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In healthy individuals and those with insomnia, poor sleep quality is associated with decrements in performance on tests of cognition, especially executive function. Sleep disturbances and cognitive deficits are both prevalent in Parkinson's disease (PD). Sleep problems occur in over 75% of patients, with sleep fragmentation and decreased sleep efficiency being the most common sleep complaints, but their relation to cognition is unknown. We examined the association between sleep quality and cognition in PD. In 35 non-demented individuals with PD and 18 normal control adults (NC), sleep was measured using 24-hr wrist actigraphy over 7 days. Cognitive domains tested included attention and executive function, memory and psychomotor function. In both groups, poor sleep was associated with worse performance on tests of attention/executive function but not memory or psychomotor function. In the PD group, attention/executive function was predicted by sleep efficiency, whereas memory and psychomotor function were not predicted by sleep quality. Psychomotor and memory function were predicted by motor symptom severity. This study is the first to demonstrate that sleep quality in PD is significantly correlated with cognition and that it differentially impacts attention and executive function, thereby furthering our understanding of the link between sleep and cognition.

The etiology of sleep problems in Parkinson disease (PD) is not well understood, as they may arise from the pathology of the disease or from other disease-related factors such as motor dysfunction, dopaminergic medication, and mood disturbances. The aim of this study was to investigate factors associated with sleep, including disease-related variables such as motor symptom severity, dose of medication, and mood and disease subtypes. Thirty-five nondemented patients with PD were included. Sleep was measured using 24-hour wrist actigraphy over a 7-day period, during which time participants kept a sleep diary. Subjective sleep and arousal questionnaires included the PD Sleep Scale and Epworth Sleepiness Scale. Motor symptom severity and dopaminergic medication were significantly related to measures of sleep quality. Sex differences in sleep quality were found, with men having worse sleep quality and more excessive daytime sleepiness than women. We also found that actigraphy may serve as a useful tool for identifying individuals with possible rapid eye movement behavior disorder, a sleep disorder that has important implications in early detection of PD.

Parkinson's disease (PD) presents with extensive heterogeneity in symptomatology, inviting examination of disease subtypes. One significant categorization is by whether patients present at onset with tremor as the dominant symptom (TD) or with nontremor symptoms (NTD). We examined differences in quality of life between TD and NTD patients using the Parkinson's Disease Questionnaire-39 (PDQ-39), correlating performance with aspects of motor function as indexed by the Unified Parkinson's Disease Rating Scale (UPDRS). Participants included 35 nondemented individuals (19 TD, 16 NTD) matched on clinical and demographic characteristics. NTD had significantly lower overall PDQ-39 scores, particularly for the mobility subscale. Several UPDRS subscale scores significantly correlated with quality of life, especially for NTD. Further, the correlations were driven by nontremor type symptoms, even in TD patients. Determining reliable subtypes of PD may aid in prognosis and treatment optimization, thereby enhancing quality of life in afflicted individuals.

Background: Previous studies have demonstrated an association between white matter hyperintensities (WMH) and cognitive performance primarily in Caucasian samples, limiting generalizability to other ethnic and racial groups. This study investigated the association of WMH and cognition in an ethnic and racial minority cohort (Omni) of the Framingham Heart Study and compared these results to the Caucasian (Offspring) cohort., Methods: Quantitative brain MRI and neuropsychological evaluations were performed on stroke- and dementia-free participants. Cognitive assessment included verbal memory, visuospatial memory and organization, language, and executive functioning. Linear regression models were conducted to assess the association between WMH and cognitive function., Results: The Omni group presented with demographic factors that significantly differed from those of the Offspring group: they were younger, but had more stroke risk factors such as hypertension. In the Offspring group, WMH volume was significantly associated with poorer performance on tests of executive function and visual organization. No significant associations between WMH and cognitive measures were found in the Omni group, but no differences (significant interaction terms) were seen between the regression coefficients., Conclusions: The Omni cohort had greater variability in factors that may mediate the association of WMH and cognition. More research is needed to investigate how stroke risk factors impact on the occurrence of WMH and its association with cognition in more diverse cohorts., (Copyright 2010 S. Karger AG, Basel.)

Objective: Patients with Parkinson's disease (PD) present with a variety of non-motor symptoms including sensory complaints and mood disturbances. In the current pilot study, we aimed to explore pain complaints and the association between mood and pain in PD. We hypothesized that pain ratings would be elevated in patients with PD relative to controls. As PD is lateralized at onset and studies have found lateralization of some non-motor symptoms in PD, we also hypothesized that PD patients would exhibit differing pain profiles depending on side of onset of the disease., Methods: Twenty-three PD patients (11 right-onset (RPD), 12 left-onset (LPD) disease), and 11 control participants (CS) completed a mood questionnaire (Depression Anxiety Stress Scale; DASS) as well as the short form of the McGill Pain Questionnaire., Results: Both PD groups reported higher present pain intensity scores (p = 0.001), more evaluative pain intensity (p = 0.02), and more overall pain (p = 0.02) than control participants. There was a significant association between mood and all of the McGill pain ratings in the LPD patients, with those reporting more mood symptoms rating higher on all pain scales (all p-values < 0.001). This association was not found in the RPD group., Conclusions: Our results suggest an association between mood and pain in patients with PD that may be related to the differential contribution of right-hemispheric neural networks in processing of mood and pain states. These findings merit further investigation into the relation between mood and pain in patients with PD.

Purpose. To assess the impact of clinical variables on social skills and behaviors in Parkinson's disease (PD) patients and patient versus examiner estimates of social functioning. Methods. Twenty-eight patients with PD and 32 controls with chronic disease were assessed with a battery of neuropsychologic, personality, mood, and social function tests. Results. Patients' estimates of their own social functioning were not significantly different from examiners' estimates. The impact of clinical variables on social functioning in PD revealed depression to be the strongest association of social functioning in PD on both the patient and the examiner version of the Social Adaptation Self-Evaluation Scale. Conclusions. PD patients appear to be well aware of their social strengths and weaknesses. Depression and motor symptom severity are significant predictors of both self- and examiner reported social functioning in patients with PD. Assessment and treatment of depression in patients with PD may improve social functioning and overall quality of life.

Objective: To relate sleep disturbances in Parkinson disease (PD) to hemispheric asymmetry of initial presentation., Background: Sleep disturbances are common in PD arising from the neurodegenerative process underlying the disease, which is usually lateralized at onset. Patients with left-side Parkinson disease onset (LPD: right hemisphere dysfunction) exhibit reduced vigilance relative to those with right-side Parkinson disease onset (RPD: left hemisphere dysfunction), leading us to hypothesize that sleep-related disturbances, particularly excessive daytime sleepiness, would be more severe for LPD than for RPD., Methods: Thirty-one nondemented participants with PD (17 RPD and 14 LPD) and 17 age-matched control (CO) participants with chronic health conditions were administered the Parkinson Disease Sleep Scale and polysomnography was performed on a subset of the PD participants., Results: Both PD subgroups exhibited more nighttime motor symptoms than the CO group, but only LPD endorsed more nocturnal hallucinations and daytime dozing. Controlling for mood additionally revealed more vivid dreaming in LPD than RPD. There were no significant differences between LPD and RPD on measures of sleep architecture., Conclusions: Increased dreaming, hallucinations, and daytime somnolescence in LPD may be related to changes in right-hemisphere neural networks implicated in the generation and control of visual images, arousal, and vigilance. Our results underscore the need to consider side of onset in regard to sleep disturbances in PD.

Background: The objective of this study was to compare total costs of care and its major components for community-living patients with Alzheimer's disease (AD) or dementia with Lewy bodies (DLB). This cross-sectional analysis of baseline data from the Predictors II Study took place in three university-based AD centers in the U.S., Methods: Community-living patients clinically diagnosed with probable AD (n = 170) or DLB (n = 25) with a modified Mini-Mental State examination (mMMS) score > or =30, equivalent to a score of approximately > or =16 on the Folstein Mini-Mental State Examination (MMSE), participated in this study. Patient and informant reported on patients' use of direct medical care, direct nonmedical care, and informal care. Patients' clinical and demographic characteristics included global cognitive status (measured by MMSE), functional capacity (measured by Blessed Dementia Rating Scale), psychotic symptoms, behavioral problems, depressive symptoms, extrapyramidal signs, comorbidities, age, and sex. Costs were compared by using covariate matching methods., Results: Unadjusted total costs and direct medical costs were not significantly different between AD and DLB patients. Compared with AD patients, unadjusted indirect costs were significantly higher and unadjusted direct nonmedical costs were significantly lower among DLB patients. After adjusting for age, sex, cognitive and functional status, differences in all cost components between DLB and AD patients were no longer statistically significant., Conclusions: Apparent cost differences were largely attributed to differences in patients' cognitive and functional status. However, the small sample size for DLB patients might have limited power to detect statistically significant differences in costs of care between these groups.

Background: Although dementia with Lewy bodies (DLB) may be one of most common forms of dementia, relatively little is known about its cognitive and functional course., Objective: To compare change over time in general cognitive status, memory test performance, psychiatric symptoms, neurological signs, and functional abilities in patients with probable DLB and probable Alzheimer disease (AD)., Design: Twenty-eight patients who met diagnostic criteria for DLB were recruited into the study from 3 sites. Patients with AD (n = 55) were selected from a larger cohort and matched 2 to 1 to the patients with DLB on age and baseline global cognitive status. Patients were followed up at 6-month intervals for an average of 6.2 visits and assessed at each visit with tests of global cognitive functioning and verbal learning and memory and measures of psychiatric, neurological, and functional status., Results: At the baseline evaluation, patients with DLB performed more poorly on a measure of constructional praxis and all measures of functional status. They also had more severe psychiatric symptoms and neurological signs than the AD group. Despite these initial differences, generalized estimating equations applied to regression analyses with repeated measures determined that the only difference between the 2 groups in change in cognitive test performance was on a measure of recognition memory; patients with AD declined, while patients with DLB remained relatively stable. Patients with DLB had relatively stable behavioral symptoms and visual illusions, whereas patients with AD had a significant increase in these symptoms over time. Neurological and functional changes over time were similar in the 2 groups., Conclusions: Both baseline and longitudinal differences between patients with DLB and patients with AD were noted; these have implications for clinical diagnosis and treatment.

Both reduced hippocampal volume and cognitive alterations have been found in posttraumatic stress disorder (PTSD). The purpose of this article was to examine the relationship between hippocampal volume, combat exposure, symptom severity, and memory performance in a sample of combat veterans with and without a history of PTSD. Subjects were 33 male veteran volunteers (16 PTSD+, 17 PTSD-) who underwent an MRI and neuropsychological testing with the California Verbal Learning Test (CVLT), a measure of declarative memory. Relationships between hippocampal volume (i.e., right + left hippocampal volume/whole brain volume) and performance on the CVLT were determined using partial correlational analysis controlled for age and Wechsler Adult Intelligence Scale, Third Edition (WAIS-III) vocabulary scores. Percent hippocampal volume for the entire sample was positively associated with several aspects of memory performance as reflected by the CVLT. In the PTSD+ group, CVLT performance was negatively correlated with lifetime, but not current CAPS symptoms. CVLT performance appears to be strongly correlated with hippocampal volume in a group of trauma survivors with and without PTSD. Insofar as CVLT performance in the PTSD group was negatively associated with worst episode, but not to current PTSD symptoms, memory performance in combat veterans may reflect some aspect of risk related to the magnitude of the psychological response to trauma, rather than current symptoms that may be interfering with cognitive performance. It will be of interest to study cognitive abilities that may relate to the likelihood of specific PTSD symptoms and to track changes in CVLT performance and hippocampal volume over time in persons with and without a history of trauma exposure.

Rationale: Holocaust survivors with PTSD appear to show an accelerated aging effect as evidenced by their performance on tests of explicit memory, and also show more exaggerated patterns on age-related alterations in cortisol release over the diurnal cycle than Holocaust survivors without PTSD and nonexposed subjects. To investigate the implications of age-related HPA axis alterations on cognition, we examined correlations between parameters reflecting circadian cortisol release and implicit and explicit memory performance., Methods: Nineteen Holocaust survivors with PTSD (7 men, 12 women), 16 Holocaust survivors without PTSD (7 men, 9 women), and 28 non-exposed healthy comparison subjects (13 men, 15 women) collected salivary samples at six times over the diurnal cycle, and were tested with Paired Associates and Word Stem Completion Tests., Results: Negative correlations were observed between several measures of salivary cortisol concentrations and explicit memory in Holocaust survivors with PTSD after adjusting for IQ, years of education and current age reflecting poorer performance in association with higher cortisol levels. This relationship was absent in Holocaust survivors without PTSD and in demographically-comparable subjects who were not exposed to the Holocaust or other extremely traumatic events., Conclusion: The significantly different relationship between cortisol and memory performance in these groups suggests that the neuropsychological impairments observed in Holocaust survivors with PTSD may reflect an interaction of PTSD and aging effects.

The California Verbal Learning Test (CVLT) was administered to examine learning and memory performance in aging combat veterans with (n = 30) and without PTSD (n = 20), and veterans unexposed to combat (n = 15). Combat veterans with PTSD (PTSD+) showed many impairments compared to non-exposed veterans, but only long-delay free recall consistently discriminated the PTSD+ group from combat-exposed subjects without PTSD (PTSD-), when data were corrected for subscale scores on the WAIS (Vocabulary, Block Design). Alterations in total learning were associated with PTSD when controlling for substance abuse and depression. Two contrast measures, proactive interference and recognition hits, distinguished combat from noncombat veterans, and may be related to trauma exposure. Impairments in total learning are similar to what has been observed in Holocaust survivors. However, increased severity of rapid forgetting may be a specific alteration in older combat veterans, likely reflecting aspects of both combat exposure and aging.