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Objectives: In the United States, racial and ethnic disparities in memory dysfunction and Alzheimer disease are evident even after accounting for many risk factors. Psychological factors, such as psychological well-being, perceived control, depressive symptoms, and negative affect, may influence memory dysfunction, and associations may differ by race and ethnicity. This study examined whether psychological factors are differentially associated with episodic memory trajectories across racial and ethnic groups in the United States., Methods/design: The National Health and Aging Trends Study (NHATS), is a US-representative, longitudinal study of Medicare-eligible adults 65+ years old. Analyses of 5 years of data, included a total of 9411 participants without dementia at baseline. Adjusting for relevant covariates, a linear mixed model estimated the associations between psychological predictors and a composite of immediate and delayed trials from a word list memory test., Results: More depressive symptoms (B = -0.02), lower psychological well-being (B = 0.03), and lower perceived control (B = 0.05) were independently associated with lower initial memory. Depressive symptoms were associated with faster rate of memory decline (B = -0.01). Black (B = -0.34) and Hispanic (B = -0.28) participants evidenced lower initial memory level than whites, but only Hispanic (B = -0.04) participants evidenced faster memory decline than whites. There were no significant interactions between the psychological variables and race and ethnicity., Conclusions: Results extend previous studies showing racial and ethnic disparities in episodic memory trajectories, and the longitudinal effects of depressive symptoms on episodic memory in US samples. Epidemiological studies of cognitive aging should incorporate more psychological factors clarify cognitive decline and disparities., (© 2019 John Wiley & Sons, Ltd.)

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.)

Objective: Previous 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., Methods: Four 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., Results: Although statistically significant DIF due to demographic factors was present on several items, its cumulative impact on depressive symptoms scores was practically negligible., Conclusions: The 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., (Copyright © 2014 John Wiley & Sons, Ltd.)

Objective: Psychological symptoms are common in Parkinson's disease (PD). Psychological symptoms do not respond to psychotropic medications as well in patients with PD as in patients with psychiatric illnesses who do not have PD. Evidence that PD patients can be classified into distinct psychological symptom subgroups is conflicting. This study sought to examine potential psychological heterogeneity in PD with a broader range of instruments than has been used in previous studies., Methods: A comprehensive battery of psychological measures assessing dysphoria, apathy, anhedonia, anxiety, and negative affect was administered to 95 PD patients without global cognitive impairment. Latent class analysis was used to identify subgroups of patients based on continuous variables derived from the psychological battery. Multinomial regression was used to examine predictors of classification., Results: The latent class analysis identified three subgroups with incremental levels of psychopathology across most symptom domains. One exception was a greater level of affective flattening in the "psychologically healthy" group compared with the "moderate symptoms" group. Greater motor dysfunction and less education were associated with greater severity of psychological symptoms., Conclusions: These results support high psychological co-morbidity in PD, which complicates the treatment of individual symptoms. In addition, emotional blunting and anhedonia may be less indicative of widespread psychological distress than anxiety, dysphoria, and cognitive aspects of apathy. Clinicians should be aware that PD patients with greater motor dysfunction and less education are at greater risk not only for depression but also for a variety of other psychological symptoms that may not be routinely assessed., (Copyright © 2013 John Wiley & Sons, Ltd.)

Objective: Apathy and depression are the most common neuropsychiatric features in mild cognitive impairment (MCI). These syndromes have been linked to cognitive and functional decline. This study aimed to examine their unique relationships with specific cognitive abilities and daily functioning among MCI patients with memory impairment (amnestic MCI)., Methods: Data from 90 individuals referred for outpatient clinical neuropsychological evaluation and subsequently characterized as having amnestic MCI were obtained from a memory disorders center. MCI was defined using current NIA-Alzheimer's Association criteria. Variables included caregiver-reported apathy (Frontal Systems Behavior Scale) and depression (Memory and Behavioral Problems Checklist), scores on neuropsychological measures, and the Lawton-Brody Instrumental Activities of Daily Living Scale. Data were analyzed with multiple regressions controlling for age and education., Results: Depression was independently associated with composite scores of executive functioning. Neither apathy nor depression was associated with composite scores of attention, memory, or language. With regard to individual measures of executive functioning, depression was independently associated with poorer set-shifting (i.e., Trails B). Apathy was independently associated with poorer letter fluency (i.e., FAS). Apathy, but not depression, was associated with greater functional impairment., Conclusions: Apathy and depression are associated with different aspects of executive functioning in amnestic MCI, which may reflect differing patterns of frontal lobe pathology. Apathy exerts a greater impact on daily functioning than depression and may therefore increase reliance on caregivers. Results support the separability of apathy and depression in amnestic MCI. Clinicians should differentiate these neuropsychiatric states during assessment and treatment., (Copyright © 2012 John Wiley & Sons, Ltd.)