Predictors Of Cognitive Performance Research Articles

Relationship of Change in Plasma Clozapine/N-desmethylclozapine Ratio with Cognitive Performance in Patients with Schizophrenia.

ObjectiveThe clozapine/N-desmethylclozapine (NDMC) ratio is proposed to be used as a predictor of cognitive performance in clozapine-treated patients, as its principal metabolite, NDMC, has an opposite action with clozapine on the cholinergic system. The aim of this study is to determine whether clozapine has influence on cognitive performance in accordance with changes in the clozapine/NDMC in patients with schizophrenia. MethodsThe data of fifteen patients with schizophrenia, who had initial and follow-up assessments after starting clozapine treatment, were retrospectively collected. The assessments included clinical scale, cognitive battery, and pharmacological data including plasma concentrations of clozapine and NDMC. The data were analyzed with Pearson correlation and stepwise multiple regression analyses. ResultsΔAttention/vigilance, Δsocial cognition, and Δcomposite score had a significant correlation with Δclozapine/NDMC ratio, while ΔWorking memory had correlation with Δclozapine concentration and ΔNDMC concentration, and Δsocial cognition had association with Δclozapine concentration. Multiple regression analysis showed that Δattention/vigilance had negative association with Δclozapine/NDMC ratio, Δworking memory had negative relation with Δclozapine concentration, and that Δsocial cognition had negative association with Δclozapine concentration. ConclusionThis finding implicates that lowering the clozapine/NDMC ratio could enhance cognition in patients with schizophrenia treated with clozapine.

Predictors of cognitive performance after sports concussion: preliminary report of Arg-SCARS

To investigate the predictors of cognitive performance of adult rugby players with concussion during the first 72 h. Patients with sports concussion may present cognitive deficits within the first days after neurotrauma, which in turn may lead to post-concussion syndrome and/or long-term cognitive dysfunction. Few studies investigated factors related to cognitive performance in rugby concussions players during the first 72 h. The participants were drawn from the Argentina- Sports Concussion Assessment & Research Study (Arg-SCARS). The Arg-SCARS was created to assess all rugby players in the office setting two or three days after concussion. Such multimodal assessment includes a clinical interview, symptom self-report, neurocognitive testing, and vestibular-oculomotor screening. A multiple linear regression was calculated including all participants to determine which variables predicted global cognitive performance as assessed by a global composite score. Ninety-two rugby players with concussion (aged 17-34 years) participated in the study. The mean age was 22 years-old and 71.7% of the subjects had more than 15 years of education. 20% competed in elite teams. The number of years playing rugby and of concussions was 14.72 and 1.94, respectively. The average severity score of post-concussion symptoms was 14.49. 47.3% had post-traumatic amnesia. Compared to normative data, 13.2% of subjects had reduced global memory as measured by the memory composite score. The ANOVA test showed the existence of a linear relationship between the set of predictor variables and cognitive performance (F (6) = 6,708, p = 0.002). A higher duration of post-traumatic amnesia (p = 0.037) and higher severity of post-concussion symptoms (p = 0.01) were associated with lower global cognitive composite score even after adjusting for the other variables in the model. The major determinants of poor cognitive performance in adult rugby players within the first 72 h after concussion were duration of post-traumatic amnesia and severity of post-concussion symptoms.

Association between serum NPTX2 and cognitive function in patients with vascular dementia.

ObjectiveNeuronal Pentraxin 2 (NPTX2) has recently been widely reported as a novel biomarker for Alzheimer's disease (AD), but its correlation with vascular dementia (VaD) has not been elucidated. This study aimed to explore the correlation between NPTX2 and the cognitive function of VaD patients.Methods112 VaD patients and 76 healthy controls were included in the study. Upon admission, clinical baseline data for all subjects were collected. Serum NPTX2 levels were determined using enzyme‐linked immunosorbent assay (ELISA). At the same time, the Montreal cognitive assessment (MoCA) scale was used to measure cognitive function. Multivariate regression analysis was used to determine the relationship between serum NPTX2 level and the cognitive function of VaD patients.ResultsCompared with healthy controls, VaD patients had lower serum NPTX2 levels (p < .001). The results of Spearman's correlation analysis showed that serum NPTX2 levels in VaD patients were positively correlated with MoCA scores (r = .347, p = .042). The results of multivariate regression analysis showed that after adjusting for common risk factors, serum NPTX2 levels in VaD patients were still significantly associated with MoCA scores (β = 0.346, p = .039).ConclusionsSerum NPTX2 level was independently associated with cognitive function in patients with VaD. Serum NPTX2 level may be a novel predictor for cognitive function in VaD.

Mild behavioral impairment as a predictor of cognitive functioning in older adults.

To assess the influence of mild behavioral impairment (MBI) on the cognitive performance of older adults who are cognitively healthy or have mild cognitive impairment (MCI). Secondary data analysis of a sample (n = 497) of older adults from the Florida Alzheimer's Disease Research Center who were either cognitively healthy (n = 285) or diagnosed with MCI (n = 212). Over half of the sample (n = 255) met the operationalized diagnostic criteria for MBI. Cognitive domains of executive function, attention, short-term memory, and episodic memory were assessed using a battery of neuropsychological tests. Older adults with MBI performed worse on tasks of executive function, attention, and episodic memory compared to those without MBI. A significant interaction revealed that persons with MBI and MCI performed worse on tasks of episodic memory compared to individuals with only MCI, but no significant differences were found in performance in cognitively healthy older adults with or without MBI on this cognitive domain. As expected, cognitively healthy older adults performed better than individuals with MCI on every domain of cognition. The present study found evidence that independent of cognitive status, individuals with MBI performed worse on tests of executive function, attention, and episodic memory than individuals without MBI. Additionally, those with MCI and MBI perform significantly worse on episodic memory tasks than individuals with only MCI. These results provide support for a unique cognitive phenotype associated with MBI and highlight the necessity for assessing both cognitive and behavioral symptoms.

Development of a protective mental work demands questionnaire.

Research shows that mental demands at work affect later-life cognitive functioning and dementia risk, but systematic assessment of protective mental work demands (PMWDs) is still missing. The goal of this research was to develop a questionnaire to assess PMWDs. The instrument was developed in accordance with internationally recognized scientific standards comprising conceptualization, pretesting, and validation via confirmatory factor analysis (CFA), principal component analysis (PCA), and multiple regression analyses. We included 346 participants, 72.3% female, with an average age of 56.3 years. Item pool, sociodemographic questions, and cognitive tests: Trail-Making Test A/B, Word List Recall, Verbal Fluency Test, Benton Visual Retention Test, Reading Minds in the Eyes Test. CFAs of eight existing PMWD-concepts revealed weaker fit indices than PCA of the item pool that resulted in five concepts. We computed multivariate regression analyses with all 13 PMWD-concepts as predictors of cognitive functioning. After removing PMWD-concepts that predicted less than two cognitive test scores and excluding others due to overlapping items, the final questionnaire contained four PMWD-concepts: Mental Workload (three items, Cronbach's α = .58), Verbal Demands (four, Cronbach's α = .74), Information Load (six, Cronbach's α = .83), and Extended Job Control (six, Cronbach's α = .83). The PMWD-Questionnaire intends to assess protective mental demands at the workplace. Information processing demands and job control make up the primary components emphasizing their relevance regarding cognitive health in old age. Long-term follow-up studies will need to validate construct validity with respect to dementia risk.

Gray Matter Covariance Networks as Classifiers and Predictors of Cognitive Function in Alzheimer's Disease.

The study of shared variation in gray matter morphology may define neurodegenerative diseases beyond what can be detected from the isolated assessment of regional brain volumes. We, therefore, aimed to (1) identify SCNs (structural covariance networks) that discriminate between Alzheimer’s disease (AD) patients and healthy controls (HC), (2) investigate their diagnostic accuracy in comparison and above established markers, and (3) determine if they are associated with cognitive abilities. We applied a random forest algorithm to identify discriminating networks from a set of 20 SCNs. The algorithm was trained on a main sample of 104 AD patients and 104 age-matched HC and was then validated in an independent sample of 28 AD patients and 28 controls from another center. Only two of the 20 SCNs contributed significantly to the discrimination between AD and controls. These were a temporal and a secondary somatosensory SCN. Their diagnostic accuracy was 74% in the original cohort and 80% in the independent samples. The diagnostic accuracy of SCNs was comparable with that of conventional volumetric MRI markers including whole brain volume and hippocampal volume. SCN did not significantly increase diagnostic accuracy beyond that of conventional MRI markers. We found the temporal SCN to be associated with verbal memory at baseline. No other associations with cognitive functions were seen. SCNs failed to predict the course of cognitive decline over an average of 18 months. We conclude that SCNs have diagnostic potential, but the diagnostic information gain beyond conventional MRI markers is limited.

OCT Measures as Predictors of Cognitive Function in MS Using Artificial Intelligence (621)

OCT Measures as Predictors of Cognitive Function in MS Using Artificial Intelligence (621)

Thalamus Atrophy is Not a Predictor of Cognitive Performance in Multiple Sclerosis Patients with Previous Optic Neuritis (4115)

Thalamus Atrophy is Not a Predictor of Cognitive Performance in Multiple Sclerosis Patients with Previous Optic Neuritis (4115)

The SLC6A3 gene polymorphism is related to the development of attentional functions but not to ADHD

Neuropharmacological and human clinical studies have suggested that the brain dopaminergic system is substantively involved in normal and pathological phenotypes of attention. Dopamine transporter gene (SLC6A3) was proposed as a candidate gene for Attention-Deficit/Hyperactivity Disorder (ADHD). We investigated the effect of the SLC6A3 variants on cognitive performance in ADHD and healthy children and teenagers. Participants completed cognitive tasks measuring attentional switching, selective and sustained attention, and effectiveness of alerting, orienting and executive attention. We estimated the effects of 40 bp variable number of tandem repeat (VNTR) polymorphism located in the 3′ untranslated region (3′ UTR) (9-repeat vs 10-repeat allele) of the SLC6A3 gene, ADHD diagnosis, age, and their interactions as predictors of cognitive performance. ADHD children demonstrated deficits in most of the examined attention processes, persistent within the examined age range (9–16 years). No significant effects were observed for the interaction of ADHD and the SLC6A3 polymorphism, but the results revealed a significant main effect of SLC6A3 genotype in the entire research sample. Subjects carrying 9R allele performed the switching task significantly worse in comparison to children with 10R/10R or 10R/11R genotype. SLC6A3 polymorphism moderated age-related improvements in orienting and attentional switching. Results suggest that SLC6A3 genotype influence these attentional/cognitive functions which deficits are not the key symptoms in ADHD.

Season of birth and sugary beverages are predictors of Raven\u2019s Standard Progressive Matrices Scores in adolescents

To investigate factors associated with cognitive functioning in healthy adolescents, a school-based cross-sectional study was conducted on 1370 adolescents aged 11–16 years that were randomly selected from all governorates of Kuwait. Raven’s Standard Progressive Matrices (SPM), a non-verbal test of intelligence, was used to measure cognitive functioning of the study participants. Data on predictors of cognitive functioning were collected from parents and adolescents. Weight and height of the participants were measured in a standardized manner and blood samples were tested in an accredited laboratory under strict measures of quality control. In multivariable linear regression analysis, factors that showed significant association with the SPM score were gender (p = 0.002), season of birth (p = 0.009), place of residence (p < 0.001), father’s (p < 0.001) and mother’s (p = 0.025) educational level, type of housing (p < 0.001), passive smoking at home (p = 0.031), sleeping hours during weekends (p = 0.017), students’ educational level (p < 0.001) and the frequency of consumption of sugary drinks (p < 0.001). The link between cognitive functioning and season of birth seems to be robust in various geographical locations including the Middle East. The association between sugary drinks and cognitive functioning highlights the importance of diet independently of obesity and support efforts to reduce consumption of sugary drinks among children.

Neurocognitive Frailty Index as a Predictor of Cognitive Function: An Opinion Letter

Neurocognitive Frailty Index as a Predictor of Cognitive Function: An Opinion Letter

Physical fitness and physical activity association with cognitive function and quality of life: baseline cross-sectional analysis of the PREDIMED-Plus trial

Physical activity (PA) has been hypothesized to be effective to maintaining cognitive function and delay cognitive decline in the elderly, but physical fitness (PF) could be a better predictor of cognitive function. We aimed to study the association between PA and PF with cognitive function and quality of life using cross-sectional data from 6874 participants of the PREDIMED-Plus trial (64.9 ± 4.9 years, 48.5% female). PF and PA were measured with a Chair Stand Test, the REGICOR and Rapid Assessment Physical Activity questionnaires. Cognitive function was measured with Mini-mental State Examination, Control Oral Word Association Test, Trail Making Test and Digit Span tests; whereas health-related quality of life was assessed with the SF36-HRQL test. Cognitive and quality of life scores were compared among PF quartiles and PA levels (low, moderate and high) with ANCOVA and with Chair Stand repetitions and energy expenditure from total PA with multivariable linear regression adjusted for confounding factors. PF associated with higher scores in phonemic and semantic verbal fluency tests and with lower TMT A time. However, PA was not associated with the neurocognitive parameters evaluated. Both PF and PA levels were strongly associated with a better quality of life. We concluded that PF, but not PA, is associated with a better cognitive function. This trial was retrospectively registered at the International Standard Randomized Controlled Trial (ISRCTN89898870, https://www.isrctn.com/ISRCTN89898870?q=ISRCTN89898870&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search) on 07/24/2014.

BDNF Met allele Is Associated With Lower Cognitive Function in Poststroke Rehabilitation

Background and purpose. The identification of a genetic role for cognitive outcome could influence the design of individualized treatment in poststroke rehabilitation. The aim of this study is to determine whether brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is independently associated with poststroke functional outcome. Methods. A total of 775 stroke patients with genomic data were identified from the Partners HealthCare Biobank, which contains a large number of genotypes from Biobank’s consented patients. Of 775 stroke patients who met the inclusion/exclusion criteria, 86 were enrolled. Functional outcomes were assessed using the Functional Independence Measure scores at the time of admission and discharge. Logistic and linear regression models adjusted for covariate variables, including age, sex, and medical conditions, were used to evaluate the association between BDNF Val66Met and functional outcome. Results. We detected a significant correlation between Met alleles and lower cognitive function at discharge in both ischemic and hemorrhagic stroke patients. Genotyping findings confirmed that BDNF Met allele frequency was higher in contrast to Val/Val allele frequency in lower cognitive functional recovery. Furthermore, after adjusting for covariate variables, BDNF Met alleles were found to be associated with lower cognitive outcome [P = .003; odds ratio (OR) = 5.95 (1.81-19.52)] and recovery [P = .006; OR = 3.16 (1.4-7.15)], especially with lower problem solving, expression, and social recovery in all stroke patients. Conclusions. Met allele carriers exhibited impaired poststroke cognitive function. The BDNF genotype may be a useful predictor of cognitive function in inpatient poststroke rehabilitation.

Predictors of cognitive function in pediatric brain tumor patients: Pre-surgery through 24-month follow-up

The aim of this study was to examine the feasibility of cognitive assessment from pre-surgery through 2-year follow-up in a sample of pediatric brain tumor (BT) patients. We sought to investigate cognitive function over the course of diagnosis and treatment, and as a function of presenting problems, tumor location, treatment type, and tumor severity. Using a prospective, longitudinal design, standardized IQ measures were administered to pediatric BT patients (ages 6–16) prior to surgery (n = 25), 6 months post-diagnosis (n = 24), and 24 months post-diagnosis (n = 23). Group differences emerged based on tumor severity and treatment type at multiple time points, including prior to surgical intervention; children with high grade tumors performed more poorly than children with low grade tumors, and children receiving surgery plus adjuvant therapy performed more poorly than children who received surgery only. When considered together, an analysis of covariance demonstrated that tumor grade significantly accounted for variability in cognitive functioning, while treatment type did not. Although there is overlap clinically between tumor severity and treatment received, results suggest that tumor severity is an important factor contributing to variability in cognitive functioning and should also be considered when monitoring risk for cognitive deficits in children diagnosed with BT.

Hippocampal segmentation for brains with extensive atrophy using three-dimensional convolutional neural networks.

Hippocampal volumetry is a critical biomarker of aging and dementia, and it is widely used as a predictor of cognitive performance; however, automated hippocampal segmentation methods are limited because the algorithms are (a) not publicly available, (b) subject to error with significant brain atrophy, cerebrovascular disease and lesions, and/or (c) computationally expensive or require parameter tuning. In this study, we trained a 3D convolutional neural network using 259 bilateral manually delineated segmentations collected from three studies, acquired at multiple sites on different scanners with variable protocols. Our training dataset consisted of elderly cases difficult to segment due to extensive atrophy, vascular disease, and lesions. Our algorithm, (HippMapp3r), was validated against four other publicly available state‐of‐the‐art techniques (HippoDeep, FreeSurfer, SBHV, volBrain, and FIRST). HippMapp3r outperformed the other techniques on all three metrics, generating an average Dice of 0.89 and a correlation coefficient of 0.95. It was two orders of magnitude faster than some of the tested techniques. Further validation was performed on 200 subjects from two other disease populations (frontotemporal dementia and vascular cognitive impairment), highlighting our method's low outlier rate. We finally tested the methods on real and simulated “clinical adversarial” cases to study their robustness to corrupt, low‐quality scans. The pipeline and models are available at: https://hippmapp3r.readthedocs.ioto facilitate the study of the hippocampus in large multisite studies.

Associations between functional capacity, isokinetic leg strength, sleep quality and cognitive function in multiple sclerosis patients: a cross-sectional study

ABSTRACTObjectives: Recent evidence suggests an association between functional capacity and cognitive function, at least in older adults. The aim of this cross-sectional study was to examine the association between cognitive function, functional capacity, isokinetic leg strength, health-related quality of life (HRQOL), sleep quality, body fat, handgrip strength, and fatigue among a sample of MS patients.Methods: Fifty-one relapsing-remitting MS patients (age: 38.4 ± 7.1 yrs; 30 females) were recruited and agreed to participate in this study. Cognitive function was assessed by the Paced Auditory Serial Addition Test (PASAT). Functional capacity was examined using various functional tests commonly used in MS patients. Maximal voluntary unilateral leg strength was assessed using isokinetic dynamometer. Isometric handgrip strength was assessed by a dynamometer. Total body and visceral fat levels were assessed via bioelectrical impedance analyzers. Finally, the patients’ HRQOL, sleep quality, and fatigue levels were evaluated using specific questionnaires.Results: A significant association was found between the PASAT score and the performance score in various functional capacity tests (p < 0.050). On the other hand, a weak but statistically significant association was found between the PASAT score and isokinetic strength of knee extensors (r = 0.319, p = 0.022) and knee flexors (r = 0.354 p = 0.011). Poor sleep quality was associated with lower performance in all the functional capacity tests examined (p < 0.05) whilst was negatively associated with the PASAT score (r = −0.334, p = 0.017). The multivariate regression analysis revealed that the performance on the TUG test was a significant predictor of cognitive function.Conclusion: Based on the results of this study, functional capacity was found to be associated with both impaired cognitive performance and low HRQOL in MS patients. In addition, an association between sleep quality and cognitive performance was revealed, confirming existing literature. Functional capacity as assessed by the TUG test emerged as the best predictor of cognitive function.

A Prospective Study on the Association Between Grip Strength and Cognitive Function Among Middle-Aged and Elderly Chinese Participants.

ObjectiveTo study the efficacy of grip strength (GS) as a predictor of cognitive function in a large, nationwide sample of Chinese participants aged 45 years and above.MethodsWe used data from three waves (W1, W2, and W3) fielded by the China Health and Retirement Longitudinal Study (CHARLS). Cognitive function was tested biennially and calculated using two categories: episodic memory and mental intactness. Demographics, health behaviors, and medical conditions were considered potential confounders. Using multivariate linear regression models (MLRMs), we examined the association between baseline GS (measure in W1) and cognitive function in W3. Using a generalized estimating equation (GEE), we examined baseline GS as a predictor of cognitive function change.ResultsTotal 9,333 individuals (53.2% women), with a mean baseline episodic memory score of 6.5, mean baseline mental intactness score of 7.2, and aged over 45 years (mean age = 58.6), were selected. The mean follow-up time was 4.0 years (range: 3.3–5.0 years). Using MLRMs and comparing the lowest GS score with the highest baseline GS score, we observed a significant correlation with a higher global cognitive function in both women (β = 1.061, p < 0.001) and men (β = 1.233, p < 0.001). After adjusting baseline global cognition, the highest GS level was still statistically significant in both women (β = 0.543, p < 0.05) and men (β = 0.742, p < 0.001). GEE suggested that the participants in the highest GS quartile had better cognitive performance over time in both women (β = 0.116, p = 0.030) and men (β = 0.143, p = 0.008) than those in the lowest quartile.ConclusionHigher baseline level of GS was significantly related to better cognitive function and slowed the rate of its decline. Thus, it is an independent predictor of better cognitive status in middle-aged and elderly Chinese.

Predictors of cognitive functioning after carotid revascularization

PurposeHigh-grade carotid stenosis can affect cognition, but the relationship between stenosis correction and cognitive outcome is not fully understood, yet. The aim of this study was to evaluate the predictors of post-operative neurocognitive functioning in patients with symptomatic severe internal carotid artery (ICA) stenosis undergoing carotid endarterectomy (CEA). Materials and methodsPatients with history of transient ischemic attack within the past 6 months and ipsilateral high-grade stenosis of ICA undergoing CEA were prospectively enrolled. Cerebral hemodynamics was assessed by means of the cerebral vasomotor reactivity (CVR) to hypercapnia measured through transcranial Doppler ultrasonography. Coloured Progressive Matrices plus Complex Figure Copy Test, and phonemic plus categorical (ca) Verbal Fluency tests were performed to assess right and left hemisphere cognitive functions, respectively. Cerebral hemodynamics and cognitive functions were assessed before and 6 months after CEA. ResultsOne hundred and eighty-one patients were included. The mean age was 73.2 (6.9) years and 121 (66.9%) were males. At 6 months from CEA, the scores obtained in the cognitive tests exploring the re-vascularized hemisphere's functions and ipsilateral cerebral hemodynamics were improved. At multivariate linear regression analysis, the 6-month change in cognitive performance was inversely associated with age [ß = −0.17, 95% confidence interval (CI) −0.22 to −0.12; p < .001] and CVR value obtained before CEA on the side of ICA stenosis (ß = −6.25, 95% CI −7.40 to −5.10; p < .001). ConclusionsIn patients with symptomatic high-grade ICA stenosis, age and cerebral hemodynamic status before CEA predicted the neurocognitive performance changes after surgical stenosis correction.

Reproductive History and Cognitive Aging: The Bogalusa Heart Study

BackgroundAlthough it has become increasingly clear that pregnancy-related health predicts later-life cardiometabolic health, the relationship between reproductive history and cognitive health is less frequently studied. Although some research has identified associations between parity or hypertensive disorders of pregnancy and cognitive changes, the evidence is mixed. ObjectiveTo examine the association between reproductive history and midlife cognition in a community-based population. Study designSeven hundred and thirty midlife women in the Bogalusa Heart Study completed a brief cognitive battery (memory, attention, executive function, and processing speed) and were interviewed about their reproductive history. Reproductive history (parity, age at first pregnancy, and breastfeeding) and pregnancy complications (low birthweight, preterm birth, hypertensive disorders, and miscarriage) were examined as predictors of cognitive function, with adjustment for potential confounders. ResultsNulliparous women had an overall lower cognitive score (adjusted beta −1.50, standard error [SE]: 0.41). Adolescent birth was associated with a somewhat better performance on the Trail Making Test (beta −0.31, SE: 0.15 for birth <16 years), while high parity was not strongly associated with any of the cognitive measures. History of pregnancy complications was not strongly associated with cognitive function, whereas history of miscarriage was associated with better cognitive function, as was a history of breastfeeding (beta overall score 0.90, SE: 0.29), particularly noticeable for semantic memory and in those with more total breastfeeding time (beta for overall score among those with >24 weeks lifetime breastfeeding, beta 1.21, SE: 0.44). ConclusionNulliparity and breastfeeding are associated with midlife cognition in women. Future studies should examine possible mechanisms by which these associations are created.

Homocysteine, rather than age of onset, is a better predictor for cognitive function in older adults with bipolar disorder.

The association between older-age bipolar disorder and cognitive impairments may be mediated by vascular burden. The aim of the study was to examine the difference of cognitive function between older people with late-onset bipolar disorder (LOBD) and early-onset bipolar disorder (EOBD) by considering rigorous vascular risk burden evaluation, comprehensive cognitive tests, and relevant biochemistry data. We recruited 95 outpatients aged over 55 with a DSM-IV-TR diagnosis of bipolar I disorder. Fifty had LOBD, defined by age of onset after 40. Cognitive function was evaluated through a battery of tests assessing verbal memory, attention/speed, visuospatial function, verbal fluency, and cognitive flexibility. Vascular risk assessments included individual disorders, 10-year Framingham cardiovascular risk scores, and serum levels of homocysteine, vitamin B12, folate, and triiodothyronine. No differences were observed between LOBD and EOBD on any cognitive test after adjusting for potential confounders. In addition to age and educational years, multiple linear regression analyses indicated significantly negative associations between serum homocysteine levels and cognitive performances in attention, psychomotor speed, verbal memory, and executive function. Among older people with bipolar disorder, LOBD is not associated with more cognitive dysfunction in this study. However, higher serum homocysteine levels were significantly associated with worse cognitive performance in this particular group. Clinicians therefore have to pay attention to the cognitive function in older bipolar patients with higher levels of homocysteine.