Depression, intellectual impairment, and Parkinson disease

Mixed neurologic and psychiatric disorders: pharmacological issues

The number of patients with mixed neurologic and psychiatric disturbances is large. The psychiatric disturbances are often atypical in presentation and fit poorly into standard psychiatric nomenclature. They can be difficult to treat using standard psychopharmacologic approaches. This report reviews the impact of brain dysfunction on the use of conventional and nonconventional psychotropic agents in this mixed population.

Amine accumulation: a possible precursor of Lewy body formation in Parkinson's disease

It is now well recognized that the hypothalamus is an important site of neuropathology in Parkinson's disease (PD). Lewy bodies, a marker of nerve cell degeneration and a pathological hallmark of PD, have been observed frequently in the hypothalamus of PD patients by Lewy (1923) and other investigators and confirmed by more recent systematic studies by Langston & Forno (1978). Both Lewy and Langston & Forno found a predilection of Lewy body formation in specific hypothalamic nuclei with the tuberomammillary, lateral, and posterior areas containing by far the highest average counts per nucleus. Selective vulnerability of the tuberomammillary, lateral, and posterior hypothalamic cell groups to degeneration has been observed also in aging, postencephalitic Parkinsonism, Alzheimer's disease, and schizophrenia. The susceptibility of these particular nuclei to degenerative changes including Lewy body formation is not presently understood nor are the mechanisms by which Lewy bodies are formed in PD and other CNS disorders. Accumulation of amines, a pathological process which follows degeneration of catecholamine-containing neurons in experimental animals, also occurs most frequently in the lateral and posterior hypothalamic areas. In the present communication we propose that in PD, amine accumulation may be a precursor to Lewy body formation and that the susceptibility of certain hypothalamic areas to Lewy body formation may be related to their propensity to accumulate amines. Furthermore, the frequent co-existence of Lewy bodies and Alzheimer's neurofibrillary tangles in the lateral and posterior hypothalamic nuclei suggest that they may share a common pathogenetic etiology. If confirmed, this hypothesis may provide an experimental model by which the formation of Lewy bodies and neurofibrillary tangles may be investigated.

The subcortical dysfunction hypothesis of memory deficits in depression: neuropsychological validation in a subgroup of patients

The subcortical dysfunction hypothesis of verbal learning and memory deficits in depression was evaluated by comparing the memory test profiles of unipolar depressives (n = 40) and bipolar depressives (n = 9) with those of patients with a prototypical subcortical dementia (Huntington's disease, HD), patients with a prototypical cortical dementia (Alzheimer's disease, AD), and normal controls. In a discriminant function analysis that well-differentiated the HD, AD, and normal subjects, it was found that 28.6% of the depressed patients were classified as HD patients (DEP-HD subjects), 49.0% were classified as normals (DEP-N subjects), none were classified as AD patients, and 22.4% were not well-classified. The DEP-HD group closely resembled the HD group on additional indices of verbal learning and memory, and differed from the DEP-N group, which strongly resembled the normal control group. DEP-N patients also performed significantly better than DEP-HD patients on a number of other neuropsychological tests (e.g., WAIS-R Digit Symbol, category fluency, Trail Making Test Part B). The findings provide support for the subcortical dysfunction hypothesis, but only for a subgroup of depressed patients. Implications for differentiating depressive "pseudodementia" from AD are discussed.

The mini-mental state examination: a comprehensive review

OBJECTIVE

The purpose of this paper is to provide a comprehensive review of information accumulated over the past 26 years regarding the psychometric properties and utility of the Mini-Mental State Examination (MMSE).

PARTICIPANTS

The reviewed studies assessed a wide variety of subjects, ranging from cognitively intact community residents to those with severe cognitive impairment associated with various types of dementing illnesses.

MAIN OUTCOME MEASURES

The validity of the MMSE was compared against a variety of gold standards, including DSM-III-R and NINCDS-ADRDA criteria, clinical diagnoses, Activities of Daily Living measures, and other tests that putatively identify and measure cognitive impairment.

RESULTS

Reliability and construct validity were judged to be satisfactory. Measures of criterion validity showed high levels of sensitivity for moderate-to-severe cognitive impairment and lower levels for mild degrees of impairment. Content analyses revealed the MMSE was highly verbal, and not all items were equally sensitive to cognitive impairment. Items measuring language were judged to be relatively easy and lacked utility for identifying mild language deficits. Overall, MMSE scores were affected by age, education, and cultural background, but not gender.

CONCLUSIONS

In general, the MMSE fulfilled its original goal of providing a brief screening test that quantitatively assesses the severity of cognitive impairment and documents cognitive changes occurring over time. The MMSE should not, by itself, be used as a diagnostic tool to identify dementia. Suggestions for the clinical use of the MMSE are made.

Event-related potentials (ERPs) during repetition priming in Alzheimer's patients and young and older controls

Although memory tested explicitly (e.g., recognition) is clearly deficient in the early stages of Alzheimer's disease, it is less clear if memory tested implicitly is similarly affected. To assess this, event-related potentials (ERPs) were recorded during a word-repetition priming paradigm, with semantic and orthographic orienting tasks, from 10 patients with mild probable Alzheimer's disease (PAD; mean age of 70.6), 10 young (24.1) and 10 older (69.8) controls. The extent of priming by word repetition was assessed using the new minus old ERP repetition effect. The young and older control groups showed clear ERP repetition effects that were larger during semantic than orthographic blocks. Although the PAD patients displayed the same general trends, their ERP repetition effects were not nearly as marked when compared to controls. To the extent that the ERP repetition effect recorded during this repetition priming paradigm is a measure of implicit performance, the data suggest that memory assessed in this fashion is spared in at least some Alzheimer's patients in the early stages of the disease.

Event-related potential investigations of cognitive development and aging

Comparison of the results of the studies of cognitive development and normal aging suggests a large degree of commonality in both behavioral and ERP effects across a wide age range. Whether measured in young children, adolescents, young, middle-aged or elderly adults, the size of the ERP repetition effect did not differ among the various age groups. This was true whether memory was tested directly during continuous recognition or indirectly during variants of semantic categorization tasks. Similarly, in the studies of adult aging, the degree of RT facilitation during the semantic task did not differ with age and, in both the studies of cognitive development and aging, the degree of RT prolongation during the explicit tasks did not appear to differ as a function of age. Moreover, in the studies of adult aging, the effects of three versus two exposures of a word assessed in the PM session (TABLE 1), modulated RT similarly in all three age groups. These data argue for continuity of information processing across a very wide age range during both direct and indirect memory tasks, when retention is assessed during the recognition (for explicit testing) and repetition (for implicit testing) phases of the task. Since ERP and RT modulation do not appear to differ with age during the retrieval phases of these experiments, how can the performance differential seen in young children and older adults be explained? Some evidence comes from the ERP data recorded during the study phases of our explicit tasks. During continuous recognition, both young children and elderly adults did not show the typical subsequent "memory effect." In the case of the children, the subsequently unrecognized ERP was larger than the subsequently recognized ERP, whereas for the older adults, there was no difference between these two ERPs. Moreover, during these same tasks, the young children did show the "crossover" (new greater than old) pattern for slow wave activity, whereas the older adults did not. Since these ERP findings were obtained during the acquisition phase (i.e., to new items that had to be encoded for subsequent retrieval), the data argue for encoding difficulties as one means of explaining the performance differences seen at the two ends of the age spectrum. However, since the older adults displayed a different new/old pattern for slow wave activity, the two age groups may differ qualitatively in the strategies employed to encode items for subsequent retrieval.(ABSTRACT TRUNCATED AT 400 WORDS)

Control of tremor and involuntary movement disorders by chronic stereotactic stimulation of the ventral intermediate thalamic nucleus

The authors report on the long-term results of chronic stereotactic stimulation of the ventralis intermedius thalamic nucleus performed in 14 cases of disabling and intractable tremor. There were 10 patients with parkinsonian tremor and four with essential tremor. Three of the 10 parkinsonian patients had previously undergone contralateral thalamotomy. Tremor was assessed by clinical evaluation, surface electromyography, accelerometer, and videotape recordings before and after stimulation. The deep-brain electrode was implanted in the ventralis intermedius nucleus according to stereotactic procedure and connected to a subcutaneous pulse generator after a stimulation test period. Tremor suppression or reduction was obtained in all cases with high-frequency (130 Hz) stimulation. Marked functional improvement was maintained in 11 patients with a mean follow-up interval of 17 months. Levodopa-induced dyskinesias observed in five parkinsonian patients prior to surgery were improved or suppressed in four cases by thalamic stimulation. Stimulation was continued during the day and stopped at night in eight cases. Six patients were stimulated night and day to avoid a rebound effect which appeared as soon as the pulse generator was stopped. The only side effects were hand tonic posture in one case and persistent paresthesia in another case. The mechanism of action of this attractive treatment may be a functional alteration of the thalamic discharging area. The authors conclude that this technique is a good alternative to thalamotomy, especially when the risks of high-frequency coagulation are severe in frail and older patients.

Akinesia: a syndrome common to parkinsonism, retarded depression, and negative symptoms of schizophrenia

A distinct hypokinetic syndrome appears to exist across several different neuropsychiatric diagnoses, involving (1) slowed motor activity with difficulty initiating and sustaining behaviors, (2) anhedonia with depressed mood and reduced affective range, and (3) cognitive impairment. Specifically, three well-recognized states--parkinsonism, retarded depression, and the negative symptoms of schizophrenia--prominently feature the components of this syndrome, and reduced dopamine turnover in the brain has been hypothesized to play a part in the pathophysiology of each. While aspects of this conceptualization remain controversial, it generates testable hypotheses that could have implications for the understanding and treatment of these states.

The psychogeriatrician's view: management of chronic disability in the community

Psychiatric services for elderly people are based on principles which are relevant to the management of chronic disorders such as Parkinson's disease. Psychological and biological factors are closely intertwined in dementia, as they are in PD. Although medical diagnosis is important the emphasis is on continuing support. The aim is to provide services within the community where they are needed, and to acknowledge the importance of carers and family for assessment and management.

Activity and acceptability of piribedil in Parkinson's disease: a multicentre study

Several controlled trials have shown that the dopamine agonist, Trivastal (piribedil), is active in the treatment of Parkinson's disease, particularly with regard to tremor. To determine its efficacy as monotherapy in patients previously untreated with levodopa, a 3-month multicentre study was conducted with Trivastal 50 mg LP in 113 patients with idiopathic Parkinson's disease. The study population consisted of 66 men and 47 women, aged 63.1, SD 0.6 (43-79) years with a 2.1, SD 0.2 (1-15) year history of Parkinson's disease. Mean disease stage was 1.82 (1-4) by the Hoehn and Yahr classification. Tremor was the predominant clinical feature in 42 patients; the remaining 71 patients displayed the full parkinsonian syndrom. Trivastal 50 mg LP was prescribed stepwise up to doses of 150-250 (207, SD 6.4) mg/day at the end of 3 months. No concomitant anti-parkinsonian medication was given. Patients were clinically assessed at 1, 2 and 3 months on the Webster scale, a specific tremor scale and the HARD depression scale. Mean results were as follows in the 90 patients completing the study. On the Webster scale, tremor fell from 1.7 to 1 (-41%, P less than 0.001), bradykinesia from 1.5 to 0.8 (-47%, P less than 0.001) and rigidity from 1.3 to 0.9 (-31%, P less than 0.001); on the specific scale, rest tremor decreased in daily duration and amplitude from 3.9 to 2.4 (-39%, P less than 0.001) and from 2.9 to 2.1 (-35%, P less than 0.001), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Some clinical aspects of late onset parkinsonism

Thirty-six parkinsonian patients were selected by age of onset of over 70 and a minimum of five years duration of illness. The mean age of onset was 73.5 years and 30 patients were still alive after a mean of 7.2 years. We found that late onset Parkinson's disease has a relatively benign course with more "axial symptoms" especially dysarthria, freezing and postural instability. Dyskinesias and fluctuations are rare and dementia occurs in few patients in spite of their old age.

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.

Psychological factors affecting neurological conditions. Depression and stroke, multiple sclerosis, Parkinson's disease, and epilepsy

As a contribution to the proposed revision of the DSM-III-R category "Psychological Factors Affecting Physical Condition" for DSM-IV, this article reviews the history of how the relationship of psychiatric illness to neurological illness has been understood with respect to depression. Since both psychiatric and neurological illness are aspects of brain functioning, any statement of the relationship of these categories entails certain epistemological assumptions, some of which have undergone considerable change and rapid evolution in the course of the last century.

The delayed neurobehavioural sequelae of traumatic brain injury

This is a comprehensive review of the late-occurring effects of traumatic brain injury (TBI). It appears that TBI increases the risk over basal rates for the general population, to this degree: for depression, by a factor of five or 10; for seizures, by two to five; for psychotic disorders, by the same factor; and for dementia, by four or five. Severe TBI, or injuries with special characteristics, may increase the risk of delayed sequelae even further. One is not able, at this point, to estimate the relative occurrence of a newly described entity--delayed amnesia. An initial TBI increases the risk for subsequent TBI, by a factor of two. A second TBI increases the risk of yet another TBI eightfold.

Depression antedating the onset of Parkinson's disease

Neurological and depressive symptoms in a subtype of Parkinson's disease (PD), in which a depressive state precedes the clinical manifestation of neurological symptoms, were examined on the basis of clinical observations for 3 years or more. PD, in which depression preceded, was different from PD with preceding neurological symptoms, in the severity of not only neurological but also depressive symptoms. These results suggest that PD in which depression precedes neurological symptoms is a specific subtype of PD. It was speculated that the differences in clinical symptoms might be due to a biological background, in particular the dopaminergic system.

Cardiac deceleration and E-wave brain potential components in young, middle-aged and elderly adults

Event-related potentials (ERPs), heart rate, and behavioral data were recorded from young, middle-aged, and elderly adults during an S1-S2 recognition memory paradigm. Anticipatory and evoked cardiac decelerations decreased significantly with age, as did the accuracy of recognition memory. The E-wave prior to S2 did not differ with age, however, and was not correlated with heart rate deceleration in any age group. Correlations between physiological measures and performance were weak in all groups. Taken together, the data provide little support for the hypothesis that the poorer recognition memory of older adults is related to an increasing uncoupling of E-wave and anticipatory heart rate with age.

Extrapyramidal signs, primitive reflexes and frontal lobe function in senile dementia of the Alzheimer type

Of 146 elderly subjects suffering from Alzheimer-type dementia, 44% were found to have significant extrapyramidal signs. Although extrapyramidal signs were more common in those who had taken neuroleptic drugs in the preceding six months, 22 subjects (15%) who were drug free also had extrapyramidal signs. Scores for cognitive function and for 'frontal lobe' signs (verbal fluency, evidence of perseveration, and primitive reflexes) were found to correlate well with scores for extrapyramidal signs, suggesting that they reflect changes in a common substratum. It is tentatively suggested that this might be an abnormality in the dopamine system.

The relationship between intellectual impairment and mood disorder in the first year after stroke

In a community-based study of patients with a first-ever stroke, intellectual impairment (as defined by scores on a common screening test for dementia, the Mini-Mental State Examination) was found in 26% at 1 month post-stroke, and in 21% at 6 and 12 month follow-up. Low scores on the screening test were associated with greater age, physical disability before the stroke, larger stroke lesion volumes as measured on CT scan, and non-stroke changes such as atrophy and white matter low attenuation on the CT scan. There was a negative correlation between scores on the Mini-Mental State Examination and symptom levels on two measures of mood disorder. However, there was no evidence of a specific relationship between major depression and low scores on the Mini-Mental State. We examined various aspects of the relationship between mood symptoms and low scores on the Mini-Mental State, but found no evidence to support the suggestion that this relationship represented an example of depressive pseudodementia. We discuss the significance of our findings for clinical psychiatry and neuropsychology.

Specificity of affective and autonomic symptoms of depression in Parkinson's disease

Previous investigators have suggested that numerous symptoms used to diagnose depression, such as sleep or appetite disturbance, are non-specific in medically ill patients, and alternative diagnostic criteria should be developed. In the study this hypothesis was tested in Parkinson's disease (PD) by comparing patients with PD who reported a depressive mood with patients having PD but without a depressive mood. Depressed patients showed a significantly higher frequency of both autonomic and affective symptoms of depression. Depressed patients with PD reported a significantly higher frequency of worrying, brooding, loss of interest, hopelessness, suicidal tendencies, social withdrawal, self-depreciation, ideas of reference, anxiety symptoms, loss of appetite, initial and middle insomnia, and loss of libido when compared with non-depressed patients. No significant between-group differences, however, were observed in the frequency of anergia, motor retardation, and early morning awakening.

Neurofibrillary changes confined to the entorhinal region and an abundance of cortical amyloid in cases of presenile and senile dementia

Cases of old-aged demented individuals exhibited abundant cortical amyloid deposits but only small numbers of neurofibrillary changes. Neuritic plaques were rare or absent. Neither Ammon's horn nor isocortex revealed sufficiently large numbers of tangles to permit the diagnosis of fully developed Alzheimer's disease. Dense accumulations of neurofibrillary tangles and neuropil threads occurred only in layer Pre-alpha (II) of the entorhinal region. This pattern of cortical destruction may represent a variant of Alzheimer's disease or an initial stage of this disorder.

Selective hypometabolism in the inferior frontal lobe in depressed patients with Parkinson's disease

Depression is a frequent finding in patients with Parkinson's disease (PD). Regional cerebral glucose metabolism was measured in depressed and nondepressed patients with PD and in age-comparable normal control subjects using 2-[18F]-fluoro-2-deoxy-D-glucose and positron emission tomography (PET). Relative metabolic activity in the caudate and orbital-inferior region of the frontal lobe was significantly lower in the depressed patients with PD as compared to both nondepressed patients and control subjects. There was a significant inverse correlation between relative glucose metabolism in the orbital-inferior area of the frontal lobe and depression scores. This study suggests that depression in PD is associated with dysfunction in the caudate and orbital-inferior area of the frontal lobe. This metabolic pattern is unlike that seen in patients with PD who have other behavioral deficits such as dementia, and suggests that disruption of basal ganglia circuits involving the inferior region of the frontal lobe may affect the regulation of mood.

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

The presence of depression and cognitive impairments was examined in seventy patients with Parkinson's disease (PD). Forty nine patients of this original cohort were re-examined between three and four years after the first evaluation. While both depressed and non-depressed patients showed a significant decline in cognitive function during the follow up period, intellectual decline was significantly more severe for the depressed group. Depressed patients also showed a faster rate of progression of motor signs (mainly tremor) than the non-depressed group. Patients that died during the follow up period showed significantly more cognitive impairments than patients who were alive at follow up. These findings suggest that either there may be two forms of PD: one with depression and rapid cognitive decline and one without depression and a gradual cognitive decline; or that the mechanisms of cognitive impairment in PD and depression may interact to produce a more rapid evolution in cognitive impairment among PD patients with a previous depression than among patients without a previous depression.

Neuroimaging and affective disorder in late life: a review

Within the past two decades brain imaging techniques have given the clinician access to new anatomical and functional findings for dealing with affective disorder in the older age group. Despite the proliferation of such technology, the significance of findings on computerized axial tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) remains unclear in this patient group. The literature covering old age depression and imaging techniques is reviewed, and problems related to methodology, sample selection, and implications for the direction of future research are discussed. Current evidence particularly suggests that subcortical atrophy may be an important factor in the genesis of affective disorder in old age. The question of cognitive decline in the setting of affective disorder is examined. The use of brain imaging techniques may have particular bearing upon identification of etiology of affective disorder, prediction of treatment response, or risk of relapse.

Coping, social support, and depressive symptoms in Parkinson's disease

Social support, depressive symptoms, and three methods of coping were assessed in 45 patients with Parkinson's disease (PD) and 24 comparably disabled controls. The PD subjects employed significantly fewer cognitive and behavioral coping strategies compared with the controls. Fewer depressive symptoms were related to increased cognitive coping in PD subjects. Behavioral coping strategies were associated with lesser depression among controls. Avoidance coping methods showed a marginally significant positive association with depressive symptoms in PD subjects. Social support was related to the significant coping predictors in each group, but was not related to depressive symptoms. Although correlational, these results might suggest that active (cognitive and behavioral) coping strategies are superior to avoidance strategies in attenuating the affective distress expected from chronic deteriorative illnesses.

The pattern of depressive symptoms varies with progression of Parkinson's disease

Whether or not depressive symptoms increase in severity with progression of Parkinson's disease (PD) remains uncertain. Unlike previous studies, we examined whether the severity of specific features of depression (mood, self reproach, vegetative, and somatic symptoms) differ with respect to the progression of PD. Results indicated that symptoms related to both mood and self-reproach were present in the early stages of PD but did not increase in severity with advancing disease. Somatic features of depression were evident early and increased with disease progression, and vegetative symptoms were seen only in the later stages of PD. The different patterns of these depressive features with progression of PD may account in part for the variations seen in previous studies.

Cortisol, ACTH, and beta-endorphin after dexamethasone administration in Parkinson's dementia

The dexamethasone suppression test (DST) has been suggested as an effective tool for differentiating between depression and dementia. After administering 1 mg dexamethasone, we measured cortisol, ACTH, and beta-endorphin levels in 32 nondepressed patients with idiopathic Parkinson's disease (PD) (14 also with dementia) and 20 healthy, age-matched controls. Four of the 20 controls, 9 of the 18 with PD alone, and 8 of the 14 with PD and dementia were dexamethasone nonsuppressors (cortisol value greater than or equal to 5 micrograms/100 ml). PD patients without dementia (nonsuppressors) showed higher basal plasma values of cortisol (22.06 +/- 5.30 micrograms/100 ml) compared with the suppressors (13.38 +/- 3.30 micrograms/100 ml). Plasma ACTH and beta-endorphin responded in a coupled way to dexamethasone challenge. Higher basal levels of both peptides were found among PD patients (demented and nondemented), nonresponders to DST. Thus, the DST does not appear to be effective in differentiating between depression and dementia in PD. In addition, PD nonsuppressors showed higher basal values of plasma ACTH, beta-endorphin, and cortisol (similar to patients with major depression). This suggests that although the depression is clinically undetectable, both disorders may share some pathophysiological features at the hypothalamic hypophyseal adrenal level.

Memory deficits in advanced Parkinson's disease

Apart from global dementia various isolated cognitive deficits have been described in Parkinson's disease (PD). We investigated 31 non-demented Parkinsonian patients in their late stages of disease and 50 control subjects with regard to verbal memory. Eleven patients suffered from an isolated verbal memory deficit as defined by two list learning tasks using the Buschke selective reminding procedure. The isolated memory impairment did not depend on depression but was associated with longer duration of PD. Twelve demented PD patients were comparable to PD patients with isolated memory impairment with regard to age at onset and duration of PD. We speculate that the isolated memory impairment in PD is associated with isolated neuronal loss in the nucleus basalis of Meynert, without cortical or limbic pathology of the Alzheimer's type.

Cognitive impairment in Parkinson's disease: amyloid plaques, neurofibrillary tangles, and neuropil threads in the cerebral cortex

Sensitive silver methods for extracellular amyloid and intraneuronal cytoskeleton abnormalities (neurofibrillary tangles and neuropil threads) were employed to examine the cortical pathology in Parkinson's disease. In cases with cognitive impairment many plaque-like amyloid deposits were found in the cerebral cortex. Neuritic plaques were rare or absent. Neither the Ammon's horn nor the isocortex revealed a sufficiently large number of tangles to permit the diagnosis of a coexisting fully developed Alzheimer's disease. Large numbers of neurofibrillary tangles and neuropil threads were only found in layer Pre-alpha of the entorhinal cortex. This layer gives rise to major portions of the perforant tract, a pathway which serves as a link in the transmission of data from isocortical association areas to the hippocampal formation. During the course of Parkinson's disease the hippocampal formation is thus endangered to become disrupted from isocortical influences. It is concluded that the cognitive impairment shown by many individuals suffering from Parkinson's disease may partly be caused by cortical lesions.

Psychiatric morbidity in patients with Parkinson's disease

Forty patients with Parkinson's disease underwent a detailed assessment of their psychiatric state using a standardized, semi-structured interview, the Present State Examination. Analysis of the interviews yielded a profile of depressive and neurotic syndromes. Comparing the results with population norms, however, revealed that the patients were distinguished only by high levels of depressed mood and loss of interest and poor concentration. In the majority of patients the range and severity of symptoms fell below the criteria for 'caseness'. Only four patients could be allocated to an ICD-9 class, two to 'neurotic depression', one to 'anxiety state' and one to 'phobic state'. This rate was almost identical to that found in the general population. Broader indices of psychiatric morbidity were related to the patients' levels of disability and cognitive function.

Depressive symptoms in Parkinson's disease: a comparison with disabled control subjects

A high incidence of depressive symptoms has been observed in patients with Parkinson's disease (PD). PD involves a loss of central monoamines, and a decrease of monoamines has been implicated in depression; therefore, it is possible that depressive symptoms in PD result from the loss of endogenous neurotransmitters. However, it is equally possible that depressive symptoms represent a reaction to the chronic disabling course of PD. By comparing depressive symptoms in PD patients to those in matched patients with other chronic disabling diseases not involving a loss of central monoamines, it may be possible to decide between these alternatives. Thus, depressive symptoms were assessed in 45 patients with PD and 24 disabled controls that did not differ from the PD subjects on a measure of functional disability. Results showed that PD subjects obtained significantly higher total scores on the Beck Depression Inventory (BDI) than controls. PD subjects scored significantly higher than controls on BDI items grouped to reflect cognitive-affective and somatic depressive symptoms. The BDI scores of PD subjects were not reliably related to age, sex, duration of PD, or clinical ratings of PD symptom severity or functional disability. Self-rated disability and the number of recent medical problems were the greatest predictors of depressive symptoms. These findings supported the hypothesis that depressive symptoms in PD may not represent solely a reaction to disability.

Depressive syndromes in schizophrenic patients after discharge from hospital. ANI Study Group Berlin, Düsseldorf, Göttingen, Munich

A total of 364 schizophrenic outpatients who were stabilized for 3 months on continuous neuroleptic therapy after discharge from the hospital were rated according to three different scales for depressive syndromes (Brief Psychiatric Rating Scale anxious depression factor, AMDP/depression, and the self-rating PD-S depression scale). Between 19.5% and 27.5% of the patients were rated as depressed, or 35.7%-42.8%, when mild depressive syndromes were included. There were low, but significant correlations between demographic or life-event data and depression scores on the self-rating scale, whereas fewer correlations were found on the observer ratings. No associations were found between social adjustment and depression. Moderate correlations were found between measures of the apathetic syndrome and depression ratings, while observer ratings showed higher correlations than the self-rating. High depression scores, especially in the observer ratings, correlated with scales for global psychopathological assessment (CGI, GAS). There were significant correlations between extrapyramidal rigidity and observer rating depression scores, whereas the total amount of neuroleptics given had no influence. These results are interpreted on the basis of hypotheses about depressive syndromes in schizophrenia.

Dexamethasone suppression test in patients with Parkinson's disease

The Dexamethasone Suppression Test (DST), supposed to effectively distinguish between endogenous and nonendogenous depression, was performed in a group of 34 patients with Parkinson's disease. Abnormal DST results were observed in 50% of the patients. The patients were clinically divided into subgroups of depressed and nondepressed parkinsonians. Abnormal DST results were significantly more frequent in depressed (75%) than in nondepressed parkinsonians (27.7%).

Organic disorders of personality

Organic illnesses may produce alterations in behavior that closely resemble personality disorders. Careful differential diagnosis is necessary in formulating appropriate treatment.

A controlled trial of piracetam in intellectually impaired patients with Parkinson's disease

Twenty patients with Parkinson's disease and marked intellectual impairment or dementia participated in a double-blind placebo controlled trial of the nootropic, piracetam. A standardized neurological examination, a neuropsychological test battery, and a functional scale, The Sickness Impact Profile, were completed for all patients. They were then assigned by blind randomization to drug or placebo conditions receiving 3.2 g of piracetam or an identical amount of placebo for 12 weeks. The dose was increased to 4.8 g for an additional 12 weeks. Neurological, psychological, and functional measures were rated as improved, unchanged, or worsened in comparison to baseline performance. Twenty-five percent of the patients did not complete the trial for reasons unrelated to the medication. Although there was a significant improvement on one subtest of the functional scale, no significant effects were demonstrated in cognitive or neurological measures.

Parkinson's disease: a conceptualization of neuropsychological deficits within an information-processing framework

Parkinson's disease patients are frequently impaired in a variety of neuropsychological tasks involving memory, perceptual motor performance and cognitive flexibility. Although various theories have been forwarded to explain specific impairments, few attempts have been made to account for all the deficits within a single theoretical framework. Furthermore, the frequent occurrence of dementia, the adverse side effects of medication and the motor symptoms of the disease tend to interfere with neuropsychological performance. This has hindered the clear delineation of the neuropsychological profile of Parkinsonian patients. The present paper examines the evidence for intellectual deficits in non-demented Parkinson's disease patients. A number of problems inherent in cognitive research on Parkinson's disease are discussed. The contribution of dementia, motor symptom severity and medication in the expression of these intellectual impairments is examined. It is suggested that many of the neuropsychological deficits described in Parkinson's disease may result from a common underlying deficit in some aspect of information processing. Although it is not possible to pinpoint the precise mechanism(s) involved on the basis of the available evidence, several possibilities are suggested by cognitive and electrophysiological data.

Reduced rapid eye movement sleep latency in patients with Parkinson's disease

Rapid eye movement (REM) sleep latency (time from sleep onset to the first REM episode) was measured in 39 patients with idiopathic Parkinson's disease. Reduced REM sleep latency (less than or equal to 65.0 min) was found in a high proportion of patients (69%). Since reduced REM sleep latency may be a trait-like abnormality relatively specific to primary depression, we evaluated this parameter in two groups of parkinsonian patients: depressed (16 patients) and non-depressed (23 patients). Its incidence was significantly higher in depressed patients with Parkinson's disease.

Depression type in Parkinson disease

Thirty-three patients with Parkinson Disease were evaluated neurologically and neuropsychologically. Seventy percent without a previous psychiatric diagnosis, were depressed. This depression was not related to the presence of dementia, stage of the disease, a general estimate of memory and attention, years of Parkinsonism, age, or indices of frontal cortex-related functioning. Because the depression did not positively relate to factors suggestive of advancing disease, it is proposed that the depression is reactive to the disease rather than an integral part of it.

Neuropsychological similarities in lateralized parkinsonism

Parkinson's disease (PD) patients who have left or right predominance of motor symptoms may exhibit cognitive differences. Previous research found greater neuropsychological impairment in patients with both right and left motor predominance, and some found no differences. Variability in overall severity of disease among the patients studied makes evaluation of these reports difficult. We examined the possibility that neuropsychological differences may occur in different stages of disease by comparing patients with mild unilateral disease (Exp. 1) and advanced disease (Exp. 2). Results indicated that while overall cognitive impairment increased with advancing disease, the pattern of neuropsychological impairments were not different with respect to laterality of motor symptoms in either experiment.

Major depression in Parkinson's disease and the mood response to intravenous methylphenidate: possible role of the "hedonic" dopamine synapse

The euphoric response to equivalent doses of intravenous methylphenidate (MTP) was assessed in a group of 13 Parkinsonian patients affected by major depression, in a group of 11 nondepressed Parkinsonians, in a group of 14 nonparkinsonian subjects suffering from major depression, and finally in a group of 12 controls with no CNS or psychiatric disease. Subjects of all four groups were matched for age, sex and other main characteristics. Depressed and nondepressed Parkinsonians were also matched for duration and severity of illness, and for the type of antiparkinsonian treatment. The response to MTP was evaluated in the context of a double-blind, placebo-controlled study. Parkinsonian patients with major depression exhibited a significant lack of sensitivity to the euphoriant effects of MTP, in comparison with the other three groups. Euphoria produced by central stimulants has been shown to depend on the activity of a dopamine synapse in humans, which is thought to be situated at the limbic terminals of dopamine neurons located in the ventral tegmental area. Degeneration of this system may have predisposed our Parkinsonian patients to major depression.