Prevalent depressive symptoms as a risk factor for conversion to mild cognitive impairment in an elderly Italian cohort

Establishment of a mild cognitive impairment risk model in middle-aged and older adults: a longitudinal study

BACKGROUND

Early identification individuals at high risk of mild cognitive impairment (MCI) is essential for prevention and intervention strategies of dementia, such as Alzheimer's disease. MCI prediction considering the interdependence of predictors in longitudinal data needs to be further explored. We aimed to employ machine learning (ML) to develop and verify a prediction model of MCI.

METHODS

In a longitudinal population-based cohort of China Health and Retirement Longitudinal Study (CHARLS), 8390 non-MCI participants were enrolled. The diagnosis of MCI was based on the aging-associated cognitive decline (AACD), and 13 factors (gender, education, marital status, residence, diabetes, hypertension, depression, hearing impairment, social isolation, physical activity, drinking status, body mass index and expenditure) were finally selected as predictors. We implemented a long short-term memory (LSTM) to predict the MCI risks in middle-aged and older adults within 7 years. The Receiver Operating Characteristic curve (ROC) and calibration curve were used to evaluate the performance of the model.

RESULTS

Through 7 years of follow-up, 1925 participants developed MCI. The model for all incident MCI achieved an AUC of 0.774, and its deployment to the participants followed 2, 4, and 7 years achieved results of 0.739, 0.747, and 0.750, respectively. The model was well-calibrated with predicted probabilities plotted against the observed proportions of cognitive impairment. Education level, gender, marital status, and depression contributed most to the prediction of MCI.

CONCLUSIONS

This model could be widely applied to medical institutions, even in the community, to identify middle-aged and older adults at high risk of MCI.

Modifiable risk factors for mild cognitive impairment among cognitively normal community-dwelling older adults: A systematic review and meta-analysis

Although numerous studies have investigated modifiable risk factors for mild cognitive impairment (MCI) among community-dwelling seniors, no meta-analysis has summarized these findings. Five databases were searched from January 1, 2000, to December 30, 2023. The protocol was registered with PROSPERO. Data were extracted and reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant meta-analyses of modifiable risk factors were performed. The evidence of each factor was assessed by the GRADE for cohort studies. Of 16,651 citations, 87 studies involving 225,584 community-dwelling seniors were included. Fourteen meta-analyses involving 20 studies with 44,199 participants were performed. The analyses revealed low-to-moderate-quality evidence supporting that diabetes, 2 or more comorbidities, anxiety, apathy, depressive symptoms, and physical frailty were risk factors for incident MCI in older adults. Conversely, hypertension, agitation, and irritability might not be risk factors. Additionally, moderate-quality evidence supports the protective effect of engaging in cognitive-demanding activities on the onset of MCI. Collectively, this study constitutes the first extensive compilation of evidence regarding the various risk factors for the development of MCI in older adults. Our findings hold significant potential to guide the formulation of prevention and management strategies to either prevent or potentially reverse the onset of MCI.

Risk assessment and stratification of mild cognitive impairment among the Chinese elderly: attention to modifiable risk factors

BACKGROUND

The early identification of individuals at risk of mild cognitive impairment (MCI) has major public health implications for Alzheimer's disease prevention.

OBJECTIVE

This study aims to develop and validate a risk assessment tool for MCI with a focus on modifiable factors and a suggested risk stratification strategy.

METHODS

Modifiable risk factors were selected from recent reviews, and risk scores were obtained from the literature or calculated based on the Rothman-Keller model. Simulated data of 10 000 subjects with the exposure rates of the selected factors were generated, and the risk stratifications were determined by the theoretical incidences of MCI. The performance of the tool was verified using cross-sectional and longitudinal datasets from a population-based Chinese elderly cohort.

RESULTS

Nine modifiable risk factors (social isolation, less education, hypertension, hyperlipidaemia, diabetes, smoking, drinking, physical inactivity and depression) were selected for the predictive model. The area under the curve (AUC) was 0.71 in the training set and 0.72 in the validation set for the cross-sectional dataset. The AUCs were 0.70 and 0.64 in the training and validation sets, respectively, for the longitudinal dataset. A combined risk score of 0.95 and 1.86 was used as the threshold to categorise MCI risk as 'low', 'moderate' and 'high'.

CONCLUSION

A risk assessment tool for MCI with appropriate accuracy was developed in this study, and risk stratification thresholds were also suggested. The tool might have significant public health implications for the primary prevention of MCI in elderly individuals in China.

Cognitive Performance Deficits Are Associated with Clinically Significant Depression Symptoms in Older US Adults

Accumulating research has described cognitive impairment in adults with depression, however, few studies have focused on this relationship during older adulthood. Our cross-sectional study investigated the association between cognitive function performance and clinically significant depression symptoms in older adults. We analysed the data from the 2011 to 2014 National Health and Nutrition Examination Survey on older (aged 60 years and above) US adults. Cognitive function was assessed as a composite score and on a test-by-test basis based on the Consortium to Establish a Registry for Alzheimer's Disease Word List Learning Test, the Word List Recall Test, and Intrusion Word Count Test, the Animal Fluency Test, and the Digit Symbol Substitution Test (DSST). Depression was defined as clinically significant depression symptoms based on the standard cut-off point of the Patient Health Questionnaire-9 (PHQ-9) score of 10 or greater. Adjusted-logistic regression analysis was employed using survey weights to examine the former relationships. Sociodemographic factors, in addition to medical history and status in terms of self-reported chronic illness and the incidence of stroke or memory-cognitive function loss, were considered as covariates. Among 1622 participants of a survey-weighted 860,400 US older adults, cognitive performance was associated with clinically significant depression symptoms (p = 0.003) after adjustment. Most prominently, older adults with significant cognitive deficits had approximately two and a half times (OR: 2.457 [1.219-4.953]) higher odds for a PHQ-9 score above threshold compared to those with the highest performance. Particularly, those with lowest DSST score had increased odds of almost four times (OR: 3.824 [1.069-13.678]). Efforts to decipher the underlying aetiology of these negative disparities may help create opportunities and interventions that could alleviate the risks from depression, cognitive impairment, and associated consequences in older adults at a population level.

Cognitive Function and Depressive Symptoms among Chinese Adults Aged 40 Years and Above: The Mediating Roles of IADL Disability and Life Satisfaction

The purpose of this study was to investigate the relationship between cognitive function and depressive symptoms among Chinese adults aged 40 years and above, as well as the series of multiple mediating effects of Instrument Activities of Daily Living disability and life satisfaction on this relationship. The data was obtained from the China Health and Retirement Longitudinal Study (CHARLS, 2013-2018), including 6466 adults aged 40 years and above. The mean age of the adults was 57.7 ± 8.5. The SPSS PROCESS macro program was conducted to examine the mediating effects. The results indicated that there was a significant association between cognitive function and depressive symptoms five years later (B = -0.1500, 95%CI: -0.1839, -0.1161), which could also be demonstrated through three mediation pathways: (1) the mediating pathway through IADL disability (B = -0.0247, 95%CI: -0.0332, -0.0171); (2) the mediating pathway through life satisfaction (B = 0.0046, 95%CI: 0.0000, 0.0094); and (3) the chain mediation pathway through IADL disability and life satisfaction (B = -0.0012, 95%CI: -0.0020, -0.0003). Both IADL disability and life satisfaction have been proven to be crucial mediators for the relationship between cognitive function and depressive symptoms five years later. It is necessary to improve individuals' cognitive function and reduce the negative impact of disability on them, which is important to enhance their life satisfaction and prevent depressive symptoms.

Differential and subtype-specific neuroimaging abnormalities in amnestic and nonamnestic mild cognitive impairment: A systematic review and meta-analysis

While mild cognitive impairment (MCI) has been classified into amnestic MCI (aMCI) and nonamnestic MCI (naMCI), the neuropathological bases of these two subtypes remain elusive. Here, we performed a systematic review and meta-analysis to determine the subtype specificity of neuroimaging abnormalities in MCI and to identify neural features that may differ between aMCI and naMCI. We synthesized 50 studies that used common neuroimaging modalities, including magnetic resonance imaging and positron emission tomography, to compare brain atrophy, white matter abnormalities, cortical thinning, cerebral hypometabolism, amyloid/tau deposition, or other features among aMCI, naMCI, and normal cognition. Compared with normal cognition, aMCI shows diverse neuroimaging abnormalities of large effect sizes. In contrast, naMCI exhibits restricted abnormalities of small effect sizes. Some features, including medial temporal lobe atrophy and white matter abnormalities, are shared by the two MCI subtypes. Overall, brain abnormalities are worse, if not similar, in aMCI than in naMCI. The only neuroimaging abnormality specific to aMCI is increased amyloid burden; no feature specific to naMCI was found. Taken together, our findings have elucidated the neuropathological changes that occur in aMCI and naMCI. Clarifying the neuroimaging profiles of aMCI and naMCI can improve the early identification, differentiation, and intervention of prodromal dementia.

Depression and bone loss as risk factors for cognitive decline: A systematic review and meta-analysis

BACKGROUND

Depression is linked to Alzheimer's disease (AD) but it is unclear whether depression is also associated with cognitive decline in the preclinical phase and mild cognitive impairment (MCI). Previous meta-analyses have only investigated AD as an outcome without accounting for individuals showing cognitive decline that does not meet the diagnostic criteria for AD. Other potentially modifiable risk factors such as bone loss have also been less explored and there remains uncertainty around their temporal relationship with cognitive decline.

AIMS

To conduct a systematic review and meta-analysis investigating depression and bone loss as risk factors for subsequent cognitive decline.

METHODS

A comprehensive search strategy was developed and applied using four databases; MEDLINE Complete, Embase, PsycINFO and CINAHL Complete. The pooled summary effects were estimated as odds ratios with 95% confidence intervals using a random-effects model. The study protocol was registered with PROSPERO (ID: CRD42020159369).

RESULTS

A total of 75 longitudinal cohort studies were identified for meta-analysis, of which 70 examined the impact of depression on cognitive decline and five examined the impact of bone loss. Prior exposure to depression was found to be associated with cognitive score reduction (OR 1.33 95% CI 1.17, 1.51), MCI incidence (OR 1.52 95% CI 1.28, 1.79) and AD incidence (OR 1.79 95% CI 1.46, 2.2). Bone loss was also associated with the incidence of AD (OR=1.81 95% CI 1.28, 2.55).

CONCLUSIONS

Overall, the results support the hypothesis that depression is associated with subsequent cognitive decline. Bone loss was also found to be associated with AD incidence; however, due to the small number of studies, the results should be viewed with caution.

The association between antidepressants use and development of cognitive impairment among older women diagnosed with breast cancer

PURPOSE

This study aimed to evaluate the association between the development of cognitive impairment and the use of antidepressants among older women with breast cancer.

METHODS

This retrospective cohort study used the United States National Cancer Institute's Surveillance, Epidemiology, and End Results-Medicare database to identify women who were 67 years old and older and had breast cancer between 2008 and 2013. Propensity scoring was used to account for confounding pre-treatment factors, and Cox proportional hazards modeling was used to examine the risk of developing cognitive impairment among patients based on whether they used antidepressants.

RESULTS

A total of 3174 women taking antidepressants (mean age 75.2 ± 6.4) were matched with 3174 women not taking antidepressants (mean age 75.4 ± 6.7). Antidepressant use was associated with a significantly increased risk of cognitive impairment (hazard ratio [HR]: 1.33, 95%; confidence interval [CI]: 1.18-1.48). Additionally, we found that older women without a history of depression or anxiety who use antidepressants have a higher risk of developing cognitive impairment than those who did not use antidepressants (HR: 1.53, 95%; CI: 1.34-1.75 and HR: 1.39, 95%; CI: 1.23-1.56, respectively). Subgroup analysis showed that the use of non-tricyclic antidepressants (TCAs) was associated with a higher risk of cognitive impairment.

CONCLUSION

We found that non-TCA antidepressant use in older women with breast cancer was associated with a higher risk of cognitive impairment. This association was also observed among older women without depression or anxiety who used antidepressants.

Neuropsychiatric symptoms as prognostic makers for the elderly with mild cognitive impairment: a meta-analysis

BACKGROUND

Although several neuropsychiatric symptoms (NPSs) have been demonstrated to have value in the prediction of the progression of mild cognitive impairment (MCI) to dementia, these symptoms are less studied for the prediction of the transition from normal cognition (NC) to MCI.

METHODS

Prospective cohort studies were included if they reported on at least one NPS at baseline and had MCI as the outcome.

RESULTS

We obtained 13 cohort studies with a total population of 33,066. Depression was the most common neuropsychiatric symptom and could significantly predict transition to MCI (RR = 1.49, 95% CI: 1.13-1.86). However, depression was more capable of predicting amnestic MCI (RR=1.43, 95% CI: 1.04-1.83) than non-aMCI (RR= 0.96, 95% CI 95% CI: 0.60-1.33). Subgroup analysis suggested that the association between depression and MCI changed with depression severity, depression criteria, apolipoprotein-E-adjusted status, age, the percentage of females, and follow-up times, but some data were too sparse for a reliable estimate. Regarding other NPSs, there were insufficient data to assess their effect on the development of MCI. However, apathy, anxiety, sleep disturbances, irritability, and agitation might be risk factors for the prediction of NC-MCI transition with strong predictive value.

CONCLUSIONS

Depression was associated with an approximately 1.5-fold sincreased risk of the progression to MCI in the population with normal cognition. Other NPSs with underlying predictive value deserve more attention.

Relationships between sleep quality, depressive symptoms and MCI diagnosis: A path analysis

BACKGROUND

This study examined the complex relationships between sleep quality, depressive symptoms, and cognitive decline in older adults. We hypothesised that older age, lower education and greater medical comorbidities would each be associated with increased mild cognitive impairment (MCI) diagnosis risk through indirect effects via poorer sleep quality, and greater depressive symptomology.

METHODS

540 adults 44 years and over were recruited at the Brain and Mind Centre, Sydney, Australia. Participants underwent comprehensive psychiatric, neuropsychological, and medical assessment. Subjective sleep quality, current depressive symptomatology, and current medical burden were assessed.

RESULTS

There were significant indirect effects of each of age, comorbidities and education, that operated via both sleep and depression. Younger age, greater comorbidities and fewer years' education each predicted greater chance of MCI diagnosis via poorer sleep and in turn higher depressive symptomatology. Additionally, there was a significant direct effect of older age on MCI.

LIMITATIONS

The current study is cross-sectional and cannot determine whether poorer sleep quality and greater depressive symptomatology precede or arise as a result of the onset of cognitive decline in later-life. A longitudinal design may allow further explication of these relationships.

CONCLUSIONS

Both sleep and depression are linked with cognitive decline in older adults, with sleep disturbance appearing to predict depressive symptoms. These findings have implications for the management of MCI. Both greater depression symptomatology and sleep disturbance were shown to predict the risk of MCI diagnosis, with this effect strongest in those that are younger. Improved early detection and treatment of sleep problems in older adults may help prevent depressive symptom manifestation or exacerbation, in turn potentially reducing the risk of subsequent cognitive decline.

Development of Alzheimer disease in old major depressive patients based upon their health status: A retrospective study in Taiwan

This study is conducted to investigate the association between major depressive disorder and the subsequent development of Alzheimer disease (AD) in elderly patients with different health statuses using Taiwan's National Health Insurance Research Database (NHIRD).A retrospective cohort study was performed on subjects over 65 years old from 2002 to 2006 using a random sampling from the 1 million beneficiaries enrolled in the NHI. Patients who were diagnosed with major depressive disorder were selected as the case group. Subjects in the control group were selected from elderly patients who did not have depression during the study period by matching age, sex, and index date of depression with subjects in the case group using a ratio of 1:4 (case:control). Both groups of patients were checked annually over a period of 7 years to observe whether they subsequently developed AD.A total of 1776 subjects were included in the case group while 7104 subjects were in the control group. After the follow-up period, 59 patients (3.3%) with depression developed AD while 96 patients (1.4%) without depression developed AD. The Kaplan-Meier curves showed that the incidence rate of AD in both groups varied significantly depending on different health statuses (log-rank P < .001). Results of the generalized estimating equation model found that patients with depression (hazard ratio [HR] = 1.898; 95% confidence interval [CI] = 1.451-2.438), very severe health status (HR = 1.630; 95% CI = 1.220-2.177), or artery diseases (HR = 1.692; 95% CI = 1.108-2.584) were at a higher risk of developing AD than other groups.The association between major depressive disorder and the later development of AD varied depending on the health statuses of elderly patients. Clinicians should exercise caution when diagnosing and treating underlying diseases in elderly depressed patients, and then attempt to improve their health status to reduce the incidence rate of subsequent AD development.

Late-life depression and cognitive function among older adults in the U.S.: The National Health and Nutrition Examination Survey, 2011-2014

Discrepancies exist on the associations of late-life depression with cognition, and synergistic effect of depression and diabetes on cognition among older adults was suggested in literature. We aimed to examine the associations of late-life depression with cognitive function in a representative sample of older adults in the U.S., and to examine the associations among individuals with diabetes. A total of 3101 adults aged 60 and above of the 2011-2014 National Health and Nutrition Examination Survey who completed measurements of depressive symptoms and diabetes were included in cross-sectional analyses. The 9-item Patient Health Questionnaire (PHQ-9) was used to measure depressive symptoms (including overall, somatic and cognitive). Clinically relevant depression (CRD) and clinically significant depression (CSD) were defined by cutoffs of PHQ-9. Domain-specific cognitive function was examined using Delayed Word Recall Test, Digit Symbol Substitution Test, and Animal Fluency Test for memory, executive function/processing speed, and language, respectively. Z scores were created for overall cognition and specific domains. Multivariable linear regression models were applied to examine the association of depressive symptoms and scale-defined depression with cognition z scores. The overall, somatic and cognitive depressive symptoms were associated with lower cognitive function among older adults. Both CRD (β = -0.20, 95% CI: -0.28, -0.12) and CSD (β = -0.56, 95% CI: -0.75, -0.37) were associated with lower cognition. A synergistic relationship was found between depression and diabetes on lower cognition. These results suggested that cognition among older adults may be modified by late-life depression, and older adults with both depression and diabetes may be particularly impacted on cognition.

Depressive symptoms in relation to clinical symptom onset of mild cognitive impairment

ABSTRACTObjective:There is increasing evidence of an association between depressive symptoms and mild cognitive impairment (MCI) in cross-sectional studies, but the longitudinal association between depressive symptoms and risk of MCI onset is less clear. The authors investigated whether baseline symptom severity of depression was predictive of time to onset of symptoms of MCI.

METHOD

These analyses included 300 participants from the BIOCARD study, a cohort of individuals who were cognitively normal at baseline (mean age = 57.4 years) and followed for up to 20 years (mean follow-up = 2.5 years). Depression symptom severity was measured using the Hamilton Depression Scale (HAM-D). The authors assessed the association between dichotomous and continuous HAM-D and time to onset of MCI within 7 years versus after 7 years from baseline (reflecting the mean time from baseline to onset of clinical symptoms in the cohort) using Cox regression models adjusted for gender, age, and education.

RESULTS

At baseline, subjects had a mean HAM-D score of 2.2 (SD = 2.8). Higher baseline HAM-D scores were associated with an increased risk of progression from normal cognition to clinical symptom onset ≤ 7 years from baseline (p = 0.043), but not with progression > 7 years from baseline (p = 0.194). These findings remained significant after adjustment for baseline cognition.

CONCLUSIONS

These results suggest that low levels of depressive symptoms may be predictive of clinical symptom onset within approximately 7 years among cognitively normal individuals and may be useful in identifying persons at risk for MCI due to Alzheimer's disease.

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.

Clinical characteristics and quality of life of older adults with cognitive impairment in Macao

BACKGROUND

Little is known about the characteristics of older adults with cognitive impairment in Macao. This study aimed to determine the prevalence of cognitive impairment and the quality of life (QOL) of older adults living in the community and nursing homes.

METHODS

A consecutive sample of 413 subjects (199 from the community; 214 from nursing homes) was recruited and interviewed using standardized instruments. Cognition was measured with the Repeatable Battery for the Assessment of Neuropsychological Status and QOL with the brief version of the World Health Organization Quality of Life instrument.

RESULTS

Altogether 87 subjects (21.0%) had cognitive impairment. On multivariate analyses, advanced age (P < 0.001, OR = 1.06, 95%CI: 1.03-1.1) and depressive symptoms (P = 0.03, OR = 1.07, 95%CI: 0.005-1.1) were positively associated with cognitive impairment. Married marital status (P = 0.01, OR = 0.3, 95%CI: 0.1-0.7) and higher education level (P < 0.001, OR = 0.1, 95%CI: 0.06-0.3) were negatively associated with cognitive impairment. After the confounders were controlled for, cognitive impairment was significantly associated with the lower psychological (F _(11,412) = 6.3, P = 0.01) and social relationship domains of QOL (F _(11,412) = 4.0, P = 0.04).

CONCLUSION

Cognitive impairment was found to be common in community-dwelling and nursing home resident older adults in Macao. Given cognitive impairment's negative impact on QOL, appropriate strategies should be implemented to improve access to treatment in this population.

Fruit and vegetable intake, physical activity, and depressive symptoms in the African American Health (AAH) study

BACKGROUND

Healthy diet and physical activity (PA) have been associated with reduced depressive symptoms, but few studies have examined them simultaneously in African Americans.

AIMS

To investigate fruit and vegetable intake (FVI) and PA as predictors of clinically-relevant levels of depressive symptoms (CRLDS) in African Americans.

METHODS

African American Health (AAH) is a population-based longitudinal study of African Americans in St. Louis, MO, who were born in 1936-1950 (inclusive) and empaneled in 2000-01 (wave 1). At wave 8, participants self-reported fruit and vegetable intake (FVI) and completed the Yale Physical Activity Scale. At both waves 8 and 10, the CES-D 11-item scale was used to identify those who met criteria for CRLDS. Sequential logistic regression modeling was used to examine the associations of components of FVI/PA with CRLDS, both cross-sectionally (n = 680, including imputed values) and longitudinally (n = 582, including imputed values). Modeling employed gender, age, perceived income adequacy, and education as potential confounders.

RESULTS

Cross-sectionally, vigorous PA, and leisurely walking PA, were independently associated with lower odds of CRLDS in all but the fifth model and green vegetables in all models. Longitudinally, green vegetables and interactions between the FVI summary score, the PA summary score, and other factors at wave 8 were most consistently associated with CRLDS at wave 10. In both cross-sectional and longitudinal models, the socioeconomic variables showed the strongest association as risk factors for CRLDS.

LIMITATIONS

Both FVI and PA were self-reported rather than observed, our cohort had limited geographic- and age-ranges, and confidence intervals for some results were broad.

CONCLUSIONS

Green vegetables, total FVI, and various aspects of PA showed protective effects regarding CRLDS. Therefore, the promotion of such lifestyles is likely to help prevent CRLDS in this population.

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.

Subjective memory complaints, mood and MCI: a follow-up study

OBJECTIVES

Subjective memory complaints (SMC) are common in older people and previous research has shown an association with mood problems, such as depression and anxiety. SMC form part of the criteria for many definitions of mild cognitive impairment (MCI), but there is controversy over whether they should be included as they may be related more strongly to mood than to objective cognitive impairment. This study aims to clarify the relationship between mood and SMC in people with MCI.

METHOD

This paper reports an analysis of data from the Medical Research Council Cognitive Function and Ageing study. Structured interviews were conducted with community-dwelling older people to assess a range of aspects of cognitive functioning and mood. Data from two time points approximately 24 months apart were used in this analysis. At baseline, participants without dementia or severe cognitive impairment were categorised into three groups according to cognitive status. Mood was investigated by assessing symptoms of anxiety and depression which were defined using a diagnostic algorithm. Associations were tested using logistic regression and chi square analyses.

RESULTS

A clear association was shown between SMC and mood, both cross-sectionally and over time. The relationship between our two competing definitions of MCI suggested that mood problems were more strongly related to the presence of SMC than objective cognitive impairment.

CONCLUSION

SMC may be a function of anxiety and depression rather than being related to objective cognitive function. This questions whether SMC should be included in definitions of MCI.

Frailty determinants in two long-term care settings: Assistant living facilities and home and community-based programs

There is limited knowledge on differences in frailty among residents in assisted living facilities (ALF) and home and community-based services (HCBS). This study used a retrospective cross-sectional design to compare frailty determinants in two long-term care settings. The HCBS setting had a greater proportion of positive responses to 9 of 14 frailty indicators. The ALF setting had a greater proportion to only 2 of the 14 frailty indicators. The finding that the HCBS setting had a significantly greater proportion of participants with positive frailty indicators as compared to the ALF setting suggests the degree of frailty risk is different by health care setting.

Vascular depression consensus report - a critical update

BACKGROUND

Vascular depression is regarded as a subtype of late-life depression characterized by a distinct clinical presentation and an association with cerebrovascular damage. Although the term is commonly used in research settings, widely accepted diagnostic criteria are lacking and vascular depression is absent from formal psychiatric manuals such as the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition - a fact that limits its use in clinical settings. Magnetic resonance imaging (MRI) techniques, showing a variety of cerebrovascular lesions, including extensive white matter hyperintensities, subcortical microvascular lesions, lacunes, and microinfarcts, in patients with late life depression, led to the introduction of the term "MRI-defined vascular depression".

DISCUSSION

This diagnosis, based on clinical and MRI findings, suggests that vascular lesions lead to depression by disruption of frontal-subcortical-limbic networks involved in mood regulation. However, despite multiple MRI approaches to shed light on the spatiotemporal structural changes associated with late life depression, the causal relationship between brain changes, related lesions, and late life depression remains controversial. While postmortem studies of elderly persons who died from suicide revealed lacunes, small vessel, and Alzheimer-related pathologies, recent autopsy data challenged the role of these lesions in the pathogenesis of vascular depression. Current data propose that the vascular depression connotation should be reserved for depressed older patients with vascular pathology and evident cerebral involvement. Based on current knowledge, the correlations between intra vitam neuroimaging findings and their postmortem validity as well as the role of peripheral markers of vascular disease in late life depression are discussed.

CONCLUSION

The multifold pathogenesis of vascular depression as a possible subtype of late life depression needs further elucidation. There is a need for correlative clinical, intra vitam structural and functional MRI as well as postmortem MRI and neuropathological studies in order to confirm the relationship between clinical symptomatology and changes in specific brain regions related to depression. To elucidate the causal relationship between regional vascular brain changes and vascular depression, animal models could be helpful. Current treatment options include a combination of vasoactive drugs and antidepressants, but the outcomes are still unsatisfying.

Serotonergic drugs for the treatment of neuropsychiatric symptoms in dementia

Behavioral and psychological symptoms of dementia (known also as neuropsychiatric symptoms) are essential features of Alzheimer's disease and related dementias. The near universal presence of neuropsychiatric symptoms in dementia (up to 90% of cases) has brought significant attention of clinicians and experts to the field. Non-pharmacological and pharmacological interventions are recommended for various types of neuropsychiatric symptoms. However, most pharmacological interventions for the treatment of behavioral and psychological symptoms of dementia are used off-label in many countries. Cognitive decline and neuropsychiatric symptoms can be linked to alterations in multiple neurotransmitter systems, so modification of abnormalities in specific systems may improve clinical status of patients with neuropsychiatric symptoms. Use of serotonergic compounds (novel particles acting on specific receptors and widely acting drugs) in the treatment of neuropsychiatric symptoms is reviewed.

[Risk of depression in 75 years or older persons, comprehensive geriatric assessment and associated factors in primary care: cross sectional study]

OBJECTIVES

To determine the prevalence of the risk of depression, major defining characteristics and factors associated with.

DESIGN

Sub-study of comprehensive geriatric assessment cross-study.

SETTING

Primary health center.

PARTICIPANTS

For an estimated 14% prevalence we need a sample of 288 people. From 3854, 290 people ≥75 years were selected. Excluding terminals, chemotherapy, recent surgery, temporary residence, mental retardation, serious psychiatric illness, or under home care.

MEASUREMENT

OUTCOME

risk of depression (≥2 points on the Goldberg depression subscale.

DEPENDENT VARIABLES

Sociodemographic and five study areas of the Comprehensive Geriatric Assessment: medical -comorbidity, polypharmacy, falls and hospital admissions-, functional -Up&Go Test, Lawton-Brody and Barthel Index-, nutritional -Mini Nutritional Assessment (MNA)-, mental-affective -Pfeiffer Questionnaire and Goldberg scale-, and social. Descriptive analysis and logistic regression.

RESULTS

We obtained 290 interviews, with 102 (35.1%) male and mean age of 79.4 years (SD:3.2). The prevalence of the risk of depression was 37.2%, 26.5% in men and 43.1% in women (p=0.005). Association of risk of depression is observed with arterial hypertension (OR:3.87 95% CI:1.61-9.34), cancer (OR:4.12 95%, CI:1.58-10.76), lack of leisure activity (OR:2.75 95%, CI:1.33-5.67), increase of anxiety scale (OR:1.87 95%, CI:1.57-2.22) and decrease in MNA (OR:0.78 95%, CI:0.68-0.9).

CONCLUSIONS

The prevalence of risk of depression is higher than expected, although overestimated until being confirmed with a diagnostic test. We appreciate new associations of comorbidity variables with risk of depression and corroborate other known. The studied factors that were associated with the risk of depression should be included in future studies of geriatric depression.

Antidepressant Use and Cognitive Decline: The Health and Retirement Study

BACKGROUND

Depression is associated with cognitive impairment and dementia, but whether treatment for depression with antidepressants reduces the risk for cognitive decline is unclear. We assessed the association between antidepressant use and cognitive decline over 6 years.

METHODS

Participants were 3714 adults aged 50 years or more who were enrolled in the nationally representative Health and Retirement Study and had self-reported antidepressant use. Depressive symptoms were assessed using the 8-item Center for Epidemiologic Studies Depression Scale. Cognitive function was assessed at 4 time points (2004, 2006, 2008, 2010) using a validated 27-point scale. Change in cognitive function over the 6-year follow-up period was examined using linear growth models, adjusted for demographics, depressive symptoms, comorbidities, functional limitations, and antidepressant anticholinergic activity load.

RESULTS

At baseline, cognitive function did not differ significantly between the 445 (12.1%) participants taking antidepressants and those not taking antidepressants (mean, 14.9%; 95% confidence interval, 14.3-15.4 vs mean, 15.1%; 95% confidence interval, 14.9-15.3). During the 6-year follow up period, cognition declined in both users and nonusers of antidepressants, ranging from -1.4 change in mean score in those with high depressive symptoms and taking antidepressants to -0.5 change in mean score in those with high depressive symptoms and not taking antidepressants. In adjusted models, cognition declined in people taking antidepressants at the same rate as those not taking antidepressants. Results remained consistent across different levels of baseline cognitive function, age, and duration of antidepressant use (prolonged vs short-term).

CONCLUSIONS

Antidepressant use did not modify the course of 6-year cognitive change in this nationally representative sample.

Cyr N, Lavretsky H. The patterns of cognitive and functional impairment in amnestic and non-amnestic mild cognitive impairment in geriatric depression

OBJECTIVES

Depressed older adults are at risk for the development of mild cognitive impairment (MCI), but few studies have characterized MCI subtypes in geriatric depression. The objective of this study was to identify the clinical patterns of MCI in late-life depression.

DESIGN

Baseline demographic, clinical, and neuropsychological test data collected as part of a randomized antidepressant trial for geriatric depression.

SETTING

UCLA-based outpatient clinic.

PARTICIPANTS

One hundred thirty-eight older adults with major depression.

MEASUREMENTS

A neuropsychological test battery and comprehensive evaluations of depression, apathy, quality of life, medical burden, and vascular risk factors.

RESULTS

Seventy-one participants (51%) had MCI and 67 (49%) were cognitively normal. Of subjects with MCI, 14 (20%) had amnestic MCI and 57 (80%) had non-amnestic MCI. Overall, patients with MCI had greater depression severity, poorer quality of life, and worse performance on the Mini-Mental State Exam than patients without MCI. Patients with non-amnestic MCI had significantly greater depression severity than patients without MCI. Across all subjects, depression severity correlated with impaired performance in language and visuospatial functioning.

CONCLUSION

Our findings suggest that MCI is associated with greater severity of depression, poorer quality of life, and worse global cognitive function. Overall, subtypes of MCI in geriatric depression differ in the patterns of functional impairment, which may require different therapeutic approaches.

Mild cognitive impairment: diagnosis, longitudinal course, and emerging treatments

Mild cognitive impairment (MCI) is widely regarded as the intermediate stage of cognitive impairment between the changes seen in normal cognitive aging and those associated with dementia. Elderly patients with MCI constitute a high-risk population for developing dementia, in particular Alzheimer's disease (AD). Although the core clinical criteria for MCI have remained largely unchanged, the operational definition of MCI has undergone several revisions over the course of the last decade and remains an evolving diagnosis. Prognostic implications of this diagnosis are becoming clearer with regard to the risk of progressive cognitive deterioration. Although patients with MCI may represent an optimal target population for pharmacological and non-pharmacological interventions, results from clinical trials have been mixed and an effective treatment remains elusive. This article provides a brief overview of the evolution of the concept of MCI and reviews current diagnostic criteria, the longitudinal course of the disorder, and current and emerging treatments for MCI.

Role of depression in predicting time to conversion to mild cognitive impairment

OBJECTIVE

To establish whether, in a cohort with normal cognition, severity of depressive symptoms at baseline was related to the time taken for conversion to mild cognitive impairment (MCI) and whether this interacted with other potential risk factors, including APOE ε4 status and demographic and cognitive variables.

METHODS

In a population-based cohort study, 126 cognitively normal subjects were assessed for depressive symptoms at baseline using the Geriatric Depression Scale (GDS) and were then followed over 20 years with regular cognitive assessments. The interval-censored accelerated failure time model was used to establish whether GDS and other factors, including APOE ε4 status, predicted the median time to development of MCI.

RESULTS

Fifty subjects developed MCI. In APOE ε4 noncarriers, the degree of depressive symptoms at baseline predicted the time to development of MCI: An increase in GDS of 1 standard deviation (3.85) was associated with shortening of the median time to conversion to MCI by 25.4% (p = 0.0024, z = -5.6). This relationship remained statistically significant after controlling for cognitive and other confounding variables. The relationship was not significant in APOE ε4 carriers.

CONCLUSION

Depressive symptoms (measured by GDS) predict time to conversion to MCI in cognitively normal people who do not carry the APOE ε4 allele. This may explain conflicting results of previous studies where APOE ε4 status was not taken into account when exploring the relationship between depression and MCI. It may also have a clinical application in helping to identify people at greater risk of developing MCI.

Cognitive dysfunction and greater visit-to-visit systolic blood pressure variability

OBJECTIVES

To determine whether variability in blood pressure (BP) is negatively associated with performance on cognitive testing.

DESIGN

Multinational, longitudinal, observational cohort study.

SETTING

The Alzheimer's Disease Neuroimaging Initiative study.

PARTICIPANTS

Individuals with a screening diagnosis of mild cognitive impairment or normal cognition (N=626).

MEASUREMENTS

Mean, variance, and maximum BP were calculated based on measures collected from screening to 36 months. Analysis of covariance models were used to determine the association between BP measures and cognitive scores at 36 months after adjusting for covariates.

RESULTS

Greater variability in systolic (P<.05) but not diastolic (P>.18) BP was associated with worse global (Modified Alzheimer's Disease Assessment Scale Cognitive Component and Clinical Dementia Rating sum of boxes) and executive (Trail-Making Test Part B, Animal Fluency, and Vegetable Fluency) function and episodic memory (Rey Auditory Verbal Learning Test Total Score).

CONCLUSION

There is a clinically significant association between greater systolic BP variability and greater cognitive dysfunction. These results should be verified in other well-characterized cohorts, and the neuroanatomical pathophysiology underlying the observed greater cognitive impairment should be further explored.

Late-life depression as a risk factor for mild cognitive impairment or Alzheimer's disease in 30 US Alzheimer's disease centers

Identification of potentially modifiable risk factors for cognitive deterioration is important. We conducted a prospective study of 5,607 subjects with normal cognition and 2,500 subjects with mild cognitive impairment (MCI) at 30 Alzheimer's Disease Centers in the Unites States between 2005 and 2011. Cox regression was used to determine whether depression predicted transition from normal to MCI, or MCI to Alzheimer's disease (AD). Over an average of 3.3 visits, 15% of normal subjects transitioned to MCI (62/1000 per year), while 38% of MCI subjects transitioned to AD (146/1000 per year). At baseline, 22% of participants had recent (within the last two years) depression defined by clinician judgment; 9% and 17% were depressed using the Geriatric Depression Scale (GDS score ≥5) and the Neuropsychiatric Inventory Questionnaire (NPI-Q), respectively. At baseline, depressed subjects performed significantly worse on cognitive tests. Those always depressed throughout follow-up had an increased risk for progression from normal to MCI (RR = 2.35; 95% CI 1.93-3.08) versus never depressed. Normal subjects, identified as depressed at first visit but subsequently improved, were found to have lower risk of progression (RR 1.40 (1.01-1.95)). The 'always depressed' had only a modest increased risk of progression from MCI to AD (RR = 1.21 (1.00-1.46). Results were similar using time-dependent variables for depression or when defining depression via the GDS or NPI-Q. We found no effect of earlier depression (>2 years past). The effect of recent depression did not differ by antidepressant treatment, APOE4 allele status, or type of MCI. In conclusion, late-life depression is a strong risk factor for normal subjects progressing to MCI.

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

OBJECTIVE

Depression might be a risk factor for dementia. However, little is known about the prevalence of depressive symptoms in mild cognitive impairment (MCI) and whether mood or motivation-related symptoms are predominant.

METHOD

A total of 767 non-demented community-dwelling adults aged 70-90 years completed a comprehensive assessment, including neuropsychological testing, and a past psychiatric/medical history interview. Depressive symptoms were assessed using the Geriatric Depression Scale (GDS) and Kessler Psychological Distress Scale (K10). Exploratory factor analysis was performed on the GDS and K10 to derive 'mood' and 'motivation' subscales.

RESULTS

A total of 290 participants were classified as having MCI and 468 as cognitively normal (CN). Participants with MCI reported more depressive symptoms, and more MCI participants met the cut-off for clinically significant symptoms, relative to CN participants. Those with amnestic MCI (aMCI), but not non-amnestic MCI, had more depressive symptoms and were more likely to meet the cut-off for clinically significant depressive symptoms, relative to CN participants. Participants with MCI reported more mood-related symptoms than CN participants, while there were no differences between groups on motivation-related symptoms.

CONCLUSION

Individuals with MCI, especially aMCI, endorse more depressive symptoms when compared with cognitively intact individuals. These findings highlight the importance of assessing and treating depressive symptoms in MCI.

Efficacy of cognitive rehabilitation therapies for mild cognitive impairment (MCI) in older adults: working toward a theoretical model and evidence-based interventions

To evaluate the efficacy of cognitive rehabilitation therapies (CRTs) for mild cognitive impairment (MCI). Our review revealed a need for evidence-based treatments for MCI and a lack of a theoretical rehabilitation model to guide the development and evaluation of these interventions. We have thus proposed a theoretical rehabilitation model of MCI that yields key intervention targets-cognitive compromise, functional compromise, neuropsychiatric symptoms, and modifiable risk and protective factors known to be associated with MCI and dementia. Our model additionally defines specific cognitive rehabilitation approaches that may directly or indirectly target key outcomes-restorative cognitive training, compensatory cognitive training, lifestyle interventions, and psychotherapeutic techniques. Fourteen randomized controlled trials met inclusion criteria and were reviewed. Studies markedly varied in terms of intervention approaches and selected outcome measures and were frequently hampered by design limitations. The bulk of the evidence suggested that CRTs can change targeted behaviors in individuals with MCI and that CRTs are associated with improvements in objective cognitive performance, but the pattern of effects on specific cognitive domains was inconsistent across studies. Other important outcomes (i.e., daily functioning, quality of life, neuropsychiatric symptom severity) were infrequently assessed across studies. Few studies evaluated long-term outcomes or the impact of CRTs on conversion rates from MCI to dementia or normal cognition. Overall, results from trials are promising but inconclusive. Additional well-designed and adequately powered trials are warranted and required before CRTs for MCI can be considered evidence-based.

Depressive symptoms in oldest-old women: risk of mild cognitive impairment and dementia

OBJECTIVES

Increasing evidence suggests that depression is a risk factor for cognitive impairment, but it is unclear if this is true among the oldest old. We determined whether elevated depressive symptoms predicted 5-year incident mild cognitive impairment (MCI) or dementia, and neuropsychological test performance among oldest-old women.

DESIGN

Prospective.

SETTING

Three study sites.

PARTICIPANTS

302 women ≥85 years (mean, 87 ± 2).

MEASUREMENTS

Depressive symptoms were measured with the 15-item Geriatric Depression Scale (GDS); scores of 6 or more indicated elevated symptoms. Five years later, participants completed neuropsychological testing and clinical cognitive status was adjudicated.

RESULTS

In analyses of MCI versus normal cognition, 70% of women with GDS score 6 or more at baseline developed MCI versus 37% with GDS score less than 6. After adjustment for age, education, alcohol, and benzodiazepine use, and study site, GDS score 6 or more remained independently associated with much greater likelihood of developing MCI (multivariable odds ratio [MOR] = 3.71, 95% confidence interval (CI): 1.30-10.59). In analyses of dementia versus normal cognition, 65% of women with GDS score 6 or more developed dementia compared with 37% of those with GDS score less than 6 (MOR = 3.15, 95% CI: 1.03-9.65). Only 19% of women with GDS score 6 or more had normal cognitive status 5 years later, compared with 46% of those with GDS score less than 6 (MOR = 0.28, 95% CI: 0.11-0.73). Women with elevated depressive symptoms had worse scores on tests of global cognition and working memory.

CONCLUSION

Elevated depressive symptoms are an important risk factor for cognitive disorders and lower cognitive performance among women living to their ninth and tenth decades.

A retrospective analysis of the sentence writing component of the Mini Mental State Examination: cognitive and affective aspects

BACKGROUND

One of the components of the Mini Mental State Examination (MMSE) is the request to write a sentence. We investigated the relationship between the characteristics of the written sentence of the MMSE and the cognitive and affective status of elderly patients.

METHODS

The characteristics of the sentence were compared to the total MMSE score, sociodemographic characteristics, tests evaluating cognition and affective status, and diagnoses.

RESULTS

The number of words was significantly associated with the degree of cognitive impairment, whereas the emotional polarity of sentences and concerns about health were associated with depression.

CONCLUSIONS

Characteristics of the MMSE sentence may provide important additional information regarding both cognition and affect when assessing older people.

The association between late-life depression, mild cognitive impairment and dementia: is inflammation the missing link?

Depression, mild cognitive impairment (MCI) and dementia are highly prevalent conditions that are increasing exponentially with similarly expanding social, medical and economic burdens. While there is a clear clinical connection between these three disorders, the mechanism of action that links them is less well understood. The lack of well-accepted biomarkers results in high levels of diagnostic subjectivity, which then greatly impacts research results when attempting to further explore their association. There is also a variety of clinical presentations of depressive syndromes, particularly in the elderly; each one may be associated with a different risk in the progression from MCI to different types of dementia. The diagnostic challenges, the importance of biomarkers and the discussion of inflammation as a possible link between depression, MCI and dementia are examined in this article.

Depressive symptoms, antidepressant use, and future cognitive health in postmenopausal women: the Women's Health Initiative Memory Study

BACKGROUND

Antidepressants are commonly prescribed medications in the elderly, but their relationship with incident mild cognitive impairment (MCI) and probable dementia is unknown.

METHODS

The study cohort included 6,998 cognitively healthy, postmenopausal women, aged 65-79 years, who were enrolled in a hormone therapy clinical trial and had baseline depressive symptoms and antidepressant use history assessments at enrollment, and at least one postbaseline cognitive measurement. Participants were followed annually and the follow-up averaged 7.5 years for MCI and probable dementia outcomes. A central adjudication committee classified the presence of MCI and probable dementia based on extensive neuropsychiatric examination.

RESULTS

Three hundred and eighty-three (5%) women were on antidepressants at baseline. Antidepressant use was associated with a 70% increased risk of MCI, after controlling for potential covariates including the degree of depressive symptom severity. Selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs) were both associated with MCI (SSRIs: hazard ratios (HR), 1.78 [95% CI, 1.01-3.13]; TCAs: HR, 1.78 [95% CI, 0.99-3.21]). Depressed users (HR, 2.44 [95% CI, 1.24-4.80]), non-depressed users (HR, 1.79 [95% CI, 1.13-2.85]), and depressed non-users (HR, 1.62 [95% CI, 1.13-2.32]) had increased risk of incident MCI. Similarly, all three groups had increased risk of either MCI or dementia, relative to the control cohort.

CONCLUSIONS

Antidepressant use and different levels of depression severity were associated with subsequent cognitive impairment in a large cohort of postmenopausal women. Future research should examine the role of antidepressants in the depression-dementia relationship and determine if antidepressants can prevent incident MCI and dementia in individuals with late-life depression subtypes with different levels of severity.

Lack of association between prior depressive episodes and cerebral [11C]PiB binding

Depressive symptoms are frequent in Alzheimer's disease (AD), but it is controversial whether depression is a risk factor for AD. This study measured for the first time cortical amyloid-β (Aβ) levels using [(11)C] Pittsburgh Compound B (PiB) positron emission tomography (PET) in a group of nondemented patients with prior depressive episodes. Twenty-eight elderly patients (mean age 61 years, range 51-75, 18 women) with onset of first depressive episode more than 6 years ago but now remitted from depression and 18 healthy subjects (mean age 61 years, range 50-76, 12 women) were included. All subjects were investigated with cognitive testing, 3T magnetic resonance imaging (MRI) and [(11)C]PiB high resolution research tomography (HRRT) positron emission tomography scan. There was no between-groups difference in [(11)C]PiB binding (p = 0.5) and no associations to number of depressive episodes, cognitive performance, or antidepressant treatment. Patients with late onset of depression had increased severity of white matter lesions (p = 0.04). In this study depressive episodes were not associated with increased levels of [(11)C]PiB. Thus, our results do not support the notion that depressive episodes previously in life are a risk factor for developing AD.

Smaller brain size likely in young adults (<40 years old) with depressive symptoms compared to healthy controls: a retrospective study

PURPOSE

The aim of this study was to determine whether the brain size of young patients with depressive symptoms is smaller than that of healthy controls using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We retrospectively evaluated brain size by calculating the ratio of the brain area to that of the skull (the brain-to-skull ratio) on routine MRI scans including the splenium of the corpus callosum obtained from 19 patients <40 years old with depressive symptoms in 2009. The controls were 12 healthy individuals <40 years old who underwent MRI for medical examinations.

RESULTS

The mean brain-to-skull ratio of the control group was 0.850 ± 0.022 (range 0.822-0.889), and that of the patient group was 0.819 ± 0.041 (range 0.756-0.878). An unpaired t-test showed a significant difference in the brain-to-skull ratios between these groups (P = 0.011). In particular, in 7 of the 19 patients with longer duration of illness and more severe symptoms, the brainto-skull ratio was 89%-92% of the mean ratio of the control group.

CONCLUSION

The brain size of young patients with depressive symptoms appears to be smaller than that of healthy controls.

Persistent depressive symptoms and cognitive function in late midlife: the Whitehall II study

OBJECTIVE

Depression has been widely linked to poor cognition and dementia in the elderly. However, comorbidity at older ages does not allow an assessment of the role of mental health as a risk factor for cognitive outcomes. We examined the association between depressive symptoms, measured 6 times over an 18-year period, and cognitive deficits in late midlife.

METHOD

Of the 10,308 participants in the Whitehall II study, 4,271 men and women (aged 35-55 years at baseline) were followed up for 18 years, during which depressive symptoms were assessed 6 times using the General Health Questionnaire depression subscale. The follow-up was from 1985-1988 to 2002-2004. Cognition was assessed at the most recent wave (2002-2004, mean age 61 years, range 50-74 years) using 6 tests: memory, reasoning, vocabulary, 2 tests of verbal fluency, and the MMSE (Mini Mental State Examination). Cognitive deficit was defined as MMSE score <28 and performance in the worst sex-specific quintile for the other tests.

RESULTS

History of depressive symptoms, once or more in the 6 times assessed, had a weak association with some of the cognitive tests. However, in analysis adjusted for sociodemographic variables, diabetes, coronary heart disease, hypertension, stroke, and antidepressant use, persistent depressive symptoms (4-6 times) were associated with cognitive deficits on all tests: memory (OR=1.91; 95% CI, 1.36-2.67), reasoning (OR=1.60; 95% CI, 1.15-2.20), vocabulary (OR=1.75; 95% CI, 1.27-2.41), phonemic fluency (OR=1.40; 95% CI, 1.00-1.94), semantic fluency (OR=1.68; 95% CI, 1.20-2.35), and the MMSE (OR=1.76; 95% CI, 1.25-2.50).

CONCLUSIONS

Our data show that depressive episodes tend to persist in some individuals, and these individuals are at a greater risk of cognitive deficits in late midlife.

Recurrent depressive symptoms and the incidence of dementia and mild cognitive impairment

OBJECTIVE

A history of depression has been linked to an increased dementia risk. This risk may be particularly high in recurrent depression due to repeated brain insult. We investigated whether there is a dose-dependent relationship between the number of episodes of elevated depressive symptoms (EDS) and the risk for mild cognitive impairment (MCI) and dementia.

METHODS

A total of 1,239 older adults from the Baltimore Longitudinal Study of Aging were followed for a median of 24.7 years. Diagnoses of MCI and dementia were made based on prospective data. Participants completed the Center for Epidemiologic Studies Depression Scale at 1- to 2-year intervals and were considered to have an EDS if their score was > or = 16. Kaplan-Meier survival curves, log-rank test for trend for survivor functions, and Cox proportional hazards models were conducted to examine the risk of MCI and dementia by number of EDS.

RESULTS

We observed a monotonic increase in risk for all-cause dementia and Alzheimer disease as a function of the number of EDS. Each episode was associated with a 14% increase in risk for all-cause dementia. Having 1 EDS conferred an 87%-92% increase in dementia risk, while having 2 or more episodes nearly doubled the risk. Recurrence of EDS did not increase the risk of incident MCI.

CONCLUSIONS

Our findings support the hypothesis that depression is a risk factor for dementia and suggest that recurrent depression is particularly pernicious. Preventing the recurrence of depression in older adults may prevent or delay the onset of dementia.

Cognitive impairment and depression among Chinese nonagenarians/centenarians

PURPOSE

In this study, we explored the association between cognitive impairment and depression in the very elderly using a sample aged 90-108 years.

METHODS

A cross-sectional study.

RESULTS

The sample included 682 unrelated Chinese nonagenarians/centenarians (67.25% women, mean age of 93.49 years). The mean depression score (measured with the brief 23-item Geriatrics Depression Scale-Chinese Edition was 8.45 (standard deviation [SD] = 3.30). The mean of cognitive function scores (measured with the 30-item Mini-Mental State Examination) was 15.54 (SD = 5.38). There was no significant difference in cognitive function scores between subjects with and without depression, and there was also no significant difference in depression scores between subjects with and without cognitive impairment. There was also no significant difference in the frequency of depression between subjects with and without cognitive impairment or in the frequency of cognitive impairment between subjects with and without depression. Both the odds ratio (OR) of depression (as a function of increased cognitive impairment) and the OR of cognitive impairment (as a function of increased depression) were found to be insignificant. Pearson Correlation also showed no significant correlation between depression scores and cognitive function scores.

CONCLUSIONS

In summary, we found that depression was not directly correlated with cognitive impairment in Chinese nonagenarians and centenarians.

A multiplicity of approaches to characterize geriatric depression and its outcomes

PURPOSE OF REVIEW

Research in geriatric depression has always had a multidisciplinary bent, particularly in methods used to characterize depression. Understanding diagnosis, psychiatric comorbidities, and course continues to be a goal of clinical researchers. Those interested in cognitive neuroscience and basic neuroscience have more recently trained their sights on late-life depression. This review identifies recent progress in the characterization of geriatric depression using a variety of methodologies.

RECENT FINDINGS

Depression in the elderly remains underdetected and underdiagnosed, particularly in nonmental health settings. Studies of the impact of psychiatric comorbidities and of the negative outcomes of depression in older adults demonstrate that geriatric depression is a serious medical condition that not only affects mood but can also lead to functional and cognitive decline. Advances in neuroimaging technology have demonstrated structural and functional changes in the brains of older depressed patients. With the advent of brain banks in neuropsychiatry, we are now seeing postmortem neuroanatomical studies that seek to extend findings from clinical practice and from neuroimaging research.

SUMMARY

Clinicians should become more aware of advances in detection of depression, the effect of psychiatric comorbidities, the poor mood and cognitive outcomes associated with late-life depression and should keep abreast of recent neuroimaging and neuroanatomical findings.

[Usefulness of cognitive plasticity evaluation in the differential diagnosis of cognitive impairment and depression-induced pseudo-dementia]

INTRODUCTION

A major challenge for gerontological research is to differentiate adequately between old adults with poor performance on cognitive tasks due to depression, and those who present cognitive impairment associated with dementia. In view of the fact that cognitive plasticity has already proved to be efficient in the diagnosis of age-associated cognitive impairment, mild cognitive impairment and dementia, the objective of this study is to investigate the possibility that it may also prove useful in the differential diagnosis of these two disorders.

MATERIALS AND METHODS

A total of 50 old adults participated in the study. These completed the Positions Test (PT) and the Auditory Verbal Learning Test of Learning Potential (AVLT-LP) as measures of cognitive plasticity. Participants also undertook the Spanish version of Mini Mental State (MEC), Life Satisfaction Questionnaire (LSQ) and Geriatric Depression Scale (GDS). Socio-demographic data were also collected.

RESULTS

With regard to cognitive plasticity, depressed old adults do not differ from those without depression. On the other hand, old adults with cognitive impairment present less cognitive plasticity than those without cognitive impairment.

CONCLUSION

Cognitive plasticity appears to be a relevant variable in the differentiation between old people with low cognitive performance due to depression and old people with cognitive impairment.

Change in cognitive functioning following acute antidepressant treatment in late-life depression

OBJECTIVE

Selective Serotonin Reuptake Inhibitors (SSRIs) are the most commonly prescribed medications for geriatric depression. The association of late-life depression and cognitive impairment has been well documented. However, there have been few placebo-controlled trials examining the impact of SSRIs on cognitive functioning.

DESIGN

Prepost neuropsychological (NP) data collected as part of an 8-week, double-blind, placebo-controlled trial of citalopram in depressed patients aged 75 years and older were used to examine change in cognitive functioning.

SETTING

University-affiliated outpatient psychiatry clinics.

PARTICIPANTS

One hundred seventy-four community-dwelling men and women aged 75 years or older with nonpsychotic unipolar depression.

MEASUREMENTS

NP assessments included mental status (Mini-Mental State Examination), psychomotor speed (Wechsler Adult Intelligence Scale-III Digit Symbol Subtest), reaction time (Choice Reaction Time), visual-spatial skill (Judgment of Line Orientation), executive functioning (Stroop Color/Word Test), and memory (Buschke Selective Reminding Test).

RESULTS

Differences in the pattern of change by treatment group depended on responder status. Citalopram nonresponders were the only group to decline on verbal learning and psychomotor speed. Citalopram responders showed significant improvement in visuospatial functioning, when compared with nonresponders in either condition, but their improvement was not greater than responders on placebo. Citalopram responders showed greater improvement on psychomotor speed than citalopram nonresponders, but their improvement was not greater than placebo responders or nonresponders.

CONCLUSIONS

Medication may have a deleterious effect on some aspects of cognition among patients aged 75 years and older who have not responded. This suggests that patients should not be maintained on a medication if they have not had an adequate response.

Depression, cognition, apolipoprotein e genotype: latent class approach to identifying subtype

OBJECTIVES

Possessing the epsilon4 allele of apolipoprotein E (APOE-epsilon4) genotype is associated with cognitive impairment in nondemented older adults. The authors hypothesized that they might find a subtype of depression related to impaired cognitive performance associated with the APOE-epsilon4 allele.

DESIGN

A survey conducted between 2001 and 2003 with APOE genotyping.

SETTING

Primary care offices in the Baltimore area.

PARTICIPANTS

The study sample consisted of 305 adults aged 65 or older with complete information on APOE genotyping and covariates.

MEASUREMENTS

The authors used the latent class model to classify respondents according to symptom criteria of American Psychiatric Association's Diagnostic and Statistical Manual as assessed in the Composite International Diagnostic Interview and the following four measures of cognitive function: the Mini-Mental State Exam, Hopkins Verbal Learning Test, Controlled Oral Word Association Test, and the Brief Test of Attention. The authors examined the relationship between class membership and APOE genotype.

RESULTS

The latent class model yielded three classes: a nondepressed class, a class with depressive symptoms and average cognitive functioning, and a class with depressive symptoms (particularly thoughts of death and suicide) and impaired cognitive functioning. Possessing at least one APOE-epsilon4 allele was not predictive of class membership.

CONCLUSION

A subgroup of elderly patients with depressive symptoms, cognitive impairment, and a high likelihood of experiencing thoughts of death or suicide may exist that may not be related to APOE-epsilon4. Subgroups of older patients with depressive symptoms may be important to identify because of the association with thoughts of death or suicide and cognitive impairment.

Psychological distress and risk for dementia

The concept of mild cognitive impairment (MCI) primarily emphasizes changes in individuals' mental abilities, but it has recently been suggested that neuropsychiatric symptoms should also be considered important factors in age-related neurodegeneration. Psychological distress, defined as a reaction of an individual to external and internal stresses, is characterized by a mixture of psychological symptoms. It also may be considered a neuropsychiatric symptom encompassing depression, anxiety, and apathy. This paper reviews and summarizes recent evidence and relevant issues regarding the presence of psychological distress in healthy older adults and MCI patients and its relationship to risk for developing dementia. Results presented in this review show that psychological distress and depressive, anxious, and apathetic symptoms can be present in MCI and may predict progression to dementia. This article also provides suggestions for future research.