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Objective: This study sought to conduct a comprehensive search for genetic risk of cognitive decline in the context of geriatric depression. Design: A genome-wide association study (GWAS) analysis in the Neurocognitive Outcomes of Depression in the Elderly (NCODE) study. Setting: Longitudinal, naturalistic follow-up study. Participants: Older depressed adults, both outpatients and inpatients, receiving care at an academic medical center. Measurements: The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery was administered to the study participants at baseline and a minimum of twice within a subsequent 3-year period in order to measure cognitive decline. A GWAS analysis was conducted to identify genetic variation that is associated with baseline and change in the CERAD Total Score (CERAD-TS) in NCODE. Results: The GWAS of baseline CERAD-TS revealed a significant association with an intergenic single-nucleotide polymorphism (SNP) on chromosome 6, rs17662598, that surpassed adjustment for multiple testing (p = 3.7 × 10−7; false discovery rate q = 0.0371). For each additional G allele, average baseline CERAD-TS decreased by 8.656 points. The most significant SNP that lies within a gene was rs11666579 in SLC27A1 (p = 1.1 × 10−5). Each additional copy of the G allele was associated with an average decrease of baseline CERAD-TS of 4.829 points. SLC27A1 is involved with processing docosahexaenoic acid (DHA), an endogenous neuroprotective compound in the brain. Decreased levels of DHA have been associated with the development of Alzheimer's disease. The most significant SNP associated with CERAD-TS decline over time was rs73240021 in GRXCR1 (p = 1.1 × 10−6), a gene previously linked with deafness. However, none of the associations within genes survived adjustment for multiple testing. Conclusions: Our GWAS of cognitive function and decline among individuals with late-life depression (LLD) has identified promising candidate genes that, upon replication in other cohorts of LLD, may be potential biomarkers for cognitive decline and suggests DHA supplementation as a possible therapy of interest. [ABSTRACT FROM AUTHOR]

Background The ageing of the US labour force highlights the need to examine older adults' physical and psychological ability to work, under varying levels of occupational burnout. Aims To examine how age and burnout interact in predicting physical and psychological work ability. Methods Using a cohort of actively working nurses, we assessed factors on the Work Ability Index at 12-month follow-up and determined how these were related to age and exhaustion-related burnout at baseline. Results The study group consisted of 402 nurses aged 25-67 (mean = 41.7). Results indicated age by burnout interactions in which decrements in physical work ability with greater age were observed at all but the lowest level of burnout (1.5 SD below mean: β = -0.14, 95% CI -0.36, 0.07; 1 SD below: β = -0.23, 95% CI -0.39, -0.06; mean: β = -0.39, 95% CI -0.50, -0.29; 1 SD above: β = -0.56, 95% CI -0.70, -0.42; 1.5 SD above: β = -0.64, 95% CI -0.83, -0.46). In contrast, we observed decrements in psychological work ability with age at higher levels of burnout only (1 SD above: β = -0.20, 95% CI -0.35, -0.05; 1.5 SD above: β = -0.30, 95% CI -0.49, -0.11); at lower levels of burnout, older age was associated with improvements in this (1 SD below: β = 0.19, 95% CI 0.03, 0.35; 1.5 SD below: β = 0.29, 95% CI 0.08, 0.50). Conclusions Findings indicated physical and psychological dimensions of work ability that differed by age and occupational burnout. This emphasizes the need for interventions to reduce burnout and to address age-related strengths and vulnerabilities relating to physical and psychological work ability. [ABSTRACT FROM AUTHOR]

Objective The objective of the current study was to examine the relationship between the COMT Val158Met polymorphism and neuropsychological performance in depressed and nondepressed older adults. Methods One hundred and twenty-six clinically depressed older adults and 105 nondepressed comparison participants were compared on neuropsychological performance and COMT Val158Met (Val/Val, Val/Met, Met/Met). Results Based on multivariate regression models, the COMT Val158Met polymorphism was not associated with cognitive performance among depressed or nondepressed individuals, nor did this polymorphism account for the fact that depressed individuals performed worse than nondepressed individuals on several neuropsychological tests that are typically affected by depression. There was also no difference in frequency of the COMT Val158Met alleles between depressed and nondepressed individuals. Conclusions Although the current study found no association between COMT Val158Met polymorphism on a number of clinical neuropsychological tests that are typically found to be sensitive to depression, differential effects of the COMT Val158Met polymorphism on dopamine transmission in psychiatric and non-psychiatric populations may be further clarified by clinical research with neuroscience-based paradigms that segregate cognitive tasks into component processes with precise neural substrates, particularly with respect to the complex functions of the prefrontal cortex. Negative results can be important to narrowing down target processes and understanding the influence of clinical and demographic characteristics in studies of psychiatric genetics. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective The goal of the current study was to examine the neuropsychological profile of magnetic resonance imaging (MRI)-defined subcortical ischemic depression (SID). Methods Clinically depressed older adults with MRI-defined SID (n = 70) and depressed elders without SID (n = 75) were compared on neuropsychological performance, depression symptoms, and medical burden. Results Group comparisons revealed that the SID was associated with worse performance on all neuropsychological measures, but also with greater age, higher cardiac illness burden, and greater deficits in the depression symptoms of self-initiation and concentration. In multivariate regression models, auditory working memory and nonverbal memory remained worse among the SID group after controlling for contributions of age, cardiovascular risk, and depression symptoms. Conclusions Although auditory working memory span and nonverbal memory appear to be specifically associated with the ischemic pathology that defines SID, the typical individual with SID is also likely to have a broader profile of neuropsychological deficits than those without SID because they are typically older and have specific depression symptoms that predispose them to compromised neurocognitive performance. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article presents information on a study conducted on mild cognitive impairment without dementia among older adults in the U.S. It is mentioned that mild cognitive impairment might affect attention, language, judgment, and memory, but it doesn't severely impair activities of daily living. In the study, many neuropsychological tests were done on 856 people above 71 years. The researchers found that about 22% of the older people had cognitive impairment that did not develop into dementia.

Aim: To estimate the prevalence of Alzheimer's disease (AD) and other dementias in the USA using a nationally representative sample., Methods: The Aging, Demographics, and Memory Study sample was composed of 856 individuals aged 71 years and older from the nationally representative Health and Retirement Study (HRS) who were evaluated for dementia using a comprehensive in-home assessment. An expert consensus panel used this information to assign a diagnosis of normal cognition, cognitive impairment but not demented, or dementia (and dementia subtype). Using sampling weights derived from the HRS, we estimated the national prevalence of dementia, AD and vascular dementia by age and gender., Results: The prevalence of dementia among individuals aged 71 and older was 13.9%, comprising about 3.4 million individuals in the USA in 2002. The corresponding values for AD were 9.7% and 2.4 million individuals. Dementia prevalence increased with age, from 5.0% of those aged 71-79 years to 37.4% of those aged 90 and older., Conclusions: Dementia prevalence estimates from this first nationally representative population-based study of dementia in the USA to include subjects from all regions of the country can provide essential information for effective planning for the impending healthcare needs of the large and increasing number of individuals at risk for dementia as our population ages., ((c) 2007 S. Karger AG, Basel.)

Objective: To examine the effect of occupational characteristics on cognitive status change in members of the NAS-NRC Twins Registry of World War II veterans., Methods: Participants completed the modified Telephone Interview for Cognitive Status (TICS-m) on three occasions spanning a period of approximately 7 years. Based on factor analysis, occupational characteristics were interpreted as reflecting general intellectual demands (GI), human interaction and communication (HC), physical exertion (PE), and visual attention (VA)., Results: Based on regression analysis of TICS-m change that was dependent on twin pairing and additionally covarying for education, age at each testing event, medical conditions, and initial TICS-m score, higher GI was associated with a modest longitudinal improvement in TICS-m performance, whereas higher PE and VA were both associated with a modest decline. Subsequent analysis revealed that these significant effects were present among dizygotic twins, but not among monozygotic twins., Conclusions: Previous findings of a relationship between occupational characteristics and cognitive performance in later life may be partially explained by genetic factors; however, until these genes are identified, occupational characteristics may be useful markers.