Predictors of C-reactive protein in the national social life, health, and aging project

Association between oxidative balance score and inflammatory markers in middle-aged and older Japanese people

PURPOSE

This study aimed to investigate the association between oxidative balance score (OBS), wherein higher OBSs indicate lower oxidative stress, and high-sensitivity C-reactive protein (hs-CRP), as well as inflammatory scores, in a large cohort of Japanese adults.

METHODS

In total, 9703 individuals aged 40-69 years participated in a baseline survey of a population-based cohort study in Saga, Japan (2005-2007). OBSs were calculated from 11 prooxidant and antioxidant lifestyle factors, including dietary intake, physical activity, alcohol consumption, and smoking status. Lifestyle data, including dietary intake, were obtained using a self-administered questionnaire. Adjusted geometric means of serum hs-CRP levels were calculated based on OBS quartiles, and linear trend tests were performed, with adjustments for potential confounders. In addition, an inflammatory cytokine z-score was constructed and assessed alongside individual markers.

RESULTS

After adjusting for multiple confounders in both sexes, the results showed a significant inverse association between OBS and serum hs-CRP levels in both men and women. These results remained unaltered when the OBS evaluation excluded powerful prooxidants, serum ferritin, or smoking. There was also an association between OBS and lower inflammatory z-score, indicating reduced overall systemic inflammation.

CONCLUSIONS

These findings suggest that a higher OBS, indicating a greater predominance of antioxidants over prooxidant exposure, is associated with lower hs-CRP levels and reduced systemic inflammation, regardless of sex.

Racial/Ethnic differences in inflammation levels among older adults 56+: an examination of sociodemographic differences across inflammation measure

OBJECTIVE

Chronic inflammation is a key biological risk factor for many widespread adult health conditions. This study examines racial/ethnic differences in inflammation across several inflammatory markers, including selected cytokines that are identified as important for aging and age-related health outcomes.

METHODS

Data came from the 2016 Venous Blood Collection Subsample of the Health and Retirement Study. Using logistic regression models, we compared high-risk categories of C-reactive protein and cytokine markers (IL-6, IL-10, IL-1RA, TNFR1, and TGF-Beta), across race/ethnicity and whether these differences persisted among men and women.

RESULTS

The findings provided evidence of significant race/ethnic differences in inflammatory measures, but the patterns differed across marker types.

CONCLUSIONS

These findings emphasize that race/ethnic differences are not consistently captured across markers of inflammation and that researchers should proceed with caution when using individual markers of inflammation in an effort to not overlook potential racial/ethnic differences in biological risk.

The association between socioeconomic status and C-reactive protein in Bayesian perspective

•This study analyzed the total health inequality on risks of chronic inflammation.•We used Bayesian multiple and distributional regression models.•Between-group posterior distributions show a robust educational gradient in health.•Within-group posterior distributions show polarized risks for individuals.

The Association Between Loneliness and Inflammation: Findings From an Older Adult Sample

Loneliness has been linked to poor mental and physical health outcomes. Past research suggests that inflammation is a potential pathway linking loneliness and health, but little is known about how loneliness assessed in daily life links with inflammation, or about linkages between loneliness and inflammation among older adults specifically. As part of a larger investigation, we examined the cross-sectional associations between loneliness and a panel of both basal and LPS-stimulated inflammatory markers. Participants were 222 socioeconomically and racially diverse older adults (aged 70-90 years; 38% Black; 13% Hispanic) systematically recruited from the Bronx, NY. Loneliness was measured in two ways, with a retrospective trait measure (the UCLA Three Item Loneliness Scale) and an aggregated momentary measure assessed via ecological momentary assessment (EMA) across 14 days. Inflammatory markers included both basal levels of C-reactive protein (CRP) and cytokines (IL-1β, IL-4, IL-6, IL-8, IL-10, TNF-α) and LPS-stimulated levels of the same cytokines. Multiple regression analyses controlled for age, body-mass index, race, and depressive symptoms. Moderation by gender and race were also explored. Both higher trait loneliness and aggregated momentary measures of loneliness were associated with higher levels of CRP (β = 0.16, p = 0.02; β = 0.15, p = 0.03, respectively). There were no significant associations between loneliness and basal or stimulated cytokines and neither gender nor race were significant moderators. Results extend prior research linking loneliness with systemic inflammation in several ways, including by examining this connection among a sample of older adults and using a measure of aggregated momentary loneliness.

Body mass and the epidemic of chronic inflammation in early mid-adulthood

OBJECTIVES

Chronic inflammation is a potentially important mechanism through which social inequalities may contribute to health inequalities over the life course. Excess body fat contributes to chronic inflammation, and younger adults in the US have come of age during a pronounced secular increase in body mass index (BMI). We aim to document levels of chronic inflammation in a nationally representative sample of 33-to-44 year-old adults in the US, and to describe associations with BMI, race/ethnicity, and education.

METHODS

High sensitivity C-reactive protein (CRP) was measured in Wave V (2016-18) of the National Longitudinal Study of Adolescent to Adult Health, with complete data available for 4349 participants. Sex-stratified weighted regression models were implemented to investigate CRP in association with education, race/ethnicity, and BMI.

RESULTS

Geometric mean CRP was 1.9 mg/L, and 35.4% of the sample had CRP >3 mg/L. Females had significantly higher CRP than males. Body mass index was a strong positive predictor of CRP, and education level was negatively associated with CRP. Associations between education and CRP were substantially attenuated after adjusting for BMI. High risk CRP increased linearly with BMI even among the obese: 87.0 percent of females and 74.1 percent of males with class 3 obesity (BMI ≥40) were predicted to have high risk CRP > 3 mg/L.

CONCLUSIONS

The obesity epidemic is producing an epidemic of chronic inflammation in early mid-adulthood in the US. Strong associations between BMI and chronic inflammation portend high risk for future disease-and inequitable distribution of disease-as the cohort ages.

Examining the etiology of early-onset breast cancer in the Canadian Partnership for Tomorrow's Health (CanPath)

PURPOSE

Breast cancer incidence among younger women (under age 50) has increased over the past 25 years, yet little is known about the etiology among this age group. The objective of this study was to investigate relationships between modifiable and non-modifiable risk factors and early-onset breast cancer among three prospective Canadian cohorts.

METHODS

A matched case-control study was conducted using data from Alberta's Tomorrow Project, BC Generations Project, and the Ontario Health Study. Participants diagnosed with breast cancer before age 50 were identified through provincial registries and matched to three control participants of similar age and follow-up. Conditional logistic regression was used to examine the association between factors and risk of early-onset breast cancer.

RESULTS

In total, 609 cases and 1,827 controls were included. A body mass index ≥ 30 kg/m² was associated with a lower risk of early-onset breast cancer (OR 0.65; 95% CI 0.47-0.90), while a waist circumference ≥ 88 cm was associated with an increased risk (OR 1.58; 95% CI 1.18-2.11). A reduced risk was found for women with ≥ 2 pregnancies (OR 0.76; 95% CI 0.59-0.99) and a first-degree family history of breast cancer was associated with an increased risk (OR 1.95; 95% CI 1.47-2.57).

CONCLUSIONS

In this study, measures of adiposity, pregnancy history, and familial history of breast cancer are important risk factors for early-onset breast cancer. Evidence was insufficient to conclude if smoking, alcohol intake, fruit and vegetable consumption, and physical activity are meaningful risk factors. The results of this study could inform targeted primary and secondary prevention for early-onset breast cancer.

Gender Minority Stress, Support, and Inflammation in Transgender and Gender-Nonconforming Youth

Purpose: Transgender and gender-nonconforming (TGNC) youth often report higher rates of chronic social stressors such as victimization, discrimination, and rejection. Some of these gender-based stressors may have long-range physical health consequences through inflammation pathways. This study evaluates the feasibility and acceptability of adding biological measures of inflammation to an ongoing prospective clinical study of TGNC youth (ages 9-20 years), initiating affirming medical therapy at a large, urban children's hospital (N=56). We also examine the relationship between gender-based sources of stress and support with inflammation. This is the first study to explore how gender identity, social stressors, and social supports may contribute to poorer health in TGNC youth through inflammation and immune dysregulation pathways. Methods: Between October 2016 and August 2018, the study team collected dried blood spot (DBS) samples and health measures during clinical visits. Participants also completed computer-assisted surveys assessing gender minority stress and support during these visits. We used regression analysis to evaluate differences in C-reactive protein (CRP) controlling for demographics, health, gender-based stress, and supports. Results: The results from this study indicate that adding DBS samples to assess inflammation was feasible and acceptable in a clinical sample of TGNC youth seeking affirming-medical interventions. We found an association between greater inflammation and the composite score for greater gender-based stressors and lower gender-based supports using the Gender Minority Stress and Resilience Tool (GMSR); however, we did not find statistically significant differences in CRP associated with any of the individual GMSR subscales assessing various types of gender-based supports or stressors. Conclusion: More research is necessary to evaluate how different sources of gender-based support and stress relate to inflammation with larger sample sizes.

Early origins of socioeconomic inequalities in chronic inflammation: Evaluating the contributions of low birth weight and short breastfeeding

The United States is characterized by persistent and widening social inequities in a wide range of adult health outcomes. A life course approach challenges us to consider if, and how, these inequities trace back to early life conditions, and chronic inflammation represents a potentially important mechanism through which early environments may have lasting effects on health in adulthood. Low birth weight (LBW) and shorter durations of breastfeeding both predict increased inflammation in adulthood, which is associated with increased risk for cardiovascular disease, metabolic syndrome, and all-cause mortality. Using data from a large representative sample of young adults in the US (National Longitudinal Study of Adolescent to Adult Health (Add Health)), we document the socioeconomic status (SES) gradient in chronic inflammation, as indicated by concentrations of C-reactive protein (CRP). Using a nested set of structural equation models and marginal standardization techniques, we investigate the extent to which this gradient is explained by patterns of LBW and breastfeeding in infancy. Findings reveal a particularly important role for breastfeeding duration: Based on model predictive margins, increasing breastfeeding duration to three or more months corresponds to a flattening of the SES gradient by 80%, and 83% when LBW is eliminated. This study expands current understandings of the consequential role of developmental environments for population health and for addressing health inequities in future generations.

IL-1Rahigh-IL-4low-IL-13low: A Novel Plasma Cytokine Signature Associated with Olfactory Dysfunction in Older US Adults

Inflammation has been implicated in physical frailty, but its role in sensory impairment is unclear. Given that olfactory impairment predicts dementia and mortality, determining the role of the immune system in olfactory dysfunction would provide insights mechanisms of neurosensory decline. We analyzed data from the National Social Life, Health and Aging Project, a representative sample of home-dwelling older US adults. Plasma levels of 18 cytokines were measured using standard protocols (Luminex xMAP). Olfactory function was assessed with validated tools (n-butanol sensitivity and odor identification, each via Sniffin' Sticks). We tested the association between cytokine profiles and olfactory function using multivariate ordinal logistic regression, adjusting for age, gender, race/ethnicity, education level, cognitive function, smoking status, and comorbidity. Older adults with the IL-1Rahigh-IL-4low-IL-13low cytokine profile had worse n-butanol odor sensitivity (odds ratio [OR] = 1.61, 95% confidence interval [CI] 1.19-2.17) and worse odor identification (OR = 1.42, 95% CI 1.11-1.80). Proinflammatory, Th1, or Th2 cytokine profiles were not associated with olfactory function. Moreover, accounting for physical frailty did not alter the main findings. In conclusion, we identified a plasma cytokine signature-IL-1Rahigh-IL-4low-IL-13low-that is associated with olfactory dysfunction in older US adults. These data implicate systemic inflammation in age-related olfactory dysfunction and support a role for immune mechanisms in this process, a concept that warrants additional scrutiny.

Positive and negative aspects of social relations and low-grade inflammation in Copenhagen Aging and Midlife Biobank

The association between social relations and health outcomes is well described, but pathways are relatively poorly understood. Inflammation has been suggested as a potential physiological pathway, linking social relations to adverse health outcomes. However, previous studies have shown ambiguous results and have for the vast majority been based on studies small in sample size. The aim of the present study is to examine the association between comprehensive measures of structural and positive as well as negative functional aspects of social relations, across four relational domains-partner/spouse, children, other family and friends, and the level of systemic low-grade inflammation in a large population-based middle-aged cohort and to examine variation by gender and socioeconomic position in these associations. The study comprised of 5576 participants in the Copenhagen Aging and Midlife Biobank. The inflammatory biomarkers collected in late midlife included C-reactive protein, Interleukin-6, and TNF-alpha. Multiple linear regression models were implemented to explore associations between social relations and inflammatory measures controlling for gender, age, socioeconomic position, marital status, early major lifeevents and morbidity. Results show weak and ambiguous associations in all analyses. There were no strong indications of interaction with socioeconomic position. Concluding cautiously, men appear to be more vulnerable toward living alone and low contact frequency with family compared to women as regards high level of low-grade inflammation. In conclusion, this large-scale population-based study among middle-aged men and women showed no association between social relations and low-grade inflammation.

Socioeconomic Status and Biological Risks for Health and Illness Across the Life Course

OBJECTIVES

We assess the temporal properties and biosocial mechanisms underlying the associations between early-life socioeconomic status (SES) and later health. Using a life-course design spanning adolescence to older adulthood, we assess how early life and various dimensions of adult SES are associated with immune and metabolic function in different life stages and examine possible bio-behavioral and psychosocial mechanisms underlying these associations.

METHOD

Data for this study come from 3 national studies that collectively cover multiple stages of the life course (Add Health, MIDUS, and HRS). We estimated generalized linear models to examine the prospective associations between early-life SES, adult SES, and biomarkers of chronic inflammation and metabolic disorder assessed at follow-up. We further conducted formal tests of mediation to assess the role of adult SES in linking early SES to biological functions.

RESULTS

We found that early-life SES exerted consistent protective effects for metabolic disorder across the life span, but waned with time for CRP. The protective effect of respondent education remained persistent for CRP but declined with age for metabolic disorder. Adult income and assets primarily protected respondents against physiological dysregulation in middle and old ages, but not in early adulthood.

DISCUSSION

These findings are the first to elucidate the life-course patterns of SES that matter for underlying physiological functioning during the aging process to produce social gradients in health.

Associations of serum CRP levels with demographics, health behaviors, and risk of cancer among the Mexican American Mano A Mano Cohort

C-Reactive protein (CRP) is a well-known inflammatory marker, and elevated CRP levels has been reported to be associated with the risk of various cancers. To date, no study has investigated the association between elevated CRP and incidents of cancer among Mexican Americans. In the current prospective cohort study, we measured pre-diagnostic CRP levels in serum samples and evaluated their relationships with demographic characteristics and health behaviors associated with cancer risk among 2753 Mexican Americans selected from the Mano-A-Mano Mexican American Cohort Study. At baseline, median levels of serum CRP significantly differed by demographics (sex, age category, marital status, and education levels) and health behaviors (cigarette smoking status, alcohol drinking status, BMI category, and physical activity levels). In the multivariable analysis, the study participants who were women, older, never drinking alcohol, overweight or obese, and physically inactive had increased likelihood of having high CRP levels (≥ median levels among all study participants) compared to their counterparts. A total of 177 cancer cases were identified during the follow-up with a median follow-up time of 127 months. In the quartile analysis, study participants in the 4^th quartile with highest CRP levels had significantly 1.88 fold increased risk of cancer (hazard ratio (HR) = 1.88, 95%CI: 1.12, 3.13) compared to those in the 1^st quartile with lowest CRP levels. The association was further confirmed in analyses using clinical CRP levels. In summary, our findings suggested that serum CRP levels have potential to serve as a predictive marker of cancer risk in Mexican Americans.

Genome-wide analysis of DNA methylation in relation to socioeconomic status during development and early adulthood

OBJECTIVES

Socioeconomic status (SES) is a powerful determinant of health, but the underlying biological mechanisms are poorly understood. This study investigates whether levels of DNA methylation at CpG sites across the genome are associated with SES in a cohort of young adults in the Philippines.

METHODS

DNA methylation was assayed with the Illumina HumanMethylation450 Bead Chip, in leukocytes from 489 participants in the Cebu Longitudinal Health and Nutrition Survey (mean age = 20.9 years). SES was measured in infancy/childhood and adulthood, and was based on composite measures of income, assets, and education. Genome-wide analysis of variable probes identified CpG sites significantly associated with SES after adjustment for multiple comparisons. Functional enrichment analysis was used to identify biological pathways associated with these sites.

RESULTS

A total of 2,546 CpG sites, across 1,537 annotated genes, were differentially methylated in association with SES. In comparison with high SES, low SES was associated with increased methylation at 1,777 sites, and decreased methylation at 769 sites. Functional enrichment analysis identified over-representation of biological pathways related to immune function, skeletal development, and development of the nervous system.

CONCLUSIONS

Socioeconomic status predicts DNA methylation at a large number of CpG sites across the genome. The scope of these associations is commensurate with the wide range of biological systems and health outcomes that are shaped by SES, and these findings suggest that DNA methylation may play an important role.

Inflammation and quality of life in later life: findings from the health, well-being and aging study (SABE)

BACKGROUND

Few studies have specifically investigated the inverse relationship between reduced quality of life in different domains and elevated C-reactive protein (CRP) serum levels in older adults. Therefore, this study investigates the cross-sectional association between quality of life and inflammation in older Brazilian adults.

METHODS

Data were collected from 1255 participants from the third wave (2010) of the Brazilian Health, Well-being and Aging study (SABE), a community-based cohort study of aging. Inflammation was assessed using CRP serum levels and quality of life (QoL) was measured using the 12-item Short-Form Health Survey (SF-12) questionnaire. The covariates included age, sex, education level, financial sufficiency, number of non-communicable diseases, self-reported doctor diagnosed diseases, Activity of Daily Living (ADL) difficulties, Body Mass Index (BMI), and waist circumference.

RESULTS

The fully adjusted models showed that older adults with low scores in the physical domain of the SF12 (OR 1.34, 95%CI 1.02;1.77) and high BMI values (> 30) (OR 2.05, 95%CI 1.50;2.81) were more likely to present high CRP serum levels.

CONCLUSION

Our findings suggest a significant association of lower scores in the physical domain of quality of life and the presence of obesity with high CRP serum levels.

Concurrent Social Disadvantages and Chronic Inflammation: The Intersection of Race and Ethnicity, Gender, and Socioeconomic Status

Disadvantaged social statuses, such as being female, poor, or a minority, are associated with increased psychosocial stress and elevated circulating concentrations of C-reactive protein, a biomarker of chronic inflammation and indicator of cardiovascular health. Individuals' experience of embodying psychosocial stress revolves around the multiplicative effects of concurrent gender, socioeconomic, and racial and ethnic identities. This study expands on prior research by examining chronic inflammation at the intersection of race and ethnicity, gender, socioeconomic status, and age group to understand which demographic subgroups in society are most vulnerable to the cumulative effects of social disadvantage. Using data from the National Health and Nutrition Examination Survey 2007-2010, the findings reveal inflammation disparities between non-poor whites and the following demographic subgroups, net of sociodemographic and biological factors: young poor Hispanic women, young poor white men, young poor and non-poor Hispanic men, middle-aged poor and non-poor black women, middle-aged poor and non-poor black men, and middle-aged poor Hispanic men. Disparities in inflammation on account of social disadvantage are most evident among those aged 45-64 years and diminish for those 65 and older in both men and women.

Unemployment and inflammatory markers in England, Wales and Scotland, 1998-2012: Meta-analysis of results from 12 studies

INTRODUCTION

Unemployment represents for many affected individuals a substantial source of psychosocial stress, and is linked to both increased risk of morbidity and mortality and adverse health-related behaviours. Few studies have examined the association of unemployment with systemic inflammation, a plausible mediator of the associations of psychosocial stress and health, and results are mixed and context dependent. This study examines the association of unemployment with C-reactive protein (CRP) and fibrinogen, two markers of systemic inflammation.

METHODS

A random-effects meta-analysis was performed using a multilevel modelling approach, including 12 national UK surveys of working-age participants in which CRP and fibrinogen were measured between 1998 and 2012 (N=30,037 economically active participants). The moderating impact of participant age and UK country was explored.

RESULTS

CRP and fibrinogen were elevated in unemployed compared to employed participants; jobseekers were also more likely (Odds Ratio: 1.39, p<0.001) to have CRP levels corresponding to high cardiovascular risk (>3mg/L), after adjustment for age, gender, education, long-term illness, smoking, and body mass index. Associations were not explained by mental health. Associations peaked in middle-age, and were stronger in Scotland and Wales than in England.

CONCLUSIONS

Our study demonstrates that systemic inflammation is associated with an important but little-studied aspect of the social environment, as it is elevated in unemployed compared to employed survey participants. Modifications suggest the association of unemployment and inflammation is substantially influenced by contextual factors, and may be especially strong in Wales, where further investigation of this relationship is needed.

Early-Life Socioeconomic Status and Adult Physiological Functioning: A Life Course Examination of Biosocial Mechanisms

A growing literature has demonstrated a link between early-life socioeconomic conditions and adult health at a singular point in life. No research exists, however, that specifies the life course patterns of socioeconomic status (SES) in relation to the underlying biological processes that determine health. Using an innovative life course research design consisting of four nationally representative longitudinal datasets that collectively cover the human life span from early adolescence to old age (Add Health, MIDUS, NSHAP, and HRS), we address this scientific gap and assess how SES pathways from childhood into adulthood are associated with biophysiological outcomes in different adult life stages. For each dataset, we constructed standardized composite measures of early-life SES and adult SES and harmonized biophysiological measurements of immune and metabolic functioning. We found that the relative importance of early-life SES and adult SES varied across young, mid, and late adulthood, such that early-life SES sets a life course trajectory of socioeconomic well-being and operates through adult SES to influence health as adults age. We also documented evidence of the detrimental health effects of downward mobility and persistent socioeconomic disadvantage. These findings are the first to specify the life course patterns of SES that matter for underlying biophysiological functioning in different stages of adulthood. The study thus contributes new knowledge critical for improving population health by identifying the particular points in the life course at which interventions might be most effective in preventing disease and premature mortality.

Does Inflammation Mediate Relationships Between Racial Identity and Onset of Menopause Among US Adults?

We assess how well differences in ethnoracial background may predict timing of menopause among females in the USA and whether or not inflammatory biomarker levels appear to mediate these overall associations. We use data from the National Social Life, Health, and Aging Project (NSHAP) to model apparent net effects from race on menopausal onset, as well as possible mediating influences from the inflammatory biomarker C-reactive protein (CRP). Using continuous time event history analysis, we assess and frame overall relationships between race and menopausal age. We use structural equation modeling to assess potential mediating effects from CRP and to estimate direct and indirect components of these apparent effects. Our findings suggest that on average, black females experience menopause earlier than their peers of other racial backgrounds, and have higher inflammatory biomarker levels. Both black race and higher CRP have negative and significant direct associations with menopausal age. CRP appears to partially mediate the overall association between black race and earlier menopause. This apparent mediation persists with statistical controls for income, education, and body mass index. Our study concludes with recommendations for future research on racial identity, inflammation, and menopausal onset. We focus our recommendations on intersectional forms of inequality that may affect black females in later life.

Weight Gain Trajectories Associated With Elevated C-Reactive Protein Levels in Chinese Adults

BACKGROUND

Recent longitudinal work suggests that weight change is an important risk factor for inflammation across the full range of BMI. However, few studies have examined whether the risk of inflammation differs by patterns of weight gain over time. Using latent class trajectory analysis, we test whether patterns of weight gain are associated with elevated high-sensitivity C-reactive protein (hs-CRP 2-10 mg/L).

METHODS AND RESULTS

Data come from China Health and Nutrition Survey (CHNS) participants (n=5536), aged 18 at baseline to 66 years in 2009, with measured weight over 18 years. Latent class trajectory analysis was used to identify weight-change trajectories in 6 age and sex strata. Multivariable general linear mixed-effects models fit with a logit link were used to assess the risk of elevated hs-CRP across weight trajectory classes. Models were fit within age and sex strata, controlling for baseline weight, adult height, and smoking, and included random intercepts to account for community-level correlation. Steeper weight-gain trajectories were associated with greater risk of elevated hs-CRP compared to more moderate weight-gain trajectories in men and women. Initially high weight gain followed by weight loss was associated with lower risk of elevated hs-CRP in women aged 18 to 40.

CONCLUSIONS

Latent class trajectory analysis identified heterogeneity in adult weight change associated with differential risk of inflammation independently of baseline weight and smoking. These results suggest that trajectories of weight gain are an important clinical concern and may identify those at risk for inflammation and the development of cardiometabolic disease.

All in the family: The link between kin network bridging and cardiovascular risk among older adults

While considerable work has examined the association between social relationships and health, most of this research focuses on the relevance of social network composition and the quality of dyadic ties. In this study, I consider how the social network structure of ties among older adults' close family members may affect cardiovascular health in later life. Using data from 938 older adults that participated in Waves 1 and 2 of the National Social Life, Health, and Aging Project (NSHAP), I test whether older adults who occupy bridging positions among otherwise disconnected or poorly connected kin in their personal social network are more likely to present elevated levels of C-reactive protein (CRP), a biomarker for cardiovascular risk. Results indicate that occupying a bridging position among family members is significantly associated with elevated CRP. This effect is unique to bridging kin network members. These findings suggest that ties among one's closest kin may generate important resources and norms that influence older adults' health, such that bridging kin network members may compromise physical wellbeing. I discuss these results in the context of prior work on social support, family solidarity, and health in later life.

Association of modeled long-term personal exposure to ultrafine particles with inflammatory and coagulation biomarkers

BACKGROUND

Long-term exposure to fine particulate matter has been linked to cardiovascular disease and systemic inflammatory responses; however, evidence is limited regarding the effects of long-term exposure to ultrafine particulate matter (UFP, <100nm). We used a cross-sectional study design to examine the association of long-term exposure to near-highway UFP with measures of systemic inflammation and coagulation.

METHODS

We analyzed blood samples from 408 individuals aged 40-91years living in three near-highway and three urban background areas in and near Boston, Massachusetts. We conducted mobile monitoring of particle number concentration (PNC) in each area, and used the data to develop and validate highly resolved spatiotemporal (hourly, 20m) PNC regression models. These models were linked with participant time-activity data to determine individual time-activity adjusted (TAA) annual average PNC exposures. Multivariable regression modeling and stratification were used to assess the association between TAA-PNC and single peripheral blood measures of high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), tumor-necrosis factor alpha receptor II (TNFRII) and fibrinogen.

RESULTS

After adjusting for age, sex, education, body mass index, smoking and race/ethnicity, an interquartile-range (10,000particles/cm(3)) increase in TAA-PNC had a positive non-significant association with a 14.0% (95% CI: -4.6%, 36.2%) positive difference in hsCRP, an 8.9% (95% CI: -0.4%, 10.9%) positive difference in IL-6, and a 5.1% (95% CI: -0.4%, 10.9%) positive difference in TNFRII. Stratification by race/ethnicity revealed that TAA-PNC had larger effect estimates for all three inflammatory markers and was significantly associated with hsCRP and TNFRII in white non-Hispanic, but not East Asian participants. Fibrinogen had a negative non-significant association with TAA-PNC.

CONCLUSIONS

Our findings suggest an association between annual average near-highway TAA-PNC and subclinical inflammatory markers of CVD risk.

Exploring Black-White Differences in the Relationship Between Inflammation and Timing of Menopause

Understanding the biosocial context of menopausal timing offers insight into social and health inequalities. Prior research on inflammatory chronic conditions suggests that inflammation may predict how early women experience menopause. We explore the ability of black race to moderate the overall relationship between chronic inflammation and timing of menopause. We use data from the National Social Life, Health, and Aging Project on inflammation, age of last menstruation, and race as well as relevant social and medical covariates. We conduct event history modeling to predict age at menopause by inflammatory biomarker levels. Using interaction analysis, we investigate whether being black may shape the overall relationship between inflammation status and menopause timing. Our analyses find no significant statistical interactions between black race and inflammation in predicting menopausal onset. However, we do identify independent correlational relationships between inflammation and black race (r = 0.136) and between menopausal timing and black race (r = -0.129) as well as inflammation (r = -0.138) that emerge as significant in corresponding regression models. We conclude that race probably does not moderate associations between inflammation and menopause. Yet, we also note that the original parameter estimate for black race's impact on menopausal onset (HR = 1.29, p < 0.05) becomes non-significant in a model that includes inflammation (HR = 1.06, p < 0.01). To translate our findings into policy and practice implications, we present alternate conceptualizations of black-white disparity in the inflammation-menopause relationship and recommend future research using mediation modeling.

Empirical redefinition of comprehensive health and well-being in the older adults of the United States

The World Health Organization (WHO) defines health as a "state of complete physical, mental and social well-being and not merely the absence of disease or infirmity." Despite general acceptance of this comprehensive definition, there has been little rigorous scientific attempt to use it to measure and assess population health. Instead, the dominant model of health is a disease-centered Medical Model (MM), which actively ignores many relevant domains. In contrast to the MM, we approach this issue through a Comprehensive Model (CM) of health consistent with the WHO definition, giving statistically equal consideration to multiple health domains, including medical, physical, psychological, functional, and sensory measures. We apply a data-driven latent class analysis (LCA) to model 54 specific health variables from the National Social Life, Health, and Aging Project (NSHAP), a nationally representative sample of US community-dwelling older adults. We first apply the LCA to the MM, identifying five health classes differentiated primarily by having diabetes and hypertension. The CM identifies a broader range of six health classes, including two "emergent" classes completely obscured by the MM. We find that specific medical diagnoses (cancer and hypertension) and health behaviors (smoking) are far less important than mental health (loneliness), sensory function (hearing), mobility, and bone fractures in defining vulnerable health classes. Although the MM places two-thirds of the US population into "robust health" classes, the CM reveals that one-half belong to less healthy classes, independently associated with higher mortality. This reconceptualization has important implications for medical care delivery, preventive health practices, and resource allocation.

Basal neutrophil function in human aging: Implications in endothelial cell adhesion

Much attention has been drawn to the pro-inflammatory condition that accompanies aging. This study compared parameters from non-stimulated neutrophils, obtained from young (18-30 years old [y.o.]) and elderly (65-80 y.o.) human volunteers. Measured as an inflammatory marker, plasmatic concentration of hs-CRP was found higher in elderly individuals. Non-stimulated neutrophil production of ROS and NO was, respectively, 38 and 29% higher for the aged group. From the adhesion molecules evaluated, only CD11b expression was elevated in neutrophils from the aged group, whereas no differences were found for CD11a, CD18, or CD62. A 69% higher non-stimulated in vitro neutrophil/endothelial cell adhesion was observed for neutrophils isolated from elderly donors. Our results suggest that with aging, neutrophils may be constitutively producing more reactive species in closer proximity to endothelial cells of vessel walls, which may both contribute to vascular damage and reflect a neutrophil intracellular disrupted redox balance, altering neutrophil function in aging.

Does disorder get "into the head" and "under the skin"? Layered contexts and bi-directional associations

This paper utilizes a layered context approach to examine how neighborhood and household conditions are associated with the objective and subjective well-being of older adults. Using two waves of data from the National Social Life, Health, and Aging Project (n=2261), we assess subjective mental health through self-reported measures of perceived stress and distress and objective physical health through C-reactive protein (CRP). Environmental disorder was measured by independent, trained interviewers. Cross-sectional results indicate that household disorder is positively associated with perceived stress and distress, overwhelming the association between neighborhood disorder and mental health outcomes. Yet longitudinal findings point to a reverse process, whereby highly stressed women experience deterioration in their home environment across the two waves. Few significant findings surfaced for CRP. Taken together, our findings illustrate the complex interplay between health and proximal environments and underscore how feedback cycles operate between "health" and "place" across multiple outcomes.

Mediation analysis of relationships between chronic inflammation and quality of life in older adults

Background

This article summarizes exploratory analyses of relationships between chronic inflammation, its physical consequences, and quality of life (QoL). It summarizes key findings from preliminary analyses, and contextualizes these results with extant sociomedical literature to recommend directions for future research.

Methods

Cross-sectional data from the National Social Life, Health, and Aging Project (NSHAP) were used to explore these relationships. Inflammation was assessed via the biomarker C-reactive protein (CRP). We examined associations between CRP levels and two different domains of QoL: happiness with life in general and happiness with intimate relationships. We used ordinal logistic regression with companion OLS models and Sobel-Goodman tests to assess potential mediation, and also conducted a variety of sensitivity analyses.

Results

Findings suggest that mediation pathways for the overall association between chronic inflammation and QoL may differ markedly across particular outcome constructs. Specifically, it shows mediation potential for the clinical sequelae of chronic inflammation in frameworks using happiness as an outcome measure, but not in those using relationship satisfaction. Disability appears to mediate the effect of inflammation by 27 %; chronic pain appears to exert a similar mediation effect of 21 %.

Conclusions

Pain and disability linked to chronic inflammation appear to play a small but significant mediating role in the overall reduction in QoL observed among older adults with biomarker evidence of chronic inflammation. We note that these patterns are best framed as dynamic elements of a complex causal fabric, rather than powerful determinants that override other factors contributing to QoL. Hypotheses for further exploration using longitudinal data from the NSHAP are thus offered, pending availability of Wave III data in future years.

The physiological impacts of wealth shocks in late life: Evidence from the Great Recession

Given documented links between individual socioeconomic status (SES) and health, it is likely that-in addition to its impacts on individuals' wallets and bank accounts-the Great Recession also took a toll on individuals' disease and mortality risk. Exploiting a quasi-natural experiment design, this study utilizes nationally representative, longitudinal data from the National Social Life, Health, and Aging Project (NSHAP) (2005-2011) (N = 930) and individual fixed effects models to examine how household-level wealth shocks experienced during the Great Recession relate to changes in biophysiological functioning in older adults. Results indicate that wealth shocks significantly predicted changes in physiological functioning, such that losses in net worth from the pre-to the post-Recession period were associated with increases in systolic blood pressure and C-reactive protein over the six year period. Further, while the association between wealth shocks and changes in blood pressure was unattenuated with the inclusion of other indicators of SES, psychosocial well-being, and health behaviors in analytic models, we document some evidence of mediation in the association between changes in wealth and changes in C-reactive protein, which suggests specificity in the social and biophysiological mechanisms relating wealth shocks and health at older ages. Linking macro-level conditions, meso-level household environments, and micro-level biological processes, this study provides new insights into the mechanisms through which economic inequality contributes to disease and mortality risk in late life.

Psychobiobehavioral Model for Preterm Birth in Pregnant Women in Low- and Middle-Income Countries

Preterm birth (PTB) is a final common outcome resulting from many interrelated etiological pathways; of particular interest is antenatal psychosocial distress (i.e., stress, anxiety, and depression). In LMI countries, both exposure to severe life stressors and rate of PTB are on average greater when compared with high-income countries. In LMI countries women are exposed to some of the most extreme psychosocial stress worldwide (e.g., absolute poverty, limited social resources). High prevalence of antenatal stress and depression have been observed in some studies from LMI countries. We propose a psychosocial, biological, and behavioral model for investigating the complex multisystem interactions in stress responses leading to PTB and explain the basis of this approach. We discuss ethical considerations for a psychosocial, biological, and behavioral screening tool to predict PTB from a LMI country perspective.

Elevated inflammatory biomarkers during unemployment: modification by age and country in the UK

BACKGROUND

There is raised risk of mortality following unemployment, and reviews have consistently found worse psychological health among the unemployed. Inflammation is increasingly implicated as a mediating factor relating stress to physical disease and is strongly linked to depression. Inflammation may, therefore, be implicated in processes associated with excess mortality and morbidity during unemployment. This study examined associations of unemployment with inflammatory markers among working-age men and women from England and Scotland.

METHODS

Cross-sectional analyses using data from the Health Survey for England and the Scottish Health Survey collected between 1998 and 2010. Systemic inflammation was indexed by serum concentrations of C reactive protein (CRP) and fibrinogen, and compared between participants currently employed/self-employed, currently unemployed and other groups.

RESULTS

CRP, fibrinogen and odds of CRP >3 mg/L were all significantly raised for the unemployed, as compared to the employed participants (eg, OR for CRP >3 mg/L=1.43, CI 1.15 to 1.78 N=23 025), following adjustment for age, gender, occupational social class, housing tenure, smoking, alcohol consumption, body mass index, long-term illness and depressive/anxiety symptoms. Strengths of associations varied considerably by both age and country/region, with effects mainly driven by participants aged ≥48 and participants from Scotland, which had comparatively high unemployment during this time.

CONCLUSIONS

Current unemployment is associated with elevated inflammatory markers using data from two large-scale, nationally representative UK studies. Effect modification by age suggests inflammation may be particularly involved in processes leading to ill-health among the older unemployed. Country/regional effects may suggest the relationship of unemployment with inflammation is strongly influenced by contextual factors, and/or reflect life course accumulation processes.

Chronic inflammation and quality of life in older adults: a cross-sectional study using biomarkers to predict emotional and relational outcomes

Background

This study explores relationships between chronic inflammation and quality of life, making a case for biopsychosocial modeling of these associations. It builds on research from social and clinical disciplines connecting chronic conditions, and inflammatory conditions specifically, to reduced quality of life.

Methods

Data from Wave I of the National Social Life, Health, and Aging Project are modeled using ordinal logistic and ordinary least-squares regression techniques. Inflammation is measured using C-reactive protein; quality of life is conceptualized as happiness with life overall as well as intimate relationships specifically.

Results

For most NSHAP participants, chronic inflammation significantly predicts lower odds of reporting high QoL on both emotional and relational measures. Social structural factors do not confound these associations. Inconsistent results for participants with very high (over 6 mg/L) CRP measurements suggest additional social influences.

Conclusions

Findings echo strong theoretical justification for investigating relationships between CRP and QoL in greater detail. Further research should explore possible mediation of these associations by sociomedical sequelae of chronic disease as well as social relationship dynamics. Elaboration is also needed on the mechanisms by which social disadvantage may cause chronic inflammation.

Long-term effects of birth weight and breastfeeding duration on inflammation in early adulthood

Chronic inflammation is a potentially important physiological mechanism linking early life environments and health in adulthood. Elevated concentrations of C-reactive protein (CRP)--a key biomarker of inflammation--predict increased cardiovascular and metabolic disease risk in adulthood, but the developmental factors that shape the regulation of inflammation are not known. We investigated birth weight and breastfeeding duration in infancy as predictors of CRP in young adulthood in a large representative cohort study (n = 6951). Birth weight was significantly associated with CRP in young adulthood, with a negative association for birth weights 2.8 kg and higher. Compared with individuals not breastfed, CRP concentrations were 20.1%, 26.7%, 29.6% and 29.8% lower among individuals breastfed for less than three months, three to six months, 6-12 months and greater than 12 months, respectively. In sibling comparison models, higher birth weight was associated with lower CRP for birth weights above 2.5 kg, and breastfeeding greater than or equal to three months was significantly associated with lower CRP. Efforts to promote breastfeeding and improve birth outcomes may have clinically relevant effects on reducing chronic inflammation and lowering risk for cardiovascular and metabolic diseases in adulthood.

Relationships between biomarkers of inflammation, ovarian steroids, and age at menarche in a rural Polish sample

OBJECTIVES

To test the hypothesis that life history trade-offs between maintenance and reproductive effort would be evident through inverse associations between levels of a biomarker of inflammation [C-reactive protein (CRP)], and ovarian hormones. Associations between CRP and age at menarche were also explored.

METHODS

Urinary CRP, salivary progesterone, and estradiol were measured over one menstrual cycle from rural Polish women (n = 25), representing a natural fertility sample. Age of menarche was assessed through interview recall methods. We used minimum second-order Akaike Information Criteria as a means of multiple regression model selection, and repeated measures ANOVA to test cycle-dependent hypotheses.

RESULTS

Comparisons of individuals in high and low CRP tertiles revealed that those with high CRP had significantly lower progesterone (luteal P = 0.03, mid luteal P = 0.007) but not estradiol (follicular P = 0.21, luteal P = 0.15) concentrations through the menstrual cycle. However, when the age at menarche was included in the analysis, both age at menarche and urinary CRP were negatively associated with estradiol (R(2) = 0.44, P = 0.0007). Age at menarche and estradiol were the strongest negative predictors of CRP (R(2) = 0.52, P = 0.0001).

CONCLUSIONS

Inflammation itself may suppress ovarian function, or indicate immune challenges that lead to ovarian suppression. The timing of menarche may also influence adult inflammatory sensitivity and ovarian hormone concentrations. This lends support to existing models of trade-offs between maintenance and reproduction in women.

Long-term variability of inflammatory markers and associated factors in a population-based cohort

OBJECTIVES

To investigate long-term variability in serum high-sensitivity C-reactive protein (CRP) and interleukin-6 (IL-6) and to determine associated risk factors for high-risk inflammatory profiles.

DESIGN

Prospective population-based cohort study.

PARTICIPANTS

Participants (N = 1,443) of the Epidemiology of Hearing Loss Study and the Beaver Dam Eye Study, two population-based prospective studies of aging in the same cohort.

MEASUREMENTS

In participants aged 43 to 79 at the initial examination (1988-1990), serum high-sensitivity CRP was measured from three time-points (1988-1990, 1998-2000, 2009-2010), and serum IL-6 was measured from two (1998-2000, 2009-2010).

RESULTS

When IL-6 levels were categorized into tertiles, 50.8% of participants were in the same group 10 years later (weighted kappa (κ) = 0.34). When CRP was categorized into three risk groups, 53.4% of participants were in the same group 10 years later (κ = 0.36), and 32.4% were in the same group at all three examinations (κ = 0.27). IL-6 increased from a geometric mean of 1.54 pg/L to 1.78 pg/L over 10 years, whereas CRP increased from a geometric mean of 1.67 mg/L to 2.25 mg/L over 10 years and then decreased to 1.93 mg/L over the next 10 years. These 10-year decreases in CRP were not observed in those not reporting statin use. Factors associated with long-term higher levels of IL-6 and CRP were older age (IL-6), obesity, smoking, lower physical activity (IL-6), lower high-density lipoprotein cholesterol (IL-6), and a history of statin (non)use (CRP).

CONCLUSION

Inflammatory marker levels tracked over the long term into older age with within-person increases were observed. Several potentially modifiable risk factors were associated with long-term higher levels of inflammatory markers.

How does race get "under the skin"?: inflammation, weathering, and metabolic problems in late life

Using nationally representative data from the 2005-2006 U.S. National Social Life, Health, and Aging Project, this study queries the mechanisms underlying worse metabolic outcomes--blood-sugar control and cardiovascular health--among black than white men ages 57-85. Results indicate that contrary to much of the academic literature as well as media accounts-implicitly rooted in a "culture of irresponsibility" model--older black men's social isolation, poor health behaviors, or obesity may not play a major role in their worse metabolic problems. Instead, these outcomes seem to derive more consistently from a factor almost unexamined in the literature--chronic inflammation, arguably a biological "weathering" mechanism induced by these men's cumulative and multi-dimensional stress. These findings highlight the necessity of focusing attention not simply on proximal behavioral interventions, but on broader stress-inducing social inequalities, to reduce men's race disparities in health.

Association between use of specialty dietary supplements and C-reactive protein concentrations

Laboratory evidence suggests that certain specialty dietary supplements have antiinflammatory properties, though evidence in humans remains limited. Data on a nationally representative sample of 9,947 adults from the 1999-2004 cycles of the National Health and Nutrition Examination Survey were used to assess the associations between specialty supplement use and inflammation, as measured by serum high-sensitivity C-reactive protein (hs-CRP) concentration. Using survey-weighted multivariate linear regression, significant reductions in hs-CRP concentrations were associated with regular use of glucosamine (17%, 95% confidence interval (CI): 7, 26), chondroitin (22%, 95% CI: 8, 33), and fish oil (16%, 95% CI: 0.3, 29). No associations were observed between hs-CRP concentration and regular use of supplements containing methylsulfonylmethane, garlic, ginkgo biloba, saw palmetto, or pycnogenol. These results suggest that glucosamine and chondroitin supplements are associated with reduced inflammation in humans and provide further evidence to support an inverse association between use of fish oil supplements and inflammation. It is important to further investigate the potential antiinflammatory role of these supplements, as there is a need to identify safe and effective ways to reduce inflammation and the burden of inflammation-related diseases such as cancer and cardiovascular disease.

Social status, glucocorticoids, immune function, and health: can animal studies help us understand human socioeconomic-status-related health disparities?

For humans in developed nations, socioeconomic status (SES)--relative income, education and occupational position in a society--is a strong predictor of morbidity and mortality rates, with increasing SES predicting longer life span (e.g. Marmot et al., 1991). Mechanisms underlying this relationship have been examined, but the relative role of each mechanism still remains unknown. By understanding the relative role of specific mechanisms that underlie dramatic health disparities between high and low social status individuals we can begin to identify effective, targeted methods to alleviate health disparities. In the current paper, we take advantage of a growing number of animal studies that have quantified biological health-related correlates (glucocorticoid production and immune function) of social status and compare these studies to the current literature on human SES and health to determine if and how animal studies can further our understanding of SES-associated human health disparities. Specifically, we compared social-status related glucocorticoid production and immune function in humans and animals. From the review, we show that our present understanding of the relationships between social status and glucocorticoid production/immune function is still growing, but that there are already identifiable parallels (and non-parallels) between humans and animals. We propose timely areas of future study focused on (1) specific aspects of social status that may influence stress-related physiology, (2) mechanisms underlying long-term influences of social status on physiology and health, and (3) intervention studies to alleviate potentially negative physiological correlates of social status.

The social patterns of a biological risk factor for disease: race, gender, socioeconomic position, and C-reactive protein

OBJECTIVE

Understand the links between race and C-reactive protein (CRP), with special attention to gender differences and the role of class and behavioral risk factors as mediators.

METHOD

This study utilizes the National Social Life, Health, and Aging Project data, a nationally representative study of older Americans aged 57-85 to explore two research questions. First, what is the relative strength of socioeconomic versus behavioral risk factors in explaining race differences in CRP levels? Second, what role does gender play in understanding race differences? Does the relative role of socioeconomic and behavioral risk factors in explaining race differences vary when examining men and women separately?

RESULTS

When examining men and women separately, socioeconomic and behavioral risk factor mediators vary in their importance. Indeed, racial differences in CRP among men aged 57-74 are little changed after adjusting for both socioeconomic and behavioral risk factors with levels 35% higher for black men as compared to white men. For women aged 57-74, however, behavioral risk factors explain 30% of the relationship between race and CRP.

DISCUSSION

The limited explanatory power of socioeconomic position and, particularly, behavioral risk factors, in elucidating the relationship between race and CRP among men, signals the need for research to examine additional mediators, including more direct measures of stress and discrimination.

Associations between transition-specific stress experience, nocturnal decline in ambulatory blood pressure, and C-reactive protein levels among transgender men

OBJECTIVES

To characterize challenges experienced during stages of female-to-male sex transition and investigate associations between transition-specific measures of psychosocial stress, nocturnal decline in ambulatory blood pressure (amBP), and changes in C-reactive protein (CRP) levels.

METHODS

For this biocultural study, 65 healthy transmen who were using testosterone (T) therapy participated in interviews to assess transition-specific stress experience. They provided perceived stress scores, self-esteem scores, 24-h amBP measures, salivary samples for T levels, and a blood spot for CRP levels. Psychosocial stress was examined in relation to amBP and CRP using linear regression while adjusting for age, body mass index, and smoking.

RESULTS

There were no differences in mean levels of amBP in association with stage of transition. Men reporting stress associated with being "out" as transgender had significantly diminished nocturnal decline in systolic and diastolic amBP compared to men who did not report such stress. The associations remained significant when examined among men in stages 1 and 2 (≤ 3 years on T), but not among men in stage 3 (>3 years on T) of transition. Men reporting stress related to "passing" as someone born male had higher CRP levels than those who did not report such stress. The association remained significant when examined among men in stages 2 and 3 (>0.5-3 years on T).

CONCLUSION

Measures of stress that captured individuals' experiences of gender liminality were associated with diminished nocturnal decline in amBP and increased levels of CRP. There are significant differences between men grouped into different stages of the transition process.

Ischaemic manifestations in giant cell arteritis are associated with area level socio-economic deprivation, but not cardiovascular risk factors

OBJECTIVES

To determine whether ischaemic manifestations of GCA are associated with pre-existing hypertension, atherosclerosis or area-level socio-economic deprivation.

METHODS

We conducted an observational study of rheumatologist/ophthalmologist-diagnosed GCA in eight UK centres. The main outcome measure was ischaemic manifestations observed during active GCA: visual loss/blurring, aura, diplopia, jaw/tongue/limb claudication, cerebral/myocardial ischaemia or scalp necrosis.

RESULTS

Out of 271 patients, 222 had ischaemic manifestations. Adjusted odds ratios (ORs) for the influence of hypertension and atherosclerosis were 1.6 (95% CI 0.8, 3.1) and 1.5 (0.6, 3.5). The most striking finding was an association of ischaemic manifestations with increasing Index of Deprivation 2007 score: OR 4.2 (95% CI 1.3, 13.6) for the most-deprived quartile compared with the least-deprived quartile. Similar effect sizes were seen within each recruitment centre. Deprivation was associated with smoking and negatively associated with previous polymyalgia. However, neither of these variables, nor hypertension or atherosclerosis, appeared responsible for mediating the effect of deprivation on ischaemic complications. Smoking was not associated with ischaemic manifestations. Median symptom duration before treatment was 30 days; after adjusting for symptom duration, the OR for ischaemic complications was 3.2 (95% CI 1.0, 10.8) for the most-deprived quartile compared with the least-deprived quartile.

CONCLUSIONS

In GCA, area-level socio-economic deprivation was associated with ischaemic manifestations: this was not mediated by traditional cardiovascular risk factors. These findings are novel and require replication. Delay between first symptoms and treatment may play a role. Public awareness campaigns about GCA should aim especially to engage individuals living in more deprived areas to encourage early presentation and prompt treatment.

High-sensitivity C-reactive protein concentrations among patients with and without diabetes in a multiethnic population of Singapore: CREDENCE Study

OBJECTIVES

To determine whether high-sensitivity C-reactive protein (hs-CRP) concentrations differ between Chinese, Malays, and Indians with and without type 2 diabetes mellitus and to look for an association with demographic, metabolic and therapeutic variables.

METHODS

Phase 1: We retrieved records of 50 Chinese, 51 Malay, and 67 Indian individuals who had routine health screening blood tests. Phase 2: We recruited 111 Chinese, 68 Malays, and 67 Indians with type 2 diabetes mellitus and measured their hs-CRP in addition to standard laboratory tests.

RESULTS

Phase 1: The median hs-CRP was 0.6 mg/L (0.2-6.2) in Chinese, 1.2 mg/L (0.2-7.9) in Malays, and 1.9 mg/L (0.2-10.0) in Indians. The Indians had higher hs-CRP compared to Chinese (P < 0.05) when adjusted for age, sex, body mass index (BMI), lipids, blood pressure, and smoking, and a significant correlation was seen between female sex, smoking status, fasting glucose and triglyceride concentration, and hs-CRP in all three ethnicities. Phase 2: The median hs-CRP was 1.2 mg/L (0.2-9.9) in Chinese, 2.2 mg/L (0.2-9.0) in Malays, and 2.3 mg/L (0.2-9.8) in Indians. Indians had higher hs-CRP when compared to Chinese (P < 0.05) and a significant correlation was seen between BMI, female gender, diabetes, and the use of metformin and hs-CRP in all three ethnicities (P < 0.05) when adjusted for the above variables and use of aspirin, angiotensin-converting enzyme inhibitor/angiotensin receptor blockers (ACE-I/ARB), statin, metformin, rosiglitazone, sulfonylurea, glinides, acarbose, and insulin.

CONCLUSION

hs-CRP concentrations are significantly higher in Indians compared to the Chinese (in both the diabetic and nondiabetic individuals) after adjustment for the various demographic, metabolic, and therapeutic variables.