Effect of age at onset on progression and mortality in Parkinson's disease

Safety, tolerability, and efficacy of NLY01 in early untreated Parkinson's disease: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Converging lines of evidence suggest that microglia are relevant to Parkinson's disease pathogenesis, justifying exploration of therapeutic agents thought to attenuate pathogenic microglial function. We sought to test the safety and efficacy of NLY01-a brain-penetrant, pegylated, longer-lasting version of exenatide (a glucagon-like peptide-1 receptor agonist) that is believed to be anti-inflammatory via reduction of microglia activation-in Parkinson's disease.

METHODS

We report a 36-week, randomised, double-blind, placebo-controlled study of NLY01 in participants with early untreated Parkinson's disease conducted at 58 movement disorder clinics in the USA. Participants meeting UK Brain Bank or Movement Disorder Society research criteria for Parkinson's disease were randomly allocated (1:1:1) to one of two active treatment groups (2·5 mg or 5·0 mg NLY01) or matching placebo, based on a central computer-generated randomisation scheme using permuted block randomisation with varying block sizes. All participants, investigators, coordinators, study staff, and sponsor personnel were masked to treatment assignments throughout the study. The primary efficacy endpoint for the primary analysis population (defined as all randomly assigned participants who received at least one dose of study drug) was change from baseline to week 36 in the sum of Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) parts II and III. Safety was assessed in the safety population (all randomly allocated participants who received at least one dose of the study drug) with documentation of adverse events, vital signs, electrocardiograms, clinical laboratory assessments, physical examination, and scales for suicidality, sleepiness, impulsivity, and depression. This trial is complete and registered at ClinicalTrials.gov, NCT04154072.

FINDINGS

The study took place between Jan 28, 2020, and Feb 16, 2023. 447 individuals were screened, of whom 255 eligible participants were randomly assigned (85 to each study group). One patient assigned to placebo did not receive study treatment and was not included in the primary analysis. At 36 weeks, 2·5 mg and 5·0 mg NLY01 did not differ from placebo with respect to change in sum scores on MDS-UPDRS parts II and III: difference versus placebo -0·39 (95% CI -2·96 to 2·18; p=0·77) for 2·5 mg and 0·36 (-2·28 to 3·00; p=0·79) for 5·0 mg. Treatment-emergent adverse events were similar across groups (reported in 71 [84%] of 85 patients on 2·5 mg NLY01, 79 [93%] of 85 on 5·0 mg, and 73 [87%] of 84 on placebo), with gastrointestinal disorders the most commonly observed class in active groups (52 [61%] for 2·5 mg, 64 [75%] for 5·0 mg, and 30 [36%] for placebo) and nausea the most common event overall (33 [39%] for 2·5 mg, 49 [58%] for 5·0 mg, and 16 [19%] for placebo). No deaths occurred during the study.

INTERPRETATION

NLY01 at 2·5 and 5·0 mg was not associated with any improvement in Parkinson's disease motor or non-motor features compared with placebo. A subgroup analysis raised the possibility of motor benefit in younger participants. Further study is needed to determine whether these exploratory observations are replicable.

FUNDING

D&D Pharmatech-Neuraly.

The long-term trend of Parkinson’s disease incidence and mortality in China and a Bayesian projection from 2020 to 2030

Background: Parkinson’s disease is a disabling degenerative disease of the central nervous system that occurs mainly in elderly people. The changes in the incidence and mortality of Parkinson’s disease at the national level in China over the past three decades have not been fully explored.

Methods: Research data were obtained from the Global Burden of Disease 2019 study. The trends of crude and age-standardized incidence and mortality rates by gender of Parkinson’s disease in China were analyzed with the age-period-cohort model and the Joinpoint regression analysis. The effects of age, time period, and birth cohort on the incidence and mortality of Parkinson’s disease were estimated. The gender- and age-specific incidence and mortality rates of Parkinson’s disease from 2020 to 2030 were projected using the Bayesian age-period-cohort model with integrated nested Laplace approximations.

Results: From 1990 to 2019, the annual percentage change of the age-standardized incidence rate was 0.8% (95% CI: 0.7%–0.8%) for males and 0.2% (95% CI, 0.2–0.2%) for females. And the age-standardized mortality rate for males was 2.9% (95% CI: 2.6%–3.2%) and 1.8% (95% CI: 1.5%–2.1%) for females. The results of the age-period-cohort analysis suggested that the risk and burden of Parkinson’s disease continued to increase for the last several decades. Projection analysis suggested that the overall Parkinson’s disease incidence will continue to increase for the next decades. It was projected that China would have 4.787 million Parkinson’s patients by the year 2030, however, the mortality of Parkinson’s disease for both genders in China may keep decreasing.

Conclusion: Though the mortality risk may decrease, Parkinson’s disease continues to become more common for both genders in China, especially in the senior-aged population. The burden associated with Parkinson’s disease would continue to grow. Urgent interventions should be implemented to reduce the burden of Parkinson’s disease in China.

Impact of age at onset on symptom profiles, treatment characteristics and health-related quality of life in Parkinson's disease

Parkinson’s disease (PD) is typically considered an age-related disease, but the age at disease onset can vary by decades between patients. Aging and aging-associated diseases can affect the movement system independently of PD, and advanced age has previously been proposed to be associated with a more severe PD phenotype with accelerated progression. In this work, we investigated how interactions between PD progression and aging affect a wide range of outcomes related to PD motor and nonmotor symptoms as well as Health Related Quality of Life (HRQoL) and treatment characteristics. This population-based cohort study is based on 1436 PD patients from southern Sweden followed longitudinally for up to approximately 7.5 years from enrollment (3470 visits covering 2285 patient years, average follow-up time 1.7 years). Higher age at onset was generally associated with faster progression of motor symptoms, with a notable exception of dyskinesia and other levodopa-associated motor fluctuations that had less severe trajectories for patients with higher age at onset. Mixed results were observed for emergence of non-motor symptoms, while higher age at onset was generally associated with worse HRQoL trajectories. Accounting for these identified age-associated differences in disease progression could positively impact patient management and drug development efforts.

Profiling the most elderly parkinson's disease patients: Does age or disease duration matter?

BACKGROUND

Despite our ageing populations, elderly patients are underrepresented in clinical research, and ageing research is often separate from that of Parkinson's disease (PD). To our knowledge, no previous study has focused on the most elderly ('old-old', age ≥ 85 years) patients with PD to reveal how age directly influences PD clinical progression.

OBJECTIVE

We compared the clinical characteristics and pharmacological profiles, including complications of levodopa treatment, disease progression, disabilities, and comorbidities of the old-old with those of comparable younger ('young-old', age 60-75 years) PD patients. In addition, within the old-old group, we compared those with a short disease duration (< 10 years at the time of diagnosis) to those with a long disease duration ≥10 years to investigate whether prognosis was related to disease progression or aging.

METHODS

This single-centre, case-control study compared 60 old-old to 92 young-old PD patients, matched for disease duration. Patients in the old-old group were also divided equally (30:30) into two subgroups (short and long disease duration) with the same mean age. We compared the groups based on several clinical measures using a conditional logistic regression.

RESULTS

By study design, there were no differences between age groups when comparing disease duration, however, the proportion of men decreased with age (p = 0.002). At a comparable length of PD duration of 10 years, the old-old PD patients predominantly had significantly greater postural instability and gait disturbance (p = 0.006), higher motor scope of the Unified Parkinson's Disease Rating Scale (UPDRS-III, p<0.0001), and more advanced Hoehn & Yahr (H&Y) stage (p<0.0001). The Non-Motor Symptoms Questionnaire (NMSQuest) score was also significantly higher among the old-old (p<0.0001) compared to the young-old patients. Moreover, the distribution of NMS also differed between ages, with features of gastrointestinal problems (p<0.0001), urinary problems (p = 0.004), sleep disturbances and fatigue (p = 0.032), and cognitive impairment (p<0.0001) significantly more common in the old-old group, whereas sexual problems (p = 0.012), depression, and anxiety (p = 0.032) were more common in the young-old. No differences were found in visual hallucinations, cerebrovascular disease, and miscellaneous domains. While young-old PD patients received higher levodopa equivalent daily doses (p<0.0001) and developed a significant greater rate of dyskinesia (p = 0.002), no significant difference was observed in the rate of wearing-off (p = 0.378). Old-old patients also had greater disability, as measured by the Schwab and England scale (p<0.0001) and had greater milestone frequency specifically for dementia (p<0.0001), wheelchair placement (p<0.0001), nursing home placement (p = 0.019), and hospitalisation in the past 1 year (p = 0.05). Neither recurrent falls (p = 0.443) nor visual hallucinations (p = 0.607) were documented significantly more often in the old-old patients.

CONCLUSIONS

Age and disease duration were independently associated with clinical presentation, course, and progression of PD. Age was the main predictor, but disease duration also had a strong effect, suggesting that factors of the ageing process beyond the disease process itself cause PD in the most elderly to be more severe.

The effect of Non-Motor symptoms on Health-Related quality of life in patients with young onset Parkinson's Disease: A single center Vietnamese Cross-Sectional study

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Non-motor features may negatively impact those with young-onset Parkinson disease.

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Sleep/fatigue was the most severely affected, followed by mood/cognition.

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These domains independently predicted health-related quality of life (HRQoL).

Background

Young onset Parkinson’s disease (YOPD) is a distinct entity from typical late onset Parkinson’s disease (LOPD). The influene of non-motor features on the health - related quality of life (HRQoL) in LOPD has been previously reported, but little is known about the impact of non-motor features in YOPD.

Objective

The aim of this study was to explore the relationship between non-motor burden and HRQoL in patients with YOPD.

Methods

This was an observational, cross-sectional study in patients with a PD, whose age at disease onset ranged from 21 to 40 years (YOPD). Participants were assessed with the MDS Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), Non-Motor Symptoms Scale (NMSS) and the 39-item Parkinson’s Disease Questionnaire (PDQ-39; range 0–100). Spearman’s rank test was used to identify correlations between NMSS domains and several dimension of HRQoL. Stepwise multiple linear regression analysis was performed to identify the independent predictors of HRQoL as measured by PDQ-39 summary index.

Results

89 patients with YOPD mean (SD) age = 42.15 (5.84) participated. Patients reported 10.17 (4.74) non-motor symptoms, the most common (75%) and severe (median = 3) of which was was fatigue (IQR = 7). The most frequently reported and severely affected NMSS domain was sleep/fatigue (89.9%, median = 8; IQR = 13) followed by mood/cognition (83.1%, median = 6; IQR = 18) and attention/memory (82%, median = 5; IQR = 8). The mean (SD) summary index of PDQ-39 was 32.89 (16.8). The means (SD) of each PDQ-39 dimensions were: mobility 37.33 (21.96), ADL 42.93 (25.33), emotional well-being 39.77 (25.47), stigma 38.19 (28.44), social support 19.03 (22.89), cognition 29.59 (20.63), communication 26.96 (23.57), and bodily discomfort 29.96 (23.19). With the exception of gastrointestinal tract and sexual function, all other NMSS domain scores were correlated with the PDQ-39 summary index. The multivariate model revealed that three NMSS domains including sleep/fatigue, mood/cognition and attention/memory accompanied with UPDRS part III were independent predictors of HRQoL as measured by PDQ-39SI.

Conclusions

Non-motor symptoms pertaining to sleep disturbances/fatigue, mood/cognition and attention/memory negatively impact HRQoL in patients with YOPD.

A Practical Approach to Early-Onset Parkinsonism

Early-onset parkinsonism (EO parkinsonism), defined as subjects with disease onset before the age of 40 or 50 years, can be the main clinical presentation of a variety of conditions that are important to differentiate. Although rarer than classical late-onset Parkinson’s disease (PD) and not infrequently overlapping with forms of juvenile onset PD, a correct diagnosis of the specific cause of EO parkinsonism is critical for offering appropriate counseling to patients, for family and work planning, and to select the most appropriate symptomatic or etiopathogenic treatments. Clinical features, radiological and laboratory findings are crucial for guiding the differential diagnosis. Here we summarize the most important conditions associated with primary and secondary EO parkinsonism. We also proposed a practical approach based on the current literature and expert opinion to help movement disorders specialists and neurologists navigate this complex and challenging landscape.

Increased Mortality in Young-Onset Parkinson's Disease

Objective

Few studies have followed Parkinson’s disease (PD) patients from the time of diagnosis to the date of death. This study compared mortality in the Trondheim PD cohort to the general population, investigated causes of death and analyzed the associations between mortality and age at disease onset (AAO) and cognitive decline defined as Montreal Cognitive Assessment (MoCA) score below 26.

Methods

The cohort was followed longitudinally from 1997. By the end of January 2020, 587 patients had died. Comparisons to the Norwegian population were performed by calculating standardized mortality ratios (SMRs). Survival curves were estimated using the standard Kaplan-Meier estimator, and multivariable Cox proportional hazard models were estimated to investigate associations.

Results

SMR was 2.28 [95% confidence interval (CI): 2.13–2.44] for the whole cohort. For participants with AAO 20–39 years, the SMR was 5.55 (95% CI: 3.38–8.61). Median survival was 15 years (95% CI: 14.2–15.5) for the whole cohort. Early-onset PD (EOPD) patients (AAO < 50 years) had the longest median survival time. For all groups, there was a significant shortening in median survival time and an almost 3-fold higher age- and sex-adjusted hazard ratio for death when the MoCA score decreased below 26.

Conclusion

PD patients with an AAO before 40 years had a more than fivefold higher mortality rate compared to a similar general population. EOPD patients had the longest median survival; however, their life expectancy was reduced to a greater degree than that of late-onset PD patients. Cognitive impairment was strongly associated with mortality in PD.

Individual variability in human urinary metabolites identifies age-related, body mass index-related, and sex-related biomarkers

Background

Metabolites present in human urine can be influenced by individual physiological parameters (e.g., body mass index [BMI], age, and sex). Observation of altered metabolites concentrations could provide insight into underlying disease pathology, disease prognosis and diagnosis, and facilitate discovery of novel biomarkers.

Methods

Quantitative metabolomics analysis in the urine of 183 healthy individuals was performed based on high‐resolution liquid chromatography–mass spectrometry (LC–MS). Coefficients of variation were obtained for 109 urine metabolites of all the 183 human healthy subjects.

Results

Three urine metabolites (such as dehydroepiandrosterone sulfate, acetaminophen glucuronide, and p‐anisic acid) with CV₁₈₃ > 0.3, for which metabolomics studies have been scarce, are considered highly variable here. We identified 30 age‐related metabolites, 18 BMI‐related metabolites, and 42 sex‐related metabolites. Among the identified metabolites, three metabolites were found to be associated with all three physiological parameters (age, BMI, and sex), which included dehydroepiandrosterone sulfate, 3‐methylcrotonylglycine and N‐acetyl‐aspartic acid. Pearson's coefficients demonstrated that some age‐, BMI‐, and sex‐related compounds are strongly correlated, suggesting that age, BMI, and sex could affect them concomitantly.

Conclusion

Metabolic differences between distinct physiological statuses were found to be related to several metabolic pathways (such as the caffeine metabolism, the amino acid metabolism, and the carbohydrate metabolism), and these findings may be key for the discovery of new diagnostics and treatments as well as new understandings on the mechanisms of some related diseases.

LRRK2 at the Crossroad of Aging and Parkinson's Disease

Parkinson's disease (PD) is a heterogeneous neurodegenerative disease characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta and the widespread occurrence of proteinaceous inclusions known as Lewy bodies and Lewy neurites. The etiology of PD is still far from clear, but aging has been considered as the highest risk factor influencing the clinical presentations and the progression of PD. Accumulating evidence suggests that aging and PD induce common changes in multiple cellular functions, including redox imbalance, mitochondria dysfunction, and impaired proteostasis. Age-dependent deteriorations in cellular dysfunction may predispose individuals to PD, and cellular damages caused by genetic and/or environmental risk factors of PD may be exaggerated by aging. Mutations in the LRRK2 gene cause late-onset, autosomal dominant PD and comprise the most common genetic causes of both familial and sporadic PD. LRRK2-linked PD patients show clinical and pathological features indistinguishable from idiopathic PD patients. Here, we review cellular dysfunctions shared by aging and PD-associated LRRK2 mutations and discuss how the interplay between the two might play a role in PD pathologies.

Therapy of Parkinson's Disease Subtypes

Early descriptions of subtypes of Parkinson's disease (PD) are dominated by the approach of predetermined groups. Experts defined, from clinical observation, groups based on clinical or demographic features that appeared to divide PD into clinically distinct subsets. Common bases on which to define subtypes have been motor phenotype (tremor dominant vs akinetic-rigid or postural instability gait disorder types), age, nonmotor dominant symptoms, and genetic forms. Recently, data-driven approaches have been used to define PD subtypes, taking an unbiased statistical approach to the identification of PD subgroups. The vast majority of data-driven subtyping has been done based on clinical features. Biomarker-based subtyping is an emerging but still quite undeveloped field. Not all of the subtyping methods have established therapeutic implications. This may not be surprising given that they were born largely from clinical observations of phenotype and not in observations regarding treatment response or biological hypotheses. The next frontier for subtypes research as it applies to personalized medicine in PD is the development of genotype-specific therapies. Therapies for GBA-PD and LRRK2-PD are already under development. This review discusses each of the major subtyping systems/methods in terms of its applicability to therapy in PD, and the opportunities and challenges designing clinical trials to develop the evidence base for personalized medicine based on subtypes.

A deep learning approach for prediction of Parkinson's disease progression

This paper proposes a deep neural network (DNN) model using the reduced input feature space of Parkinson's telemonitoring dataset to predict Parkinson's disease (PD) progression. PD is a chronic and progressive nervous system disorder that affects body movement. PD is assessed by using the unified Parkinson's disease rating scale (UPDRS). In this paper, firstly, principal component analysis (PCA) is employed to the featured dataset to address the multicollinearity problems in the dataset and to reduce the dimension of input feature space. Then, the reduced input feature space is fed into the proposed DNN model with a tuned parameter norm penalty (L2) and analyses the prediction performance of it in PD progression by predicting Motor and Total-UPDRS score. The model's performance is evaluated by conducting several experiments and the result is compared with the result of previously developed methods on the same dataset. The model's prediction accuracy is measured by fitness parameters, mean absolute error (MAE), root mean squared error (RMSE), and coefficient of determination (R²). The MAE, RMSE, and R² values are 0.926, 1.422, and 0.970 respectively for motor-UPDRS. These values are 1.334, 2.221, and 0.956 respectively for Total-UPDRS. Both the Motor and Total-UPDRS score is better predicted by the proposed method. This paper shows the usefulness and efficacy of the proposed method for predicting the UPDRS score in PD progression.

Genetic variability and potential effects on clinical trial outcomes: perspectives in Parkinson's disease

BACKGROUND

Classical randomisation of clinical trial patients creates a source of genetic variance that may be contributing to the high failure rate seen in neurodegenerative disease trials. Our objective was to quantify genetic difference between randomised trial arms and determine how imbalance can affect trial outcomes.

METHODS

5851 patients with Parkinson's disease of European ancestry data and two simulated virtual cohorts based on public data were used. Data were resampled at different sizes for 1000 iterations and randomly assigned to the two arms of a simulated trial. False-negative and false-positive rates were estimated using simulated clinical trials, and per cent difference in genetic risk score (GRS) and allele frequency was calculated to quantify variance between arms.

RESULTS

5851 patients with Parkinson's disease (mean (SD) age, 61.02 (12.61) years; 2095 women (35.81%)) as well as simulated patients from virtually created cohorts were used in the study. Approximately 90% of the iterations had at least one statistically significant difference in individual risk SNPs between each trial arm. Approximately 5%-6% of iterations had a statistically significant difference between trial arms in mean GRS. For significant iterations, the average per cent difference for mean GRS between trial arms was 130.87%, 95% CI 120.89 to 140.85 (n=200). Glucocerebrocidase (GBA) gene-only simulations see an average 18.86%, 95% CI 18.01 to 19.71 difference in GRS scores between trial arms (n=50). When adding a drug effect of -0.5 points in MDS-UPDRS per year at n=50, 33.9% of trials resulted in false negatives.

CONCLUSIONS

Our data support the hypothesis that within genetically unmatched clinical trials, genetic heterogeneity could confound true therapeutic effects as expected. Clinical trials should undergo pretrial genetic adjustment or, at the minimum, post-trial adjustment and analysis for failed trials.

Large-Scale Assessment of Function and Disability in Patients with Parkinson's Disease Using the Functioning Disability Evaluation Scale-Adult Version

This study assesses the functioning and disability related to Parkinson's disease using the Functioning Disability Evaluation Scale-Adult Version (FUNDES-Adult), based on the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) in a large-scale database; this study describes, discusses and clarifies the predictive factor of not being in an ambulatory status. Of 7455 patients included in this study, 3561 were not ambulatory and 3894 were ambulatory or assisted ambulatory. Patients with poor walking status revealed higher FUNDES-Adult scores in all domains. Age, modified Hoehn⁻Yahr stage, living in an institution and the standardized score of FUNDES-Adult domains 1 and 2 were positive independent predictors of the not ambulatory status. The FUNDES-Adult could evaluate multifaceted disability and predict the walking status in patients with Parkinson's disease.

Very old onset parkinsonism: A clinical-pathological study

BACKGROUND

With increasing age of the world population, the number of parkinsonian patients with disease onset in very old age is expected to increase. Information about the clinical and morphological phenotype of very old age onset parkinsonism is poor, and only three autopsy-confirmed studies of parkinsonian patients of 80 years and older onset are available.

METHODS

A retrospective autopsy study of 345 patients clinically diagnosed as Parkinson disease (PD) included 90 cases with disease onset ≥80 years).

RESULTS

Clinically, the majority (60%) presented with a rigid-akinetic phenotype, 13.3% with mixed tremor, akinesia and rigidity, 8.9% tremor-dominant type, 7.8% with tremor + rigidity, 5.6% with tremor-akinesia, and 4.4% with pure akinesia or gait disorder. Additional 8.9% developed hemiparesis, and 80% were demented. In only about 49% of the patients, positive reaction to l-dopa therapy was reported. The progress of disease was accelerated, and survival time (4.34 ± 2.95 SD) was significantly shorter than in younger onset groups. At post mortem examination, only 21 cases (23.3%) revealed Lewy body disease of brainstem type (PD) alone, 44 cases (48.9%) had PD plus Alzheimer disease (AD) (including 6 cases of Lewy body variant of AD). 11% had PD plus cerebrovascular lesions, 6 cases (6.7%) were cerebrovascular disorders and 8 cases (8.9%) were other neurodegenerative diseases (AD, single cases of multiple system atrophy, progressive supranuclear palsy).

CONCLUSION

The present and other data confirm the clinical and morphological heterogeneity of parkinsonism with shorter survival in the octogenarian population.

Weight Loss in Parkinson's Disease: The Relationship with Motor Symptoms and Disease Progression

Objectives

To determine the prevalence of weight loss (WL) in PD patients, its relationship to the severity of motor manifestations and appetite changes.

Methods

144 PD patients and 120 controls were evaluated in a single session. All subjects were asked about changes in body weight and appetite. PD patients were examined with the UPDRS-III and the Hoehn and Yahr (HY) scales. Subscores of tremor, bradykinesia /rigidity, and non-dopaminergic symptoms (NDS) were analyzed individually. Multivariable logistic regression analysis was used to determine an association between WL and PD motor manifestations.

Results

48.6 % of PD patients presented WL compared to 20.8 % of controls (p < 0.001). Weight losers were significantly older and had longer disease duration, higher scores in HY stages, UPDRS-III, and NDS-subscore. Multivariable logistic regression analysis demonstrated that WL was associated with NDS-subscore (p= 0.002; OR: 1.33) and older age (p= 0.037; OR: 1.05). Appetite in PD cases losing weight was unchanged (35.7 %), decreased (31.4 %), or even increased (32.9).

Conclusions

Our results showed that WL occurs in almost half of PD patients and it is largely the consequence of disease progression rather than involuntary movements or a decrease in food intake.

Clinical characteristics and quality of life in Chinese patients with Parkinson's disease beyond 20 years

Background The number of Parkinson's disease (PD) patients with disease duration of more than 20 years (long disease duration PD, LPD) is on the rise. Objectives This study aims to describe the clinical profiles and the quality of life (QoL) of LPD patients from a cohort of the Chinese population. Methods We compared 71 LPD subjects to 60 PD patients who died less than 20 years after the onset of PD (control PD, CPD). A regression model was constructed to assess the determinants for 20 years survival and the QoL of LPD patients. Results Compared to CPD patients, LPD patients exhibited a younger age at disease onset, higher total levodopa equivalent daily dose applications, more frequent motor complications, lower annual change in Unified PD Rating Scale (UPDRS) III score, as well as lower scores for 'sleep/fatigue' and 'mood/apathy' domains and higher score for 'sexual dysfunction' domain in the Non-Motor Symptom Scale (NMSS) (p < 0.05). Multivariate regression analyses indicated that a younger age at disease onset (OR = 0.520, 95%CI = 0.295-0.919, p = 0.024), lower annual change in UPDRS III score (OR = 0.009, 95%CI = 0.001-0.246, p = 0.005) and lower 'cardiovascular' score (OR = 0.552, 95%CI = 0.319-0.955, p = 0.034) were associated with 20-year survival, while UPDRS III (β = 0.320, p < 0.001) and NMSS (β = 0.549, p < 0.001) scores were associated with the PD Questionnaire 39 score in LPD. Conclusions The age at disease onset, rate of PD deterioration, and cardiovascular symptoms are the potential determinants for 20-year survival with PD. Both motor and non-motor disturbances contribute to the reduced QoL of LPD patients.

CSF Biomarkers and Its Associations with 18F-AV133 Cerebral VMAT2 Binding in Parkinson's Disease-A Preliminary Report

OBJECTIVE

Cerebrospinal fluid (CSF) biomarkers, such as α-synuclein (α-syn), amyloid beta peptide 1-42 (Aβ1-42), phosphorylated tau (181P) (p-tau), and total tau (t-tau), have long been associated with the development of Parkinson disease (PD) and other neurodegenerative diseases. In this investigation, we reported the assessment of CSF biomarkers and their correlations with vesicular monoamine transporter 2 (VMAT2) bindings measured with 18F-9-fluoropropyl-(+)-dihydrotetrabenazine (18F-AV133) that is being developed as a biomarker for PD. We test the hypothesis that monoaminergic degeneration was correlated with CSF biomarker levels in untreated PD patients.

METHODS

The available online data from the Parkinson's Progression Markers Initiative study (PPMI) project were collected and analyzed, which include demographic information, clinical evaluations, CSF biomarkers (α-syn, Aβ1-42, p-tau, and t-tau), 18F-AV133 brain PET, and T1 weighted MRIs. Region of interest (ROI) and voxel-wise Pearson correlation between standardized uptake value ratio (SUVR) and CSF biomarkers were calculated.

RESULTS

Our major findings are: 1) Compared with controls, CSF α-syn and tau levels decreased significantly in PD; 2) α-syn was closely correlated with Aβ1-42 and tau in PD, especially in early-onset patients; and 3) hypothesis-driven ROI analysis found a significant negative correlation between CSF Aβ1-42 levels and VMAT2 densities in post cingulate, left caudate, left anterior putamen, and left ventral striatum in PDs. CSF t-tau and p-tau levels were significantly negatively related to VMAT2 SUVRs in substantia nigra and left ventral striatum, respectively. Voxel-wise analysis showed that left caudate, parahippocampal gyrus, insula and temporal lobe were negatively correlated with Aβ1-42. In addition, superior frontal gyrus and transverse temporal gyrus were negatively correlated with CSF p-tau levels.

CONCLUSION

These results suggest that monoaminergic degeneration in PD is correlated with CSF biomarkers associated with cognitive impairment in neurodegenerative diseases including Alzheimer's disease. The association between loss of dopamine synaptic function and pathologic protein accumulations in PD indicates an important role of CSF biomarkers in PD development.

Cognitive Dysfunction in Parkinson’s Disease: The Role of Frontostriatal Circuitry

It has been known for many years that the classic motor symptoms of Parkinson’s disease are accompanied by deficits of executive function that resemble those seen after frontal lobe damage in humans. What is less clear is how different components of frontostriatal circuitry contribute to these impairments. Recently, improved methods of clinical assessment and classification, combined with novel technical approaches, such as functional neuroimaging, have led to great advances in our understanding of the fundamental mechanisms that drive frontostriatal circuitry. As a direct result, it has been possible to redefine impairments of executive function in Parkinson’s disease more precisely in terms of the specific neuropsychological, neuroanatomical, and psychopharmacological mechanisms involved.

The Profile of Long-term Parkinson's Disease Survivors with 20 Years of Disease Duration and Beyond

BACKGROUND

Parkinson's disease (PD) patients with 20 years or more survival (PD-20) are not well characterized.

OBJECTIVE

To evaluate PD-20 patient characteristics and identify areas for improvement of their health care.

METHODS

The international, multicenter National Parkinson's Foundation Quality Improvement Initiative (NPF-QII) study database was queried to identify PD-20 subjects. Demographic and clinical data were analyzed.

RESULTS

We identified 187 PD-20 subjects (55% men) representing 4% (187/4,619) of all NPF-QII participants. Subjects were mean age 69.5 years; mean age at PD onset was 44.0 years. The majority (75% ) had 20-25 years of PD duration, the longest duration being 49 years. They were median Hoehn and Yahr stage 3, and 75% had motor fluctuations. Half (54% ) reported exercising. The majority (89% ) were living at home and required a caregiver (88% ). They were mildly cognitively impaired for age (Montreal Cognitive Assessment estimate 22.6±3.7), with most deficits in verbal fluency and delayed recall. Quality of life (Parkinson's Disease Quality of Life Questionnaire index 36±15% ) was mild to moderately impaired, with most impairment in mobility and activities of daily living. Caregiver strain measured by the Multidimensional Caregiver Strain Index (27±16% ), recorded highest subscores in social constraint. PD-20 subjects aged <70 years versus ≥70 only differed significantly by worse cognition (P <  0.0001).

CONCLUSIONS

PD-20 subjects reflect an elite group of PD survivors with early-onset disease and relatively mild cognitive disability despite long disease duration. Interventions for caregivers, mobility, and activities of daily living are areas that could improve caregiver burden and patient quality of life.

The association between symptoms of sexual dysfunction and age at onset in Parkinson's disease

OBJECTIVE

Age at onset in Parkinson's disease (PD) seems to be related nonmotor symptoms. In this study we investigated the effect of the age at onset on symptoms of sexual dysfunction (SSD) in patients with PD.

METHODS

This prospective study comprised 22 consecutive outpatients with early onset PD (EOPD-onset of the disease before 55 years), and 66 outpatients with late onset PD (LOPD-onset of PD over 55 years). They were all recruited from the Department of Movement Disorders, Clinic of Neurology. The diagnosis was established according to the UK PD Brain Bank Criteria by a movement disorders specialist. The Unified PD Rating Scale (UPDRS) motor was used to assess motor disability and Hoehn and Yahr (H&Y) stage was used to establish disease severity. The sexual functions of the patients were rated by applying the Arizona Sexual Experiences Scale (ASEX).

RESULTS

Thirteen EOPD patients (59.09 %) and 53 of the LOPD patients (80.3 %) (p 0.047) reported dissatisfaction with at least one item of ASEX. There were no differences between H&Y stages (p 0.205) UPDRS total (p 0.267) and motor scores (p 0.100) between groups. LOPD patients had significantly higher ASEX scores than EOPD patients (p 0.001).

INTERPRETATION

Sexual dysfunciton occurs more frequently and more severely in LOPD than EOPD patients. PD patients with different ages at onset clinically present differently in terms of SSD.

Mortality in levodopa-treated Parkinson's disease

Parkinson's disease (PD) is associated with increased mortality despite many advances in treatment. Following the introduction of levodopa in the late 1960's, many studies reported improved or normalized mortality rates in PD. Despite the remarkable symptomatic benefits provided by levodopa, multiple recent studies have demonstrated that PD patients continue to die at a rate in excess of their peers. We undertook this retrospective study of 211 deceased PD patients to determine the factors associated with mortality in levodopa-treated PD. Our findings confirm that PD is associated with increased mortality in both men and women. Unlike the majority of other mortality studies, we found that women have a greater reduction in lifespan compared to men. We also found that patients with early onset PD (onset at the age of 50 or before) have reduced survival relative to PD patients with later ages of onset. A final important finding is that survival is equal in PD patients treated with levodopa early (within 2 years or less of PD onset) versus later.

The mouse age phenome knowledgebase and disease-specific inter-species age mapping

Background

Similarities between mice and humans lead to generation of many mouse models of human disease. However, differences between the species often result in mice being unreliable as preclinical models for human disease. One difference that might play a role in lowering the predictivity of mice models to human diseases is age. Despite the important role age plays in medicine, it is too often considered only casually when considering mouse models.

Methods

We developed the mouse-Age Phenotype Knowledgebase, which holds knowledge about age-related phenotypic patterns in mice. The knowledgebase was extensively populated with literature-derived data using text mining techniques. We then mapped between ages in humans and mice by comparing the age distribution pattern for 887 diseases in both species.

Results

The knowledgebase was populated with over 9800 instances generated by a text-mining pipeline. The quality of the data was manually evaluated, and was found to be of high accuracy (estimated precision >86%). Furthermore, grouping together diseases that share similar age patterns in mice resulted in clusters that mirror actual biomedical knowledge. Using these data, we matched age distribution patterns in mice and in humans, allowing for age differences by shifting either of the patterns. High correlation (r²>0.5) was found for 223 diseases. The results clearly indicate a difference in the age mapping between different diseases: age 30 years in human is mapped to 120 days in mice for Leukemia, but to 295 days for Anemia. Based on these results we generated a mice-to-human age map which is publicly available.

Conclusions

We present here the development of the mouse-APK, its population with literature-derived data and its use to map ages in mice and human for 223 diseases. These results present a further step made to bridging the gap between humans and mice in biomedical research.

Redefining meaningful age groups in the context of disease

Age is an important factor when considering phenotypic changes in health and disease. Currently, the use of age information in medicine is somewhat simplistic, with ages commonly being grouped into a small number of crude ranges reflecting the major stages of development and aging, such as childhood or adolescence. Here, we investigate the possibility of redefining age groups using the recently developed Age-Phenome Knowledge-base (APK) that holds over 35,000 literature-derived entries describing relationships between age and phenotype. Clustering of APK data suggests 13 new, partially overlapping, age groups. The diseases that define these groups suggest that the proposed divisions are biologically meaningful. We further show that the number of different age ranges that should be considered depends on the type of disease being evaluated. This finding was further strengthened by similar results obtained from clinical blood measurement data. The grouping of diseases that share a similar pattern of disease-related reports directly mirrors, in some cases, medical knowledge of disease-age relationships. In other cases, our results may be used to generate new and reasonable hypotheses regarding links between diseases.

Comparative study of Parkinson's disease and leucine-rich repeat kinase 2 p.G2019S parkinsonism

Parkinson disease is a progressive neurodegenerative disease for which leucine-rich repeat kinase 2 (LRRK2 carriers) p.G2019S confers substantial genotypic and population attributable risk. With informed consent, we have recruited clinical data from 778 patients from Tunisia (of which 266 have LRRK2 parkinsonism) and 580 unaffected subjects. Motor, autonomic, and cognitive assessments in idiopathic Parkinson disease and LRRK2 patients were compared with regression models. The age-associated cumulative incidence of LRRK2 parkinsonism was also estimated using case-control and family-based designs. LRRK2 parkinsonism patients had slightly less gastrointestinal dysfunction and rapid eye movement sleep disorder. Overall, disease penetrance in LRRK2 carriers was 80% by 70 years but women become affected a median 5 years younger than men. Idiopathic Parkinson disease patients with younger age at diagnosis have slower disease progression. However, age at diagnoses does not predict progression in LRRK2 parkinsonism. LRRK2 p.G2019S mutation is a useful aid to diagnosis and modifiers of disease in LRRK2 parkinsonism may aid in developing therapeutic targets.

The heterogeneity of cognitive symptoms in Parkinson's disease: a meta-analysis

Several studies have reported heterogeneity in cognitive symptoms associated with specific characteristics of patients with Parkinson's disease (PD). Indeed, researchers have characterised subtypes of patients suffering from PD according to various criteria. Those most frequently used are the type of predominant motor symptoms (tremors or non-tremor symptoms), age at onset and presence of depression. Some characteristics, like the predominant motor subtypes, as well as the presence of depression, are more widely used to categorise cognitive differences between patients. The goal of this study was to analyse the impact of the type of predominant motor symptoms and depression on cognition in PD. A meta-analysis of 27 studies (from 1989 to 2012) was carried out to calculate the average effect size of these factors on the most often used cognitive test during those past years to evaluate cognitive skills, the Mini-Mental State Examination. The studies analysed showed significant mean weighted effect sizes on cognition for the type of motor symptoms (d=0.42; 95% CI 0.30 to 0.54) and for depression (d=0.52; 95% CI 0.38 to 0.66). These results suggested that PD participants with non-tremor predominant motor symptoms or with depression had more or more severe cognitive impairments. Identification of different subtypes in PD is important for a better understanding of the cognitive symptoms associated with this disease. Better knowing the impact of different features of PD subgroups could help to design more appropriate treatments for patients with PD.

Age at onset influences neurodegenerative processes underlying PD with levodopa-induced dyskinesias

PURPOSE

Recently, we demonstrated that PD patients with levodopa-induced dyskinesias are characterized by neuroanatomical and functional changes involving the prefrontal cortex. When compared with non-dyskinetic PD patients, dyskinetic PD patients showed increased volume of the inferior frontal cortex and a dysfunctional imbalance between this region and the supplementary motor area during motor task. In the current study, we investigated the impact of age at onset of the disease on the neuroanatomical characteristics of dyskinetic patients, because it is well known that early-onset PD patients usually develop dyskinesias sooner with respect to late-onset PD.

METHODS

Whole-brain voxel-wise investigations of gray matter volume and cortical thickness were carried out in dyskinetic (n = 33), non-dyskinetic PD patients (n = 33) and in age-sex-matched healthy controls (n = 40). Neuroimaging analyses were performed separately according to the age at onset (early < 50 y > late).

RESULTS

Independent of age at onset, dyskinetic PD patients showed altered morphology in the inferior frontal cortex when compared with non-dyskinetic patients. Moreover, additional significant abnormalities emerged in the early- and late-onset PD patients when compared to controls. In fact, early-onset dyskinetic patients showed increased volume in a large cluster of the midbrain encompassing substantia nigra and red nucleus, whereas late-onset dyskinetic patients were characterized by abnormal gray matter increase in the supplementary motor area.

DISCUSSION

Our findings demonstrate different patterns of brain abnormalities in patients with LID according to age at onset, highlighting the role of the nigral pathology in early-onset and of the cortical pathology in late-onset patients with PD.

Drug-induced dyskinesia in Parkinson's disease. Should success in clinical management be a function of improvement of motor repertoire rather than amplitude of dyskinesia?

BACKGROUND

Dyskinesia, a major complication in the treatment of Parkinson's disease (PD), can require prolonged monitoring and complex medical management.

DISCUSSION

The current paper proposes a new way to view the management of dyskinesia in an integrated fashion. We suggest that dyskinesia be considered as a factor in a signal-to-noise ratio (SNR) equation where the signal is the voluntary movement and the noise is PD symptomatology, including dyskinesia. The goal of clinicians should be to ensure a high SNR in order to maintain or enhance the motor repertoire of patients. To understand why such an approach would be beneficial, we first review mechanisms of dyskinesia, as well as their impact on the quality of life of patients and on the health-care system. Theoretical and practical bases for the SNR approach are then discussed.

SUMMARY

Clinicians should not only consider the level of motor symptomatology when assessing the efficacy of their treatment strategy, but also breadth of the motor repertoire available to patients.

Age of onset: can we rely on essential tremor patients to report this? Data from a prospective, longitudinal study

BACKGROUND

Essential tremor (ET) is among the most prevalent neurological diseases. Age of onset, a key variable in neuroepidemiological and genetic research, is chiefly assessed by self-report rather than medical record review; the latter may be of little use. As a researcher, one wonders about the quality of this self-report. Is age of onset something which can be reproducibly self-reported by patients? There are few published data to aid researchers.

METHODS

Age of onset was self-reported at two time points (baseline and follow-up) in 86 ET cases in a longitudinal epidemiological study in New York.

RESULTS

The mean follow-up interval was 5.7 ± 2.5 (maximum = 14) years. Overall, agreement between the baseline and follow-up reports was high (ρ = 0.85, p < 0.001). Yet the difference (age of onset (baseline) - age of onset (follow-up)) ranged widely (from -47 to 32 years), and in one fifth of cases was ≥ 10 years. Greater agreement was associated with several clinical factors including age, medication use, embarrassment, depressive symptoms, cognitive test score and disease duration.

CONCLUSIONS

Differences in reported age of onset in ET may vary widely, and in up to one fifth of patients may be substantial. Investigators should approach these self-reports with caution.

The age-phenome database

Data linking specific ages or age ranges with disease are abundant in biomedical literature. However, these data are organized such that searching for age-phenotype relationships is difficult. Recently, we described the Age-Phenome Knowledge-base (APK), a computational platform for storage and retrieval of information concerning age-related phenotypic patterns. Here, we report that data derived from over 1.5 million human-related PubMed abstracts have been added to APK. Using a text-mining pipeline, 35,683 entries which describe relationships between age and phenotype (such as disease) have been introduced into the database. Comparing the results to those obtained by a human reader reveals that the overall accuracy of these entries is estimated to exceed 80%. The usefulness of these data for obtaining new insight regarding age-disease relationships is demonstrated using clustering analysis, which is shown to capture obvious, as well as potentially interesting relationships between diseases. In addition, a new tool for browsing and searching the APK database is presented. We thus present a unique resource and a new framework for studying age-disease relationships and other phenotypic processes.

Staging neurodegenerative disorders: structural, regional, biomarker, and functional progressions

The notion of staging in the neurodegenerative disorders is modulated by the constant and progressive loss of several aspects of brain structural integrity, circuitry, and neuronal processes. These destructive processes eventually remove individuals' abilities to perform at sufficient and necessary functional capacity at several levels of disease severity. The classification of (a) patients on the basis of diagnosis, risk prognosis, and intervention outcome, forms the basis of clinical staging, and (b) laboratory animals on the basis of animal model of brain disorder, extent of insult, and dysfunctional expression, provides the components for the clinical staging and preclinical staging, respectively, expressing associated epidemiological, biological, and genetic characteristics. The major focus of clinical staging in the present account stems from the fundamental notions of Braak staging as they describe the course and eventual prognosis for Alzheimer's disease, Lewy Body dementia, and Parkinson's disease. Mild cognitive impairment, which expresses the decline in episodic and semantic memory performance below the age-adjusted normal range without marked loss of global cognition or activities of daily living, and the applications of longitudinal magnetic resonance imaging, major instruments for the monitoring of either disease progression in dementia, present important challenges for staging concepts. Although Braak notions present the essential basis for further developments, current staging conceptualizations seem inadequate to comply with the massive influx of information dealing with neurodegenerative processes in brain, advanced both under clinical realities, and discoveries in the laboratory setting. The contributions of various biomarkers of disease progression, e.g., amyloid precursor protein, and neurotransmitter system imbalances, e.g., dopamine receptor supersensitivity and interactive propensities, await their incorporation into the existing staging models thereby underlining the ongoing, dynamic feature of the staging of brain disorders.

The effect of age on motor deficits and cerebral glucose metabolism of Parkinson's disease

BACKGROUND

No systematic study has been made to separate age-related clinical deterioration and dysfunctional brain areas from those associated with Parkinson's disease (PD).

METHODS

This study included 73 de novo patients with PD and 43 age-matched controls. All subjects underwent [(18)F]-fluorodeoxy glucose (FDG) positron emission tomography studies. The severity of parkinsonian motor deficit was measured using unified PD rating scale (UPDRS) motor scores. Multiple linear regression analysis was used to identify those parkinsonian motor deficits for which severity was correlated with the age of the patients and to locate brain areas in which normalized FDG uptake values were inversely correlated with the age of the subjects.

RESULTS

Patient age was positively correlated with total UPDRS motor scores and with subscores for bradykinesia and axial motor deficits, but not with subscores for tremor and rigidity. In the control group, an age-related decline in glucose uptake was found only in the cingulate cortex. However, in the patient group, an inverse correlation between age and glucose uptake was observed in the prefrontal, cingulate, orbitofrontal, perisylvian areas, caudate, and thalamus.

CONCLUSIONS

In PD, widespread age-related decline in cerebral function may exaggerate the deterioration associated with bradykinesia and the axial motor deficits associated with nigral neuronal loss.

Towards an Age-Phenome Knowledge-base

Background

Currently, data about age-phenotype associations are not systematically organized and cannot be studied methodically. Searching for scientific articles describing phenotypic changes reported as occurring at a given age is not possible for most ages.

Results

Here we present the Age-Phenome Knowledge-base (APK), in which knowledge about age-related phenotypic patterns and events can be modeled and stored for retrieval. The APK contains evidence connecting specific ages or age groups with phenotypes, such as disease and clinical traits. Using a simple text mining tool developed for this purpose, we extracted instances of age-phenotype associations from journal abstracts related to non-insulin-dependent Diabetes Mellitus. In addition, links between age and phenotype were extracted from clinical data obtained from the NHANES III survey. The knowledge stored in the APK is made available for the relevant research community in the form of 'Age-Cards', each card holds the collection of all the information stored in the APK about a particular age. These Age-Cards are presented in a wiki, allowing community review, amendment and contribution of additional information. In addition to the wiki interaction, complex searches can also be conducted which require the user to have some knowledge of database query construction.

Conclusions

The combination of a knowledge model based repository with community participation in the evolution and refinement of the knowledge-base makes the APK a useful and valuable environment for collecting and curating existing knowledge of the connections between age and phenotypes.

Treatment of young-onset Parkinson's disease: role of dopamine receptor agonists

For mostly arbitrary reasons, the term "juvenile parkinsonism" is restricted to patients aged 20 years or younger, and "young-onset PD" (YOPD) is onset between ages 21 and 40 years. Previous studies suggest that YOPD has a slower disease progression and a greater incidence and earlier appearance of L-dopa-induced dyskinesias and motor fluctuations. Therefore, our therapeutic strategies have to respect the fact that YOPD patients face many years of gradual progression of disease and disability, a greater probability for developing various adverse effects of treatment, and worsening of quality of life. As an individually tailored treatment should be our primary goal, we must bear in mind that the needs and expectations of YOPD patients are different from those of their older counterparts. The therapeutic strategy for YOPD patients should include a relatively low threshold for initiation of treatment, and initiating treatment with a dopamine receptor agonist while maintaining an individually adjusted, moderately high threshold for switching to or adding L-dopa in cases where treatment response is suboptimal or if problematic adverse effects develop. It has been shown that some dopamine receptor agonists may also have antidepressive efficacy, thus potentially managing an additional problem associated with PD.

Predictive factors affecting early deterioration of axial symptoms after subthalamic nucleus stimulation in Parkinson's disease

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment option for medically refractory Parkinson's disease (PD). However, some patients show deterioration of axial symptoms within a short time after surgery. We studied 43 patients who underwent bilateral STN-DBS and investigated predictive factors affecting early deterioration of axial symptoms. Among 43 patients, 16 patients showed obvious deterioration of axial symptoms within three years of surgery. Multiple logistic regression analysis indicated that the significant independent variables related to early deterioration of axial symptoms were rapidly progressive short duration of the disease and advanced age at surgery. These results suggest that patients with rapidly progressing PD, who need early surgical intervention, tend to show early deterioration of axial symptoms after STN-DBS.

Sleep disturbances in Parkinson disease and their potential role in heterogeneity

Parkinson disease (PD) is commonly conceptualized as a movement disorder. Most previous attempts to define the heterogeneity of the condition have used prospective methods based on arbitrary features such as motor symptoms or age of disease onset. However, nonmotor symptoms including neuropsychological, neuropsychiatric, and behavioral impairments have received less attention. Sleep disturbances are extremely common in PD and appear to be associated with cognitive and psychiatric problems. Recent research has begun to elucidate the links between these variables, but the origin and extent of these relationships are not clearly understood. This review outlines the importance of sleep for healthy cognition and mood, highlighting the possible implications that disturbed sleep may have with regard to patients with PD. It also emphasizes the need for further studies that explore the heterogeneity of all disease features in PD.

Parkinson's disease and suicide: a profile of suicide victims with Parkinson's disease in a population-based study during the years 1988-2002 in Northern Finland

OBJECTIVE

We studied the prevalence of hospital-treated Parkinson's disease (PD) among suicide victims and the profile of these persons, taking into account suicide attempts, timing of depression and comorbid somatic diseases.

METHODS

The database of this study consisted of suicide victims aged 50 years of age or older (n = 555) during a fourteen-year period in the province of Oulu in Northern Finland.

RESULTS

Hospital-treated Parkinson's disease occurred in 1.6% of the subjects, indicating a rather low prevalence of suicide in this group of patients. The persons with PD had attempted suicide earlier in 44% of the cases, while the corresponding percentage for other victims in older age was 9.9% (p = 0.009 Fischer exact test).

CONCLUSIONS

Based on the case characteristics of our study the profile of PD person who completed suicide was as follows: male subject with recently diagnosed disease, living in rural area, having multiple physical illnesses, and having attempted suicide earlier. Psychiatric consultation is thus highly recommended for the PD patients with this disease profile.

The effect of onset age on the clinical features of Parkinson's disease

Many clinicians view age at onset as an important determinant of clinical phenotype in Parkinson's disease (PD) and this has been reinforced by the identification of Mendelian genes that account for some cases of younger onset PD. A systematic review of OVID Medline for articles relevant to the relationship between clinical features and age at onset in PD published in English between 1950-2007 was performed. There are very few prospective community based studies which focus on the relationship between age at onset and the features of PD and a variety of case definitions are used in the literature. Most studies of young onset PD are based on specialist clinic referral series. The available evidence suggests that PD patients with a younger age at onset have: (i) a slower disease progression, (ii) an increased rate of dystonia at onset and during treatment, (iii) a lower rate of dementia and (iv) an increased rate of dyskinesias in response to L-DOPA treatment. The majority of the available studies do not report patient genotype data, but it is probably that the clinical heterogeneity of PD will be further refined with detailed clinico-genetic studies.

Prognostic factors for the progression of Parkinson's disease: a systematic review

The purpose of this systematic review is to summarize studies that describe the course of Parkinson's disease (PD) and to identify factors that predict change in motor impairment, disability, and quality of life. A literature search was conducted in MEDLINE, EMBASE, CINAHL, and Web of Science limited to the English, French, German, Spanish, and Dutch language. Reports were selected if the study involved subjects with PD, the outcome measures described impairment, disability, or quality of life and follow-up was at least 6 months. All included studies were scored for methodological quality. Data were extracted and summarized in a best evidence synthesis. We screened 1,535 titles and abstracts, of which 27 fulfilled our inclusion criteria. A meta-analysis to quantitatively aggregate progression scores of motor impairment and disability was not possible because of the wide variety of outcome measures used and the heterogeneous study populations. Limited evidence is found for lower UPDRS-ME at baseline, dementia and SE < 70% as prognostic factors for future motor impairment. There is strong evidence for higher age at onset and higher PIGD-score; and limited evidence for higher bradykinesia-score, non-tremor dominant subtype, symmetrical disease at baseline, and depression as prognostic factors for progression of disability. Prognostic factors were identified for impairment and disability. The literature on prognosis in PD is not fulfilling the high methodological standards applied nowadays. There is a need for prospective cohorts of PD patients assembled at a common early point in the disease with long time follow-up.

Estimated life expectancy of Parkinson's patients compared with the UK population

OBJECTIVE

To calculate the best possible estimates for age specific life expectancy (LE) and anticipated age at the time of death (AAD) in patients with Parkinson's disease (PD) compared with the general population in the UK. These may be of greater value to patients than standardised mortality ratios (SMRs), which are usually reported in studies on mortality in PD.

METHODS

A literature review identified articles with data on age stratified life expectancy or SMRs to calculate estimations of LE using the Gompertz function and data on mortality and LE in the UK from the Office of National Statistics and Actuarial Department for the year 2003.

RESULTS

Two UK studies and four from Western Europe were used to estimate LE and AAD for patients with PD from SMRs. The mean LEs of patients with PD compared with the general population were: 38 (SD 5) years for onset between 25 and 39 years compared with 49 (SD 5) years; 21 (SD 5) years for onset between 40 and 64 years compared with 31 (SD 7) years; and 5 (SD 4) years for onset age > or = 65 years compared with 9 (SD 5) years. The average AAD of patients with PD with onset between 25 and 39 years was 71 (SD 3) years and considerably lower than that of the general population (82 (SD 2) years). The difference between average AAD for older individuals with PD (onset > or = 65 years) and the general population was smaller, with an AAD of approximately 88 (SD 7) years compared with 91 (SD 5) years.

CONCLUSIONS

The calculations showed that LE and AAD in PD are reduced for all onset ages but this reduction is greatest in individuals with a young onset. While the results are average estimates, these can provide useful indications of LE and AAD.

Relation between subtype of Parkinson’s disease and REM sleep behavior disorder

OBJECTIVES

Rapid eye movement (REM) sleep behavior disorder (RBD) is frequently found in Parkinson's disease (PD). PD has been classified in different subtypes and it is unknown if RBD occurs more often in one particular subtype.

METHODS

Determination of PD subtype by review of clinical history in consecutively diagnosed PD patients with RBD.

RESULTS

We determined the subtype (tremor- or non-tremor-predominant) of PD and the age at onset of parkinsonism and RBD by review of clinical history. PD patients with RBD had mostly the non-tremor-predominant subtype. RBD preceded parkinsonism only when parkinsonism started after the age of 50 years.

CONCLUSIONS

A different pattern of neurodegeneration in non-tremor-predominant PD may explain its preferential association with RBD. The neurodegeneration that causes PD might be insufficient to produce RBD before the sixth decade.

Rate of clinical progression in Parkinson's disease. A prospective study

Few prospective data on the clinical progression of Parkinson's disease (PD) in patient groups outside treatment trials in selected patients are available, and controversy exists on the rate of clinical disease progression with advancing disease. In this study, we investigated the rate of clinical progression of PD in a clinic-based sample of 145 patients over 1 year and in a community-based sample of 124 patients over 4 years. Depending on the sample and clinical scale used, mean deterioration of motor and disability scores ranged from 2.4 to 7.4% of the maximum possible score per year, and standard deviations indicated that there was considerable variability of progression rates between individuals. The progression of motor scores decreased with follow-up over 4 years and significantly decreased in more advanced disease stages. Deterioration of disability scores did not differ between disease stages; this may reflect the increasing rate of disease complications, which contribute to increasing disability in addition to motor impairment alone, in more advanced disease. Thus, motor fluctuations, hallucinations, depression, memory problems, and bladder symptoms were all reported more often at follow-up in the community-based sample (all P < 0.01), and dyskinesias, motor fluctuations, falls, and hallucinations were more common and cognitive and depression scores worse in higher disease stages in the clinic-based sample (all P < 0.001). We conclude that progression of motor scores in PD decreases with advancing disease in PD. However, disability continues to deteriorate with advancing disease and with the development of disease complications that are likely to be related to additional extrastriatal pathology.