Platelet MAO activity in geriatric patients with depression and dementia

The authors studied platelet MAO activity in psychiatrically hospitalized geriatric patients with depression and dementia. Platelet MAO activity was higher in demented patients with and without depression and in depressed patients with reversible dementia than in nondemented depressed patients. The data suggest that abnormally high platelet MAO activity may reflect a predisposition to the development of a dementia syndrome.     

Lymphopenia in primary degenerative dementia

The central nervous and immune systems share a number of common properties, e.g. neurotransmitter receptors. In contrast to age matched healthy and/or hypertensive controls, the total lymphocyte count in 25 carefully diagnosed and staged patients with primary degenerative dementia were significantly reduced and also correlated with the severity of their dementia. Subjects' age, age of dementia onset, or duration of illness were unrelated. Total leukocyte counts were similar between groups. Nutritional status, ACTH, or plasma cortisol in dementia cohort were also not explanatory of their lymphopenia. These results are potentially significant in light of an immune hypothesis for primary degenerative dementia: Alzheimer's type and/or that population's high concomitant risk of infection.     

Platelet MAO activity in posttraumatic stress disorder

Platelet monoamine oxidase (MAO) activity was assessed in 23 patients with posttraumatic stress disorder and 19 age-matched male control subjects. An overall significantly lower MAO activity was observed in the posttraumatic stress disorder group. When the group was divided into those with and those without a history of alcohol abuse, only the former group differed significantly from control subjects. The heuristic importance of these findings is discussed.     

Platelet MAO activity and personality characteristics

Low levels of platelet monoamine oxidase have been found in schizophrenic and bipolar depressive patients. The enzyme activity seems to correlate negatively with certain personality traits (social activity, sensation seeking, hypomania, positive affect and monotony avoidance) which are correlated to some extent with the score “extraversion” from the Eysenck Personality Questionnaire (EPQ). The present study was carried out in an attempt to investigate further the possible correlation between platelet MAO activity and the personality traits measured by the EPQ. 41 schizophrenic patients and 20 healthy probands were blindly examined for platelet MAO activity and personality characteristics. The enzyme activity was found to correlate negatively with the extra-version score in patients and healthy probands, which is in agreement with the data from other studies. This correlation is discussed and a hypothesis suggested.     

Platelet MAO activity and personality variations in normals

The authors examined platelet MAO activity and several personality variables in 58 non-clinic-referred healthy adult males. The psychological tests administered consisted of the Minnesota Multiphasic Personality Inventory, the Personality Research Form-E, and the Zuckerman Sensation Seeking Scale. The findings replicated previous findings in the literature.     

Topographic maps of brain electrical activity in primary degenerative dementia of the Alzheimer type and multiinfarct dementia

The topography of the electroencephalographic (EEG) pattern of ten patients with primary degenerative dementia of the Alzheimer type, ten multiinfarct dementia patients, and ten age-matched controls was compared during three different behavioral conditions: resting condition with eyes open (EO), memorizing a list of words (M), and recalling the same list of words (R). Results indicate that the alpha frequency band does not show significant changes. On the other hand, the theta band could be considered an important factor in the differential diagnosis of the primary degenerative dementia of the Alzheimer type, showing a higher power over right posterior regions in this group of patients compared with the multiinfarct dementia patients under different behavioral conditions.     

Oxiracetam in the treatment of multi-infarct dementia and primary degenerative dementia

Oxiracetam is a recently synthesized nootropic that was tested as a potential treatment for cognitive decline in patients with multi-infarct dementia (MID) and primary degenerative dementia (PDD). Subjects were 34 MID patients and 39 PDD patients who met entrance criteria for the study. A repeated measures ANOVA showed significant improvement in both patients with MID and patients with PDD for word fluency. The total score on the Relatives' Assessment of Global Symptomatology-Elderly showed significant improvement for patients with PDD. The average score on the Instrumental Activities of Daily Living Scale, however, showed a significant decline for patients with PDD.     

Platelet MAO activity and psychosis proneness in college students

A population of individuals potentially at risk for psychiatric disorders was identified by screening 633 college students using the Wisconsin Scales for psychosis proneness. Platelet monoamine oxidase (MAO) activity was measured in high-scoring individuals and controls using 14C-benzylamine. Males with deviant scores on the Perceptual Aberration-Magical Ideation Scale showed a bimodal distribution of platelet MAO activity. Kinetic analysis of platelets from probands with the highest and lowest levels of MAO activity in this group revealed differences in Vmax but not in Km. Since abnormal platelet MAO activity has been linked to psychiatric vulnerability, the results provide further support for the validity of the Wisconsin Scales as predictors of psychopathology.     

Platelet MAO activity and family history of schizophrenia

Platelet monoamine oxidase (MAO) activity was studied in 50 drug-free schizophrenics divided into groups according to whether they had at least two first-degree relatives with schizophrenia (n=6), only one first-degree relative with schizophrenia (n=8), or no family history of schizophrenia (n=36). Similar determination was made in 56 age-matched normals. There were no differences in the platelet MAO activity between any of the groups of schizophrenics or the normals. The results are discussed in light of previous studies of platelet MAO activity in schizophrenics with and without a family history of schizophrenia.     

Mitochondrial function in brain tissue in primary degenerative dementia

Previous in vitro and in vivo studies of the brain in Alzheimer's disease indicated alterations in metabolism related to energy production although the relationships between these changes remains obscure. To help resolve this issue, in vitro oxygen uptake by homogenates of fresh samples of frontal neocortex from patients with dementia and neurosurgical controls has been examined as a measure of energy-related metabolism and mitochondrial function. Maximal respiratory rates (measured in the presence of an uncoupling agent) were similar for samples from 7 controls, 5 patients with Alzheimer's disease and two patients diagnosed clinically as Pick's disease, suggesting that there was little or no effect of these dementias on the maximal metabolic capacity of the tissue. However, under some conditions producing sub-maximal metabolic activity (which are of potentially greater physiological relevance) oxygen uptake rates were significantly elevated in the dementia group. The ratio of oxygen uptake rates in the presence and absence of ADP was significantly reduced (to 58% of control; P less than 0.02) for the dementia patients compared with controls, possibly indicative of partial mitochondrial uncoupling. These results indicate metabolic changes expressed in vitro which may be relevant to the pathogenesis of Alzheimer's disease and some related dementias.     

Hydergine treatment and psychophysiological measures in primary degenerative dementia

Changes in smooth pursuit eye movements and the P300 component of the auditory evoked potential were studied in patients with primary degenerative dementia during a double-blind, placebo-controlled study of ergoloid mesylates (Hydergine). After 18 weeks of treatment, P300 latency and amplitude, recorded at three scalp electrode sites, had not changed significantly. Smooth pursuit gain was elevated for the drug group under some stimulus conditions, suggesting a normalization of pursuit eye movement functioning. However, the results of several other measures of the quality of pursuit eye movements failed to corroborate this finding.     

Fingerprint pattern differences in early- and late-onset primary degenerative dementia

The frequency distribution of major fingerprint patterns (ulnar or radial loops, arches, and whorls) was studied in 47 men with early-onset (aged, less than or equal to 64 years), 35 men with late-onset primary degenerative dementia (aged, greater than or equal to 65 years), and 100 control subjects (aged, 29 to 78 years). Patients with an early, but not those with a late, onset of dementia had significantly more ulnar loops than the control group. This finding, along with other data, is interpreted as indicating that there may be a biologic basis for distinguishing these two forms of dementia.     

DSM-III-R criteria for primary degenerative dementia and multi-infarct dementia [corrected]

Primary degenerative dementia (PDD) and multi-infarct dementia (MID) are the two most common categories of cognitive decline in old age. The definitions of these two clinical entities are currently based on clinical evaluation and on the exclusion of other underlying causes, and still lack a consensus. The DSM-III-R criteria are widely used for the diagnosis of dementia. However, their role in the differentiation between PDD and MID has not been thoroughly examined. A consecutive series of 98 demented patients who met the DSM-III-R criteria for dementia were admitted to a clinical study. Upon evaluating their type of dementia according to these criteria, 53 patients could not be diagnosed either as having PDD or MID. The DSM-III-R criteria for these two types of dementia are critically reviewed. Proposed modifications, aimed at refining their differential diagnostic role, are presented, enabling better allocation of demented patients into PDD, MID, or intermediate groups.     

Platelet MAO activity and the dexamethasone suppression test in bipolar depression

The correlation between postdexamethasone cortisol levels after the dexamethasone suppression test (DST) and platelet monoamine oxidase (MAO) activity was studied in 31 depressed female inpatients with Research Diagnostic Criteria primary, endogenous, bipolar depression (12 bipolar 1 and 19 bipolar 11). Out of the 31 patients, 25 showed abnormal DST results. Platelet MAO activity did not differ significantly from the matched control group. There was a trend that patients with higher MAO activity had lower postdexamethasone cortisol levels, but it was significant only for the 0800 hr cortisol levels.     

Platelet MAO activity and the dexamethasone suppression test in depressed patients

Platelet monoamine oxidase (MAO) activity and postdexamethasone cortisol levels were determined in 26 depressed patients. The incidence of cortisol nonsuppression and the mean postdexamethasone cortisol levels were significantly higher in patients with high MAO activity than in those with low MAO activity.     

Platelet MAO activity and long-term outcome in schizophrenia and schizoaffective disorder

Several years after MAO activity determination, 36 patients with schizophrenia or schizoaffective disorder were contacted for assessment of their outcome. Patients who had had low platelet MAO activity had significantly better social adjustment and fewer schizophrenic symptoms at follow-up.