Social gradient in the metabolic syndrome not explained by psychosocial and behavioural factors: evidence from the Copenhagen City Heart Study∗

Social determinants of inflammatory markers linking depression and type 2 diabetes among women: A scoping review

OBJECTIVE

Inflammation is implicated in the pathophysiology of depression and type 2 diabetes (T2D) and is linked to social determinants of health (SDoH) associated with socioeconomic disadvantage. The objective of this review is to identify and map the range of SDoHs associated with inflammation in depression, T2D, or their co-occurrence among women.

METHODS

PubMed, CINAHL, PsychINFO, and Web of Science were searched March-July 2023 to identify studies where 1) an SDoH was a predictor or independent variable, 2) depression or T2D was a clinical focus, 3) inflammatory markers were collected, and 4) analysis was specific to women. We used the National Institute on Minority Health and Health Disparities research framework to guide searching SDoHs, organize findings, and identify gaps.

RESULTS

Of the 1135 studies retrieved, 46 met criteria. Within the reviewed studies, the most used inflammatory measures were C-reactive protein, interleukin-6, and tumor necrosis factor-α, and the most studied SDoHs were early life stress and socioeconomic status. Individual and interpersonal-level variables comprised the bulk of SDoHs in the included studies, while few to no studies examined built environment (n = 6) or health system level (n = 0) factors. Disadvantageous SDoHs were associated with higher levels of inflammation across the included studies.

CONCLUSION

The scope and intersection of depression and T2D represent a syndemic that contributes to and results from socioeconomic inequities and disproportionately affects women. Simultaneous inclusion of social and inflammatory measures, particularly understudied SDoHs, is needed to clarify potent targets aimed at advancing health and equity.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Associations between social network properties and metabolic syndrome and the mediating effect of physical activity: findings from the Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort

INTRODUCTION

Social isolation and loneliness are positively associated with metabolic syndrome. However, the mechanisms by which social isolation affects metabolic syndrome are not well understood.

RESEARCH DESIGN AND METHODS

This study was designed as a cross-sectional study of baseline results from the Cardiovascular and Metabolic Diseases Etiology Research Center (CMERC) Cohort. We included 10 103 participants (8097 community-based low-risk participants, 2006 hospital-based high-risk participants) from the CMERC Cohort. Participants aged 65 years or older were excluded. Multiple imputation by chained equations was applied to impute missing variables. The quantitative properties of social networks were assessed by measuring the 'size of social networks'; qualitative properties were assessed by measuring the 'social network closeness'. Metabolic syndrome was defined based on the National Cholesterol Education Program Adult Treatment Panel III criteria. Multivariate logistic regression analyses were conducted to assess association between social network properties and metabolic syndrome. The mediating effects of physical inactiveness, alcohol consumption, cigarette smoking and depressive symptoms were estimated. Age-specific effect sizes were estimated for each subgroup.

RESULTS

A smaller social network was positively associated with higher prevalences of metabolic syndrome in all subgroups, except the high-risk male subgroup. There was no clear association between social network closeness and metabolic syndrome. In community-based participants, an indirect effect through physical activity was detected in both sexes; however, in hospital-based participants, no indirect effects were detected. Cigarette smoking, alcohol consumption and depression did not mediate the association. Age-specific estimates showed that the indirect effect through physical activity had a greater impact in older participants.

CONCLUSIONS

A smaller social network is positively associated with metabolic syndrome. This trend could be partially explained by physical inactivity, especially in older individuals.

Association between Periodontitis and Metabolic Syndrome in a Korean Nationally Representative Sample of Adults Aged 35-79 Years

This study aimed to evaluate the association between periodontitis and metabolic syndrome (MetS) and to investigate risk factors associated with MetS in Korean adults aged 35 to 79 years. Among individuals aged 35-79 years who participated in the Korea National Health and Nutrition Examination Survey 2013-2015, 8314 participants who completed the required examinations and questionnaires were included. Confounding variables related to demographic and socioeconomic status and systemic and oral health-related behaviors were age, gender, household income, education level, smoking, alcohol intake, physical activity, and frequency of daily toothbrushing. Of the 8314 participants, 32.2% were diagnosed with MetS. The prevalence of MetS was 26.6% and 41.6% in those without and with periodontitis, respectively. Among individuals with periodontitis, the prevalence of MetS was 44.3% in males and 36.9% in females. Compared to non-periodontitis, periodontitis was associated with MetS (adjusted OR = 1.422, 95% CI: 1.26-1.61). Age, frequency of daily toothbrushing, and periodontitis were associated with MetS in both males and females. While current smoking and alcohol intake more than twice a week were significantly associated with MetS in males, household income and education level were significantly associated with MetS in females. The findings suggest that periodontitis can be associated with MetS.

Socio-economics status and metabolic syndrome: A meta-analysis

OBJECTIVE

The metabolic syndrome (MetS) is responsible for an increased risk of type 2 diabetes, cardiovascular diseases and is associated with all-cause and cardiovascular mortality. Economic and social vulnerability is not an easy concept to grasp, but some studies investigate the association between MetS and socioeconomic and demographic factors, deprivation (more often correlations rather than causal one due to data). This work aims to assess the association between MetS and socio-economic gradient (SEG) in the literature by performing a meta-analysis.

DESIGN

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for systematic reviews were followed.

SETTING

The raw list of studies extracted from PubMed as regard to the inclusion/exclusion criteria was imported in Word. Studies were filed with regard to our three definitions of SEG and their title.

PARTICIPANTS

Subgroup analysis were performed considering several definitions of Mets: NCEP-ATPIII and IDF2006.

RESULTS

The overall multivariable-adjusted OR showed that the risk of MetS was significantly increased in association with SEG The results of the subgroup analysis showed an increased risk of MetS in association with SEG when IDF definition was considered.

CONCLUSIONS

Targeted interventions must be implemented in a specific way as prevention campaigns aimed at the general population are generally not adapted to this particular vulnerable population.

Salivary Biomarkers of Parenting Stress in Mothers Under Community Criminal Justice Supervision

BACKGROUND

Community criminal justice supervised mothers are an underserved population who experience high rates of psychological distress and unique parenting challenges, but little is known about physiological stress system function in this population.

OBJECTIVE

We tested the salivary biomarkers of the sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal (HPA) axis function as predictors of subjective maternal stress.

METHOD

We recruited 23 mothers (age: M = 35.6 years, SD = 9.3 years; 35% Hispanic, 22% Black, 22% White, 22% multiracial) who were court mandated to a residential treatment center. We measured salivary alpha-amylase (AA) and cortisol, which index SNS and HPA activity, respectively, before and after a naturalistic reminder of a stressful parenting experience. We assessed self-reported parenting stress using the Parenting Stress Index-Short Form (PSI-SF) subscales Parental Distress, Parent-Child Dysfunctional Interactions, and Difficult Child. We used regression to test AA and cortisol mean levels and reactivity as predictors of subscale scores.

RESULTS

Mean, but not reactive, salivary stress biomarker levels were associated with parenting stress domains. Mean cortisol levels predicted scores on the Parent-Child Dysfunctional Interaction subscale (adj. R = .48), whereas mean AA predicted Difficult Child subscale scores (adj. R = .28).

DISCUSSION

Our results demonstrate the potential predictive utility of AA and cortisol as salivary biomarkers of maternal stress in community-supervised mothers. Given that maternal stress is associated with criminal recidivism and child behavioral health in this population, these biomarkers could potentially inform interventions to improve dyadic health and social outcomes.

The contribution of health behaviors to socioeconomic inequalities in health: A systematic review

Unhealthy behaviors and their social patterning have been frequently proposed as factors mediating socioeconomic differences in health. However, a clear quantification of the contribution of health behaviors to the socioeconomic gradient in health is lacking. This study systematically reviews the role of health behaviors in explaining socioeconomic inequalities in health. Published studies were identified by a systematic review of PubMed, Embase and Web-of-Science. Four health behaviors were considered: smoking, alcohol consumption, physical activity and diet. We restricted health outcomes to cardiometabolic disorders and mortality. To allow comparison between studies, the contribution of health behaviors, or the part of the socioeconomic gradient in health that is explained by health behaviors, was recalculated in all studies according to the absolute scale difference method. We identified 114 articles on socioeconomic position, health behaviors and cardiometabolic disorders or mortality from electronic databases and articles reference lists. Lower socioeconomic position was associated with an increased risk of all-cause mortality and cardiometabolic disorders, this gradient was explained by health behaviors to varying degrees (minimum contribution -43%; maximum contribution 261%). Health behaviors explained a larger proportion of the SEP-health gradient in studies conducted in North America and Northern Europe, in studies examining all-cause mortality and cardiovascular disease, among men, in younger individuals, and in longitudinal studies, when compared to other settings. Of the four behaviors examined, smoking contributed the most to social inequalities in health, with a median contribution of 19%. Health behaviors contribute to the socioeconomic gradient in cardiometabolic disease and mortality, but this contribution varies according to population and study characteristics. Nevertheless, our results should encourage the implementation of interventions targeting health behaviors, as they may reduce socioeconomic inequalities in health and increase population health.

Does vital exhaustion increase the risk of type 2 diabetes? A prospective study

BACKGROUND

There is evidence that both stress and depression have a causal relationship with type 2 diabetes suggesting that vital exhaustion (VE) too could be a risk factor. The association between VE and type 2 diabetes has, however, not been investigated prospectively.

AIM

To prospectively investigate whether VE is associated with an increased risk of type 2 diabetes in a Danish population.

METHODS

A prospective cohort study based on the Copenhagen City Heart Study (1991-1993). The degree of VE was measured among 9075 participants without type 1 or 2 diabetes at baseline. To detect type 2 diabetes in the follow-up period, two different approaches were used: In the first substudy, type 2 diabetes was defined based on blood samples and questionnaires from a follow-up study in 2001-2003 (N=4708). The second substudy was register-based, and the study population was linked to the Danish Hospital Discharge Register to detect registrations with type 2 diabetes until 2014.

RESULTS

A high degree of VE was associated with an increased risk of developing type 2 diabetes in both substudies. In the first substudy, the OR for developing type 2 diabetes was 2.56 (95% CI, 1.53; 4,29, P<0,001) among the quartile of participants reporting the highest degree of VE. In the second substudy, the OR was 1.31 (95% CI, 0.99; 1.72, P=0.053) for this group.

CONCLUSION

The results indicate that VE may be a useful measure in clinical practice in order to discover individuals at risk of type 2 diabetes.

Individual and regional association between socioeconomic status and uncertainty stress, and life stress: a representative nationwide study of China

BACKGROUND

Many studies have examined the association between socioeconomic status (SES) and mental stress. Uncertainty stress is a prominent aspect of mental stress. Yet no research has ever empirically analyzed the impact of SES on uncertainty stress.

METHODS

Students were identified through a multistage survey sampling process including 50 universities. Each student participant completed the Global Health Professions Student Survey (GHPSS) on Tobacco Control in China. Regional variables were retrieved from the National Bureau of Statistics database. Both unadjusted and adjusted methods were considered in the analyses.

RESULTS

Among the 11,942 participants, severe uncertainty stress prevalence was 19.6%, while severe life stress prevalence was 8.6%. Multilevel logistic regression showed that most SES variables were associated with uncertainty stress. Students with "operation and commercial work" as mother's occupation and "rural or township" as family location exhibited a higher prevalence of severe uncertainty stress. Lower family income and original region gross domestic products (GDP) were also associated with higher severe uncertainty stress prevalence. However, only father's occupation was correlated with life stress.

CONCLUSIONS

Based on the literature review, this is the first empirical study examining the impact of SES on uncertainty stress in China and elsewhere in the world. Our research underscores the importance of decreasing socioeconomic inequalities in controlling excessive uncertainty stress.

Cardiometabolic and Inflammatory Biomarkers as Mediators Between Educational Attainment and Functioning at the Age of 90 Years

BACKGROUND

Low socioeconomic status is associated both with poorer functioning and elevated levels of inflammatory and cardiometabolic biomarkers; however, knowledge of such relations for the oldest old is limited. Our aim was to study whether education is associated with cardiometabolic (cholesterol levels, body mass index, and leptin) and inflammatory (C-reactive protein, interleukin-6, interleukin-1Ra) biomarkers for the 90-year-olds who participated in the Vitality 90+ study. In addition, we investigated whether these biomarkers explain educational inequalities in functioning.

METHODS

All persons in Tampere, Finland, who were born in 1909 or 1910, were invited to participate, irrespective of their health status or dwelling place. The sample consisted of 262 participants who went through the home interview and blood tests. The socioeconomic status indicator used was the highest education, and physical functioning was assessed using the Barthel index. The association of education with individual and combined biomarker scores, and with functioning, was analyzed cross-sectionally applying generalized linear models.

RESULTS

The low- and mid-level-educated participants had greater odds of belonging to the high risk group in cardiometabolic biomarkers than did the high-educated. Differences were statistically significant in three individual biomarkers (high-density lipoprotein-cholesterol, leptin, and body mass index) and in a cardiometabolic score. There were no educational differences in inflammatory biomarkers. When all biomarkers were combined, they mediated educational differences in functioning on an average of 23%. After controlling for smoking, alcohol use and diseases, biomarkers mediated part of the differences between the mid-level- and high-educated.

CONCLUSIONS

High education was associated with better cardiometabolic biomarkers and functioning among the 90-year-olds. In part, educational inequalities in functioning were explained by cardiometabolic biomarkers.

Socio-demographic factors and the prevalence of metabolic syndrome among filipinos from the LIFECARE cohort

BACKGROUND

Metabolic syndrome(MetS) is an aggregation of multiple metabolic risk factors shown to lead to the development of cardiovascular disease. The International Diabetes Federation(IDF) and the modified National Cholesterol Education Program Adult Treatment Panel Ⅲ(mNCEP) criteria are used in identifying MetS. This report will determine the prevalence of MetS and its component risk factors of the Philippine cohort of the LIFE course study in CARdiovascular disease Epidemiology(LIFECARE).

METHODS

Our study recruited 3,072 participants aged 20-50 years old from Metro Manila and four nearby provinces. Baseline anthropometric and clinical parameters were measured. Prevalence of MetS and its component factors were determined. Associations with socio-demographic factors were determined.

RESULTS

The prevalence of MetS was 19.7% and 25.6% by IDF and mNCEP, respectively(kappa 0.83). Both were associated with increasing age, urban residence, and employed status. It was higher in females by IDF and in males by mNCEP. IDF missed 40% of males and 10% of females identified with MetS by mNCEP. More males were identified by the mNCEP as MetS despite relatively normal waist circumference.

CONCLUSION

MetS is common in the Philippines among older, educated, and urban residents. The mNCEP criteria identified more MetS than the IDF criteria.

Association between socioeconomic status and obesity in adults: evidence from the 2001 to 2009 Korea national health and nutrition examination survey

Objectives

The present study examined relationships between socioeconomic status (SES) and obesity and body mass index (BMI) as well as the effects of health-related behavioral and psychological factors on the relationships.

Methods

A cross-sectional population-based study was conducted on Korean adults aged 20 to 79 years using data from the 2001, 2005, and 2007 to 2009 Korea National Health and Nutrition Examination Survey. Multivariate logistic and linear regression models were used to estimate odds ratios of obesity and mean differences in BMI, respectively, across SES levels after controlling for health-related behavioral and psychological factors.

Results

We observed significant gender-specific relationships of SES with obesity and BMI after adjusting for all covariates. In men, income, but not education, showed a slightly positive association with BMI (p<0.05 in 2001 and 2005). In women, education, but not income, was inversely associated with both obesity and BMI (p<0.0001 in all datasets). These relationships were attenuated with adjusting for health-related behavioral factors, not for psychological factors.

Conclusions

Results confirmed gender-specific disparities in the associations of SES with obesity and BMI among adult Korean population. Focusing on intervention for health-related behaviors may be effective to reduce social inequalities in obesity.

Health promotion in the Danish maritime setting: challenges and possibilities for changing lifestyle behavior and health among seafarers

BACKGROUND

Seafaring is a risky occupation when compared to land-based industries as incidence rates of mortality and morbidity are higher. This trend is partly due to a higher number of accidents but also higher incidence of lifestyle-related diseases like cardiovascular disease and lung cancer. In Denmark, the proportion of smokers as well as of overweight and obese persons is higher among seafarers compared to the general population. This high burden of risk indicates that this occupational group might be a growing challenge at sea in regard to safety and health issues and there is a need to further our understanding of the health promotion approaches that work.

METHODS

A single-group pre-post design was conducted in 2008-2009 in order to identify changes in lifestyle related behaviors and health risk factors among seafarers (N: 606) in two Danish shipping companies after implementing two structural health promotion interventions (healthy cooking courses for ship cooks and improvement of fitness facilities) as well as health education interventions (smoking cessation courses, individual exercise guidance and extra health check-ups) at the maritime workplace. Baseline and follow-up data were collected with a self-administrated standardized questionnaire and individual health profiling assessing parameters such as physical health and physical fitness. In addition, qualitative interviews with participants and non-participants were conducted in order to gain in-depth information on experiences with the intervention processes.

RESULTS

Significant changes were identified for levels of fitness, daily sugar intake and metabolic syndrome. However, these results were not associated with participating in the health educational interventions. One possible explanation for the improved fitness rate could be the upgrading of fitness equipment onboard the ships provided by the management level. The decrease in daily sugar intake and prevalence of seafarers with metabolic syndrome might be associated with the cooking course intervention which aimed at providing healthier daily meals on board.

CONCLUSION

The findings suggest that a multicomponent health promotion intervention program has the potential to achieve change in seafarers' health behavior and health parameters. In the future, studies with more rigorous designs, separately testing the contribution of different types of interventions are needed.

The influence of sex and age on the relationship between sleep duration and metabolic syndrome in Korean adults

AIMS

To investigate the influence of sex and age on the relationship between sleep duration and metabolic syndrome in a nationally representative population.

METHODS

We used data from the Korea National Health and Nutrition Examination Survey (2001-2010) and enrolled 24,511 participants aged 20-79 years. Sleep duration was categorized into five groups: ≤5, 6, 7 (referent), 8, and ≥9h/day. Age was categorized into three groups: younger (20-39y), middle-aged (40-59y), and older (60-79y). The association between sleep duration and metabolic syndrome was assessed in the total, separately in men and women, then in six groups based on sex and age.

RESULTS

The prevalence of metabolic syndrome by sleep category demonstrated a U-shaped pattern in the total population. However, after adjusting for age, education, occupation, exercise, smoking, alcohol, and body mass index, the prevalence of metabolic syndrome increased in long sleepers (OR 1.31; 95% CI 1.14-1.51) but not in short sleepers (OR 1.00; 95% CI 0.89-1.11). The relationship between sleep duration and metabolic syndrome varied by sex and age-long sleep (≥9h/day) was positively associated with metabolic syndrome only in younger (OR 2.13; 95% CI 1.38-3.28) and middle-aged (OR 1.63; 95% CI 1.21-2.21) women. Short sleep (≤5h/day) was not associated with metabolic syndrome in any sex and age groups. However, extremely short sleep (≤4h/day) was associated with metabolic syndrome in middle-aged men (OR 1.76, 95% CI 1.05-2.96).

CONCLUSION

These data suggest that sex and age significantly modify the relationship between sleep duration and metabolic syndrome.

A risky occupation? (Un)healthy lifestyle behaviors among Danish seafarers

Sedentary working conditions, smoking, unhealthy eating habits and lack of exercise are some of the lifestyle risk factors that form a potentially growing problem for seafarers within certain parts of the maritime sector creating a heightened risk for chronic diseases such as diabetes and cardiovascular disease. Health promotion initiatives to combat this negative development requires as a first step identifying the magnitude of the different risk factors. A survey was conducted in 2007-08 with two Danish shipping companies on seafarers' health, wellbeing, diet, smoking and physical activity. In addition, a health profile was offered to the respondents, consisting of physiological measurements, such as fitness rating, body mass index (BMI), cholesterol measurement and blood pressure. The response rate in the questionnaire study was 57% (n = 360) of which 76% (n = 272) of the respondents received a health profile. Results (males) showed 44% daily smokers compared with 32% in the general Danish adult male population. Twenty-five percent of the seafarers were obese with a BMI > 30 compared with 12% of the Danish adult male population. Fifty-one percent of the respondents were defined as having metabolic syndrome, compared with 20% of the Danish adult male population. Seafaring is a risky occupation when looking at the seafarers' health and wellbeing. The results of this survey confirm the need for health promotion interventions such as smoking cessation courses, healthy cooking courses and physical exercise programs, etc. that can enable healthier lifestyle. The challenge will be to take into account the special seafaring conditions when implementing the interventions.

The contribution of stress to the social patterning of clinical and subclinical CVD risk factors in African Americans: the Jackson Heart Study

It is often hypothesized that psychosocial stress may contribute to associations of socioeconomic position (SEP) with risk factors for cardiovascular disease (CVD). However, few studies have investigated this hypothesis among African Americans, who may be more frequently exposed to stressors due to social and economic circumstances. Cross-sectional data from the Jackson Heart Study (JHS), a large population-based cohort of African Americans, were used to examine the contributions of stressors to the association of SEP with selected cardiovascular (CVD) risk factors and subclinical atherosclerotic disease. Among women, higher income was associated with lower prevalence of hypertension, obesity, diabetes and carotid plaque and lower levels of stress. Higher stress levels were also weakly, albeit positively, associated with hypertension, diabetes, and obesity, but not with plaque. Adjustment for the stress measures reduced the associations of income with hypertension, diabetes and obesity by a small amount that was comparable to, or larger, than the reduction observed after adjustment for behavioral risk factors. In men, high income was associated with lower prevalence of diabetes and stressors were not consistently associated with any of the outcomes examined. Overall, modest mediation effects of stressors were observed for diabetes (15.9%), hypertension (9.7%), and obesity (5.1%) among women but only results for diabetes were statistically significant. No mediation effects of stressors were observed in men. Our results suggest that stressors may partially contribute to associations of SEP with diabetes and possibly hypertension and obesity in African American women. Further research with appropriate study designs and data is needed to understand the dynamic and interacting effects of stressors and behaviors on CVD outcomes as well as sex differences in these effects.

Substance use, gender, socioeconomic status and metabolic syndrome among adults in Taiwan

OBJECTIVES

This study had two purposes: (1) To explore the mediating effects of substance use-as indicated by alcohol consumption, cigarette smoking, and betel-nut chewing-on the relationship between socioeconomic status (SES) and metabolic syndrome; and (2) to examine the way gender moderates any mediating effects of substance use.

DESIGN AND SAMPLE

Secondary analyses were conducted on a cross-sectional national dataset. The data from 3,107 males and 3,081 females of Taiwanese were analyzed.

MEASURES

The prevalence of metabolic syndrome, education level, occupation, age, body weight, body height, and behaviors were collected.

RESULTS

In male subjects, SES had no direct effect on metabolic syndrome; however, cigarette smoking and betel-nut chewing, but not alcohol consumption, were found to have mediating effects on SES and metabolic syndrome. In females, SES was found to have a direct effect on metabolic syndrome; however, substance use had no mediating effects on the relationship between SES and metabolic syndrome. These differences, in males and females indicated that the mediating effect of substance use on the relationship between SES and metabolic syndrome is moderated by gender.

CONCLUSIONS

Our study suggests that health care providers may need to provide gender-specific health promotion programs to prevent metabolic syndrome.

Trends in cardiovascular disease biomarkers and their socioeconomic patterning among adults in the Scottish population 1995 to 2009: cross-sectional surveys

OBJECTIVES

To examine secular and socioeconomic changes in biological cardiovascular disease risk factor and biomarker prevalences in the Scottish population. This could contribute to an understanding of why the decline in coronary heart disease mortality in Scotland has recently stalled along with persistence of associated socioeconomic inequalities.

DESIGN

Cross-sectional surveys.

SETTING

Scotland.

PARTICIPANTS

Scottish Health Surveys: 1995, 1998, 2003, 2008 and 2009 (6190, 6656, 5497, 4202 and 4964 respondents, respectively, aged 25-64 years).

PRIMARY OUTCOME MEASURES

Gender-stratified, age-standardised prevalences of obesity, hypertension, hypercholesterolaemia and low high-density lipoprotein cholesterol blood concentration as well as elevated fibrinogen and C reactive protein concentrations according to education and social class groupings. Inequalities were assessed using the slope index of inequality, and time trends were assessed using linear regression.

RESULTS

The prevalence of obesity, including central obesity, increased between 1995 and 2009 among men and women, irrespective of socioeconomic position. In 2009, the prevalence of obesity (defined by body mass index) was 29.8% (95% CI 27.9% to 31.7%) for men and 28.2% (26.3% to 30.2%) for women. The proportion of individuals with hypertension remained relatively unchanged between 1995 and 2008/2009, while the prevalence of hypercholesterolaemia declined in men from 79.6% (78.1% to 81.1%) to 63.8% (59.9% to 67.8%) and in women from 74.1% (72.6% to 75.7%) to 66.3% (62.6% to 70.0%). Socioeconomic inequalities persisted over time among men and women for most of the biomarkers and were particularly striking for the anthropometric measures when stratified by education.

CONCLUSIONS

If there are to be further declines in coronary heart disease mortality and reduction in associated inequalities, then there needs to be a favourable step change in the prevalence of cardiovascular disease risk factors. This may require radical population-wide interventions.

Bidirectional association between depression and metabolic syndrome: a systematic review and meta-analysis of epidemiological studies

OBJECTIVE

Epidemiological studies have repeatedly investigated the association between depression and metabolic syndrome (MetS). However, the results have been inconsistent. This meta-analysis aimed to summarize the current evidence from cross-sectional and prospective cohort studies that evaluated this association.

RESEARCH DESIGN AND METHODS

MEDLINE, EMBASE, and PsycINFO databases were searched for articles published up to January 2012. Cross-sectional and cohort studies that reported an association between the two conditions in adults were included. Data on prevalence, incidence, unadjusted or adjusted odds ratio (OR), and 95% CI were extracted or provided by the authors. The pooled OR was calculated separately for cross-sectional and cohort studies using random-effects models. The I(2) statistic was used to assess heterogeneity.

RESULTS

The search yielded 29 cross-sectional studies (n = 155,333): 27 studies reported unadjusted OR with a pooled estimate of 1.42 (95% CI 1.28-1.57; I(2) = 55.1%); 11 studies reported adjusted OR with depression as the outcome (1.27 [1.07-1.57]; I(2) = 60.9%), and 12 studies reported adjusted OR with MetS as the outcome (1.34 [1.18-1.51]; I(2) = 0%). Eleven cohort studies were found (2 studies reported both directions): 9 studies (n = 26,936 with 2,316 new-onset depression case subjects) reported adjusted OR with depression as the outcome (1.49 [1.19-1.87]; I(2) = 56.8%), 4 studies (n = 3,834 with 350 MetS case subjects) reported adjusted OR with MetS as the outcome (1.52 [1.20-1.91]; I(2) = 0%).

CONCLUSIONS

Our results indicate a bidirectional association between depression and MetS. These results support early detection and management of depression among patients with MetS and vice versa.

Socioeconomic status, psychosocial resources and risk, and cardiometabolic risk in Mexican-American women

OBJECTIVES

The current study examined the contributions of psychosocial factors to the association between socioeconomic status (SES) and metabolic syndrome (MetSyn) risk, in a randomly selected community cohort of 304 middle-aged (40-65 years old) Mexican-American women, a population at elevated cardiometabolic risk.

METHODS

Participants underwent a clinical exam and measures of demographic factors and psychosocial resource (i.e., personal and social resources) and risk (i.e., negative emotions and cognitions) variables. Confirmatory factor analysis (CFA) and structural equation models (SEMs) were performed in the total sample and in more- and less-U.S.-acculturated women (defined by language preference) separately.

RESULTS

CFAs revealed single latent constructs for SES (i.e., income, education) and psychosocial resources/risk. Three-factor solution was identified, with blood pressure (systolic diastolic), lipids (high-density lipoprotein cholesterol triglycerides), and metabolic variables (glucose waist circumference) forming separate factors. SEMs showed that an indirect effects model with SES relating to MetSyn factors through psychosocial resources/risk provided a reasonable descriptive and statistical fit in the full and more-acculturated sample (root mean square error of approximation [RMSEA] and standardized root-mean-square residual < .08); fit in the less-acculturated sample was marginal according to RMSEA = .09. A significant mediated path from low SES to higher waist circumference/fasting glucose via lower psychosocial resources/higher psychosocial risk was identified in the overall and more-acculturated samples (p < .05).

CONCLUSIONS

In this cohort of healthy, middle-aged Mexican-American women, contributions of psychosocial factors to SES-MetSyn associations were limited to the core underlying metabolic mechanisms, and to more-U.S.-acculturated women.

Psychological perspectives on pathways linking socioeconomic status and physical health

Low socioeconomic status (SES) is a reliable correlate of poor physical health. Rather than treat SES as a covariate, health psychology has increasingly focused on the psychobiological pathways that inform understanding why SES is related to physical health. This review assesses the status of research that has examined stress and its associated distress, and social and personal resources as pathways. It highlights work on biomarkers and biological pathways related to SES that can serve as intermediate outcomes in future studies. Recent emphasis on the accumulation of psychobiological risks across the life course is summarized and represents an important direction for future research. Studies that test pathways from SES to candidate psychosocial pathways to health outcomes are few in number but promising. Future research should test integrated models rather than taking piecemeal approaches to evidence. Much work remains to be done, but the questions are of great health significance.

Selection bias in a population survey with registry linkage: potential effect on socioeconomic gradient in cardiovascular risk

Non-participation in population studies is likely to be a source of bias in many types of epidemiologic studies, including those describing social disparities in health. The objective of this paper is to present a non-attendance analysis evaluating the possible impact of selection bias, when investigating the association between education level and cardiovascular risk factors. Data from the INTERGENE research programme including 3,610 randomly selected individuals aged 25-74 (1,908 women and 1,702 men), in West Sweden were used. Only 42% of the invited population participated. Non-attendance analyses were done by comparing data from official registries (Statistics Sweden) covering the entire invited study population. This analysis revealed that participants were more likely to be women, have university education, high income, be married and of Nordic origin compared to non-participants. Among participants, all health behaviours studied were significantly related to education. Physical activity, alcohol use and breakfast consumption were higher in the more educated group, while there were more smokers in the less educated group. Central obesity, obesity and hypertension were also significantly associated with lower education level. Weaker associations were observed for blood lipids, diabetes, high plasma glucose level and perceived stress. The socio-demographic differences between participants and non-participants indicated by the register analysis imply potential biases in epidemiological research. For instance, the positive association between education level and frequent alcohol consumption, may, in part be explained by participation bias. For other risk factors studied, an underestimation of the importance of low socioeconomic status may be more likely.

To assess, to control, to exclude: effects of biobehavioral factors on circulating inflammatory markers

Behavioral scientists have increasingly included inflammatory biology as mechanisms in their investigation of psychosocial dynamics on the pathobiology of disease. However, a lack of standardization of inclusion and exclusion criteria and assessment of relevant control variables impacts the interpretation of these studies. The present paper reviews and discusses human biobehavioral factors that can affect the measurement of circulating markers of inflammation. Keywords relevant to inflammatory biology and biobehavioral factors were searched through PubMed. Age, sex, and hormonal status, socioeconomic status, ethnicity and race, body mass index, exercise, diet, caffeine, smoking, alcohol, sleep disruption, antidepressants, aspirin, and medications for cardiovascular disease are all reviewed. A tiered set of recommendations as to whether each variable should be assessed, controlled for, or used as an exclusion criteria is provided. These recommendations provide a framework for observational and intervention studies investigating linkages between psychosocial and behavioral factors and inflammation.

Common risk factors for changes in body weight and psychological well-being in Japanese male middle-aged workers

OBJECTIVES

Overweight and poor psychological well-being are becoming serious health issues in the Japanese workplace. Concurrence of those physical and mental conditions has been pointed out, especially in middle-aged workers. Therefore, we tried to determine common risk factors for body weight gain and the deterioration of psychological well-being in male middle-aged office workers using a five-year follow-up study.

METHODS

We administered General Health Questionnaire-12 (GHQ-12) as an indicator of psychological well-being to 110 male workers with ages ranging from 40-59 years, and analyzed the influence of several psychological factors, namely sense of coherence (SOC), health locus of control (HLC), and lifestyle variables such as exercise frequency, alcohol intake, smoking status, and dietary intake on changes of body mass index and GHQ-12 score.

RESULTS

McNemar's chi-squared test showed significant concurrence of weight gain and deterioration of psychological well-being after five-year follow-up. Low-SOC score, low frequency of exercise, and high-dietary intake at supper were significantly associated with both weight gain and poorer psychological well-being in workers, results which were supported by multiple regression analysis.

CONCLUSIONS

These results suggest that exercise and calorie restriction seem to prevent weight gain and promote psychological well-being in workers. Low SOC, which implies difficulty in coping with stress, may be an important risk factor not only for deterioration of psychological well-being but also for becoming overweight. These assumptions must be confirmed by conducting future intervention studies on SOC and lifestyle including exercise and eating behavior.

Psychosocial Status and Health Related Quality of Life in Relation to the Metabolic Syndrome in a Swedish Middle-Aged Population

Background: The Metabolic Syndrome (MS) is a combination of risk factors related to increased risk of cardiovascular disease. Psychosocial factors and stress have been suggested to be important determinants.

Aim: To analyse how psychosocial factors, perceived stress and health related quality of life are related to MS, and assess if observed associations are dependent of life-style.

Methods: A cross-sectional study of a random sample of 502 men and 505 women aged 45–69, from southeast Sweden, including fasting blood samples, blood pressure, anthropometrics, self-reported data of life-style, psychosocial status and health related quality of life (SF-36). Linear regression models were adjusted for age and, in a second step, also for life-style.

Results: Men and women with MS reported lower levels of physical activity, lower scores on physical and social dimensions of SF-36, and women with MS reported stronger effect of social change compared to those without MS ( p < 0.05), but we found no differences for mental health or perceived stress. The major part of observed associations was lost after adjustment for effects of life-style.

Conclusion: Our data speak against a direct effect of social stress on MS via psychological strain but suggest an indirect pathway via a sedentary life-style.

Abnormal liver function and central obesity associate with work-related fatigue among the Taiwanese workers

AIM: To examine the associations between objective health indicators and high need for recovery (NFR) after work, one of the subjective presentations of work related-fatigue, among apparently healthy workers in modern workplaces.

METHODS: From October to December, 2007, an annual health examination was performed for the workers from an electronics manufacturing factory in Taiwan. Health records of 1216 workers with a relatively homogeneous socioeconomic status were used for analysis. The health checkups included personal and NFR scale questionnaires, physical examinations, blood tests for biochemistry and hematology. The workers within the top tertile NFR score were defined as high-NFR workers.

RESULTS: After adjusted for potential confounders, the workers with elevated alanine aminotransferase (ALT) and central obesity had a significantly higher NFR after work, with increased risks of 1.4-fold [95% confidence interval (CI) = 1.01-2.0] and 1.8-fold (95% CI = 1.2-2.7), respectively. Shiftworkers had a 2.0-fold (95% CI = 1.5-2.6) increased risk for high-NFR. The associations between high-NFR and lipid profiles, blood sugar, hematology indexes or blood pressure were insignificant after controlling for confounders.

CONCLUSION: For apparently healthy workers, high NFR after work is not simply a subjective experience. Objective health measures, such as elevated ALT and increased waist circumference, should be carefully evaluated for the apparently healthy workers having a higher NFR after work.

Self-reported sleep duration is associated with the metabolic syndrome in midlife adults

STUDY OBJECTIVE

Short and long sleep duration have been linked to various risk factors for cardiovascular disease. In the present study, we evaluated the relationship between sleep duration and presence of the metabolic syndrome, which is a cluster of physiologically interrelated risk factors for cardiometabolic disease.

DESIGN/SETTING

Cross-sectional community-based cohort study.

PARTICIPANTS

One thousand two hundred fourteen participants from the Adult Health and Behavior Project registry (aged 30 to 54 years).

MEASUREMENTS

Participants were divided into 4 groups based upon their reported sleep duration. The metabolic syndrome was defined according to the American Heart Association/National Heart Lung and Blood Institute's criteria. Logistic regression was used to test the hypothesis that sleep duration is a significant correlate of the metabolic syndrome and its components.

RESULTS

The observed metabolic syndrome rate (22%) was similar to that of published health statistics for American adults. After covariate adjustment, the odds for having the metabolic syndrome increased by more than 45% in both short and long sleepers, compared with those sleeping 7 to 8 hours per night. Sleep duration was also associated individually with abdominal obesity, elevated fasting glucose, and hypertriglyceridemia. After further adjustment for use of antihypertensive medication, prevalence of the metabolic syndrome and its components remained elevated in short sleepers only.

CONCLUSION

These data suggest that sleep duration is a significant correlate of the metabolic syndrome. Additional studies are needed to evaluate temporal relationships among these measures, the behavioral and physiologic mechanisms that link the two, and their impact on subsequent cardiometabolic disease.

Physical activity as a potential mechanism through which social support may reduce cardiovascular disease risk

Social support has been associated with a reduced risk of cardiovascular disease (CVD). It has been suggested that the protective effect of social support is mediated through the autonomic nervous system and/or unhealthy lifestyle behaviors, but data are sparse, especially in diverse populations. The purpose of this study was to evaluate possible pathways through which social support may reduce cardiovascular disease risk. Baseline data from The National Heart, Lung, and Blood Institute Family Intervention Trial for Heart Health were included in this analysis (N = 501, mean age 48 +/- 13 years, 66% female, 36% nonwhite). Social support was calculated using the Enhancing Recovery in Coronary Heart Disease Patients Social Support Instrument, a validated tool measuring emotional and instrumental support. Emotional support is defined as the belief that one is cared about (high = score > or = 18); instrumental social support is defined as help with services (high = score > or = 3). Demographics, physical activity, and diet were assessed by standardized questionnaires, and cardiovascular disease risk factors were measured systematically. Linear regression models were adjusted for age, race/ethnicity, sex, marital status, and education. Higher instrumental social support was positively associated with minutes of physical activity per week (P = .007). Higher emotional social support was positively associated with number of days of physical activity per week (P = .023), number of servings of wine per week (P = .007), and increased high-density lipoprotein cholesterol (P = .014). A mediational analysis was performed, and the relationship between emotional social support and high-density lipoprotein cholesterol was significantly attenuated by physical activity days per week and number of servings of wine per week. No significant associations were found for other potential mediators tested including body mass index, waist circumference, and intake of omega-3 fatty acids, beer, or liquor. In this ethnically diverse population, emotional social support was linked to higher high-density lipoprotein cholesterol levels through increased physical activity and wine intake, suggesting possible mechanisms through which social support may reduce cardiovascular disease risk.