A general clinical overview of the non-motor symptoms in Parkinson's disease: Neuropsychiatric symptoms.

The heterogeneity of non-motor features observed in people with Parkinson's disease (PD) is often dominated by one or more symptoms belonging to the neuropsychiatric spectrum, such as cognitive impairment, psychosis, depression, anxiety, and apathy. Due to their high prevalence in people with PD (PwP) and their occurrence in every stage of the disease, from the prodromal to the advanced stage, it is not surprising that PD can be conceptualised as a complex neuropsychiatric disorder. Despite progress in understanding the pathophysiological mechanisms underlying the neuropsychiatric signs and symptoms in PD, and better identification and diagnosis of these symptoms, effective treatments are still a major unmet need. The impact of these symptoms on the quality of life of PwP and caregivers, as well as their contribution to the overall non-motor symptom burden can be greater than that of motor symptoms and require a personalised, holistic approach. In this chapter, we provide a general clinical overview of the major neuropsychiatric symptoms of PD.

Nutrient Intake and Its Association with Appendicular Total Lean Mass and Muscle Function and Strength in Older Adults: A Population-Based Study.

Treatment options for sarcopenia are currently limited, and primarily rely on two main therapeutic approaches: resistance-based physical activity and dietary interventions. However, details about specific nutrients in the diet or supplementation are unclear. We aim to investigate the relationship between nutrient intake and lean mass, function, and strength. Data were derived from the Gothenburg H70 birth cohort study in Sweden, including 719,70-year-olds born in 1944 (54.1% females). For independent variables, the diet history method (face-to-face interviews) was used to estimate habitual food intake during the preceding three months. Dependent variables were gait speed (muscle performance), hand grip strength (muscle strength), and the appendicular lean soft tissue index (ALSTI). Linear regression analyses were performed to analyze the relationship between the dependent variables and each of the covariates. Several nutrients were positively associated with ALSTI, such as polyunsaturated fatty acids (DHA, EPA), selenium, zinc, riboflavin, niacin equivalent, vitamin B12, vitamin D, iron, and protein. After correction for multiple comparisons, there were no remaining correlations with handgrip and gait speed. Findings of positive correlations for some nutrients with lean mass suggest a role for these nutrients in maintaining muscle volume. These results can be used to inform clinical trials to expand the preventive strategies and treatment options for individuals at risk of muscle loss and sarcopenia.

An analysis of omega-3 clinical trials and a call for personalized supplementation for dementia prevention.

INTRODUCTION: Targeted interventions are needed to delay or prevent the onset of neurodegenerative diseases. Poor dietary habits are associated with cognitive decline, highlighting the benefits of a healthy diet with fish and polyunsaturated fatty acids (PUFAs). Intake of omega-3 PUFAs docosahexaenoic acid (DHA), α-linolenic acid (ALA) and eicosapentaenoic acid (EPA) is linked with healthy aging, cardiovascular benefits, and reduced risk of Alzheimer's disease. Although omega-3 has health benefits, its intake is often inadequate and insufficient in modern diets. Although fish oil supplements offer an alternative source, inconsistent results from clinical trials raise questions about the factors determining their success. AREAS COVERED: In this this review, the authors discuss the aforementioned determining factors and highlight strategies that could enhance the effectiveness of omega-3 PUFAs interventions for dementia and cognitive decline. Moreover, the authors provide suggestions for potential future research. EXPERT OPINION: Factors such as diet, lifestyle, and genetic predisposition can all influence the effectiveness of omega-3 supplementation. When implementing clinical trials, it is crucial to consider these factors and recognize their potential impact on the interpretation of results. It is important to study each variable independently and the interactions between them.

Nonmotor symptom burden grading as predictor of cognitive impairment in Parkinson's disease.

BACKGROUND: Identifying predictors of incident cognitive impairment (CI), one of the most problematic long-term outcomes, in Parkinson's disease (PD) is highly relevant for personalized medicine and prognostic counseling. The Nonmotor Symptoms Scale (NMSS) provides a global clinical assessment of a range of NMS, reflecting NMS burden (NMSB), and thus may assist in the identification of an "at-risk" CI group based on overall NMSB cutoff scores. METHODS: To investigate whether specific patterns of PD NMS profiles predict incident CI, we performed a retrospective longitudinal study on a convenience sample of 541 nondemented PD patients taking part in the Nonmotor Longitudinal International Study (NILS) cohort, with Mini-Mental State Examination (MMSE), NMSS, and Scales for Outcomes in PD Motor Scale (SCOPA Motor) scores at baseline and last follow-up (mean 3.2 years) being available. RESULTS: PD patients with incident CI (i.e., MMSE score ≤ 25) at last follow-up (n = 107) had severe overall NMSB level, significantly worse NMSS hallucinations/perceptual problems and higher NMSS attention/memory scores at baseline. Patients with CI also were older and with more advanced disease, but with no differences in disease duration, dopamine replacement therapy, sex, and comorbid depression, anxiety, and sleep disorders. CONCLUSIONS: Our findings suggest that a comprehensive baseline measure of NMS and in particular hallucinations and perceptual problems assessed with a validated single instrument can be used to predict incident CI in PD. This approach provides a simple, holistic strategy to predict future CI in this population.

Depression and synaptic zinc regulation in Alzheimer disease, dementia with lewy bodies, and Parkinson disease dementia.

OBJECTIVE: Depression is a common symptom in dementia with Lewy bodies (DLB), Parkinson disease dementia (PDD), and Alzheimer disease (AD), yet its molecular basis remains unclear and current antidepressants do not appear to be effective. Cerebral zinc has been implicated in depression and synaptic dysfunction. We investigated the relationship between synaptic zinc regulation (for which zinc transporter 3 [ZnT3] is responsible) and depression in a large clinicopathologic study. METHODS: We examined brains from people with PDD (N = 29), DLB (N = 27), and AD (N = 15) and comparison subjects without depression or dementia (N = 24). Individuals were categorized according to the presence and severity of depression (on a scale of 0-3) based on standardized assessments during life (principally Neuropsychiatric Inventory). Western blotting was used to determine ZnT3 levels in Brodmann area 9 (BA9), and regression analysis was used to determine the relationship between ZnT3 and depression. RESULTS: Reductions in ZnT3 in BA9 were significantly associated with elevated depression scores in the study cohort (ß = -0.351, df = 93, t = -3.318 p = 0.0004). This association remained when only individuals with DLB, PDD, and no dementia or depression were examined (ß = -0.347, df = 78, t = -3.271, p = 0.002) or only individuals with AD and no dementia or depression were examined (ß = -0.433, df = 37, t = -2.924, p = 0.006). CONCLUSION: Although decreased zinc levels have been implicated in the genesis of depression in animal models and in major depressive disorder in humans, this study provides the first evidence of a role for zinc in depression in people with dementia and highlights zinc metabolism as a therapeutic target.

Disturbance of automatic auditory change detection in dementia associated with Parkinson's disease: A mismatch negativity study.

OBJECTIVE: To investigate whether automatic auditory change detection, as measured by the mismatch negativity (MMN) event-related potential waveform, differs in dementia associated with Parkinson's disease (PDD) and dementia with Lewy-bodies (DLB) as compared to Alzheimer's disease (AD), Parkinson's disease without dementia (PD) and healthy control subjects (HC). METHOD: Seventeen DLB, 15 PDD, 16 PD, 16 AD patients and 18 HC subjects participated. A passive MMN event-related potential paradigm and an oddball-distractor reaction time paradigm were presented. RESULTS: The PDD patients had reduced MMN area and amplitude compared to the DLB, PD, and the HC groups. The MMN area correlated significantly with number of missed target stimuli in the oddball-distractor task, and the PDD group missed targets significantly more often than the DLB group. CONCLUSION: The results indicate that PDD patients to a larger degree than patients with DLB have a deficit of automatic auditory change detection that contributes to impairment in their ability to selectively attend and respond to deviant auditory stimuli.

Lewy body disease: thalamic cholinergic activity related to dementia and parkinsonism.

Within the spectrum of Lewy body disease cognitive impairment occurs in PD with dementia (PDD) and dementia with Lewy bodies (DLB). Although neocortical cholinergic deficits are associated with cognitive impairments in PDD and DLB, no neurochemical study has been published describing the thalamic cholinergic activity whereas the thalamus plays a major role in modulating cortical activity. Choline acetyltransferase (ChAT) activity was analyzed in reticular (Re), mediodorsal (MD) and centromedian (CM) thalamic nuclei in series of nine controls, five DLB with parkinsonism (DLB + P), five DLB without parkinsonism (DLB - P), six PD without dementia and 14 PDD cases. Significant reductions in ChAT were apparent in PDD as follows: in Re and MD nuclei compared with controls; in MD and CM nuclei compared with DLB + P; and in MD compared with PD. Increased ChAT activity was found in CM nuclei in DLB + P compared with DLB - P. These findings show that significant thalamic presynaptic cholinergic deficits occur only in cases of combined cortical and subcortical neurodegeneration in which dementia developed after prolonged parkinsonism.

Improvement in behavioral symptoms and advance of activity acrophase after short-term bright light treatment in severe dementia.

Ten elderly subjects with severe dementia were given bright light (5000-8000 lux) for 45 min each morning for 4 weeks. Two rating scales of behavioral symptoms in dementia were used as outcome measures: Cohen-Mansfield Agitation Inventory (CMAI) and Behavior Pathology In Alzheimer's Disease Rating Scale (BEHAVE-AD), a scale for sleep-wake disturbances, and actigraphy to monitor activity rhythm. Behavioral symptoms improved with treatment. No changes in sleep-wake measures were found. There was an advance of the activity rhythm acrophase during treatment. These results suggest that short-time bright light improves behavioral symptoms and aspects of activity rhythm disturbances even in severely demented subjects.