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Background:Individuals with mild cognitive impairment (MCI) commonly experience a number of sleep quality related issues. However, it remains unclear if these issues are specific to MCI or are simply attributed to the elevated levels depression and anxiety symptoms frequently observed among those with MCI. The present study sought to examine group differences between participants with MCI and matched controls on self-reported measures of sleep quality while controlling for depression and anxiety levels. Methods:Participants with MCI (N= 48) and demographically matched controls (N= 48) were administered with self-reported measures of anxiety, depression and sleep quality. Sleep quality between both groups were first analyzed using a Multivariate Analysis of Variance, and then subsequently a Multivariate Analysis of Covariance incorporating depression and anxiety scores as covariates. Results:The MCI group had significantly higher levels of depression and anxiety than the controls. On the sleep-related measures, the MCI group had significantly worse outcomes in sleep duration, disturbances, latency, efficiency, quality and daytime dysfunction. After controlling for depression and anxiety levels, with the exception of daytime dysfunction, all other differences remain significant, and are also associated with moderate to large effect sizes. Conclusion:The results suggest that sleep quality issues are present in MCI and are largely independent of depression and anxiety. [ABSTRACT FROM AUTHOR]

Despite the abundance of studies on asymmetries in manual laterality, a marker for atypical brain lateralization in depression and anxiety, findings in this area are mixed. Traditionally, research have looked at individual differences in depression and anxiety as a function of the direction of asymmetry. However, recent research has emphasized on studying the degree of asymmetry in addition to its direction. To these ends, the present study aims to unravel the associations between the degree and direction of manual lateralization, and depression/anxiety. Cognitively healthy elderlies (N = 326, 91 males,Mage = 68) were administered grip strength assessments on both hands and self-report measures of depression and anxiety. Partial correlation analyses controlling for age, education and sex revealed significant positive associations between degree of lateralization and anxiety in the overall sample and among right-dominant participants, as well as a significant positive relationship between degree of lateralization and depression among right-dominant participants. None of the correlations involving the direction of lateralization yielded significance, neither was there significant differences between left- and right-dominant participants on depression and anxiety scores. These findings suggest that the degree of manual lateralization, but not direction, is related to depression and anxiety at least among right-dominant individuals. [ABSTRACT FROM AUTHOR]

Objective: The co-occurrence of sleep problems, cognitive impairment, and depression among the elderly suggests that these three conditions are likely to be interrelated. Recent findings suggest that depressive symptoms moderate the relationship between sleep problems and cognitive impairment in elderly people but methodological problems have led to inconsistent conclusions. The present study aims to better understand the relationship between sleep quality, depressive symptoms, and cognitive function.Method: We administered the Repeatable Battery for the Assessment of Neuropsychological Status and self-report measures of sleep quality and depression to 380 elderly participants (Mage= 68 years,SD= 5.7). Bootstrapped moderation analyses were conducted to examine the role of depressive symptoms in the relationship between sleep and various aspects of cognitive function.Results: This moderation effect was significant in the domains of delayed memory (ΔR2= .01,F= 4.5,p= .04), language (ΔR2= .01,F= 4.6,p= .035), and general cognitive status (ΔR2= .01,F= 5.3,p= .02). However, unlike previous studies, higher sleep quality corresponded to better outcomes in delayed memory, language abilities, and general cognitive status in participants with low levels of depressive symptoms. No significant relationship between sleep quality and any cognitive function was observed among participants with high levels of depressive symptoms.Conclusions: Among individuals who reported low levels of depressive symptoms, sleep quality was positively related to cognitive performance in the domains of delayed recall, language, and general cognitive status. However, sleep quality was not significantly associated with cognitive abilities in these domains among participants with elevated levels of depressive symptoms; participants had relatively poor outcomes in these cognitive domains regardless of their sleep quality. [ABSTRACT FROM PUBLISHER]