Robert S. Marin

Computerized EEG spectral analysis in elderly normal, demented and depressed subjects

Computerized spectral analysis of the EEG was performed in 35 patients with Alzheimers disease and compared to patients with major depression (23) and healthy elderly controls (61). Compared to controls, demented patients had a significant increase in the theta and alpha 1 bandwidths as well as an increased theta-beta difference. The parasagittal mean frequency, beta 1 and beta 2 activity were significantly decreased. Depressed patients differed from demented patients, particularly at the lower end of the spectrum, having significantly less delta and theta activity. Like the demented group, depressed patients also had a decreased parasagittal mean frequency, beta 1 and beta 2 when compared to controls. In demented patients, there was a high correlation between several spectral parameters (parasagittal mean frequency, delta and theta activity, and the theta-beta difference) and the Folstein score, EEG measures used for discriminant analysis were more accurate in identifying demented patients who had lower Folstein scores.

The sources of convergence between measures of apathy and depression

Apathy and depression are discriminable but related dimensions of behavior. The purpose of this study was to evaluate the source of the overlap between measures of apathy and depression. We evaluated the intercorrelations between the Apathy Evaluation Scale (AES) and the Hamilton Rating Scale for Depression (HamD) in 107 subjects, aged 53-85, who met research criteria for normal aging, left or right cerebral hemisphere stroke, probable Alzheimers disease, or major depression. We determined the correlation between the individual items on the HamD and the total scores on the AES and the HamD. The HamD items having the strongest correlations with AES total score were diminished work/interest, psychomotor retardation, anergy, and lack of insight. The correlation between AES and HamD total scores was nonsignificant when major depression subjects and these variables most closely related to apathy were excluded from consideration. These findings indicate that the convergence between HamD and AES is attributable to (i) a subset of HamD items which are consistent with the syndrome of apathy and (ii) the fact that major depression is associated with both apathy and depression. Clinical and research applications of these results are discussed.

EEG sleep in elderly depressed, demented, and healthy subjects

In a prospective study of EEG sleep patterns in 25 elderly depressives, 25 elderly demented patients, and 25 healthy, elderly control subjects, the sleep of depressives was characterized by reduced REM sleep latency, increased REM percent and first REM period density, and altered temporal distribution of REM sleep, as well as by diminished sleep maintenance (correlated significantly with Hamilton ratings of depression: multiple R = -0.42, p less than 0.05). In contrast, the sleep of demented patients showed reduced REM sleep percent, but normal REM temporal distribution, increased loss of spindles and K-complexes (the latter correlating significantly with severity of cognitive impairment as measured by the Folstein score: multiple R = -0.59, p less than 0.01), and less severe sleep maintenance difficulty than for depressives. An examination of REM latency demonstrated a skewed distribution in depression (i.e., 42% of nights with sleep-onset REM periods), but a normal distribution in the controls and demented subjects. A REM latency cut-off score of 30 min correctly classified 68% of all patients (kappa = 0.36; p less than 0.005), compared with 78% correctly identified in our retrospective study (Reynolds et al. 1983).

Apathy: Concept, Syndrome, Neural Mechanisms, and Treatment.

The essential meaning of apathy is lack of motivation. Criteria for diagnosing the syndrome of apathy and for distinguishing symptomatic and syndromal apathetic states are based on this definition, whereas assessment of apathy as a continuous variable is operationalized in the Apathy Evaluation Scale, which provides reliable and valid measures of diminished motivation in diverse clinical populations. The clinical utility of this formulation is shown by describing the causes, differential diagnosis, and treatment of apathy. The neural mechanisms of apathy are postulated to involve the brainstem and forebrain circuits that mediate goal-directed behavior. The functions of these circuits provide a model for understanding a provisional classification of apathy syndromes into cognitive, sensory, motor, and affective subtypes. This classification and its postulated neural basis has heuristic value for increasing our understanding of the disorders in which apathy is prominent.

Disorders of diminished motivation.

Disorders of diminished motivation occur frequently in individuals with traumatic brain injury. Motivation is an ever-present, essential determinant of behavior and adaptation. The major syndromes of diminished motivation are apathy, abulia, and akinetic mutism. Depending on their etiology, disorders of diminished motivation may be a primary clinical disturbance, a symptom of another disorder, or a coexisting second disorder. This article presents a biopsychosocial approach to the assessment and management of motivational impairments in patients with traumatic brain injury. The recognition and differential diagnosis of disorders of diminished motivation, as well as the mechanism and clinical pathogenesis, are discussed.

Control-Relevant Intervention in the Treatment of Minor and Major Depression in a Long-Term Care Facility

The authors assessed the effect of a control-relevant psychosocial intervention in 31 nursing home residents with either major depressive episode or minor depression. An initial group of 22 residents were randomized to either active treatment or waiting list. Four of 11 residents randomized to active treatment were deemed Responders, compared with 0 of 11 on the waiting list (P < 0.05). Of the total of 31 residents who participated in the intervention, 14 (45%) were deemed Responders during the intervention period. For these Responders, the Hamilton Rating Scale for Depression (Ham-D) and Geriatric Depression Scale scores improved significantly during the intervention. The improvement in the Ham-D was not sustained 2 months after intervention was terminated. These findings suggest that a psychosocial intervention enhancing socialization according to each residents choice had a positive therapeutic impact on almost half of the nursing home residents with major or minor depression. However this effect could not be sustained by the residents without the support of the structured program.

Apathy and Executive Function in Depressed Elderly

Apathy and executive cognitive dysfunction (ECD) are important though conceptually different aspects of late-life depression. The primary objective of this study was to evaluate the relationship of apathy to ECD. The authors also evaluated the relationship of apathy and ECD to global cognitive impairment and word generation. Fifty-two elderly subjects with major depression and MMSE scores of 15 or greater were evaluated with apathy-related items from the Hamilton rating scale for depression (ApHRSD), the Executive Interview (EXIT), the Dementia Rating Scale (DRS), and the Controlled Oral Word Association test (COWA). ApHRSD scores were not significantly correlated with any of these variables. EXIT scores were correlated significantly with DRS and COWA. The results suggest that apathy and ECD may be independent of each other in some samples of elderly with late-life depression. Correlations may have been reduced by low variance for the variables of interest and by psychometric limitations of the ApHRSD. (J Geriatr Psychiatry Neurol 2003; 16:112-116)

Elevated red blood cell/plasma choline ratio in dimentia of the Alzheimer type: Clinical and polysomnographic correlates

In a prospective study we have observed a shift in distribution of red blood cell (RBC)/plasma choline ratios among patients with probable dementia of the Alzheimer type (DAT), compared with healthy controls and depressed patients. Fifteen of 22 DAT patients (68%) showed RBC/plasma choline ratios greater than 1.9, in contrast to 9 of 26 healthy controls (35%) and 7 of 20 depressives (35%). These significant differences confirm and expand earlier observations. The subgroup of DAT patients with elevated RBC/plasma choline ratios is older and more cognitively impaired, shows later onset of dementia, and has less rapid eye movement (REM) sleep than the DAT subgroup with normal RBC/plasma choline ratios. Within the entire group of DAT patients, moreover, the RBC/plasma choline ratio shows a significant inverse correlation with REM sleep latency. These findings are discussed in relation to abnormalities in other nonneural Alzheimer tissues and within the context of cholinergic involvement in both DAT and the timing of REM sleep.

Apathy After Hip Fracture: A Potential Target for Intervention to Improve Functional Outcomes

The authors examined apathy symptoms, their improvement, and their association with functional recovery after a hip fracture. Of 126 participants, 37% had clinically significant apathy symptoms, which predicted functional outcome (i.e., poorer recovery from the fracture among those with higher baseline apathy). Of participants with high baseline apathy, approximately one-third improved; these participants had a better functional outcome than those with persistently high apathy scores. It is concluded that apathy symptoms are common after a hip fracture, but improve in one-third of individuals, with a concomitant functional recovery after hip surgery. Interventions to prevent or improve apathy in elderly persons deserve further attention.

Psychometric characteristics of the Children's Motivation Scale.

A 16-item Childrens Motivation Scale (CMS) was developed to evaluate level of motivation in children and adolescents. The study population consisted of a normative sample of 290 school children and a clinical sample of 165 child and adolescent psychiatric patients. Test-retest, internal consistency, and interrater reliability were fair to good for both samples. Validity of the CMS was demonstrated by its ability to differentiate clinical from normative samples according to the level of motivation, by a significant correlation of the CMS with an independent measure of withdrawal, and by its lack of correlation with an independent measure of depression. Principal components analysis identified a three-component structure. These findings support the conclusion that the CMS accesses a clinically important but often overlooked psychiatric construct.