The impact of motor symptoms on self-reported anxiety in Parkinson's disease

OBJECTIVE: Anxiety is commonly endorsed in Parkinson's disease (PD) and significantly affects quality of life. The Beck Anxiety Inventory (BAI) is often used but contains items that overlap with common PD motor symptoms (e.g., “hands trembling”). Because of these overlapping items, we hypothesized that PD motor symptoms would significantly affect BAI scores. METHODS: One hundred non-demented individuals with PD and 74 healthy control participants completed the BAI. PD motor symptoms were assessed by the Unified Parkinson's Disease Rating Scale (UPDRS). Factor analysis of the BAI assessed for a PD motor factor, and further analyses assessed how this factor affected BAI scores. RESULTS: BAI scores were significantly higher for PD than NC. A five-item PD motor factor correlated with UPDRS observer-rated motor severity and mediated the PD-control difference on BAI total scores. An interaction occurred, whereby removal of the PD motor factor resulted in a significant reduction in BAI scores for PD relative to NC. The correlation between the BAI and UPDRS significantly declined when controlling for the PD motor factor. CONCLUSIONS: The results indicate that commonly endorsed BAI items may reflect motor symptoms such as tremor instead of, or in addition to, genuine mood symptoms. These findings highlight the importance of considering motor symptoms in the assessment of anxiety in PD and point to the need for selecting anxiety measures that are less subject to contamination by the motor effects of movement disorders.Published versio

Bistable perception in normal aging: perceptual reversibility and its relation to cognition

The effects of age on the ability to resolve perceptual ambiguity are unknown, though it depends on fronto-parietal attentional networks known to change with age. We presented the bistable Necker cube to 24 middle-aged and older adults (OA; 56–78 years) and 20 younger adults (YA; 18–24 years) under passive-viewing and volitional control conditions: Hold one cube percept and Switch between cube percepts. During passive viewing, OA had longer dominance durations (time spent on each percept) than YA. In the Hold condition, OA were less able than YA to increase dominance durations. In the Switch condition, OA and YA did not differ in performance. Dominance durations in either condition correlated with performance on tests of executive function mediated by the frontal lobes. Eye movements (fixation deviations) did not differ between groups. These results suggest that OA’s reduced ability to hold a percept may arise from reduced selective attention. The lack of correlation of performance between Hold and executive-function measures suggests at least a partial segregation of underlying mechanisms.Published versionAccepted manuscrip

Web-based Assessment of Visual and Visuospatial Symptoms in Parkinson\u27s Disease

Visual and visuospatial dysfunction is prevalent in Parkinson’s disease (PD). To promote assessment of these often overlooked symptoms, we adapted the PD Vision Questionnaire for Internet administration. The questionnaire evaluates visual and visuospatial symptoms, impairments in activities of daily living (ADLs), and motor symptoms. PD participants of mild to moderate motor severity (n = 24) and healthy control participants (HC, n = 23) completed the questionnaire in paper and web-based formats. Reliability was assessed by comparing responses across formats. Construct validity was evaluated by reference to performance on measures of vision, visuospatial cognition, ADLs, and motor symptoms. The web-based format showed excellent reliability with respect to the paper format for both groups (all P_s \u3c 0.001; HC completing the visual and visuospatial section only). Demonstrating the construct validity of the web-based questionnaire, self-rated ADL and visual and visuospatial functioning were significantly associated with performance on objective measures of these abilities (all P_s \u3c 0.01). The findings indicate that web-based administration may be a reliable and valid method of assessing visual and visuospatial and ADL functioning in PD

Web-Based Assessment of Visual and Visuospatial Symptoms in Parkinson's Disease

Visual and visuospatial dysfunction is prevalent in Parkinson's disease (PD). To promote assessment of these often overlooked symptoms, we adapted the PD Vision Questionnaire for Internet administration. The questionnaire evaluates visual and visuospatial symptoms, impairments in activities of daily living (ADLs), and motor symptoms. PD participants of mild to moderate motor severity (n = 24) and healthy control participants (HC, n = 23) completed the questionnaire in paper and web-based formats. Reliability was assessed by comparing responses across formats. Construct validity was evaluated by reference to performance on measures of vision, visuospatial cognition, ADLs, and motor symptoms. The web-based format showed excellent reliability with respect to the paper format for both groups (all P′s < 0.001; HC completing the visual and visuospatial section only). Demonstrating the construct validity of the web-based questionnaire, self-rated ADL and visual and visuospatial functioning were significantly associated with performance on objective measures of these abilities (all P′s < 0.01). The findings indicate that web-based administration may be a reliable and valid method of assessing visual and visuospatial and ADL functioning in PD

Relation of Parkinson\u27s Disease Subtypes to Visual Activities of Daily Living

Visual perceptual problems are common in Parkinson\u27s disease (PD) and often affect activities of daily living (ADLs). PD patients with non-tremor symptoms at disease onset (i.e., rigidity, bradykinesia, gait disturbance or postural instability) have more diffuse neurobiological abnormalities and report worse non-motor symptoms and functional changes than patients whose initial symptom is tremor, but the relation of motor symptom subtype to perceptual deficits remains unstudied. We assessed visual ADLs with the Visual Activities Questionnaire in 25 non-demented patients with PD, 13 with tremor as the initial symptom and 12 with an initial symptom other than tremor, as well as in 23 healthy control participants (NC). As expected, the non-tremor patients, but not the tremor patients, reported more impairment in visual ADLs than the NC group, including in light/dark adaptation, acuity/spatial vision, depth perception, peripheral vision and visual processing speed. Non-tremor patients were significantly worse than tremor patients overall and on light/dark adaptation and depth perception. Environmental enhancements especially targeted to patients with the non-tremor PD subtype may help to ameliorate their functional disability