Mild cognitive impairment in Parkinson disease: a multicenter pooled analysis.

BACKGROUND: In studies of mild cognitive impairment (MCI) in Parkinson disease (PD), patients without dementia have reported variable prevalences and profiles of MCI, likely to be due to methodologic differences between the studies. OBJECTIVE: The objective of this study was to determine frequency and the profile of MCI in a large, multicenter cohort of well-defined patients with PD using a standardized analytic method and a common definition of MCI. METHODS: A total of 1,346 patients with PD from 8 different cohorts were included. Standardized analysis of verbal memory, visuospatial, and attentional/executive abilities was performed. Subjects were classified as having MCI if their age- and education-corrected z score on one or more cognitive domains was at least 1.5 standard deviations below the mean of either control subjects or normative data. RESULTS: A total of 25.8% of subjects (95% confidence interval [CI] 23.5-28.2) were classified as having MCI. Memory impairment was most common (13.3%; 11.6-15.3), followed by visuospatial (11.0%; 9.4-13.0) and attention/executive ability impairment (10.1%; 8.6-11.9). Regarding cognitive profiles, 11.3% (9.7-13.1) were classified as nonamnestic single-domain MCI, 8.9% (7.0-9.9) as amnestic single-domain, 4.8% (3.8-6.1) as amnestic multiple-domain, and 1.3% (0.9-2.1) as nonamnestic multiple-domain MCI. Having MCI was associated with older age at assessment and at disease onset, male gender, depression, more severe motor symptoms, and advanced disease stage. CONCLUSIONS: MCI is common in patients with PD without dementia, affecting a range of cognitive domains, including memory, visual-spatial, and attention/executive abilities. Future studies of patients with PD with MCI need to determine risk factors for ongoing cognitive decline and assess interventions at a predementia stage.

Swallowing problems in Parkinson disease: frequency and clinical correlates.

BACKGROUND: Changes to the efficiency and integrity of swallowing mechanisms are inevitable in Parkinson disease (PD); however, it remains unclear how many people with PD are at risk of dysphagia. The aim of this study was to establish the frequency of impaired swallowing in people with PD and the relationship between swallowing performance and indicators of disease progression. METHODS: A community-based and hospital-based cohort of 137 individuals with PD were asked to drink 150 ml of water as quickly as possible while in an 'off drug' state. RESULTS: Thirty-one (23%) patients could not completely drink the full 150 ml. Swallowing rate (ml/sec) fell to more than 1 SD below published norms for 115 (84%) patients and to more than 2SD below for 44 (32%) individuals. There were moderate correlations between rate of swallowing and disease severity, depression and cognition, but not between swallowing speed and disease duration. There was poor correlation between subjective reports of dysphagia and performance on the water swallow test. CONCLUSIONS: Swallowing problems are frequent in PD. Self-report of 'no difficulty' is not a reliable indicator of swallowing ability. Studies employing more-objective assessment of aspiration risk to compare with water swallow test performance are advocated.

Impaired attention predicts falling in Parkinson's disease.

BACKGROUND: Cognitive deficits, in particular deficits of attention and executive function, may affect postural sway and balance in Parkinson's disease (PD). Our objective was to determine whether measures of attention were associated with falls in a large cohort of subjects with PD studied prospectively. METHODS: Patients meeting UK PD Society Brain Bank Criteria were included. Assessment included UPDRS III and the Cognitive Drug Research computerised assessment battery (CDR) from which Power of Attention, Continuity of Attention, cognitive reaction time and reaction time variability were derived. Falls were assessed prospectively using monthly fall diaries returned over a year following baseline assessment. RESULTS: One hundred and sixty four subjects completed fall diary datasets. One hundred and three (63%) fell one or more times during the 12 month period. Regression analysis revealed an association of fall frequency with poorer Power of Attention and increased reaction time variability, which was retained after correcting for UPDRS scores. CONCLUSIONS: Reduced power of attention and increased reaction time variability are associated with increased fall frequency in PD. This has implications for the identification of those most at risk of falling, and for the management and prevention of falls in this patient group.

Frequency of orthostatic hypotension in a community based cohort of patients with Parkinson's disease.

The frequency of orthostatic hypotension (OH) in cohorts of patients recruited through hospital Parkinson's disease (PD) clinics ranges from 16% to 58%. However, hospital based cohorts may be subject to ascertainment bias. The aim of this study was to determine the frequency of OH in a community based population of PD patients and to determine the demographic features of patients with and without OH. Forty two (47%) of patients met the criteria for OH. Subjects with OH were older than those without OH, but there was no difference in PD disease duration or severity, MMSE or depression rating between the groups.

Diagnostic yield and development of a neurocardiovascular investigation unit for older adults in a district hospital.

BACKGROUND: Dizziness, syncope, and falls are common occurrences in elderly people. Neurocardiovascular investigation units aim to detect those patients who fall due to disturbances of blood pressure control or cardiac conduction. Specialist units have a high diagnostic yield in the investigation of these problems. Does this translate to less specialized centers? We report on the diagnostic findings of a district general hospital neurocardiovascular investigation unit. METHOD: A total of 120 consecutive patients over the age of 65 presenting to a single geriatrician were assessed. After a full history and physical examination, patients underwent neurocardiovascular investigation: blood pressure and heart rate response to active stand, carotid sinus massage, and 30-minute head-up tilt. RESULTS: The 120 patients assessed had a mean age of 78 years (range 66-94 years); in this group, 85 were women. Of these patients, 23% presented with falls, 14% with blackouts, and 30% with dizziness. The remaining 33% had overlap of symptoms. Neurocardiovascular investigations produced a diagnosis in 57% of the patients: 22% had cardioinhibitory carotid sinus syndrome (CSS): 15% had vasodepressor CSS; 29% had orthostatic hypotension; and 3% had vasovagal syncope. Thirteen percent had more than one neurocardiovascular abnormality, and 18% had benign positional vertigo. Five patients had postural instability causing falls. Hyperventilation syndrome, aortic stenosis, dysrhythmia, cervical spondylosis, and epilepsy each accounted for one case. Seventeen percent of the subjects remained undiagnosed after integrated neurocardiovascular assessment. CONCLUSION: Management of falls requires access to neurocardiovascular assessment. It is feasible to provide such a service in the district general hospital setting, with a comparable diagnostic yield to tertiary referral centers.