Cognitive impairments and depression in Parkinson's disease: a follow up study

Neuropsychiatry of the basal ganglia

This review aims to relate recent findings describing the role and neural connectivity of the basal ganglia to the clinical neuropsychiatry of basal ganglia movement disorders and to the role of basal ganglia disturbances in "psychiatric"' states. Articles relating to the relevant topics were initially collected through MEDLINE and papers relating to the clinical conditions discussed were also reviewed. The anatomy and connections of the basal ganglia indicate that these structures are important links between parts of the brain that have classically been considered to be related to emotional functioning and brain regions previously considered to have largely motor functions. The basal ganglia have a role in the development and integration of psychomotor behaviours, involving motor functions, memory and attentional mechanisms, and reward processes.

Quantification of the dopaminergic response in Parkinson's disease

BACKGROUND

Various investigators have developed complex quantitative procedures for objective assessment of parkinsonian motor impairment, since drawbacks of rating scales are interrater variability, subjective impression, insensitivity to subtle modifications.

OBJECTIVES

To determine whether standardized performance of inserting pegs (i) differentiates between parkinsonian subjects and healthy controls and (ii) reflects quantification of the dopaminergic response with rating scales within a levodopa challenge test design.

SUBJECTS AND METHODS

We used an easy-to-operate Purdue Pegboard-like apparatus, which measures the total time taken to insert 25 pegs from a rack into a series of appropriate holes by a computer to 100 ms accuracy, and simultaneous rating with part III of the Unified Parkinson's Disease Rating Scale for assessment of motor impairment in 28 idiopathic parkinsonian patients before and during a levodopa challenge test. Additionally we compared data of the instrumental task to age- and sex-matched healthy controls.

RESULTS

We found significant differences between parkinsonian subjects and controls and significant correlations to the rated severity of Parkinson's disease. Within-subject comparisons and correlation analysis demonstrated the ability of this tool to reflect scored motor improvement after intake of levodopa.

CONCLUSION

Inserting pegs provides an objective quantitative estimation of changes in motor impairment within a typical levodopa challenge test design.

Depressive symptom patterns in patients with Parkinson's disease and other older adults

Research on depression in Parkinson's disease (PD) has suggested that PD patients experience a qualitatively different depression from that of other older adults, endorsing fewer cognitive symptoms of depression (e.g., guilt, failure) and greater somatic (e.g., poor sleep) and mood symptoms (e.g., sadness, hopelessness); however, this has never been tested directly. In the present study, two PD groups, one with cognitive impairment (PD + CI; n = 26) and one without cognitive impairment (PD; n = 45), and three control groups of older adults were compared on measures of depressive symptomatology. The control groups included a physically disabled group (n = 46), a cognitively impaired group (CI; n = 21), and a healthy group (n = 50). Confirmatory factor analysis verified a four-factor model of depressive symptoms (Cognitive, Mood, Somatic, and Fatigue symptoms). Comparisons revealed that the PD group had a depressive-symptom pattern that was not significantly different from the disabled and healthy groups. The PD + CI group had a symptom pattern that was more similar to the CI group than to the PD group. Implications for the conceptualization of depression in older adults are discussed.

Neurobehavioral aspects of movement disorders

Cognitive, behavioral, affective, and psychiatric symptoms occur in almost all movement disorders. Diagnosis and management of movement disorders depends critically on an understanding of these neurobehavioral symptoms. This article reviews the neurobehavioral aspects of two representative movement disorders; Parkinson's disease and Huntington's disease.

Updated guidelines for the management of Parkinson's disease

New data on diagnosis, drug therapy, surgery and psychosocial concerns have emerged since the publication of the 1998 Guidelines for the Management of Parkinson's Disease. This article reviews new data and addresses issues left unanswered in the previous guidelines.

Depression in alpha-synucleinopathies: prevalence, pathophysiology and treatment

Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) are increasingly recognized as alpha-synucleinopathies, i.e. neurodegenerative disorders that share a common subcellular pathology characterized by alpha-synuclein abnormal aggregation. In the present review we focus on depression in alpha-synucleinopathies, discussing epidemiological, pathophysiological and treatment aspects of this frequently disabling clinical feature which may occur in PD, DLB and MSA alike.

Correlation between tapping and inserting of pegs in Parkinson's disease

BACKGROUND

Various investigators have developed complex quantitative instrumental procedures for objective assessment of parkinsonian motor impairment, since drawbacks of rating scales are interrater variability, subjective impression, and insensitivity to subtle modifications.

OBJECTIVES

To determine whether performance of inserting of pegs and tapping (i) correlates with each other (ii) differentiates between parkinsonian subjects and healthy controls and (iii) reflects severity of Parkinson's disease (PD).

SUBJECTS AND METHODS

In 157 previously untreated idiopathic parkinsonian patients and healthy controls, we measured (i) the total time taken to insert 25 pegs from a rack into a series of appropriate holes in a Purdue pegboard-like apparatus and (ii) the number of taps on a contact board with a contact pencil for a period of 32 seconds for assessment of fine motor skills.

RESULTS

Results of both tests correlated with each other, differed between parkinsonian subjects and controls and reflected scored severity of PD. Better correlation with intensity of PD was noted with the Purdue pegboard-like task.

CONCLUSION

Both tapping and inserting of pegs represent useful tools for objective evaluation of severity of PD. Peg insertion correlated better with disease severity. Both approaches may be useful in future clinical studies.

Neuropsychologic assessment of patients for movement disorder surgery

The neuropsychologic evaluation of patients under consideration for movement disorder surgery is recognized as being an essential component of the preoperative process. Patients with early-stage concomitant dementia must be identified and the relative risk of postoperative cognitive decline evaluated. Knowledge of the patterns of an individual's strengths and weaknesses might also be a factor in deciding on a neurosurgical procedure. Although the advent of pallidal deep brain stimulation (DBS) has possibly resulted in reduced risk of induced cognitive impairment, even this procedure has been associated with negative sequelae. DBS within the subthalamic nucleus is becoming the method of choice and this may lead to cognitive and behavioral compromise, especially in the elderly patient. The team considering the establishment of neurosurgical treatment is often at a loss to decide how much neuropsychologic testing is required to determine relative risks of cognitive or behavioral morbidity as a consequence of the procedure. A brief summary of expected outcome and of pertinent family process and psychodynamic issues are addressed. This article is intended to serve as a guide to permit clinicians to choose the appropriate length and depth of neuropsychologic assessment, but also to highlight the confounding factors often present in these patients.

Treatment of behavioural disturbances in Parkinson's disease

Behavioural disorders in Parkinson's disease can grossly be subdivided in primary disturbances and those which are related to drug treatment. Depression and anxiety are a common feature in parkinsonian patients. Both occur independently of drug treatment. In general, most current antidepressive and anxiolytic drugs could be administered in Parkinson's disease with the same precautions as in the normal population. However, in single case reports modern serotonin reuptake blockers in Parkinson's disease have been accused to worsen parkinsonian motor condition. Combinations of serotonin reuptake inhibitors with MAO-inhibitors like selegiline should be used with caution. In the case of cognitive decline firstly an underlying depression should be disclosed or if existent be treated. Depression seems to be the single most important factor associated with the severity of dementia and early antidepressant treatment seems to decrease cognitive decline in depressed parkinsonian patients. Anticholinergic medications should be discontinued since they may cause mental side effects. Sleep disorders in Parkinson's disease are mainly caused by nocturnal akinesia, which causes sleep fragmentation or altered dreaming and nightmares, which might be a side-effect of dopaminergic treatment. In the first case the administration of a controlled release preparation of levodopa at bedtime may be indicated. If the sleep disorder is considered to be due to dopaminergic medication, a reduction of long-term acting agents like modern dopamine agonists and controlled-release levodopa should be considered. In severe psychotic states related to drug treatment antiparkinsonian therapy must be carefully analysed and, if possible, reduced. If motor condition worsens and/or psychiatric symptoms do not improve, initiation with "atypical" neuroleptics like clozapine is indicated. The pharmacological and clinical properties of new antipsychotic drugs that can be used in Parkinson's disease are revised.

Neuropsychological prediction of dementia in Parkinson's disease

OBJECTIVE

To identify neuropsychological characteristics predictive of later dementia in Parkinson's disease.

METHODS

A comprehensive neuropsychological test battery was administered to a cohort of 89 initially non-demented patients with Parkinson's disease consecutively enrolled at a specialised Parkinson's disease clinic. They were reassessed after a mean of 3.5 years for the diagnosis of dementia. The Cox proportional hazards model was used to identify baseline characteristics predictive of dementia.

RESULTS

Only four of the baseline clinical characteristics of Parkinson's disease and neuropsychological variables remained independently linked to subsequent development of dementia: the age of onset of Parkinson's disease (>60 years; relative risk (RR) 4.1, 95% confidence interval (95% CI) 1.8-24.0, p<0.03), the picture completion subtest of the Wechsler adult intelligence scale (score<10; RR 4.9, 95% CI 1.0-24.1, p<0.02), the interference section of the Stroop test (score<21; RR 3.8, p=0.08), and a verbal fluency task (score<9; RR 2.7, 95% CI 0.8-9.1, p=0.09). Depressive symptoms and the severity of motor impairment were not predictive of dementia.

CONCLUSION

These features are different from the neuropsychological characteristics predictive of Alzheimer's dementia in healthy elderly people (mainly memory and language performance). They are in keeping with the well known specificity of the impairments in Parkinson's disease for visuospatial abilities and difficulties in inhibiting irrelevant stimuli. It is postulated that the composite nature of the picture completion subtest, involving several cognitive abilities impaired in Parkinson's disease, explains its sensitivity.

Tone duration discrimination in Parkinson's disease

Patients with Parkinson's disease (PD) and healthy controls took a computerized test of tone duration discrimination (TDD) using pairs of tones of 0.4-1.6 sec duration, presented at intervals of 0.5-4 sec. In PD patients as well as controls, TDD was impaired by even slight degrees of cognitive deterioration. PD yielded impaired TDD in females, but not in males. This suggests that the dopamine-powered biological clock, which is vulnerable to PD, is more important for the processing of durations in the 1-sec range in women than in men.

Stressful life events and depressive symptoms among the elderly. Evidence from a prospective community study

We examined the effect of a series of common stressful life events on change in depressive symptoms among the elderly. The subjects were 1,962 noninstitutionalized people 65 years of age or older from the New Haven EPESE project. Multivariate regression models revealed that 8 of 11 stressful life events examined predicted change in depressive symptoms at follow-up (1985) after controlling for baseline depressive symptoms age, socioeconomic factors, functional status, and chronic conditions. In addition, the total number of stressful life events was significantly associated with higher CES-D depression scores. A dose-response relationship between cumulative life event stress and change in depressive symptoms was also shown. These results suggest that certain common life event stressors may have an impact on mental health, both singly and in combination.

Relationship between cognitive impairments, event-related potentials, and motor disability scores in patients with Parkinson's disease: 2-year follow-up study

We studied event-related potentials and the cognitive state for 2 years in 29 patients with Parkinson's disease (PD). Of those patients, 11 were at stage II and 18 were at stage III at initial assessment, as measured on the Hoehn and Yahr scale. The peak latency of P300 in patients at stage III was significantly prolonged, as compared with that in age-matched normal controls or PD patients at stage II. There was no significant change in P300 latency among patients whose motor ability remained unchanged at stage II or stage III during follow-up period. The mean P300 latency prolonged significantly in patients whose motor ability worsened from stage III to stage IV. The cognitive state in the patients with PD was characterized by impairment in the categories of orientation, recall and constructional ability. The degree of impairment of these items increased as the motor disability increased. These results suggest that cognitive dysfunctions and abnormality of P300 latency increased as the motor disabilities progressed.

The motor performance test series in Parkinson's disease is influenced by depression

The Motor Performance Test Series (MPTS) is widely used for treatment control in Parkinson's disease (PD). To elucidate the possible influence of depression on the fine motor skills in PD, 54 patients with idiopathic PD were investigated with the MPTS. 27 patients with major intensity of depression were compared to 27 age and motor disability matched patients with minor symptoms of depression, evaluated by the Zung depression scale. As determined by the subtest aiming, a significant lower ability for precise, quick complex arm-hand movements in depressed Parkinsonian patients was found. This result may be explained partly by motivation deficits in depressed patients with PD. On the other hand impairment of special motor loops including frontal lobe projections to specific thalamic subnuclei or to the caudate nucleus may cause disturbances of the subtest aiming in depressed Parkinsonian patients. On the basis of these findings impaired aiming may be explained by diminished ability for complex, semivoluntary movements in depressive Parkinsonian patients. The influence of psychiatric comorbidity on MPTS subtest aiming has to be considered in further therapy studies using evaluation of motor deficits by MPTS.

Association between presenting motor symptoms and the risk of cognitive impairment in Parkinson's disease

Neuropsychological data collected from two groups of patients with idiopathic Parkinson's disease (n = 50, 159) were analysed to investigate the association between presenting motor symptoms determined from retrospective chart review and the risk of cognitive impairment. Presenting motor symptoms were abstracted from the medical records and coded by type, location, and laterality. Longitudinal data on changes in the maximum speed of voluntary arm movements were available for a subsample of patients. Bilateral (v unilateral) presentation was associated with an increased risk of cognitive impairment an average of nine years after onset of disease as measured by memory tests and the mini-mental state examination. A higher rate of decline of arm movement speed was also predictive of greater memory dysfunction. The type, side (left v right), and location (lower v upper extremity) of the presenting symptoms were not, however, consistently associated with the risk of cognitive impairment later in the course of the disease.

Unified Parkinson's Disease Rating Scale characteristics and structure. The Cooperative Multicentric Group

Our purpose was to verify some basic aspects of validation of the Unified Parkinson's Disease Rating Scale (UPDRS). One hundred and sixty-seven Parkinson's disease (PD) patients were included. Group A (n = 40) was simultaneously assessed by five raters who applied the UPDRS and other PD rating scales (PDRS). A set of timed tests, the Mini-Mental State Examination (MMSE), and the Hamilton Scale for Depression (HSD) were administered by an independent examiner. Group B (n = 127) was individually assessed through the UPDRS and the other PDRSs by one neurologist in four different hospitals. The UPDRS was administered in 16.95 +/- 7.98 min. The internal consistency was high (Cronbach's alpha = 0.96). Nevertheless, the items related to depression, motivation/initiative, and tremor were scarcely consistent. The Interrater reliability was satisfactory (all the items had k > 0.40). There was a high correlation of the UPDRS with the Hoehn and Yahr staging (rs = 0.71; p < 0.001) and some timed tests (finger tapping; arising from chair), but also with the MMSE and HSD (rs = 0.53; rs = 0.64; p < 0.001). The convergent validity with the other PDRS (Intermediate Scale and Schwab and England Scale) was very high (rs = 0.76-0.96; p < 0.001). The factor analysis identified six factors that explained 59.6% of the variance. The dimension "tremor" showed a remarkable independence. The UPDRS is a multidimensional, reliable, and valid scale, with some inconveniences derived from its internal consistency, discriminant validity, and pragmatic application.

Alzheimer's disease and idiopathic Parkinson's disease coexistence

Idiopathic Parkinson's disease (IPD) and Alzheimer's disease (AD) are common neurologic diseases of old age. Parkinson syndrome is easy to recognize even at an early stage, but identifying early AD is often difficult. Accurate clinical diagnosis is important for assigning the prognosis and for studies aimed at assessing the efforts to slow down progression of these diseases. During 22 years, we identified six patients who had clinical features of parkinsonism and dementia and who at autopsy had both IDP and AD and 20 parkinsonian patients without dementia who at autopsy had only IPD. The clinical profile in these two groups was compared. The onset of Parkinson syndrome in the patients with dual pathology had a bimodal distribution--before or after age 65 years. In the three cases with onset before age 65 years, there was sequential evolution of IPD and AD. In contrast, those older than 65 years at onset manifested the clinical features of both IPD and AD simultaneously. The mode of onset and the dominant parkinsonian features in the three patients with sequential clinical evolution were similar to those seen in the nondemented IPD cases; however, lack of self-confidence and inability to make decisions resulted in considerably greater functional disability than could be accounted for by parkinsonism alone. These characteristics may be helpful in early recognition of dual IPD and AD pathology. Psychiatric side effects of levodopa therapy were more common in those with dual pathology than in those with IPD alone.

A prospective longitudinal study of depression, cognitive decline, and physical impairments in patients with Parkinson's disease

A consecutive series of 105 patients with Parkinson's disease were examined for the presence of affective disorders, cognitive deficits, and impairments in activities of daily living (ADLs); 92 received the same evaluation 12 months after the initial examination. On the basis of the initial psychiatric findings, patients were divided into major, minor, and non-depressed groups. Patients with major depression showed a significantly greater cognitive decline, deterioration in ADLs, and further advance through the Hoehn and Yahr stages than patients with either minor depression or no depression.

The etiology of depression in Parkinson's disease patients

Depression is the major psychiatric complication of Parkinson's disease, and it occurs in approximately one-third of all cases. Diagnosis of depression is complicated by the overlap of depressive and parkinsonian symptoms. Its etiology is not fully understood but involves changes in dopamine and serotonin. Depression has significant clinical impact; depressed patients are more disabled (less independent). The depressive symptoms respond to treatment with antidepressants and electroconvulsive therapy.