Belén Frades-Payo

The Nondeclaration of Nonmotor Symptoms of Parkinson's Disease to Health Care Professionals: An International Study Using the Nonmotor Symptoms Questionnaire

The nonmotor symptoms (NMS) of Parkinsons disease (PD) are less well recognised and can be more troublesome to patients and carers than classical motor features. NMS are frequently missed during routine consultations and such under‐recognition may have implications on quality of care given that many NMS are treatable. To determine the proportion of patients not declaring NMS to healthcare professional (HCP) as assessed by self completion of the NMS questionnaire (NMSQuest), a validated, self‐completing questionnaire with 30 items. Multicentre international study. The data was collected from PD patients across all age groups and stages attending outpatient clinics in specialist and care of the elderly settings. 242 patients recruited and undeclared NMS ranged from 31.8% (diplopia) to 65.2% (delusions). The most frequently nondeclared symptoms were delusions, daytime sleepiness, intense and vivid dreams, and dizziness. In many, appropriate treatments for undeclared NMS were started only after these were recognised following completion of NMSQuest. NMS of PD are frequently undeclared at routine hospital consultation and may be related to the fact that patients often do not link these symptoms with PD or may be too embarrassed to discuss these. Use of NMSQuest allows patients to flag symptoms which may be otherwise undeclared and remain untreated when potential treatments exist.

Psychometric attributes of the Hospital Anxiety and Depression Scale in Parkinson's disease

The Hospital Anxiety and Depression Scale (HADS) has been used in Parkinsons disease (PD) but information about its psychometric properties in this context is limited. The aim of this study is to assess the psychometric properties of the HADS in PD. In an observational, cross‐sectional analysis, HADS data quality, acceptability, scaling assumptions, internal consistency, construct validity, and precision were explored. From a sample of 387 PD patients, 22% and 14% scored ≥11 points (definite case) on the HADS anxiety and depression subscales, respectively. Cronbachs alpha was 0.81 and 0.83 for these subscales. Factor analysis revealed two factors (49.8% of the variance) representing anxiety and depression. The HADS closely correlated with health‐related quality of life (HRQL) measures and displayed satisfactory discriminative validity for patients grouped by severity level, disease duration, HRQL status, and treatment. The SEM was 1.84 for HADS‐Anxiety and 1.72 for HADS‐Depression. The HADS is an acceptable, consistent, valid, precise, and potentially responsive scale for use in PD.

Independent validation of the scales for outcomes in Parkinson’s disease‐autonomic (SCOPA‐AUT)

Background and purpose:  Autonomic dysfunction is common in Parkinson’s disease (PD) and causes a great impact in health‐related quality of life (HRQL) and functional status of patients. This study is the first independent validation of the Scales for Outcomes in PD‐Autonomic (SCOPA‐AUT).

A blood-based, 7-metabolite signature for the early diagnosis of Alzheimer's disease.

Accurate blood-based biomarkers of Alzheimers disease (AD) could constitute simple, inexpensive, and non-invasive tools for the early diagnosis and treatment of this devastating neurodegenerative disease. We sought to develop a robust AD biomarker panel by identifying alterations in plasma metabolites that persist throughout the continuum of AD pathophysiology. Using a multicenter, cross-sectional study design, we based our analysis on metabolites whose levels were altered both in AD patients and in patients with amnestic mild cognitive impairment (aMCI), the earliest identifiable stage of AD. UPLC coupled to mass spectrometry was used to independently compare the levels of 495 plasma metabolites in aMCI (n = 58) and AD (n = 100) patients with those of normal cognition controls (NC, n = 93). Metabolite alterations common to both aMCI and AD patients were used to generate a logistic regression model that accurately distinguished AD from NC patients. The final panel consisted of seven metabolites: three amino acids (glutamic acid, alanine, and aspartic acid), one non-esterified fatty acid (22:6n-3, DHA), one bile acid (deoxycholic acid), one phosphatidylethanolamine [PE(36:4)], and one sphingomyelin [SM(39:1)]. Detailed analysis ruled out the influence of potential confounding variables, including comorbidities and treatments, on each of the seven biomarkers. The final model accurately distinguished AD from NC patients (AUC, 0.918). Importantly, the model also distinguished aMCI from NC patients (AUC, 0.826), indicating its potential diagnostic utility in early disease stages. These findings describe a sensitive biomarker panel that may facilitate the specific detection of early-stage AD through the analysis of plasma samples.

Assessing autonomic symptoms of Parkinson's disease with the SCOPA-AUT: a new perspective from Rasch analysis

Background:  The Scale for Outcomes in Parkinson’s disease (PD) for Autonomic Symptoms (SCOPA‐AUT) is a specific scale to assess autonomic dysfunction in PD patients. It was developed and validated under the classic test theory approach. This study sought to test whether the SCOPA‐AUT meets item response theory standards for reliability, internal construct validity, response category ordering, and differential item functioning by gender and age group.

Validation of the Functional Independence Scale

OBJECTIVE To assess the psychometric quality of an instrument designed to measure functional independence (Functional Independence Scale [FIS]) in several activities of daily living domains and to be applied by trained non-health-related interviewers. The study was carried out in the autonomous region of Madrid in community-dwelling elders. METHODS We performed a cross-sectional validation study. In addition to the FIS, Pfeiffers questionnaire, the Depression Subscale of the Hospital Anxiety and Depression Scale, the Comorbidity Index, the Barthel Index, and EQ-5D were used. These measures were cross-sectionally applied to community-dwelling elders (n=500) and outpatients in a general hospital (n=100) aged 65 years. The following FIS psychometric attributes were analyzed: acceptability, scaling assumptions, internal consistency, construct validity, and precision. RESULTS A fully computable FIS total score was obtained in 94.3% of the subjects. A ceiling effect (60.65%), but no floor effect (0.22%) was evident in the community-dwelling elders. No floor or ceiling effects were detected in the hospital sample. Scaling assumptions and internal consistency were satisfactory (item-total correlations: 0.57-0.91; Cronbachs alpha: 0.94). Factor analysis identified three factors that explained 74.3% of the variance. Indexes of convergent, internal, and known-groups validity were satisfactory. The scales precision, determined by the standard error of measurement (2.49; 95%CI=4.88), was also satisfactory. CONCLUSION The FIS is an easy-to-use instrument with appropriate metric attributes. This scale can be usefully applied in broad samples of non-institutionalized elders by non-health related personnel.

Should the SCOPA-COG be modified?: a Rasch analysis perspective

Background and purpose:  The SCales for Outcomes in PArkinson’s disease‐Cognition (SCOPA‐COG) is a specific measure of cognitive function for Parkinson’s disease (PD) patients. Previous studies, under the frame of the classic test theory, indicate satisfactory psychometric properties. The Rasch model, an item response theory approach, provides new information about the scale, as well as results in a linear scale. This study aims at analysing the SCOPA‐COG according to the Rasch model and, on the basis of results, suggesting modification to the SCOPA‐COG.

Parkinson Symptoms and Health Related Quality of Life as Predictors of Costs: A Longitudinal Observational Study with Linear Mixed Model Analysis.

Objective To estimate the magnitude in which Parkinson’s disease (PD) symptoms and health- related quality of life (HRQoL) determined PD costs over a 4-year period. Materials and Methods Data collected during 3-month, each year, for 4 years, from the ELEP study, included sociodemographic, clinical and use of resources information. Costs were calculated yearly, as mean 3-month costs/patient and updated to Spanish €, 2012. Mixed linear models were performed to analyze total, direct and indirect costs based on symptoms and HRQoL. Results One-hundred and seventy four patients were included. Mean (SD) age: 63 (11) years, mean (SD) disease duration: 8 (6) years. Ninety-three percent were HY I, II or III (mild or moderate disease). Forty-nine percent remained in the same stage during the study period. Clinical evaluation and HRQoL scales showed relatively slight changes over time, demonstrating a stable group overall. Mean (SD) PD total costs augmented 92.5%, from €2,082.17 (€2,889.86) in year 1 to €4,008.6 (€7,757.35) in year 4. Total, direct and indirect cost incremented 45.96%, 35.63%, and 69.69% for mild disease, respectively, whereas increased 166.52% for total, 55.68% for direct and 347.85% for indirect cost in patients with moderate PD. For severe patients, cost remained almost the same throughout the study. For each additional point in the SCOPA-Motor scale total costs increased €75.72 (p = 0.0174); for each additional point on SCOPA-Motor and the SCOPA-COG, direct costs incremented €49.21 (p = 0.0094) and €44.81 (p = 0.0404), respectively; and for each extra point on the pain scale, indirect costs increased €16.31 (p = 0.0228). Conclusions PD is an expensive disease in Spain. Disease progression and severity as well as motor and cognitive dysfunctions are major drivers of costs increments. Therapeutic measures aimed at controlling progression and symptoms could help contain disease expenses.

Specific patient-reported outcome measures for Parkinson's disease: analysis and applications

Patient-reported outcomes (PROs) are defined as the “patient’s report of a health condition and its treatment”. This type of assessment encompasses symptoms, functional status, psychological well-being, health-related quality of life (HRQoL) and other aspects. PROs are increasingly used in clinical practice and research, owing to the uniqueness of the data they furnish. The methodology used to design and test PRO instruments is drawn from psychology, social sciences and education. The present review focuses on PROs (since 2000) and HRQoL instruments specific to Parkinson’s disease. Parkinson’s disease is a complex disease that causes motor and nonmotor manifestations, many of which can only be assessed through PRO measures. New PRO instruments and active research to improve their scientific quality are to be expected in the next 5 years.

Propiedades psicométricas del Cuestionario de Apoyo Social Funcional y de la Escala de Soledad en adultos mayores no institucionalizados en España

OBJECTIVES To examine the psychometric properties of the Social Support Questionnaire Duke-UNC (DUFSS) and the De Jong-Gierveld Loneliness Scale in a sample of non-institutionalized older adults. METHODS The sample consisted of 1,106 non-institutionalized older adults included in a national survey on quality of life. Both scales were analyzed according to classical test theory (acceptability, internal consistency, internal validity, convergent validity, discriminant validity and accuracy) and Rasch analysis. RESULTS The mean ± standard deviation scores were 44.95 ± 8.9 for the DUFSS and 1.92 ± 1.83 for the Loneliness Scale. Cronbachs alpha was 0.94 for the DUFSS and 0.77 for the Loneliness Scale. Factor analysis identified two factors in each scale (explained variance: 73.8% for the DUFSS and 67.7% for the Loneliness Scale). The instruments showed a correlation of -0.59 with each other. Rasch analysis of the DUFSS identified two dimensions with a good model fit, whereas the Loneliness Scale did not fit the Rasch model. CONCLUSIONS The DUFSS, with some modifications, meets the Rasch assumptions and provides linear measures. However, more Rasch analysis studies are needed for the Loneliness Scale. According to classical test theory, the DUFSS has good internal consistency for comparisons among people and the Loneliness Scale for comparisons among groups. Both scales have satisfactory construct validity.