Prevalence and characteristics of depression in mild cognitive impairment: the Sydney Memory and Ageing Study

Effects of physical activity and depressive symptoms on cognitive function in older adults: National Health and Nutrition Examination Survey

BACKGROUND & AIMS

Population aging is a growing phenomenon, with cognitive impairment becoming a prevalent issue among the elderly. This study aimed to investigate the impact of physical activity and depressive symptoms on cognitive function in older adults using a nationally representative data set of U.S. older adults aged ≥ 60 years.

METHODS

The study comprised 2713 participants aged ≥ 60 from the National Health and Nutrition Examination Survey 2011-2014. Participants were classified into two groups: Cognitive impairment and No-Cognitive impairment, determined by the results of the Digit Symbol Substitution Test (DSST). Physical activity (PA) was assessed using the Global Physical Activity questionnaire (GPAQ), while depressive symptoms were evaluated using the Patient Health Questionnaire (PHQ-9). Logistic regression analysis examined the relationship between physical activity, depressive symptoms and cognitive function.

RESULTS

Multifactorial logistic regression analysis showed that high levels of physical activity were found to be significantly associated with a lower risk of cognitive impairment compared to low levels of physical activity [OR = 0.789, 95% CI:0.632 ~ 0.986, P = 0.037]. On the other hand, the presence of major depressive symptoms was significantly associated with a higher risk of cognitive impairment compared to the absence of depressive symptoms [OR = 3.482, 95% CI: 2.278 ~ 5.324, P < 0.001]. Participants in the recreational physical activity group exhibited higher Cognitive scores (P < 0.001), indicating better cognitive functioning.

CONCLUSION

High levels of Physical activity were independently associated with a lower incident cognitive impairment. Additionally, the severity of depression was positively correlated with an increased risk of cognitive impairment.

Exploring the relationship between perceived loneliness and subjective cognitive decline in older individuals

OBJECTIVE

Loneliness has been associated to a greater risk of cognitive decline and dementia in older individuals. However, evidence on whether this association also exists for older individuals who complain of cognitive problems is limited. We conducted a survey to examine the association between subjective cognitive decline in the working memory domain, perceived loneliness, depression, anxiety, and stress in older individuals with different profiles.

METHODS

A total of 302 healthy, old individuals completed 3 questionnaires to assess subjective cognitive problems in attention, executive functions, storage, depression, anxiety, stress, and perceived loneliness.

RESULTS

We conducted a cluster analysis and 3 clusters of individuals with different profiles emerged. Individuals with greater subjective cognitive problems (cluster 1) in the attention and storage domains, reported higher perceived loneliness and stress but not depression. In contrast, individuals with the least subjective cognitive problems (cluster 3) in the storage domain, reported lower perceived loneliness.

CONCLUSIONS

Individuals with higher subjective cognitive decline also report higher levels of perceived loneliness but not more depression than their peers. However, this correlation is present only for individuals with mild subjective cognitive decline (cluster 2). The implications for future research and interventions are discussed.

The weight-adjusted-waist index and cognitive impairment among U.S. older adults: a population-based study

Objectives

Multiple research projects have provided evidence of the correlation between obesity and cognitive impairment. WWI, a novel metric for assessing obesity, has the potential to provide a more precise assessment of muscle and fat mass. This research aimed to investigate the association between WWI and cognitive functioning among elderly individuals residing in the United States.

Methods

This study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2014. Weighted multiple linear regression models, smoothed fitted curves, and generalized weighted models were employed to examine the associations between WWI and cognitive function in linear and nonlinear contexts.

Results

The study included a cohort of 2,764 adult volunteers aged 60 years and older, all with complete data. Upon controlling for all potential confounding variables, our analysis revealed statistically significant negative associations between WWI and the Digit Symbol Substitution Test (DSST) score. Specifically, for each 1-unit increase in WWI, there was a corresponding loss of 3.57 points in the DSST score [-3.57 (-4.31, -2.82)]. The negative correlations between WWI with CERAD total word recall [-0.63 (-0.85, -0.40)], CERAD delayed recall [-0.19 (-0.30, -0.07)], and AFT [-0.65 (-0.94, -0.37)] were significant only in partially adjusted models.

Conclusion

Higher WWI was associated with poorer cognitive function.

Apathy as a determinant of health behaviors in older adults: Implications for dementia risk reduction

INTRODUCTION

Long-term improvements in physical inactivity and other behavioral risk factors are integral to dementia risk reduction; however, sustained behavior change is challenging. Apathy, depression, and fatigue may impact engagement in health behaviors, but their presentation overlaps. This study investigates whether these symptoms are differentially associated with multiple health behaviors.

METHODS

In 1037 community-dwelling older adults without dementia (aged 70-90, 55% women), regression analyses examined apathy, depression, and fatigue as predictors of health behaviors (physical activity, diet, alcohol, smoking) and a behavioral risk index.

RESULTS

Apathy was associated with reduced physical activity and alcohol use, and one or multiple behavioral risk factors. No or inconsistent relations were found between depression or fatigue and health behaviors.

DISCUSSION

Apathy is relevant to multiple health behaviors and should be considered when designing health promotion for older adults, including interventions for dementia risk reduction. Findings highlight the importance of distinguishing apathy from comorbid symptoms.

Highlights

Novel theory-based perspective on behavioural risk factors for dementia.Higher apathy predicted less physical activity and alcohol use, and increased odds of lifestyle risk factors.Depressive symptoms were not associated with any health behavior.Apathy may be a determinant of multiple health behaviors in older adults, distinct from depression and fatigue.Considering apathy in precision prevention of dementia appears warranted.

Mild cognitive impairment is associated with passive suicidal ideation in older adults: A population-based study

OBJECTIVE

To investigate the association between MCI and passive/active suicidal ideation in a population-based sample of older adults.

METHOD

The sample included 916 participants without dementia acquired from the two population-based studies Prospective Population Study of Women (PPSW) and the H70-study. Cognitive status was assessed using a comprehensive neuropsychiatric examination and classified according to the Winblad et al. criteria: 182 participants were classified as cognitively intact, 448 had cognitive impairment but did not fulfill MCI criteria and 286 were diagnosed with MCI. Passive/active suicidal ideation was assessed using the Paykel questions.

RESULTS

Passive or active suicidal ideation (any level) was reported by 16.0% of those with MCI and 1.1% of those who were cognitively intact. MCI was associated with past year life-weariness (OR 18.32, 95% CI 2.44-137.75) and death wishes (OR 5.30, 95% CI 1.19-23.64) in regression models adjusted for covariates including major depression. Lifetime suicidal ideation was reported more frequently in MCI (35.7%) than in cognitively intact participants (14.8%). MCI was associated with lifetime life-weariness (OR 2.90, 95% CI 1.67-5.05). Among individuals with MCI, impairments in memory and visuospatial ability were associated with both past year and lifetime life-weariness.

CONCLUSION

Our findings suggest reports of past year as well as lifetime passive suicidal ideation to be more frequent among individuals with MCI compared to those cognitively intact, indicating that individuals with MCI may constitute a high-risk group for suicidal behavior.

The effect of Mild Cognitive Impairment (MCI) on psychological distress among older adults in Ukraine

OBJECTIVES

Understanding the negative consequences of Mild Cognitive Impairment (MCI) in Ukraine among a population who have collectively experienced difficult life events, provided the impetus for the current study which analyzed whether the perception of psychological distress differed among older adults with two types of MCI (amnestic MCI [aMCI] & nonamnestic MCI [naMCI]) compared to their cognitively intact peers.

METHOD

A sample of 132 older adults were selected from an outpatient regional hospital in Lviv, Ukraine and assigned into either an MCI or non-MCI control group. A demographic survey, and the Symptom Questionnaire (SQ) were administered to both groups.

RESULTS

Results of an ANOVA comparing the SQ sub-scales between the Ukrainian MCI and control groups were analyzed. A multiple hierarchical regression analysis assessed the predictive value of MoCA scores on the SQ sub-scales. Compared to adults in the MCI group, adults in the control group reported significantly lower rates of anxiety, somatic, depressive symptoms, and total psychological distress.

DISCUSSION

While the level of cognitive impairment was a significant predictor for each sub-type of distress, the explained variance was minimal suggesting that other factors also played a role. Reference was made to a similar MCI sample in the U.S. which had lower SQ psychological distress scores than the Ukraine sample, further suggesting possible environmental effects on symptoms. The importance of depression and anxiety screening and treatment for older adults with MCI was also discussed.

A systematic review and meta-analysis of the prevalence and correlation of mild cognitive impairment in sarcopenia

Sarcopenia is a progressive skeletal muscle disorder involving the loss of muscle mass and function, associated with an increased risk of disability and frailty. Though its prevalence in dementia has been studied, its occurrence in mild cognitive impairment (MCI) has not been well established. As MCI is often a prelude to dementia, our study aims to investigate the prevalence of MCI among individuals with sarcopenia and to also ascertain whether sarcopenia is independently associated with MCI. The Cochrane Library, PubMed, Ovid, Embase and Web of Science were systematically searched for articles on MCI and/or sarcopenia published from inception to 1 February 2022. We reviewed the available literature on the number of individuals with MCI and/or sarcopenia and calculated odds ratios (ORs) of sarcopenia in MCI and MCI in sarcopenia, respectively. Statistical analyses were performed using the meta package in Stata, Version 12.0. A total of 13 studies and 27 428 patients were included in our analysis. The pooled prevalence of MCI in participants with sarcopenia was 20.5% (95% confidence interval [CI]: 0.140-0.269) in a total sample of 2923 cases with a high level of heterogeneity (P < 0.001; I²  = 95.4%). The overall prevalence of sarcopenia with MCI was 9.1% (95% CI: 0.047-0.134, P < 0.001; I²  = 93.0%). For overall ORs, there were 23 364 subjects with a mean age of 73 years; the overall adjusted OR between MCI and sarcopenia was 1.46 (95% CI: 1.31-1.62). Slight heterogeneity in both adjusted ORs (P = 0.46; I²  = 0%) was noted across the studies. The prevalence of MCI is relatively high in patients with sarcopenia, and sarcopenia may be a risk factor for MCI.

Cognitive Impairment Mediates the Association between Dietary Inflammation and Depressive Symptoms in the Elderly

The underlying mechanism in both cognitive impairment and depression was chronic inflammation, which could be reflected by the dietary inflammatory index (DII). However, the effect of cognitive impairment on the association between DII and depression was not clear. Therefore, in this study, we hypothesized that cognitive impairment could mediate the association between dietary inflammation and depressive symptoms. A total of 2550 participants aged ≥60 from the National Health and Nutrition Examination Survey (NHANES) in 2011-2014 were involved in the serial, cross-sectional study. Proinflammatory and anti-inflammatory diets were measured by DII. Cognitive impairment was measured by four dimensions, CERAD-immediate, CERAN-delayed, animal fluency test, and DSST. Depressive symptoms were measured by PHQ-9 scores. We found that a proinflammatory diet and cognitive impairment were both risk factors for depressive symptoms. An interaction between an inflammatory diet and cognitive impairment was detected (P-interaction = 0.060). In addition, all four dimensions of cognition mediated the association between DII and depressive symptom scores. Part of the association between DII and depressive symptoms scores could be explained by different dimensions of cognitive function, and the proportion of mediation ranged from 10.0% to 36.7%. In conclusion, cognitive impairment levels partly mediated the association between DII and depressive symptoms.

Electrophysiological Evidence of Impaired Cognitive Reappraisal in Amnestic Mild Cognitive Impairment: An Event-related Potential Study

BACKGROUND

Emotion dysregulation symptoms are associated with higher conversion rates from MCI to dementia. Thus, understanding the neural mechanism underlying emotion regulation in people with MCI could provide useful information in early detection and intervention of MCI. This study investigated cognitive reappraisal, an emotion regulation strategy, in people with MCI using event-related potentials analysis.

METHODS

Late positive potential (LPP) was measured in 46 amnestic MCI subjects and 47 healthy elderly controls (HECs) as they viewed neutral and unpleasant images. All participants viewed a brief description of the upcoming image; neutral images were neutrally described (the Neut condition), and negative images were preceded with either more neutral/positive (the Rea condition) or more negative (the Neg condition) interpretations.

RESULTS

MCI subjects reduced their emotional intensity to a smaller extent than HEC subjects. For MCI subjects, the decreased level of emotional intensity was positively correlated with function in the verbal and executive domains. The reduced intensity (Rea - Neg) was also inversely correlated with the LPP difference (Rea - Neg) 3,600-5,000 ms after stimulus onset. Compared with HEC subjects, MCI subjects showed hypoactivation in the cuneus in the N2 time range (240-310 ms) and in the inferior parietal lobule and supramarginal gyrus in the 3,600-5,000 ms range.

CONCLUSION

These results suggest that MCI subjects failed to maintain the reappraisal of negative stimuli in the late time window, which contributed to a smaller success with reappraisal.

The complex burden of determining prevalence rates of mild cognitive impairment: A systematic review

Mild cognitive impairment (MCI) is a syndrome characterized by a decline in cognitive performance greater than expected for an individual's age and education level, but that does not interfere much with daily life activities. Establishing the prevalence of MCI is very important for both clinical and research fields. In fact, in a certain percentage of cases, MCI represents a prodromal condition for the development of dementia. Accordingly, it is important to identify the characteristics of MCI that allow us to predict the development of dementia. Also, initial detection of cognitive decline can allow the early implementation of prevention programs aimed at counteracting or slowing it down. To this end, it is important to have a clear picture of the prevalence of MCI and, consequently, of the diagnostic criteria used. According to these issues, this systematic review aims to analyze MCI prevalence, exploring the methods for diagnosing MCI that determine its prevalence. The review process was conducted according to the PRISMA statement. Three thousand one hundred twenty-one international articles were screened, and sixty-six were retained. In these studies, which involved 157,035 subjects, the prevalence of MCI ranged from 1.2 to 87%. The review results showed a large heterogeneity among studies due to differences in the subjects' recruitment, the diagnostic criteria, the assessed cognitive domains, and other methodological aspects that account for a higher range of MCI prevalence. This large heterogeneity prevents drawing any firm conclusion about the prevalence of MCI.

Exercise Training-Related Changes in Cortical Gray Matter Diffusivity and Cognitive Function in Mild Cognitive Impairment and Healthy Older Adults

Individuals with Mild Cognitive Impairment (MCI) are at an elevated risk of dementia and exhibit deficits in cognition and cortical gray matter (GM) volume, thickness, and microstructure. Meanwhile, exercise training appears to preserve brain function and macrostructure may help delay or prevent the onset of dementia in individuals with MCI. Yet, our understanding of the neurophysiological effects of exercise training in individuals with MCI remains limited. Recent work suggests that the measures of gray matter microstructure using diffusion imaging may be sensitive to early cognitive and neurophysiological changes in the aging brain. Therefore, this study is aimed to determine the effects of exercise training in cognition and cortical gray matter microstructure in individuals with MCI vs. cognitively healthy older adults. Fifteen MCI participants and 17 cognitively intact controls (HC) volunteered for a 12-week supervised walking intervention. Following the intervention, MCI and HC saw improvements in cardiorespiratory fitness, performance on Trial 1 of the Rey Auditory Verbal Learning Test (RAVLT), a measure of verbal memory, and the Controlled Oral Word Association Test (COWAT), a measure of verbal fluency. After controlling for age, a voxel-wise analysis of cortical gray matter diffusivity showed individuals with MCI exhibited greater increases in mean diffusivity (MD) in the left insular cortex than HC. This increase in MD was positively associated with improvements in COWAT performance. Additionally, after controlling for age, the voxel-wise analysis indicated a main effect of Time with both groups experiencing an increase in left insular and left and right cerebellar MD. Increases in left insular diffusivity were similarly found to be positively associated with improvements in COWAT performance in both groups, while increases in cerebellar MD were related to gains in episodic memory performance. These findings suggest that exercise training may be related to improvements in neural circuits that govern verbal fluency performance in older adults through the microstructural remodeling of cortical gray matter. Furthermore, changes in left insular cortex microstructure may be particularly relevant to improvements in verbal fluency among individuals diagnosed with MCI.

The Effect of Cognitive Impairment on the Prognosis of Major Depressive Disorder

The study recruited 168 patients diagnosed with major depressive disorder (MDD). The nine-item Patient Health Questionnaire (PHQ-9) and Perceived Deficits Questionnaire for Depression (PDQ-D) were lower and the Digit Symbol Substitution Test (DSST) was higher in the community volunteers than those in MDD patients. Depression-related scores (17-item Hamilton Depression Rating Scale [HAMD-17], Clinical Global Impressions-Severity of Illness Scale [CGI-S], and PHQ-9), functioning-related scores (Sheehan Disability Scale [SDS]), and Work Efficiency and Activity Damage-Specific Health Problems questionnaire work productivity loss were decreased, and the quality of life-related scores (European Quality of life-5 Dimensions [EQ-5D] utility score) were increased in the MDD patients. PDQ-D was decreased and DSST was increased with the increase of follow-up time. Linear regression indicated that cognitive symptoms (PDQ-D and DSST) improved more slowly than depressive symptoms (PHQ-9). At baseline, PDQ-D was related with functioning (SDS and work productivity loss). PDQ-D and DSST were related with EQ-5D utility score. In addition, at month 6, PDQ-D was related with functioning (SDS and work productivity loss) and EQ-5D utility score. Cognitive impairment might be a risk for MDD and MDD-related changes in the functioning and quality of life.

Internet-Based Cognitive Behavior Therapy Only for the Young? A Secondary Analysis of a Randomized Controlled Trial of Depression Treatment

BACKGROUND

Late-life depression is a major public health concern, driving the development of complementary treatment options. This study investigates the effectiveness and acceptability of internet-based Cognitive Behavioral Therapy (iCBT) in older individuals (60+ years) compared to younger age groups.

MATERIALS AND METHODS

Secondary analysis of a cluster-randomized controlled trial with 647 (18-82 years; mean 43.9) mild to moderately severe depressed primary care patients receiving either iCBT + treatment as usual (TAU) or TAU alone. Severity of depression was measured by the Beck Depression Inventory (BDI-II) at baseline, 6 weeks and 6 months. Intention-to-treat analysis in three age groups (18-39 years, n = 264; 40-59 years, n = 300; 60+ years, n = 83) was performed, using mixed-effects regression models to quantify treatment effect.

RESULTS

No age differences in the effectiveness of iCBT were found. Patients in the intervention group consistently showed a greater reduction in depression severity than controls in all three age groups and at both follow-ups. Effect sizes ranged from d = 0.30 (40-59 years, 6 weeks) to d = 1.91 (60+ years, 6 months). Uptake of the intervention was banded around 70% with no differences between age groups (χ² = 0.18, p = .915). The mean number of completed modules increased with age (χ² = 18.99, p = .040).

DISCUSSION

iCBT is equally effective in both younger and older individuals, thus providing a valuable complementary element of routine late-life depression care.

CLINICAL TRIAL REGISTRATION

DRKS-ID: DRKS00005075 https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00005075.

Depression, Anxiety, and Apathy in Mild Cognitive Impairment: Current Perspectives

Objective: Mild cognitive impairment (MCI) is an important risk state for dementia, particularly Alzheimer's disease (AD). Depression, anxiety, and apathy are commonly observed neuropsychiatric features in MCI, which have been linked to cognitive and functional decline in daily activities, as well as disease progression. Accordingly, the study's objective is to review the prevalence, neuropsychological characteristics, and conversion rates to dementia between MCI patients with and without depression, anxiety, and apathy. Methods: A PubMed search and critical review were performed relating to studies of MCI, depression, anxiety, and apathy. Results: MCI patients have a high prevalence of depression/anxiety/apathy; furthermore, patients with MCI and concomitant depression/anxiety/apathy have more pronounced cognitive deficits and progress more often to dementia than MCI patients without depression/anxiety/apathy. Conclusions and Implications: Depression, anxiety, and apathy are common in MCI and represent possible risk factors for cognitive decline and progression to dementia. Further studies are needed to better understand the role and neurobiology of depression, anxiety, and apathy in MCI.

Role of depressive symptoms in subjective memory complaint in older adults with mild cognitive impairment

AIMS

To explore the independent relationship between depressive symptoms and subjective memory complaint (SMC) amongst older adults with mild cognitive impairment (MCI) after adjusting for objective cognitive function and other important confounding factors.

BACKGROUND

subjective memory complaint is a core symptom of MCI and is often the primary reason for older adults with MCI to seek for medical help. Improving subjective memory amongst older adults with MCI is important to enhance their quality of life and potentially delay further cognitive decline. Depressive symptoms, which are highly prevalent neuropsychiatric symptoms amongst older adults with MCI, may be one of the reasons that affect an individual's self-perception of memory function. However, there is a dearth of studies to provide a thorough evaluation of the independent relationship between depressive symptoms and SMC amongst older adults with MCI.

DESIGN

A descriptive correlational study.

METHODS

A consecutive sample (N = 154) of adults aged over 60 years was recruited from a community healthcare centre between June and September 2016. MCI was detected using the Montreal Cognitive Assessment. Depressive symptoms and subjective memory were measured using the Geriatric Depression Scale and Memory Inventory for the Chinese, respectively. Hierarchical regression was performed to explore the relationship between SMC and depressive symptoms, with control over objective cognitive function, socio-demographic and health-related confounding factors.

RESULTS

After controlling objective cognitive function and other confounding factors, SMC was independently associated with depressive symptoms (standardised β = 0.336, p < .001). This psychological status even explained for a greater variance (R²  = 8.8%) for SMC compared with objective cognitive function (R²  = 2.4%).

CONCLUSION

subjective memory complaint was independently associated with depressive symptoms in older adults with MCI. Early detection and management of depressive symptoms are highly important amongst this clinical cohort.

IMPLICATIONS FOR PRACTICE

Early detection and prompt treatment of depressive symptoms is a highly prioritised care agenda in managing SMC in older adults with MCI.

State of the science on mild cognitive impairment (MCI)

Mild cognitive impairment (MCI) represents a transitional stage between healthy aging and dementia, and affects 10-15% of the population over the age of 65. The failure of drug trials in Alzheimer's disease (AD) treatment has shifted researchers' focus toward delaying progression from MCI to dementia, which would reduce the prevalence and costs of dementia profoundly. Diagnostic criteria for MCI increasingly emphasize the need for positive biomarkers to detect preclinical AD. The phenomenology of MCI comprises lower quality-of-life, greater symptoms of depression, and avoidant coping strategies including withdrawal from social engagement. Neurobiological features of MCI are hypoperfusion and hypometabolism in temporoparietal cortices, medial temporal lobe atrophy particularly in rhinal cortices, elevated tau and phosphorylated tau and decreased Aβ42 in cerebrospinal fluid, and brain Aβ42 deposition. Elevated tau can be identified in MCI, particularly in the entorhinal cortex, using positron emission tomography, and analysis of signal complexity using electroencephalography or magnetoencephalography holds promise as a biomarker. Assessment of MCI also relies on cognitive screening and neuropsychological assessment, but there is an urgent need for standardized cognitive tests to capitalize on recent discoveries in cognitive neuroscience that may lead to more sensitive measures of MCI. Cholinesterase inhibitors are frequently prescribed for MCI, despite the lack of evidence for their efficacy. Exercise and diet interventions hold promise for increasing reserve in MCI, and group psychoeducational programs teaching practical memory strategies appear effective. More work is needed to better understand the phenomenology and neurobiology of MCI, and how best to assess it and delay progression to dementia.

The Impact of Depression on the Development of Mild Cognitive Impairment over 3 Years of Follow-Up: A Population-Based Study

BACKGROUND/AIMS

In the absence of effective treatments for dementia, major efforts are being directed towards identifying the risk factors of the prodromal phase of the disease. We report the incidence rates of mild cognitive impairment (MCI) in a Spanish population sample and assess the effect of depression at baseline on incident MCI (or MCI subtypes) at a 3-year follow-up.

METHODS

A total of 1,642 participants (age ≥50 years) were examined as part of a Spanish nationally representative longitudinal study. MCI was defined as the presence of cognitive concerns, objective evidence of impairment in one or more cognitive domains, preservation of independence in functional abilities, and no dementia. Depression was assessed through an adaptation of the Composite International Diagnostic Interview (CIDI 3.0). Binary and multinomial logistic regression analyses were carried out to assess the associations.

RESULTS

The overall MCI incidence rate was 33.19 (95% CI = 26.02, 43.04) per 1,000 person-years. Depression at baseline predicted the onset of MCI at follow-up after controlling for sociodemographics, cognitive functioning, and other physical health conditions (OR = 2.79; 95% CI = 1.70, 4.59). The effect of baseline depression on incident MCI subtypes was as follows: amnestic MCI, OR = 3.81 (95% CI = 1.96, 7.43); nonamnestic MCI, OR = 2.03 (95% CI = 0.98, 4.21).

CONCLUSION

Depression significantly increases the risk for MCI. Targeting depression among those at risk for dementia may help delay or even prevent the onset of dementia.

Prevalence of Dementia, Depression, and Mild Cognitive Impairment in a Rural Area of the Island of Crete, Greece

The studies on the prevalence of dementia, depression, and mild cognitive impairment (MCI) in Greece are sparse and show major variations of prevalence depending on geographical areas, nutritional habits, and the way of living. The aim of this door-to-door study was to find the prevalence of dementia, depression, and MCI in a rural Greek population. Four hundred and forty-three individuals older than 61years following the application of specific criteria were diagnosed with: normal cognition, depression, MCI with and without depression, and dementia with and without depression. Four diagnostic methods were used, 2 of which included Mungas correction for age and education. After Mungas adjustment, the results were as follows-depression: 33.9%; MCI: 15.3%; MCI with depression: 8.6%; dementia: 2.0%; and dementia with depression: 7.2%. Dementia is less prevalent compared to global data and other Greek areas. Mild cognitive impairment is more prevalent than dementia. High percentages of depression may be related to low education.

Perceived loneliness and general cognitive status in community-dwelling older adults: the moderating influence of depression

The relationship between depression, loneliness, and cognitive functioning among the elderly is not well understood in the literature. In the present study, we tested the moderating influence of depressive symptoms on loneliness and cognitive functioning. We recruited 100 community-dwelling older adults in Hong Kong. Demographic information, perceived loneliness, depressed mood, and general cognitive status were assessed. Results indicated that married participants reported lower levels of perceived loneliness (t (96) = 2.26, p = .03). We found a significant moderating effect of depressive symptoms on the relationship between perceived loneliness and general cognitive status (B = -.05, p = .002). Perceived loneliness correlated negatively with general cognitive status only in participants with higher levels of depressed mood (B = -.16, p = .01). Together, these findings suggest that perceived loneliness combined with depressed mood is related to poorer general cognitive status in older adults. The implications of these findings are discussed.

Do attitudes towards persons with mental illness worsen during the course of life? An age-period-cohort analysis

OBJECTIVE

Cross-sectional studies frequently find higher age associated with negative attitudes towards persons with mental illness. We explore whether attitudes worsen over the life span, or follow a cohort pattern.

METHOD

Using data from three identical population surveys in Germany from 1990, 2001 and 2011 (combined sample n = 7835), we performed age-period-cohort analyses determining the association of age, time period and birth-cohort with social distance from a person with either depression (n = 3910) or schizophrenia (n = 3925), using linear and nonlinear partial least squares regression models.

RESULTS

Social distance increases with age, independent from cohort and period effects, cumulating to an increase of 2.4 (schizophrenia) and 2.3 (depression) on the 28 point social distance scale over the life span (youngest to oldest participant). We found a cohort effect in depression, but not schizophrenia, with decreasing social distance until 1970 and a slight increase in younger cohorts. Period effects were visible particularly in schizophrenia, with growing social distance over time.

CONCLUSION

Considering demographic change and the vulnerability of older persons to severe outcomes of mental illness such as suicide, the observed increase of negative attitudes over the life span seems highly relevant. We discuss the role of conservatism and preferences for agreeable social contacts in older age.

Psychosocial Risk Factors for Cognitive Decline in Late-Life Depression: Findings from the MTLD-III Study

Background

Cognitive impairment and depression frequently co-occur in late life. There remains a need to better characterize psychosocial risk factors of cognitive decline in older adults with depression. We hypothesized that certain psychosocial factors would be associated with higher risk of cognitive decline in individuals with late-life depression.

Methods

130 individuals aged ≥ 65 years who had achieved remission from a major depressive episode were randomized to donepezil or placebo and then closely followed for two years. Using Cox proportional hazard models, we examined the association between baseline median household income, education level, race, marital status, and social support and cognitive decline over the follow-up.

Results

Lower interpersonal support (OR = 0.86 [0.74–0.99], p = .04) and lower baseline global neuropsychological score (OR = 0.56 [0.36–0.87], p = .001) predicted shorter time to conversion to MCI or dementia in univariate models. These exposures did not remain significant in multivariate analyses. Neither socioeconomic status nor other psychosocial factors independently predicted cognitive diagnostic conversion (p > .05).

Conclusions

We did not find reliable associations between cognitive outcome and any of the psychosocial factors examined. Future large-scale, epidemiological studies, ideally using well-validated subjective measures, should better characterize psychosocial risk factors for cognitive decline in late-life depression.

Neurobiological correlates of depressive symptoms in people with subjective and mild cognitive impairment

OBJECTIVE

To test the hypothesis that depressive symptoms correlate with Alzheimer's disease (AD) type changes in CSF and structural and functional imaging including hippocampus volume, cortical thickness, white matter lesions, Diffusion tensor imaging (DTI), and fluoro-deoxy-glucose positron emission tomography (FDG-PET) in patient with subjective (SCI) and mild (MCI) cognitive impairment.

METHOD

In 60 patients, depressive symptoms were assessed using the Geriatric Depression Scale. The subjects underwent MRI, 18F-FDG PET imaging, and lumbar CSF extraction.

RESULTS

Subjects with depressive symptoms (n=24) did not have more pathological AD biomarkers than non-depressed. Uncorrected there were trends towards larger hippocampal volumes (P=0.06), less orbital WM damage measured by DTI (P=0.10), and higher orbital glucose metabolism (P=0.02) in the depressed group. The findings were similar when SCI and MCI were analyzed separately. Similarly, in patients with pathological CSF biomarkers (i.e., predementia AD, n=24), we found that correlations between scores on GDS and CSF Aß42 and P-tau indicated less severe AD-specific CSF changes with increasing depression.

CONCLUSION

Depressive symptoms are common in SCI/MCI, but are not associated with pathological imaging or CSF biomarkers of AD. Depression can explain cognitive impairment in SCI/MCI or add to cognitive impairment leading to an earlier clinical investigation in predementia AD.

Mild cognitive impairment diagnosed with the new DSM-5 criteria: prevalence and associations with non-cognitive psychopathology

OBJECTIVE

To contrast the prevalence of mild cognitive impairment (MCI) as diagnosed using DSM-5 criteria (DSM5-MCI) with MCI as diagnosed using Petersen's criteria (P-MCI) and to explore the association of both with non-cognitive psychopathological symptoms (NCPS).

METHOD

A two-phase epidemiological screening was implemented in a population-based sample of individuals aged 55+ (n = 4803). The Geriatric Mental State (GMS) was the main psychopathological instrument used, and AGECAT was used to make psychiatric diagnoses. Research psychiatrists diagnosed DSM5-MCI and P-MCI using operational criteria. Logistic regression models were then used to investigate the association of MCI with anxiety and depression and with NCPS.

RESULTS

Weighted prevalence of DSM5-MCI and P-MCI was, respectively, 3.72% and 7.93% for the aged 65+. NCPS were common in both MCI categories, but negative-type symptoms such as 'anergia' and 'observed slowness' were considerably more frequent among persons with DSM5-MCI. Anxiety and depression diagnostic categories were associated with both P-MCI and DSM5-MCI, but affective-type symptoms were mainly associated with P-MCI. Some negative-type symptoms were inversely associated with P-MCI, and no association was observed with DSM5-MCI.

CONCLUSION

The prevalence of DSM5-MCI was half that of P-MCI. Negative-type NCPS were more frequently and typically associated with DSM5-MCI.

Response to antidepressant medications in late-life depression across the spectrum of cognitive functioning

OBJECTIVE

Late-life depression frequently co-occurs with cognitive impairment. To inform clinical management of these conditions, we examined the hypotheses that, relative to cognitively normal elders meeting DSM-IV criteria for major depressive disorder, those with cognitive impairment would require greater intensity of pharmacotherapy to reach criteria for antidepressant response and would take longer to respond.

METHOD

Using data from the MTLD-3 study, we conducted a series of secondary analyses examining the implications of cognitive impairment for short-term, open-trial pharmacotherapy of late-life depression (major depressive disorder in individuals 65 years and older). The treatment algorithm consisted of 3 steps: initial treatment with a selective serotonin reuptake inhibitor (SSRI), a switch to a serotonin-norepinephrine reuptake inhibitor (SNRI) if the patient did not respond, and addition of an atypical antipsychotic if the patient did not respond to the SNRI. The first subject entered the protocol in April 2004, and the last subject exited in September 2009. We examined data for participants who completed the acute phase of MTLD-3 as responders and received a cognitive diagnosis (N = 153) based on National Alzheimer's Coordinating Center (NACC) Uniform Data Set criteria. We divided participants into 3 groups on the basis of NACC cognitive diagnosis: no cognitive disorder (n = 74), mild cognitive impairment (n = 60), and dementia (n = 19). For each group, we calculated the proportion of participants requiring first- (SSRI), second- (SNRI), or third-step (add-on atypical antipsychotic) treatment to meet criteria for response (17-Item Hamilton Depression Rating Scale score ≤ 10 for 3 consecutive weeks). We compared time to response across groups and correlates of nonresponse.

RESULTS

The 3 groups did not differ in intensity of pharmacotherapy (P = .68) or time to response (P = .84). Nonresponse was more strongly correlated with longer major depressive episode duration (P = .0015), presence of recurrent depression (P = .002), and younger current age (P = .047), rather than cognitive status (P = .61).

CONCLUSIONS

Cognitive status does not appear to impact short-term pharmacotherapy response variability in individuals whose depression responds to treatment with open-trial antidepressants delivered in a supportive, university-based medication clinic.

A hierarchy of predictors for dementia-free survival in old-age: results of the AgeCoDe study

OBJECTIVE

Progression from cognitive impairment (CI) to dementia is predicted by several factors, but their relative importance and interaction are unclear.

METHOD

We investigated numerous such factors in the AgeCoDe study, a longitudinal study of general practice patients aged 75+. We used recursive partitioning analysis (RPA) to identify hierarchical patterns of baseline covariates that predicted dementia-free survival.

RESULTS

Among 784 non-demented patients with CI, 157 (20.0%) developed dementia over a follow-up interval of 4.5 years. RPA showed that more severe cognitive compromise, revealed by a Mini-Mental State Examination (MMSE) score < 27.47, was the strongest predictor of imminent dementia. Dementia-free survival time was shortest (mean 2.4 years) in such low-scoring patients who also had impaired instrumental activities of daily living (iADL) and subjective memory impairment with related worry (SMI-w). Patients with identical characteristics but without SMI-w had an estimated mean dementia-free survival time of 3.8 years, which was still shorter than in patients who had subthreshold MMSE scores but intact iADL (4.2-5.2 years).

CONCLUSION

Hierarchical patterns of readily available covariates can predict dementia-free survival in older general practice patients with CI. Although less widely appreciated than other variables, iADL impairment appears to be an especially noteworthy predictor of progression to dementia.

Sydney Memory and Ageing Study: an epidemiological cohort study of brain ageing and dementia

Non-demented community-dwelling older adults aged 70-90 years (n = 1,037) randomly recruited from the electoral roll completed neuropsychological and medical assessments over six years. The overall prevalence of mild cognitive impairment (MCI) at baseline was 36.7%. Risk factors for MCI include APOE ε4 allele carrier status, high homocysteine, heart disease, poor odour identification, low visual acuity and low mental activity, but notable age and sex differences were observed. Neuropsychiatric symptoms were rare; depression was the most common and was associated with cognitive impairment in at least one domain as well as subsequent dementia 2 years later. Poorer cognitively demanding functional abilities were associated with cognitive impairment. Biomarkers for cognitive impairment and decline were identified. Inflammatory markers and plasma apolipoprotein levels were associated with poorer performance in the attention/processing speed domain. Measures of white matter lesions, white matter integrity, sulcal morphology and tractography were identified as novel biomarkers of early cognitive decline. Stronger deactivation in the posteromedial cortex with increasing memory load on functional MRI predicted future decline. Compared to previous reports, our prevalence rates of MCI were higher but rates of progression to dementia and reversion to normal were similar, as were risk factors for progression to dementia.

Behavioral symptoms related to cognitive impairment

Neuropsychiatric symptoms (NPS) are core features of Alzheimer's disease and related dementias. On one hand, behavioral symptoms in patients with mild cognitive impairment (MCI) can indicate an increased risk of progressing to dementia. On the other hand, mild behavioral impairment (MBI) in patients who usually have normal cognition indicates an increased risk of developing dementia. Whatever the cause, all dementias carry a high rate of NPI. These symptoms can be observed at any stage of the disease, may fluctuate over its course, are a leading cause of stress and overload for caregivers, and increase rates of hospitalization and early institutionalization for patients with dementia. The clinician should be able to promptly recognize NPI through the use of instruments capable of measuring their frequency and severity to support diagnosis, and to help monitor the treatment of behavioral symptoms. The aims of this review are to describe and update the construct 'MBI' and to revise the reported NPS related to prodromal stages of dementia (MCI and MBI) and dementia stages of Alzheimer's disease and frontotemporal lobar degeneration.