Standardized regression based (SRB) formulas, a method for predicting cognitive change across time, traditionally use baseline performance on a neuropsychological measure to predict future performance on that same measure. However, there are instances in which the same tests may not be given at follow-up assessments (e.g., lack of continuity of provider, avoiding practice effects). The current study sought to expand this methodology by developing SRBs to predict performance on different tests within the same cognitive domain. Using a sample of 127 non-demented community-dwelling older adults assessed at baseline and after one year, two sets of SRBs were developed: 1. those predicting performance on the same test, and 2. those predicting performance on a different test within the same cognitive domain. The domains examined were learning and memory, processing speed, and language. Across both sets of SRBs, one year scores were significantly predicted by baseline scores, especially for the learning and memory and processing speed measures. Although SRBs developed for the same test were comparable to those developed for different tests within the same domain, less variance was accounted for as tests became less similar. The current results lend preliminary support for additional development of SRBs, both for same- and different-tests, as well as beginning to examine domain-based SRBs.
Predicting cognition; standardized based regression
Neuropsychologists are often asked to answer questions about the effects of cognitive deficits on everyday functioning. This study examined the relationship between and the cognitive correlates of self-report, performance-based, and direct observation measures commonly used as proxy measures for everyday functioning. Participants were 88 community-dwelling, cognitively healthy older adults (age 50–86 years). Participants completed standardized neuropsychological tests and questionnaires, and performed eight activities of daily living (e.g., water plants, fill a medication dispenser) while under direct observation in a campus apartment. All proxy measures of everyday function were sensitive to the effects of healthy cognitive aging. After controlling for age, cognitive predictors explained a unique amount of the variance for only the performance-based behavioral simulation measure (i.e., Revised Observed Tasks of Daily Living). The self-report instrumental activities of daily living (IADL) and the performance-based everyday problem-solving test (i.e., EPT) did not correlate with each other; however, both were unique predictors of the direct observation measure. These findings suggest that neuropsychologists must be cautious in making predictions about the quality of everyday activity completion in cognitively healthy older adults from specific cognitive functions. The findings further suggest that a self-report of IADLs and the performance-based EPT may be useful measures for assessing everyday functional status in cognitively healthy older adults.
Activities of daily living; Cognitive correlates; Functional status; Aging; Instrumental activities of daily living; Everyday functioning
Practice effects, defined as improvements in cognitive test performance due to repeated exposure to the test materials, have traditionally been viewed as sources of error. However, they might provide useful information for predicting cognitive outcome. The current study used three separate patient samples (older adults with mild cognitive impairments, individuals who were HIV +, individuals with Huntington’s disease) to examine the relationship between practice effects and cognitive functioning at a later point. Across all three samples, practice effects accounted for as much as 31 to 83% of the variance in the follow-up cognitive scores, after controlling for baseline cognitive functioning. If these findings can be replicated in other patients with neurodegenerative disorders, clinicians and researchers may be able to develop predictive models to identify the individuals who are most likely to demonstrate continued cognitive decline across time. The ability to utilize practice effects data would add a simple, convenient, and non-invasive marker for monitoring an individual patient’s cognitive status. Additionally, this prognostic index could be used to offer interventions to patients who are in the earliest stages of progressive neurodegenerative disorders.
practice effects; cognitive outcome; Mild Cognitive Impairment; HIV; Huntington’s disease
Assessing cognitive change during a single visit requires the comparison of estimated premorbid abilities and current neuropsychological functioning. Although premorbid intellect has been widely examined, estimating premorbid memory abilities has received less attention. The current study used demographic variables and an estimate of premorbid intellect to predict premorbid memory abilities in a sample of 95 community-dwelling, cognitively intact older adults. These prediction formulae were then applied to a sample of 74 individuals with amnestic Mild Cognitive Impairment to look for discrepancies between premorbid and current memory abilities. Despite minimal differences between premorbid and current memory abilities in the intact sample, large and statistically significant differences were observed in the impaired sample. Although validation in larger samples is needed, the current estimates of premorbid memory abilities may aid clinicians in determining change across time.
Predicting cognition; learning and memory; assessment
Practice effects have been widely reported in healthy older adults, but these improvements due to repeat exposure to test materials have been more equivocal in individuals with mild cognitive impairment (MCI).
The current study examined short-term practice effects in MCI by repeating a brief battery of cognitive tests across one week in 59 older adults with amnestic MCI and 62 intact older adults.
Participants with amnestic MCI showed significantly greater improvements on two delayed recall measures (p < 0.01) compared to intact peers. All other practice effects were comparable between these two groups. Practice effects significantly improved scores in the MCI group so that 49% of them were reclassified as “intact” after one week, whereas the other 51% remained “stable” as MCI. Secondary analyses indicated the MCI-Intact group demonstrated larger practice effects on two memory measures than their peers (p < 0.01).
These results continue to inform us about the nature of memory deficits in MCI, and could have implications for the diagnosis and possible treatment of this amnestic condition.
mild cognitive impairment; practice effects; repeat testing
Practice effects on cognitive tests have been shown to further characterize patients with amnestic Mild Cognitive Impairment (aMCI), and may provide predictive information about cognitive change across time. We tested the hypothesis that a loss of practice effects would portend a worse prognosis in aMCI.
Longitudinal, observational design following participants across one year.
Three groups of older adults: 1. cognitively intact (n=57), 2. aMCI with large practice effects across one week (MCI+PE, n=25), and 3. aMCI with minimal practice effects across one week (MCI−PE, n=26).
After controlling for age and baseline cognitive differences, the MCI−PE group performed significantly worse than the other groups after one year on measures of immediate memory, delayed memory, language, and overall cognition.
Although these results need to be replicated in larger samples, the loss of short-term practice effects portends a worse prognosis in patients with aMCI.
Mild Cognitive Impairment; practice effects; dementia
Mild cognitive impairment (MCI) is proposed to be a prodrome to dementia in some older adults. However, the presentation of MCI in the community can differ substantially from clinic-based samples. The aim of the current study is to demonstrate the effects of different operational definitions of MCI on prevalence estimates in community-dwelling older adults. A consecutive series of 200 participants aged 65 and over from the Adult Changes in Thought (ACT) community-based cohort were approached to undergo comprehensive neuropsychological and medical evaluation; 159 were included in the final analyses. Nondemented subjects were categorized using various diagnostic criteria for MCI. In a novel approach, neuropsychological test scores were evaluated using an individualized benchmark as a point of test comparison, as well as traditional methods that entail comparison to age-based normative data. Diagnostic criteria were further subdivided by severity of impairment (1.0 vs. 1.5 standard deviations [sd] below the benchmark) and extent of impairment (based on a single test or an average of tests within a cognitive domain). MCI prevalence rates in the sample were highly dependent on these diagnostic factors, and varied from 11% to 92% of the sample. Older groups tended to show higher prevalence rates, although this was not the case across all diagnostic schemes. The use of an individualized benchmark, less severe impairment cutoff, and impairment on only a single test all produced higher rates of MCI. Longitudinal follow-up will determine whether varying diagnostic criteria improves sensitivity and specificity of the MCI diagnosis as a predictor for dementia.
Age related memory disorders; aging; cognition; Alzheimer's disease; dementia; diagnosis; epidemiology; individual differences; neuropsychological tests; prevalence; normative
Significant declines in longitudinal comparisons of neurocognitive performance are seldom evident until adults are in their 60s or older, but relatively little is known about the existence, or nature, of age-related changes at earlier periods in adulthood. The current research was designed to address this issue by examining characteristics of change in measures from 12 neuropsychological and cognitive tests at different periods in adulthood. Although change was largely positive for adults under about 55 years of age and frequently negative for adults at older ages, the reliabilities of the changes in the neuropsychological and cognitive variables were similar at all ages. Furthermore, there were few systematic relations of age on the reliability-adjusted correlations between the changes in composite scores representing different abilities. These results imply that although neurocognitive declines may not be apparent at young ages because of positive retest effects or other factors, at least in some respects longitudinal changes may have nearly the same meaning across all of adulthood.
aging; cognitive change; longitudinal; reliability
Reliable detection and quantification of longitudinal cognitive change are of considerable importance in many neurological disorders, particularly to monitor central nervous system effects of disease progression and treatment. In the current study, we developed normative data for repeated neuropsychological (NP) assessments (6 testings) using a modified Standard Regression-Based (SRB) approach in a sample that includes both HIV-uninfected (HIV−, N=172) and neuromedically stable HIV-infected (HIV+, N=124) individuals. Prior analyzes indicated no differences in NP change between the infected and uninfected participants. The norms for change included correction for factors found to significantly affect follow-up performance, using hierarchical regression. The most robust and consistent predictors of follow-up performance were the prior performance on the same test (which contributed in all models) and a measure of prior overall NP competence (predictor in 97% of all models). Demographic variables were predictors in 10%-46% of all models and in small amounts; while test retest interval contributed in only 6% of all models. Based on the regression equations, standardized change scores (z-scores) were computed for each test measure at each interval; these z scores were then averaged to create a total battery change score. An independent sample of HIV− participants who had completed 8 of the 15 tests was used to validate an abridged summary change score. The normative data are available in an electronic format by email request to the first author. Correction for practice effects based on normative data improved the consistency of NP impairment classification in a clinically stable longitudinal cohort after baseline.
Normative data; longitudinal studies; regression; regression change score; SRB; practice effect
Cognitive training improves mental abilities in older adults, but the trainability of persons with memory impairment is unclear. We conducted a subgroup analysis of subjects in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) trial to examine this issue. ACTIVE enrolled 2802 non-demented, community-dwelling adults aged 65 years and older and randomly assigned them to one of four groups: Memory training, reasoning training, speed-of-processing training, or no-contact control. For this study, participants were defined as memory-impaired if baseline Rey Auditory Verbal Learning Test (AVLT) sum recall score was 1.5 SD or more below predicted AVLT sum recall score from a regression-derived formula using age, education, ethnicity, and vocabulary from all subjects at baseline. Assessments were taken at baseline (BL), post-test, first annual (A1), and second annual (A2) follow-up. One hundred and ninety-three subjects were defined as memory-impaired and 2580 were memory-normal. Training gain as a function memory status (impaired vs. normal) was compared in a mixed effects model. Results indicated that memory-impaired participants failed to benefit from Memory training but did show normal training gains after reasoning and speed training. Memory function appears to mediate response to structured cognitive interventions in older adults.
Cognition; Memory; Mild cognitive impairment; Aging; Therapeutics; Clinical trial; Psychological technique
The objective of this study was to investigate the effects of a structured 6-week neuropsychological course on the executive functioning of older adults with cognitive complaints.
A randomised controlled design was used involving 69 community dwelling individuals aged 55 years and older. Both objective and subjective measures were included to assess executive functioning. General linear model with repeated measures analysis of variance was used to examine the intervention effects.
After the intervention, the participants in the intervention group were significantly less annoyed by their cognitive failures, were better able to manage their executive failures and reported less anxiety symptoms than those in the waiting list control group.
These findings indicate that a combination of psycho-education and training has the potential to change the attitude of older individuals towards their cognitive functioning.
Because this training focussed on cognitive functions that are among the first to decline in older adults and the subjective evaluation of the people after training was quite favourable, the proposed intervention may be considered a valuable contribution to cognitive interventions for older adults.
Aging; Cognitive functioning; Executive functioning; Training; Psycho-education
In the community at large, many older adults with minimal cognitive and functional impairment remain stable or improve over time, unlike patients in clinical research settings, who typically progress to dementia. Within a prospective population-based study, we identified neuropsychological tests predicting improvement or worsening over one year in cognitively-driven everyday functioning as measured by Clinical Dementia Rating (CDR). Participants were 1682 adults aged 65+ and dementia-free at baseline. CDR change was modeled as a function of baseline test scores, adjusting for demographics. Among those with baseline CDR=0.5, 29.8% improved to CDR=0; they had significantly better baseline scores on most tests. In a stepwise multiple logistic regression model, tests which remained independently associated with subsequent CDR improvement were Category Fluency, a modified Token Test, and the sum of learning trials on Object Memory Evaluation. In contrast, only 7.1% with baseline CDR=0 worsened to CDR=0.5. They had significantly lower baseline scores on most tests. In multiple regression analyses, only the Mini-Mental State Exam, delayed memory for visual reproduction, and recall susceptible to proactive interference, were independently associated with CDR worsening. At the population level, changes in both directions are observable in functional status, with different neuropsychological measures predicting the direction of change.
Epidemiology; community; aging; Clinical Dementia Rating; cognition; prediction
Topiramate (TPM), a broad-spectrum antiepileptic drug, has been associated with neuropsychological impairment in patients with epilepsy and in healthy volunteers.
To establish whether TPM-induced neuropsychological impairment emerges in a dose-dependent fashion and whether early cognitive response (6-week) predicts later performance (24-week).
Computerized neuropsychological assessment was performed on 188 cognitively normal adults who completed a double-blind, placebo-controlled, parallel-group, 24-week, dose-ranging study which was designed primarily to assess TPM effects on weight. Target doses were 64, 96, 192, or 384 mg per day. The Computerized Neuropsychological Test Battery was administered at baseline and 6, 12, and 24 weeks. Individual cognitive change was established using reliable change index (RCI) analysis.
Neuropsychological effects emerged in a dose-dependent fashion in group analyses (p < 0.0001). RCI analyses showed a dose-related effect that emerged only at the higher dosing, with 12% (64 mg), 8% (96 mg), 15% (192 mg), and 35% (384 mg) of subjects demonstrating neuropsychological decline relative to 5% declining in the placebo group. Neuropsychological change assessed at 6 weeks significantly predicted individual RCI outcome at 24 weeks.
Neuropsychological impairment associated with TPM emerges in a dose-dependent fashion. Subjects more likely to demonstrate cognitive impairment after 24 weeks of treatment can be identified early on during treatment (i.e., within 6 weeks). RCI analysis provides a valuable approach to quantify individual neuropsychological risk.
Classification of evidence:
This study provides Class II evidence that TPM-induced cognitive impairment is dose-dependent with statistically significant effects at 192 mg/day (p < 0.01) and 384 mg/day (p < 0.0001).
There is ample evidence that physical and cognitive performance are related, but the results of studies investigating this relationship show great variability. Both physical performance and cognitive performance are constructs consisting of several subdomains, but it is presently unknown if the relationship between physical and cognitive performance depends on subdomain of either construct and whether gender and age moderate this relationship. The aim of this study is to identify the strongest physical predictors of cognitive performance, to determine the specificity of these predictors for various cognitive subdomains, and to examine gender and age as potential moderators of the relationship between physical and cognitive performance in a sample of community-dwelling older adults. In total, 98 men and 122 women (average age 74.0±5.6 years) were subjected to a series of performance-based physical fitness and neuropsychological tests. Muscle strength, balance, functional reach, and walking ability (combined score of walking speed and endurance) were considered to predict cognitive performance across several domains (i.e. memory, verbal attention, visual attention, set-shifting, visuo-motor attention, inhibition and intelligence). Results showed that muscle strength was a significant predictor of cognitive performance for men and women. Walking ability and balance were significant predictors of cognitive performance for men, whereas only walking ability was significant for women. We did not find a moderating effect of age, nor did we find support for a differential effect of the physical predictors across different cognitive subdomains. In summary, our results showed a significant relationship between cognitive and physical performance, with a moderating effect of gender.
Telephone interviews are widely used in geriatric settings to identify eligible research participants and to perform brief follow-up assessments of cognition. This article reports on the development and validation of the Memory and Aging Telephone Screen (MATS), a structured interview for older adults with mild cognitive impairment and/or significant memory complaints. We also developed three alternate forms of the MATS objective memory test to reduce practice effects engendered by multiple administrations.
Participants were enrolled in a longitudinal study that included 120 older adults with amnestic mild cognitive impairment (MCI), subjective cognitive complaints (CC) but without deficit on neuropsychological tests, and demographically-matched healthy controls (HC). An additional 15 patients with mild probable Alzheimer's disease (AD) completed the alternative forms study. All participants received the original MATS version, and a subset (n = 90) later received two of three alternate forms.
The MATS was sensitive to group differences and the alternate forms were equivalent. MATS objective memory test scores showed adequate stability over one year and were moderately correlated with scores on a widely used list-learning test (CVLT-II).
The MATS, a repeatable telephone screen that includes objective and subjective memory assessments, is useful for detecting individuals in the preclinical and early stages of dementia. Results encourage use of the MATS as a reliable and valid cognitive screening tool in research and clinical settings. Longitudinal assessments are being performed to investigate the predictive validity of the MATS for cognitive progression in MCI.
telephone screen; mild cognitive impairment; cognitive complaints; neuropsychological assessment; interview; memory
Z4032 is a randomized clinical trial conducted by the American College of Surgeons Oncology Group that compared sublobar resection alone (SR) to sublobar resection with brachytherapy (SRB) for high-risk operable patients with non-small cell lung cancer (NSCLC). This current report evaluate the early impact that adjuvant brachytherapy has on pulmonary function tests (PFT), dyspnea and perioperative (30-day) respiratory complications on this impaired patient population.
Eligible stage I NSCLC patients with tumors 3cm or less were randomized to SR or SRB. The outcomes measured included the % predicted forced expiratory volume (FEV1%), % predicted carbon monoxide diffusion capacity (DLCO%), dyspnea score using the UC San Diego Shortness of Breath Questionnaire. Pulmonary morbidity was assessed using the Common Terminology Criteria for Adverse Events (AE) Version 3.0 (CTCAE). Outcomes were measured at baseline, and at 3-months. A 10% change in PFT or a 10-point change in dyspnea score was deemed clinically meaningful.
Z4032 permanently closed to patient accrual in January 2010 with a total of 224 patients. At 3-month follow-up, PFT data is currently available on 148 (74 SR/74 SRB) patients described in this report. There were no differences in baseline characteristics between the arms. In the SR arm, 9 (12%) patients reported grade-3 respiratory AE compared to 12 (16%) in the SRB arm (p=0.49). There was no significant change in the percent change in DLCO%, or dyspnea score from baseline to 3-month within either arm. In the case of FEV1%, the percent change from baseline to 3-month was significant within SR arm (p=0.03), with patients reporting an improvement in the FEV1% at month 3. Multivariable regression analysis (adjusted for baseline values) showed no significant impact of treatment arm, tumor location (upper versus other lobe), or surgical approach (VATS versus thoracotomy) on the 3-month values for FEV1%, DLCO% and dyspnea scores. There was no significant difference in the incidence of clinically meaningful (10% PFT change, or 10-point dyspnea score) change between the two arms. Twenty-two percent of patients with lower lobe tumors compared to 9% with upper lobe tumors demonstrated a 10% decline in FEV1% (odds ratio 2.79; 95 CI=1.07 – 7.25; p=0.04).
Adjuvant intraoperative brachytherapy performed in conjunction with sublobar resection does not significantly worsen pulmonary function, or dyspnea at 3-months in a high-risk population with NSCLC. SRB was not associated with increased perioperative pulmonary AE. Lower-lobe resection was the only factor that was significantly associated with a clinically meaningful decline in FEV1%.
The CLOX is a clock drawing test used to screen for cognitive impairment in older adults, but there is limited normative data for this measure. This study presents normative data for the CLOX derived from a diverse sample of 585 community-dwelling older adults with complete cognitive data at baseline and 4-year follow-up. Participants with evidence of baseline impairment or substantial 4-year decline on the Mini-Mental State Examination were excluded from the normative sample. Spontaneous clock drawing (CLOX1) and copy (CLOX2) performances were stratified by age group and reading ability from the Wide Range Achievement Test, 3rd edition (WRAT-3). Lowest mean CLOX scores were observed for the oldest age group (75+ years old) with the lowest WRAT-3 reading scores. For all groups, average scores were higher for CLOX2 than CLOX1. These normative data may be helpful to clinicians and researchers for interpreting CLOX performance in older adults with diverse levels of reading ability.
Normative data; Clock drawing test; Reading ability; Older adults; Aging
Cognitive deterioration is a core symptom of many neuropsychiatric disorders and target of increasing significance for novel treatment strategies. Hence, its reliable capture in long-term follow-up studies is prerequisite for recording the natural course of diseases and for estimating potential benefits of therapeutic interventions. Since repeated neuropsychological testing is required for respective longitudinal study designs, occurrence, time pattern and magnitude of practice effects on cognition have to be understood first under healthy good-performance conditions to enable design optimization and result interpretation in disease trials.
Healthy adults (N = 36; 47.3 ± 12.0 years; mean IQ 127.0 ± 14.1; 58% males) completed 7 testing sessions, distributed asymmetrically from high to low frequency, over 1 year (baseline, weeks 2-3, 6, 9, months 3, 6, 12). The neuropsychological test battery covered 6 major cognitive domains by several well-established tests each.
Most tests exhibited a similar pattern upon repetition: (1) Clinically relevant practice effects during high-frequency testing until month 3 (Cohen's d 0.36-1.19), most pronounced early on, and (2) a performance plateau thereafter upon low-frequency testing. Few tests were non-susceptible to practice or limited by ceiling effects. Influence of confounding variables (age, IQ, personality) was minor.
Practice effects are prominent particularly in the early phase of high-frequency repetitive cognitive testing of healthy well-performing subjects. An optimal combination and timing of tests, as extractable from this study, will aid in controlling their impact. Moreover, normative data for serial testing may now be collected to assess normal learning curves as important comparative readout of pathological cognitive processes.
Serial assessments are commonplace in neuropsychological practice and used to document cognitive trajectory for many clinical conditions. However, true change scores may be distorted by measurement error, repeated exposure to the assessment instrument, or person variables. The present study provides reliable change indices (RCI) for the Boston Naming Test, derived from a sample of 844 cognitively normal adults aged 56 years and older. All participants were retested between 9 and 24 months after their baseline exam. Results showed that a 4-point decline during a 9–15 month retest period or a 6-point decline during a 16–24 month retest period represents reliable change. These cutoff values were further characterized as a function of a person’s age and family history of dementia. These findings may help clinicians and researchers to characterize with greater precision the temporal changes in confrontation naming ability.
BNT; RCI; Aging; Dementia; Serial; Assessment
Major Depressive Disorder (MDD) is a likely risk factor for dementia, but some cases of MDD in older adults may actually represent a prodrome of this condition. The purpose of this study was to use neuropsychological test scores to predict conversion to dementia in a sample of depressed older adults diagnosed as nondemented at time of neuropsychological testing.
Longitudinal, with mean follow-up of 5.45 years.
Outpatient depression treatment study at Duke University
30 nondemented individuals depressed at time of neuropsychological testing and later diagnosed with incident dementia; 149 nondemented individuals depressed at time of neuropsychological testing and a diagnosis of cognitively normal.
All participants received clinical assessment of depression, were assessed to rule out prevalent dementia at time of study enrollment, completed neuropsychological testing at time of study enrollment, and were diagnosed for cognitive disorders on an annual basis.
Non-demented, acutely depressed older adults who converted to dementia during the study period exhibited broadly lower cognitive performances at baseline than acutely depressed individuals who remained cognitively normal. Discriminant function analysis indicated that 2 neuropsychological tests, CERAD Recognition Memory and Trail Making B, best predicted dementia conversion.
Depressed older adults with cognitive deficits in the domains of memory and executive functions during acute depression are at higher risk for developing dementia. Some cases of late-life depression may reflect a prodrome of dementia in which clinical manifestation of mood changes may co-occur with emerging cognitive deficits.
geriatric depression; dementia; neuropsychology; memory; executive function
Theoretical models of cognitive aging are increasingly recognizing the importance of anxiety and depressive symptoms in predicting age-related cognitive changes and early dementia. This study examined the association between mild worry and depressive symptoms, and cognitive function in healthy, community-dwelling older adults.
A total of 263 healthy older adults participated in an observational prospective cohort study that assessed worry and depression symptoms, and a broad range of cognitive functions over a 2-year period.
Older adults with mildly elevated worry symptoms at baseline performed worse than older adults with minimal worry symptoms on measures of visual and paired associate learning. They were also more likely to show clinically significant (> 1.5 standard deviation) decline in visual learning and memory at a 2-year follow-up assessment (9.4% versus 2.5%; odds ratio = 3.8).
Assessment of worry symptoms, even mild levels, may have utility in predicting early cognitive decline in healthy, community-dwelling older adults.
Engagement in cognitively stimulating activities has been considered to maintain or strengthen cognitive skills, thereby minimizing age-related cognitive decline. While the idea that there may be a modifiable behavior that could lower risk for cognitive decline is appealing and potentially empowering for older adults, research findings have not consistently supported the beneficial effects of engaging in cognitively stimulating tasks. Using observational studies of naturalistic cognitive activities, we report a series of mixed effects models that include baseline and change in cognitive activity predicting cognitive outcomes over up to 21 years in four longitudinal studies of aging. Consistent evidence was found for cross-sectional relationships between level of cognitive activity and cognitive test performance. Baseline activity at an earlier age did not, however, predict rate of decline later in life, thus not supporting the concept that engaging in cognitive activity at an earlier point in time increases one's ability to mitigate future age-related cognitive decline. In contrast, change in activity was associated with relative change in cognitive performance. Results therefore suggest that change in cognitive activity from one's previous level has at least a transitory association with cognitive performance measured at the same point in time.
To determine the baseline prevalence of cognitive impairment in older men treated with ADT and to assess changes in cognitive performance over time.
Methods and results
Thirty-two patients (median age of 71 years, range 51–87) were administrated an extensive neuropsychological testing battery prior to ADT initiation, with 21 (65%) completing post-treatment evaluations 6 months later. At baseline, 45% scored >1.5 standard deviations below the mean on ≥2 neuropsychological measures. Using standardized inferential statistics, no change in cognition was documented following treatment. The Reliable Change Index revealed that, on a case-by-case basis, 38% demonstrated a decline in measures of executive functioning and 48% showed improvement on measures of visuospatial abilities. Within exploratory analyses, patients who scored below expectation at baseline displayed no change in cognition, while patients with average or better scores at baseline displayed improvements in visuospatial planning and timed tests of phonemic fluency.
We found a high prevalence of lower than expected cognitive performance among a sample of patients just starting ADT for prostate cancer. Assessment of baseline cognitive function should be taken into account for future research and to inform clinical management.
Cognition; Androgen deprivation; Prostate; Elderly
Human spatial navigation can be conceptualized as egocentric or exocentric, depending on the navigator’s perspective. While navigational impairment occurs in individuals with cognitive impairment, less is known about navigational abilities in non-demented older adults. Our objective was to develop tests of navigation and study their cognitive correlates in non-demented older adults.
We developed a Local Route Recall Test (LRRT) to examine egocentric navigation and a Floor Maze Test (FMT) to assess exocentric navigation in 127 older adults without dementia or amnestic Mild Cognitive Impairment. Factor analysis was used to reduce neuropsychological test scores to three cognitive factors representing Executive Function/Attention, Verbal Ability, and Memory. We examined relationships between navigational tests and cognitive function (using both cognitive factors and the highest loading individual test on each factor) in a series of regression analyses adjusted for demographic variables (age, sex, and education), medical illnesses, and gait velocity.
The tests were well-tolerated, easy to administer, and reliable in this non-demented and non-MCI sample. Egocentric skills on the LRRT were associated with Executive Function/Attention (B -0.650, 95% C.I. -0.139, -0.535) and Memory (B -0.518, 95% C.I. -0.063, -4.893) factors. Exocentric navigation on the FMT was related to Executive Function/Attention (B -8.542, 95% C.I. -13.357, -3.727).
Our tests appear to assess egocentric and exocentric navigation skills in cognitively-normal older adults, and these skills are associated with specific cognitive processes such as executive function and memory.
This study tested the hypotheses that older adults make less advantageous decisions than younger adults on the Iowa gambling task (IGT). Less advantageous decisions, as measured by the IGT, are characterized by choices that favor larger versus smaller immediate rewards, even though such choices may result in long-term negative consequences. The IGT, and measures of neuropsychological function, personality, and psychopathology were administered to 164 healthy adults 18–85 years of age. Older adults performed less advantageously on the IGT compared with younger adults. Additionally, a greater number of older adult’s IGT performances were classified as ‘impaired’ when compared to younger adults. Less advantageous decisions were associated with obsessive symptoms in older adults and with antisocial symptoms in younger adults. Performance on the IGT was positively associated with auditory working memory and psychomotor function in young adults, and in immediate memory in older adults.
decision-making; aging; cognition; gambling task; frontal lobe function; executive function