Importance

Adherence to Mediterranean-type diet (MeDi) may delay onset of Alzheimer and Parkinson diseases. Whether adherence to MeDi affects time to phenoconversion in Huntington disease (HD), a highly penetrant, single-gene disorder, is unknown.

Objectives

To determine if MeDi modifies the time to clinical onset of HD (phenoconversion) in premanifest carriers participating in Prospective Huntington at Risk Observational Study (PHAROS), and to examine the effects of body mass index and caloric intake on time to phenoconversion.

Design, setting, and participants

A prospective cohort study of 41 Huntington study group sites in the United States and Canada involving 1001 participants enrolled in PHAROS between July 1999 and January 2004 who were followed up every 9 months until 2010. A total of 211 participants aged 26 to 57 years had an expanded CAG repeat length (≥ 37).

Exposure

A semiquantitative food frequency questionnaire was administered 33 months after baseline. We calculated daily gram intake for dairy, meat, fruit, vegetables, legumes, cereals, fish, monounsaturated and saturated fatty acids, and alcohol and constructed MeDi scores (0-9); higher scores indicate higher adherence. Demographics, medical history, body mass index, and Unified Huntington's Disease Rating Scale (UHDRS) score were collected.

Main outcome and measure

Cox proportional hazards regression models to determine the association of MeDi and phenoconversion. RESULTS Age, sex, caloric intake, education status, and UHDRS motor scores did not differ among MeDi tertiles (0-3, 4-5, and 6-9). The highest body mass index was associated with the lowest adherence to MeDi. Thirty-one participants phenoconverted. In a model adjusted for age, CAG repeat length, and caloric intake, MeDi was not associated with phenoconversion (P for trend = 0.14 for tertile of MeDi, and P = .22 for continuous MeDi). When individual components of MeDi were analyzed, higher dairy consumption (hazard ratio, 2.36; 95% CI, 1.0-5.57; P = .05) and higher caloric intake (P = .04) were associated with risk of phenoconversion.

Conclusions and relevance

MeDi was not associated with phenoconversion; however, higher consumption of dairy products had a 2-fold increased risk and may be a surrogate for lower urate levels (associated with faster progression in manifest HD). Studies of diet and energy expenditure in premanifest HD may provide data for interventions to modify specific components of diet that may delay the onset of HD.

Background

The aim of this work was to identify early clinical predictors of important outcomes in Parkinson's disease (PD). In PD, treatment-resistant (e.g., dementia, falling) and other important functional outcomes (e.g., declines in quality of life [QOL] and activities of daily living [ADL]) emerge and become increasingly disabling.

Methods

We analyzed longitudinal data from 491 early, untreated PD subjects who enrolled in the PreCEPT trial, had baseline SPECT dopamine transporter deficit, and have continued in the PostCEPT observational cohort. After PreCEPT, antiparkinsonian medications were added if needed. Baseline clinical precursors were examined as potential predictors of selected outcomes. Separate and multivariate logistic regressions, adjusted for certain baseline factors, were performed for dichotomized outcomes evaluated at the last PostCEPT visit.

Results

On enrollment, subjects had average disease duration of 0.8 years and were followed for an average of 5.5 years. Some baseline precursors were found to be predictive: disease stage, cognitive, and ADL scores for dementia; disease stage, ADL, and motor and freezing scores for hallucinations; disease stage, depression, ADL, and freezing and walking scores for falling; and ADL, depression, and motor and walking scores and disease stage for QOL decline. No baseline clinical feature predicted decline in ADL. Being on levodopa was not a significant predictor of any outcome, but subjects on a dopamine agonist were significantly less impaired with respect to falling, abnormal Mini-Mental State Examination, and QOL.

Conclusions

Although there are limitations, results support the value of longitudinal follow-up of clinical trial populations to identify early clinical precursors of important outcomes and thereby identify high-risk patients early on.

Objective

Higher serum urate concentrations predict more favorable prognosis in individuals with Parkinson disease (PD). The purpose of this study was to test the causality of this association using a Mendelian randomization approach.

Methods

The study was conducted among participants in DATATOP and PRECEPT, 2 randomized trials among patients with early PD. The 808 patients with available DNA were genotyped for 3 SLC2A9 single nucleotide polymorphisms (SNPs) that identify an allele associated with lower urate concentrations, and for selected SNPs in other genes encoding urate transporters that have modest or no effect on serum urate levels. An SLC2A9 score was created based on the total number of minor alleles at the 3 SLC2A9 loci. Primary outcome was disability requiring dopaminergic treatment.

Results

Serum urate concentrations were 0.69mg/dl lower among individuals with ≥4 SLC2A9 minor alleles as compared to those with ≤2 (p = 0.0002). The hazard ratio (HR) for progression to disability requiring dopaminergic treatment increased with increasing SLC2A9 score (HR = 1.16, 95% confidence interval [CI] = 1.00-1.35, p = 0.056). In a comparative analysis, the HR was 1.27 (95% CI = 1.00-1.61, p = 0.0497) for a 0.5mg/dl genetically conferred decrease in serum urate, and 1.05 (95% CI = 1.01-1.10, p = 0.0133) for a 0.5mg/dl decrease in measured serum urate. No associations were found between polymorphisms in other genes associated with urate that do not affect serum urate and PD progression.

Interpretation

This Mendelian randomization analysis adds to the evidence of a causal protective effect of high urate levels.

BACKGROUND:In Huntington's disease, 60% of the variance in onset age is not explained by the huntingtin gene mutation. Huntington's disease onset was earlier in caffeine users. OBJECTIVE:The objective of this study was to assess the relationship of lifestyle factors with motor phenoconversion among persons at risk for Huntington's disease. METHODS:The associations of motor phenoconversion and exposure to selected lifestyle and health factors were examined using Cox proportional hazards analyses adjusted for age, gender, and repeat length. RESULTS:Of 247 participants, 36 (14.6%) phenoconverted. Mean follow-up was 4.2 years. Greater caffeinated soda use was associated with an increased hazard of phenoconversion: moderate use hazard ratio 2.26 (95% confidence interval 0.59-8.71), high use hazard ratio 4.05 (95% confidence interval 1.18-13.96). CONCLUSIONS:Huntington's disease onset was earlier among consumers of caffeinated soda, but not other caffeinated beverages. This finding may be spurious or not related to caffeine. © 2018 International Parkinson and Movement Disorder Society.

BACKGROUND: Free-text, verbatim replies in the words of people with Parkinsons disease (PD) have the potential to provide unvarnished information about their feelings and experiences. Challenges of processing such data on a large scale are a barrier to analyzing verbatim data collection in large cohorts. OBJECTIVE: To develop a method for curating responses from the Parkinsons Disease Patient Report of Problems (PD-PROP), open-ended questions that asks people with PD to report their most bothersome problems and associated functional consequences. METHODS: Human curation, natural language processing, and machine learning were used to develop an algorithm to convert verbatim responses to classified symptoms. Nine curators including clinicians, people with PD, and a non-clinician PD expert classified a sample of responses as reporting each symptom or not. Responses to the PD-PROP were collected within the Fox Insight cohort study. RESULTS: Approximately 3,500 PD-PROP responses were curated by a human team. Subsequently, approximately 1,500 responses were used in the validation phase; median age of respondents was 67 years, 55% were men and median years since PD diagnosis was 3 years. 168,260 verbatim responses were classified by machine. Accuracy of machine classification was 95% on a held-out test set. 65 symptoms were grouped into 14 domains. The most frequently reported symptoms at first report were tremor (by 46% of respondents), gait and balance problems (>39%), and pain/discomfort (33%). CONCLUSION: A human-in-the-loop method of curation provides both accuracy and efficiency, permitting a clinically useful analysis of large datasets of verbatim reports about the problems that bother PD patients.

Background

There are few established predictors of the clinical course of PD. Prognostic markers would be useful for clinical care and research.

Objective

To identify predictors of long-term motor and cognitive outcomes and rate of progression in PD.

Methods

Newly diagnosed PD participants were followed for 7 years in a prospective study, conducted at 55 centers in the United States and Canada. Analyses were conducted in 244 participants with complete demographic, clinical, genetic, and dopamine transporter imaging data. Machine learning dynamic Bayesian graphical models were used to identify and simulate predictors and outcomes. The outcomes rate of cognition changes are assessed by the Montreal Cognitive Assessment scores, and rate of motor changes are assessed by UPDRS part-III.

Results

The most robust and consistent longitudinal predictors of cognitive function included older age, baseline Unified Parkinson's Disease Rating Scale (UPDRS) parts I and II, Schwab and England activities of daily living scale, striatal dopamine transporter binding, and SNP rs11724635 in the gene BST1. The most consistent predictor of UPDRS part III was baseline level of activities of daily living (part II). Key findings were replicated using long-term data from an independent cohort study.

Conclusions

Baseline function near the time of Parkinson's disease diagnosis, as measured by activities of daily living, is a consistent predictor of long-term motor and cognitive outcomes. Additional predictors identified may further characterize the expected course of Parkinson's disease and suggest mechanisms underlying disease progression. The prognostic model developed in this study can be used to simulate the effects of the prognostic variables on motor and cognitive outcomes, and can be replicated and refined with data from independent longitudinal studies.

Dopamine (DA) transporter (DAT) imaging has been studied as a diagnostic tool for degenerative parkinsonism. Our aim was to measure the prognostic value of imaging for motor and nonmotor outcomes in Parkinson's disease (PD). We prospectively evaluated a Parkinson's cohort after enrollment in a de novo clinical trial with a battery of motor (UPDRS), cognitive (Montreal Cognitive Assessment), and behavioral measures. DAT imaging with [(123)I][β]-CIT and single-photon emission computerized tomography (SPECT) was performed at baseline and after 22 months. In total, 491 (91%) of the 537 subjects had evidence of DA deficiency on their baseline scan, consistent with PD, and were included in the analyses. The cohort was followed for 5.5 (0.8) years, with a mean duration of diagnosis of 6.3 (1.2). Lower striatal binding at baseline was independently associated with higher risk for clinical milestones and measures of disease severity, including motor-related disability, falling and postural instability, cognitive impairment, psychosis, and clinically important depressive symptoms. Subjects in the bottom quartile for striatal binding, compared to the top quartile, had an odds ratio (95% confidence interval) of 3.3 (1.7, 6.7) for cognitive impairment and 12.9 (2.6, 62.4) for psychosis. Change from baseline in imaging after 22 months was also independently associated with motor, cognitive, and behavioral outcomes. DAT imaging with [(123)I][β]-CIT and SPECT, shortly after the diagnosis of PD, was independently associated with clinically important long-term motor and nonmotor outcomes. These results should be treated as hypothesis generating and require confirmation.

The objective of this study was to examine a remote method for maintaining long-term contact with Parkinson's disease (PD) patients participating in clinical studies. Long-term follow-up of PD patients is needed to fill critical information gaps on progression, biomarkers, and treatment. Prospective in-person assessment can be costly and may be impossible for some patients. Remote assessment using mail and telephone contact may be a practical follow-up method. Patients enrolled in the multi-center Longitudinal and Biomarker Study in Parkinson's Disease (LABS-PD) in-person follow-up study in 2006 were invited to enroll in Follow-up of Persons With Neurologic Diseases (FOUND), which is overseen by a single center under a separate, central institutional review board protocol. FOUND uses mailed questionnaires and telephone interviews to assess PD status. FOUND follow-up continued when LABS-PD in-person visits ended in 2011. Retention and agreement between remote and in-person assessments were determined. In total, 422 of 499 (84.5%) of eligible patients volunteered, AND 96% of participants were retained. Of 60 patients who withdrew consent from LABS-PD, 51 were retained in FOUND. Of 341 patients who were active in LABS-PD, 340 were retained in FOUND (99.7%) when the in-person visits ceased. Exact agreement between remote and in-person assessments was ≥ 80% for diagnosis, disease features (eg, dyskinesias), and PD medication. Correlation between expert-rated and self-reported Unified Parkinson's Disease Rating Scale and Movement Disorder Society Unified Parkinson's Disease Rating Scale, which were examined at times separated by several months, was moderate or substantial for most items. Retention was excellent using remote follow-up of research participants with PD, providing a safety net when combined with in-person visits, and also is effective as a stand-alone assessment method, providing a useful alternative when in-person evaluation is not feasible.

Background

Clinical research in Parkinson's disease (PD) faces practical and ethical challenges due to two interrelated problems: participant under-recruitment and lack of diversity. Fox Insight (FI) is a web-based longitudinal study collecting patient-reported outcomes and genetic data worldwide to inform therapeutic studies. FI's online platform provides an opportunity to evaluate online strategies for recruiting large, diverse research cohorts.

Objective

This project aimed to determine 1) whether FI's digital marketing was associated with increased enrollment overall and from under-represented patient groups, compared to traditional recruitment methods; 2) the clinical and demographic characteristics of samples recruited online, and 3) the cost of this online recruitment.

Method

FI recruitment during a 6-week baseline period without digital promotion was compared to recruitment during several periods of digital outreach. Separate online recruiting intervals included general online study promotion and unique Facebook and Google ad campaigns targeting under-represented subgroups: early PD, late/advanced PD, and residents of underrepresented/rural geographic areas.

Results

Early PD, late PD, and geotargeting campaigns enrolled more individuals in their respective cohorts compared to baseline. All online campaigns also yielded greater total FI enrollment, attracting more participants who were non-White, Hispanic, older, female, and had lower educational attainment and income, and more medical comorbidities. Cost per new participant ranged from $21 (Facebook) to $108 (Google).

Conclusion

Digital marketing may allow researchers to increase, accelerate, and diversify recruitment for PD clinical studies, by tailoring digital ads to target PD cohort characteristics.

Background

Online tools for data collection could be of value in patient-oriented research. The Fox Insight (FI) study collects data online from individuals with self-reported Parkinson's disease (PD). Comparing the FI cohort to other cohorts assessed through more traditional (in-person) observational research studies would inform the representativeness and utility of FI data.

Objective

To compare self-reported demographic characteristics, symptoms, medical history, and PD medication use of the FI PD cohort to other recent observational research study cohorts assessed with in-person visits.

Methods

The FI PD cohort (n = 12,654) was compared to 3 other cohorts, selected based on data accessibility and breadth of assessments: Parkinson's Progression Markers Initiative (PPMI; PD n = 422), Parkinson's Disease Biomarker Program (PDBP; n = 700), and PD participants in the LRRK2 consortium without LRRK2 mutations (n = 508). Demographics, motor and non-motor assessments, and medications were compared across cohorts. Where available, identical items on surveys and assessments were compared; otherwise, expert opinion was used to determine comparable definitions for a given variable.

Results

The proportion of females was significantly higher in FI (45.56%) compared to PPMI (34.36%) and PDBP (35.71%). The FI cohort had greater educational attainment as compared to all other cohorts. Overall, prevalence of difficulties with motor experiences of daily living and non-motor symptoms in the FI cohort was similar to other cohorts, with only a few significant differences that were generally small in magnitude. Missing data were rare for the FI cohort, except on a few variables.

Discussion

Patterns of responses to patient-reported assessments obtained online on the PD cohort of the FI study were similar to PD cohorts assessed in-person.