Trends in Mortality From Parkinson Disease in the United States, 1999-2019

Temporal trends in Parkinson's disease among older adults in the United States from 1999 to 2020: Retrospective analysis from CDC WONDER database

This retrospective study assessed the mortality trends related to Parkinson's Disease (PD) between 1999 and 2020. We assessed individuals aged 65 years and older and a total of 831,793 deaths were identified. Of these total number of deaths, place of death was accessible for 830,176 cases. Majority of the deaths occurred in nursing homes of long-term care facilities (367,633), followed by at home (212,886), medical facilities (165,450), other locations (44,506), and hospice (39,701). Analysis of age-adjusted mortality rates (AAMR) revealed an overall rise from 1999 to 2020, 88.9 to 119.6 per 100,000 population. AAMR showed an initial decline between 1999 and 2013, followed by a slight increase between 2013 and 2018 and then a significant rise from 2018 to 2020. Gender-based analysis showed a constantly higher AAMR for older men compared to older women. Variations in AAMR based on race and ethnicity revealed that Non-Hispanic White population had the highest AAMRs. Geographic disparities among states showed that Nebraska, Vermont, Minnesota, Utah, and Idaho had a significantly higher AAMR than Hawaii, Florida, Nevada. New York, and District of Columbia. Midwest region had a consistently higher AAMR followed by West, South, and Northeast. Additionally, nonmetropolitan areas had a higher AAMR than metropolitan areas. These findings offer valuable insights into mortality patterns related to PD among the elderly, highlighting the significance of incorporating demographic and geographic variables into public health planning and interventions.

Trends of mortality from epilepsy in the United States, 1979-2021

PURPOSE

The analysis of long-term trends of mortality from epilepsy has not been conducted, which is crucial for estimating the future burden of epilepsy. We therefore aimed to investigate the long-term trends of mortality from epilepsy in the United States from 1979 to 2021.

METHODS

The cause-of-death and demographic data were from the National Center for Health Statistics (1979-2021) and population estimates were from the US Census Bureau. We used the joinpoint regression model to analyze secular trends in the mortality of epilepsy spanning from 1979 to 2021. Age-adjusted mortality from epilepsy was assessed based on the year 2000 U.S. population data, stratified by age, sex, and race.

RESULTS

The age-adjusted mortality from epilepsy increased from 0.78 per 100,000 population in 1979 to 1.01 per 100,000 population in 2021, with an average annual percent change (AAPC) of 0.58% (95% confidence interval [CI]: 0.45% - 0.72%). The overall age-adjusted mortality of epilepsy had been on the rise between 2011 and 2021. The mortality rate generally increases with age. The mortality of epilepsy was higher in the Afro-American people and men. The mortality of epilepsy in both sexes declined first and then increased, with AAPC 1.02% (95% CI: 0.88%, 1.23%) in women and 0.10% (95% CI: -0.002%, 0.21%) in men. Mortality in all races including White, Afro-American people, and other races individuals fell first and then rose. The AAPC of mortality in White, other races, and Afro-American people were 0.89% (95% CI: 0.79%, 1.02%), -0.87% (95% CI: -1.84%, 0.88%), and -0.31% (95% CI: -0.48%, -0.13%), respectively.

CONCLUSION

Although the mortality rate from epilepsy has experienced a period of decline, it is worth noting that the last decade has seen a rapid increase. A comprehensive assessment of long-term trends in mortality from epilepsy holds significance for healthcare prioritization.

Association between Parkinson's disease and cardiovascular disease mortality: a prospective population-based study from NHANES

BACKGROUND AND AIM

Conflicting results have been reported on the association between Parkinson's disease (PD) and cardiovascular disease (CVD) mortality in different populations. Therefore, studying the relationship between PD and CVD mortality is crucial to reduce mortality caused by the former.

METHODS

In this cohort investigation, we enrolled 28,242 participants from the National Health and Nutrition Examination Survey spanning from 2003 to 2018. The 380 cases of PD in the cohort were identified by documenting 'ANTIPARKINSON AGENTS' in their reported prescription medications. Mortality outcomes were ascertained by cross-referencing the cohort database with the National Death Index, which was last updated on 31 December 2019. Cardiovascular disease mortality was categorised according to the 10th revision of the International Classification of Diseases by using a spectrum of diagnostic codes. Weighted multivariable Cox regression analysis was used to examine the association between PD and the risk of CVD mortality.

RESULTS

A total of 28,242 adults were included in the study [mean age, 60.156 (12.55) years, 13,766 men (48.74%)], and the median follow-up period was 89 months. Individuals with PD had an adjusted HR of 1.82 (95% CI, 1.24-2.69; p = 0.002) for CVD mortality and 1.84 (95% CI, 1.44-2.33; p < 0.001) for all-cause mortality compared with those without PD. The association between PD and CVD mortality was robust in sensitivity analyses, after excluding participants who died within 2 years of follow-up and those with a history of cancer at baseline [HR,1.82 (95% CI, 1.20-2.75; p = 0.005)].

CONCLUSIONS

PD was associated with a high long-term CVD mortality rate in the US population.

Retrospective analyses evaluating the mortality risk associated with pimavanserin or other atypical antipsychotics in patients with Parkinson disease psychosis

Introduction

Parkinson's disease (PD) is associated with increased mortality risk (MR), reflecting progression of motor and nonmotor symptoms. PD psychosis (PDP), a common nonmotor symptom, increases with prolonged disease and elevates the MR of PD even further. Pimavanserin is the only FDA-approved treatment for PDP. This review summarizes real-world evidence around the MR of patients with PDP treated with pimavanserin versus off-label atypical antipsychotics.

Methods

A PubMed search was conducted using the following search terms: pimavanserin AND antipsychotic AND mortality AND Parkinson's disease AND psychosis. Inclusion criteria specified the entry of retrospective, observational, and open-label studies comparing pimavanserin to atypical antipsychotics or untreated controls.

Results

A total of 10 of the 32 articles met inclusion criteria. Among five comparisons of pimavanserin with atypical antipsychotics, two were large (n = 21,719; n = 21,975), representative, Medicare-database studies, which demonstrated comparable or lower all-cause pimavanserin MR. Among three pimavanserin versus control studies, two reported lower or comparable pimavanserin MR and one, long-term care study reported higher MR for pimavanserin versus non-pimavanserin treated patients with unknown PDP status. Two open-label extensions reported pimavanserin mortality rates of 6.45 and 18.8 deaths per 100 patient-years, which are comparable to, or lower than, mortality rates for PD, PDP, and other atypical antipsychotics. Most studies (70 %; 7 of 10) demonstrated pimavanserin's MR was lower than or similar to other atypical antipsychotics or untreated controls.

Conclusions

Pimavanserin did not increase the MR in PDP. Pimavanserin's MR appears to be comparable to or lower than other atypical antipsychotics prescribed for PDP, including quetiapine.

Trends in parkinson's disease mortality in China from 2004 to 2021: a joinpoint analysis

BACKGROUND

This study aimed to analyze the trends of Parkinson's disease (PD) mortality rates among Chinese residents from 2004 to 2021, provide evidence for the formulation of PD prevention and control strategies to improve the quality of life among PD residents.

METHODS

Demographic and sociological data such as gender, urban or rural residency and age were obtained from the National Cause of Death Surveillance Dataset from 2004 to 2021. We then analyzed the trends of PD mortality rates by Joinpoint regression.

RESULTS

The PD mortality and standardized mortality rates in China showed an overall increasing trend during 2004-2021 (average annual percentage change [AAPC] = 7.14%, AAPCASMR=3.21%, P < 0.001). The mortality and standardized mortality rate in male (AAPC = 7.65%, AAPCASMR=3.18%, P < 0.001) were higher than that of female (AAPC = 7.03%, AAPCASMR=3.09%, P < 0.001). The PD standardized mortality rates of urban (AAPC = 5.13%, AAPCASMR=1.76%, P < 0.001) and rural (AAPC = 8.40%, AAPCASMR=4.29%, P < 0.001) residents both increased gradually. In the age analysis, the mortality rate increased with age. And the mortality rates of those aged > 85 years was the highest. Considering gender, female aged > 85 years had the fastest mortality trend (annual percentage change [APC] = 5.69%, P < 0.001). Considering urban/rural, rural aged 80-84 years had the fastest mortality trend (APC = 6.68%, P < 0.001).

CONCLUSIONS

The mortality rate of PD among Chinese residents increased from 2004 to 2021. Male sex, urban residence and age > 85 years were risk factors for PD-related death and should be the primary focus for PD prevention.

The Potentiality of Natural Products and Herbal Medicine as Novel Medications for Parkinson's Disease: A Promising Therapeutic Approach

As the global population ages, the prevalence of Parkinson's disease (PD) is steadily on the rise. PD demonstrates chronic and progressive characteristics, and many cases can transition into dementia. This increases societal and economic burdens, emphasizing the need to find effective treatments. Among the widely recognized causes of PD is the abnormal accumulation of proteins, and autophagy dysfunction accelerates this accumulation. The resultant Lewy bodies are also commonly found in Alzheimer's disease patients, suggesting an increased potential for the onset of dementia. Additionally, the production of free radicals due to mitochondrial dysfunction contributes to neuronal damage and degeneration. The activation of astrocytes and the M1 phenotype of microglia promote damage to dopamine neurons. The drugs currently used for PD only delay the clinical progression and exacerbation of the disease without targeting its root cause, and come with various side effects. Thus, there is a demand for treatments with fewer side effects, with much potential offered by natural products. In this study, we reviewed a total of 14 articles related to herbal medicines and natural products and investigated their relevance to possible PD treatment. The results showed that the reviewed herbal medicines and natural products are effective against lysosomal disorder, mitochondrial dysfunction, and inflammation, key mechanisms underlying PD. Therefore, natural products and herbal medicines can reduce neurotoxicity and might improve both motor and non-motor symptoms associated with PD. Furthermore, these products, with their multi-target effects, enhance bioavailability, inhibit antibiotic resistance, and might additionally eliminate side effects, making them good alternative therapies for PD treatment.

Nanowired delivery of antibodies to tau and neuronal nitric oxide synthase together with cerebrolysin attenuates traumatic brain injury induced exacerbation of brain pathology in Parkinson's disease

Concussive head injury (CHI) is one of the major risk factors for developing Parkinson's disease in later life of military personnel affecting lifetime functional and cognitive disturbances. Till date no suitable therapies are available to attenuate CHI or PD induced brain pathology. Thus, further exploration of novel therapeutic agents are highly warranted using nanomedicine in enhancing the quality of life of veterans or service members of US military. Since PD or CHI induces oxidative stress and perturbs neurotrophic factors regulation associated with phosphorylated tau (p-tau) deposition, a possibility exists that nanodelivery of agents that could enhance neurotrophic factors balance and attenuate oxidative stress could be neuroprotective in nature. In this review, nanowired delivery of cerebrolysin-a balanced composition of several neurotrophic factors and active peptide fragments together with monoclonal antibodies to neuronal nitric oxide synthase (nNOS) with p-tau antibodies was examined in PD following CHI in model experiments. Our results suggest that combined administration of nanowired antibodies to nNOS and p-tau together with cerebrolysin significantly attenuated CHI induced exacerbation of PD brain pathology. This combined treatment also has beneficial effects in CHI or PD alone, not reported earlier.

The nonsynaptic plasticity in Parkinson's disease: Insights from an animal model

BACKGROUND

The 6-OHDA nigro-striatal lesion model has already been related to disorders in the excitability and synchronicity of neural networks and variation in the expression of transmembrane proteins that control intra and extracellular ionic concentrations, such as cation-chloride cotransporters (NKCC1 and KCC2) and Na+/K+-ATPase and, also, to the glial proliferation after injury. All these non-synaptic mechanisms have already been related to neuronal injury and hyper-synchronism processes.

OBJECTIVE

The main objective of this study is to verify whether mechanisms not directly related to synaptic neurotransmission could be involved in the modulation of nigrostriatal pathways.

METHODS

Male Wistar rats, 3 months old, were submitted to a unilateral injection of 24 µg of 6-OHDA, in the striatum (n = 8). The animals in the Control group (n = 8) were submitted to the same protocol, with the replacement of 6-OHDA by 0.9% saline. The analysis by optical densitometry was performed to quantify the immunoreactivity intensity of GFAP, NKCC1, KCC2, Na+/K+-ATPase, TH and Cx36.

RESULTS

The 6-OHDA induced lesions in the striatum, were not followed by changes in the expression cation-chloride cotransporters and Na+/K+-ATPase, but with astrocytic reactivity in the lesioned and adjacent regions of the nigrostriatal. Moreover, the dopaminergic degeneration caused by 6-OHDA is followed by changes in the expression of connexin-36.

CONCLUSIONS

The use of the GJ blockers directly along the nigrostriatal pathways to control PD motor symptoms is conjectured. Electrophysiology of the striatum and the substantia nigra, to verify changes in neuronal synchronism, comparing brain slices of control animals and experimental models of PD, is needed.

Mortality rates for Parkinson's disease are increasing in Spain. An Age-Period-Cohort and Joinpoint Analysis in Mortality Rates from 1981 to 2020

BACKGROUND

Mortality in Parkinson's disease is increasing worldwide, but Spanish data need further study.

OBJECTIVE

To analyse the mortality trends of Parkinson's disease in Spain between 1981 and 2020.

METHODS

This observational retrospective study assessed the Parkinson's disease mortality data from 1981 to 2020 were collected from the National Statistics Institute of Spain. Age-standardized mortality rates were analysed by age and sex groups, detecting significant mortality trends through a joinpoint analysis. Age-period-cohort effect and potential years of life lost analyses were conducted. The European standard population of 2013 was considered for the analyses.

RESULTS

A total of 88,034 deaths were assessed. The overall age-standardized mortality rate rose throughout the period from 3.67 to 8.57 per 100,000 inhabitants. Mortality rates in men were higher than in women, 11.63 versus 6.57 deaths per 100,000 inhabitants. The sex ratio showed an increase in premature mortality in men during 2020. The overall joinpoint analysis recorded a rise in mortality, primarily since the twentieth century, mainly in male and older groups, that matched with a period effect. The age effect was detected, confirming higher mortality at an older age. The analysis of potential years of life lost detected a growth in this rate, changing from 0.66 in 1981 to 1.06 in 2020.

CONCLUSIONS

Mortality data for Parkinson's disease in Spain rose significantly in forty years. Mortality rate was higher in the male and age group above 75 years of age. The sex ratio showed premature mortality in men in 2020, which will need further study.

Orexin pathway in Parkinson's disease: a review

Parkinson's disease (PD) is a progressive neurodegenerative disease (NDD) caused by dopaminergic neuron degeneration in the substantia nigra (SN). Orexin is a neuropeptide that plays a role in the pathogenesis of PD. Orexin has neuroprotective properties in dopaminergic neurons. In PD neuropathology, there is also degeneration of orexinergic neurons in the hypothalamus, in addition to dopaminergic neurons. However, the loss of orexinergic neurons in PD began after the degeneration of dopaminergic neurons. Reduced activity of orexinergic neurons has been linked to developing and progressing motor and non-motor symptoms in PD. In addition, the dysregulation of the orexin pathway is linked to the development of sleep disorders. The hypothalamic orexin pathway regulates various aspects of PD neuropathology at the cellular, subcellular, and molecular levels. Finally, non-motor symptoms, particularly insomnia and disturbed sleep, promote neuroinflammation and the accumulation of neurotoxic proteins as a result of defects in autophagy, endoplasmic reticulum (ER) stress, and the glymphatic system. As a result, this review aimed to highlight the potential role of orexin in PD neuropathology.

Quivering hand and heart: Parkinson's disease is not associated with increased in-hospital mortality in atrial fibrillation hospitalizations: A nationwide analysis

Background

Autonomic dysfunction in Parkinson's disease (PD) includes cardiovascular dysregulations which may manifest as an increased risk of atrial fibrillation (AF). However, data on the impact of PD in AF patients is lacking. Our study aimed to investigate the differences in in-hospital mortality of patients admitted for AF with underlying PD versus those without PD.

Methods

We examined the National Inpatient Sample (NIS) database from 2016 to 2019 for hospitalizations of AF as a principal diagnosis with and without PD as a secondary diagnosis. The primary outcome was inpatient mortality. The secondary endpoints were ventricular tachycardia (VT), ventricular fibrillation (VF), acute heart failure (AHF), cardiogenic shock (CS), cardiac arrest (CA), total hospital charge (THC), and length of stay (LOS).

Results

Of 1,861,859 A F hospitalizations, 0.01% (19,490) had coexisting PD. Cohorts of PD vs No-PD had a mean age of 78.1 years [CI 77.9-78.4] vs 70.5 years [CI 70.4-70.5]; male (56.3% vs 50.7%), female (43.7% vs 49.3%). The PD category had similar in-hospital mortality with the no-PD category (OR_Adj = 1.18 [0.89-1.57] P = 0.240). The PD group had a lesser incidence of AHF (OR_Adj = 0.79 [0.72-0.86] P < 0.001) and VT (OR_Adj = 0.77 [0.62-0.95] P = 0.015).

Conclusion

Co-existing PD in patients admitted for AF was not associated with increased in-hospital mortality; however, there were lower odds of AHF and VT. The diminished arrhythmogenic neurohormonal axis may explain these cardiovascular benefits. Notwithstanding, to better understand the outcomes of AF in patients with PD, additional studies are required.

Cytosolic DNA sensors and glial responses to endogenous DNA

Genomic instability is a key driving force for the development and progression of many neurodegenerative diseases and central nervous system (CNS) cancers. The initiation of DNA damage responses is a critical step in maintaining genomic integrity and preventing such diseases. However, the absence of these responses or their inability to repair genomic or mitochondrial DNA damage resulting from insults, including ionizing radiation or oxidative stress, can lead to an accumulation of self-DNA in the cytoplasm. Resident CNS cells, such as astrocytes and microglia, are known to produce critical immune mediators following CNS infection due to the recognition of pathogen and damage-associated molecular patterns by specialized pattern recognition receptors (PRRs). Recently, multiple intracellular PRRs, including cyclic GMP-AMP synthase, interferon gamma-inducible 16, absent in melanoma 2, and Z-DNA binding protein, have been identified as cytosolic DNA sensors and to play critical roles in glial immune responses to infectious agents. Intriguingly, these nucleic acid sensors have recently been shown to recognize endogenous DNA and trigger immune responses in peripheral cell types. In the present review, we discuss the available evidence that cytosolic DNA sensors are expressed by resident CNS cells and can mediate their responses to the presence of self-DNA. Furthermore, we discuss the potential for glial DNA sensor-mediated responses to provide protection against tumorigenesis versus the initiation of potentially detrimental neuroinflammation that could initiate or foster the development of neurodegenerative disorders. Determining the mechanisms that underlie the detection of cytosolic DNA by glia and the relative role of each pathway in the context of specific CNS disorders and their stages may prove pivotal in our understanding of the pathogenesis of such conditions and might be leveraged to develop new treatment modalities.

Trends and Sex Differences in Hospitalizations and Mortality in Parkinson's Disease in Spain (2010-2019): A Nationwide Population-Based Study

The incidence of hospitalizations of Parkinson´s disease (PD) in Spain suffered a steady rise from 1997 to 2012. However, data on the trends during the following decade (2010-2019) are lacking. Hospital admissions with a primary and secondary diagnosis of PD were selected using the Spanish National Hospital Discharge Database (SNHDD) for the period 2010-2019. The primary endpoint was the incidence of hospitalizations and in-hospital mortality, stratified in biannual periods. The incidence of PD hospitalizations increased progressively over time from 81.25 cases in 2010-2011 to 94.82 cases in 2018-2019 per 100,000 inhabitants. Male sex, age and comorbidity also increased progressively in PD inpatients. PD as a comorbid condition presented a higher increment (annual percentage of change, APC +1.71%, p < 0.05) than PD as the main reason of hospitalization (APC +1.26%, p < 0.05). In the multivariate regression model, factors associated with mortality were male sex (OR = 1.15, 95% CI 1.01-1.35), age (>80 years, OR = 12.76, 95% CI 3.96-29.64) and comorbidity (Charlson index ≥ 2, OR 1.77, 95% CI 1.69-1.85). Adjusted mortality by age, sex, comorbidity and diagnostic position remained stable. In conclusion, PD hospitalizations in Spain have increased, with a parallel increment in mean age, male sex and higher comorbidities. However, adjusted mortality remains unchanged. The burden of this disease may increase the complexity and costs of hospital care in the future.

Current Status and Future Perspectives on Stem Cell-Based Therapies for Parkinson's Disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting 1%-2% of the population over the age of 65. As the population ages, it is anticipated that the burden on society will significantly escalate. Although symptom reduction by currently available pharmacological and/or surgical treatments improves the quality of life of many PD patients, there are no treatments that can slow down, halt, or reverse disease progression. Because the loss of a specific cell type, midbrain dopamine neurons in the substantia nigra, is the main cause of motor dysfunction in PD, it is considered a promising target for cell replacement therapy. Indeed, numerous preclinical and clinical studies using fetal cell transplantation have provided proof of concept that cell replacement therapy may be a viable therapeutic approach for PD. However, the use of human fetal cells remains fraught with controversy due to fundamental ethical, practical, and clinical limitations. Groundbreaking work on human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, coupled with extensive basic research in the stem cell field offers promising potential for hPSC-based cell replacement to become a realistic treatment regimen for PD once several major issues can be successfully addressed. In this review, we will discuss the prospects and challenges of hPSC-based cell therapy for PD.

Worldwide trends in mortality related to Parkinson's disease in the period of 1994–2019: Analysis of vital registration data from the WHO Mortality Database

Background

Mortality due to Parkinson's disease (PD) and its long-term trends worldwide in recent decades remain unknown. No previous studies have simultaneously studied age- and sex-specific mortality trends at a population level worldwide. Insights gained from this study can help identify high-risk populations and inform healthcare service requirements for managing Parkinson's disease globally.

Objectives

The aim of the study was to examine trends in mortality from Parkinson's disease by age-group and sex across countries all over the world. In this study, we used worldwide registry data to examine the temporal trends in PD mortality across most counties of the world from 1994 to 2019 using joinpoint regression.

Results

In data from vital registration systems, huge variations in the patterns of deaths due to Parkinson's disease were observed both over time and between countries. Between 1994 and 2019, there was a significant increase in mortality rates globally in both men and women. In more detail, the mortality rate (per 100,000) in 1994 was 1.76 and reached 5.67 in 2019. Greater increases in mortality were seen in men than in women; and in older than in younger people.

Conclusions

There has been a striking rising trend in Parkinson's disease mortality globally. Persistent age and sex disparities are found in Parkinson's disease mortality trends. Our findings may have important implications for future research, healthcare planning, and provision.

Long-term exposure to particulate air pollution and incidence of Parkinson's disease: A nationwide population-based cohort study in South Korea

There has been increasing interest in the neurological impact of particulate matter (PM). However, its association with the incidence of Parkinson's disease (PD) remains unclear. We selected 313,355 participants satisfying inclusion criteria from the National Health Insurance Service-National Sample Cohort based on the nationwide population of South Korea, and followed them up from January 2007 through December 2015. Individual-level long-term PM exposure was assessed as the five time-varying average concentrations estimated for the previous 1, 2, 3, 4 and 5 years on each year (until censored or event occurred) at the district-level residential addresses of participants using a previously validated prediction model. Incident PD was defined as the first diagnosis accompanied by anti-PD medication prescription from 2007 through 2015. Time-varying Cox proportional hazards models were employed to estimate the hazard ratio (HR) of incident PD for long-term PM exposure, adjusting for individual- and area-level covariates. During the 8 years (2,745,389 person-years) of follow-up for a total of 313,355 participants (mean [range] age, 48.9 [19-87] years; 169,571 males [54.1%]), 2621 participants (0.8%) developed PD. The HR of incident PD per interquartile range (3.3 μg/m³) increase in fine PM (PM_2.5) for the previous 1 year was 1.08 (95% confidence interval: 1.01-1.19). In subgroup-specific analyses, HRs for PM_2.5 were significant among older participants, males, participants living in metropolitan cities, ibuprofen users, and participants with comorbidities (HR: 1.10-1.20). Long-term exposure to PM_2.5 might play a role in PD development.

Gut Microbiota: A Novel Therapeutic Target for Parkinson’s Disease

Parkinson’s disease (PD) is the second most common neurodegenerative disease characterized by motor dysfunction. Growing evidence has demonstrated that gut dysbiosis is involved in the occurrence, development and progression of PD. Numerous clinical trials have identified the characteristics of the changed gut microbiota profiles, and preclinical studies in PD animal models have indicated that gut dysbiosis can influence the progression and onset of PD via increasing intestinal permeability, aggravating neuroinflammation, aggregating abnormal levels of α-synuclein fibrils, increasing oxidative stress, and decreasing neurotransmitter production. The gut microbiota can be considered promising diagnostic and therapeutic targets for PD, which can be regulated by probiotics, psychobiotics, prebiotics, synbiotics, postbiotics, fecal microbiota transplantation, diet modifications, and Chinese medicine. This review summarizes the recent studies in PD-associated gut microbiota profiles and functions, the potential roles, and mechanisms of gut microbiota in PD, and gut microbiota-targeted interventions for PD. Deciphering the underlying roles and mechanisms of the PD-associated gut microbiota will help interpret the pathogenesis of PD from new perspectives and elucidate novel therapeutic strategies for PD.

Mortality of Parkinson's disease in Italy from 1980 to 2015

OBJECTIVE

To evaluate mortality for Parkinson's disease (PD) in Italy during a long time period (1980-2015) and to discuss the role of possible general and specific influencing factors.

METHODS

Based on mortality data provided by the Italian National Institute of Statistics, sex- and age-specific crude mortality rates were computed, for the whole country and for its main geographical sub-areas. Rates were standardized using both direct (annual mortality rates AMRs) and indirect (standardized mortality rates SMRs) methods. SMRs were used to evaluate geographical differences, whereas AMRs and joinpoint linear regression analysis to study mortality trends.

RESULTS

Considering the entire period, highest mortality rates were observed in males (AMR/100,000: 9.0 in males, 5.25 in females), in North-West and Central Italy (SMR > 100). Overall PD mortality decreased from mid-eighties onwards and then rapidly reversed the trend in the period 1998-2002, rising up to a maximum in 2015, with some differences according to sex and geographical areas.

CONCLUSIONS

Several factors may have contributed to the rapid inversion of decreasing trend in mortality observed in the last part of XX century. Possible explanations of this rising trend are related to the increasing burden of PD (especially in males and in certain Italian regions), caused by different factors as population aging, physiological prevalence rise due to incidence exceeding mortality, and growing exposure to environmental or occupational risk factors. In addition, the accuracy of death certificate compilation could account for geographical differences and for the temporal trend. The role of levodopa and recently introduced dopaminergic drugs is also discussed.

Exploring the Causal Effect of Constipation on Parkinson’s Disease Through Mediation Analysis of Microbial Data

Background and Aims

Parkinson’s disease (PD) is a worldwide neurodegenerative disease with an increasing global burden, while constipation is an important risk factor for PD. The gastrointestinal tract had been proposed as the origin of PD in Braak’s gut–brain axis hypothesis, and there is increasing evidence indicating that intestinal microbial alteration has a role in the pathogenesis of PD. In this study, we aim to investigate the role of intestinal microbial alteration in the mechanism of constipation-related PD.

Methods

We adapted our data from Hill‐Burns et al., in which 324 participants were enrolled in the study. The 16S rRNA gene sequence data were processed, aligned, and categorized using DADA2. Mediation analysis was used to test and quantify the extent by which the intestinal microbial alteration explains the causal effect of constipation on PD incidence.

Results

We found 18 bacterial genera and 7 species significantly different between groups of constipated and non-constipated subjects. Among these bacteria, nine genera and four species had a significant mediation effect between constipation and PD. All of them were short-chain fatty acid (SCFA)-producing bacteria that were substantially related to PD. Results from the mediation analysis showed that up to 76.56% of the effect of constipation on PD was mediated through intestinal microbial alteration.

Conclusion

Our findings support that gut dysbiosis plays a critical role in the pathogenesis of constipation-related PD, mostly through the decreasing of SCFA-producing bacteria, indicating that probiotics with SCFA-producing bacteria may be promising in the prevention and treatment of constipation-related PD.

Limitations

1) Several potential confounders that should be adjusted were not provided in the original dataset. 2) Our study was conducted based on the assumption of constipation being the etiology of PD; however, constipation and PD may mutually affect each other. 3) Further studies are necessary to explain the remaining 23.44% effect leading to PD by constipation.

Parkinson's disease related mortality: Long-term trends and impact of COVID-19 pandemic waves

Introduction

Parkinson's disease (PD) mortality burden is increasing worldwide, but accurate estimates on the magnitude of the impact of the COVID-19 pandemic are missing. Mortality rates vary largely when considering PD as underlying cause of death (UCOD), or as one among multiple causes reported in death certificates (MCOD). The aim of this study is to assess COVID-19 impact on PD-related mortality trends using the UCOD and MCOD approach.

Methods

Mortality records between 01/2008-12/2020 of residents aged ≥45 years in Veneto Region (Northeastern Italy) with any mention of PD were collected. Age-standardized sex-specific mortality rates were estimated for PD-related deaths as UCOD and MCOD to assess time trends. The average annual percentage change in age-standardized rates (AAPC) was estimated by linear regression models. Monthly mortality in 2020, the first year of the pandemic, was plotted against the 2018–2019 average.

Results

Overall, 13,746 PD-related deaths (2.3% of all deaths) were identified, 52% males, median age 84 years. Proportional mortality increased from 1.9% (2008) to 2.8% (2020). AAPC through 2008–2019 was +5.2% for males and +5.3% for females in analyses of the UCOD, and +1.4% in both genders based on MCOD. Excess in PD-related mortality during 2020 corresponded to 19% for UCOD and 28% for MCOD, with the latter showing two peaks corresponding to the first (28%) and second (59%) pandemic waves.

Conclusion

Age-standardized PD-related mortality rates have steeply increased during COVID-19 pandemic, amplifying a pre-existing long-term trend. Hence, surveillance of mortality associated to PD is warranted in the forthcoming pandemic and post-pandemic years.

Neuropathological and Clinical Correlates of Lewy Body Disease Survival by Race and Ethnicity in the National Alzheimer's Coordinating Center

BACKGROUND

Survival and associated clinical and pathological characteristics in Lewy body disease (LBD)-related dementias are understudied. Available studies focus primarily on white non-Hispanic samples.

OBJECTIVE

We investigated demographic, clinical, and pathological correlates of survival by race and ethnicity in an autopsy-confirmed cohort of LBD cases.

METHODS

Using National Alzheimer's Coordinating Center data, we selected participants who self-identified as Black, Hispanic, or white who had neuropathological assessments showing transitional or diffuse LBD pathology. We used Kruskal-Wallis and Pearson χ2 analyses to investigate group differences in demographic and presenting clinical and pathological characteristics. We used linear regressions to identify predictors of survival with sex, age at symptom onset, education, ethnoracial status, LBD pathology type, and Braak tangle stage included in the model.

RESULTS

Data from 1,441 white, 60 Black, and 54 Hispanic participants were available for analysis. Hispanics were more likely to have transitional LBD pathology and had a longer survival than white and Black participants. After controlling for demographic and pathological variables, length of survival did not differ between Hispanics and Black or white participants. Additional key findings demonstrated discrepancies between clinical diagnoses received at last visit and pathological findings, particularly among Black participants.

CONCLUSION

LBD survival differences by race and ethnicity can be accounted for by LBD pathology type and co-occurring Alzheimer's disease pathology. The discrepancies between clinical diagnoses and pathological findings raise the concern that dementia with Lewy bodies is underdiagnosed in NACC, especially for Black older adults.