patients with severe hyposmia can reduce the development of PDD.

METHODS

This was a multi-centre, randomized, double-blind, parallel group, placebo-controlled trial in patients with non-demented PD with severe hyposmia (The Donepezil Application for Severe Hyposmic Parkinson's Disease [DASH-PD] study). A total of 201 patients were randomly allocated to receive donepezil or placebo in addition to standard therapy for PD. Patients were followed up every 6 months until the onset of PDD or for a maximum of 4 years. The primary endpoint was the onset of dementia. The secondary endpoint was cognitive impairment measured by Addenbrooke's Cognitive Examination-Revised (ACE-R) and the Clinical Dementia Rating (CDR).(UMIN000009958: February 2013 to May 2019).

FINDINGS

A total of 201 hyposmic patients with PD were randomly assigned to a treatment: 103 to donepezil and 98 to placebo. Overall, 141 (70%) patients completed the 4-year intervention. During follow-up, 7 of 103 (6.8%) patients in the donepezil group and 12 of 98 (12.2%) patients in the placebo group developed PDD; however, the hazard ratio of PDD incidence was not statistically significant (hazard ratio (HR), 0.609; 95% confidence interval, 0.240 to 1.547; p = 0.2969). At week 208, the patients in the donepezil group had better scores on the ACE-R (p < 0.005) and the CDR (p < 0.005) than those taking placebo.

INTERPRETATION

Administration of donepezil to PD patients with severe olfactory dysfunction for 4 years did not change the incidence of dementia but had a beneficial effect on neuropsychological function, with good tolerability.

FUNDING

The Ministry of Health Labour and Welfare and the Japan Agency for Medical Research and Development provided funding for this study.

Validation of the Greek version of the Abbreviated Mental Test Score: Preliminary findings for cognitively impaired patients of different etiology

BACKGROUND

Screening people's cognitive skills have been proven essential for reference to full assessment. These methods include short scales, such as the Abbreviated Mental Test Score (AMTS). The AMTS is a valid 10-item questionnaire that has been translated into many languages, but not in Greek yet. The aim of this study is the validation of the Greek version of the AMTS with an additional estimation of its cutoff scores.

METHODS

About 132 individuals [60 controls and 72 patients (24 with Parkinson's disease (PD), 24 with Parkinson's disease dementia (PDD), and 24 with Alzheimer's disease (AD)] participated in this study. All participants besides the AMTS completed the Mini Mental State Examination (MMSE), the Tuokko's Clock Drawing Test (CDT), the Instrumental Activities of Daily Living (IADL), the Arizona Battery for Communication Disorders of Dementia (ABCD), the Hellenic versions of the Neuropsychiatric Inventory (NPI), and the Geriatric Depression Scale (GDS-15).

RESULTS

Statistically significant differences were found between all subgroups for the AMTS. The AMTS showed high internal consistency (Cronbach alpha = 0.819 and coefficient omega ω = 0.814). A threshold equal to 6.50 (AUC: 0.908, p = 0.000) between groups with and without cognitive impairment was calculated. The AMTS was significantly correlated with the CDT, IADL, and MMSE.

CONCLUSION

The proposed version of the AMTS can distinguish between groups with and without cognitive impairment. Additionally, the AMTS is found to be clinically valid having high reliability and classification accuracy. Conclusively, it is a valuable instrument for screening different types of cognitively impaired patients.

Caring for patients with cognitive dysfunction, fluctuations and dementia caused by Parkinson's disease

Cognitive dysfunction is one of the most prevalent non-motor symptoms in patients with Parkinson's disease (PD). While it tends to worsen in the later stages of disease, it can occur at any time, with 15-20% of patients exhibiting cognitive deficits at diagnosis (Aarsland et al., 2010; Goldman and Sieg, 2020). The characteristic features of cognitive dysfunction include impairment in executive function, visuospatial abilities, and attention, which vary in severity from subtle impairment to overt dementia (Martinez-Horta and Kulisevsky, 2019). To complicate matters, cognitive dysfunction is prone to fluctuate in PD patients, impacting diagnosis and the ability to assess progression and decision-making capacity. The diagnosis of cognitive impairment or dementia has a huge impact on patient independence, quality of life, life expectancy and caregiver burden (Corallo et al., 2017; Lawson et al., 2016; Leroi et al., 2012). It is therefore essential that physicians caring for patients with PD provide education, screening and treatment for this aspect of the disease. In this chapter, we provide a practical guide for the assessment and management of various degrees of cognitive dysfunction in patients with PD by approaching the disease at different stages. We address risk factors for cognitive dysfunction, prevention strategies prior to making the diagnosis, available tools for screening. Lastly, we review aspects of care, management and considerations, including decision-making capacity, that occur after the patient has been diagnosed with cognitive dysfunction or dementia.

Effects of eszopiclone on sleep quality and cognitive function in elderly patients with Alzheimer's disease and sleep disorder: A randomized controlled trial

OBJECTIVE

To investigate the effects of eszopiclone on sleep quality and cognitive function in elderly patients with Alzheimer's disease (AD) and sleep disorders.

METHODS

This study was a prospective study of 96 elderly patients with AD and sleep disturbance treated in our hospital from April 2019 to December 2020. All patients were divided into a control group (48 patients, given alprazolam tablets) and a study group (48 patients, given eszopiclone) according to the random number table method.

RESULTS

After treatment, compared with the control group, the study group had lower sleep latency, daytime function, sleep disturbance, sleep efficiency, sleep quality, sleeping time, and hypnotic medication scores (p < .05). After treatment, sleep progression and sleep architecture improvement were more obvious in the study group compared with the control group (p < .05). After treatment, compared with the control group, the rhythm disturbance, psychotic disorder, hallucination, phobic anxiety, and disorder in the study group improved more significantly (p < .05). After treatment, compared with the control group, the scores of orientation, attention, memory, calculation, recall, and language ability in the study group improved more significantly (p < .05). After treatment, the scores of the physical life self-care scale and instrumental activities of daily living scale in the study group were improved more obviously compared with the control group, with significant differences (p < .05).

CONCLUSION

Eszopiclone can effectively improve the quality of sleep and cognitive function in elderly patients with AD and sleep disorder.

Cholinesterase inhibitors for gait, balance, and fall in Parkinson disease: a meta-analysis

Gait disturbance and imbalance are the major symptoms of Parkinson disease (PD), with fall being the most undesirable consequence. However, few effective evidence-based treatments are available for alleviating these symptoms and preventing falls. Cholinesterase inhibitors (ChEIs) are a well-established treatment for PD dementia with possible impacts on gait, balance, and fall reduction. The present study involved a meta-analysis of randomized controlled trials (RCTs) to investigate the effects of ChEIs on gait, balance, and fall in patients with PD. We searched for studies using the PubMed, Embase, and Web of Science databases. The major outcomes were effects on gait parameters, balance, and fall. This study was registered with PROSPERO (CRD42021254733). Five RCTs were included in the present meta-analysis. ChEIs did not significantly increase gait speed in PD patients (mean difference [MD]: 0.03 m/s, 95% confidence interval [CI]: -0.02 to 0.07, p = 0.29). However, ChEI treatment significantly decreased step or stride variability during the single task (standard MD: -0.43, 95% CI = -0.79 to -0.06, p = 0.02). Regarding fall and balance, trending but nonsignificant beneficial effects were observed with ChEI treatment. In conclusion, although ChEI treatment did not significantly improve gait speed and reduce fall, it can significantly reduce step or stride variability. Considering that gait disorder is a challenging issue in patients with PD and that ChEIs are generally tolerable, the present meta-analysis may provide more evidence for the benefit of ChEIs on PD gait disturbance as an alternative treatment consideration.

Acetylcholinesterase Inhibitors in the Treatment of Neurodegenerative Diseases and the Role of Acetylcholinesterase in their Pathogenesis

Acetylcholinesterase (AChE) plays an important role in the pathogenesis of neurodegenerative diseases by influencing the inflammatory response, apoptosis, oxidative stress and aggregation of pathological proteins. There is a search for new compounds that can prevent the occurrence of neurodegenerative diseases and slow down their course. The aim of this review is to present the role of AChE in the pathomechanism of neurodegenerative diseases. In addition, this review aims to reveal the benefits of using AChE inhibitors to treat these diseases. The selected new AChE inhibitors were also assessed in terms of their potential use in the described disease entities. Designing and searching for new drugs targeting AChE may in the future allow the discovery of therapies that will be effective in the treatment of neurodegenerative diseases.

Parkinson disease-associated cognitive impairment

Parkinson disease (PD) is the second most common neurodegenerative disorder, affecting >1% of the population ≥65 years of age and with a prevalence set to double by 2030. In addition to the defining motor symptoms of PD, multiple non-motor symptoms occur; among them, cognitive impairment is common and can potentially occur at any disease stage. Cognitive decline is usually slow and insidious, but rapid in some cases. Recently, the focus has been on the early cognitive changes, where executive and visuospatial impairments are typical and can be accompanied by memory impairment, increasing the risk for early progression to dementia. Other risk factors for early progression to dementia include visual hallucinations, older age and biomarker changes such as cortical atrophy, as well as Alzheimer-type changes on functional imaging and in cerebrospinal fluid, and slowing and frequency variation on EEG. However, the mechanisms underlying cognitive decline in PD remain largely unclear. Cortical involvement of Lewy body and Alzheimer-type pathologies are key features, but multiple mechanisms are likely involved. Cholinesterase inhibition is the only high-level evidence-based treatment available, but other pharmacological and non-pharmacological strategies are being tested. Challenges include the identification of disease-modifying therapies as well as finding biomarkers to better predict cognitive decline and identify patients at high risk for early and rapid cognitive impairment.

Treatment of Parkinson's Disease with Cognitive Impairment: Current Approaches and Future Directions

Cognitive impairment risk in Parkinson's disease increases with disease progression and poses a significant burden to the patients, their families and society. There are no disease-modifying therapies or preventative measures for Parkinson's disease mild cognitive impairment (PD-MCI), or Parkinson's disease dementia (PDD). This article reviews current and previously investigated treatments and those under investigation, including pharmacologic, non-pharmacologic and surgical procedures. There are currently no effective pharmacologic or non-pharmacologic treatments for PD-MCI. The only recommended treatment for PDD currently is rivastigmine, a cholinesterase inhibitor. Donepezil and galantamine-other cholinesterase inhibitors-are possibly useful. Memantine, a N-methyl-D-aspartate (NMDA) receptor antagonist, is considered investigational in PDD. Drug repurposing (atomoxetine, levodopa, insulin, atomoxetine for PD-MCI; ambroxol and ceftriaxone for PDD) and novel medications (SYN120, GRF6021, NYX-458 for PD-MCI; ANAVEX2-73, LY3154207, ENT-01, DAAOI-P for PDD) currently have insufficient evidence. There is growing research supporting exercise in the treatment of PD-MCI, but most non-pharmacological approaches have insufficient evidence for use in PD-MCI (cognitive rehabilitation, deep brain stimulation, transcranial direct current stimulation, transcranial ultrasound, vestibular nerve stimulation) and PDD (cognitive intervention, deep brain stimulation, transcranial alternating current stimulation, transcranial ultrasound, temporal blood brain barrier disruption). Research is needed for both disease-modifying and symptomatic treatments in PD cognitive impairment.

Mechanistic insights into the pathogenesis of neurodegenerative diseases: towards the development of effective therapy

Neurodegeneration is a prevalent and one of the emerging reasons for morbidity, mortality, and cognitive impairment in aging. Dementia is one of such conditions of neurodegeneration, partially manageable, irreversible, and worsens over time. This review is focused on biological and psychosocial risk factors associated with Alzheimer's and Parkinson's diseases, highlighting the value of cognitive decline. We further emphasized on current therapeutic strategies from pharmacological and non-pharmacological perspectives focusing on their effects on cognitive impairment, protein aggregation, tau pathology, and improving the quality of life. Deeper mechanistic insights into the multifactorial neurodegeneration could offer the design and development of promising diagnostic and therapeutic strategies.

Donepezil for mild cognitive impairment in Parkinson's disease

We investigated the efficacy of donepezil for mild cognitive impairment in Parkinson’s disease (PD-MCI). This was a prospective, non-randomized, open-label, two-arm study. Eighty PD-MCI patients were assigned to either a treatment or control group. The treatment group received donepezil for 48 weeks. The primary outcome measures were the Korean version of Mini-Mental State Exam and Montreal Cognitive Assessment scores. Secondary outcome measures were the Clinical Dementia Rating, Unified Parkinson’s Disease Rating Scale part III, Clinical Global Impression scores. Progression of dementia was assessed at 48-week. Comprehensive neuropsychological tests and electroencephalography (EEG) were performed at baseline and after 48 weeks. The spectral power ratio of the theta to beta2 band (TB2R) in the electroencephalogram was analyzed. There was no significant difference in the primary and secondary outcome measures between the two groups. However, the treatment group showed a significant decrease in TB2R at bilateral frontotemporoparietal channels compared to the control group. Although we could not demonstrate improvements in the cognitive functions, donepezil treatment had a modulatory effect on the EEG in PD-MCI patients. EEG might be a sensitive biomarker for detecting changes in PD-MCI after donepezil treatment.

Non-motor complications in late stage Parkinson's disease: recognition, management and unmet needs

Introduction: The burden of non-motor symptoms (NMS) is a major determinant of health-related quality of life in Parkinson's disease (PD), particularly at its late stage.Areas covered: The late stage is usually defined as the period from unstable advanced to the palliative stage, characterized by a combination of emerging treatment-resistant axial motor symptoms (freezing of gait, postural instability, falls and dysphagia), as well as both non-dopaminergic and dopaminergic NMS: cognitive decline, neuropsychiatric symptoms, aspects of dysautonomia, pain and sleep disturbances (insomnia and excessive day-time sleepiness). Here, the authors summarize the current knowledge on NMS dominating the late stage of PD and propose a pragmatic and clinically focused approach for their recognition and treatment.Expert opinion: The NMS progression pattern is complex and remains under-researched. While dopamine-dependent NMS may improve with dopamine replacement therapy, non-dopamine dependent NMS worsen progressively and culminate at the late stages of PD. Furthermore, some PD specific features could interact negatively with other comorbidities, multiple medication use and frailty - the evaluation of these aspects is important in the creation of personalized management plans in the late stage of PD.

Current Perspectives on the Assessment and Management of Gait Disorders in Parkinson's Disease

Gait dysfunction is a key defining feature of Parkinson's disease (PD), and is associated with symptoms of freezing and an increased risk of falls. In this narrative review, we cover the putative mechanisms of gait dysfunction in PD, the assessment of gait abnormalities, and the management of symptoms caused by the inherent difficulty in walking. Our understanding of the causes of gait problems in PD has progressed in recent times, moving from neurocognitive theory to correlates of affected neuronal pathways. In particular, this can be shown to correspond with abnormalities in responses to dual-task paradigms and dysfunction in cholinergic signaling. Great progress has been made in the sophistication and precision of gait assessment; however, it has firmly remained in the research domain. There is significant momentum behind wearable technologies that can be used by patients in their own environment, acting as digital biomarkers that can not only reflect progression but also independently discriminate PD from non-PD individuals. The treatment of gait dysfunction has historically relied on physical therapies and training combined with a view to mitigating the impact of such consequences as falls. Pharmacological therapies that are the mainstay of treatment in PD have tended to address symptoms like bradykinesia; however, optimization of dopaminergic therapies likely has a positive effect on quality of gait. Other targets have been assessed with the goal of improving gait, of which medications that improve cholinergic signaling appear most promising. Neuromodulation techniques are increasingly used in the form of deep-brain stimulation; however, standard targets, such as the globus pallidus interna, have a modest effect on gait. Considerable benefit has been seen through targeting the pedunculopontine nucleus, and a dual-target approach may be warranted. Stimulation of the spinal cord and brain through direct or magnetic approaches has been assessed, but requires further evidence.

Research on developing drugs for Parkinson's disease

Current treatments for Parkinson's disease (PD) are mainly dopaminergic drugs. However, dopaminergic drugs are only symptomatic treatments and limited by several side effects. Recent studies into drug development focused on emerging new molecular mechanisms, including nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, nuclear receptor-related 1 (Nurr1), adenosine receptor A2, nicotine receptor, metabotropic glutamate receptors (mGluRs), and glucocerebrosidase (GCase). Also, immunotherapy and common pathological mechanisms shared with Alzheimer's Disease (AD) and diabetes have attracted much attention. In this review, we summarized the development of preclinical and clinical studies of novel drugs and the improvement of dopaminergic drugs to provide a prospect for PD treatment.

Treating hallucinations in Parkinson's disease

Introduction: Hallucinations in Parkinson's disease are common, can complicate medication management and significantly impact upon the quality of life of patients and their carers.Areas covered: This review aims to examine current evidence for the management of hallucinations in Parkinson's disease.Expert opinion: Treatment of hallucinations in Parkinson's disease should be both individualized and multifaceted. Screening, education, medication review and the avoidance of common triggers are important. For well-formed visual hallucinations, acetylcholinesterase inhibitors are recommended first-line. Refractory or severe symptoms may require the cautious use of atypical antipsychotics. Antidepressants may be beneficial in the appropriate setting. Unfortunately, current therapies for hallucinations offer only limited benefits and future research efforts are desperately required to improve the management of these challenging symptoms.

Challenges and opportunities for improving the landscape for Lewy body dementia clinical trials

Lewy body dementia (LBD), including dementia with Lewy bodies and Parkinson's disease dementia, affects over a million people in the USA and has a substantial impact on patients, caregivers, and society. Symptomatic treatments for LBD, which can include cognitive, neuropsychiatric, autonomic, sleep, and motor features, are limited with only two drugs (cholinesterase inhibitors) currently approved by regulatory agencies for dementia in LBD. Clinical trials represent a top research priority, but there are many challenges in the development and implementation of trials in LBD. To address these issues and advance the field of clinical trials in the LBDs, the Lewy Body Dementia Association formed an Industry Advisory Council (LBDA IAC), in addition to its Research Center of Excellence program. The LBDA IAC comprises a diverse and collaborative group of experts from academic medical centers, pharmaceutical industries, and the patient advocacy foundation. The inaugural LBDA IAC meeting, held in June 2019, aimed to bring together this group, along with representatives from regulatory agencies, to address the topic of optimizing the landscape of LBD clinical trials. This review highlights the formation of the LBDA IAC, current state of LBD clinical trials, and challenges and opportunities in the field regarding trial design, study populations, diagnostic criteria, and biomarker utilization. Current gaps include a lack of standardized clinical assessment tools and evidence-based management strategies for LBD as well as difficulty and controversy in diagnosing LBD. Challenges in LBD clinical trials include the heterogeneity of LBD pathology and symptomatology, limited understanding of the trajectory of LBD cognitive and core features, absence of LBD-specific outcome measures, and lack of established standardized biologic, imaging, or genetic biomarkers that may inform study design. Demands of study participation (e.g., travel, duration, and frequency of study visits) may also pose challenges and impact trial enrollment, retention, and outcomes. There are opportunities to improve the landscape of LBD clinical trials by harmonizing clinical assessments and biomarkers across cohorts and research studies, developing and validating outcome measures in LBD, engaging the patient community to assess research needs and priorities, and incorporating biomarker and genotype profiling in study design.

Effect of biological treatments on psychotic symptoms in lewy body disease: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

Parkinson disease and dementia with Lewy bodies (collectively termed Lewy body disease) are common neurodegenerative conditions of later life and are frequently associated with distressing psychotic symptoms. The best approach to manage these symptoms is yet to be established and current treatments carry the risk of serious adverse effects.

METHODS

We performed a systematic review and meta-analysis of 19 randomized controlled trials investigating the efficacy of biological treatments for psychotic symptoms in Lewy body disease.

RESULTS

The summary effect estimate did not show a statistically significant benefit of biological treatments for psychotic symptoms in Lewy body disease (SMD -0.48, 95%CI -1.01 to 0.04). This was irrespective of the choice of intervention (SMD -0.53, 95%CI -1.20 to 0.14 for antipsychotic trials) or disease status (SMD -0.59, 95%CI -1.24 to 0.05 for trials of Parkinson disease). There was a significant effect for biological treatments compared with placebo in trials that lasted at least 6 weeks (SMD -0.25, 95%CI -0.43 to -0.08) and those with sample sizes greater than 100 participants (SMD of -0.28 95%CI -0.45 to -0.11).

CONCLUSIONS

In this systematic review and meta-analysis, treatment of psychotic symptoms by biological means did not improve symptoms compared with placebo. Small sample sizes, modest treatment durations, and other methodological differences across the trials do make it difficult to draw firm conclusions. Longer, adequately powered trials utilizing established and novel treatments are needed to provide more definitive evidence to guide clinicians in the best choice of agent to treat these distressing and often persistent symptoms.

Approach to Cognitive Impairment in Parkinson's Disease

Cognitive dysfunction is common in Parkinson's disease (PD) and predicts poor clinical outcomes. It is associated primarily with pathologic involvement of basal forebrain cholinergic and prefrontal dopaminergic systems. Impairments in executive functions, attention, and visuospatial abilities are its hallmark features with eventual involvement of memory and other domains. Subtle symptoms in the premotor and early phases of PD progress to mild cognitive impairment (MCI) which may be present at the time of diagnosis. Eventually, a large majority of PD patients develop dementia with advancing age and longer disease duration, which is usually accompanied by immobility, hallucinations/psychosis, and dysautonomia. Dopaminergic medications and deep brain stimulation help motor dysfunction, but may have potential cognitive side effects. Central acetylcholinesterase inhibitors, and possibly memantine, provide modest and temporary symptomatic relief for dementia, although there is no evidence-based treatment for MCI. There is no proven disease-modifying treatment for cognitive impairment in PD. The symptomatic and disease-modifying role of physical exercise, cognitive training, and neuromodulation on cognitive impairment in PD is under investigation. Multidisciplinary approaches to cognitive impairment with effective treatment of comorbidities, proper rehabilitation, and maintenance of good support systems in addition to pharmaceutical treatment may improve the quality of life of the patients and caregivers.

Minority Enrollment in Parkinson's Disease Clinical Trials: Meta-Analysis and Systematic Review of Studies Evaluating Treatment of Neuropsychiatric Symptoms

BACKGROUND

Randomized clinical trials (RCTs) in Parkinson's disease (PD) have historically enrolled a low number of underrepresented minorities, lessening the generalizability of therapeutic developments. Although there are racial disparities in PD, little is known regarding neuropsychiatric symptoms and other nonmotor manifestations across all races/ethnicities.

OBJECTIVE

To assess minority participation in PD trials evaluating the treatment of neuropsychiatric symptoms and explore underlying reasons.

METHODS

We systematically searched PubMed and Embase for RCTs with a primary goal of treating neuropsychiatric symptoms in PD patients from 2000-2019. The pooled prevalence and 95% confidence interval (CI) of being white and enrolled in a clinical trial was calculated using the inverse variance method. I-square was calculated as a measure of heterogeneity and meta-regression was used to evaluate temporal trends.

RESULTS

We included 63 RCTs with a total of 7,973 patients. In pooled analysis, 11 (17.5%) RCTs reported race/ethnicity. Of studies reporting this data, 5 African American (0.2%), 16 Hispanics (0.64%), and 539 Asians (21.44%) were enrolled. The pooled prevalence of being white in clinical trials was 98% (CI 0.97-0.98, p < 0.001), with 1,908 patients (75.8%). NIH-funded studies were most likely to report racial data when compared to non-NIH trials (p = 0.032).

CONCLUSION

This large pooled analysis found a small percentage of RCTs reporting race/ethnicity when evaluating treatment of neuropsychiatric symptoms in PD. There was a disproportionally high number of white patients when compared to African Americans and Hispanics. More studies are needed to investigate this discrepancy and improve rates of & minority enrollment in PD trials.

T-495, a novel low cooperative M1 receptor positive allosteric modulator, improves memory deficits associated with cholinergic dysfunction and is characterized by low gastrointestinal side effect risk

M₁ muscarinic acetylcholine receptor (M₁ R) activation can be a new therapeutic approach for the treatment of cognitive deficits associated with cholinergic hypofunction. However, M₁ R activation causes gastrointestinal (GI) side effects in animals. We previously found that an M₁ R positive allosteric modulator (PAM) with lower cooperativity (α-value) has a limited impact on ileum contraction and can produce a wider margin between cognitive improvement and GI side effects. In fact, TAK-071, a novel M₁ R PAM with low cooperativity (α-value of 199), improved scopolamine-induced cognitive deficits with a wider margin against GI side effects than a high cooperative M₁ R PAM, T-662 (α-value of 1786), in rats. Here, we describe the pharmacological characteristics of a novel low cooperative M₁ R PAM T-495 (α-value of 170), using the clinically tested higher cooperative M₁ R PAM MK-7622 (α-value of 511) as a control. In rats, T-495 caused diarrhea at a 100-fold higher dose than that required for the improvement of scopolamine-induced memory deficits. Contrastingly, MK-7622 showed memory improvement and induction of diarrhea at an equal dose. Combination of T-495, but not of MK-7622, and donepezil at each sub-effective dose improved scopolamine-induced memory deficits. Additionally, in mice with reduced acetylcholine levels in the forebrain via overexpression of A53T α-synuclein (ie, a mouse model of dementia with Lewy bodies and Parkinson's disease with dementia), T-495, like donepezil, reversed the memory deficits in the contextual fear conditioning test and Y-maze task. Thus, low cooperative M₁ R PAMs are promising agents for the treatment of memory deficits associated with cholinergic dysfunction.

Use of Cholinesterase Inhibitors in Non-Alzheimer's Dementias

Non-Alzheimer's dementias constitute 30% of all dementias and present with major cognitive and behavioral disturbances. Cholinesterase inhibitors improve memory by increasing brain acetylcholine levels and are approved symptomatic therapies for Alzheimer's disease (AD). They have also been investigated in other types of dementias with potential cholinergic dysfunction. There is compelling evidence for a profound cholinergic deficit in Lewy Body dementia (LBD) and Parkinson's disease dementia (PDD), even to a greater extent than AD. However, this deficit is difficult to objectivize in vascular dementia (VaD) given the increased comorbidity with AD. Furthermore, there is minimal to no evidence for cholinergic loss in frontotemporal dementia (FTD). Although cholinesterase inhibitors showed significant improvement in cognitive, behavioral, and functional measures in both LBD and PDD clinical trials, only rivastigmine is approved for PDD, due to the heterogeneity of the scales used, the duration of trials, and the limited sample sizes impacting data interpretation. Similarly, the interpretation of findings in VaD trials are limited by the lack of pre-defined inclusion criteria for 'pure VaD' and the wide heterogeneity of patients enrolled with respect to location and extent of cerebrovascular disease. In FTD patients, cholinesterase inhibitors were mostly associated with worsening of cognitive and behavioral symptoms. In non-AD dementias, cholinesterase inhibitors were well tolerated, with increased reports of mild to moderate cholinergic side effects and a non-significant trend for increased cardio and cerebrovascular events with rivastigmine in VaD, justifying their cautious use on a case-by-case basis, especially when there is evidence for cholinergic deficit.

Deep brain stimulation for dementias

OBJECTIVE The aim of this article is to review the authors' and published experience with deep brain stimulation (DBS) therapy for the treatment of patients with Alzheimer's disease (AD) and Parkinson's disease dementia (PDD). METHODS Two targets are current topics of investigation in the treatment of AD and PDD, the fornix and the nucleus basalis of Meynert. The authors reviewed the current published clinical experience with attention to patient selection, biological rationale of therapy, anatomical targeting, and clinical results and adverse events. RESULTS A total of 7 clinical studies treating 57 AD patients and 7 PDD patients have been reported. Serious adverse events were reported in 6 (9%) patients; none resulted in death or disability. Most studies were case reports or Phase 1/2 investigations and were not designed to assess treatment efficacy. Isolated patient experiences demonstrating improved clinical response after DBS have been reported, but no significant or consistent cognitive benefits associated with DBS treatment could be identified across larger patient populations. CONCLUSIONS PDD and AD are complex clinical entities, with investigation of DBS intervention still in an early phase. Recently published studies demonstrate acceptable surgical safety. For future studies to have adequate power to detect meaningful clinical changes, further refinement is needed in patient selection, metrics of clinical response, and optimal stimulation parameters.

Rebalancing metal dyshomeostasis for Alzheimer's disease therapy

Alzheimer's disease (AD) is a type of neurodegenerative malady that is associated with the accumulation of amyloid plaques. Metal ions are critical for the development and upkeep of brain activity, but metal dyshomeostasis can contribute to the development of neurodegenerative diseases, including AD. This review highlights the association between metal dyshomeostasis and AD pathology, the feasibility of rebalancing metal homeostasis as a therapeutic strategy for AD, and a survey of current drugs that action via rebalancing metal homeostasis. Finally, we discuss the challenges that should be overcome by researchers in the future to enable the practical use of metal homeostasis rebalancing agents for clinical application.

The Neuropsychiatry of Parkinson Disease: A Perfect Storm

Affective disorders, cognitive decline, and psychosis have long been recognized as common in Parkinson disease (PD), and other psychiatric disorders include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their frequent occurrence, there is incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically multimorbid, and there is great intra- and interindividual variability in presentation. The hallmark neuropathophysiological changes that occur in PD, plus the association between exposure to dopaminergic medications and certain psychiatric disorders, suggest a neurobiological basis for many psychiatric symptoms, although psychological factors are involved as well. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated and although psychotropic medication use is common, controlled studies demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors and establishing efficacious and well-tolerated treatment strategies.

Current treatment of behavioral and cognitive symptoms of Parkinson's disease

Cognitive and behavioral symptoms are common in Parkinson's disease, may occur even in the prodromal stages of the disease, worsen with disease progression, and surpass motor symptoms as the major factors affecting patient quality of life and caregiver burden. The symptoms may be caused by the disease pathology or they may represent adverse effects of treatment, or both etiological factors may contribute. Although many of these symptoms are related to dopaminergic dysfunction or dopaminergic medication, other neurotransmitters are involved as well. Behavioral symptoms including impulse control disorders, apathy, psychosis, as well as mild cognitive impairment and dementia are reviewed with a special focus on current treatment approaches.

Ambroxol as a novel disease-modifying treatment for Parkinson's disease dementia: protocol for a single-centre, randomized, double-blind, placebo-controlled trial

BACKGROUND

Currently there are no disease-modifying treatments for Parkinson's disease dementia (PDD), a condition linked to aggregation of the protein α-synuclein in subcortical and cortical brain areas. One of the leading genetic risk factors for Parkinson's disease is being a carrier in the gene for β-Glucocerebrosidase (GCase; gene name GBA1). Studies in cell culture and animal models have shown that raising the levels of GCase can decrease levels of α-synuclein. Ambroxol is a pharmacological chaperone for GCase and is able to raise the levels of GCase and could therefore be a disease-modifying treatment for PDD. The aims of this trial are to determine if Ambroxol is safe and well-tolerated by individuals with PDD and if Ambroxol affects cognitive, biochemical, and neuroimaging measures.

METHODS

This is a phase II, single-centre, double-blind, randomized placebo-controlled trial involving 75 individuals with mild to moderate PDD. Participants will be randomized into Ambroxol high-dose (1050 mg/day), low-dose (525 mg/day), or placebo treatment arms. Assessments will be undertaken at baseline, 6-months, and 12-months follow up times. Primary outcome measures will be the Alzheimer's disease Assessment Scale-cognitive subscale (ADAS-Cog) and the ADCS Clinician's Global Impression of Change (CGIC). Secondary measures will include the Parkinson's disease Cognitive Rating Scale, Clinical Dementia Rating, Trail Making Test, Stroop Test, Unified Parkinson's disease Rating Scale, Purdue Pegboard, Timed Up and Go, and gait kinematics. Markers of neurodegeneration will include MRI and CSF measures. Pharmacokinetics and pharmacodynamics of Ambroxol will be examined through plasma levels during dose titration phase and evaluation of GCase activity in lymphocytes.

DISCUSSION

If found effective and safe, Ambroxol will be one of the first disease-modifying treatments for PDD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02914366, 26 Sep 2016/retrospectively registered.

Available and future treatments for atypical parkinsonism. A systematic review

AIMS

Success in treating patients with atypical parkinsonian syndromes, namely progressive supranuclear palsy (PSP), cortico-basal degeneration (CBD), multiple system atrophy (MSA), Parkinson's disease with dementia (PDD), and Lewy body dementia with (LBD), remains exceedingly low. The present work overviews the most influential research literature collected on MEDLINE, ISI Web of Science, Cochrane Library, and Scopus for available treatment in atypical parkinsonisms without time restriction.

DISCUSSION

Transdermal rotigotine, autologous mesenchymal stem cells, tideglusib, and coenzyme Q10 along with donepezil, rivastigmine, memantine, and the deep brain stimulation have shown some benefits in alleviating symptoms in APS. Moreover, many new clinical trials are ongoing testing microtubule stabilizer, antitau monoclonal antibody, tau acetylation inhibition, cell replacement, selective serotonin reuptake inhibitor, active immunization, inhibition of toxic α-synuclein oligomers formation, and inhibition of microglia.

CONCLUSION

A detailed knowledge of the pathological mechanism underlying the disorders is needed, and disease-modifying therapies are required to offer better therapeutic options to physician and caregivers of APS patients.

Update on treatments for nonmotor symptoms of Parkinson's disease-an evidence-based medicine review

OBJECTIVE

To update evidence-based medicine recommendations for treating nonmotor symptoms in Parkinson's disease (PD).

BACKGROUND

The International Parkinson and Movement Disorder Society Evidence-Based Medicine Committee's recommendations for treatments of PD were first published in 2002, updated in 2011, and now updated again through December 31, 2016.

METHODS

Level I studies testing pharmacological, surgical, or nonpharmacological interventions for the treatment of nonmotor symptoms in PD were reviewed. Criteria for inclusion and quality scoring were as previously reported. The disorders covered were a range of neuropsychiatric symptoms, autonomic dysfunction, disorders of sleep and wakefulness, pain, fatigue, impaired olfaction, and ophthalmologic dysfunction. Clinical efficacy, implications for clinical practice, and safety conclusions are reported.

RESULTS

A total of 37 new studies qualified for review. There were no randomized controlled trials that met inclusion criteria for the treatment of anxiety disorders, rapid eye movement sleep behavior disorder, excessive sweating, impaired olfaction, or ophthalmologic dysfunction. We identified clinically useful or possibly useful interventions for the treatment of depression, apathy, impulse control and related disorders, dementia, psychosis, insomnia, daytime sleepiness, drooling, orthostatic hypotension, gastrointestinal dysfunction, urinary dysfunction, erectile dysfunction, fatigue, and pain. There were no clinically useful interventions identified to treat non-dementia-level cognitive impairment.

CONCLUSIONS

The evidence base for treating a range of nonmotor symptoms in PD has grown substantially in recent years. However, treatment options overall remain limited given the high prevalence and adverse impact of these disorders, so the development and testing of new treatments for nonmotor symptoms in PD remains a top priority. © 2019 International Parkinson and Movement Disorder Society.

Novel Treatment Opportunities Against Cognitive Impairment in Parkinson's Disease with an Emphasis on Diabetes-Related Pathways

Cognitive impairment is highly prevalent in patients with Parkinson's disease (PD) and causes adverse health outcomes. Novel procognitive therapies are needed to address this unmet need. It is now established that there is an increased risk of dementia in patients with type 2 diabetes mellitus (T2DM) and, moreover, T2DM and PD may have common underlying biological mechanisms. As such, T2DM medications are emerging as potential therapies in the context of PD dementia (PDD). In this review, we provide an update on pathophysiological mechanisms underlying cognitive impairments and PDD, focusing on diabetes-related pathways. Finally, we have conducted a review of ongoing clinical trials in PD patients with dementia, highlighting the multiple pharmacological mechanisms that are targeted to achieve cognitive enhancement.