@article {641, title = {Normative data on the Boston Naming Test and two equivalent 30-item short forms.}, journal = {Clin Neuropsychol}, volume = {14}, year = {2000}, month = {2000 Nov}, pages = {526-34}, abstract = {

Because of the significance of the Boston Naming Test (BNT) in the differential diagnosis of the dementias, especially Alzheimer{\textquoteright}s disease, adequate norms from community-dwelling elderly individuals are essential. The present study describes the development of two new empirically derived equivalent short forms (30 items each) of the test. Normative data for the total BNT and the two equivalent 30-item halves based on item difficulty are presented using the performance of 314 community-dwelling individuals aged 65 and over. Age and education norms are presented using an overlapping midpoint interval strategy.

}, keywords = {Aged, Aged, 80 and over, Alzheimer Disease, Female, Humans, Male, Neuropsychological Tests, Population Surveillance, Reference Values}, issn = {1385-4046}, doi = {10.1076/clin.14.4.526.7204}, author = {Saxton, J and Ratcliff, G and Munro, C A and Coffey, E C and Becker, J T and Fried, L and Kuller, L} } @article {837, title = {Classification of vascular dementia in the Cardiovascular Health Study Cognition Study.}, journal = {Neurology}, volume = {64}, year = {2005}, month = {2005 May 10}, pages = {1539-47}, abstract = {

OBJECTIVE: To describe the diagnostic classification of subjects with incident vascular dementia (VaD) participating in the Cardiovascular Health Study (CHS) Cognition Study.

METHODS: The CHS classified 480 incident cases between 1994 and 1999 among 3,608 CHS participants who had brain MRI in 1992 through 1994 and in 1997 through 1998. The patients were diagnosed before and after reviewing the brain MRI.

RESULTS: The pre-MRI classification showed that 52 participants had VaD and 76 had both Alzheimer disease (AD) and VaD. The post-MRI classification showed that the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) criteria classified 61 subjects as having VaD, the National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l{\textquoteright}Enseignement en Neurosciences (NINDS-AIREN) criteria classified 43 subjects as having probable VaD and 10 as possible VaD, and the State of California Alzheimer{\textquoteright}s Disease Diagnostic and Treatment Center (ADDTC) criteria classified 117 as having probable VaD and 96 as possible. The combination of the ADDTC and National Institute of Neurological and Communication Disorders and Stroke-Alzheimer{\textquoteright}s Disease and Related Disorders Association criteria was used to examine the spectrum of vascular disease in dementia. The dementia was attributable to only vascular factors in 56 cases (probable VaD); VaD coexisted with AD in 61 cases, although the VaD component was the leading cause of dementia (probable VaD with AD); AD was the leading cause of dementia in 61 cases (possible VaD and probable AD); and in 29 cases, it was not clear that either AD or VaD was the primary diagnosis (possible AD and possible VaD).

CONCLUSIONS: None of the clinical criteria for VaD identified the same group of subjects. The diagnosis of vascular dementia is difficult in epidemiologic studies because poststroke dementia can be due to Alzheimer disease (AD) and evidence of vascular disease can be found in the MRI of dementia cases without clinical strokes. Whether the clinical progression is related to AD pathology or vascular disease is difficult to establish.

}, keywords = {Aged, Aged, 80 and over, Alzheimer Disease, Brain, Cerebral Arteries, Cohort Studies, Dementia, Vascular, Diagnosis, Differential, Disease Progression, Female, Humans, Magnetic Resonance Imaging, Male, Predictive Value of Tests, Stroke, United States}, issn = {1526-632X}, doi = {10.1212/01.WNL.0000159860.19413.C4}, author = {Lopez, O L and Kuller, L H and Becker, J T and Jagust, W J and DeKosky, S T and Fitzpatrick, A and Breitner, J and Lyketsos, C and Kawas, C and Carlson, M} } @article {838, title = {Determinants of vascular dementia in the Cardiovascular Health Cognition Study.}, journal = {Neurology}, volume = {64}, year = {2005}, month = {2005 May 10}, pages = {1548-52}, abstract = {

OBJECTIVE: The authors evaluated 3,375 participants without dementia at the time of MRI in 1991 to 1994 over 5.7 years for incident dementia and type of dementia.

METHODS: Incidence of and risk factors for vascular dementia (VaD) were measured using both pre-MRI and modified State of California Alzheimer{\textquoteright}s Disease Diagnostic and Treatment Centers (ADDTC) post-MRI review and further classified Alzheimer disease (AD) by the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer{\textquoteright}s Disease and Related Disorders Association (NINCDS-ADRDA) criteria.

RESULTS: Approximately 44\% (213) of 480 incident dementia cases were classified as possible or probable VaD by ADDTC. The incidence of VaD increased with age and was greater in blacks than whites. Risk factors for VaD included age, Modified Mini-Mental State Examination, high white matter grade, number of MRI infarcts, ventricular size, and history of stroke.

CONCLUSIONS: Vascular disease in the brain is prevalent among incident dementia cases. There is a substantial overlap between cases classified as Alzheimer disease by Neurological and Communicative Disorders and Stroke and the Alzheimer{\textquoteright}s Disease and Related Disorders Association and vascular dementia (VaD) by modified State of California Alzheimer{\textquoteright}s Disease Diagnostic and Treatment Centers criteria. The substantial contribution of vascular disease would be missed without inclusion of MRI. Treatment of risk factors for VaD could have an important impact on incidence of dementia.

}, keywords = {Age Factors, Aged, Aged, 80 and over, Alzheimer Disease, Atrophy, Brain, Cardiovascular Diseases, Cerebral Arteries, Cerebral Infarction, Cohort Studies, Comorbidity, Continental Population Groups, Dementia, Vascular, Female, Humans, Lateral Ventricles, Magnetic Resonance Imaging, Male, Nerve Fibers, Myelinated, Neuropsychological Tests, Risk Factors, Sex Factors}, issn = {1526-632X}, doi = {10.1212/01.WNL.0000160115.55756.DE}, author = {Kuller, L H and Lopez, O L and Jagust, W J and Becker, J T and DeKosky, S T and Lyketsos, C and Kawas, C and Breitner, J C S and Fitzpatrick, A and Dulberg, C} } @article {851, title = {Neuropsychological characteristics of mild cognitive impairment subgroups.}, journal = {J Neurol Neurosurg Psychiatry}, volume = {77}, year = {2006}, month = {2006 Feb}, pages = {159-65}, abstract = {

OBJECTIVE: To describe the neuropsychological characteristics of mild cognitive impairment (MCI) subgroups identified in the Cardiovascular Health Study (CHS) cognition study.

METHODS: MCI was classified as MCI-amnestic type (MCI-AT): patients with documented memory deficits but otherwise normal cognitive function; and MCI-multiple cognitive deficits type (MCI-MCDT): impairment of at least one cognitive domain (not including memory), or one abnormal test in at least two other domains, but who had not crossed the dementia threshold. The MCI subjects did not have systemic, neurological, or psychiatric disorders likely to affect cognition.

RESULTS: MCI-AT (n = 10) had worse verbal and non-verbal memory performance than MCI-MCDT (n = 28) or normal controls (n = 374). By contrast, MCI-MCDT had worse language, psychomotor speed, fine motor control, and visuoconstructional function than MCI-AT or normal controls. MCI-MCDT subjects had memory deficits, though they were less pronounced than in MCI-AT. Of the MCI-MCDT cases, 22 (78.5\%) had memory deficits, and 6 (21.5\%) did not. MCI-MCDT with memory disorders had more language deficits than MCI-MCDT without memory disorders. By contrast, MCI-MCDT without memory deficits had more fine motor control deficits than MCI-MCDT with memory deficits.

CONCLUSIONS: The most frequent form of MCI was the MCI-MCDT with memory deficits. However, the identification of memory impaired MCI groups did not reflect the true prevalence of MCI in a population, as 16\% of all MCI cases and 21.5\% of the MCI-MCDT cases did not have memory impairment. Study of idiopathic amnestic and non-amnestic forms of MCI is essential for an understanding of the aetiology of MCI.

}, keywords = {Aged, Aged, 80 and over, Alzheimer Disease, Amnesia, Cognition Disorders, Female, Humans, Male, Neuropsychological Tests, Psychometrics, Reference Values}, issn = {0022-3050}, doi = {10.1136/jnnp.2004.045567}, author = {Lopez, O L and Becker, J T and Jagust, W J and Fitzpatrick, A and Carlson, M C and DeKosky, S T and Breitner, J and Lyketsos, C G and Jones, B and Kawas, C and Kuller, L H} } @article {909, title = {Acceleration of cerebral ventricular expansion in the Cardiovascular Health Study.}, journal = {Neurobiol Aging}, volume = {28}, year = {2007}, month = {2007 Sep}, pages = {1316-21}, abstract = {

Interactions between prevalent late-life medical conditions and expansion of the cerebral ventricles are not well understood. Thirty elderly subjects received three magnetic resonance (MR) scans each, in 1997-1999, 2002-2004, and 2003-2005. A linear expansion model of MR-measured lateral ventricle volume was estimated for each subject by fitting a line to a plot of their 1997-1999 and 2002-2004 volumes as a function of time. Acceleration in ventricular expansion was defined as the deviation between the 2003-2005 volumes measured from MR and the 2003-2005 volumes predicted by the linear expansion model. Ventricular acceleration was analyzed in a multivariate model with age, race, history of heart disease, diabetes, and hypertension as fixed effects. Ventricular acceleration was significantly higher in non-whites, diabetics, and those without heart disease (p<0.05). Ventricular acceleration was higher in subjects with a history of hypertension, but the difference was not statistically significant (p=0.08). Acceleration of ventricular expansion in the elderly may be related to demographic and cardiovascular factors.

}, keywords = {Aged, Analysis of Variance, Cardiovascular Diseases, Cerebral Ventricles, Female, Humans, Longitudinal Studies, Magnetic Resonance Imaging, Male, Reference Values, Retrospective Studies, Sex Factors, Time Factors}, issn = {1558-1497}, doi = {10.1016/j.neurobiolaging.2006.06.016}, author = {Carmichael, Owen T and Kuller, L H and Lopez, O L and Thompson, P M and Dutton, R A and Lu, A and Lee, S E and Lee, J Y and Aizenstein, H J and Meltzer, C C and Liu, Y and Toga, A W and Becker, J T} } @article {1025, title = {Plasma amyloid levels and the risk of AD in normal subjects in the Cardiovascular Health Study.}, journal = {Neurology}, volume = {70}, year = {2008}, month = {2008 May 06}, pages = {1664-71}, abstract = {

OBJECTIVES: To examine the association between incident Alzheimer disease (AD), and plasma A beta 1-40 and A beta 1-42 levels in normal and mild cognitive impairment (MCI) subjects in a subgroup of participants of the Cardiovascular Health Study Cognition Study.

METHODS: We determined the plasma A beta 1-40 and A beta 1-42 levels of 274 nondemented subjects (232 normals and 42 with MCI) in 1998-1999 and repeated the measurements in 2002-2003. The mean age of the subjects at baseline was 79.3 +/- 3.6 years. We examined the association between A beta levels and incident AD over the ensuing 4.5 years, controlling for age, cystatin C level (marker of glomerular function), apolipoprotein E-4 allele, Modified-Mini-Mental State Examination scores, and MRI-identified infarcts.

RESULTS: In an unadjusted prospective model in normal subjects, both A beta 1-40 and A beta 1-42 levels in 1998-1999 were associated with incident AD (n = 55) in 2002-2003 (longitudinal analysis). In the fully adjusted multivariate model, neither A beta 1-42 nor A beta 1-40 nor their ratio was associated with incident AD. However, adjustment had a very small effect on point estimates for A beta 1-42, from an odds ratio (OR) of 1.61 (p = 0.007) in the unadjusted model to an OR of 1.46 (p = 0.08) in the fully adjusted model. In 2002-2003 (cross-sectional analysis), only the unadjusted models showed that both peptides were associated with AD.

CONCLUSIONS: Plasma A beta levels are affected by age and by systemic and CNS vascular risk factors. After controlling for these conditions, A beta-40 and A beta 1-42 are weak predictors of conversion to Alzheimer disease (AD) in normal subjects and are only weakly associated with AD in cross-sectional analysis. Consequently, plasma levels of A beta do not seem to be useful biomarkers for AD.

}, keywords = {Age Factors, Aged, Aged, 80 and over, Alzheimer Disease, Amyloid beta-Peptides, Apolipoprotein E4, Biomarkers, Brain, Cerebrovascular Disorders, Comorbidity, Cross-Sectional Studies, Cystatin C, Cystatins, Female, Humans, Incidence, Longitudinal Studies, Magnetic Resonance Imaging, Male, Models, Statistical, Neuropsychological Tests, Peptide Fragments, Predictive Value of Tests, Prospective Studies, Reference Values, Risk Factors}, issn = {1526-632X}, doi = {10.1212/01.wnl.0000306696.82017.66}, author = {Lopez, O L and Kuller, L H and Mehta, P D and Becker, J T and Gach, H M and Sweet, R A and Chang, Y F and Tracy, R and DeKosky, S T} } @article {1140, title = {Age, Alzheimer disease, and brain structure.}, journal = {Neurology}, volume = {73}, year = {2009}, month = {2009 Dec 01}, pages = {1899-905}, abstract = {

BACKGROUND: Lack of clear understanding remains on the overlapping atrophy patterns of aging and early Alzheimer disease (AD) pathology in gray matter (GM) of the brain in vivo.

OBJECTIVE: To evaluate the independent and overlapping patterns of GM atrophy in normal aging and AD.

METHODS: A total of 169 cognitively normal subjects and 33 persons with probable AD enrolled in the longitudinal Cardiovascular Health Study-Cognition Study underwent 3-dimensional volumetric MRI scans. Controls remained cognitively normal for at least 5 years after their MRI scans and the probable AD subjects were relatively early in their clinical course with an average modified Mini-Mental State Examination score of 76/100. The scans were analyzed using voxel-based morphometry adjusting for total intracranial volume, gender, education, and race.

RESULTS: With older age, GM volume was lower in the sensorimotor and heteromodal association areas in frontal, temporal, occipital, and parietal lobes, as well as in the cerebellum (false discovery rate p = 0.05). Additional atrophy was observed in the posterior hippocampus, thalamus, and middle cingulate gyrus. By contrast, atrophy was seen in subjects with AD in the anterior hippocampal/parahippocampal regions and the precuneus. Normal aging and AD overlapped in the hippocampal body and the entorhinal cortex.

CONCLUSION: Brain atrophy with aging was observed in supratentorial and infratentorial areas, as well in primary motor, sensory, and heteromodal association regions. Age and Alzheimer disease exert independent gray matter atrophy patterns but these effects overlapped substantially in the hippocampus and entorhinal cortex.

}, keywords = {Aged, Aged, 80 and over, Aging, Alzheimer Disease, Brain, Brain Mapping, Cognition Disorders, Female, Humans, Image Processing, Computer-Assisted, Linear Models, Magnetic Resonance Imaging, Male, Neuropsychological Tests, Retrospective Studies}, issn = {1526-632X}, doi = {10.1212/WNL.0b013e3181c3f293}, author = {Raji, C A and Lopez, O L and Kuller, L H and Carmichael, O T and Becker, J T} } @article {1239, title = {Physical activity predicts gray matter volume in late adulthood: the Cardiovascular Health Study.}, journal = {Neurology}, volume = {75}, year = {2010}, month = {2010 Oct 19}, pages = {1415-22}, abstract = {

OBJECTIVES: Physical activity (PA) has been hypothesized to spare gray matter volume in late adulthood, but longitudinal data testing an association has been lacking. Here we tested whether PA would be associated with greater gray matter volume after a 9-year follow-up, a threshold could be identified for the amount of walking necessary to spare gray matter volume, and greater gray matter volume associated with PA would be associated with a reduced risk for cognitive impairment 13 years after the PA evaluation.

METHODS: In 299 adults (mean age 78 years) from the Cardiovascular Health Cognition Study, we examined the association between gray matter volume, PA, and cognitive impairment. Physical activity was quantified as the number of blocks walked over 1 week. High-resolution brain scans were acquired 9 years after the PA assessment on cognitively normal adults. White matter hyperintensities, ventricular grade, and other health variables at baseline were used as covariates. Clinical adjudication for cognitive impairment occurred 13 years after baseline.

RESULTS: Walking amounts ranged from 0 to 300 blocks (mean 56.3; SD 69.7). Greater PA predicted greater volumes of frontal, occipital, entorhinal, and hippocampal regions 9 years later. Walking 72 blocks was necessary to detect increased gray matter volume but walking more than 72 blocks did not spare additional volume. Greater gray matter volume with PA reduced the risk for cognitive impairment 2-fold.

CONCLUSION: Greater amounts of walking are associated with greater gray matter volume, which is in turn associated with a reduced risk of cognitive impairment.

}, keywords = {Aged, Aged, 80 and over, Brain, Brain Mapping, Cardiovascular Diseases, Cognition Disorders, Female, Humans, Longitudinal Studies, Magnetic Resonance Imaging, Male, Mental Status Schedule, Motor Activity, Neuropsychological Tests, Odds Ratio, Predictive Value of Tests, Surveys and Questionnaires}, issn = {1526-632X}, doi = {10.1212/WNL.0b013e3181f88359}, author = {Erickson, K I and Raji, C A and Lopez, O L and Becker, J T and Rosano, C and Newman, A B and Gach, H M and Thompson, P M and Ho, A J and Kuller, L H} } @article {6365, title = {Physical activity, inflammation, and volume of the aging brain.}, journal = {Neuroscience}, volume = {273}, year = {2014}, month = {2014 Jul 25}, pages = {199-209}, abstract = {

Physical activity influences inflammation, and both affect brain structure and Alzheimer{\textquoteright}s disease (AD) risk. We hypothesized that older adults with greater reported physical activity intensity and lower serum levels of the inflammatory marker tumor necrosis factor α (TNFα) would have larger regional brain volumes on subsequent magnetic resonance imaging (MRI) scans. In 43 cognitively intact older adults (79.3{\textpm}4.8 years) and 39 patients with AD (81.9{\textpm}5.1 years at the time of MRI) participating in the Cardiovascular Health Study, we examined year-1 reported physical activity intensity, year-5 blood serum TNFα measures, and year-9 volumetric brain MRI scans. We examined how prior physical activity intensity and TNFα related to subsequent total and regional brain volumes. Physical activity intensity was measured using the modified Minnesota Leisure Time Physical Activities questionnaire at year 1 of the study, when all subjects included here were cognitively intact. Stability of measures was established for exercise intensity over 9 years and TNFα over 3 years in a subset of subjects who had these measurements at multiple time points. When considered together, more intense physical activity intensity and lower serum TNFα were both associated with greater total brain volume on follow-up MRI scans. TNFα, but not physical activity, was associated with regional volumes of the inferior parietal lobule, a region previously associated with inflammation in AD patients. Physical activity and TNFα may independently influence brain structure in older adults.

}, keywords = {Aged, Aged, 80 and over, Aging, Alzheimer Disease, Apolipoproteins E, Brain, Female, Humans, Inflammation, Longitudinal Studies, Magnetic Resonance Imaging, Male, Motor Activity, Neuroimmunomodulation, Neuropsychological Tests, Organ Size, Parietal Lobe, Surveys and Questionnaires, Tumor Necrosis Factor-alpha}, issn = {1873-7544}, doi = {10.1016/j.neuroscience.2014.05.005}, author = {Braskie, M N and Boyle, C P and Rajagopalan, P and Gutman, B A and Toga, A W and Raji, C A and Tracy, R P and Kuller, L H and Becker, J T and Lopez, O L and Thompson, P M} } @article {6816, title = {Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53949).}, journal = {Mol Psychiatry}, volume = {20}, year = {2015}, month = {2015 Feb}, pages = {183-92}, abstract = {

General cognitive function is substantially heritable across the human life course from adolescence to old age. We investigated the genetic contribution to variation in this important, health- and well-being-related trait in middle-aged and older adults. We conducted a meta-analysis of genome-wide association studies of 31 cohorts (N=53,949) in which the participants had undertaken multiple, diverse cognitive tests. A general cognitive function phenotype was tested for, and created in each cohort by principal component analysis. We report 13 genome-wide significant single-nucleotide polymorphism (SNP) associations in three genomic regions, 6q16.1, 14q12 and 19q13.32 (best SNP and closest gene, respectively: rs10457441, P=3.93 {\texttimes} 10(-9), MIR2113; rs17522122, P=2.55 {\texttimes} 10(-8), AKAP6; rs10119, P=5.67 {\texttimes} 10(-9), APOE/TOMM40). We report one gene-based significant association with the HMGN1 gene located on chromosome 21 (P=1 {\texttimes} 10(-6)). These genes have previously been associated with neuropsychiatric phenotypes. Meta-analysis results are consistent with a polygenic model of inheritance. To estimate SNP-based heritability, the genome-wide complex trait analysis procedure was applied to two large cohorts, the Atherosclerosis Risk in Communities Study (N=6617) and the Health and Retirement Study (N=5976). The proportion of phenotypic variation accounted for by all genotyped common SNPs was 29\% (s.e.=5\%) and 28\% (s.e.=7\%), respectively. Using polygenic prediction analysis, ~1.2\% of the variance in general cognitive function was predicted in the Generation Scotland cohort (N=5487; P=1.5 {\texttimes} 10(-17)). In hypothesis-driven tests, there was significant association between general cognitive function and four genes previously associated with Alzheimer{\textquoteright}s disease: TOMM40, APOE, ABCG1 and MEF2C.

}, keywords = {Aged, Aged, 80 and over, Atherosclerosis, Cognition, Cognition Disorders, Cohort Studies, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, HMGN1 Protein, Humans, Male, Middle Aged, Neuropsychological Tests, Phenotype, Polymorphism, Single Nucleotide, Scotland}, issn = {1476-5578}, doi = {10.1038/mp.2014.188}, author = {Davies, G and Armstrong, N and Bis, J C and Bressler, J and Chouraki, V and Giddaluru, S and Hofer, E and Ibrahim-Verbaas, C A and Kirin, M and Lahti, J and van der Lee, S J and Le Hellard, S and Liu, T and Marioni, R E and Oldmeadow, C and Postmus, I and Smith, A V and Smith, J A and Thalamuthu, A and Thomson, R and Vitart, V and Wang, J and Yu, L and Zgaga, L and Zhao, W and Boxall, R and Harris, S E and Hill, W D and Liewald, D C and Luciano, M and Adams, H and Ames, D and Amin, N and Amouyel, P and Assareh, A A and Au, R and Becker, J T and Beiser, A and Berr, C and Bertram, L and Boerwinkle, E and Buckley, B M and Campbell, H and Corley, J and De Jager, P L and Dufouil, C and Eriksson, J G and Espeseth, T and Faul, J D and Ford, I and Gottesman, R F and Griswold, M E and Gudnason, V and Harris, T B and Heiss, G and Hofman, A and Holliday, E G and Huffman, J and Kardia, S L R and Kochan, N and Knopman, D S and Kwok, J B and Lambert, J-C and Lee, T and Li, G and Li, S-C and Loitfelder, M and Lopez, O L and Lundervold, A J and Lundqvist, A and Mather, K A and Mirza, S S and Nyberg, L and Oostra, B A and Palotie, A and Papenberg, G and Pattie, A and Petrovic, K and Polasek, O and Psaty, B M and Redmond, P and Reppermund, S and Rotter, J I and Schmidt, H and Schuur, M and Schofield, P W and Scott, R J and Steen, V M and Stott, D J and van Swieten, J C and Taylor, K D and Trollor, J and Trompet, S and Uitterlinden, A G and Weinstein, G and Widen, E and Windham, B G and Jukema, J W and Wright, A F and Wright, M J and Yang, Q and Amieva, H and Attia, J R and Bennett, D A and Brodaty, H and de Craen, A J M and Hayward, C and Ikram, M A and Lindenberger, U and Nilsson, L-G and Porteous, D J and R{\"a}ikk{\"o}nen, K and Reinvang, I and Rudan, I and Sachdev, P S and Schmidt, R and Schofield, P R and Srikanth, V and Starr, J M and Turner, S T and Weir, D R and Wilson, J F and van Duijn, C and Launer, L and Fitzpatrick, A L and Seshadri, S and Mosley, T H and Deary, I J} } @article {6799, title = {GWAS for executive function and processing speed suggests involvement of the CADM2 gene.}, journal = {Mol Psychiatry}, volume = {21}, year = {2016}, month = {2016 Feb}, pages = {189-97}, abstract = {

To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium. Neuropsychological testing was available for 5429-32,070 subjects of European ancestry aged 45 years or older, free of dementia and clinical stroke at the time of cognitive testing from 20 cohorts in the discovery phase. We analyzed performance on the Trail Making Test parts A and B, the Letter Digit Substitution Test (LDST), the Digit Symbol Substitution Task (DSST), semantic and phonemic fluency tests, and the Stroop Color and Word Test. Replication was sought in 1311-21860 subjects from 20 independent cohorts. A significant association was observed in the discovery cohorts for the single-nucleotide polymorphism (SNP) rs17518584 (discovery P-value=3.12 {\texttimes} 10(-8)) and in the joint discovery and replication meta-analysis (P-value=3.28 {\texttimes} 10(-9) after adjustment for age, gender and education) in an intron of the gene cell adhesion molecule 2 (CADM2) for performance on the LDST/DSST. Rs17518584 is located about 170 kb upstream of the transcription start site of the major transcript for the CADM2 gene, but is within an intron of a variant transcript that includes an alternative first exon. The variant is associated with expression of CADM2 in the cingulate cortex (P-value=4 {\texttimes} 10(-4)). The protein encoded by CADM2 is involved in glutamate signaling (P-value=7.22 {\texttimes} 10(-15)), gamma-aminobutyric acid (GABA) transport (P-value=1.36 {\texttimes} 10(-11)) and neuron cell-cell adhesion (P-value=1.48 {\texttimes} 10(-13)). Our findings suggest that genetic variation in the CADM2 gene is associated with individual differences in information processing speed.

}, issn = {1476-5578}, doi = {10.1038/mp.2015.37}, author = {Ibrahim-Verbaas, C A and Bressler, J and Debette, S and Schuur, M and Smith, A V and Bis, J C and Davies, G and Trompet, S and Smith, J A and Wolf, C and Chibnik, L B and Liu, Y and Vitart, V and Kirin, M and Petrovic, K and Polasek, O and Zgaga, L and Fawns-Ritchie, C and Hoffmann, P and Karjalainen, J and Lahti, J and Llewellyn, D J and Schmidt, C O and Mather, K A and Chouraki, V and Sun, Q and Resnick, S M and Rose, L M and Oldmeadow, C and Stewart, M and Smith, B H and Gudnason, V and Yang, Q and Mirza, S S and Jukema, J W and deJager, P L and Harris, T B and Liewald, D C and Amin, N and Coker, L H and Stegle, O and Lopez, O L and Schmidt, R and Teumer, A and Ford, I and Karbalai, N and Becker, J T and Jonsdottir, M K and Au, R and Fehrmann, R S N and Herms, S and Nalls, M and Zhao, W and Turner, S T and Yaffe, K and Lohman, K and van Swieten, J C and Kardia, S L R and Knopman, D S and Meeks, W M and Heiss, G and Holliday, E G and Schofield, P W and Tanaka, T and Stott, D J and Wang, J and Ridker, P and Gow, A J and Pattie, A and Starr, J M and Hocking, L J and Armstrong, N J and McLachlan, S and Shulman, J M and Pilling, L C and Eiriksdottir, G and Scott, R J and Kochan, N A and Palotie, A and Hsieh, Y-C and Eriksson, J G and Penman, A and Gottesman, R F and Oostra, B A and Yu, L and DeStefano, A L and Beiser, A and Garcia, M and Rotter, J I and N{\"o}then, M M and Hofman, A and Slagboom, P E and Westendorp, R G J and Buckley, B M and Wolf, P A and Uitterlinden, A G and Psaty, B M and Grabe, H J and Bandinelli, S and Chasman, D I and Grodstein, F and R{\"a}ikk{\"o}nen, K and Lambert, J-C and Porteous, D J and Price, J F and Sachdev, P S and Ferrucci, L and Attia, J R and Rudan, I and Hayward, C and Wright, A F and Wilson, J F and Cichon, S and Franke, L and Schmidt, H and Ding, J and de Craen, A J M and Fornage, M and Bennett, D A and Deary, I J and Ikram, M A and Launer, L J and Fitzpatrick, A L and Seshadri, S and van Duijn, C M and Mosley, T H} }