Reading Difficulties in Parkinson's Disease: A Stepped Care Model for Neurovisual Rehabilitation.

BACKGROUND: People with Parkinson's disease (PD) frequently experience reading difficulties. Little is known about what functional impairments distinguish people with PD with and without reading difficulties and how these should guide rehabilitation. OBJECTIVE: To provide concrete advice for an efficient stepped care model for reading difficulties in PD, based on extensive functional assessments. METHODS: This study included 74 people with PD in a neurovisual rehabilitation setting who underwent assessment of visual, visuoperceptual, and cognitive functions. Outcomes were compared between those with frequent (RD+; N = 55) and infrequent reading difficulties (RD-; N = 19). Aids and advice provided during rehabilitation were registered. RESULTS: Only a few functions appeared to distinguish RD+ and RD-. Visual functions (i.e., contrast sensitivity, g = 0.76; reading acuity, g = 0.66; visual acuity, g = 0.54) and visuoperceptual functions (i.e., visual attention, g = 0.58, visual motor speed, g = 0.56) showed significant worse scores in RD+ compared to RD-. Aids and advice applied consisted mainly of optimizing refraction, improving lighting, and optimizing text size and spacing. CONCLUSION: The test battery showed significant differences between RD+ and RD-on only a few tests on visual and visuoperceptual functions. The applied aids and advice matched well with these impairments. Therefore, we recommend a stepped care model, starting with a short test battery on these functions. If this battery indicates functional impairments, this can be followed by standard aids and advice to improve reading. Only in case of insufficient effect additional testing should take place.

Prevalence and nature of self-reported visual complaints in people with Parkinson's disease-Outcome of the Screening Visual Complaints questionnaire.

INTRODUCTION: Visual complaints can have a vast impact on the quality of life of people with Parkinson's disease (PD). In clinical practice however, visual complaints often remain undetected. A better understanding of visual complaints is necessary to optimize care for people with PD and visual complaints. This study aims at determining the prevalence of visual complaints experienced by a large outpatient cohort of people with PD compared to a control group. In addition, relations between visual complaints and demographic and disease-related variables are investigated. METHODS: The Screening Visual Complaints questionnaire (SVCq) screened for 19 visual complaints in a cohort of people with idiopathic PD (n = 581) and an age-matched control group without PD (n = 583). RESULTS: People with PD experienced significantly more complaints than controls, and a greater impact of visual complaints on their daily lives. Complaints that were most common ('often/always') were unclear vision (21.7%), difficulty reading (21.6%), trouble focusing (17.1%), and blinded by bright light (16.8%). Largest differences with controls were found for double vision, needing more time to see and having trouble with traffic participation due to visual complaints. Age, disease duration, disease severity, and the amount of antiparkinsonian medication related positively to the prevalence and severity of visual complaints. CONCLUSION: Visual complaints are highly prevalent and occur in great variety in people with PD. These complaints progress with the disease and have a large impact on the daily lives of these people. Standardized questioning is advised for timely recognition and treatment of these complaints.

Correction: The Screening Visual Complaints questionnaire (SVCq) in people with Parkinson's disease-Confirmatory factor analysis and advice for its use in clinical practice.

[This corrects the article DOI: 10.1371/journal.pone.0272559.].

The Screening Visual Complaints questionnaire (SVCq) in people with Parkinson's disease-Confirmatory factor analysis and advice for its use in clinical practice.

BACKGROUND: The Screening Visual Complaints questionnaire (SVCq) is a short questionnaire to screen for visual complaints in people with Parkinson's disease (PD). OBJECTIVE: The current study aims to investigate the factor structure of the SVCq to increase the usability of this measure in clinical practice and facilitate the interpretation of visual complaints in people with PD. METHODS: We performed a confirmatory factor analysis using the 19 items of the SVCq of 581 people with PD, investigating the fit of three models previously found in a community sample: a one-factor model including all items, and models where items are distributed across either three or five factors. The clinical value of derived subscales was explored by comparing scores with age-matched controls (N = 583), and by investigating relationships to demographic and disease related characteristics. RESULTS: All three models showed a good fit in people with PD, with the five-factor model outperforming the three-factor and one-factor model. Five factors were distinguished: 'Diminished visual perception-Function related' (5 items), 'Diminished visual perception-Luminance related' (3 items), 'Diminished visual perception-Task related' (3 items), 'Altered visual perception' (6 items), and 'Ocular discomfort' (2 items). On each subscale, people with PD reported more complaints than controls, even when there was no ophthalmological condition present. Furthermore, subscales were sensitive to relevant clinical characteristics, like age, disease duration, severity, and medication use. CONCLUSIONS: The five-factor model showed a good fit in people with PD and has clinical relevance. Each subscale provides a solid basis for individualized visual care.

Confirmatory factor analysis of the Dutch Screening Visual Complaints questionnaire in people with multiple sclerosis.

BACKGROUND: Visual complaints among people with multiple sclerosis (pwMS) are common, but often difficult to recognize. The Screening Visual Complaints questionnaire (SVCq) has been developed to screen for visual complaints in people with a neurodegenerative disease, including multiple sclerosis (MS). A previous study performed a factor analysis in a normal population which revealed an acceptable one-factor model, a three-factor model and a five-factor model within the SVCq. To increase the usability of the SVCq in people with MS, the purpose of the current study was to investigate the fit of the three models in a cohort of pwMS. RESULTS: The confirmatory factor analysis on the SVCq in 493 people with MS showed good fit for all the models. The three-factor model (diminished visual perception, altered visual perception and ocular discomfort) outperformed the one-factor model. The five-factor model outperformed both models, which showed that dividing the first factor (diminished visual perception) into three more factors (function-related, luminance-related and task-related) has merit. CONCLUSIONS: All models may be useful in clinical care for pwMS. The one-factor model may give a quick overview of the presence and severity of visual complaints in general. The individual factors, of either the three- or the five factor models, may contribute to a better recognition of the nature of visual complaints in pwMS and may guide further steps in rehabilitation for pwMS with visual complaints.

Self-Reported Visual Complaints in People with Parkinson's Disease: A Systematic Review.

BACKGROUND: Scientific research increasingly focuses on visual symptoms of people with Parkinson's disease (PD). However, this mostly involves functional measures, whereas self-reported data are equally important for guiding clinical care. OBJECTIVE: This review provides an overview of the nature and prevalence of self-reported visual complaints by people with PD, compared to healthy controls. METHODS: A systematic literature search was performed. Studies from three databases (PubMed, PsycInfo, and Web of Science) were screened for eligibility. Only studies that reported results of visual self-reports in people with idiopathic PD were included. RESULTS: One hundred and thirty-nine eligible articles were analyzed. Visual complaints ranged from function-related complaints (e.g., blurred vision, double vision, increased sensitivity to light or changes in contrast sensitivity) to activity-related complaints (e.g., difficulty reading, reaching, or driving). Visual complaints were more prevalent in people with PD compared to healthy controls. The presence of visual complaints leads to a reduced quality of life (QoL). Increased prevalence and severity of visual complaints in people with PD are related to longer disease duration, higher disease severity, and off-state. CONCLUSION: A large proportion of people with PD have visual complaints, which negatively affect QoL. Complaints are diverse in nature, and specific and active questioning by clinicians is advised to foster timely recognition, acknowledgement, and management of these complaints.

The development of the Screening of Visual Complaints questionnaire for patients with neurodegenerative disorders: Evaluation of psychometric features in a community sample.

BACKGROUND AND OBJECTIVES: Patients with neurodegenerative disorders often experience impairments in visual function. In research and clinical care, visual problems are primarily understood as objective visual impairments. Subjective complaints, referring to complaints from a patient's perspective, receive less attention, while they are of utmost clinical importance to guide assessment and rehabilitation. A 21-item Screening of Visual Complaints questionnaire (SVC) was developed for the assessment of subjective visual complaints in patients with neurodegenerative disorders. This prospective study aims to evaluate the psychometric properties of the SVC in a large community sample. METHODS: A stratified convenience sample of 1,461 healthy Dutch participants (18-95 years) without severe self-reported neurological, ophthalmological or psychiatric conditions completed the SVC, Cerebral Visual Complaints questionnaire (CVC-q), National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25), Behavior Rating Inventory of Executive Function-A (BRIEF-A), Questionnaire for Experiences of Attention Deficits (Fragebogen erlebter Defizite der Aufmerkzamkeit; FEDA), Depression Anxiety Stress Scale-21 (DASS-21) and the Structured Inventory for Malingered Symptomatology (SIMS) online. After two weeks, 66 participants completed the SVC again. We evaluated the factor structure, internal consistency, convergent and divergent validity, and test-retest reliability of the SVC. RESULTS: The sample was split in two subsamples to perform exploratory and confirmatory factor analyses. In the first subsample, the exploratory factor analysis extracted three factors from the SVC: diminished visual perception, altered visual perception and ocular discomfort. The confirmatory factor analysis showed this model to be valid in the second subsample. The SVC showed satisfactory convergent validity (NEI-VFQ-25: r = -0.71; CVC-q: r = 0.84) and divergent validity (SIMS: r = 0.26; BRIEF-A: r = 0.29; FEDA: r = 0.40; DASS-21: r = 0.34) and good internal consistency (Cronbach's alpha = 0.85) and test-retest reliability (ICC = 0.82). CONCLUSIONS: The SVC is a valid and reliable tool for the assessment of subjective visual complaints in a community sample and appears promising for clinical use in patients with neurodegenerative disorders.