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ObjectiveThe objective of this study is to determine whether differential item functioning (DIF) due to cognitive status impacted three depressive symptoms measures commonly used with older adults.MethodsDifferential item functioning in depressive symptoms was assessed among participants (N = 3558) taking part in four longitudinal studies of cognitive aging, using the Geriatric Depression Scale, the Montgomery-Åsberg Depression Rating Scale, and the Center for Epidemiologic Studies Depression Scale. Participants were grouped by cognitive status using a general cognitive performance score derived from each study's neuropsychological battery and linked to a national average using a population-based survey representative of the US population. The Clinical Dementia Rating score was used as an alternate grouping variable in three of the studies.ResultsAlthough statistically significant DIF based on cognitive status was found for some depressive symptom items (e.g., items related to memory complaints, appetite loss, lack of energy, and mood), the effect of item bias on the total score for each scale was negligible.ConclusionsThe depressive symptoms scales in these four studies measured depression in the same way, regardless of cognitive status. This may reduce concerns about using these depression measures in cognitive aging research, as relationships between depression and cognitive decline are unlikely to have been due to item bias, at least in the ways that were measured in the datasets we considered.

ObjectivePrevious studies have identified differential item function (DIF) in depressive symptoms measures, but the impact of DIF has been rarely reported. Given the critical importance of depressive symptoms assessment among older adults, we examined whether DIF due to demographic characteristics resulted in salient score changes in commonly used measures.MethodsFour longitudinal studies of cognitive aging provided a sample size of 3754 older adults and included individuals both with and without a clinical diagnosis of major depression. Each study administered at least one of the following measures: the Center for Epidemiologic Studies Depression scale (20-item ordinal response or 10-item dichotomous response versions), the Geriatric Depression Scale, and the Montgomery-Åsberg Depression Rating Scale. Hybrid logistic regression-item response theory methods were used to examine the presence and impact of DIF due to age, sex, race/ethnicity, and years of education on the depressive symptoms items.ResultsAlthough statistically significant DIF due to demographic factors was present on several items, its cumulative impact on depressive symptoms scores was practically negligible.ConclusionsThe findings support substantive meaningfulness of previously reported demographic differences in depressive symptoms among older adults, showing that these individual differences were unlikely to have resulted from item bias attributable to demographic characteristics we examined.

Background and Objectives Leisure activity engagement (LAE) may reduce the risk of incident dementia. However, cognitive performance may predict LAE change. We evaluated the temporal ordering of overall and subtypes of LAE (intellectual, physical, and social) and cognitive performance (global, language, memory, and visuospatial function) among non-demented older adults. Research Design and Methods The Washington Heights–Inwood Columbia Aging Project concurrently administered a survey measure of 13 leisure activities and a neuropsychological battery every 18–24 months for up to 14 years to 5,384 racially and ethnically diverse participants. We used parallel process conditional latent growth curve models to examine temporal ordering in the overall sample and within baseline diagnostic groups (mild cognitive impairment [MCI] vs. cognitively normal). Results Levels and changes of overall and subtypes of LAE were positively correlated with cognitive performance in the overall sample and within each diagnostic group. In the overall sample, higher initial memory was associated with slower declines in social LAE (estimate = 0.019, 95% confidence interval [95% CI]: 0.001–0.037). Among MCI, higher initial physical LAE was associated with slower declines in memory (estimate = 0.034, 95% CI: 0.001–0.067), but higher initial intellectual LAE was related to steeper declines in visuospatial function (estimate = −0.028, 95% CI: −0.052 to −0.004). Among cognitively normal, higher initial memory was associated with slower declines in intellectual LAE (estimate = 0.012, 95% CI: 0.002−0.022). Discussion and Implications Dynamic interplay of LAE with cognitive performance was observed across diagnostic groups. Levels of LAE subtypes could be more predictive of change in certain cognitive domains within older adults with MCI. [ABSTRACT FROM AUTHOR]

Abstract Background Interest in measuring functional status among nondisabled older adults has increased in recent years. This is, in part, due to the notion that adults identified as 'high risk' for functional decline portray a state that is potentially easier to reverse than overt disability. Assessing relatively healthy older adults with traditional self-report measures (activities of daily living) has proven difficult because these instruments were initially developed for institutionalised older adults. Perhaps less evident, are problems associated with change scores and the potential for 'construct under-representation', which reflects the exclusion of important features of the construct (e.g., disability). Furthermore, establishing a formal hierarchy of functional status tells more than the typical simple summation of functional loss, and may have predictive value to the clinician monitoring older adults: if the sequence task difficulty is accelerated or out of order it may indicate the need for interventions. Methods This review identified studies that employed item response theory (IRT) to examine or revise functional status scales. IRT can be used to transform the ordinal nature of functional status scales to interval level data, which serves to increase diagnostic precision and sensitivity to clinical change. Furthermore, IRT can be used to rank items unequivocally along a hierarchy based on difficulty. It should be noted that this review is not concerned with contrasting IRT with more traditional classical test theory methodology. Results A systematic search of four databases (PubMed, Embase, CINAHL, and PsychInfo) resulted in the review of 2,192 manuscripts. Of these manuscripts, twelve met our inclusion/exclusion requirements and thus were targeted for further inspection. Conclusions Manuscripts presented in this review appear to summarise gerontology's best efforts to improve construct validity and content validity (i.e., ceiling effects) for scales measuring the early stages of activity restriction in community-dwelling older adults. Several scales in this review were exceptional at reducing ceiling effects, reducing gaps in coverage along the construct, as well as establishing a formal hierarchy of functional decline. These instrument modifications make it plausible to detect minor changes in difficulty for IADL items positioned at the edge of the disability continuum, which can be used to signal the onset of progressive type disability in older adults.

Objective: Fatigue and cognitive dysfunction are major concerns for women with early-stage breast cancer during treatment and into survivorship. However, interrelationships of these phenomena and their temporal patterns over time are not well documented, thus limiting the strategies for symptom management interventions. In this study, changes in fatigue across treatment phases and the relationship among fatigue severity and its functional impact with objective cognitive performance were examined.Methods: Participants (N = 75) were assessed at five time points beginning prior to chemotherapy to 24 months after initial chemotherapy. Fatigue severity and impact were measured on the Brief Fatigue Inventory. Central nervous system (CNS) Vital Signs was used to measure performance based cognitive testing. Temporal changes in fatigue were examined, as well as the relationship between fatigue and cognitive performance, at each time point using linear mixed effect models.Results: Severity of fatigue varied as a function of phase of treatment. Fatigue severity and its functional impact were moderate at baseline, increased significantly during chemotherapy, and returned to near baseline levels by 2 years. At each time point, fatigue severity and impact were significantly associated with diminished processing speed and complex attention performance.Conclusions: A strong association between fatigue and objective cognitive performance suggests that they are likely functionally related. That cognitive deficits were evident at baseline, whereas fatigue was more chemotherapy dependent, implicates that two symptoms share some common bases but may differ in underlying mechanisms and severity over time. This knowledge provides a basis for introducing strategies for tailored symptom management that vary over time. [ABSTRACT FROM AUTHOR]

Objective: To develop a validated, caregiver-based measurement scale to assess sexual changes across several domains in a sample of 86 patients with penetrating traumatic brain injury (TBI) and 65 patients with neurodegeneration due to frontotemporal dementia and corticobasal syndrome. Methods: A new measure, the Sexual Symptoms in Neurological Illness and Injury Questionnaire (SNIQ), was constructed. Dimensionality, monotonicity, item discrimination power, and scalability were evaluated using nonparametric Mokken item response theory (IRT) methodology. Results: Three primary domains were established. The domains presented with sufficient reliability (rho.70 to.80), while meeting the Mokken IRT criteria of medium scalability. The domains were labeled ‘Prosocial sexual behaviour’ (H = .42), ‘Sexual interest’ (H = .50), and ‘Inappropriate sexual behaviour’ (H = .41). A fourth dimension emerged, ‘Detachment’ (H = .47), but with very few items. Conclusions: Construct validity was established for groups of items pertaining to three unique aspects of sexuality. These findings support further use of the SNIQ in assessing and researching sexual behaviours in patients with dementia and brain injury. [ABSTRACT FROM AUTHOR]

Objective: Age differences have been noted in the discrepancies between crystallized and fluid ability (Gc-Gf). Larger Gc-Gf discrepancies have also been shown to be associated with Alzheimer’s disease biomarkers and clinical severity. However, little is known regarding the relationship between Gc-Gf discrepancies in normal aging and functional outcomes. The aim of the present study was to examine this. Method: Data from 104 adults (Mage = 71.70 years, SD = 9.016) were included in the present study. Measures from the NIH toolbox were used to form the discrepancy scores. Physical, cognitive, and social activities were identified using the Community Healthy Activities Model Program for Seniors activity questionnaire. Linear regression analyses, controlling for age, education, gender, health, and depressive symptoms, were used to examine the association between social, cognitive, and physical activities on Gc-Gf discrepancies. Results: Results showed that social and physical activity were significantly associated with greater discrepancies between crystallized and fluid ability, independent of covariates. There was no association between cognitive activity and Gc-Gf discrepancies. Conclusions: Larger discrepancies between crystallized and fluid ability are related to frequency of social and physical activity. The findings support previous research that discrepancy scores may serve as a marker of cognitive decline. In more highly educated older individuals, Gc-Gf discrepancies may be a more accurate indicator of actual cognitive status. [ABSTRACT FROM AUTHOR]

Background: Decrements in instrumental activities (IADL) have been observed in the prodromal phase of dementia. Given the long predementia stage in neurodegenerative diseases, it has been proposed that subtle functional changes may precede clinical IADL impairment. Incorporating more challenging advanced ADLs (eg, volunteer work) into the assessment process may increase the sensitivity of functional measures, thus expanding the window for monitoring or interventions.Methods: Longitudinal cohort study was used (follow-ups, 18-24 month), with subjects aged 60 and older (n = 3,635). To elucidate the relationship between cognitive ability and functional status we employed an IADL scale with an extended range (ADL-extended; includes IADL but also more challenging advanced ADLs) that meets item response theory properties of dimensionality, monotonicity, and item hierarchy. Procedures involved (a) a dynamic change model employed to inspect the temporal relationship between ADL-extended and cognitive status and (b) Cox proportional hazards to assess the risk of incident dementia based on ADL-extended scores.Results: Growth curve modeling: baseline ADL-extended was significantly associated with all four cognitive domains investigated. Worse baseline ADL-extended was associated with more rapid declines in speed/executive function, and worse baseline memory was associated with more rapid declines in ADL-extended; a concurrent association was found for language and ADL-extended. Cox model: the risk of dementia was decreased for each additional ADL-extended item endorsed (hazard ratio [HR], 0.85; 95% confidence interval = 0.81-0.90).Conclusions: An increased risk of dementia could be observed in the ADL-extended items, which reflects an area of the functional continuum beyond IADL competencies. [ABSTRACT FROM AUTHOR]

Background and Purpose: The Medication Management Test (MMT) measures higher cognitive functioning. The aim of the analyses presented was to reduce assessment burden by developing a short-form version, and describe its psychometric properties. Methods: Factor analyses, item response theory (IRT), and differential item functioning (DIF) were performed to examine the dimensionality, reliability information, and measurement equivalence. Results: The ratio of the first two extracted eigenvalues from the exploratory principal component analysis was 7.62, indicating essential unidimensionality. Although one item "needs prompting for pill regime" evidenced DIF above the threshold for education and race/ethnicity, the magnitude was relatively small and the impact minimal. IRT-based reliability estimates were high (>0.80) across all subgroups. Conclusions: Because medication management is an important task associated with independent living, it is critical to assess whether medications can be self-administered safely. [ABSTRACT FROM AUTHOR]

Age is the strongest risk factor for physical disability and Alzheimer's disease (AD) and related dementias. As such, other aging-related risk factors are also shared by these two health conditions. However, clinical geriatrics and gerontology research has included cognition and depression in models of physical disability, with less attention to the pathophysiology of neurodegenerative disease. Similarly, AD research generally incorporates limited, if any, measures of physical function and mobility, and therefore often fails to consider the relevance of functional limitations in neurodegeneration. Accumulating evidence suggests that common pathways lead to physical disability and cognitive impairment, which jointly contribute to the aging phenotype. Collaborations between researchers focusing on the brain or body will be critical to developing, refining, and testing research paradigms emerging from a better understanding of the aging process and the interacting pathways contributing to both physical and cognitive disability. The National Institute of Aging sponsored a workshop to bring together the Claude D. Pepper Older Americans Independence Center and AD Center programs to explore areas of synergies between the research concerns of the two programs. This article summarizes the proceedings of the workshop and presents key gaps and research priorities at the intersection of AD and clinical aging research identified by the workshop participants. [ABSTRACT FROM AUTHOR]

Background/Aims: Dementia exhibits an insidious onset consisting of cognitive, behavioral, and functional impairment. We explored a functional continuum that extends assessment beyond the clinical instrumental activities of daily living (IADL) range and into advanced activities of daily living. Methods: We examined the predictive power (Cox regression; n = 2,471) of a unidimensional IADL-extended (IADL-x) scale for incident mild cognitive impairment (MCI). We also examined “time to MCI” as an outcome measure. Results: Each additional task endorsed on the IADL-x hierarchy (e.g., endorsing participation in 6 vs. 5 activities) resulted in a 10% reduction in MCI risk (HR 0.90, 95% CI 0.85–0.94, p < 0.001). For the fully adjusted model the risk reduction dropped to 6%. The odds of incident MCI within 2 years (for those below the median IADL-x total score) was 2.5 times higher (OR 2.60, 95% CI 1.52–4.4, p < 0.001) and 2 times higher for incident MCI within the next 5 years (OR 1.93, 95% CI 1.76–3.2, p < 0.01). Conclusion: The IADL-x metric appears to be a valid approach for determining the risk of MCI based on one’s position along a formal hierarchy of function. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether self-efficacy moderates the association between self-rated memory and depressive symptoms in a large sample of older adults. The influence of self-efficacy and depressive symptoms on memory performance was also examined in a subsample of individuals who reported poor memory.Methods: Non-demented participants (n = 3766) were selected from the 2012 wave of the Health and Retirement Study. Depressive symptomatology was assessed with the 8-item Center for Epidemiologic Studies Depression Scale. A modified version of the Midlife Developmental Inventory Questionnaire was used as the measure of self-efficacy. Participants were asked to rate their memory presently on a five-point scale from Excellent (1) to Poor (5). Immediate memory and delayed memory (after a 5-min interval) were measured by the number of correct words recalled from a 10-item word list.Results: Multiple regression analyses revealed that negative ratings of memory were significantly associated with greater levels of depressive symptoms, with this effect being greatest in those with low levels of self-efficacy. Additionally, greater self-efficacy was associated with optimal objective memory performances but only when depressive symptoms were low in individuals who reported poor memory function (n = 1196).Conclusion: Self-efficacy moderates the relationship between self-rated memory function and depressive symptoms. Higher self-efficacy may buffer against the impact of subjective memory difficulty on one's mood and thereby mitigating the effect of depressive symptoms on memory. Interventions should focus on increasing perceived self-efficacy in older adults reporting poor memory function to potentially minimize memory impairment. [ABSTRACT FROM AUTHOR]

As the population ages and dementia becomes a growing healthcare concern, it is increasingly important to identify targets for intervention to delay or attenuate cognitive decline. Research has shown that the most successful interventions aim at altering lifestyle factors. Thus, this study examined how involvement in physical, cognitive, and social activity is related to brain structure in older adults. Sixty-five adults (mean age=71.4 years, standard deviation=8.9) received the Community Healthy Activities Model Program for Seniors (CHAMPS), a questionnaire that polls everyday activities in which older adults may be involved, and also underwent structural magnetic resonance imaging. Stepwise regression with backward selection was used to predict weekly time spent in either social, cognitive, light physical, or heavy physical activity from the volume of one of the cortical or subcortical regions of interest (corrected by intracranial volume) as well as age, education, and gender as control variables. Regressions revealed that more time spent in cognitive activity was associated with greater volumes of all brain regions studied: total cortex (β=0.289, p=0.014), frontal (β=0.276, p=0.019), parietal (β=0.305, p=0.009), temporal (β=0.275, p=0.020), and occipital (β=0.256, p=0.030) lobes, and thalamus (β=0.310, p=0.010), caudate (β=0.233, p=0.049), hippocampus (β=0.286, p=0.017), and amygdala (β=0.336, p=0.004). These effects remained even after accounting for the positive association between cognitive activity and education. No other activity variable was associated with brain volumes. Results indicate that time spent in cognitively engaging activity is associated with greater cortical and subcortical brain volume. Findings suggest that interventions aimed at increasing levels of cognitive activity may delay cognitive consequences of aging and decrease the risk of developing dementia. [ABSTRACT FROM AUTHOR]

Previous research has shown that aging increases susceptibility to inattentional blindness (Graham and Burke, Psychol Aging 26:162, ) as well as individual differences in cognitive ability related to working memory and executive functions in separate studies. Therefore, the present study was conducted in an attempt to bridge a gap that involved investigating 'age-sensitive' cognitive abilities that may predict inattentional blindness in a sample of older adults. We investigated whether individual differences in general fluid intelligence and speed of processing would predict inattentional blindness in our sample of older adults. Thirty-six healthy older adults took part in the study. Using the inattentional blindness paradigm developed by Most et al. (Psychol Rev 112:217, ), we investigated whether rates of inattentional blindness could be predicted by participant's performance on the Raven's Advanced Progressive Matrices and a choice-reaction time task. A Mann-Whitney U test revealed that a higher score on the Raven's Advanced Progressive Matrices was significantly associated with lower incidences of inattentional blindness. However, a t test revealed that choice-reaction times were not significantly associated with inattentional blindness. Preliminary results from the present study suggest that individual differences in general fluid intelligence are predictive of inattentional blindness in older adults but not speed of processing. Moreover, our findings are consistent with previous studies that have suggested executive attention control may be the source of these individual differences. These findings also highlight the association between attention and general fluid intelligence and how it may impact environmental awareness. Future research would benefit from repeating these analyses in a larger sample and also including a younger comparison group. [ABSTRACT FROM AUTHOR]

Objective The present study aimed to investigate whether cognitive reserve moderated the association between depressive symptoms and cognition, as well as brain volumes in a sample of older adults. Methods Non-demented participants ( n = 3484) were selected from the Washington Heights/Hamilton Heights Inwood Columbia Aging Project (Northern Manhattan). A subsample of these participants without dementia ( n = 703), who had brain imaging data, was also selected for a separate analysis. Depressive symptomatology was assessed with the 10-item Center for Epidemiologic Studies Depression Scale. Reading level and years of education were used as measures of cognitive reserve. Four distinct cognitive composite scores were calculated: executive function, memory, visual-spatial, and language. Results Multiple regression analysis revealed interaction effects between both measures of cognitive reserve and depressive symptoms on all the cognitive outcome measures except for visual-spatial ability. Those with greater reserve showed greater cognitive decrements than those with lower levels of reserve as depressive symptoms increased. A borderline interaction effect was revealed between reading level and depressive symptoms on total brain volumes. Those with lower reading scores showed greater volume loss as depressive symptoms increased than those with higher reading scores. Conclusions Our findings indicate that the association between late-life depressive symptoms and core aspects of cognition varies depending on one's level of cognitive reserve. Those that had greater levels of education and/or reading ability showed a greater decrease in memory, executive, and language performances as depressive symptoms increased than those with lower years of education and reading ability. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Previous methods examining the Multiple Fatigue Inventory-20 (MFI-20) fatigue questionnaire have been limited to classical test theory, for example, factor analytic approaches. We employed modern test theory to further strengthen the construct validity of the MFI-20 fatigue in a sample of healthy late-midlife subjects. Five subdimensions of perceived fatigue were examined in n = 7,233 subjects: general fatigue, physical fatigue, reduced activity, reduced motivation, and mental fatigue. Fatigue burden was compared across age groups (aged 48-52 vs. 57-63) and gender. Mokken item response theory was used to investigate dimensionality, monotonicity, and invariant item ordering (IIO). In both age groups, as well as by gender, the Motivation domain presented with weak scalability, suggesting that caution be exercised when interpreting sum scores. For all groupings, the strongest scaling properties were observed in the General Fatigue domain. However, the General Fatigue domain did not meet the property of IIO. Two domains (for all groupings) did meet the minimum criteria for the property of IIO: Physical Fatigue and Activity. Introducing model parameters for items served to enhance the interpretive power of the MFI-20, allowing for the identification of the most optimal scales. Poorly performing items were more easily identified, and person ability was assessed more accurately. [ABSTRACT FROM PUBLISHER]

Background: As the number of adults in older age groups expands, difficulty performing usual activities of daily life is a rising health concern. A common exercise regimen employed to attenuate functional decline and disability has been resistance strength training. However, recent evidence suggests that functional tasks exercise may be more effective in preventing disability. Objective: Activities of Daily Living (ADL) measures are one of the most widely used tools in gerontology, and yet the full sensitivity of these instruments is often not realized. The purpose of this study is to enhance the interpretive power of ADL by formally confirming a hierarchy of decline, assessing discriminatory power, and examining option characteristic curves. Theoretically, a revised ADL instrument can improve the efficacy of functional tasks training programs. Methods: This was a cross-sectional study that employed Item Response Theory (IRT) to interpret ADL outcomes. Participants consisted of community-dwelling older adults (n = 548, aged 79) living in Scotland. Results: A Mokken scale with ρ = 0.77 was obtained, indicating good reliability, and satisfying the IRT assumption that a single unidimensional scale is present. The set H coefficient of 0.48 indicated that the scale may be ordered by decreasing difficulty, with the ‘Cut your own toe-nails?’ item being the most difficult and ‘Tie a good knot in a piece of string?’ being the least difficult. Discriminatory and option characteristic parameters revealed ‘Get on a bus?’ to be the task most closely related to the latent construct and that item options can be used to ascertain critical thresholds for prevention type strategies. Conclusions: Examining parameters relating to difficulty, discriminatory power, and option characteristics facilitated the identification of ADL/Instrumental ADL items that may serve to enhance functional task training in community-dwelling older adults. These analyses demonstrated that functional tasks have differing levels of discriminatory power, and that a task’s discriminatory power is likely to change with varying levels of disability. This observation reinforces the notion that exercises based on functional tasks may differ significantly in their therapeutic effect. Lastly, this study was able to highlight statistically meaningful cut-points relating to when older adults should begin ‘prehabilitation’ interventions. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Workshop on Synergies Between Alzheimer's Research and Clinical Gerontology and Geriatrics: Current Status and Future Directions" which appeared in a previous issue.

Background: Interest in measuring functional status among nondisabled older adults has increased in recent years. This is, in part, due to the notion that adults identified as 'high risk' for functional decline portray a state that is potentially easier to reverse than overt disability. Assessing relatively healthy older adults with traditional self-report measures (activities of daily living) has proven difficult because these instruments were initially developed for institutionalised older adults. Perhaps less evident, are problems associated with change scores and the potential for 'construct under-representation', which reflects the exclusion of important features of the construct (e.g., disability). Furthermore, establishing a formal hierarchy of functional status tells more than the typical simple summation of functional loss, and may have predictive value to the clinician monitoring older adults: if the sequence task difficulty is accelerated or out of order it may indicate the need for interventions.Methods: This review identified studies that employed item response theory (IRT) to examine or revise functional status scales. IRT can be used to transform the ordinal nature of functional status scales to interval level data, which serves to increase diagnostic precision and sensitivity to clinical change. Furthermore, IRT can be used to rank items unequivocally along a hierarchy based on difficulty. It should be noted that this review is not concerned with contrasting IRT with more traditional classical test theory methodology.Results: A systematic search of four databases (PubMed, Embase, CINAHL, and PsychInfo) resulted in the review of 2,192 manuscripts. Of these manuscripts, twelve met our inclusion/exclusion requirements and thus were targeted for further inspection.Conclusions: Manuscripts presented in this review appear to summarise gerontology's best efforts to improve construct validity and content validity (i.e., ceiling effects) for scales measuring the early stages of activity restriction in community-dwelling older adults. Several scales in this review were exceptional at reducing ceiling effects, reducing gaps in coverage along the construct, as well as establishing a formal hierarchy of functional decline. These instrument modifications make it plausible to detect minor changes in difficulty for IADL items positioned at the edge of the disability continuum, which can be used to signal the onset of progressive type disability in older adults. [ABSTRACT FROM AUTHOR]