State anxiety may not affect memory encoding, retrieval, or recognition in older adults with mood disorders

Abstract

<h3>Introduction</h3> State-level anxiety can have broad effects on cognition that are both beneficial (e.g., Yerkes-Dodson law) and detrimental. Data from functional brain imaging and physiological studies suggest state anxiety affects memory performance; however, findings have been inconsistent, and any effects likely depend on the specific memory process being examined (e.g., encoding, retrieval, and retention) and sample characteristics (e.g., age, clinical status). In this vein, few studies have examined how state anxiety affects memory in older adults, and even fewer have focused on patients with late life mood disorders. Moreover, the literature in this regard has produced inconsistent and sometimes conflicting findings, with some studies suggesting a detrimental impact on recall and others suggesting no effect or even modest benefit. Further investigation is needed to better understand how different memory processes might be impacted by state anxiety in older adults with mood disorders. This is an important target of investigation, as accounting for affective state is essential to ascertaining the clinical significance of memory deficits observed during neuropsychological evaluations of older adult psychiatric patients. Accordingly, the goal of the current study was to examine if and how state anxiety affects major memory processes in older adults with mood disorders. <h3>Methods</h3> We analyzed cross-sectional data from 44 older adults (25 female) ranging in age from 55-82 years (mean = 66.41 ± 6.65) with diagnoses of either major depressive disorder (n=21) or bipolar spectrum disorder (n=23) who were enrolled in the Geriatric Mood Disorders Database study at McLean Hospital. State anxiety and memory were measured using the Generalized Anxiety Disorder-7 Item Scale (GAD-7) and California Verbal Learning Test (CVLT-II), respectively. Outcomes variables from the CVLT-II corresponded to three major memory processes: Encoding/registration (trial 1-5 total recall), retrieval (long delay free recall), and storage/retention (recognition accuracy). A whole-group correlational analysis (Spearman rank order) was first performed to examine associations between GAD-7 score and each memory process in the entire sample. Linear regressions were then performed separately for each CVLT-II variable using group (depression vs bipolar), GAD-7 score (mean centered), and their interaction term as predictors to determine if the relationship between group and memory performance varied as a function of state-level anxiety. <h3>Results</h3> Groups did not differ in age, sex, or years of education, though a significant group difference was seen in GAD-7 total score [Depression: 4.43 ± 4.78, Bipolar: 8.39 ± 5.70; t(42) = -2.49, p = .017]. In the whole group analysis, no significant correlations were observed between GAD-7 score and any of the CVLT-II outcomes (all ps > .15). Despite the significant group difference in GAD-7 score, regression analyses did not show significant group x GAD-7 interactions on any of the CVLT-II outcomes, nor were there any significant main effects of group or GAD-7 score on those outcomes (all ps > .10). <h3>Conclusions</h3> The current results suggest that state-level anxiety may not affect memory encoding, retrieval, or recognition in older adults with mood disorders. However, it is important to note that the current study examined only one memory measure (CVLT-II), which limited our ability to detect potential effects of state anxiety on other forms of memory (e.g., visuospatial) and other cognitive domains (e.g., attention/executive function). Similarly, the GAD-7 is a relatively brief anxiety measure that focuses on a narrower range of self-reported symptoms. Future research in this area should employ a broader range of state anxiety measures, such as functional neuroimaging and physiological measures. While this study is also limited by a somewhat modest sample size, it is nonetheless a novel contribution to the literature given the paucity of research to date on the effect of state anxiety on memory in older adults with mood disorders. It is also important to note that while our results are not significant this could provide insight into the effect a diagnosis of a mood disorder might have on resilience in older adults. If we consider the emotional growth that comes with learning how to cope with a mood disorder for many years, we could potentially see an improved ability for older adults with mood disorders to cope with their anxiety symptoms compared to those who are more recently diagnosed. This potential emotional resilience may provide a protective buffer to the threat of anxiety's impact on memory. <h3>This research was funded by</h3> This study is funded by the Rogers Family Foundation.