Socioeconomic status moderates the association between carotid intima-media thickness and cognition in midlife: evidence from the Whitehall II study

Associations of carotid atherosclerosis with cognitive function and brain health: Findings from a UK tri-ethnic cohort study (Southall and Brent Revisited)

Background

Cognitive function has an important role in determining the quality of life of older adults. Cardiovascular disease (CVD) is common in older people and may compromise cognitive performance; however, the extent to which this is related to carotid atherosclerosis is unclear.

Aim

We investigated associations between carotid atherosclerosis and cognitive function and neuroimaging markers of brain health in a UK multi-ethnic community-based sample including older people of European, South Asian, and African-Caribbean ethnicity.

Methods

Carotid plaques and intima-media thickness (cIMT) were assessed using ultrasound in 985 people (mean age 73.2y, 56 % male). Associations of carotid atherosclerosis with cognitive function (memory, executive function, language and CSI-D, a global measure of cognitive state) and neuroimaging measures (total brain volume, hippocampal volume, white matter (WM) lesion volume and coalescence score) were analysed using regression analyses, with and without adjustment for potential confounders using two models: 1) adjustment for age, sex, and ethnicity; 2) model 1 plus education, physical activity category, body mass index, hypertension, diabetes, total and high density lipoprotein cholesterol, atrial fibrillation, smoking, previous CVD, alcohol consumption, and presence of chronic kidney disease.

Results

People with carotid plaque or higher cIMT had lower CSI-D score, poorer memory poorer executive function and higher WM lesion volume and coalescence. Language was poorer in people with plaque but was not correlated with cIMT. Associations with plaque were preserved after full adjustment (model 2) but relationships for cIMT were attenuated. Associations with other plaque characteristics were generally unconvincing after adjustment.

Conclusions

This multi-ethnic cohort study provides evidence that presence of carotid plaque, is associated with poorer cognitive function and brain health.

Parental Education and Adolescents' Asthma: The Role of Ethnicity

While high parental education is associated with better health, this association may be weaker for ethnic minority than for ethnic majority families. It is unknown whether the association between parental education and adolescents' asthma also varies by ethnicity.

AIM

To study the association between parental education and adolescents' asthma overall and by ethnicity.

METHODS

The current study used data from the Population Assessment of Tobacco and Health (PATH)-Adolescents study. All participants were 12 to 17-year-old non-smokers (n = 8652). The outcome of interest was adolescents' asthma. The predictor of interest was baseline parental education, the covariates were age, sex, and number of parents present at baseline, and the moderator was ethnicity.

RESULTS

According to logistic regression analyses, higher parental education was predictive of adolescents' asthma; however, this association was weaker for Latino than non-Latino adolescents (OR 1.771; CI 1.282-2.446). We did not find a significant difference in the effect of parental education on asthma of White and African American adolescents. Our stratified models also showed that higher parental education was associated with lower asthma for non-Latino but not for Latino adolescents.

CONCLUSION

The effect of high parental education on adolescents' asthma prevalence differs between Latino and non-Latino families, with Latino families showing weaker protective effects of parental education on adolescents' asthma. Future research should test the role of exposure to environmental pollutants, neighborhood quality, and prevalence of smoking in social network members as well as other contextual factors at home, in school, and in the neighborhood that may increase prevalence of asthma in Latino adolescents regardless of their parental education. Given that these potential causes are multi-level, potential causes of such disparities should be tested in future multi-level research.

Women with Myocardial Infarction Present Subtle Cognitive Difficulties on a Neuropsychological Battery After Exposure to a Social Stressor

Objective

Myocardial infarction (MI) is the primary cause of mortality and morbidity in women, but its sequelae remain largely understudied. Given the heart-brain relationship, our study aimed to further understand stress's impact on regulating cognitive function post-MI. Specifically, our study evaluated the effect of stress induced using the Trier Social Stress Test (TSST), on neuropsychological function in women who have or have not experienced MI.

Methodology

To do so, women (mean age = 59.41 yrs) with (WHx_MI = 13) or without () a history of MI were exposed to the TSST prior to completion of a series of standardized neuropsychological tests: the Montreal Cognitive Assessment (MoCA), Control Oral Word Association (COWA), Rey Complex Figure and Recognition (RCFT), Trail Making Test (TMT), and Auditory Consonant Triagrams (ACT).

Results

Our findings support MI to be associated with impairments in working memory affecting immediate recall of ACT, as well as visuospatial impairments in the RCFT copy trial, marked by poorer drawing accuracy and incorrect placement of figure elements. Overall, WHx_MI required more time to complete the neuropsychological assessment (WHx_MI 166.57 ± 12, 155.00 ± 6.57; p < 0.01).

Conclusion

Together, these findings support cognitive impairments noted following a social stressor to remain subtle in WHx_MI. Our study highlights the need for the development of more sensitive tools to screen for neuropsychological impairments in women with MI and the importance of assessing performance in a variety of testing conditions.

Is carotid artery atherosclerosis associated with poor cognitive function assessed using the Mini-Mental State Examination? A systematic review and meta-analysis

OBJECTIVES

To determine associations between carotid atherosclerosis assessed by ultrasound and the Mini-Mental State Examination (MMSE), a measure of global cognitive function.

DESIGN

Systematic review and meta-analysis.

METHODS

MEDLINE and EMBASE databases were searched up to 1 May 2020 to identify studies assessed the associations between asymptomatic carotid atherosclerosis and the MMSE. Studies reporting OR for associations between carotid plaque or intima-media thickness (cIMT) and dichotomised MMSE were meta-analysed. Publication bias of included studies was assessed.

RESULTS

A total of 31 of 378 reviewed articles met the inclusion criteria; together they included 27 738 participants (age 35-95 years). Fifteen studies reported some evidence of a positive association between measures of atherosclerosis and poorer cognitive performance in either cross-sectional or longitudinal studies. The remaining 16 studies found no evidence of an association. Seven cross-sectional studies provided data suitable for meta-analysis. Meta-analysis of three studies that assessed carotid plaque (n=3549) showed an association between the presence of plaque and impaired MMSE with pooled estimate for the OR (95% CI) being 2.72 (0.85 to 4.59). An association between cIMT and impaired MMSE was reported in six studies (n=4443) with a pooled estimate for the OR (95% CI) being 1.13 (1.04 to 1.22). Heterogeneity across studies was moderate to small (carotid plaque with MMSE, I2=40.9%; cIMT with MMSE, I2=4.9%). There was evidence of publication bias for carotid plaque studies (p=0.02), but not cIMT studies (p=0.2).

CONCLUSIONS

There is some, limited cross-sectional evidence indicating an association between cIMT and poorer global cognitive function assessed with MMSE. Estimates of the association between plaques and poor cognition are too imprecise to draw firm conclusions and evidence from studies of longitudinal associations between carotid atherosclerosis and MMSE is limited.

PROSPERO REGISTRATION NUMBER

CRD42021240077.

Intima Media Thickness and Cognitive Function Among Adults: Meta-Analysis of Observational and Longitudinal Studies

Background

Carotid structural changes measured by intima media thickness (IMT) have been related to cognitive complaints during aging. Therefore, the aims of this meta‐analysis were (1) to elucidate the relationship between vascular status, measured as IMT, and cognitive domains distinguishing between global cognition, executive functions, memory and attention; and (2) to explore whether demographic (ie, age and sex), clinical (ie, body mass index and IMT baseline values), and procedure characteristics influence this association.

Methods and Results

We performed a systematic review of MEDLINE (via PubMed), Scopus, and Web of Science databases from their inception to June 2021. Studies meeting the following inclusion criteria were included: (1) the participants were adults; (2) the exposure was carotid IMT; (3) the outcome was cognitive function, including global cognition, executive function, memory, and attention measured using standardized tests; and (4) the study design was cross‐sectional or longitudinal including unadjusted and adjusted analyses. A total of 19 cross‐sectional and 15 longitudinal studies were included and demographic (age and sex), clinical (body mass index and baseline IMT values), and procedure characteristics were analyzed as potential mediator or moderators of the association.

Conclusions

Our data support negative associations between IMT and cognitive function in cross‐sectional studies. The association between IMT and cognition lost significance in longitudinal studies and when controlling for covariates in cross‐sectional studies. Finally, the strength of these associations seems not to be modified by age, sex, body mass index, and baseline IMT values. This systematic review and meta‐analysis adds to the evidence supporting the use of IMT as a measure for identifying patients at risk of cognitive decline.

Neuropsychological Sequelae of Coronary Heart Disease in Women: A Systematic Review

Heart disease, such as coronary heart disease (CHD), is the leading cause of death among aging women. However, over the past years, the mortality rate has declined, resulting in an increased number of CHD survivors. In this context, research has uncovered relationships between cardiovascular disease (CVD) and the development of neurodegenerative diseases, suggesting that CHD can act as a precursor. Despite heart disease affecting both sexes, CVD research has significantly neglected women. Therefore, we conducted the first systematic review of neuropsychological sequelae of CHD in women to gain a clear portrait of the current knowledge of the association of CHD on women's neuropsychological status. We found that studies continue to include an insufficient number of women in their research. Our work also uncovered that there is variability in the definition of CHD by researchers (i.e., operationalization of the variable), which could explain inconsistencies across studies. Overall, we found evidence that supports the heart-brain disease hypothesis. To conclude, we provide several guidelines for future research involving the impact of CHD in women.

Body Mass Index, Height and Socioeconomic Position in Adolescence, Their Trajectories into Adulthood, and Cognitive Function in Midlife

BACKGROUND

Whether life course anthropometric indices relate to cognitive function in midlife remains insufficiently explored. Rarely was socioeconomic position (SEP) adequately accounted for.

OBJECTIVE

To examine the association of the cumulative life course burden of high-ranked body mass index (BMI), its trajectory, and stature with cognitive function in midlife.

METHODS

Weight and height were measured from age 17 across a 33-year follow-up. 507 individuals completed a NeuroTrax computerized cognitive assessment at ages 48-52. Life course SEP was assessed by multiple methods. Using mixed models we calculated the area under the curve (AUC), representing both the life-course burden of BMI (total AUC) and trends in BMI (incremental AUC) from age 17 to midlife. The associations of BMI and height with global cognition and its five component domains were assessed by multiple regression.

RESULTS

Higher BMI in late adolescence and total AUC over the life course were associated with poorer global cognition (Standardized beta (Beta) = -0.111, p = 0.005 and Beta = -0.105, p = 0.018, respectively), adjusted for childhood and adulthood SEP, and demographic characteristics. The associations with higher adolescent and midlife BMI were both restricted to those with low childhood SEP (p < 0.05 for interaction). Short adolescent stature was related to poorer cognition (Beta = 0.115, p = 0.040), whereas late final growth in women was associated with better cognition (Beta = 0.213, p = 0.007).

CONCLUSION

An adverse association of higher BMI with cognitive function began in adolescence and was restricted to low childhood SEP. Taller stature in both sexes and late growth in women were associated with better midlife cognitive performance.

Nonlinear associations between plasma cholesterol levels and neuropsychological function

OBJECTIVE

Although both high and low levels of total and low-density lipoprotein (LDL) cholesterol have been associated with poor neuropsychological function, little research has examined nonlinear effects. We examined quadratic relations of cholesterol to performance on a comprehensive neuropsychological battery.

METHOD

Participants were 190 older adults (53% men, ages 54-83) free of major medical, neurologic, and psychiatric disease. Measures of fasting plasma total and high-density lipoprotein (HDL) cholesterol were assayed, and LDL cholesterol was calculated. Participants completed neuropsychological measures of attention, executive function, memory, visuospatial judgment, and manual speed and dexterity. Multiple regression analyses examined cholesterol levels as quadratic predictors of each measure of cognitive performance, with age (dichotomized as <70 vs. 70+) as an effect modifier.

RESULTS

A significant quadratic effect of Total Cholesterol² × Age was identified for Logical Memory II (b = -.0013, p = .039), such that the 70+ group performed best at high and low levels of total cholesterol than at midrange total cholesterol (U-shaped) and the <70 group performed worse at high and low levels of total cholesterol than at midrange total cholesterol (inverted U shape). Similarly, significant U- and J-shaped effects of LDL Cholesterol² × Age were identified for Visual Reproduction II (b = -.0020, p = .026) and log of the Trail Making Test, Part B (b = .0001, p = .044). Quadratic associations between HDL cholesterol and cognitive performance were nonsignificant.

CONCLUSIONS

Results indicate differential associations between cholesterol and neuropsychological function across different ages and domains of function. High and low total and LDL cholesterol may confer both risk and benefit for suboptimal cognitive function at different ages. (PsycINFO Database Record

Subclinical carotid atherosclerosis and neurocognitive function in an urban population

BACKGROUND AND AIMS

Examine age, sex, race, and socioeconomic status as modifiers of the association between carotid intimal medial thickness (IMT) and neurocognitive performance in a socioeconomically diverse, biracial, urban, adult population.

METHODS

Participants were 1712 community-dwelling adults (45% men, 56% African-American, 38% below poverty threshold, aged 30-64 years) enrolled in the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Participants underwent initial carotid ultrasonography followed by cognitive testing on up to two occasions over 4 years. Mixed-effects regression analyses were adjusted for demographic, behavioral, and biomedical covariates.

RESULTS

Significant cross-sectional IMT × race × poverty interactions were identified for measures of delayed recall memory, auditory-verbal attention, and working memory. An IMT × race interaction also appeared for auditory-verbal learning. Higher IMT was generally associated with worse cognitive performance, but the disadvantage was most pronounced among those with higher socioeconomic status and white participants. No longitudinal associations were identified.

CONCLUSIONS

Carotid IMT-cognition associations differed as a function of race and socioeconomic status and were most compelling for measures of attention, executive function, and memory. These findings highlight the possibility that subclinical atherosclerosis may be differentially informative as a predictor of cognitive performance among varied demographic subgroups.

Association between Carotid Artery Stenosis and Cognitive Impairment in Stroke Patients: A Cross-Sectional Study

To investigate potential associations between carotid artery stenosis and cognitive impairment among patients with acute ischemic stroke and to provide important clinical implications. We measured the degree of carotid artery stenosis and recorded the Mini-Mental State Examination score (MMSE) at admission in 3116 acute ischemic stroke patients. The association between carotid stenosis and cognitive impairment assessed by MMSE was tested using multivariate regression analysis. Other clinical variables of interest were also studied. After adjusting for age, gender, education level, marriage, alcohol use, tobacco use, physical activity, hypertension, diabetes, hypercholesterolemia, atrial fibrillation, myocardial infarction and NIHSS (National Institutes of Health Stroke Scale) score, we found that participants with high-grade stenosis of the carotid artery had a higher likelihood of cognitive impairment compared to those without carotid artery stenosis (OR = 1.49, 95%CI: 1.05–2.11, p<0.001). Left common carotid artery stenosis was associated with cognitive impairment in the univariate analysis, although this effect did not persist after adjustment for the NIHSS score. Cognitive impairment was associated with high-grade stenosis of the right carotid artery.

Intima-Media Thickness and Cognitive Function in Stroke-Free Middle-Aged Adults: Findings From the Coronary Artery Risk Development in Young Adults Study

BACKGROUND AND PURPOSE

The relationship between carotid artery intima-media thickness (IMT) and cognitive function in midlife remains relatively unexplored. We examined the association between IMT and cognitive function in a middle-aged epidemiological cohort of 2618 stroke-free participants.

METHODS

At the year 20 visit (our study baseline), participants from the Coronary Artery Risk Development in Young Adults study had IMT measured by ultrasound at the common carotid artery. Five years later, participants completed a cognitive battery consisting of the Rey Auditory-Verbal Learning Test of verbal memory, the Digit Symbol Substitution Test of processing speed, and the Stroop test of executive function. We transformed cognitive scores into standardized z scores, with negative values indicating worse performance.

RESULTS

Mean age at baseline was 45.3 years (SD, 3.6). Greater IMT (per 1 SD difference of 0.12 mm) was significantly associated with worse performance on all cognitive tests (z scores) in unadjusted linear regression models (verbal memory, -0.16; 95% confidence interval [CI], -0.20 to -0.13; processing speed, -0.23; 95% CI, -0.27 to -0.19; and executive function, -0.17; 95% CI, -0.20 to -0.13). In models adjusted for sociodemographics and vascular risk factors that lie earlier in the causal pathway, greater IMT remained negatively associated with processing speed (-0.06; 95% CI, -0.09 to -0.02; P, 0.003) and borderline associated with executive function (-0.03; 95% CI, -0.07 to 0.00; P, 0.07) but not with verbal memory.

CONCLUSIONS

We observed an association between greater IMT and worse processing speed-a key component of cognitive functioning-at middle age above and beyond traditional vascular risk factors. Efforts targeted at preventing early stages of atherosclerosis may modify the course of cognitive aging.

Cardiovascular risk score, cognitive decline, and dementia in older Mexican Americans: the role of sex and education

Background

The purpose of this study was to examine the associations of cardiovascular disease (CVD) risk with cognitive decline and incidence of dementia and cognitive impairment but not dementia (CIND) and the role of education as a modifier of these effects.

Methods and Results

One thousand one hundred sixteen Mexican American elderly were followed annually in the Sacramento Area Latino Study on Aging. Our sex‐specific 10‐year CVD risk score included baseline age, systolic blood pressure, total cholesterol, high‐density lipoprotein, smoking, body mass index, and diabetes. From adjusted linear mixed models, errors on the Modified Mini–Mental State Exam (3MSE) were annually 0.41% lower for women at the 25th percentile of CVD risk, 0.11% higher at the 50th percentile, and 0.83% higher at the 75th percentile (P value of CVDrisk×time <0.01). In men, 3MSE errors were annually 1.76% lower at the 25th percentile of CVD risk, 0.96% lower at the 50th percentile, and 0.12% higher at the 75th percentile (P value of CVDrisk×time <0.01). From adjusted linear mixed models, the annual decrease in the Spanish and English Verbal Learning Test score was 0.09 points for women at the 25th percentile of CVD risk, 0.10 points at the 50th percentile, and 0.12 points at the 75th percentile (P value of CVDrisk×time=0.02). From adjusted Cox models in women, compared with having <6 years of education, having 12+ years of education was associated with a 76% lower hazard of dementia/CIND (95% CI, 0.08 to 0.71) at the 25th percentile of CVD risk and with a 45% lower hazard (95% CI, 0.28 to 1.07) at the 75th percentile (P value of CVDrisk×education=0.05).

Conclusions

CVD risk score may provide a useful tool for identifying individuals at risk for cognitive decline and dementia.

Carotid atherosclerosis and 10-year changes in cognitive function

BACKGROUND

Carotid atherosclerosis has been suggested to be involved in cognitive decline.

METHODS

The Epidemiology of Hearing Loss Study is a longitudinal study of aging among Beaver Dam residents, WI. In 1998-2000, carotid intima-media thickness (IMT) and plaque were measured by ultrasound; cognitive function was measured by the Mini-Mental State Examination (MMSE). Follow-up examinations were conducted in 2003-2005 and 2009-2010. Incidence of cognitive impairment was defined as an MMSE score <24 or reported physician-diagnosed dementia during the follow-up. In the last examination, five additional cognitive tests were added. The associations of carotid atherosclerosis with incident cognitive impairment and cognitive test performance ten years later were evaluated.

RESULTS

A total of 1651 participants (mean age 66.8 years, 41% men) without cognitive impairment at baseline were included in the incidence analysis. IMT was associated with incidence of cognitive impairment after multiple adjustments (hazard ratio: 1.09, p = 0.02 for each 0.1 mm increase in IMT). A total of 1311 participants with atherosclerosis data at baseline had the additional cognitive tests 10 years later. Larger IMT was associated with longer time to complete the Trail-Making Test-part B after multiple adjustments (0.1 mm IMT: 2.3 s longer, p = 0.02). Plaque was not associated with incident cognitive impairment or cognitive test performance 10 years later.

CONCLUSIONS

In this population-based longitudinal study, carotid IMT was associated with a higher risk of developing cognitive impairment during the 10-year follow-up, and was associated with poorer performance in a test of executive function 10 years later.

Carotid atherosclerosis and cognitive function in midlife: the Beaver Dam Offspring Study

BACKGROUND

Atherosclerosis may be associated with cognitive function; however the studies are few, especially among midlife adults.

METHODS

Participants in the beaver dam offspring study who had cognitive test data and gradable carotid artery ultrasound scans were included (n=2794, mean age: 49 years). Atherosclerosis was measured by carotid intima-media thickness (IMT) and the presence of plaque. Cognitive function was measured by the trail making test (TMT), grooved pegboard test (GPT) and mini-mental state examination (MMSE). Generalized cognitive function was defined by a summary score calculated from the TMT and GPT. Linear regression was used to evaluate the associations between carotid atherosclerosis and cognitive function tests.

RESULTS

Larger IMT was associated with lower GPT, MMSE and the summary score adjusting for multiple factors, the coefficients were: 13.8s (p<0.0001), -0.6 (p=0.007), and 0.47 (p=0.01), respectively for 1mm increase in IMT. Plaque scores were significantly associated with TMT-B, GPT, MMSE, and the summary score adjusting for age, sex and education. The associations remained statistically significant after further adjustments except for the association with TMT-B, which was attenuated and no longer significant.

CONCLUSIONS

Our results show the significant associations between markers of carotid atherosclerosis and cognitive function in a cohort of persons aged 21-84 years. Longitudinal studies are needed to further examine these associations.

High alcohol consumption in middle-aged adults is associated with poorer cognitive performance only in the low socio-economic group. Results from the GAZEL cohort study

AIMS

To examine the association of alcohol consumption over 10 years with cognitive performance in different socio-economic groups.

DESIGN

Prospective cohort study, the French GAZEL study.

SETTING

France.

PARTICIPANTS

Employees of France's national electricity and gas company.

MEASUREMENTS

Alcohol intake was assessed annually, beginning in 1992, using questions on frequency and quantity of alcoholic beverages consumed in a week; used to define mean consumption and trajectory of alcohol intake over 10 years. Cognitive performance among participants aged ≥ 55 years (n = 4073) was assessed in 2002-04 using the Digit Symbol Substitution Test (DSST), a measure of psychomotor speed, attention and reasoning. Occupational position at age 35 and education were used as the markers of socio-economic position.

FINDINGS

All analyses were stratified by socio-economic position. In the low occupational group, participants consuming a mean of more than 21 drinks per week had 2.1 points lower (95% CI: -3.9, -0.3) DSST score compared to those consuming four to 14 drinks per week. In participants with primary school education, the corresponding difference was 3.6 points (95% CI: -7.1, -0.0). No association between alcohol consumption and cognitive performance was observed in the intermediate and high socio-economic groups, defined using either occupation or education. Analysis of trajectories of alcohol consumption showed that in the low socio-economic groups large increase or decrease in alcohol consumption was associated with lower cognitive scores compared to stable consumption.

CONCLUSIONS

Our results suggest that high alcohol consumption is associated with poorer cognitive performance only in the low socio-economic group, due possibly to greater cognitive reserve in the higher socio-economic groups.

Metabolic syndrome over 10 years and cognitive functioning in late midlife: the Whitehall II study

OBJECTIVE

Evidence that the metabolic syndrome is a risk factor for poor cognition is mixed and is focused mainly on the elderly population; rarely is an adjustment made for socioeconomic factors. We examined this association in late midlife, with particular focus on cumulative effects and the role of socioeconomic circumstances.

RESEARCH DESIGN AND METHODS

Analyses were performed for 4,150 white participants from the Whitehall II study. Metabolic syndrome, using the National Cholesterol Education Program Adult Treatment Panel III criteria, was assessed three times over the 10-year follow-up (1991-2001). Cognitive function was assessed using a battery of six tests at the end of the follow-up.

RESULTS

After adjustment for demographic variables, health behaviors, and health status, participants with persistent metabolic syndrome (at least two of the three screenings) over the 10-year follow-up had lower cognitive performance than participants who never had metabolic syndrome. No significant differences in cognitive function were observed between participants with nonpersistent metabolic syndrome (one of the three screenings) and those who never had metabolic syndrome during the follow-up. Adjustment for adult occupational position attenuated this association by between 41 and 86%, depending on the measure of cognitive function. Adjustment for education had little effect.

CONCLUSIONS

Only persistent metabolic syndrome was associated with lower cognitive performance in late midlife. Adult occupational position but not education had a substantial impact on this association; these results highlight the importance of adult socioeconomic circumstances in identifying and targeting risk factors for cognitive aging.

Cognition and incident coronary heart disease in late midlife: The Whitehall II study

The purpose of this study was to investigate whether cognitive function in midlife predicts incident coronary heart disease (CHD), followed up over 6 years. Data on 5292 (28% women, mean age 55) individuals free from CHD at baseline were drawn from the British Whitehall II study. We used Cox regression to model the association between cognition and CHD in analyses adjusted for socio-demographic variables, cardiovascular risk factors and health behaviors. The results show a one standard deviation lower score on the "general" cognitive measure and measures of reasoning and vocabulary to be associated with elevated CHD risk. There was some evidence that these effects differed between high and low socioeconomic status (SES) groups with associations only seen in the low SES group. These results were not explained by threshold effects or by the different SES groups representing different parts of the cognitive test score distribution. Three other possible explanations of these results are discussed: sub clinical vascular disease drives the observed association but no effect is observed in the high SES group due to compensation provided by greater cognitive reserve, cognition is a marker of overall bodily integrity particularly in low-SES groups, and SES is a moderator of the association between cognition and CHD, because it marks a range of other risk factors.

Association between metabolic syndrome and depressive symptoms in middle-aged adults: results from the Whitehall II study

OBJECTIVE

Although it is possible that the association between depression and the metabolic syndrome is a "two-way street," the metabolic syndrome as a predictor of depression has been little investigated. We examined whether the metabolic syndrome is associated with the onset of depressive symptoms in a cohort of middle-aged British civil servants.

RESEARCH DESIGN AND METHODS

Analyses included 5,232 participants (41-61 years of age) from the Whitehall II prospective cohort study. Depressive symptoms were assessed in 1991-1993 and again 6 years later using the depression subscale from the 30-item General Health Questionnaire. Metabolic syndrome was assessed in 1991-1993, according to National Cholesterol Education Program criteria.

RESULTS

Presence of the metabolic syndrome was associated with an increased risk of future depressive symptoms, odds ratio 1.38 (95% CI 1.02-1.96) after adjustment for potential confounders. Of the five components, only central obesity, high triglyceride levels, and low HDL cholesterol levels predicted depressive symptoms. These components explained most of the association between the metabolic syndrome and the onset of depressive symptoms.

CONCLUSIONS

Our results suggest that the metabolic syndrome, in particular the obesity and dyslipidemia components, is predictive of depressive symptoms.

Education attenuates the association between dietary patterns and cognition

BACKGROUND/AIMS

Various foods have been shown to be associated with cognitive outcomes. As individual food items are not consumed in isolation, we examined the association between dietary patterns and cognitive function, with special attention to the role of education in this association.

METHODS

Analyses were carried out on 4,693 stroke-free white European participants of the Whitehall II study. Two dietary patterns were determined using principal component analysis: a 'whole food' and a 'processed food' pattern. Cognitive function was assessed using a battery of 5 tests.

RESULTS

After adjustment for demographic, behavioral and health measures, higher intake of 'whole food' diet was associated with lower and high consumption of 'processed food' with higher odds of cognitive deficit. However, adjustment for education significantly attenuated most of these associations.

CONCLUSIONS

Education, through its role as a powerful confounder, shapes the relationship between dietary patterns and cognitive deficit in a healthy middle-aged UK cohort.

The association between heart rate variability and cognitive impairment in middle-aged men and women. The Whitehall II cohort study

BACKGROUND

To examine the relationship between reduced heart rate variability (HRV) and cognitive function in middle-aged adults in the general population.

METHODS

HRV, in both time and frequency domains, and cognitive functioning were measured twice in 5,375 male and female participants of the UK Whitehall II study (mean ages = 55 and 61 years, respectively). Logistic regression was used to model associations between HRV and cognition [short-term verbal memory, reasoning (Alice Heim 4-I), vocabulary, phonemic and semantic fluency]. Cross-sectional associations were assessed at both waves, and longitudinal associations were measured as changes in cognition over the 5-year follow-up.

RESULTS

No consistent associations were found in men or women, either in the cross-sectional, prospective or the longitudinal analyses of declines in cognition.

CONCLUSION

Reduced cardiovascular autonomic function does not contribute to cognitive impairment in this middle-aged population. Further studies are needed to verify the potential role of HRV measures in predicting the degeneration of cognitive function at older ages.