Biomedical subjects

Jerome A Yesavage

Publications and source records attributed to Jerome A Yesavage.

At least 19 recordsLinked to original sources

PubMed2006

The Cost-Time Index: a new method for measuring the efficiencies of recruitment-resources in clinical trials.

Paid media are important resources used to recruit subjects in clinical trials. An index for evaluating which advertising resource has minimal cost and time requirement for patient accrual, for a given study design, has not been previously introduced. In this communication the authors present a new index, the Cost-Time Index, which represents a measure of the average amount of money and time spent, simultaneously, on a given advertising resource to recruit one analyzable subject. This index can be calculated using retrospective data and may be a useful tool for comparing recruitment efficiencies among various resources. The authors demonstrate the utility of the Cost-Time Index and recommend its use as an additional variable in future studies regarding recruitment strategies in clinical trials.

Advertising↗

PubMed2006

Caution regarding the use of pilot studies to guide power calculations for study proposals.

Clinical researchers often propose (or review committees demand) pilot studies to determine whether a study is worth performing and to guide power calculations. The most likely outcomes are that (1) studies worth performing are aborted and (2) studies that are not aborted are underpowered. There are many excellent reasons for performing pilot studies. The argument herein is not meant to discourage clinical researchers from performing pilot studies (or review committees from requiring them) but simply to caution against their use for the objective of guiding power calculations.

Biomedical Research↗

PubMed2006

Strategies to reduce site differences in multisite studies: a case study of Alzheimer disease progression.

OBJECTIVES: The objectives of this study were to evaluate the magnitude and sources of site differences in a multisite study of rates of cognitive decline among patients with Alzheimer disease and to seek strategies to reduce the magnitude of site differences in this and future such studies. METHODS: A total of 3,280 participants from 15 different sites was analyzed. For each participant, the average rate of change in the Mini-Mental State Examination (MMSE) was calculated. Participants who declined at least three MMSE points per year were classified "rapid decliners." Site differences in sociodemographic distributions and the percentage of rapid decliners were examined, and a signal detection approach was used to identify the main correlates of rapid decline. RESULTS: The percentage of rapid decliners for the 15 sites initially varied from 8%-40%. Two of the correlates of rapid decline were largely the result of different sampling protocols, namely baseline MMSE and elapsed time between the first and last MMSE. By selecting only those participants at each site with a baseline MMSE between 15 and 23, and limiting the follow-up time to a period of 11-24 months, the authors created greater homogeneity in the protocols across sites and reduced site variability of rapid decliners from 27%-50%. CONCLUSION: Results of single-site studies are often nonreproducible, and multisite studies that follow different protocols and do not take site differences into account may be misleading. This study indicates the importance of site differences and how relatively simple efforts to impose common sampling, measurement, and design criteria can reduce, if not totally remove, site differences.

Aged↗

PubMed2006

No improvement of posttraumatic stress disorder symptoms with guanfacine treatment.

OBJECTIVE: The authors report an 8-week, double-blind, randomized controlled trial of guanfacine versus placebo for posttraumatic stress disorder (PTSD). METHOD: Veterans with chronic PTSD who were medication-free or receiving stable pharmacotherapy were randomly assigned to guanfacine (N=29) versus placebo (N=34). RESULTS: Guanfacine had no effect on PTSD symptoms, subjective sleep quality, or general mood disturbances. Guanfacine was associated with a number of side effects. CONCLUSIONS: These results do not support the use of alpha 2 agonists in veterans with chronic PTSD.

Adrenergic alpha-Agonists↗

PubMed2006

Factors associated with psychiatric hospitalization of individuals diagnosed with dementia and comorbid bipolar disorder.

The objective was to determine risk factors of psychiatric hospitalization among a Veterans Administration database of patients with dementia and comorbid bipolar disorder (D+BD). Patients with D+BD had a greater prevalence of psychiatric hospitalization (28% vs 4%). The strongest predictor of psychiatric hospitalization was the presence of an alcohol use disorder (51% risk); patients without alcohol use disorders but under the age of 70 had the next highest risk (33% risk). However, patients with an alcohol use disorder had shorter psychiatric hospitalizations than those without. Compared with patients without BD, D+BD patients were more likely to have alcohol use disorders (15% vs 3%) and any other substance use problem (10% vs 1%). In patients diagnosed with dementia and bipolar disorder, the strongest risk factor for psychiatric hospitalization was an alcohol abuse disorder. These findings suggest that disorders with increased frequency in BD affect the course of dementia.

Age Factors↗

PubMed2005

Factors in choosing atypical antipsychotics: toward understanding the bases of physicians' prescribing decisions.

OBJECTIVE: Off-label prescribing of medications, polypharmacy, and other questionable prescribing practices have led investigators to examine a large VA pharmacy database to determine if physician prescribing decisions appear reasonable. METHOD: The current study addresses the question of physician prescribing of atypical antipsychotics in 34,925 veterans with schizophrenia, using a series of signal detection analyses. RESULTS: These results suggest that only three factors (hospital size, age, and secondary diagnosis) allow classification of patients prescribed atypicals into three groups with frequencies of use of atypicals ranging from 43% to 79%, and that these results are consistent with reasonable clinical practice. CONCLUSIONS: Results of two-stage signal detection analyses are readily interpretable by clinicians and administrators who are faced with the task of evaluating how physicians prescribe medications in clinical practice. Physicians' decisions to prescribe atypical antipsychotics are based on both patient and fiscal considerations. This likely reflects a combination of clinical judgment and institutional guidelines.

Antipsychotic Agents↗

PubMed2005

The development and initial validation of the Terminally Ill Grief or Depression Scale (TIGDS).

Patients often experience 'preparatory-grief' as they cope with the dying process. Some may be depressed. The Terminally Ill Grief or Depression Scale (TIGDS), comprising grief and depression sub-scales, is a new self-report measure designed to differentiate between preparatory-grief and depression in adult inpatients. The initial 100-item inventory was assembled based on literature review, interviews with clinicians and dying patients and then shortened to 42 items based on consensus expert opinion. Validity and reliability were tested in a sample of 55 terminally ill adults. The consensus clinical opinion was used as the gold standard to differentiate between preparatory grief and depression. The intra-class correlation coefficient was high (it was calculated to estimate the test-retest reliability for the 47 patients who had completed the TIGDS twice--retest was administered 2 to 7 days after the initial test), ranging from 0.86 (grief) to 0.97 (depression). The validity of TIGDS was assessed using a receiver operating characteristic curve analysis, comparing the first test with the clinical criterion. The first and only variable and cut-point was the depression score (chi-square = 18.4, p < 0.001, cut point = 3). The sensitivity of the TIGDS was 0.727 and specificity was 0.886 for the depression = 3 cutoff score. The construct validity of the TIGDS was tested by comparing with the Hospital Anxiety and Depression Scale (HADS). The TIGDS depression subscale showed strong convergent validity and the TIGDS grief subscale showed strong discriminant validity with the HADS total score.

Aged↗

PubMed2005

Cognitive ability, expertise, and age differences in following air-traffic control instructions.

Differences in cognitive ability and domain-specific expertise may help explain age differences in pilot performance. Pilots heard air-traffic controller messages and then executed them while "flying" in a simulator. Messages varied in length and speech rate. Age was associated with lower accuracy, but the expected Age x Message Difficulty interactions were not obtained. Expertise, as indexed by pilot ratings, was associated with higher accuracy; yet expertise did not reduce age differences in accuracy. The effect of age on communication task accuracy was largely explainable as an age-associated decrease in working memory span, which in turn was explainable as decreases in both speed and interference control. Results are discussed within frameworks of deliberate practice and cognitive mediation of age differences.

Age Distribution↗

PubMed2005

Hormone replacement therapy and longitudinal cognitive performance in postmenopausal women.

OBJECTIVE: The authors examined the impact of hormone replacement therapy (HRT) on longitudinal cognitive performance (controlling for mood state) in 69 community-dwelling, postmenopausal women. METHODS: The authors conducted a 5-year follow-up of cognitive performance in 37 postmenopausal HRT users and 32 non-users. The groups did not differ with respect to age, years of education, or inter-test interval. RESULTS: No main effect of HRT was observed on any of the cognitive measures, and depressive symptomatology did not affect the relationship between HRT and cognition. CONCLUSION: Overall, our findings do not suggest that HRT affects longitudinal cognitive performance in postmenopausal, community-dwelling older women.

Adult↗

PubMed2004

VA practice patterns and practice guidelines for treating posttraumatic stress disorder.

Little is known about how recent ISTSS practice guidelines (E. B. Foa, T. M. Keane, & M. J. Friedman, 2000) compare with prevailing PTSD treatment practices for veterans. Prior to guideline dissemination, clinicians in 6 VA medical centers were surveyed in 1999 (n = 321) and in 2001 (n = 271) regarding their use of various assessment and treatment procedures. Practices most consistent with guideline recommendations included psychoeducation, coping skills training, attention to trust issues, depression and substance use screening, and prescribing of SSRIs, anticonvulsants, and trazodone. PTSD and trauma assessment, anger management, and sleep hygiene practices were provided less consistently. Exposure therapy was rarely used. Additional research is needed on training, clinical resources, and organizational factors that may influence VA implementation of guideline recommendations.

Depression↗

PubMed2004

Sleep/wake disruption in Alzheimer's disease: APOE status and longitudinal course.

Disturbed sleep is a major clinical problem in Alzheimer's disease (AD). Apolipoprotein epsilon4 (APOE epsilon4) carrier status may increase risk of AD, yet there are no data on relations between APOE status and progression of sleep disturbance in AD. The objective of this study was to determine if sleep parameters in AD patients change over time as a function of APOE carrier status. Forty-four community-dwelling AD patients with diagnosis of probable AD were followed from early stages of disease. Their sleep/wake parameters were compared according to APOE status. For APOE epsilon4 carriers, only wake after sleep onset (WASO) increased in association with lower cognitive function as indicated by the Mini-Mental State Examination (MMSE); for non-epsilon4 subjects, increases in WASO and declines in total sleep time, sleep efficiency, and the amplitude of the rest/activity circadian rhythm over time were associated with lower performance on the MMSE. In these data, APOE status was associated with the progression of sleep/wake disturbances in AD. Overall, there was greater deterioration on sleep parameters in patients negative for the epsilon4 allele.

Aged↗

PubMed2004

Validation of a 26-point telephone version of the Mini-Mental State Examination.

The objective of this study was to assess the convergent validity of a 26-point Telephone Mini-Mental State Examination (MMSE) in a longitudinal cohort of 46 Alzheimer's disease (AD) patients. Paired in-person and telephone MMSE observations were collected within 35 days of each other. The setting was the Stanford/VA Alzheimer's Center in Palo Alto, California, and patients' residences. The 30-point Folstein MMSE was administered in-person, and a 26-point telephone version of the MMSE, adapted from the Adult Lifestyles and Function Interview (ALFI)-MMSE. Total scores for the in-person and telephone MMSE versions correlated strongly (Pearson's r =.88, P <.001). Hearing impairment and education level did not significantly affect telephone-based performance. The Telephone MMSE can be used to validly estimate in-person MMSE scores of patients with AD. Use of this practical measure can enhance reassessment if returning to the clinic is difficult or if a change in the patient's medical condition merits a check of mental status by telephone.

Aged↗

PubMed2003

Psychoactive drugs and pilot performance: a comparison of nicotine, donepezil, and alcohol effects.

The cholinergic system plays a major role in cognitive abilities that are essential to piloting an aircraft: attention, learning, and memory. In previous studies, drugs that enhance the cholinergic system through different pharmacologic mechanisms have shown beneficial effects on cognition; but dissimilar cognitive measures were used and samples were not comparable. A comparison within the same cognitive tasks, within comparable samples appears desirable. Toward this aim, we compared effect sizes (ES) of performance-enhancing doses of nicotine (a nicotinic receptor agonist) and donepezil (an acetylcholinesterase inhibitor) as found in our prior work on pilot performance. We also compared cholinergic ES to those of performance-impairing doses of alcohol. In three randomized, placebo-controlled trials, we assessed the flight performance of aircraft pilots in a Frasca 141 simulator, testing I: the acute effects of nicotine gum 2 mg; II: the effects of administration of 5 mg donepezil/day for 30 days; and III: the acute and 8 h-carryover effects of alcohol after a target peak BAC of 0.10%. We calculated the ES of nicotine, donepezil, and alcohol on a flight summary score and on four flight component scores. Compared to placebo, nicotine and donepezil significantly improved, while alcohol significantly impaired overall flight performance: ES (nicotine)=0.80; ES (donepezil)=1.02; ES (alcohol acute)=-3.66; ES (alcohol 8 h)=-0.82. Both cholinergic drugs showed the largest effects on flight tasks requiring sustained visual attention. Although the two tested cholinergic drugs have different pharmacologic mechanisms, their effects on flight performance were similar in kind and size. The beneficial effects of the cholinergic drugs on overall flight performance were large and the absolute (ie nondirectional) sizes were about one-fourth of the absolute ES of acute alcohol intoxication and roughly the same as the absolute 8 h-carryover ES of alcohol.

Adult↗

PubMed2003

Use of an external mnemonic to augment the efficacy of an internal mnemonic in older adults.

OBJECTIVES: To evaluate the impact of external memory devices on the efficacy of a package of internal mnemonic techniques. Participants wrote two types of lists during the study phase: (a) a list of study words and/or (b) a loci list. At recall, participants were not allowed to refer to either of the lists they had written during the study. DESIGN: 2 x 2 factorial with writing study words ("write" or "not write") and writing down a previously established loci list ("write" or "not write") manipulated as between-participants variables. PARTICIPANTS: 68 community-dwelling adults 55 years of age and older who wished to improve their memory. MEASUREMENTS: Free word recall. RESULTS: There were statistically significant effects of writing the loci list, but not of writing the list of study words. Scores were higher when participants wrote the loci lists compared to when they did not. CONCLUSIONS: Use of external mnemonics may enhance the efficacy of internal mnemonics, even when the external mnemonic is not used at the time of recall.

Activities of Daily Living↗

PubMed2003

Differential associations between entorhinal and hippocampal volumes and memory performance in older adults.

Magnetic resonance imaging-derived entorhinal and hippocampal volumes were measured in 14 nondemented, community-dwelling older adults. Participants were selected so that memory scores from 2 years prior to scanning varied widely but were not deficient relative to age-appropriate norms. A median split of these memory scores defined high-memory and low-memory groups. Verbal memory scores at the time of imaging were lower, and entorhinal and hippocampal volumes were smaller, in the low-memory group than in the high-memory group. Left entorhinal cortex volume showed the strongest correlation (r= .79) with immediate recall of word lists. Left hippocampal volume showed the strongest correlation (r= .57) with delayed paragraph recall. These results suggest that entorhinal and hippocampal volumes are related to individual differences in dissociable kinds of memory performance among healthy older adults.

Aged↗

PubMed2003

Development of diagnostic criteria for defining sleep disturbance in Alzheimer's disease.

This article proposes new standards for identifying, defining, and naming sleep/wake cycle disturbances associated with Alzheimer's disease (AD) to aid in more effective research, including the development and testing of potential treatments. Many AD patients develop sleep/wake cycle disturbances associated with distress, depression, and sleep disturbances in the caregiver, as well as early nursing home placement for the patient. The Food and Drug Administration Psychopharmacological Drugs Advisory Committee has emphasized the need for a comprehensive diagnostic system. A key point made by the committee was that behavioral problems associated with dementia (including sleep and chronobiological disturbances) are scientifically and clinically valid targets of pharmacologic treatment. However, current diagnostic criteria preclude development of FDA-acceptable studies of pharmacological interventions because they do not include the required specific indications for treatment. This article attempts to develop better-defined provisional criteria with the goal of promoting epidemiological, physiological, and, especially, pharmacological research on sleep/wake disturbances.

Aged↗

PubMed2002

Variable effects of aging on frontal lobe contributions to memory.

Declarative memory declines with age, but there is profound variation in the severity of this decline. Healthy elderly adults with high or low memory scores and young adults viewed words under semantic or non-semantic encoding conditions while undergoing fMRI. Young adults had superior memory for the words, and elderly adults with high memory scores had better memory for the words than those with low memory scores. The elderly with high scores had left lateral and medial prefrontal activations for semantic encoding equal to the young, and greater right prefrontal activation than the young. The elderly with low scores had reduced activations in all three regions relative to the elderly with high memory scores. Thus, successful aging was characterized by preserved left prefrontal and enhanced right prefrontal activation that may have provided compensatory encoding resources.

Adult↗

PubMed2002

Ethical, and practical issues in applying functional imaging to the clinical management of Alzheimer's disease.

This review outlines ethical, legal, and practical issues related to conducting functional imaging research with Alzheimer's disease (AD) patients. Imaging techniques, with an emphasis on functional MRI and positron emission tomography, are compared and contrasted with respect to the manner in which they can be applied to issues of clinical relevance to AD. Methodological difficulties are raised to assist with critical evaluation of current imaging results. Various potential clinical applications of functional imaging are briefly reviewed and discussed with respect to associated ethical conflicts.

Aged↗