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M C Tierney

Publications and source records attributed to M C Tierney.

At least 19 recordsLinked to original sources
PubMed2003

Prediction of transition from cognitive impairment to senile dementia: a prospective, longitudinal study.

OBJECTIVE: The purpose of this investigation was to replicate the statistical approach used in a previous investigation (Toronto study) within a French population to determine the best predictive model for Alzheimer's disease (AD). METHOD: Data from neuropsychological tests from two prospective studies were entered into a regression model. RESULTS: Replication of the statistical approach in the Montpellier sample produced a three-test model with a specificity of 99% and sensitivity of 73%. This model consisted of a delayed auditory verbal recall test, a construction test, a category fluency test and provides probability estimates for the transition to dementia in individual cases. CONCLUSION: The models derived from these two longitudinal studies provide an empirical basis for the selection of tests for the definition of mild cognitive impairment of the Alzheimer type (MCI-A). The small set of tests derived are suitable for use in general practice.

Adult↗
PubMed2001

Recognition memory and verbal fluency differentiate probable Alzheimer disease from subcortical ischemic vascular dementia.

BACKGROUND: Alzheimer disease (AD) and vascular dementia are among the most frequently occurring causes of dementia in the world, and their accurate differentiation is important because different pharmaceutical strategies may modify the course of each disease. OBJECTIVE: To determine which of 10 neuropsychological test scores can accurately differentiate patients with probable AD from those with subcortical ischemic vascular dementia (SIVD) for use in evidence-based clinical practice. DESIGN: Patients with suspected dementia were referred to the study by family physicians, geriatricians, and neurologists. All participants received a thorough assessment according to standard diagnostic guidelines. Diagnoses of probable AD (n = 31) and probable SIVD (n = 31) were made according to consensus criteria. The diagnosticians were blind to the results of the 10 neuropsychological test scores. RESULTS: There were no significant differences between the groups in age or Mini-Mental State Examination scores. Logistic regression analyses identified 2 neuropsychological tests that best distinguished the groups (sensitivity = 81%; specificity = 84%; positive likelihood ratio = 5.1). These were the recognition memory subtest of the Rey Auditory Verbal Learning Test and the Controlled Oral Word Association Test. The AD group performed better on the oral association test, whereas the SIVD group did better on the recognition memory test. CONCLUSION: Patients with probable AD and probable SIVD can be distinguished with a high degree of accuracy using these 2 neuropsychological tests.

Aged↗
PubMed2001

PET evaluation of bilingual language compensation following early childhood brain damage.

We report a positron emission tomography (PET) study in a 37-year-old, right handed, bilingual (English and American Sign Language) male with left frontal lobe damage, without evidence of language or general intellectual dysfunction. A brain MRI scan demonstrated an atrophic lesion of the left dorsolateral prefrontal, orbital, and opercular cortices extending from the frontal pole to precentral gyrus and including parts of anterior cingulate cortex, due to an probable infantile encephalitis. H(2) (15)O PET scans found evidence of increased right hemisphere activity compared to normal controls during spontaneous generation of narrative in both English and ASL. Neuropsychological data were within normal limits with the exception of visuospatial function. The results suggest the possibility that plasticity, unmasking of neural pathways, and or other adaptations of language function in the right hemisphere may have occurred, and are discussed with regard to the crowding hypothesis.

Adult↗
PubMed2000

Prediction of probable Alzheimer disease in patients with symptoms suggestive of memory impairment. Value of the Mini-Mental State Examination.

BACKGROUND: The Mini-Mental State Examination (MMSE) is a widely used diagnostic tool for dementia. Its use as a predictive indicator of probable Alzheimer disease (AD) has not been established. OBJECTIVES: To determine the accuracy of the MMSE in predicting emergent AD in a sample of patients who were referred because of symptoms suggestive of memory problems and to determine whether an abbreviated version of the MMSE could be developed that would be as accurate as the full MMSE in predicting emergent AD. DESIGN: Inception cohort of participants with symptoms suggestive of memory impairment by their family physicians were given baseline assessments, including MMSE. After 2 years, the participants' conditions were diagnosed following the standard criterion for AD. Diagnosticians were blind to baseline scores. SETTING AND PARTICIPANTS: One hundred eighty-three community-residing participants were referred by their family physicians to a university teaching hospital research investigation. After baseline screening, 165 participants were included in the study who did not have dementia and had no identifiable cause for memory impairment. After 2 years, 29 participants met criteria for AD, 98 did not develop dementia, 18 developed vascular lesions or non-AD dementia, and 20 did not return. MAIN OUTCOME MEASURE: Diagnostic classification of AD or no evidence of dementia. RESULTS: Logistic regression model was significant. At a cutoff score of 24 or less, sensitivity was 31%; specificity, 96%; with a likelihood ratio of 7.75. A reduced model of 2 subtests was identified with a sensitivity of 41%; specificity, 98%; with a likelihood ratio of 20.70. CONCLUSIONS: Results suggest that the full or abbreviated MMSE is useful in predicting emergent AD in patients with positive test results. However, it is not recommended for use as a screening or diagnostic instrument since a negative test result did not rule out emergent AD. It is recommended as a tool to identify those needing closer monitoring.

Aged↗
PubMed2000

Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment.

Fatty acid differences, including docosahexaenoic acid (DHA; 22:6n-3) have been shown in the brains of Alzheimer's patients (AD) as compared with normal age-matched individuals. Furthermore, low serum DHA is a significant risk factor for the development of AD. The relative concentration of DHA and other fatty acids, however, in the plasma of AD patients compared with patients with other kinds of dementias (other dementias; OD), patients who are cognitively impaired but nondemented (CIND), or normal patients is not known. In this study we analyzed the total phospholipid, phosphatidylcholine (PC), phosphatidylethanolamine (PE), and lysophosphatidylcholine (lysoPC) fractions of plasma from patients diagnosed with AD, OD, or CIND and compared them with a group of elderly control subjects with normal cognitive functioning. Plasma phospholipid and PC levels of 20:5n-3, DHA, total n-3 fatty acids, and the n-3/n-6 ratio were lower in the AD, OD, and CIND groups. Plasma phospholipid 24:0 was lower in the AD, OD, and CIND groups as compared with the group of control patients, and total n-6 fatty acid levels were higher in the AD and CIND groups only. In the plasma PE fraction, levels of 20:5n-3, DHA, and the total n-3 fatty acid levels were significantly lower in the AD, OD, and CIND groups. DHA levels were lower in the lysoPC fraction of CIND individuals only. There were no other differences in the fatty acid compositions of the different phospholipid fractions. Therefore, in AD, OD, and CIND individuals, low levels of n-3 fatty acids in the plasma may be a risk factor for cognitive impairment and/or dementia. Interestingly, a decreased level of plasma DHA was not limited to the AD patients but appears to be common in cognitive impairment with aging.

Aged↗
PubMed1999

Odd/Even short forms of the Boston Naming Test: preliminary geriatric norms.

It has been suggested that the 30-item version of the Boston Naming Test (BNT), in which either the odd or even items from the standard 60-item test are given, is the most psychometrically sound short form. However, no normative data are available for this version. We administered the Odd/Even BNT to 30 community-dwelling elderly individuals (age M = 72.93, range 61-84; education M = 13.73) in order to collect normative data. Odd and even forms were equivalent. The combined mean total correct score was 27.13 (SD = 2.06), a score consistent with that derived by retrospective extraction in the original odd/even test construction study. Each form discriminated normals from age- and education-matched patients with probable Alzheimer's disease, suggesting criterion-related validity.

Aged↗
PubMed1998

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS): preliminary clinical validity.

Neuropsychological assessment of older individuals with dementing illnesses has suffered from a lack of appropriately designed test instruments. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was developed for the dual purposes of identifying and characterizing abnormal cognitive decline in the older adult and as a neuropsychological screening battery for younger patients. The entire battery takes less than 30 minutes to administer, and yields scaled scores for five cognitive domains. The current study reports preliminary clinical validity results with the RBANS, comparing very mildly demented patients with a diagnosis of probable Alzheimer's disease (n = 20) to patients with Huntington's disease (n = 20) and normal controls (n = 40). Although the patient groups had essentially identical total scores on the RBANS, they exhibited opposite profiles, differing significantly on four of the five subsections. The AD patients performed most poorly on Language, and Delayed Memory subsections, while the HD patients obtained their lowest scaled scores on the Attention and the Visuospatial/Constructional subsections. These results are consistent with the neuropsychological profiles of these dementing disorders derived from lengthier standardized tests and experimental investigations. In addition, even those patients who performed above the suggested cut-off points on the MMSE and the Dementia Rating Scale scored significantly below their controls on the RBANS. These data suggest that the RBANS is effective at both detecting and characterizing dementia of different etiologies.

Aged↗
PubMed1997

Domain specificity of the subtests of the Mini-Mental State Examination.

OBJECTIVE: To examine the convergent and, for the first time to our knowledge, the divergent validity of 4 of the subtests of the Mini-Mental State Examination (MMSE): attention, naming, memory, and copy. METHODS: Participants included 126 memory-impaired individuals (mean age, 74 years). Because the naming subtest showed no variability, we did not analyze it further. RESULTS: The convergent validity of the attention, memory, and copy subtests was confirmed with Spearman rank correlation coefficient. Each MMSE subtest was significantly related to a parallel neuropsychological test. We measured divergent validity by testing the difference between the MMSE subtest correlation with its parallel neuropsychological test and its nonparallel neuropsychological test. The MMSE subtests of attention and memory showed similar relationships with their parallel neuropsychological tests as they did with nonparallel neuropsychological tests of attention, memory, and naming. These 2 subtests, however, did show divergence from a neuropsychological test of copy, most likely indicating that these 2 MMSE subtests are measuring the verbal (and not the performance) domain. The MMSE subtest of copy showed the poorest convergent and divergent validity. CONCLUSIONS: The 3 subtests did not show sufficient divergent validity to warrant a conclusion of their domain specificity. Thus, when a more detailed diagnostic profile is required, a thorough neuropsychological evaluation will provide a more valid description of an individual's cognitive profile.

Aged↗
PubMed1997

Postdicting verbal IQ of elderly individuals.

We undertook a longitudinal crossvalidation of the Ryan and Paolo (1992) equation's ability to postdict Wechsler Adult Intelligence Scale-Revised (WAIS-R) Verbal IQ (VIQ) from National Adult Reading Test (NART) performance measured 5 years after VIQ scores were obtained, for a sample of 49 elderly normal individuals (mean age 71 years). Five-year interval postdiction accuracy agreed very well with the results of the original, concurrent study. Clinical utility is still limited, however, as VIQ must decline by 16.3 points for 95%-detection sensitivity. A new regression equation that utilizes a combination of NART errors and WAIS-R Vocabulary age-scaled scores (measured 3 years earlier) provided slightly better expected clinical sensitivity and accounted for 49% of the variance in VIQ scores.

Aged↗
PubMed1996

The prediction of Alzheimer disease. The role of patient and informant perceptions of cognitive deficits.

OBJECTIVE: To determine whether the perceptions of patients' cognitive deficits by either the patient or an informant could predict who would develop Alzheimer disease (AD) in a group of 120 memory-impaired patients without dementia. METHODS: At entry into the study, patients were assessed by several measures that included neuropsychological tests and the Cambridge Mental Disorders of the Elderly Examination Interview Schedule. The latter schedule asks patients and their informants about their perceptions of cognitive deficits in the patients. After 2 years, patients underwent a diagnostic workup for AD: 29 had developed probable AD, whereas the other 91 did not develop dementia. We used logistic regression analyses to examine the predictive accuracy of patients' and informants' perceptions of deficits at entry into the study. RESULTS: Informants' perceptions, not patients' perceptions, contributed significantly to the prediction of AD. The best prediction of AD was obtained by the regression model that included both informants' perceptions and 2 neuropsychological tests. CONCLUSIONS: These results demonstrate the clinical use of including informant perceptions about patients' cognitive deficits in the diagnostic assessment of AD. They also indicate that patients' perceptions of their own deficits are not predictive of AD, but are related to depressive affect.

Aged↗
PubMed1996

A prospective study of the clinical utility of ApoE genotype in the prediction of outcome in patients with memory impairment.

Given the relationship between the presence of ApoE epsilon 4 and Alzheimer's disease (AD), were studied whether knowledge of epsilon 4 status would predict which memory-impaired patients would develop AD over time. One hundred seven patients who presented with memory impairment but not dementia were referred to the study by their family physicians. These patients were followed prospectively over a 2-year period. Twenty-nine patients developed AD, while 78 did not develop dementia. We found that ApoE genotype was a reliable prognostic indicator of who developed AD in this group only when memory test performance was included in the predictive model. These findings indicate that limitations of ApoE genotyping in isolation as a prognostic indicator of AD. Because this study included prospectively selected patients who were followed longitudinally, our findings are likely to have more relevance in the clinical setting than those obtained from currently available retrospective studies.

Aged↗
PubMed1996

Prediction of probable Alzheimer's disease in memory-impaired patients: A prospective longitudinal study.

We determined whether a battery of neuropsychological tests could predict who would develop Alzheimer's disease (AD) in a group of 123 memory-impaired nondemented patients. Patients were followed longitudinally for 2 years with a research battery of neuropsychological tests. After 2 years, 29 developed probable AD, and 94 did not develop dementia. We used logistic regression analyses to examine the classification accuracy of subjects' performance at entry to the study on the research battery. The logistic regression model was significant with an accuracy of 89%, sensitivity of 76%, and specificity of 94%. Two tests contributed significantly to this model: the delayed recall from the Rey Auditory Verbal Learning Test and the Mental Control subtest of the Wechsler Memory Scale. These two tests alone produced the same accuracy, sensitivity, and specificity as the larger model. These results demonstrate that probable AD can be predicted with a high degree of accuracy and with a relatively brief battery of neuropsychological tests.

Alzheimer Disease↗
PubMed1995

Implicit memory in Alzheimer's disease.

While patients with Huntington's disease (HD) and Korsakoff's syndrome (KS) demonstrate "preserved" performance on implicit word-stem completion tasks, patients with Alzheimer's disease (AD) are typically found to be impaired. It has been hypothesized that AD patients do poorly as a result of degenerative changes in posterior cortical association areas thought to mediate performance on this type of implicit memory task, and that the relative sparing of these areas in KS and HD results in their "preserved" performance. The present study was undertaken to examine the implicit memory performance of AD patients on this task after equating their explicit performance to that of normal controls by manipulating the number of encoding exposures. When this was accomplished, the implicit memory performance of AD patients was equivalent to that of controls. The results are discussed within the context of a critical review of the evidence for the existence of separable neural systems in mediating implicit and explicit memory.

Aged↗
PubMed1994

D-cycloserine treatment of Alzheimer disease.

Degeneration of cortical glutamatergic projections may contribute to the cognitive decline in Alzheimer disease (AD). To evaluate whether 1glutamate system stimulation might confer symptomatic benefit, we administered D-cycloserine, a putative partial indirect agonist at certain N-methyl-D-aspartate (NMDA) glutamate receptors, to 12 patients with probable AD. The patients (seven men, five women) had a mean age of 65 +/- 8.4 years; Mini Mental State Examination scores ranged from 15 to 25. A dose escalation phase, in which cycloserine was given in daily oral doses from 25 to 500 mg (total of six dose levels, 1 week per dose), was followed by a "best dose" crossover comparison with placebo under double-blind conditions. The crossover phase consisted of 2 weeks of cycloserine and 2 weeks of placebo, separated by a 1-week washout period. We observed no significant or consistent effect on neuropsychological outcome measures. The results suggest that short-term potentiation of NMDA-mediated glutamatergic transmission may not prove useful in the symptomatic treatment of Alzheimer dementia.

Aged↗
PubMed1991

On the clinical value of the London Psychogeriatric Rating Scale.

The London Psychogeriatric Rating Scale (LPRS) was administered to 76 probable Alzheimer's patients, 59 patients with dementia unrelated to Alzheimer's, 102 neurologically normal subjects, and 27 patients with symptoms of both Alzheimer's and dementia of other etiologies. By examining the relationships among the four subscales of the LPRS and conducting factor analyses, it was demonstrated that the four subscales were not measuring different phenomena. The internal consistency of the full 36-item scale was high (Cronbach's Alpha = 0.96) indicating the total LPRS score provided a reliable global index of behavioral function. The total LPRS scores correlated with the independently administered Goldfarb Mental Status Examination scores (r = -0.79). The LPRS differentiated between the normals and the combined demented groups and between inpatients and outpatients. The LPRS continues to have clinical value for functional assessments in a non-intrusive manner. The LPRS may be particularly useful in situations where direct assessment of mental status is not practical.

Aged↗
PubMed1990

The place of cooperation in the examination of neuropsychological impairment.

We examined the relationship between ratings of patient cooperation and neuropsychological test performance in a sample (N = 333) of dementing patients and normal controls. We also examined the stability of the relationship in a subset of this same sample (N = 299) who were retested a year later. All the correlation coefficients in both years were significant, with a median Pearson of.64 in year one and.725 in year two. The test-retest reliability for ratings of cooperativeness over the one-year time period (rated by different examiners) was also significant,r =.64 (p <.0001). This analysis indicates that cooperation plays a significant role in neuropsychological test performance and that ratings of cooperativeness are relatively stable over periods of up to a year in length.

Journal Article↗