Olfaction, dyskinesia and profile of weight change in Parkinson's disease: Identifying neurodegenerative phenotypes

Unravelling the mechanisms of underweight in Parkinson's disease by investigating into the role of gut microbiome

Approximately half of patients with Parkinson's disease (PD) suffer from unintentional weight loss and are underweight, complicating the clinical course of PD patients. Gut microbiota alteration has been proven to be associated with PD, and recent studies have shown that gut microbiota could lead to muscle wasting, implying a possible role of gut microbiota in underweight PD. In this study, we aimed to (1) investigate the mechanism underlying underweight in PD patients with respect to gut microbiota and (2) estimate the extent to which gut microbiota may mediate PD-related underweight through mediation analysis. The data were adapted from Hill-Burns et al., in which 330 participants (199 PD, 131 controls) were enrolled in the study. Fecal samples were collected from participants for microbiome analysis. 16S rRNA gene sequence data were processed using DADA2. Mediation analysis was performed to quantify the effect of intestinal microbial alteration on the causal effect of PD on underweight and to identify the key bacteria that significantly mediated PD-related underweight. The results showed that the PD group had significantly more underweight patients (body mass index (BMI) < 18.5) after controlling for age and sex. Ten genera and four species were significantly different in relative abundance between the underweight and non-underweight individuals in the PD group. Mediation analysis showed that 42.29% and 37.91% of the effect of PD on underweight was mediated through intestinal microbial alterations at the genus and species levels, respectively. Five genera (Agathobacter, Eisenbergiella, Fusicatenibacter, Roseburia, Ruminococcaceae_UCG_013) showed significant mediation effects. In conclusion, we found that up to 42.29% of underweight PD cases are mediated by gut microbiota, with increased pro-inflammatory bacteria and decreased SCFA-producing bacteria, which indicates that the pro-inflammatory state, disturbance of metabolism, and interference of appetite regulation may be involved in the mechanism of underweight PD.

The evaluation of the nutritional status in Parkinson's disease: geriatric nutritional risk index comparison with mini nutritional assessment questionnaire

OBJECTIVE

The symptoms associated with Parkinson's disease may lead to reduced food consumption and in turn, malnutrition. It is therefore important to apply a reliable nutrition screening tool to evaluate the nutritional status of individuals with Parkinson's disease. This cross-sectional study aims to compare the Mini Nutritional Assessment (MNA) questionnaire and the Geriatric Nutrition Risk Index (GNRI) in the assessment of the nutritional status of individuals with Parkinson's disease, and to evaluate the usability of the GNRI in cases of Parkinson's disease.

METHODS

The study was conducted with 89 individuals over the age of 60 who were diagnosed with Parkinson's disease. Study data were collected using a questionnaire form administered through face-to-face interviews, the MNA-Long Form (MNA-LF), and the GNRI was calculated.

RESULTS

The mean GNRI scores were significantly lower in the participants with malnutrition (106.5 ± 19.4) than in the participants at risk of malnutrition (121.0 ± 10.3) and the participants with no malnutrition (125.3 ± 9.6) according to the MNA-LF (p < 0.001). Although there was a positive correlation between the MNA-LF and the GNRI scores, this correlation was not significant (p = 0.095).

CONCLUSIONS

This is the first study to research the nutritional status of individuals with Parkinson's disease using the GNRI. The malnutrition rate detected by GNRI was found to be lower than MNA in Parkinson's patients receiving outpatient treatment. Similar studies are recommended to determine the usability of GNRI on inpatients.

The role of gut-brain axis in a rotenone-induced rat model of Parkinson's disease

Parkinson's disease (PD) is a widespread neurodegenerative condition affecting millions globally. This investigation centered on the gut-brain axis in a rotenone-induced PD rat model. Researchers monitored behavioral shifts, histological modifications, neurodegeneration, and inflammation markers throughout the rats' bodies. Results revealed that rotenone-treated rats displayed reduced exploration (p = 0.004) and motor coordination (p < 0.001), accompanied by decreased Nissl staining and increased alpha-synuclein immunoreactivity in the striatum (p = 0.009). Additionally, these rats exhibited weight loss (T3, mean = 291.9 ± 23.67; T19, mean = 317.5 ± 17.53; p < 0.05) and substantial intestinal histological alterations, such as shortened villi, crypt architecture loss, and inflammation. In various regions, researchers noted elevated immunoreactivity to ionized binding adapter molecule (IBA)-1 (p < 0.05) and reduced immunoreactivity to glial fibrillary acidic protein (p < 0.05) and S100B (p < 0.001), indicating altered glial cell activity. Overall, these findings imply that PD is influenced by gut-brain axis changes and may originate in the intestine, impacting bidirectional gut-brain communication.

Clinical trajectories and biomarkers for weight variability in early Parkinson's disease

Unexplained weight changes that occur in Parkinson's disease (PD), are often neglected and remain a poorly understood non-motor feature in patients with PD. A specific 'Park-weight' phenotype with low body weight has been described, and our aim was to evaluate the clinical and prognostic trajectories and biomarkers of weight variability in PD. We evaluated body weight-related biomarkers in 405 de novo PD patients and 187 healthy controls (HC) over a 5-year follow-up period from the PPMI database. Body-weight variability was defined as intra-individual variability in body weight between visits. PD patients were categorized as weight losers, gainers, or patients with stable weight. The differential progression of motor and non-motor clinical variables between groups was explored using linear mixed-effects models. Finally, we estimated longitudinal changes in weight as a function of baseline and longitudinal striatal presynaptic dopaminergic transporter imaging. PD patients presented a greater weight variability compared to HC (p = 0.003). Patients who developed weight loss had lower CSF amyloid-beta 1-42 (p = 0.009) at baseline. In addition, patients with weight loss showed a faster cognitive decline (p = 0.001), whereas patients with weight gain showed a slower motor progression (p = 0.001), compared to patients with stable weight. Baseline right striatal denervation was a predictor of weight variability in both PD patients and HC (p < 0.001). Similarly, weight variability in PD patients was associated with the progression of right striatal denervation (p < 0.001). Weight variability and specifically weight loss are more frequent in PD compared to HC, and are associated with specific motor, non-motor and cognitive progression patterns. A greater CSF amyloid burden was present at baseline in patients with subsequent weight loss. Presynaptic dopaminergic imaging in the right striatum may serve as a predictor of future weight changes in PD and HC.

Parkinson's disease: the nutrition perspective

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease and affects about 1% of the population over the age of 60 years in industrialised countries. The aim of this review is to examine nutrition in PD across three domains: dietary intake and the development of PD; whole body metabolism in PD and the effects of PD symptoms and treatment on nutritional status. In most cases, PD is believed to be caused by a combination of genetic and environmental factors and although there has been much research in the area, evidence suggests that poor dietary intake is not a risk factor for the development of PD. The evidence about body weight changes in both the prodromal and symptomatic phases of PD is inconclusive and is confounded by many factors. Malnutrition in PD has been documented as has sarcopaenia, although the prevalence of the latter remains uncertain due to a lack of consensus in the definition of sarcopaenia. PD symptoms, including those which are gastrointestinal and non-gastrointestinal, are known to adversely affect nutritional status. Similarly, PD treatments can cause nausea, vomiting and constipation, all of which can adversely affect nutritional status. Given that the prevalence of PD will increase as the population ages, it is important to understand the interplay between PD, comorbidities and nutritional status. Further research may contribute to the development of interventional strategies to improve symptoms, augment care and importantly, enhance the quality of life for patients living with this complex neurodegenerative disease.

The Interactions between Adipose Tissue Secretions and Parkinson's disease; The Role of Leptin

Leptin is a hormone that regulates appetite by acting on receptors in the hypothalamus, where it modifies food intake to maintain equilibrium with the body energy resources. Leptin and its receptors are widely distributed in the central nervous system, suggesting that they may give neuronal survival signals. The potential of leptin to decrease/increase neuronal damage and neuronal plasticity in Parkinson's diseases (PD) is the subject of this review, which outlines our current knowledge of how leptin acts in the brain. Although leptin-mediated neuroprotective signaling results in neuronal death prevention, it can affect neuroinflammatory cascades and also neuronal plasticity which contribute to PD pathology. Other neuroprotective molecules, such as insulin and erythropoietin, share leptin-related signaling cascades, and therefore constitute a component of the neurotrophic effects mediated by endogenous hormones. With the evidence that leptin dysregulation causes increased neuronal vulnerability to damage in PD, using leptin as a target for therapeutic modification is an appealing and realistic option.

The Thermodynamic Consequences of Parkinson's Disease

Several lines of evidence point to a pervasive disturbance of energy balance in Parkinson's disease (PD). Weight loss, common and multifactorial, is the most observable sign of this. Bradykinesia may be best understood as an underinvestment of energy in voluntary movement. This accords with rodent experiments that emphasise the importance of dopamine in allocating motor energy expenditure. Oxygen consumption studies in PD suggest that, when activities are standardised for work performed, these inappropriate energy thrift settings are actually wasteful. That the dopaminergic deficit of PD creates a problem with energy efficiency highlights the role played by the basal ganglia, and by dopamine, in thermodynamic governance. This involves more than balancing energy, since living things maintain their internal order by controlling transformations of energy, resisting probabilistic trends to more random states. This review will also look at recent research in PD on the analysis of entropy-an information theory metric of predictability in a message-in recordings from the basal ganglia. Close relationships between energy and information converge around the concept of entropy. This is especially relevant to the motor system, which regulates energy exchange with the outside world through its flow of information. The malignant syndrome in PD, a counterpart of neuroleptic malignant syndrome, demonstrates how much thermodynamic disruption can result from breakdown of motor signalling in an extreme hypodopaminergic state. The macroenergetic disturbances of PD are consistent with a unifying hypothesis of dopamine's neurotransmitter actions-to adapt energy expenditure to prevailing economic circumstances.

Na+ leak-current channel (NALCN) at the junction of motor and neuropsychiatric symptoms in Parkinson's disease

Parkinson's disease (PD) is a debilitating movement disorder often accompanied by neuropsychiatric symptoms that stem from the loss of dopaminergic function in the basal ganglia and altered neurotransmission more generally. Akinesia, postural instability, tremors and frozen gait constitute the major motor disturbances, whereas neuropsychiatric symptoms include altered circadian rhythms, disordered sleep, depression, psychosis and cognitive impairment. Evidence is emerging that the motor and neuropsychiatric symptoms may share etiologic factors. Calcium/ion channels (CACNA1C, NALCN), synaptic proteins (SYNJ1) and neuronal RNA-binding proteins (RBFOX1) are among the risk genes that are common to PD and various psychiatric disorders. The Na⁺ leak-current channel (NALCN) is the focus of this review because it has been implicated in dystonia, regulation of movement, cognitive impairment, sleep and circadian rhythms. It regulates the resting membrane potential in neurons, mediates pace-making activity, participates in synaptic vesicle recycling and is functionally co-localized to the endoplasmic reticulum (ER)-several of the major processes adversely affected in PD. Here, we summarize the literature on mechanisms and pathways that connect the motor and neuropsychiatric symptoms of PD with a focus on recurring relationships to the NALCN. It is hoped that the various connections outlined here will stimulate further discussion, suggest additional areas for exploration and ultimately inspire novel treatment strategies.

Lower Energy Intake among Advanced vs. Early Parkinson's Disease Patients and Healthy Controls in a Clinical Lunch Setting: A Cross-Sectional Study

Unintentional weight loss has been observed among Parkinson's disease (PD) patients. Changes in energy intake (EI) and eating behavior, potentially caused by fine motor dysfunction and eating-related symptoms, might contribute to this. The primary aim of this study was to investigate differences in objectively measured EI between groups of healthy controls (HC), early (ESPD) and advanced stage PD patients (ASPD) during a standardized lunch in a clinical setting. The secondary aim was to identify clinical features and eating behavior abnormalities that explain EI differences. All participants (n = 23 HC, n = 20 ESPD, and n = 21 ASPD) went through clinical evaluations and were eating a standardized meal (200 g sausages, 400 g potato salad, 200 g apple purée and 500 mL water) in front of two video cameras. Participants ate freely, and the food was weighed pre- and post-meal to calculate EI (kcal). Multiple linear regression was used to explain group differences in EI. ASPD had a significantly lower EI vs. HC (-162 kcal, p < 0.05) and vs. ESPD (-203 kcal, p < 0.01) when controlling for sex. The number of spoonfuls, eating problems, dysphagia and upper extremity tremor could explain most (86%) of the lower EI vs. HC, while the first three could explain ~50% vs. ESPD. Food component intake analysis revealed significantly lower potato salad and sausage intakes among ASPD vs. both HC and ESPD, while water intake was lower vs. HC. EI is an important clinical target for PD patients with an increased risk of weight loss. Our results suggest that interventions targeting upper extremity tremor, spoonfuls, dysphagia and eating problems might be clinically useful in the prevention of unintentional weight loss in PD. Since EI was lower in ASPD, EI might be a useful marker of disease progression in PD.

Sensory Profile of Adults with Reduced Food Intake and the Potential Roles of Nutrition and Physical Activity Interventions

The sensory profile, referring to sight, smell, taste, hearing, and touch, plays an essential role in optimizing the habitual intake of energy and macronutrients. However, specific populations, such as older adults, are known to have impaired energy intake. In this paper, the relevance of sensory impairments in this older population is described, and the extent to which nutritional and physical activity interventions can modulate these sensory responses when food intake is insufficient is explored. With aging, all senses deteriorate, and in most cases, such deteriorations diminish the nutritional response. The only exception is sight, for which both positive and negative impacts on nutritional response have been reported. From a prevention perspective, nutritional interventions have been understudied, and to date, only hearing is known to be positively affected by a good nutritional profile. In comparison, physical activity has been more frequently studied in this context, and is linked to an improved preservation of 4 senses. Regarding treatment, very few studies have directly targeted sensory training, and the focus of research has tended to be on nutrition and physical activity intervention. Sensory training, and nutritional and physical activity treatments all have beneficial effects on the senses. In the future, researchers should focus on exploring gaps in the literature specifically concerning prevention, treatment, and sensory response to understand how to improve the efficacy of current approaches. In order to maintain sensory acuity and recover from sensory impairment, the current state of knowledge supports the importance of improving nutritional habits as well as physical activity early on in life. A combined approach, linking a detailed lifestyle profile with the assessment of numerous senses and one or more interventional approaches (nutrition, physical activity, sensory training, etc.), would be required to identify effective strategies to improve the nutritional state of older individuals.

Diagnostic Accuracy, Item Analysis and Age Effects of the UPSIT Spanish Version in Parkinson's Disease

OBJECTIVE

The University of Pennsylvania Smell Identification Test (UPSIT) is the most commonly used test to detect olfactory impairment in Parkinson's disease (PD), but the cut-off score for clinical purposes is often difficult to establish because of age and sex effects. The current work aims to study the sensitivity and specificity of the UPSIT Spanish version and its accuracy in discriminating PD patients at different age groups from healthy controls (HC), and to perform an item analysis.

METHOD

Ninety-seven non-demented PD patients and 65 HC were assessed with the UPSIT Spanish version. Sensitivity, specificity, and diagnostic accuracy for PD were calculated. Multiple regression analysis was used to define predictors of UPSIT scores.

RESULTS

Using the normative cut-off score for anosmia (≤18), the UPSIT showed a sensitivity of 54.6% with a specificity of 100.0% for PD. We found that, using the UPSIT cut-off score of ≤25, sensitivity was 81.4% and specificity 84.6% (area under the receiver operating characteristic curve = 0.908). Diagnosis and age were good predictors of UPSIT scores (B = -10.948; p < .001; B = -0.203; p < .001). When optimal cut-off scores were considered according to age ranges (≤60, 61-70, and ≥71), sensitivity and specificity values were >80.0% for all age groups.

CONCLUSIONS

In the Spanish UPSIT version, sensitivity and specificity are improved when specific cut-off scores for different age groups are computed.

Chemosensory dysfunction in neurodegenerative diseases

A number of neurodegenerative diseases are accompanied by disordered smell function. The degree of dysfunction can vary among different diseases, such that olfactory testing can aid in differentiating, for example, Alzheimer's disease (AD) from major affective disorder and Parkinson's disease (PD) from progressive supranuclear palsy. Unfortunately, altered smell function often goes unrecognized by patients and physicians alike until formal testing is undertaken. Such testing uniquely probes brain regions not commonly examined in physical examinations and can identify, in some cases, patients who are already in the "preclinical" stage of disease. Awareness of this fact is one reason why the Quality Standards Committee of the American Academy of Neurology has designated smell dysfunction as one of the key diagnostic criteria for PD. The same recommendation has been made by the Movement Disorder Society for both the diagnosis of PD and identification of prodromal PD. Similar suggestions are proposed to include olfactory dysfunction as an additional research criterion for the diagnosis of AD. Although taste impairment, i.e., altered sweet, sour, bitter, salty, and umami perception, has also been demonstrated in some disorders, taste has received much less scientific attention than smell. In this review, we assess what is known about the smell and taste disorders of a wide range of neurodegenerative diseases and describe studies seeking to understand their pathologic underpinnings.

Flavor perception and the risk of malnutrition in patients with Parkinson's disease

Flavor perception involves both olfactory and gustatory function. In patients with Parkinson’s disease (PD), hyposmia is a frequent finding, as well as an increased risk of malnutrition. We performed a pilot study to investigate the relationship between flavor perception and risk of malnutrition in PD patients. 63 PD patients participated to perform an olfactory (Sniffin’ Sticks) and gustatory (Taste Strips) task, and a questionnaire to establish nutritional risk (MUST), which includes BMI measurements. The relationship between olfactory and gustatory function and BMI was analyzed using partial correlations, corrected for disease duration, and regression analysis. Patients displayed a high prevalence of hyposmia (68.3%), and a low prevalence (6.3%) of hypogeusia. A small, but significant correlation was found between olfactory function and BMI (r = 0.261, p = 0.038), and not for gustatory function and BMI (r = 0.137, p = 0.284). Hyposmia, and not hypogeusia, may contribute to weight loss in Parkinson’s disease, and hence increase the risk of malnutrition.

Weight Loss and Malnutrition in Patients with Parkinson's Disease: Current Knowledge and Future Prospects

Parkinson's Disease (PD) is currently considered a systemic neurodegenerative disease manifested with not only motor but also non-motor symptoms. In particular, weight loss and malnutrition, a set of frequently neglected non-motor symptoms, are indeed negatively associated with the life quality of PD patients. Moreover, comorbidity of weight loss and malnutrition may impact disease progression, giving rise to dyskinesia, cognitive decline and orthostatic hypotension, and even resulting in disability and mortality. Nevertheless, the underlying mechanism of weight loss and malnutrition in PD remains obscure and possibly involving multitudinous, exogenous or endogenous, factors. What is more, there still does not exist any weight loss and malnutrition appraision standards and management strategies. Given this, here in this review, we elaborate the weight loss and malnutrition study status in PD and summarize potential determinants and mechanisms as well. In conclusion, we present current knowledge and future prospects of weight loss and malnutrition in the context of PD, aiming to appeal clinicians and researchers to pay a closer attention to this phenomena and enable better management and therapeutic strategies in future clinical practice.

Early weight loss in parkinsonism predicts poor outcomes: Evidence from an incident cohort study

Objective:

To compare weight change over time in patients with Parkinson disease (PD), those with atypical parkinsonism, and matched controls; to identify baseline factors that influence weight loss in parkinsonism; and to examine whether it predicts poor outcome.

Methods:

We analyzed data from the Parkinsonism Incidence in North-East Scotland (PINE) study, an incident, population-based prospective cohort of parkinsonian patients and age- and sex-matched controls with annual follow-up. Mixed-model analysis described weight change in patients with PD, those with atypical parkinsonism, and controls. Baseline determinants of sustained clinically significant weight loss (>5% loss from baseline) and associations between early sustained weight loss and death, dementia, and dependency in parkinsonism were studied with Cox regression.

Results:

A total of 515 participants (240 controls, 187 with PD, 88 with atypical parkinsonism) were followed up for a median of 5 years. At diagnosis, atypical parkinsonian patients had lower body weights than patients with PD, who were lighter than controls. Patients with PD lost weight more rapidly than controls, and weight loss was most rapid in atypical parkinsonism. After multivariable adjustment for potential confounders, only age was independently associated with sustained clinically significant weight loss (hazard ratio [HR] for 10-year age increase 1.83, 95% confidence interval [CI] 1.44–2.32). Weight loss occurring within 1 year of diagnosis was independently associated with increased risk of dependency (HR 2.11, 95% CI 1.00–4.42), dementia (HR 3.23, 95% CI 1.40–7.44), and death (HR 2.23, 95% CI 1.46–3.41).

Conclusion:

Weight loss occurs in early parkinsonism and is greater in atypical parkinsonism than in PD. Early weight loss in parkinsonism has prognostic significance, and targeted dietary interventions to prevent it may improve long-term outcomes.

Predictors of weight loss in early treated Parkinson's disease from the NET-PD LS-1 cohort

Weight loss is a common symptom of Parkinson's disease and is associated with impaired quality of life. Predictors of weight loss have not been studied in large clinical cohorts. We previously observed an association between change in body mass index and change in Unified Parkinson's Disease Rating Scale (UPDRS) motor and total scores. In this study, we performed a secondary analysis of longitudinal data (1-6 years) from 1619 participants in the NINDS Exploratory Trials in PD Long-term Study-1 (NET-PD LS1) to explore predictors of weight loss in a large prospective clinical trial cohort of early treated Parkinson's disease. The NET-PD LS1 study was a double-blind randomized placebo controlled clinical trial of creatine monohydrate 10 gm/day in early treated PD (within 5 years of diagnosis and within 2 years of starting dopaminergic medications). Linear mixed models were used to estimate the effect of baseline clinical covariates on weight change over time. On average, participants lost only 0.6 kg per year. Higher age, baseline weight, female gender, higher baseline UPDRS scores, greater postural instability, difficulty eating and drinking, lower cognitive scores and baseline levodopa use (compared to dopamine agonists) were all associated with weight loss. Surprisingly baseline difficulty swallowing, dyskinesia, depression, intestinal hypomotility (constipation) and self-reported nausea/vomiting/anorexia were not significantly associated with weight loss in this cohort of early treated Parkinson's disease patients. On average, participants with Parkinson's disease experience little weight loss during the first 1-6 years after starting dopaminergic replacement therapy, however levodopa use and postural instability were both predictors of early weight loss. Trial Registration clinicaltrials.gov identifier# NCT00449865.

Weight in Parkinson's Disease: Phenotypical Significance

Body weight in Parkinson's disease (PD) is a significant nonmotor feature. Weight homeostasis is a complex physiological process and gets deranged in PD patients leading to changes in weight. While both the low and high body weight have been reported as risk factors for PD, the majority of PD patients have a lower weight and a subset of patients lose weight during the course of the disease, while a small proportion gain weight. A number of clinical parameters such as older age, impaired cognition, severity of disease, and an imbalance of food intake determined by satiety and hunger hormones have been reported to be associated with but not the cause of weight change. Low body weight and weight loss have a negative impact on disease severity, dyskinesia quality of life, and mortality indicative of disease progression. An early assessment of olfactory impairment seems to identify patients at risk of weight loss, the patients with more severe olfactory loss-anosmic group, lose weight as compared to the patients with some preservation of olfaction, the hyposmic group. Higher levodopa dose per kilogram body weight increases the risk of dyskinesia, higher body weight seems to be protective against this complication. The identification of PD patients according to the nonmotor phenotype of "Park-olfaction-weight-phenotype" and the "olfaction-weight-dyskinesia" triad should help to develop strategies to prevent weight reduction and improve general health and complications of PD patients. The phenotype seems to reflect a differential prodromal pathology and influence clinical disease. Higher body weight patients would benefit from life style changes to achieve a healthy profile. Weight monitoring and weight orientated approach to management of PD patients should help to improve their outcome. Body weight change might be a surrogate to disease progression and may be used to investigate neuroprotection strategies.

A multifactorial study on nutritional status, binge eating and physical activity as main factors directly influencing body weight in Parkinson's disease

Weight lossisa multifactorial disorder commonly affecting Parkinson's disease patients. The aim of this study was to investigate the relationship between body weight, nutritional status, physical activity, and Parkinson's disease-related factors. A total of 114 consecutive Parkinson's disease patients without dietary restrictions were evaluated prospectively with respect to: nutritional status (Mini Nutritional Assessment), physical activity level (Yale Physical Activity Survey), MDS-UPDRS score, olfactory function, depression, cognitive functionand impulse-control disorders, among other variables. Structural equation modeling was used to build multivariate models and to calculate standardized regression weights (srw) for pairs of variables, which are homologous to correlation coefficients, taking into account the effects of all other variables in the model. Sixty (53%) patients were males. Mean age was 66.1 ± 9.8 years and mean disease duration was 8.3 ± 5.6 years. Longer disease duration was negatively related to nutritional status (srw = -0.25; p = 0.01). UPDRS II + III score was associated with reduced cognitive function (srw = -0.39; p = 0.01), which was positivelyrelated to nutritional status (srw = 0.23; p = 0.01). Finally, nutritional status was positively related to body weight (srw = 0.22, p < 0.01). Binge eating and physical activity were also directly and positively related to body weight (srw = 0.32; p = 0.001 and srw = 0.23; p = 0.001). Nutritional status, binge eating and physical activity were directly and independently related to body weight in our sample of Parkinson's disease patients. Therefore, physicians should actively explore nutritional status and binge eating in Parkinson's disease patients to avoid alterations in body weight regulation. Effects of physical activity should be further explored.

Body weight and dysautonomia in early Parkinson's disease

OBJECTIVES

Patients with Parkinson's disease (PD) begin to lose weight several years before diagnosis, which suggests weight variation is associated with some factor(s) that precede the onset of motor symptoms. This study aimed to investigate the association of autonomic nervous system with body weight in patients with PD.

MATERIALS AND METHODS

The subjects were 90 patients with early de novo PD. We examined the associations of body mass index (BMI) with sympathetic nervous activity reflected in orthostatic intolerance or cardiac uptake of ¹²³ I-metaiodobenzylguanidine and parasympathetic nervous activity reflected in constipation or heart rate variability (HRV).

RESULTS

Twelve patients (13.3%) were overweight (BMI>25 kg/m² ), 62 patients (68.9%) were normal-weight (18.5≦BMI<25 kg/m² ), and 16 patients (17.8%) were underweight (BMI<18.5 kg/m² ). Underweight patients had greater disease severity and decrease in blood pressure on head-up tilt-table testing, higher cardiac washout ratio of ¹²³ I-metaiodobenzylguanidine, and lower HRV and complained of constipation more often than those with normal-weight or overweight patients. On multiple regression analyses, the correlation of these variables with BMI maintained statistical significance after adjustment for age, sex, symptom duration, and motor subtype.

CONCLUSIONS

Dysautonomia and disease severity are closely related to body weight independently of age, sex, symptom duration, and motor subtype. Dysautonomia may play a partial role on weight variation in the early stage of PD.

Synucleinopathies: common features and hippocampal manifestations

Parkinson's disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA) are three major synucleinopathies characterized by α-synuclein-containing inclusions in the brains of patients. Because the cell types and brain structures that are affected vary markedly between the disorders, the patients have different clinical manifestations in addition to some overlapping symptoms, which are the basis for differential diagnosis. Cognitive impairment and depression associated with hippocampal dysfunction are frequently observed in these disorders. While various α-synuclein-containing inclusions are found in the hippocampal formation, increasing evidence supports that small α-synuclein aggregates or oligomers may be the real culprit, causing deficits in neurotransmission and neurogenesis in the hippocampus and related brain regions, which constitute the major mechanism for the hippocampal dysfunctions and associated neuropsychiatric manifestations in synucleinopathies.

Presynaptic dopaminergic terminal imaging and non-motor symptoms assessment of Parkinson's disease: evidence for dopaminergic basis?

Parkinson's disease (PD) is now considered to be a multisystemic disorder consequent on multineuropeptide dysfunction including dopaminergic, serotonergic, cholinergic, and noradrenergic systems. This multipeptide dysfunction leads to expression of a range of non-motor symptoms now known to be integral to the concept of PD and preceding the diagnosis of motor PD. Some non-motor symptoms in PD may have a dopaminergic basis and in this review, we investigate the evidence for this based on imaging techniques using dopamine-based radioligands. To discuss non-motor symptoms we follow the classification as outlined by the validated PD non-motor symptoms scale.

Non-Motor symptoms in Portuguese Parkinson's Disease patients: correlation and impact on Quality of Life and Activities of Daily Living

The prevalence of non-motor symptoms (NMS) in Parkinson’s Disease (PD) has varied between studies. Their interrelation isn’t totally understood. Also, the relative importance of each symptom, regarding its impact on activities of daily living (ADL) and health related quality of life (HRQL), remains debatable. We assessed all PD patients attending a Portuguese tertiary movement disorders center during one year (n = 134), with ADL, HRQL and other clinical scales approved for identifying the most relevant NMS in PD. All patients had at least one NMS. Sleep/fatigue, affect/cognition, attention/memory were the most frequent complaints, and their prevalence, above 80%, was higher than in most studies. There were significantly correlations between: sleepiness, psychosis and cognition; gastrointestinal, cardiovascular symptoms and pain; depression and apathy; anxiety and insomnia; olfaction, weight and hyperhidrosis. Depression/apathy exerted the strongest influence on HRQL and non-tremor motor dysfunction on ADL. Compared to studies in other countries, we found a higher prevalence of NMS, which could be specific of this population. The interrelation between NMS could be related to degeneration of different brain structures. NMS exert a stronger influence than MS in HRQL, which should be taken in account regarding treatment options.

Dietary habits and neurological features of Parkinson's disease patients: Implications for practice

BACKGROUND & AIMS

Parkinson's disease (PD) patients can benefit considerably from appropriate nutritional care, particularly from diet. However, there is limited evidence on the eating habits of PD patients and their relationship with the features of the disease.

METHODS

We conducted a large case-control study. Consecutive PD patients (N = 600) receiving systematic nutritional care and healthy controls (N = 600) matched (1:1) for age, gender, education, physical activity level and residence were studied using a 66-item food frequency questionnaire. The relationship between dietary habits and the following features of PD were investigated in patients: body weight, energy balance, constipation, and levodopa therapy (dose) and its related motor complications.

RESULTS

PD patients had lower BMI and reported higher food intake than controls. BMI was found to be inversely associated with disease duration and severity, and levodopa-related motor complications, whereas energy intake was positively associated with these variables. An increase in protein intake by 10 g over physiological requirements (0.8 g/kg/day) corresponded to a mean increase in levodopa dose of 0.7 mg/kg/day. Constipation was also associated with higher levodopa requirements. Finally, protein intake and its distribution throughout the day influenced levodopa-related motor complications.

CONCLUSION

The management of protein intake and the treatment of constipation should be considered to be an integral part of the care of PD patients. Attention should always be focused on energy intake also. This would result in the maintenance of nutritional status, the optimization of levodopa-therapy and the minimization of its related motor complications.

Avaliação nutricional e o uso da levodopa com refeições proteicas em pacientes com doença de Parkinson do município de Macaé, Rio de Janeiro

Resumo A doença de Parkinson (DP) é caracterizada pela redução da dopamina no sistema nervoso central. Apresenta progressão gradativa e é conhecida, principalmente, por tremores e dificuldade em realizar movimentos. Estudos demonstram que há significativa alteração do estado nutricional nos pacientes com DP. O principal medicamento utilizado no tratamento dos pacientes é a levodopa e a sua administração, sem respeitar o intervalo de no mínimo 30 minutos antes ou uma hora após as refeições, pode diminuir o efeito farmacológico da substância devido à interação droga-nutriente. Este estudo objetivou identificar, no município de Macaé-RJ, pacientes com DP em risco nutricional e o consumo proteico associado ao uso da levodopa. Trata-se de um estudo transversal, quantitativo e descritivo.Os instrumentos utilizados foram a Mini Avaliação Nutricional (MAN) e o registro alimentar estimado de três dias. A análise foi descritiva. Para compor a amostra, foi realizado um levantamento do número de pacientes com diagnóstico de DP de dois programas da Secretaria de Saúde e da Associação Parkinson de Macaé. Foram avaliados 40 indivíduos, desses, 57,5% eram do sexo masculino. Apresentaram risco de desnutrição ou desnutrição pela MAN 62,5% dos pacientes, caracterizando déficit nutricional. A ingestão proteica da população foi de 1,4g/Kg/dia. A maior ingestão de proteínas foi no período do dia, considerando as refeições compreendidas entre o café da manhã e o lanche da tarde. O consumo pela população nesse período foi de 74,7% da proteína total. Dos idosos, 75,0% ingeriam seus medicamentos compostos de levodopa simultaneamente às refeições ou não, seguindo o intervalo recomendado pela ANVISA. O estudo verificou que a maioria dos indivíduos apresentou risco nutricional, a maior parte realizava uma ingestão diária total hiperproteica, sendo o conteúdo proteico mal distribuído nas refeições ao longo do dia, além do não cumprimento ao intervalo recomendado da levodopa.

Combined DaT imaging and olfactory testing for differentiating parkinsonian disorders

OBJECTIVE

Dopamine transporter (DaT) imaging with single photon emission computed tomography (SPECT) detects loss of striatal dopaminergic innervation with very high sensitivity. It cannot readily distinguish idiopathic Parkinson's disease (iPD) and dementia with Lewy bodies (DLB) from atypical disorders (aPD). However, most iPD/DLB patients are hyposmic, whereas the majority of aPD patients were reported to have intact olfaction. For this reason, we conducted a longitudinal follow-up study to investigate the power of combined DaT imaging and olfactory testing to predict the final diagnosis of the patients.

MATERIALS AND METHODS

A total of 129 patients received [123I]FP-CIT SPECT and olfactory testing at baseline assessment. Clinical follow-up 30 ± 12 months later was the diagnostic standard of truth. A normative dataset of 24 healthy controls was used for comparison.

RESULTS

Baseline DaT imaging predicted a dopamine-deficient diagnosis with 98% sensitivity and 98% specificity. The combined DaT/olfactory testing correctly classified 91% of patients as iPD/DLB (PPV 91%). The PPV rose to 97% or greater in anosmic patients. In contrast, only 45% of aPD patients were categorised correctly by combined DaT/olfactory testing - mainly because of the presence of normosmic iPD patients.

CONCLUSIONS

In patients with an abnormal DaT SPECT, hyposmia yields an a posteriori likelihood of iPD/DLB of > 90%. In contrast, a finding of normosmia only increases the a posteriori likelihood of aPD to approximately the 50%.

Body weight and food intake in Parkinson's disease. A review of the association to non-motor symptoms

Research on eating behaviours has extensively highlighted that cognitive systems interact with the metabolic system in driving food intake and in influencing body weight regulation. Parkinson's disease is a good model for studying these complex interactions since alterations in both body weight and cognitive domains have been frequently reported among these patients. Interestingly, even if different non-motor symptoms may characterize the course of the disease, their contribution to weight and food preference has been poorly investigated. This review describes body weight alterations and eating habits in patients with Parkinson's disease, including those who underwent deep brain stimulation surgery. In particular, the review considers the link between non-motor symptoms, affecting sensory perception, cognition, mood and motivation, and food intake and weight alterations. The take home message is twofold. First, we recommend a comprehensive approach in order to develop effective strategies in the management of patients' weight. Second, we also suggest that investigating this issue in patients with Parkinson's disease may provide some useful information about the mechanisms underlying food and weight regulation in healthy subjects.

Prognostic significance of weight changes in Parkinson's disease: the Park–weight phenotype

SUMMARY 

Neurodegenerative Parkinson's disease (PD) is associated with a changing profile of weight as the disease advances. Whilst some patients gain weight, a significant proportion of patients lose weight. PD patients have a lower body weight as compared with non-PD controls. Weight loss is not a benign phenomenon. Patients with lower initial body weight and weight losers have a higher risk of developing dyskinesia. There is a relationship between body weight and levodopa dose, patients with higher levodopa dose per kilogram are at a higher risk of dyskinesia, the risk escalates above 6 mg per kilogram. Lower weight patients have risk of undernutrition and the associated disease pathology due to frailty. Weight losers are at risk of higher mortality and poor quality of life. PD patients should be assessed for body weight and the dose of levodopa be adjusted according to periodic weight changes, supplemented by other dopaminergic medications. Patients at risk of weight loss may be identified by their severe loss of olfaction since there seems to exist the olfaction–weight–dyskinesia phenotype. Measures should be taken to prevent weight loss in at-risk patients to prevent low-weight-related adverse outcomes in PD patients. These measures may protect PD patients from motor and non-motor adverse effects as the disease advances.

Olfactory loss as a supporting feature in the diagnosis of Parkinson's disease: a pragmatic approach

There is ample evidence from a large number of clinical and pathological studies of an early involvement of olfactory bulbs and cortex in the Lewy body pathology in idiopathic Parkinson's disease (iPD), the olfactory system being one of the first targets of degeneration in this condition. The olfactory dysfunction may be measurably present at the time of initial presentation and progresses in a proportion of patients as the disease advances. Patients with iPD have a more severe olfactory loss as compared to multisystem atrophy whereas the syndromes of corticobasal degeneration and progressive supranuclear palsy have no olfactory loss. A proportion of drug induced parkinsonism may have olfactory loss indicative of primary pathology of dopaminergic degeneration in these patients. Unlike single photon emission tomography, formal measurement of olfaction would provide a supportive role in diagnosing or excluding iPD depending on the duration of an individual patient's parkinsonian symptoms. Whilst olfaction may be only minimally impaired in early stages and may thus not help to differentiate from other syndromes, an intact olfaction in patients with parkinsonism of few years' duration would indicate a non-iPD pathology. Olfactory measurement is easy, cheap and now easily available in a number of tests, and olfactory assessment at different stages of parkinsonism should be used as a diagnostic aid for idiopathic PD and would enhance the diagnostic accuracy of iPD when used in conjunction with the UK Parkinson's disease society Brain Bank supportive criteria for diagnosis of idiopathic Parkinson's disease.