Biomedical subjects

M A Butters

Publications and source records attributed to M A Butters.

16 recordsLinked to original sources

PubMed2001

Endogenous concentrations of DHEA and DHEA-S decrease with remission of depression in older adults.

BACKGROUND: Clinical studies of endogenous concentrations of dehydroepiandrosterone (DHEA) and its sulfated conjugate DHEA-S in depression are limited. This study was designed to evaluate the influence of successful pharmacological treatment of late-life depression on concentrations of DHEA, DHEA-S and cortisol. METHODS: We determined endogenous concentrations of DHEA, DHEA-S and cortisol in elderly control subjects (n = 16) and in elderly depressed patients who remitted (n = 44) or failed to remit (n = 16) with pharmacological treatment. Depressed patients were treated for 12 weeks with either nortriptyline or paroxetine. RESULTS: In remitters, DHEA and DHEA-S concentrations were lower at week 12 than at week 0 (p =.002 and p =.0001, respectively). In the nonremitters and control subjects, neither DHEA nor DHEA-S concentrations changed. Decreases in hormone concentrations were associated with improvement in mood and functioning in depressed patients. Although cortisol concentrations decreased in remitters and nonremitters, the change was not significant. CONCLUSIONS: Our data suggest that the decrease in DHEA and DHEA-S in remitters is related to remission of depression rather than to a direct drug effect on steroids, as nonremitters had no change in hormone concentrations.

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PubMed2001

Dual-task performance in depressed geriatric patients.

Older patients suffering from a major depression are often impaired on tasks that require executive control processes. However, a wide variety of executive abilities exist in humans, and it is not clear that all are impaired in depression or that such impairments persist beyond remission of the depression. One executive process that plays a central role in mental operations such as working memory is the ability to co-ordinate the simultaneous performance of multiple tasks. Dual-task performance has been extensively studied in normal subjects but there is little work with depressed patients. The present study examined the performance of depressed (M age=71.0, S.D.=7.1) and control subjects (M age=69.3, S.D.=7.0) on two tasks (visual tracking and backward digit span), both when each task was carried out by itself and when the two tasks were carried out simultaneously. Dual-task performance was impaired in depressed patients prior to antidepressant treatment and this impairment persisted even after remission of the depression. These results suggest that, like other executive abilities, the ability to schedule and co-ordinate the conflicting processing demands present in a dual-task situation is impaired in depressed geriatric patients and that this impairment may be a trait effect.

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PubMed2001

Rehabilitation of the geriatric vascular amputee patient: a population-based study.

OBJECTIVES: To determine the rate of successful prosthetic fitting in geriatric vascular amputees in the community and to determine predictors of successful fit. DESIGN: Epidemiologic survey. SETTING: General community, Olmsted County, Minnesota. PATIENTS: All Olmsted County residents more than 65 years old who had a major lower extremity amputation (below knee amputation [BKA] or higher) for peripheral vascular disease between 1974-1995, of whom 199 were identified. Median age at amputation was 79.7 years with a median survival of 1.5 years. INTERVENTION: A retrospective chart review. MAIN OUTCOME MEASURE: Successful prosthetic fit. RESULTS: Amputation levels were: 64% BKA, 4.5% knee disarticulation, 31% above knee amputation (AKA), and 0.5% hip disarticulation. Only 36% of the population was successfully fitted, compared with 74% of patients referred to the Amputee Clinic. Major reasons for not being fitted included death, reamputation, cerebrovascular disease, and cognitive deficits. Increased age (p < .001), cerebrovascular disease (p < .001), dementia (p = .002), and AKA (p < .001) were associated with failure to fit. CONCLUSION: The high probability of successful prosthetic fitting reported among referral practices cannot be generalized to unselected elderly individuals. However, selected individuals can successfully be fitted with a prosthesis; knowledge of predictors of prosthetic fitting may facilitate setting of realistic goals during presurgical counseling in this age group.

Age Factors↗

PubMed2001

Alcohol dementia: "cortical" or "subcortical" dementia?

Most dementias are considered to exhibit either a predominantly "cortical" (e.g. Alzheimer's disease, AD) or "subcortical" (e.g. Parkinson's disease) pattern. A double dissociation has been reported, such that cortical and subcortical dementias can be differentiated based on performance on tests of declarative and procedural learning. The goal of this study was to determine if subjects with alcohol dementia exhibit a predominantly cortical or subcortical dementia profile. The performance of 10 elderly subjects diagnosed with alcohol dementia, 29 elderly subjects with histories of alcohol dependence but who were not demented, and 11 subjects with AD was compared to 20 elderly control subjects. The results indicated that the procedural learning task did not differentiate among the groups, whereas the discriminability index from the California Learning Test (the declarative learning task) did. Thus, alcohol dementia cannot clearly be ascribed to either dementia classification.

Journal Article↗

PubMed2000

Effects of estradiol and progesterone administration on human serotonin 2A receptor binding: a PET study.

BACKGROUND: Preclinical studies demonstrate that 17beta-estradiol (E(2)) increases serotonin-2A receptor (5-HT(2A)R) density in rat frontal cortex. METHODS: We investigated the impact of hormone replacement therapy on 5-HT(2A)R binding potential (BP) using positron emission tomography and [(18)F]altanserin in five postmenopausal women. Subjects were imaged at baseline, following 8 to 14 weeks of transdermal E(2), 0.1 mg/d, and following 2 to 6 weeks of E(2) plus micronized progesterone (P) 100 mg per os twice daily. Regional BPs in the anterior cingulate cortex, dorsolateral prefrontal cortex, and lateral orbitofrontal cortex were calculated by Logan analysis. RESULTS: There was a main effect of time (p = .017) for 5-HT(2A)R BP, which increased 21.2%+/-2.6% following combined E(2) and P administration relative to baseline. This effect was evident in all cerebral cortex regions examined. CONCLUSIONS: 5-HT(2A)R BP increased in widespread areas of the cerebral cortex following combined E(2) + P administration.

Binding, Competitive↗

PubMed2000

Decreased working memory and processing speed mediate cognitive impairment in geriatric depression.

BACKGROUND: While neuropsychological dysfunction is common in geriatric depression, not all aspects of cognition are equally affected. It has been suggested that depressed patients are impaired only in tasks that make heavy demands on processing resources and that a resource decrement therefore underlies the neuropsychological decrements seen in geriatric depression. The present study examined whether processing resources in the form of working memory and information processing speed are decreased in depression and whether a decrease in these resources actually mediates neuropsychological impairment. METHODS: Measures of processing resources were administered to elderly depressed patients prior to treatment and to age-matched controls. Patients whose depression remitted were retested as were the controls. Subjects also received neuropsychological tests of episodic memory and visuospatial performance. RESULTS: Depressed patients performed significantly worse on measures of both processing speed and working memory. While performance on these measures improved in patients whose depression remitted, the amount of improvement was no greater than that seen in the controls with repeat testing. Hierarchical regression analyses showed that depression explained a significant amount of variance on the neuropsychological tasks. However, if the variance associated with processing resources was removed first, depression no longer accounted for a significant amount of neuropsychological variance. CONCLUSIONS: Processing resources are decreased in elderly depressed patients and this decrease in resources appears to mediate impairments in several areas of neuropsychological functioning including episodic memory and visuospatial performance. The resource decrement persists after remission of the depression and thus may be a trait marker of geriatric depression.

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PubMed2000

Changes in cognitive functioning following treatment of late-life depression.

OBJECTIVE: Knowledge of the relationship between various clinical characteristics and cognitive functioning is advancing, but little is known about the cognitive response to treatment for geriatric depression. The purpose of this study was to examine the cognitive response to treatment for patients with late-life depression. METHOD: Subjects included 45 nondemented, elderly depressed patients who achieved remission after 12 weeks of antidepressant treatment and 20 elderly comparison subjects. All subjects were administered a battery of clinical measures, including cognitive screening instruments, before and after treatment. RESULTS: As a group, the elderly depressed patients showed a small improvement in overall cognitive functioning after treatment. Among depressed patients with concomitant cognitive impairment at baseline, performance on the Mattis Dementia Rating Scale domains of conceptualization and initiation/perseveration improved significantly relative to those of depressed patients with normal cognition. Despite the improvement following treatment, the overall level of cognitive functioning in the elderly depressed patients with cognitive impairment at baseline remained mildly impaired, especially in the memory and initiation/perseveration domains. CONCLUSIONS: Elderly depressed patients with cognitive impairment may experience improvement in specific domains following antidepressant treatment but may not necessarily reach normal levels of performance, particularly in memory and executive functions. This subgroup of late-life depression patients is likely at high risk of developing progressive dementia.

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PubMed2000

Alcohol, dementia, and Alzheimer's disease: comparison of neuropsychological profiles.

Thirty-nine detoxified elderly alcoholics (mean age = 65.85) completed a comprehensive assessment designed to identify individuals meeting DSM-IV criteria for alcohol-related dementia. Ten subjects meeting criteria (mean age = 69.8; mean Mini-Mental State Examination [MMSE] = 25.1) were compared to the 29 nondemented alcoholics (mean age = 64.5; mean MMSE = 27.8), 9 patients with Alzheimer's disease (mean age = 73.4; mean MMSE = 22.3), and 15 control subjects (mean age = 70.8; mean MMSE = 28). Comparison of neuropsychological test scores revealed several statistically significant differences. Furthermore, the overall pattern of test performance between the two demented groups was different. Alzheimer's patients were more impaired on confrontation naming, recognition memory, animal fluency, and orientation. Alcohol dementia subjects were more impaired than controls on initial letter fluency, fine motor control, and free recall. However, alcohol dementia subjects did not differ from controls on tests of verbal recognition memory. This study suggests that it is possible to clinically differentiate the cognitive deficits of alcohol-related dementia from typical Alzheimer's disease. However, the results are preliminary and are based on small sample sizes so should be interpreted with caution.

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PubMed2000

The neuropsychological consequences of abstinence among older alcoholics: a cross-sectional study.

BACKGROUND: The older alcoholic has been distinguished from the younger alcoholic with regard to both the acute effects of alcohol and also the recovery of functioning with abstinence. Few studies, however, have included samples of exclusively older subjects. In this investigation we examined the recovery of functioning in an older cohort of recovering alcoholics (age range 55-83) to determine which neuropsychological functions improve and which remain impaired with abstinence. METHODS: We used a cross-sectional design, comparing three demographically matched groups on a battery of neuropsychological tests: (a) older alcoholics who had been abstinent for greater than 6 months, (b) older alcoholics who had been abstinent for less than 6 months, and (c) a control group of older subjects without alcohol abuse histories. RESULTS: In almost all tasks, the alcoholics who were abstinent for less than 6 months performed worse than the control group. In contrast, the alcoholics who had been abstinent for more than 6 months differed from the control group on learning and recall of a word list, immediate and delayed recall of a complex figure, initial letter fluency, and clock drawing. CONCLUSIONS: Memory and executive skills appear to be resistant to recovery or at least slower to recover with abstinence in the older alcoholic. The impairment with visuospatial skills reported in prior investigations of alcoholics may be related to compromised executive functions, which interfere with the encoding of more complex visuospatial information and thus affect recall of such information. Studies that involve larger samples of older alcoholics are needed to understand their ability to recover cognitive functioning with abstinence.

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PubMed1999

Cognitive effects of paroxetine in older depressed patients.

This study examined whether paroxetine produces cognitive toxicity in elderly patients suffering from a major depressive episode. Twenty-nine depressed patients with a wide range of cognitive functioning were treated with paroxetine. At baseline and during 6 weeks of treatment, patients were asked to complete various measures of cognitive function and had blood drawn to determine serum anticholinergicity. Measures of attention and cognitive speed showed significant improvement with treatment, while the memory performance remained unchanged. A similar pattern of results was found in both cognitively impaired and intact patients. The slight increase in serum anticholinergicity seen in some elderly patients did not significantly impair cognitive function, even in patients with a preexisting cognitive impairment.

Age Factors↗

PubMed1998

Neuropsychological similarities and differences among Huntington's disease, multiple sclerosis, and cortical dementia.

A comparison of cognitive function was made among patients with Huntington's disease, multiple sclerosis, and cortical dementia. Utilizing indexes from the Wechsler Adult Intelligence Scale and the Halstead-Reitan Battery, it was found that there was substantially more severe cognitive deficit in the Huntington's disease patients than in the multiple sclerosis patients, and the level of impairment was similar between the Huntington's disease and cortical dementia groups. Qualitative differences, particularly involving amount and type of perseveration, were noted among the three groups. It was concluded that subcortical dementia is not necessarily characterized by mild cognitive impairment, and there appear to be important qualitative differences between cortical and subcortical dementia. Results are discussed in terms of the usefulness of the presently conceptualized distinction between cortical and subcortical dementia.

Journal Article↗

PubMed1996

Focal temporal lobe dysfunction in probable Alzheimer's disease predicts a slow rate of cognitive decline.

The memory disorder in Alzheimer's disease (AD) can be described as having two components: one primarily a defect in secondary memory and the other a defect in executive processes. We compared and contrasted the pattern of neuropsychological impairment in AD patients as a function of their memory and executive deficits. A K-Means cluster analysis identified four groups of patients. All four groups had impaired episodic and semantic memory and three had progressively more severe impairments in executive functions. The fourth group had normal executive functions; this group (N=32), described as having a "temporal lobe" pattern of impairment, had a significantly slower rate of progression of their dementia, with visual-construction skills virtually spared. These data demonstrate the existence of a subgroup of AD patients with a consistent pattern of impairment who progress more slowly than other patients over the course of 2 years and who maintain some specific cognitive abilities. This suggests that the mechanism of their disease may be different.

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PubMed1996

Laterality differences in quantitative and qualitative Hooper performance.

The Hooper Visual Organization Test (HVOT) is a measure of visuospatial processing commonly employed in neuropsychological assessment. Despite the well-documented relationship between visuospatial abilities and right hemisphere function, the literature has not supported a right hemisphere association with HVOT performance. The current study was conducted to examine laterality differences in HVOT performance. Sixty-seven geriatric stroke patients (44 right CVAs, 23 left CVAs) were administered the HVOT and the Mini-Mental State Exam (MMS). Results revealed significant differences between CVA groups for total score, with right CVA patients performing more poorly. Qualitative error analyses revealed highest frequencies for part responses and don't know/no response errors. Between-group differences were seen for part and unformed/unassociated errors (higher right CVA rates), and language-based errors (higher left CVA rates). Findings are consistent with theories of brain lateralization and suggest that whereas HVOT performance predominantly involves right hemisphere functions, left hemisphere dysfunction may also lead to impaired performance, and the two can be discriminated by qualitative analysis of errors.

Journal Article↗

PubMed1994

The contribution of non-insulin-dependent diabetes to lower-extremity amputation in the community.

BACKGROUND: Despite the significant public health burden of lower-extremity amputations in diabetes mellitus, few data are available on the epidemiology of lower-extremity amputations in diabetes mellitus in the community setting. METHODS: A retrospective incidence cohort study based in Rochester, Minn, was conducted. RESULTS: Among the 2015 diabetic individuals free of lower-extremity amputation at the diagnosis of diabetes mellitus, 57 individuals underwent 79 lower-extremity amputations (incidence, 375 per 100,000 person-years; 95% confidence interval, 297 to 467). Among the 1826 patients with non-insulin-dependent diabetes mellitus, 52 underwent 73 lower-extremity amputations, and the subsequent incidence of lower-extremity amputation among these residents was 388 per 100,000 person-years (95% confidence interval, 304 to 487). Of the 137 insulin-dependent diabetic patients, four subsequently underwent five lower-extremity amputations (incidence, 283 per 100,000 person-years; 95% confidence interval, 92 to 659). Twenty-five years after the diagnosis of diabetes mellitus, the cumulative risk of one lower-extremity amputation was 11.2% in insulin-dependent diabetes mellitus and 11.0% in non-insulin-dependent diabetes mellitus. When compared with lower-extremity amputation rates for Rochester residents without diabetes, patients with non-insulin-dependent diabetes mellitus were nearly 400 times more likely to undergo an initial transphalangeal amputation (rate ratio, 378.8) and had almost a 12-fold increased risk of a below-knee amputation (rate ratio, 11.8). In this community, more than 60% of lower-extremity amputations were attributable to non-insulin-dependent diabetes mellitus. CONCLUSIONS: These population-based data document the magnitude of the elevated risk of lower-extremity amputation among diabetic individuals. Efforts should be made to identify more precisely risk factors for amputation in diabetes and to intervene in the processes leading to amputation.

Amputation, Surgical↗

PubMed1993

Implicit and explicit memory following anterior communicating artery aneurysm rupture.

Several tasks examined the status of implicit and explicit memory in three patients with a ruptured anterior communicating artery (ACoA) aneurysm, one patient with bilateral temporal lobe damage sustained from herpes encephalitis (HE), 12 Alzheimer's disease (AD) patients, and 16 elderly normal controls demographically matched to the AD patients. All subjects completed word stem-completion repetition priming, pursuit-rotor tracking, and a fragmented pictures test, followed by explicit memory tests. ACoA, HE, and AD patients were impaired on all explicit tests. HE and AD patients were impaired on stem-completion priming, but were intact on other implicit tests. ACoA patients were intact on all implicit tests given. Discussion of these results considers similarities and differences in extent of basal forebrain and temporal lobe damage.

Adult↗

PubMed1993

Transfer of new learning in memory-impaired patients.

Previous research has produced conflicting evidence concerning transfer of new learning by amnesic patients. The present experiment investigated the hypothesis that different numbers of learning trials account for differences in transfer, such that the greater the number of repetitions of material in identical stimulus contexts the poorer the transfer. Six memory-impaired patients and six control subjects attempted to learn the names of business-related documents in response to descriptive definitions. Learning continued until one of the following criteria was reached: 50% correct, 100% correct, 100% correct plus 10 trials. In a transfer task, subjects were then asked to produce the target responses to altered definitional cues. The results of the experiment demonstrated that, contrary to prediction, transfer improved with numbers of learning trials. Results are consistent with the view that continued study of information allows better integration of new learning with prior knowledge and correspondingly higher levels of transfer. The theoretical implications of the findings are discussed in terms of the declarative/procedural and the episodic/semantic memory distinction. It is suggested that memory-impaired patients are capable of acquiring new semantic information although not at a normal rate. Implications for memory rehabilitation are also outlined.

Adult↗