Sex Differences in Clinical Features of Early, Treated Parkinson's Disease

Cardiovascular dysautonomia and cognitive impairment in Parkinson's disease (Review)

Cognitive impairment is a prevalent non-motor symptom of Parkinson's disease (PD), which can result in significant disability and distress for patients and caregivers. There is a marked variation in the timing, characteristics and rate at which cognitive decline occurs in patients with PD. This decline can vary from normal cognition to mild cognitive impairment and dementia. Cognitive impairment is associated with several pathophysiological mechanisms, including the accumulation of β-amyloid and tau in the brain, oxidative stress and neuroinflammation. Cardiovascular autonomic dysfunctions are commonly observed in patients with PD. These dysfunctions play a role in the progression of cognitive impairment, the incidents of falls and even in mortality. The majority of symptoms of dysautonomia arise from changes in the peripheral autonomic nervous system, including both the sympathetic and parasympathetic nervous systems. Cardiovascular changes, including orthostatic hypotension, supine hypertension and abnormal nocturnal blood pressure (BP), can occur in both the early and advanced stages of PD. These changes tend to increase as the disease advances. The present review aimed to describe the cognitive changes in the setting of cardiovascular dysautonomia and to discuss strategies through which these changes can be modified and managed. It is a multifactorial process usually involving decreased blood flow to the brain, resulting in the development of cerebral ischemic lesions, an increased presence of abnormal white matter signals in the brain, and a potential influence on the process of neurodegeneration in PD. Another possible explanation is this association being independent observations of PD progression. Patients with clinical symptoms of dysautonomia should undergo 24-h ambulatory BP monitoring, as they are frequently subtle and underdiagnosed.

Sex-dependent associations of serum BDNF, glycolipid metabolism and cognitive impairments in Parkinson's disease with depression: a comprehensive analysis

Brain-derived neurotrophic factor (BDNF) and glycolipid metabolism have been implicated in cognitive impairments and depression among Parkinson's disease (PD). However, the role of sex differences in this relationship remains elusive. This study aimed to investigate the potential sex differences in the link between serum BDNF levels, glycolipid metabolism and cognitive performance among depressive PD patients. PD patients comprising 108 individuals with depression and 108 without depression were recruited for this study. Cognitive function was assessed using the Montreal Cognitive Assessment Beijing version (MOCA-BJ). The severity of depressive symptoms was assessed using the Hamilton Depression Rating Scale (HAMD-17), while motor symptoms were evaluated using the Revised Hoehn and Yahr rating scale (H-Y) and the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). Laboratory testing and enzyme-linked immunosorbent assay (ELISA) are used to measure serum levels of glycolipid metabolism and BDNF. Females showed superior performance in delayed recall (all p < 0.05), male PD patients exhibited higher scores in naming tasks compared to females in non-depression group. There was no sex differences in serum BDNF levels between depression and non-depression groups. Liner regression analysis indicated BDNF as an independent risk factor for language deficits in male PD patients with depression (p < 0.05), while cholesterol (CHOL) emerged as a cognitive influencing factor, particularly in delayed recall among male PD patients with depression (p < 0.05). Our study reveals extensive cognitive impairments in PD patients with depression. Moreover, BDNF and CHOL may contribute to the pathological mechanisms underlying cognitive deficits, particularly in male patients with depression.

Unraveling sex differences in Parkinson's disease through explainable machine learning

Sex differences affect Parkinson's disease (PD) development and manifestation. Yet, current PD identification and treatments underuse these distinctions. Sex-focused PD literature often prioritizes prevalence rates over feature importance analysis. However, underlying aspects could make a feature significant for predicting PD, despite its score. Interactions between features require consideration, as do distinctions between scoring disparities and actual feature importance. For instance, a higher score in males for a certain feature doesn't necessarily mean it's less important for characterizing PD in females. This article proposes an explainable Machine Learning (ML) model to elucidate these underlying factors, emphasizing the importance of features. This insight could be critical for personalized medicine, suggesting the need to tailor data collection and analysis for males and females. The model identifies sex-specific differences in PD, aiding in predicting outcomes as "Healthy" or "Pathological". It adopts a system-level approach, integrating heterogeneous data - clinical, imaging, genetics, and demographics - to study new biomarkers for diagnosis. The explainable ML approach aids non-ML experts in understanding model decisions, fostering trust and facilitating interpretation of complex ML outcomes, thus enhancing usability and translational research. The ML model identifies muscle rigidity, autonomic and cognitive assessments, and family history as key contributors to PD diagnosis, with sex differences noted. The genetic variant SNCA-rs356181 may be more significant in characterizing PD in males. Interaction analysis reveals a greater occurrence of feature interplay among males compared to females. These disparities offer insights into PD pathophysiology and could guide the development of sex-specific diagnostic and therapeutic approaches.

The role of autophagy in Parkinson's disease: a gender difference overview

Recent studies have demonstrated dysregulation of the autophagy pathway in patients with Parkinson's disease (PD) and in animal models of PD, highlighting its emerging role in disease. In particular, several studies indicate that autophagy, which is an essential degradative process for the damaged protein homeostasis and the management of cell balance, can manifest significant variations according to gender. While some evidence suggests increased autophagic activation in men with PD, women may have distinct regulatory patterns. In this review, we examined the existing literature on gender differences in PD-associated autophagic processes, focusing on the autophagy related proteins (ATGs) and leucine rich repeat kinase 2 (LRRK2) genes. Also, this review would suggest that an in-depth understanding of these gender differences in autophagic processes could open new perspectives for personalized therapeutic strategies, promoting more effective and targeted management of PD.

Quality of life assessment when considering the introduction of device-assisted therapies in advanced Parkinson's disease: A retrospective observational cross-sectional study

INTRODUCTION

Device-aided therapy (DAT) is an established treatment for improving the quality of life (QOL) in individuals with advanced Parkinson's disease (APD). Criteria for starting DAT, including motor and non-motor symptoms, have been proposed. However, it remains unclear whether QOL differences among patients with APD influence DAT introduction. Therefore, we aimed to investigate QOL differences between patients with and without DAT introduction.

METHODS

This retrospective observational cross-sectional study included 245 patients with PD who were followed up between January 1, 2020, and June 30, 2022. We defined cases that underwent DAT introduction after evaluation as "planned-DAT" and those that did not as "not-planned-DAT." We performed between-group comparisons of the PD questionnaire-39 (PDQ-39) summary index (SI) in patients with APD who met the 5-2-1 criteria (≥5 times the oral levodopa dose/day, ≥2 h of "off" symptoms/day, and ≥ 1 h of troublesome dyskinesia/day).

RESULTS

Seventy-nine patients met the inclusion criteria for APD (median age: 68 [61.0-73.0] years; 62.8% [N = 52] women). The PDQ-39 SI scores were higher in the planned-DAT group (N = 12) than in the not-planned-DAT group (N = 67) (29.2 [22.1-33.6] vs. 19.0 [10.3-49.6] points, P < 0.05). After propensity-score matching according to age and sex, the PDQ-39 SI scores remained higher in the planned-DAT (N = 9) than in the not-planned-DAT group (N = 18) (40.0 [25.4-60.0] vs. 18.5 [7.9-46.8] points, P < 0.05).

CONCLUSIONS

Our results suggest that QOL assessment using PDQ-39 can be used to identify patients eligible for DAT.

Association of women-specific health factors in the severity of Parkinson's disease

Parkinson's disease (PD) is an age-related neurological disorder known for the observational differences in its risk, progression, and severity between men and women. While estrogen has been considered to be a protective factor in the development of PD, there is little known about the role that fluctuations in hormones and immune responses from sex-specific health experiences have in the disease's development and severity. We sought to identify women-specific health experiences associated with PD severity, after adjusting for known PD factors, by developing and distributing a women-specific questionnaire across the United States and creating multivariable models for PD severity. We created a questionnaire that addresses women's specific experiences and their PD clinical history and deployed it through The Parkinson's Foundation: PD Generation. To determine the association between women-specific health factors and PD severity, we constructed multivariable logistic regression models based on the MDS-UPDRS scale and the participants' questionnaire responses, genetics, and clinical data. For our initial launch in November 2021, we had 304 complete responses from PD GENEration. Univariate and multivariate logistic modeling found significant associations between major depressive disorder, perinatal depression, natural childbirth, LRRK2 genotype, B12 deficiency, total hysterectomy, and increased PD severity. This study is a nationally available questionnaire for women's health and PD. It shifts the paradigm in understanding PD etiology and acknowledging how sex-specific experiences may contribute to PD severity. In addition, the work in this study sets the foundation for future research to investigate the factors behind sex differences in PD.

Sex Differences in Motor and Non-Motor Symptoms among Spanish Patients with Parkinson's Disease

BACKGROUND AND OBJECTIVE

Sex plays a role in Parkinson's disease (PD) mechanisms. We analyzed sex difference manifestations among Spanish patients with PD.

PATIENTS AND METHODS

PD patients who were recruited from the Spanish cohort COPPADIS from January 2016 to November 2017 were included. A cross-sectional and a two-year follow-up analysis were conducted. Univariate analyses and general linear model repeated measure were used.

RESULTS

At baseline, data from 681 PD patients (mean age 62.54 ± 8.93) fit the criteria for analysis. Of them, 410 (60.2%) were males and 271 (39.8%) females. There were no differences between the groups in mean age (62.36 ± 8.73 vs. 62.8 ± 9.24; p = 0.297) or in the time from symptoms onset (5.66 ± 4.65 vs. 5.21 ± 4.11; p = 0.259). Symptoms such as depression (p < 0.0001), fatigue (p < 0.0001), and pain (p < 0.00001) were more frequent and/or severe in females, whereas other symptoms such as hypomimia (p < 0.0001), speech problems (p < 0.0001), rigidity (p < 0.0001), and hypersexuality (p < 0.0001) were more noted in males. Women received a lower levodopa equivalent daily dose (p = 0.002). Perception of quality of life was generally worse in females (PDQ-39, p = 0.002; EUROHIS-QOL8, p = 0.009). After the two-year follow-up, the NMS burden (Non-Motor Symptoms Scale total score) increased more significantly in males (p = 0.012) but the functional capacity (Schwab and England Activities of Daily Living Scale) was more impaired in females (p = 0.001).

CONCLUSION

The present study demonstrates that there are important sex differences in PD. Long-term prospective comparative studies are needed.

Sex and Gender Differences in Parkinson's Disease

The lower prevalence of Parkinson disease (PD) in females is not well understood but may be partially explained by sex differences in nigrostriatal circuitry and possible neuroprotective effects of estrogen. PD motor and nonmotor symptoms differ between sexes, and women experience disparities in care including undertreatment with DBS and less access to caregiving. Our knowledge about PD in gender diverse individuals is limited. Future studies should improve our understanding of the role of hormone replacement therapy in PD, address gender-based inequities in PD care and expand our understanding of PD in SGM and marginalized communities.

Gender differences in motor and non-motor symptoms in individuals with mild-moderate Parkinson's disease

BACKGROUND

Parkinson's disease (PD) affects both men and women with documented gender differences across functional domains, with findings varying among reports. Knowledge regarding gender differences in PD for different geographic locations is important for further understanding of the disease and for developing personalized gender-specific PD assessment tools and therapies.

OBJECTIVE

This study aimed to examine gender differences in PD-related motor, motor-cognitive, cognitive, and psychosocial function in people with PD from the southern United States (US).

METHODS

199 (127 men and 72 women; M age: 69.08±8.94) individuals with mild-moderate idiopathic PD (Hoehn &Yahr (H&Y) Median = 2, stages I-III) from a large metro area in the southeastern US were included in this retrospective, cross-sectional study. Motor, motor-cognitive, cognitive, and psychosocial data were obtained using standardized and validated clinical tests. Univariate analyses were performed, adjusting for age and housing type.

RESULTS

After adjustment for age, housing, PD duration and fall rate, men exhibited statistically significantly greater motor (Movement Disorders Society (MDS)-Unified Parkinson Disease Rating Scale (UPDRS)-II) and non-motor (MDS-UPDRS-I) impact of PD, and more severe motor signs (MDS-UPDRS-III). Men exhibited worse PD-specific health-related quality of life related to mobility, activities of daily living, emotional well-being, cognitive impairment, communication, and more depressive symptoms. Men performed worse on a subtraction working memory task. Women had slower fast gait speed.

CONCLUSIONS

In the southeastern United States, men may experience worse PD-related quality of life and more depression than women. Many non-motor and motor variables that are not PD specific show no differences between genders in this cohort. These findings can contribute to the development of gender-sensitive assessment and rehabilitation policies and protocols for people with PD.

The quality of life in patients with Parkinson's disease: Focus on gender difference

BACKGROUND

To improve understanding of gender differences on quality of life (QoL) in patients with Parkinson's disease (PWP) of a different race, the differences of clinical features and health-related quality of life (HRQoL) between male and female PWP were studied in a small cohort early to middle stage of Chinese PWP.

METHODS

A cross-sectional study was carried out. PWP were consecutively included from April 2020 to July 2021 in Beijing Rehabilitation Hospital. HRQoL, motor symptoms, and nonmotor symptoms in each patient were evaluated. The differences of demographic, motor symptoms assessments, nonmotor symptoms assessments, and QoL between two gender groups were tested using t-test statistics, Mann-Whitney-Wilcoxon test, or χ² depending on the data type. To eliminate the possible factors contributing to the QoL, linear regression models were constructed to sort out the effect of gender.

RESULTS

One hundred and sixty-two Parkinson's disease (PD) patients were included. Demographic, clinical characteristics, and symptom scale assessments had no statistical differences except for levodopa equivalent daily dose, Hamilton Anxiety Rating Score, REM sleep behavior disorder sleep questionnaire, and Hyposmia Rating Scale score. After baseline imbalance corrections, a significantly higher score of PD Questionnaire-39 (PDQ-39) in female than in male patients(p<.05) was found. In the questionnaire, summary Index and bodily discomfort, stigma, and emotional well-being subscores were the main contribution differences.

CONCLUSIONS

Gender differences are associated with the QoL in the early to middle stage PWP in China. Female patients have poorer QoL than male patients, especially bodily discomfort, stigma, and emotional well-being.

Contributions of sex, depression, and cognition on brain connectivity dynamics in Parkinson's disease

Alterations in time-varying functional connectivity (FC) have been found in Parkinson's disease (PD) patients. To date, very little is known about the influence of sex on brain FC in PD patients and how this could be related to disease severity. The first objective was to evaluate the influence of sex on dynamic FC characteristics in PD patients and healthy controls (HC), while the second aim was to investigate the temporal patterns of dynamic connectivity related to PD motor and non-motor symptoms. Ninety-nine PD patients and sixty-two HC underwent a neuropsychological and clinical assessment. Rs-fMRI and T1-weighted MRI were also acquired. Dynamic FC analyses were performed in the GIFT toolbox. Dynamic FC analyses identified two States: State I, characterized by within-network positive coupling; and State II that showed between-network connectivity, mostly involving somatomotor and visual networks. Sex differences were found in dynamic indexes in HC but these differences were not observed in PD. Hierarchical clustering analysis identified three phenotypically distinct PD subgroups: (1) Subgroup A was characterized by mild motor symptoms; (2) Subgroup B was characterized by depressive and motor symptoms; (3) Subgroup C was characterized by cognitive and motor symptoms. Results revealed that changes in the temporal properties of connectivity were related to the motor/non-motor outcomes of PD severity. Findings suggest that while in HC sex differences may play a certain role in dynamic connectivity patterns, in PD patients, these effects may be overcome by the neurodegenerative process. Changes in the temporal properties of connectivity in PD were mainly related to the clinical markers of PD severity.

Cognitive Influences in Parkinson's Disease Patients and Their Caregivers: Perspectives From an Australian Cohort

Objectives: Cognitive impairment impacts negatively on Parkinson's disease (PD) patient and caregiver quality of life (QoL). We examined cognitive impairment in PD patients and their caregivers to determine if caregiver cognition affected their PD relative. Methods: Validated cognition and clinical outcome measures were assessed in 103 PD patients and 81 caregivers. Results: PD patients showed more cognitive impairment than their carers, with 48.6% having possible Mild Cognitive Impairment (MCI) and 16.5% having PD dementia. Increasing age, male gender, lower education level, various non-motor symptoms and certain therapies, associated with poorer cognition in PD. Eighteen and a half percent of caregivers were found to have MCI, in association with a lower physical and mental QoL. This reflected in lower QoL and mood for the respective PD patients. Conclusion: Impaired cognition and QoL in caregivers was associated with decreased QoL and mood for respective PD patients, suggesting MCI in caregivers is an important consideration for the management of PD.

The Impact of Sex on the Neurocognitive Functions of Patients with Parkinson's Disease

This study aimed to understand the impact of sex on the neurocognitive function of patients with Parkinson's disease (PD). Ninety-four participants with idiopathic PD and 167 age-matched healthy individuals as normal controls (NCs) were recruited and underwent comprehensive neuropsychological assessments. Sex differences were found in NCs, but not in patients with PD. Among male participants, patients with PD showed worse performance on the Digit Symbol Substitution (DSS) (p < 0.001) test and Symbol Search (SS) (p < 0.001) than NCs. Among female participants, patients with PD showed worse performance on the category score of the Modified Wisconsin Card Sorting Test (p < 0.001), SS (p < 0.001), and pentagon copying (p < 0.001) than NCs. After controlling for the effects of age and years of education, Hoehn and Yahr stage was found to predict the performance of the Color Trails Test part A (βA = 0.241, pA = 0.036), Stroop Color and Word Test (β = -0.245, p = 0.036), and DSS (β = -0.258, p = 0.035) in men with PD. These results indicate the differential effect of sex on the neurocognitive function among healthy aging and PD populations. The disappearance of sex differences, which is present in healthy aging, in patients with PD suggests a gradual loss of the neuroprotective effect of estrogen after the initiation of the neurodegenerative process. This study also found mental flexibility and visuospatial function to be the susceptible cognitive domains in women with PD, while the disease severity could predict the working memory and processing speed in men with PD.

The Trajectory of Motor Deterioration to Death in Parkinson's Disease

Background: Motor progression varies even among those with a single diagnosis such as Parkinson's disease (PD) and little is known about the trajectory of motor signs prior to death. Understanding deterioration patterns may help clinicians counsel patients and proactively plan interdisciplinary care, including palliative care. The objective of this study was to examine and describe Unified Parkinson's Disease Rating Scale motor score (UPDRS-III) trajectories at the end of life in PD. Methods: A retrospective chart review was performed for deceased PD patients who attended the Parkinson and Movement Disorders Program at the University of Alberta for at least 5 years between 1999 and 2018. UPDRS-III scores were recorded for all visits. Trajectory patterns were visualized with Loess curves stratified by sex and age at diagnosis. Piecewise linear models were used to individually model the UPDRS-III scores, and the trajectories obtained were clustered based on their features. Results: Among the 202 charts reviewed, 84 meeting inclusion criteria were analyzed. The UPDRS-III increased over time regardless of sex and age. Distinct trajectory variations present in PD (e.g., Consistent Deterioration, Stability-Deterioration, Improvement-Deterioration, Deterioration-Improvement-Deterioration) were identified. Twenty-five percent of the patients were classified as Undetermined/Irregular trajectories. In addition, regardless of trajectory type, many patients experienced a steep increase in UPDRS-III approaching death. Those with disease diagnosis after age 65 years had a shorter survival time, compared to PD patients with a younger age of onset. Conclusion: Our study identified dominant types of motor trajectory in PD that can help clinicians understand their patients' course of illness. This information can help counsel patients regarding the variability in motor deterioration and should alert physicians to recognize a terminal decline. Age of disease onset was correlated with survival time.

TOMM40 '523' poly-T repeat length is a determinant of longitudinal cognitive decline in Parkinson's disease

The translocase of outer mitochondrial membrane 40 (TOMM40) ‘523’ polymorphism has previously been associated with age of Alzheimer’s disease onset and cognitive functioning in non-pathological ageing, but has not been explored as a candidate risk marker for cognitive decline in Parkinson’s disease (PD). Therefore, this longitudinal study investigated the role of the ‘523’ variant in cognitive decline in a patient cohort from the Parkinson’s Progression Markers Initiative. As such, a group of 368 people with PD were assessed annually for cognitive performance using multiple neuropsychological protocols, and were genotyped for the TOMM40 ‘523’ variant using whole-genome sequencing data. Covariate-adjusted generalised linear mixed models were utilised to examine the relationship between TOMM40 ‘523’ allele lengths and cognitive scores, while taking into account the APOE ε genotype. Cognitive scores declined over the 5-year study period and were lower in males than in females. When accounting for APOE ε4, the TOMM40 ‘523’ variant was not robustly associated with overall cognitive performance. However, in APOE ε3/ε3 carriers, who accounted for ~60% of the whole cohort, carriage of shorter ‘523’ alleles was associated with more severe cognitive decline in both sexes, while carriage of the longer alleles in females were associated with better preservation of global cognition and a number of cognitive sub-domains, and with a delay in progression to dementia. The findings indicate that when taken in conjunction with the APOE genotype, TOMM40 ‘523’ allele length is a significant independent determinant and marker for the trajectory of cognitive decline and risk of dementia in PD.

Elevated HDL Levels Linked to Poorer Cognitive Ability in Females With Parkinson's Disease

Introduction

Cholesterol levels have been associated with age-related cognitive decline, however, such an association has not been comprehensively explored in people with Parkinson's disease (PD). To address this uncertainty, the current cross-sectional study examined the cholesterol profile and cognitive performance in a cohort of PD patients.

Methods

Cognitive function was evaluated using two validated assessments (ACE-R and SCOPA-COG) in 182 people with PD from the Australian Parkinson's Disease Registry. Total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and Triglyceride (TRG) levels were examined within this cohort. The influence of individual lipid subfractions on domain-specific cognitive performance was investigated using covariate-adjusted generalised linear models.

Results

Females with PD exhibited significantly higher lipid subfraction levels (TC, HDL, and LDL) when compared to male counterparts. While accounting for covariates, HDL levels were strongly associated with poorer performance across multiple cognitive domains in females but not males. Conversely, TC and LDL levels were not associated with cognitive status in people with PD.

Conclusion

Higher serum HDL associates with poorer cognitive function in females with PD and presents a sex-specific biomarker for cognitive impairment in PD.

Sex as an important factor in nanomedicine

Nanomedicine has demonstrated substantial potential to improve the quality and efficacy of healthcare systems. Although the promise of nanomedicine to transform conventional medicine is evident, significant numbers of therapeutic nanomedicine products have failed in clinical trials. Most studies in nanomedicine have overlooked several important factors, including the significance of sex differences at various physiological levels. This report attempts to highlight the importance of sex in nanomedicine at cellular and molecular level. A more thorough consideration of sex physiology, among other critical variations (e.g., health status of individuals), would enable researchers to design and develop safer and more-efficient sex-specific diagnostic and therapeutic nanomedicine products.

Cognitive Impairment in Parkinson's Disease: Epidemiology, Clinical Profile, Protective and Risk Factors

Cognitive impairment is a common non-motor symptom in Parkinson's Disease (PD) and an important source of patient disability and caregiver burden. The timing, profile and rate of cognitive decline varies widely among individuals with PD and can range from normal cognition to mild cognitive impairment (PD-MCI) and dementia (PDD). Beta-amyloid and tau brain accumulation, oxidative stress and neuroinflammation are reported risk factors for cognitive impairment. Traumatic brain injury and pesticide and tobacco exposure have also been described. Genetic risk factors including genes such as COMT, APOE, MAPT and BDNF may also play a role. Less is known about protective factors, although the Mediterranean diet and exercise may fall in this category. Nonetheless, there is conflicting evidence for most of the factors that have been studied. The use of inconsistent criteria and lack of comprehensive assessment in many studies are important methodological issues. Timing of exposure also plays a crucial role, although identification of the correct time window has been historically difficult in PD. Our understanding of the mechanism behind these factors, as well as the interactions between gene and environment as determinants of disease phenotype and the identification of modifiable risk factors will be paramount, as this will allow for potential interventions even in established PD.

Is there a Neurobiological Rationale for the Utility of the Iowa Gambling Task in Parkinson's Disease?

Up to 23% of newly diagnosed, non-demented, Parkinson’s disease (PD) patients experience deficits in executive functioning (EF). In fact, EF deficits may occur up to 39-months prior to the onset of motor decline. Optimal EF requires working memory, attention, cognitive flexibility, and response inhibition underlying appropriate decision-making. The capacity for making strategic decisions requires inhibiting imprudent decisions and are associated with noradrenergic and dopaminergic signaling in prefrontal and orbitofrontal cortex. Catecholaminergic dysfunction and the loss of noradrenergic and dopaminergic cell bodies early in PD progression in the aforementioned cortical areas likely contribute to EF deficits resulting in non-strategic decision-making. Thus, detecting these deficits early in the disease process could help identify a significant portion of individuals with PD pathology (14–60%) before frank motor impairment. A task to evaluate EF in the domain of non-strategic decision-making might be useful to indicate the moderate loss of catecholamines that occurs early in PD pathology prior to motor decline and cognitive impairment. In this review, we focus on the potential utility of the Iowa Gambling Task (IGT) for this purpose, given significant overlap between in loss of dopaminergic and noradrenergic cells bodies in early PD and the deficits in catecholamine function associated with decreased EF. As such, given the loss of catecholamines already well-underway after PD diagnosis, we evaluate the potential utility of the IGT to identify the risk of therapeutic non-compliance and a potential companion approach to detect PD in premotor stages.

Differential effects of sex on longitudinal patterns of cognitive decline in Parkinson's disease

Background

Cognitive impairment is an important and diverse symptom of Parkinson’s disease (PD). Sex is a purported risk variable for cognitive decline in PD, but has not been comprehensively investigated.

Objectives

This cross-sectional and longitudinal study examined sex differences in global and domain-specific cognitive performance in a large PD cohort.

Methods

Cognitive function was evaluated using the Addenbrooke’s Cognitive Examination in 392 people with PD (PwP) from the Australian Parkinson’s Disease Registry. The influence of sex on domain-specific cognitive performance was investigated using covariate-corrected generalised linear models. In a repeated measures longitudinal subset of 127 PwP, linear mixed models were used to assess the impact of sex on cognition over time, while accounting for covariates.

Results

Cross-sectional-corrected modelling revealed that sex was significantly predictive of cognitive performance, with males performing worse than females on global cognition, and memory and fluency domains. Longitudinally, sex was significantly predictive of cognitive decline, with males exhibiting a greater reduction in global cognition and language, whereas females showed a greater decline in attention/orientation, memory and visuospatial domains, despite starting with higher baseline scores. At follow-up, a significantly higher proportion of males than females fulfilled criteria for mild cognitive impairment or PD dementia.

Conclusions

Sex was revealed as a significant determinant of overall cognitive performance as well as specific cognitive domains, with a differential pattern of decline in male and female participants. Such sex-specific findings appear to explain some of the heterogeneity observed in PD, warranting further investigation of mechanisms underlying this sexual dimorphism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-020-10367-8.

Sex Differences in Response to Triptans: A Systematic Review and Meta-analysis

OBJECTIVE

To examine the effect of sex on clinical response to triptans in migraine and to determine whether these differences are related to pharmacokinetics of triptans in men and women, we performed a systematic review and meta-analysis.

METHODS

We searched clinical trials distinguishing clinical response to or pharmacokinetic parameters of triptans between sexes in PubMed, MEDLINE, Cochrane Library, Embase, and Web of Science up to Dec 12, 2019. Analysis was based on data extracted from published reports. Male-to-female pooled risk ratios (RR) were calculated for clinical outcomes and pooled ratio of means (RoM) for pharmacokinetic outcomes using random-effects models.

RESULTS

Of 1,188 publications on clinical trials with triptans, 244 were identified with sex-related search terms. Only 19 publications presented sex-specific results, comprising n = 2,280 men and n = 13,899 women. No sex differences were revealed for 2-hour headache and pain-free responses, but men had a lower risk for headache recurrence (male-to-female RR 0.64, 95% confidence interval [CI]: 0.55-0.76, Q = 0.81) and adverse events (RR 0.82, 95% CI: 0.72-0.93, Q = 4.93). Men had lower drug exposure with lower area under the curve (RoM 0.69, 95% CI: 0.60-0.81, Q = 18.06) and peak drug concentration (RoM 0.72, 95% CI: 0.64-0.82, Q = 8.24) than women.

CONCLUSIONS

Remarkably few publications about sex differences in triptan response are available. The limited number of eligible studies show sex differences in adverse event frequency, which may be partly because of drug exposure differences. This higher drug exposure in women is not reflected in different response rates. Despite higher exposure, women have higher headache recurrence rates possibly because of longer attack duration related to sex hormonal changes.

Can sex influence the neurocognition of language? Evidence from Parkinson's disease

Parkinson's disease (PD), which involves basal ganglia degeneration, affects language as well as motor function. However, which aspects of language are impaired in PD and under what circumstances remains unclear. We examined whether lexical and grammatical aspects of language are differentially affected in PD, and whether this dissociation is moderated by sex as well as the degree of basal ganglia degeneration. Our predictions were based on the declarative/procedural model of language. The model posits that grammatical composition, including in regular inflection, depends importantly on left basal ganglia procedural memory circuits, whereas irregular and other lexicalized forms are memorized in declarative memory. Since females tend to show declarative memory advantages as compared to males, the model further posits that females should tend to rely on this system for regulars, which can be stored as lexicalized chunks. We tested non-demented male and female PD patients and healthy control participants on the intensively studied paradigm of English regular and irregular past-tense production. Mixed-effects regression revealed PD deficits only at regular inflection, only in male patients. The degree of left basal ganglia degeneration, as reflected by right-side hypokinesia, predicted only regular inflection, and only in male patients. Left-side hypokinesia did not show this pattern. Past-tense frequency effects suggested that the female patients retrieved regular as well as irregular past-tense forms from declarative memory, whereas the males retrieved only irregulars. Sensitivity analyses showed that the pattern of findings was robust. The results, which are consistent with the declarative/procedural model, suggest a grammatical deficit in PD due to left basal ganglia degeneration, with a relative sparing of lexical retrieval. Female patients appear to compensate for this deficit by relying on chunks stored in declarative memory. More generally, the study elucidates the neurocognition of inflectional morphology and provides evidence that sex can influence how language is computed in the mind and brain.

Effect of Caffeine Consumption on the Risk for Neurological and Psychiatric Disorders: Sex Differences in Human

Caffeine occurs naturally in various foods, such as coffee, tea, and cocoa, and it has been used safely as a mild stimulant for a long time. However, excessive caffeine consumption (1~1.5 g/day) can cause caffeine poisoning (caffeinism), which includes symptoms such as anxiety, agitation, insomnia, and gastrointestinal disorders. Recently, there has been increasing interest in the effect of caffeine consumption as a protective factor or risk factor for neurological and psychiatric disorders. Currently, the importance of personalized medicine is being emphasized, and research on sex/gender differences needs to be conducted. Our review focuses on the effect of caffeine consumption on several neurological and psychiatric disorders with respect to sex differences to provide a better understanding of caffeine use as a risk or protective factor for those disorders. The findings may help establish new strategies for developing sex-specific caffeine therapies.

Early-onset Parkinsonian behaviors in female Pink1-/- rats

Parkinson disease (PD) is a progressive, neurological disease that affects millions of individuals worldwide. Although instability, rigidity, tremor, and bradykinesia are considered hallmark motor signs of the disease, these are not apparent until mid-to-late stage. In addition to limb motor impairment, individuals with PD also exhibit early-onset speech dysfunction and reduced vocal intelligibility as well as anhedonia and anxiety. Many of these clinical signs vary according to sex in humans with PD. In this study, a translational genetic rat model of early-onset PD (Pink1-/-) was used to address significant gaps in knowledge concerning sex-specific characteristics of limb sensorimotor deficits, vocal motor dysfunction, and changes in affective state. Traditional behavioral tests of limb function, ultrasonic vocalization, anxiety, and anhedonia in the Pink1-/- female rat and wildtype controls were used to test the hypothesis that behavioral performance would significantly differ between genotypes, and that these differences would increase with disease progression (age of the rat). Results demonstrate that Pink1-/- female rats do not exhibit limb sensorimotor deficits but do have significantly reduced intensity (loudness) of vocalizations, and present with anhedonia and anxiety by 8 months of age. Consistent with an early-disease model, Pink1-/- female rats do not exhibit significant decreases in nigrostriatal catecholamines/metabolites, as measured by HPLC. These results are significant in expanding knowledge of early-onset deficits in the female Pink1-/- genetic rat model of PD.

Sex differences in movement disorders

In a range of neurological conditions, including movement disorders, sex-related differences are emerging not only in brain anatomy and function, but also in pathogenesis, clinical features and response to treatment. In Parkinson disease (PD), for example, oestrogens can influence the severity of motor symptoms, whereas elevation of androgens can exacerbate tic disorders. Nevertheless, the real impact of sex differences in movement disorders remains under-recognized. In this article, we provide an up-to-date review of sex-related differences in PD and the most common hyperkinetic movement disorders, namely, essential tremor, dystonia, Huntington disease and other chorea syndromes, and Tourette syndrome and other chronic tic disorders. We highlight the most relevant clinical aspects of movement disorders that differ between men and women. Increased recognition of these differences and their impact on patient care could aid the development of tailored approaches to the management of movement disorders and enable the optimization of preclinical research and clinical studies.

[Remote assessment of idiopathic Parkinson's disease : Developments in diagnostics, monitoring and treatment]

The idiopathic Parkinson's disease (iPD) is a progressive neurodegenerative disorder primarily resulting in impaired movement execution. In the course of the disease symptom fluctuation is common and makes adequate treatment difficult. In this overview the current approaches using modern and especially mobile technologies for diagnosis, monitoring and treatment of iPD are presented. Currently, there are no medical aids ready for point of care application; however, the development of these technologies has great potential for improving care for patients suffering from iPD.

What Effects Might Exenatide have on Non-Motor Symptoms in Parkinson's Disease: A Post Hoc Analysis

BACKGROUND

Exenatide is a GLP-1 receptor agonist that was recently studied for potential disease-modifying effects in a randomised, placebo-controlled clinical trial in patients with moderate stage Parkinson's disease, and showed positive effects on the motor severity of the disease which were sustained 12 weeks beyond the period of exenatide exposure. Analysis of pre-defined secondary outcomes revealed no statistically significant differences between patients treated with exenatide in total non-motor symptom burden and overall quality of life measures.

OBJECTIVE

The response of individual non-motor symptoms to an intervention may vary and thus this post hoc analysis was conducted to explore the possible effects of exenatide compared to placebo on individual non-motor symptoms.

RESULTS

Compared to placebo, patients treated with exenatide-once weekly had greater improvements in individual domains assessing mood/depression across all observer-rated outcome measures after 48 weeks including the "mood/apathy" domain of the NMSS, - 3.3 points (95% CI - 6.2, - 0.4), p = 0.026; the "mood" score (Q1.3+Q1.4 of the MDS-UPDRS Part 1), - 0.3 points (95% CI - 0.6, - 0.1), p = 0.034; and a trend in the MADRS total score, - 1.7 points (95% CI - 3.6, 0.2), p = 0.071. In addition, there was an improvement in the "emotional well-being" domain of the PDQ-39 of 5.7 points ((95% CI - 11.3, - 0.1), p = 0.047 though these improvements were not sustained 12 weeks after exenatide withdrawal. At 48 weeks these changes were of a magnitude that would be subjectively meaningful to patients and were not associated with changes in motor severity or other factors, suggesting exenatide may exert independent effects on mood dysfunction.

CONCLUSIONS

These exploratory findings will contribute to the design of future trials to confirm the extent of motor and non-motor symptom effects of exenatide in larger cohorts of patients.

Do Microglial Sex Differences Contribute to Sex Differences in Neurodegenerative Diseases?

Sex differences have been clinically documented in numerous neurodegenerative diseases and yet the reasons for these differences are not well understood. Recent studies have found that microglia, the innate immune cells of the central nervous system, are a key cell type involved in neurodegenerative diseases. This cell type displays sex differences in their expression profiles and function. Could these sex differences in microglia explain the sex differences seen in neurodegenerative diseases? How can we further probe these differences to better understand disease mechanisms? In this Opinion, we highlight the recent evidence that microglia have sex differences, factors that contribute to these differences, and how these differences could shed new light on the pathophysiology of neurological diseases.

Cortico-basal white matter alterations occurring in Parkinson's disease

Magnetic resonance imaging studies typically use standard anatomical atlases for identification and analyses of (patho-)physiological effects on specific brain areas; these atlases often fail to incorporate neuroanatomical alterations that may occur with both age and disease. The present study utilizes Parkinson's disease and age-specific anatomical atlases of the subthalamic nucleus for diffusion tractography, assessing tracts that run between the subthalamic nucleus and a-priori defined cortical areas known to be affected by Parkinson's disease. The results show that the strength of white matter fiber tracts appear to remain structurally unaffected by disease. Contrary to that, Fractional Anisotropy values were shown to decrease in Parkinson's disease patients for connections between the subthalamic nucleus and the pars opercularis of the inferior frontal gyrus, anterior cingulate cortex, the dorsolateral prefrontal cortex and the pre-supplementary motor, collectively involved in preparatory motor control, decision making and task monitoring. While the biological underpinnings of fractional anisotropy alterations remain elusive, they may nonetheless be used as an index of Parkinson's disease. Moreover, we find that failing to account for structural changes occurring in the subthalamic nucleus with age and disease reduce the accuracy and influence the results of tractography, highlighting the importance of using appropriate atlases for tractography.

Dementia-Related Functional Disability in Moderate to Advanced Parkinson's Disease: Assessment Using the World Health Organization Disability Assessment Schedule 2.0

Dementia is a common nonmotor condition among people with moderate or advanced Parkinson’s disease (PD). Undoubtedly, profound motor symptoms cause remarkable impairment in daily activities; however, dementia-related disabilities have not been thoroughly investigated, especially not with consideration of differences according to sex. The present study used the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) to compare the functional disability between men and women with PD (PwP) with and without dementia. This study employed a registry of disability evaluation and functional assessment using the Taiwan Data Bank of Persons with Disability between July 2012 and October 2018. To investigate dementia-related disability in PwP, 1:1 matching by age and Hoehn-Yahr stage was conducted, which resulted in the inclusion of 1605 study participants in each group. The present study demonstrated that among the six major domains of WHODAS 2.0, the section of “Getting alone with others” was significantly worse in both genders of PwP with dementia; however, a greater disability in fulfilling activities of daily living was only noted in male PwP with dementia but not in their female counterparts. Neither the inability to provide self-care nor participation were significantly different between the sexes. Our findings suggested that deteriorating social relationships were a dementia-related disability in all PwP at the moderate and advanced disease stages. Regarding the performance of activities of daily living, deterioration was related to dementia only in male PwP. Such disabilities could indicate cognitive impairment in people with moderate or advanced PD and could be used as an indicator for the early detection of dementia in PwP by healthcare professionals through the easier functional assessment of the WHODAS 2.0.

Sex Differences in Cardiovascular Risk Factors for Dementia

Dementia, characterized by a progressive cognitive decline and a cumulative inability to behave independently, is highly associated with other diseases. Various cardiovascular disorders, such as coronary artery disease and atrial fibrillation, are well-known risk factors for dementia. Currently, increasing evidence suggests that sex factors may play an important role in the pathogenesis of diseases, including cardiovascular disease and dementia. Recent studies show that nearly two-thirds of patients diagnosed with Alzheimer’s disease are women; however, the incidence difference between men and women remains vague. Therefore, studies are needed to investigate sex-specific differences, which can help understand the pathophysiology of dementia and identify potential therapeutic targets for both sexes. In the present review, we summarize sex differences in the prevalence and incidence of dementia by subtypes. This review also describes sex differences in the risk factors of dementia and examines the impact of risk factors on the incidence of dementia in both sexes.

Cortisol levels, motor, cognitive and behavioral symptoms in Parkinson's disease: a systematic review

Parkinson's disease (PD) is a progressive and multifactorial neurodegenerative disease. It has been suggested that a dysregulation of the hypothalamic-pituitary-adrenal axis (HPA) occurs in PD. Furthermore, this dysregulation may be involved in triggering, exacerbation or progression of disease. The objective of this study was to systematically review the literature regarding cortisol levels and their relation with motor, cognitive and behavioral symptoms in patients with PD. A systematic search was performed in PubMed and Embase databases, according to PRISMA norms. Twenty-one studies were included, which evaluated baseline levels of cortisol and motor, cognitive, behavioral symptoms, drugs administration or deep brain stimulation to PD treatment. Sample size ranged from 7 to 249 individuals. In 14 studies that assessed cortisol levels in PD patients, seven showed elevation of cortisol levels. In relation to symptomatology, high levels of cortisol were associated with worst functional scores evaluated by UPDRS, depression and behavior in risk preference. Medication interactions showed an influence on the regulation of cortisol release, mainly, conventional drugs used in the PD's treatment, such as levodopa. The results found in this review point to a possible relationship between cortisol levels and symptoms in PD, indicating that an HPA axis dysfunction related to cortisol level occurs in PD.

Cognitive Profiles and Hub Vulnerability in Parkinson's Disease

The clinicopathological correlations between aspects of cognition, disease severity and imaging in Parkinson's Disease (PD) have been unclear. We studied cognitive profiles, demographics, and functional connectivity patterns derived from resting-state fMRI data (rsFC) in 31 PD subjects from the Parkinson's Progression Markers Initiative (PPMI) database. We also examined rsFC from 19 healthy subjects (HS) from the Pacific Parkinson's Research Centre. Graph theoretical measures were used to summarize the rsFC patterns. Canonical correlation analysis (CCA) was used to relate separate cognitive profiles in PD that were associated with disease severity and demographic measures as well as rsFC network measures. The CCA model relating cognition to demographics suggested female gender and education supported cognitive function in PD, age and depression scores were anti-correlated with overall cognition, and UPDRS had little influence on cognition. Alone, rsFC global network measures did not significantly differ between PD and controls, yet some nodal network measures, such as network segregation, were distinguishable between PD and HS in cortical “hub” regions. The CCA model relating cognition to rsFC global network values, which was not related to the other CCA model relating cognition to demographic information, suggested modularity, rich club coefficient, and transitivity was also broadly related to cognition in PD. Our results suggest that education, aging, comorbidity, and gender impact cognition more than overall disease severity in PD. Cortical “hub” regions are vulnerable in PD, and impairments of processing speed, attention, scanning abilities, and executive skills are related to enhanced functional segregation seen in PD.

Sex disparities in access to caregiving in Parkinson disease

OBJECTIVE

To compare access to caregiving between men and women with Parkinson disease (PD).

METHODS

This was a cross-sectional and longitudinal study among participants with PD enrolled in the National Parkinson Foundation Parkinson's Outcomes Project from 2009 to 2014 at 21 international sites. The primary outcome measures were presence of a caregiver at the baseline visit, caregiver burden as measured by the Multidimensional Caregiver Strain Index (MCSI) at baseline, and time to first paid caregiver.

RESULTS

A total of 7,209 participants (63% men, 37% women) with PD were evaluated. Men had a mean age of 66.0 (SD 9.8) years, and women had a mean age of 66.9 (SD 9.7) years. More men than women had a caregiver (88.4% vs 79.4%, p < 0.0001). Caregivers of men reported greater strain than those of women (MCSI score 19.9 vs 16.4, p < 0.0001). These differences persisted after controlling for age, disease stage, number of comorbidities, cognitive and mobility measures, and health-related quality of life. In addition, the odds of caregiver accompaniment at baseline visit were lower for women compared to men (odds ratio 0.76, 95% confidence interval [CI] 0.67-0.86), and women had a faster rate to using a paid caregiver than men (hazard ratio 1.76, 95% CI 1.35-2.28) after controlling for potential confounders.

CONCLUSIONS

Informal caregiving resources are lower for women than men with PD, despite the finding that their caregivers report less strain than those of men. In addition, women are more likely to use formal, paid caregivers. Strategies to improve access to caregiving, particularly for women, are needed.

Gender differences in Parkinson's disease: A clinical perspective

Available data indicate that there are gender differences in many features of Parkinson's disease (PD). Precise identification of the gender differences is important to tailor treatment, predict outcomes, and meet other individual and social needs in women and men with PD. The aim of this study was to review the available clinical data on gender differences in PD. Original articles and meta-analyses published between 1990 and 2016 systematically exploring gender differences in PD were reviewed. There is slight male preponderance in incidence and prevalence of PD. PD starts earlier in men. Women tend to be more prone to develop tremor-dominant PD but are less rigid than men. Motor improvement after deep brain stimulation is equal in both sexes, but women tend to show better improvement in activities of daily living. Furthermore, women with PD show better results on tests for general cognitive abilities, outperform men in verbal cognitive tasks, show more pain symptoms, and score higher on depression scales. It seems, however, that the differences in cognition, mood, and pain perception are not disease specific as similar gender differences can be found in healthy subjects and in other neurological conditions. Despite PD being the most frequently studied movement disorder, studies investigating gender differences in PD are still scarce with most of the studies being cross-sectional. Good-quality, prospective, longitudinal studies analyzing gender differences in PD and comparing them to matched healthy controls are needed in order to properly address the issues of gender differences in PD.

Considering sex and gender in Alzheimer disease and other dementias

Suffering related to dementia is multifaceted because cognitive and physical functioning slowly deteriorates. Advanced age and sex, two of the most prominent risk factors for dementia, are not modifiable. Lifestyle factors such as smoking, excessive alcohol use, and poor diet modulate susceptibility to dementia in both males and females. The degree to which the resulting health conditions (eg, obesity, type 2 diabetes, and cardiovascular disease) impact dementia risk varies by sex. Depending on the subtype of dementia, the ratio of male to female prevalence differs. For example, females are at greater risk of developing Alzheimer disease dementia, whereas males are at greater risk of developing vascular dementia. This review examines sex and gender differences in the development of dementia with the goal of highlighting factors that require further investigation. Considering sex as a biological variable in dementia research promises to advance our understanding of the pathophysiology and treatment of these conditions.

Sexual dimorphism in Parkinson's disease: differences in clinical manifestations, quality of life and psychosocial functioning between males and females

INTRODUCTION

Sex-related differences in clinical manifestations and consequences of Parkinson's disease (PD) have been poorly explored. Better understanding of sexual dimorphism in neurologic diseases such as PD has been announced as a research priority. The aim of our study was to determine independent sex differences in clinical manifestations and subtypes, psychosocial functioning, quality of life (QoL) and its domains between male and female individuals with PD.

PATIENTS AND METHODS

A comprehensive list of demographics, motor symptoms and subtypes, nonmotor features, health-related quality of life (HRQoL), psychosocial functioning and general aspects of daily life was assessed in 157 individuals (108 males and 49 females) with idiopathic PD. In order to control for potential confounding variables, we applied Orthogonal Partial Least Squares - Discriminant Analysis (OPLS-DA) to explore the strength of each feature to discriminate male and female patients with PD.

RESULTS

While no sex difference was found in the total Unified Parkinson's Disease Rating Scale (UPDRS) score and cumulative daily dose of levodopa, females had significantly more severe anxiety (mean difference =2.2 [95% confidence interval, CI: 0.5-4.0], P=0.011), worse nutritional status (23.8 [standard deviation, SD =4.2] vs 25.8 [SD =2.6], P=0.003) and poorer QoL (28.3 [SD =15.7] vs 17.9 [SD =14.2], P<0.001). Based on multivariate discriminant analysis, emotional well-being, bodily discomfort, social support, mobility and communication domains of HRQoL, together with anxiety, depression and psychosocial functioning, were the strongest features with more severe/worse status in females after adjustment for potential statistical confounders.

CONCLUSION

Our study provides a comprehensive understanding of sexual dimorphism in PD. Anxiety, depression, specific domains of HRQoL (mobility, emotional well-being, social support and bodily discomfort) and psychosocial functioning were significantly worse in female individuals with PD. Sexual dimorphism in PD highlights the features that are more likely to be affected in each sex and should be specifically targeted when managing male and female individuals with PD.

Self-Reported Symptoms of Parkinson's Disease by Sex and Disease Duration

Parkinson's disease (PD) is a neurodegenerative disease with a wide range of symptom presentations. The purpose of this research was to compare self-reported motor and non-motor symptoms of PD by sex and disease duration. This study was a cross-sectional descriptive survey in community-dwelling people with PD. A total of 141 participants (64.6% response rate; 59.6% men; M_age = 69.7 years) were included. Males reported more rigidity, speech problems, sexual dysfunction, memory problems, and socializing problems than females. The number of motor symptoms in three groups divided by increments of 5 years was significantly increased. Postural instability, freezing, off periods, dyskinesia, speech problems, and hallucinations/psychosis were significantly increased as the disease duration increased. Thorough assessment of motor and non-motor symptoms could decrease the risk of inadequate symptom management. Provision of information regarding PD symptoms at each stage may help people with PD and their caregivers in planning their future care and life.

Statin therapy prevents the onset of Parkinson disease in patients with diabetes

OBJECTIVE

We studied the association between the statin dosage and the risk of Parkinson disease (PD) in diabetic patients in Taiwan.

METHODS

One million patients were randomly sampled from a National Health Insurance (NHI) database and followed from 2001 to 2008. Diabetic patients were screened by diagnosis of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes, and statin dosage was determined according to the NHI pharmacy database. PD was diagnosed on the basis of ICD-9-CM codes and anti-Parkinson medication use. Statin users was classified by statin dose-duration-day > 28 and matched with nonusers of statins using a coarsened exact matching method. There were 50,432 patients, and half of them were statin users. We examined the risk of PD between statin users and nonusers of statins and further tested the trends of the relative risk between the statin dosage and PD.

RESULTS

The PD incidence rate was lower in statin users than in nonusers of statins. The crude hazard ratio of PD incidence in statin users was 0.65 (95% confidence interval [CI] = 0.57-0.74) in females and 0.60 (95% CI = 0.51-0.69) in males compared with nonusers of statins. After Cox regression analysis, all statins except lovastatin exerted protective effects on PD incidence and had a significant dose-dependent trend.

INTERPRETATION

In Taiwanese diabetic patients, the risk of PD is lower in statin users than in nonusers of statins. Statin users, except lovastatin users, are dose-dependently associated with a decreased incidence of PD compared with nonusers of statins. This finding provides a new indication for statin beyond lipid control and cardiovascular events in diabetic patients. Ann Neurol 2016;80:532-540.

Sex Differences in the Clinical Progression of Parkinson's Disease

OBJECTIVE

To describe characteristics of Parkinson's disease by sex and determine if differences in disease progression exist.

DESIGN

Longitudinal, observational study.

SETTING

Twenty-one National Parkinson Foundation Centers of Excellence.

PARTICIPANTS

People (N = 4,679; 63% men and 37% women) with idiopathic Parkinson's disease.

METHODS

Demographic and clinical data at enrollment and after 1 year were collected. We defined progression as a 1-year change in the following functional health outcome measures: (a) health-related quality of life (Parkinson's Disease Questionnaire-39), (b) Timed Up and Go test, (c) cognitive function, and (d) number of medications. We compared baseline characteristics between men and women. Then, linear regression models were built to assess the independent contribution of sex to progression.

RESULTS

At baseline, women were significantly more likely to be older and have greater disease severity and more comorbidities than men despite similar duration of disease. This finding corresponded to worse function as assessed by the Parkinson's Disease Questionnaire-39 and Timed Up and Go test but not to number of medications and cognitive function. After 1 year, declines across all functional measures except delayed recall occurred. No significant changes in Parkinson's Disease Questionnaire-39, Timed Up and Go, number of medications, or verbal fluency between men and women occurred. Women had a more significant improvement in delayed recall than men.

CONCLUSION

Numerous small baseline differences occurred between men and women with PD, although differences in markers of progression were few. Findings suggest that clinical manifestations and prognosis appear similar by sex under the same treatment conditions.

Impact of Sex on the Nonmotor Symptoms and the Health-Related Quality of Life in Parkinson's Disease

Background. Female Parkinson's disease (PD) patients seem to experience not only more severe motor complications and postural instability but also more pronounced depression, anxiety, pain, and sleep disturbances. Objective. The aim of the present study was to evaluate the role of sex as a possible independent predictor of HRQoL in PD. Methods. In this cross-sectional study, 621 consecutive patients treated at the University of Pécs were enrolled. Severity of PD symptoms was assessed by MDS-UPDRS, UDysRS, Non-Motor Symptoms Scale, PDSS-2, Hamilton Anxiety Scale, Montgomery-Asberg Depression Rating Scale, Lille Apathy Rating Scale, and Addenbrooke Cognitive Examination. HRQoL was assessed by PDQ-39 and EQ-5D. Multiple regression analysis was performed to estimate the PDQ-39 and EQ-5D index values based on various clinical factors. Results. Although females received significantly lower dosage of levodopa, they had significantly more disabling dyskinesia and worse postural instability. Anxiety, pain, sleep disturbances, and orthostatic symptoms were more frequent among females while sexual dysfunction, apathy, and daytime sleepiness were more severe among males. Women had worse HRQoL than men (EQ-5D index value: 0.620 ± 0.240 versus 0.663 ± 0.229, p = 0.025, and PDQ-39 SI: 27.1 ± 17.0 versus 23.5 ± 15.9, p = 0.010). Based on multiple regression analysis, sex was an independent predictor for HRQoL in PD. Conclusions. Based on our results, female sex is an independent predictor for having worse HRQoL in PD.

Functional Performance and Associations between Performance Tests and Neurological Assessment Differ in Men and Women with Parkinson's Disease

BACKGROUND

Neurological assessment of a patient with Parkinson's disease (PD) is expected to reflect upon functional performance. As women are known to report more limitations even for same observed functional performance level, present study was designed to examine whether associations between neurological assessments and functional performance differ across genders.

METHODS

14 men and 14 women with PD participated. Functional performance was assessed by measuring walking speeds on 10-meter walk test (10MWT) and by performing timed-up-and-go-test (TUG). Neurological assessment included Hoehn and Yahr Scale (HY), Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Schwab and England Activities of Daily Living Scale (S-E), and Mini Mental State Examination (MMSE).

RESULTS

In women with PD, Kendall's tau-b correlation analyses revealed significant correlations between functional performance tests and neurological assessment measures, with the exception in MMSE. No corresponding associations were found for men, although they demonstrated better functional performance, as expected.

CONCLUSION

Men in similar clinical stage of the PD perform better on functional tests than women. Disease severity reflects upon functional performance differently in men and women with PD. Results indicate that when interpreting the assessment results of both functional performance and neurological assessment tests, the gender of the patient should be taken into consideration.