Low cardiometabolic risk in Parkinson's disease is independent of nutritional status, body composition and fat distribution

An exploratory study on the ability of manganese to supplement rotenone neurotoxicity in rats

Parkinson's disease (PD) is a complex disorder, primarily of idiopathic origin, with environmental stressors like rotenone and manganese linked to its development. This study explores their potential interaction and resulting neurotoxicity, aiming to understand how environmental factors contribute to PD. In an eight-day experiment, male Wistar rats weighing 280-300 g were subjected to rotenone, manganese, or a combination of both. Various parameters were assessed, including body weight, behavior, serum markers, tissue damage, protein levels (tyrosine hydroxylase, Dopamine- and cAMP-regulated neuronal phosphoprotein -DARPP-32-, and α-synuclein), and mitochondrial function. Manganese heightened rotenone's impact on reducing food intake without causing kidney or liver dysfunction. However, the combined exposure intensified neurotoxicity, which was evident in augmented broken nuclei and decreased tyrosine hydroxylase and DARPP-32 levels in the striatum. While overall mitochondrial function was preserved, co-administration reduced complex IV activity in the midbrain and liver. In conclusion, our findings revealed a parallel toxic effect induced by rotenone and manganese. Notably, while these substances do not target the same dopaminergic regions, a notable escalation in toxicity is evident in the striatum, the brain region where their toxic effects converge. This study highlights the need for further exploration regarding the interaction of environmental factors and their possible impact on the etiology of PD.

Contribution of Nutritional, Lifestyle, and Metabolic Risk Factors to Parkinson's Disease

BACKGROUND

Modifiable risk factors for Parkinson's disease (PD) are poorly known.

OBJECTIVES

The aim is to evaluate independent associations of different nutritional components, physical activity, and sedentary behavior and metabolic factors with the risk of PD.

METHODS

In this population-based prospective cohort study using the data of the United Kingdom Biobank (from 2006-2010), 502,017 men and women who were free from PD (International Classification of Diseases 10th edition; "G20") at baseline were included. We implemented a Cox proportion hazard's model to evaluate the associations of different levels of physical activity, sitting time, sleep habits, diet quality, alcohol and coffee consumption, smoking, and body mass index with PD risk, adjusting for several confounding variables.

RESULTS

During a median follow-up of 12.8 years, lifestyle factors including vigorous physical activity (hazard ration [HR] = 0.84; 95% confidence interval [CI], 0.75-0.94), low-to-moderate sitting time (HR = 0.89; 95% CI, 0.81-0.97), and high sleep quality (HR = 0.89; 95% CI, 0.80-0.99) were associated with a reduced risk of PD. Small amounts of coffee (HR = 0.88; 95% CI, 0.82-0.95), red meat (HR = 0.86; 95% CI, 0.76-0.97), and current smoking (HR = 0.65; 95% CI, 0.56-0.75) were also associated with a lower risk of PD, whereas alcohol intake (HR = 1.29; 95% CI, 1.06-1.56) with higher PD risk. Secondary analysis, including metabolic risk factors, confirmed these findings and highlighted the potential protective effect of plasma vitamin D and uric acid, but of low-density lipoprotein-cholesterol, triglycerides, and C-reactive protein as well.

CONCLUSIONS

Vigorous physical activity, reduced sitting time, good sleep quality together with small coffee intake and vitamin D supplementation are potentially neuroprotective lifestyle interventions for the prevention of PD. © 2024 International Parkinson and Movement Disorder Society.

Clinical advances in analytical profiling of signature lipids: implications for severe non-communicable and neurodegenerative diseases

BACKGROUND

Lipids play key roles in numerous biological processes, including energy storage, cell membrane structure, signaling, immune responses, and homeostasis, making lipidomics a vital branch of metabolomics that analyzes and characterizes a wide range of lipid classes. Addressing the complex etiology, age-related risk, progression, inflammation, and research overlap in conditions like Alzheimer's Disease, Parkinson's Disease, Cardiovascular Diseases, and Cancer poses significant challenges in the quest for effective therapeutic targets, improved diagnostic markers, and advanced treatments. Mass spectrometry is an indispensable tool in clinical lipidomics, delivering quantitative and structural lipid data, and its integration with technologies like Liquid Chromatography (LC), Magnetic Resonance Imaging (MRI), and few emerging Matrix-Assisted Laser Desorption Ionization- Imaging Mass Spectrometry (MALDI-IMS) along with its incorporation into Tissue Microarray (TMA) represents current advances. These innovations enhance lipidomics assessment, bolster accuracy, and offer insights into lipid subcellular localization, dynamics, and functional roles in disease contexts.

AIM OF THE REVIEW

The review article summarizes recent advancements in lipidomic methodologies from 2019 to 2023 for diagnosing major neurodegenerative diseases, Alzheimer's and Parkinson's, serious non-communicable cardiovascular diseases and cancer, emphasizing the role of lipid level variations, and highlighting the potential of lipidomics data integration with genomics and proteomics to improve disease understanding and innovative prognostic, diagnostic and therapeutic strategies.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Clinical lipidomic studies are a promising approach to track and analyze lipid profiles, revealing their crucial roles in various diseases. This lipid-focused research provides insights into disease mechanisms, biomarker identification, and potential therapeutic targets, advancing our understanding and management of conditions such as Alzheimer's Disease, Parkinson's Disease, Cardiovascular Diseases, and specific cancers.

Evaluation of sarcopenia and phase angle in elderly patients with Parkinson's Disease

PURPOSE

To investigate sarcopenia and related factors and to determine the disease-specific phase angle (PhA) cut-off score in detecting sarcopenia in elderly patients with Parkinson's Disease (PD).

METHODS

This cross-sectional study was conducted with 89 participants. The Mini-Nutritional Assessment (MNA), the Eating Attitude Test-10 (EAT-10), the Physical Activity Scale for The Elderly (PASE) questionnaire and the Hoehn-Yahr scale have been used. Additionally, anthropometric measurements were performed. The diagnosis of sarcopenia was based on the new consensus published by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2). PhA has been performed by Bioelectrical Impedance Analysis (BIA) with Tanita MC 780®.

RESULTS

The mean age was of the participants 68.9 ± 6.4 years, and 57.3% were male. The prevalence of sarcopenia was 12.3%. PhA, malnutrition, age, disease severity, low calf circumference (CC), low body mass index (BMI), the difference between the pre-diagnosis and current weight loss, dopaminergic treatment, and low PASE score were associated with sarcopenia. The cut-off value of the PhA in terms of the ability to identify sarcopenia was <4.5o with a sensitivity of 53.3% and a specificity of 93.2% (p = 0.001). When we grouped the PhA of the patients according to this cut-off score, it was seen that 14.6% of them were sarcopenic. Age, disease severity, PASE score and hand grip strength were significantly related to both sarcopenia and PhA.

CONCLUSION

It is important to be aware of sarcopenia and related factors at an early stage in Parkinson's patients. Because of disease-related symptoms, it may be more appropriate to use a disease-specific PhA cut-off score in the definition of sarcopenia.

Association between Low Blood Pressure and Subsequent Risk of Parkinson's Disease in Older Adults Aged ≥75 Years

INTRODUCTION

The association between blood pressure (BP) and incidence of Parkinson's disease (PD) in older adults remains uncertain. Therefore, this study aimed to investigate the association between BP (high or low) and PD incidence in adults aged ≥75 years.

METHODS

In this nationwide population-based cohort study, we enrolled participants aged ≥75 years without a prior PD diagnosis who had undergone health examination provided by the Korean National Health Insurance Service at least once from January 1, 2009, to December 31, 2012. The participants were followed up until December 31, 2019, or the date of their death. The Cox proportional hazards model was used to assess the risk of PD depending on systolic BP (SBP), diastolic BP (DBP), and pulse pressure.

RESULTS

Overall, 963,525 participants were enrolled in the analysis and followed up until December 31, 2019, or the date of death (40.7% male, mean age 78.5 ± 3.6 years). The mean SBP and DBP were 131.4 ± 16.7 and 77.9 ± 10.3 mm Hg, respectively. During the 10-year follow-up period, 16,414 (1.7%) newly diagnosed cases of PD were reported. A significant inverse dose-response association was found between SBP and PD incidence. In the subgroup analysis, this association was maintained for most variables, including sex, use of antihypertensive medication, comorbidities, alcohol consumption, physical activity, and body mass index, except for smoking status.

CONCLUSION

Lower SBP and DBP were associated with a higher PD incidence in older adults. These results may have substantial implications for determining the optimal BP control target in adults aged ≥75 years.

Effects of Exercise Training on Muscle Quality in Older Individuals: A Systematic Scoping Review with Meta-Analyses

BACKGROUND

The quantity and quality of skeletal muscle are important determinants of daily function and metabolic health. Various forms of physical exercise can improve muscle function, but this effect can be inconsistent and has not been systematically examined across the health-neurological disease continuum. The purpose of this systematic scoping review with meta-analyses was to determine the effects and potential moderators of exercise training on morphological and neuromuscular muscle quality (MMQ, NMQ) in healthy older individuals. In addition and in the form of a scoping review, we examined the effects of exercise training on NMQ and MMQ in individuals with neurological conditions.

METHODS

A systematic literature search was performed in the electronic databases Medline, Embase, and Web of Science. Randomized controlled trials were included that examined the effects of exercise training on muscle quality (MQ) in older individuals with and without neurological conditions. Risk of bias and study quality were assessed (Cochrane Risk of Bias Tool 2.0). We performed random-effects models using robust variance estimation and tested moderators using the approximate Hotelling-Zhang test.

RESULTS

Thirty studies (n = 1494, 34% females) in healthy older individuals and no studies in individuals with neurological conditions were eligible for inclusion. Exercise training had small effects on MMQ (g = 0.21, 95% confidence interval [CI]: 0.03-0.40, p = 0.029). Heterogeneity was low (median I² = 16%). Training and demographic variables did not moderate the effects of exercise on MMQ. There was no association between changes in MMQ and changes in functional outcomes. Exercise training improved NMQ (g = 0.68, 95% CI 0.35-1.01, p < 0.000) across all studies, in particular in higher-functioning older individuals (g = 0.72, 95% CI 0.38-1.06, p < 0.001), in lower extremity muscles (g = 0.74, 95% CI 0.35-1.13, p = 0.001), and after resistance training (g = 0.91; 95% CI 0.42-1.41, p = 0.001). Heterogeneity was very high (median I² = 79%). Of the training and demographic variables, only resistance training moderated the exercise-effects on NMQ. High- versus low-intensity exercise moderated the exercise-effects on NMQ, but these effects were considered unreliable due to a low number of studies at high intensity. There was no association between changes in NMQ and changes in functional outcomes.

CONCLUSION

Exercise training has small effects on MMQ and medium-large effects on NMQ in healthy older individuals. There was no association between improvements in MQ and increases in muscle strength, mobility, and balance. Information on dose-response relations following training is currently lacking. There is a critical gap in muscle quality data for older individuals with lower function and neurological conditions after exercise training. Health practitioners should use resistance training to improve muscle function in older individuals. Well-designed studies are needed to examine the relevance of exercise training-induced changes in MQ in daily function in older individuals, especially to those with lower function and neurological conditions.

Prevalence of Malnutrition in Patients with Parkinson's Disease: A Systematic Review

OBJECTIVES

This systematic review analyzed the prevalence of malnutrition in patients with Parkinson's Disease.

STUDY DESIGN

a systematic review.

METHOD

Four databases-Cochrane, PubMed, Embase and Web of Science-were searched from October 2021 to June 2022 by two independent researchers. The inclusion criteria were as follows: patients above 18 years old with confirmed Parkinson's Disease, performed screening nutritional assessment, cohort studies, case-control studies, and cross-sectional studies. Patients without Parkinson's Disease and with other parkinsonian syndromes were excluded.

RESULTS

49 studies were included in this systematic review. Patients ranged in age from 20 to 96 years. There were 5613 subjects included. According to Mini Nutritional Assessment, 23.9% (n = 634) participants were at risk of malnutrition and 11.1% (n = 294) were malnourished. According to BMI score, most patients were either obese or overweight.

CONCLUSIONS

the prevalence of malnutrition or risk of malnutrition in the study group was significant. Therefore, more specific and detailed studies on the prevalence of malnutrition in patients with Parkinson's Disease are needed.

Genotypic-Phenotypic Analysis, Metabolic Profiling and Clinical Correlations in Parkinson's Disease Patients from Tamil Nadu Population, India

Parkinson's disease (PD) is an ageing disorder caused by dopaminergic neuron depletion with age. Growing research in the field of metabolomics is expected to play a major role in PD diagnosis, prognosis and therapeutic development. In this study, we looked at how SNCA and GBA1 gene mutations, as well as metabolomic abnormalities of kynurenine and cholesterol metabolites, were linked to alpha-synuclein (α-syn) and clinical characteristics in three different PD age groups. In all three age groups, a metabolomics analysis revealed an increased amount of 27-hydroxycholesterol (27-OHC) and a lower level of kynurenic acid (KYNA). The effect of 27-OHC on SNCA and GBA1 modifications was shown to be significant (P < 0.05) only in the A53T variant of the SNCA gene in late-onset and early-onset PD groups, whereas GBA1 variants were not. Based on the findings, we observed that the increase in 27-OHC would have elevated α-syn expression, which triggered the changes in the SNCA gene but not in the GBA1 gene. Missense variations in the SNCA and GBA1 genes were investigated using the sequencing technique. SNCA mutation A53T has been linked to increased PD symptoms, but there is no phenotypic link between GBA1 and PD. As a result of the data, we hypothesise that cholesterol and kynurenine metabolites play an important role in PD, with the metabolite 27-OHC potentially serving as a PD biomarker. These findings will aid in the investigation of pathogenic causes as well as the development of therapeutic and preventative measures for PD.

Lower Blood Lipid Level Is Associated with the Occurrence of Parkinson's Disease: A Meta-Analysis and Systematic Review

BACKGROUND

The changes of blood lipid levels in patients with Parkinson's disease (PD) and its clinical relevance remain unclear. We aimed to evaluate the potential association of blood lipid and the occurrence of PD, to provide evidence to the clinical treatment and nursing care of PD.

METHODS

We searched PubMed, Medline, Web of Science, Cochrane Library, Wanfang Database, Weipu Database, and China National Knowledge Infrastructure for studies related to the blood lipid levels and PD until November 30, 2021. Two researchers independently screened the literature and extricated the data including the levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of included studies. RevMan5.3 and Stata 12.0 software were used for statistical processing and analysis.

RESULTS

A total of 15 cohort studies with 9740 participants involving 2032 PD patients and 7708 controls were included. Meta-analysis indicated that TC (SMD = -0.29, 95% CI -0.55∼-0.03, P=0.04), TG (SMD = -16.83, 95% CI -20.71∼-12.95, P < 0.001), HDL-C (SMD = -0.14, 95% CI -0.26∼-0.02, P < 0.001) and LDL-C (SMD = -0.26, 95% CI -0.50∼-0.01, P=0.04) level in the PD patients was significantly lower than that of health controls. Sensitivity analysis indicated that the results were stable. No significant publication bias was found between the synthesized outcomes.

CONCLUSIONS

Lower blood TC, TG, HDL-C, and LDL-C level are associated with the occurrence of PD. Limited by sample size and study population, further high-quality, large-sample clinical trials in different areas are needed to further determine the relationship between blood lipids and PD in the future.

Serum lipids and the pathogenesis of Parkinson's disease: A systematic review and meta-analysis

BACKGROUND

The role of serum lipids in the pathogenesis of Parkinson's disease (PD) remains unclear, and the results of previous reports remain conflicting. We aimed to conduct this systematic review and meta-analysis to identify the potential relationships of blood lipids and the pathogenesis of PD.

METHODS

PubMed, Medline, Web of Science, Cochrane Library, and China National Knowledge Infrastructure (CNKI) databases were searched from inception to March 31, 2020, to identify potential studies with case-control or cohort study design on the relationship of serum lipids and PD. Stata 15.1 software was used for data syntheses after extraction of relevant data.

RESULTS

A total of 12 studies with 1506 PD patients and 7330 healthy controls were included. There were no significant differences in the TC (SMD = -0.08, 95% CI [-0.45, 0.33]), LDL-C (SMD = -0.12, 95% CI [-0.46, 0.18]), and TG (SMD = -0.05, 95% CI [-0.18, 0.06]) among PD patients and healthy controls. There was significant difference (SMD = -0.32, 95% CI [-0.42, -0.25]) in the TG level among PD patients and healthy controls. Subgroup analysis by Asian and non-Asian countries indicated that geographical location was not the source of heterogeneity. And no significant publication bias was found (all P > .05).

CONCLUSIONS

TG serum levels are significantly lower in PD patients, more studies are needed to further elucidate role of lipid in the PD development.

Shared genetic etiology between Parkinson's disease and blood levels of specific lipids

Parkinson’s disease (PD) is characterized by the degeneration of dopaminergic neurons in the substantia nigra and the formation of Lewy bodies. The mechanisms underlying these molecular and cellular effects are largely unknown. Previously, based on genetic and other data, we built a molecular landscape of PD that highlighted a central role for lipids. To explore which lipid species may be involved in PD pathology, we used published genome-wide association study (GWAS) data to conduct polygenic risk score-based analyses to examine putative genetic sharing between PD and blood levels of 370 lipid species and lipid-related molecules. We found a shared genetic etiology between PD and blood levels of 25 lipids. We then used data from a much-extended GWAS of PD to try and corroborate our findings. Across both analyses, we found genetic overlap between PD and blood levels of eight lipid species, namely two polyunsaturated fatty acids (PUFA 20:3n3-n6 and 20:4n6), four triacylglycerols (TAG 44:1, 46:1, 46:2, and 48:0), phosphatidylcholine aa 32:3 (PC aa 32:3) and sphingomyelin 26:0 (SM 26:0). Analysis of the concordance—the agreement in genetic variant effect directions across two traits—revealed a significant negative concordance between PD and blood levels of the four triacylglycerols and PC aa 32:3 and a positive concordance between PD and blood levels of both PUFA and SM 26:0. Taken together, our analyses imply that genetic variants associated with PD modulate blood levels of a specific set of lipid species supporting a key role of these lipids in PD etiology.

Serum lipid profile of Parkinson's disease patients: A study from the Northwest of Iran

BACKGROUND

Parkinson's disease (PD) is defined as a long-lasting, neurological illness. Low levels of serum lipid fractions are related with a high risk of PD. Current investigation was designed to evaluate the concentration blood lipid fractions in patients suffering from PD and compared with healthy subjects.

METHODS

This case-control study was conducted from February 2016 to September 2018 in Tabriz University of Medical Sciences, Tabriz, Iran. The present investigation consisted of 75 persons who had PD and 75 normal people. The blood levels of lipid fractions were measured by concentrations of total cholesterol (TC), serum triglycerides (TG), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), and total cholesterol. The results were analyzed with SPSS software using Kolmogorov-Smirnov, chi-square, and student's t-test.

RESULTS

Serum level of TG was remarkably lower in patients with PD (111.92±8.75 mg/dL) compared with healthy subjects (123.64±9.97 mg/dL, P=0.008). Furthermore, we saw an important difference in the level of LDL-C (P=0.001) and TC (P=0.004) between the two groups. However, there was not any observed meaningful difference in the serum concentrations of HDL-C between the studied groups (P=0.135).

CONCLUSION

Our results showed that the serum concentration of TG, LDL-C, and TC are noticeably lower in the PD suffering patients. Further investigations are needed to provide comprehensive information on the participants' cognitive layout and subsequent actions.

Influence of Bilateral Subthalamic Nucleus Deep Brain Stimulation on the Lipid Profile in Patients With Parkinson's Disease

Background: Subthalamic nucleus deep brain stimulation (STN-DBS) is a valuable alternative to pharmacotherapy alone in an advanced Parkinson's disease (PD). Given the growing number of patients with STN-DBS, its impact on the comorbidities should be considered.

Aim: The aim of this study was to evaluate the influence of bilateral STN-DBS on the lipid profile in patients with PD.

Methods: Three groups of parkinsonian patients were included: 20 treated pharmacologically–PHT group, 20 newly qualified for STN-DBS–DBS group, and 14 postoperative patients (median 30 months after surgery)–POP group. Plasma concentrations of the total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and body weight were measured thrice in 9 ± 2 month intervals.

Results: A significant increase in the LDL-C concentration is observed early after surgery in the DBS group (11.4 mg/dl, P < 0.01) followed by adverse changes in the HDL-C (−7.7 mg/dl, P = 0.01) and TG (14.1 mg/dl, P = 0.05) plasma levels. In the POP group, the average level of TC at the first visit was significantly higher (P < 0.01) than in the other groups and the TG level was higher than in the PHT group during the follow-up (P < 0.01). A strong positive correlation with body weight alteration after surgery was observed only for long-term changes in the TG levels.

Conclusions: Our data indicate that STN-DBS may negatively affect the cardiometabolic profile of patients. Similarly to body weight gain, an increase in the LDL-C concentration occurred early after surgery while adverse changes in the HDL-C and TG plasma levels were more gradual.

Resting energy expenditure in Parkinson's disease patients under dopaminergic treatment

Background: Weight homeostasis is complex in Parkinson's disease (PD) and body weight changes substantially throughout the course of the disease. We designed a case-control study to (i) investigate whether PD is associated with changes in resting energy expenditure (REE), (ii) to assess how accurately REE could be predicted for individuals with PD utilizing the equations constructed for healthy individuals, and (iii) to eventually construct a new equation.Materials & Methods: Measured REE (mREE) was compared between 122 PD patients and 122 gender and body mass index (BMI)-matched controls. The accuracy of estimated REE by 5 common equations (Harris/Benedict-1919, Roza/Shizgal-1984, Mifflin St. Jeor, WHO/FAO and aggregate formula) was investigated in PD using Bland-Altman analysis and reported as the frequency of accurate predictions (±10%). Concordance correlation coefficients (CCC) were also calculated. Then, we regressed a new REE equation - using gender, age, weight, height and Hoehn-Yahr stage - and validated it in an independent sample (N = 100).Results: No significant difference in mREE was recorded between the whole PD sample and healthy controls. However, mREE was increased in patients with BMI ≥ 30 kg/m² and Hoehn-Yahr stage ≥ 3. Limited accuracy was present in the available REE equations (accurate prediction [±10%] frequency, <60% for all). For the new equation, the proportion of accurate prediction was 67.0% (overestimation, 24.0%) and CCC was 0.77.Conclusion: PD patients are not commonly characterized by an increase in REE. This is limited to patients suffering from obesity and more severe disease. Common REE equations appear to be inaccurate. The new predictive equation proposed in this study provided better REE estimates.

Sarcopenia, dynapenia, and body composition in Parkinson's disease: are they good predictors of disability?: a case-control study

BACKGROUND/AIM

To assess sarcopenia and dynapenia and their relationship with disease severity and disabilities in PD and to state body composition in PD.

METHODS

We conducted a case-control, cross-sectional study that included 70 patients with idiopathic PD and 85 controls. Sarcopenia was defined according to the European Working Group on Sarcopenia in Older People (EWGSOP) criteria. Dynapenia was detected by a handheld dynamometer. Bioimpedance analysis (BIA) was performed, and the SARC-F questionnaire was applied. Disabilities were appointed according to the Katz and Lawton indexes.

RESULTS

Sarcopenia and dynapenia were more prevalent in PD than in controls (50 vs 30.6% and 31.4 vs 17.6%, respectively). Dynapenia was significantly associated with the severity of the disease and disabilities (p = 0.047, p = 0.001); however, sarcopenia was not. The skeletal muscle mass index (SMMI), fat mass index (FMI), and fat-free mass index (FFMI) did not differ between the PD and controls. FMI was lower in the advanced stages of the disease. Higher scores in the SARC-F questionnaire were significantly associated with disabilities and the severity of the disease (p < 0.001, p < 0.001).

CONCLUSION

Muscle strength was closely associated with the severity of the disease and disabilities in PD, but muscle mass was not. Sarcopenia, defined by the SARC-F questionnaire, was a good predictor of disabilities in PD, while the EWGSOP criteria were not. PD patients have a favorable body composition even in advanced stages of the disease with lower FMI and protected lean mass.

The Role of Lipids in Parkinson's Disease

Parkinson’s disease (PD) is a neurodegenerative disease characterized by a progressive loss of dopaminergic neurons from the nigrostriatal pathway, formation of Lewy bodies, and microgliosis. During the past decades multiple cellular pathways have been associated with PD pathology (i.e., oxidative stress, endosomal-lysosomal dysfunction, endoplasmic reticulum stress, and immune response), yet disease-modifying treatments are not available. We have recently used genetic data from familial and sporadic cases in an unbiased approach to build a molecular landscape for PD, revealing lipids as central players in this disease. Here we extensively review the current knowledge concerning the involvement of various subclasses of fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, and lipoproteins in PD pathogenesis. Our review corroborates a central role for most lipid classes, but the available information is fragmented, not always reproducible, and sometimes differs by sex, age or PD etiology of the patients. This hinders drawing firm conclusions about causal or associative effects of dietary lipids or defects in specific steps of lipid metabolism in PD. Future technological advances in lipidomics and additional systematic studies on lipid species from PD patient material may improve this situation and lead to a better appreciation of the significance of lipids for this devastating disease.

Metabolic syndrome and risk of Parkinson disease: A nationwide cohort study

BACKGROUND

The association of metabolic syndrome (MetS) with the development of Parkinson disease (PD) is currently unclear. We sought to determine whether MetS and its components are associated with the risk of incident PD using large-scale cohort data for the whole South Korean population.

METHODS AND FINDINGS

Health checkup data of 17,163,560 individuals aged ≥40 years provided by the National Health Insurance Service (NHIS) of South Korea between January 1, 2009, and December 31, 2012, were included, and participants were followed up until December 31, 2015. The mean follow-up duration was 5.3 years. The hazard ratio (HR) and 95% confidence interval (CI) of PD were estimated using a Cox proportional hazards model adjusted for potential confounders. We identified 44,205 incident PD cases during follow-up. Individuals with MetS (n = 5,848,508) showed an increased risk of PD development compared with individuals without MetS (n = 11,315,052), even after adjusting for potential confounders including age, sex, smoking, alcohol consumption, physical activity, income, body mass index, estimated glomerular filtration rate, and history of stroke (model 3; HR, 95% CI: 1.24, 1.21-1.27). Each MetS component was positively associated with PD risk (HR, 95% CI: 1.13, 1.10-1.16 for abdominal obesity; 1.13, 1.10-1.15 for hypertriglyceridemia; 1.23, 1.20-1.25 for low high-density lipoprotein cholesterol; 1.05, 1.03-1.08 for high blood pressure; 1.21, 1.18-1.23 for hyperglycemia). PD incidence positively correlated with the number of MetS components (log-rank p < 0.001), and we observed a gradual increase in the HR for incident PD with increasing number of components (p < 0.001). A significant interaction between age and MetS on the risk of incident PD was observed (p for interaction < 0.001), and people aged ≥65 years old with MetS showed the highest HR of incident PD of all subgroups compared to those <65 years old without MetS (reference subgroup). Limitations of this study include the possibilities of misdiagnosis of PD and reverse causality.

CONCLUSIONS

Our population-based large-scale cohort study suggests that MetS and its components may be risk factors of PD development.

Conditions Associated with Essential Tremor in Veterans: A Potential Role for Chronic Stress

Background

Increased depression, hearing loss, dementia, alcoholism, and mortality in essential tremor patients remain unexplained. We investigated whether conditions associated with tremor are linked to chronic stress.

Methods

The FY2013 Veterans Affairs database was queried for 38 selected dual diagnosis combinations in 5,854,223 veterans aged 21–95 years.

Results

Post-traumatic stress disorder, anxiety, and depression were the most common psychiatric diagnoses in tremor patients, with the odds ratio exceeding 2 in all 15-year cohorts. Depending on age, patients with essential tremor were more likely than those without to have obsessive–compulsive disorder, bipolar illness, schizophrenia, use tobacco and abuse alcohol, have hypertension, obesity, hyperlipidemia, diabetes, vitamin D deficiency, coronary and cerebrovascular diseases, congestive heart failure, stroke, asthma, hypothyroidism, irritable bowel syndrome, renal insufficiency, alcoholic liver disease, hearing loss, glaucoma, macular degeneration, migraine, epilepsy, idiopathic polyneuropathy, history of head trauma, and ‘Alzheimer’s dementia. In contrast, lung and colorectal cancer, amyotrophic lateral sclerosis, psychostimulant abuse, and rheumatoid arthritis were not more common.

Discussion

Post-traumatic stress disorder, anxiety, and depression, strongly associated with essential tremor, are known risk factors for poor health habits, tobacco use and alcohol abuse; collectively these are risk factors for vascular disease, with further negative health consequences for multiple organ systems. As essential tremor is associated with all these conditions, we propose that chronic stress is not only responsible for the conditions associated with tremor but in some cases itself directly and indirectly induces essential tremor, so that tremor and poor health share a common cause.

Hypertension and Diagnosis of Parkinson's Disease: A Meta-Analysis of Cohort Studies

Background

Hypertension has been associated with cognitive dysfunction in the general population and patients with Alzheimer's disease (AD). However, there are contradictory data regarding the potential association between hypertension and diagnosis of Parkinson's disease (PD), the second most common neurodegenerative disorder after AD. The purpose of this meta-analysis is to synthesize data from cohort studies to explore the potential association between preexisting hypertension and subsequent PD diagnosis.

Methods

The PubMed and Embase databases were searched to identify all relevant studies. Two independent investigators performed the data extraction. Eligible cohort studies providing risk and precision estimates related to hypertension and PD were selected. Pooled risk ratios (RRs) with 95% confidence interval (CI) were calculated by using a random-effects model or a fixed-effects model. Sensitivity analyses after excluding one study at a time were performed to assess the stability of the results. Publication bias was assessed with Begg's test and Egger's test.

Results

Seven cohort studies were identified, including 3,170 persons who were confirmed to have developed PD and 339,517 participants who did not have PD during follow-up. The onset of hypertension before PD diagnosis was significantly associated with an increased risk of motor stage PD (RR = 1.799, 95% CI [1.066-3.037]). This relationship was further confirmed by secondary analyses based on estimates adjusted for potential vascular confounders (RR = 1.319, 95% CI [1.073-1.622]). After excluding one study at a time, the sensitivity analyses still showed that hypertension history was significantly associated with an increased risk of motor stage PD (RR with 95% CI ranging from 1.11 [1.075-1.35] to 1.42 [1.65-1.83]). No publication bias was observed in this meta-analysis.

Conclusion

The findings of this meta-analysis suggest that hypertension may be a risk factor for motor stage PD, which may provide novel insights into the etiology and pathogenesis of this neurodegenerative disorder. However, large-scale well-designed studies that consider various confounders are still needed to further verify and clarify the association between hypertension and PD diagnosis.

Sarcopenia in Parkinson Disease: Comparison of Different Criteria and Association With Disease Severity

OBJECTIVES

In Parkinson disease (PD), sarcopenia may represent the common downstream pathway that from motor and nonmotor symptoms leads to the progressive loss of resilience, frailty, and disability. Here we (1) assessed the prevalence of sarcopenia in older adults with PD using 3 different criteria, testing their agreement, and (2) evaluated the association between PD severity and sarcopenia.

DESIGN

Cross-sectional, observation study.

SETTING

Geriatric day hospital.

PARTICIPANTS

Older adults with idiopathic PD.

MEASUREMENTS

Body composition was evaluated through dual energy x-ray absorptiometry. Handgrip strength and walking speed were measured. Sarcopenia was operationalized according to the Foundation for the National Institutes of Health, the European Working Group on Sarcopenia in Older Persons, and the International Working Group. Cohen k statistics was used to test the agreement among criteria.

RESULTS

Among the 210 participants (mean age 73 years; 38% women), the prevalence of sarcopenia was 28.5%-40.7% in men and 17.5%-32.5% in women. The prevalence of severe sarcopenia was 16.8%-20.0% in men and 11.3%-18.8% in women. The agreement among criteria was poor. The highest agreement was obtained between the European Working Group on Sarcopenia in Older Persons (severe sarcopenia) and International Working Group criteria (k = 0.52 in men; k = 0.65 in women; P < .01 for both). Finally, severe sarcopenia was associated with PD severity (odds ratio 2.30; 95% confidence interval 1.15-4.58).

CONCLUSIONS

Sarcopenia is common in PD, with severe sarcopenia being diagnosed in 1 in every 5 patients with PD. We found a significant disagreement among the 3 criteria evaluated, in detecting sarcopenia more than in ruling it out. Finally, sarcopenia is associated with PD severity. Considering its massive prevalence, further studies should address the prognosis of sarcopenia in PD.

Amnestic dementia impairment in Parkinson's disease: The role of body composition, ageing and insulin resistance

BACKGROUND

The risk of cognitive impairment associated with Parkinson's disease (PD) is related to ageing. The role of body compartmentalization and associated metabolic dysfunctions, as a risk factor for dementia in PD is still not clear.

OBJECTIVE

To investigate body mass distribution, insulin resistance, and other parameters in patients without dementia, and those with dementia classified as compromised delayed memory.

SUBJECTS AND METHODS

We recorded body composition, basal levels of insulin resistance, and other data from 135 patients, who were followed for at least two years. The patients completed a Brief Cognitive Battery test. Patients with delayed recall memory impairment were assessed using the Mattis dementia rating scale.

RESULTS

There was a correlation between age and the patient's scores. Age was negatively correlated with scores on all of the screening battery subtests (p ≤ 0.001), while formal education was positively correlated with the test scores. Insulin resistance was higher in non-demented patients compared to patients with impaired memory (p = 0.0027). There was no association between body composition and cognitive dysfunction in patients with PD.

CONCLUSIONS

The results of this study indicate an apparent decrease in insulin resistance associated with cognitive impairment in PD. We found no correlations between body composition and memory dysfunction associated with PD.

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.

Sarcopenia and Dynapenia in Patients With Parkinsonism

OBJECTIVES

To estimate prevalence of sarcopenia and dynapenia in outpatients with Parkinson disease (PD) and to investigate their association with the features of the disease.

DESIGN

Cross-sectional study.

SETTING

A specialized tertiary care center.

PARTICIPANTS

Consecutive patients (n = 364) aged 65 years or older, affected by parkinsonian syndromes.

MEASUREMENTS

Skeletal muscle mass (SMM), as well as strength and gait speed (GS) were assessed by bioimpedence analysis, handgrip dynamometry, and the 4-meter walking test, respectively. Based on these assessments, sarcopenia was diagnosed using the European Working Group on Sarcopenia in Older People criteria. Dynapenia was defined as handgrip strength less than 30 kg in men and less than 20 kg in women.

RESULTS

In total, 235 patients (64.6%) had a diagnosis of idiopathic PD. Low SMM index was recorded in 27 patients. Due to gait disturbances and postural instability, GS could not be measured in 98 patients and was found to be reduced in 61.3% of those assessed. Prevalence of sarcopenia and dynapenia was 6.6% (95% confidence interval [CI] 4.3-9.7) and 75.5% (95% CI 70.8-79.9), respectively. Sarcopenia tended to be higher in patients unable to perform GS assessment and was unrelated to the type of parkinsonian syndrome. It was associated with older age, longer disease duration, more severe disease, and higher disability in activities of daily living, as assessed by disease-specific clinical rating scale. Dynapenia was directly associated with parkinsonism other than PD, older age, and disability, whereas regular physical therapy appeared to be a preventive factor. However, it was unrelated to disease duration and severity. Finally, the disability score of activities of daily living was inversely correlated with handgrip strength and GS, whereas no association was found with SMM index.

CONCLUSION

Being primarily motor disorders, parkinsonian syndromes are characterized by progressive disability in performing activities of daily living. Impaired functional status is a prominent feature of this patient population, independently of disease duration and severity. Sarcopenia is mainly related to advancing disease and, due to a significant sparing of SMM, is an infrequent condition, likely to play a minor role in disability. Several factors could be responsible for this favorable body composition (eg, motor symptoms, levodopa therapy) and deserve further investigation. The prognostic impact of sarcopenia also needs to be addressed.

The serum lipid profile of Parkinson's disease patients: a study from China

BACKGROUND

The association between the fasting levels of serum lipids and Parkinson's disease (PD) in Chinese populations remains largely unknown.

METHODS

This study enrolled 555 sporadic PD patients and 555 age-, gender- and body mass index (BMI)-matched controls. The fasting serum lipid concentrations of all subjects, including total cholesterol, low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C) and triglycerides (TG), were measured.

RESULTS

Total cholesterol, LDL-C, HDL-C and TG were significantly lower in PD patients than in controls. The prevalence of PD is significantly lower in subjects with the second, third and fourth quartiles of total cholesterol than in those with the first quartile of total cholesterol, regardless of gender. The prevalence of PD is significantly lower in subjects with the third and fourth quartiles of LDL-C than in those with the first quartile of LDL-C, regardless of gender. Negative correlations were found between UPDRS part III score and level of total cholesterol/LDL-C.

CONCLUSIONS

PD patients are with lower levels of total cholesterol, LDL-C, HDL-C and TG than controls. Lipids may be a marker of PD severity.

HDL and cognition in neurodegenerative disorders

High-density lipoproteins (HDLs) are a heterogeneous group of lipoproteins composed of various lipids and proteins. HDL is formed both in the systemic circulation and in the brain. In addition to being a crucial player in the reverse cholesterol transport pathway, HDL possesses a wide range of other functions including anti-oxidation, anti-inflammation, pro-endothelial function, anti-thrombosis, and modulation of immune function. It has been firmly established that high plasma levels of HDL protect against cardiovascular disease. Accumulating evidence indicates that the beneficial role of HDL extends to many other systems including the central nervous system. Cognition is a complex brain function that includes all aspects of perception, thought, and memory. Cognitive function often declines during aging and this decline manifests as cognitive impairment/dementia in age-related and progressive neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. A growing concern is that no effective therapy is currently available to prevent or treat these devastating diseases. Emerging evidence suggests that HDL may play a pivotal role in preserving cognitive function under normal and pathological conditions. This review attempts to summarize recent genetic, clinical and experimental evidence for the impact of HDL on cognition in aging and in neurodegenerative disorders as well as the potential of HDL-enhancing approaches to improve cognitive function.

Weight gain and increased central obesity in the early phase of Parkinson's disease

BACKGROUND & AIMS

Weight loss is strongly associated with Parkinson's disease (PD) and impacts symptoms and disease progression. The aim of this study was to describe changes in body composition and to explore how body weight (BW), relates to disease progression and medication in the early phase of PD.

METHODS

Participants in a prospective community-based case-control study of PD were followed-up three years after initial diagnosis. Anthropometric and bioelectrical impedance spectroscopy (BIS) measurements were used together with Mini Nutritional Assessment (MNA), a 24-h recall (24-HR) and a 3-day food registration (3-DFR) to complete the evaluation of nutritional status. Disease severity was assessed using the Mini Mental State Examination (MMSE), the Unified Parkinson's Disease Rating Scale motor score (UPDRS III), and the Hoehn and Yahr rating.

RESULTS

The PD patients' BW gained 1.62 kg (±4.60, P = 0.009), an increase that significantly correlated with fat mass (FM) (r = 0.74), waist size (r = 0.65), waist/height ratio (r = 0.64), and total skin fold (r = 0.77). Linear regression showed an association between change in BW and physical activity level (PAL) (B = -8.554; P = 0.025) confirmed by the multiple linear regression. Linear regression also revealed an association between change in FM and MMSE (B = 0.654; P = 0.027).

CONCLUSION

In early PD, weight gain was revealed over three years accompanied by an increase in FM and waist circumference. An inverse relation was revealed between change in BW and PAL. The MMSE, UPDRS III, and Hoehn and Yahr rating were unchanged. Medication and swallowing difficulties were not associated with change in BW.

Parkinson's disease and the cardio-ankle vascular stiffness index

OBJECTIVE

To investigate the relationship between Parkinson's disease (PD) and the cardio-ankle vascular stiffness index (CAVI), a novel non-invasive measurement of vascular stiffness.

METHODS

A total of 63 PD subjects who underwent CAVI measurement were enrolled, including 30 men and 33 women 69.1±7.5 years of age (range: 46-79 years). Sixty-three non-PD subjects (30 men, 33 women, mean age: 68.7±7.6 years [range: 43-79 years]) served as controls. Comparisons between the control and PD subjects were made using Fisher's protected least significant difference, the Bonferroni-Dunn test, Scheffe's test and the unpaired t-test.

RESULTS

1) The average CAVI values were as follows: control, 9.3±0.9; PD, 9.0±1.0 (p=0.049). The differences in the CAVI values between the groups and the index values (normative data provided internally in the VaSera system) were as follows: control, 0.4±0.8; PD, 0.03±0.9 (p=0.011). The CAVI values of the PD patients were significantly smaller than those of the control subjects. 2) Among the control subjects, the CAVI values in the subjects with atherosclerotic risk factors (hypertension, dyslipidemia and/or diabetes) were significantly higher than those observed in the subjects without risk factors. In contrast, among the PD patients, the CAVI values in the subjects with atherosclerotic risk factors were equivalent to those observed in the subjects without risk factors. 3) Among the PD patients, the CAVI values did not change with the motor stage.

CONCLUSION

The results of the present study show that, compared with control subjects, PD patients exhibit normal CAVI values despite having mild but significant atherosclerotic risk factors, e.g., hypertension and diabetes. These findings suggest that PD patients are less vulnerable to systemic atherosclerosis than their risk factors may suggest.

Cardiometabolic factors and disease duration in patients with Parkinson's disease

OBJECTIVE

Previous studies have reported that patients with Parkinson's disease (PD) have a favorable cardiometabolic risk profile. The aim of this study was to investigate the relationship between cardiometabolic risk factors and the duration of disease.

METHODS

One hundred and fifty patients with PD (56.7% men) were studied, measuring body mass index (BMI), waist circumference (WC), body fat percentage (BF%) by impedance, fasting glucose, serum lipids, and transaminases.

RESULTS

In sex- and age-adjusted correlation models, duration of PD was inversely related to BMI (r = -0.20; P < 0.05) and BF% (r = -0.29; P < 0.005). Using multivariable regression models (adjustments: age, gender, smoking status, levodopa dose and, alternatively, BMI, WC, or BF%), high-density lipoprotein (HDL) levels were positively correlated with disease duration (P < 0.01 for all). In models adjusted for WC and BF%, total HDL-cholesterol ratio was also inversely associated with duration of PD (P < 0.05 for both). No other association between biochemical variables and the duration of PD was found. Moreover, no dose-response effect of levodopa on metabolic risk factors was observed.

CONCLUSIONS

HDL levels and total HDL-cholesterol ratio were favorably associated with duration of PD. This factor may contribute to cardiometabolic protection in PD. The mechanisms underlying this association deserve further investigation.

Multicentre analysis of 178,992 type 2 diabetes patients revealed better metabolic control despite higher rates of hypertension, stroke, dementia and repeated inpatient care in patients with comorbid Parkinson's disease

BACKGROUND

Especially in older people, physicians are faced with the coexistence of type 2 diabetes mellitus (T2DM) and Parkinson's disease (PD). Therefore, this research aimed to compare diabetes endpoints between T2DM with and without PD.

METHODS

Based on the standardized, multicenter, prospective DPV database, 178,992 T2DM patients (≥40 years) were analyzed. 1579 were diagnosed with PD and/or received specific treatment. Hierarchical multivariable regression models were used for group comparisons; adjusted estimates based on observed marginal frequencies were calculated.

RESULTS

PD patients were significantly older (77.9 vs. 70.0 years; p < 0.0001) and had a longer diabetes duration (10.3 vs. 8.4 years; p < 0.0001). In young PD patients (<50 years), percentage of females was significantly higher compared to age-matched T2DM patients without PD or people of the German population (66.7 vs. 38.1 vs. 49.0%; p < 0.0001, p < 0.02). After demographic adjustment, T2DM patients with PD showed a significantly lower HbA1c (58.0 vs. 60.3 mmol/mol; p < 0.0001), OAD/GLP-1 treatment (41.9 vs. 45.9%; p < 0.01) and frequency of dyslipidemia (62.0 vs. 64.5%; p < 0.05). In contrast, rates of insulin therapy (57.8 vs. 54.8%; p < 0.05), hypertension (73.3 vs. 68.6%; p < 0.001), antihypertensive medication (60.4 vs. 56.1%; p < 0.01), stroke (12.0 vs. 7.3%; p < 0.0001), dementia (9.2 vs. 2.6%; p < 0.0001) and repeated inpatient care (15.7 vs. 12.0%; p < 0.0001) were significantly higher and duration of hospital stay (6.2 vs. 4.7 days; p < 0.0001) was significantly longer in T2DM with PD.

CONCLUSION

Clear demographic and clinical differences were observed between T2DM with and without PD. In PD patients, metabolic control is better, potentially due to more intensive medical care.

Nutritional risk and gastrointestinal dysautonomia symptoms in Parkinson's disease outpatients hospitalised on a scheduled basis

Dysautonomia symptoms of nutritional interest may often occur in Parkinson's disease (PD), but the role played in affecting the risk of malnutrition still needs to be clarified. A total of 208 consecutive PD outpatients hospitalised on a scheduled basis were assessed for nutritional risk by the Malnutrition Universal Screening Tool. Presence of dysautonomia symptoms (dysphagia, sialorrhoea and constipation) was investigated using clinical rating scales. In our population, prevalence of nutritional risk was 17·2 (95 % CI 12·1, 24·0) % and relied mainly on unintentional weight loss. Sialorrhoea, dysphagia, dysphagia to liquids and constipation were observed in 10·6, 11·0, 14·4 and 59·6 % of the patients, respectively. Nutritional risk was independently associated with the number of dysautonomia symptoms (OR 1·39 (95 % CI 1·00, 1·96); P= 0·048) but not with single symptoms. An independent association was also found with the severity of motor symptoms (Hoehn-Yahr stage, OR 1·48 (95 % CI 1·00, 2·55); P= 0·049) and levodopa dose (OR 1·16 (95 % CI 1·04, 1·31) mg/kg per d; P= 0·009). Nutritional risk in PD outpatients appears to depend mainly on dysautonomic syndrome, disease severity and levodopa dosage. Implications for outcome deserve further investigation. The assessment of nutritional status and of gastrointestinal dysautonomia symptoms should be part of the routine work-up of a PD patient.