Related Articles

BACKGROUND:

Coronary artery disease (CAD) occurs at an earlier age in South Asians compared with other ethnic groups. Infection and inflammation show a positive association with the disease.

OBJECTIVE:

To investigate the association of infection and inflammatory markers with premature CAD in the Indian Atherosclerosis Research Study population.

METHODS:

Antibody titres for Chlamydia pneumoniae, cytomegalovirus (CMV), Helicobacter pylori, herpes simplex virus and levels of interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP), fibrinogen and secretory phospholipase A2, were measured in 866 individuals (433 CAD patients and matched controls). All individuals were followed-up for recurrent cardiac events for four years. ANOVA was used to study the association of infection and inflammation with CAD.

RESULTS:

The present study found that the odds of CAD occurrence was 2.42 (95% CI 1.26 to 4.64; P<0.008), with all four infections and increased in the presence of hsCRP (OR 4.67 [95% CI 1.43 to 15.25]); P=0.011). Only anti-CMV antibody levels were a significant risk factor for CAD occurrence (OR 2.23 [95% CI 1.20 to 4.15]; P=0.011) and recurrent cardiac events (OR 1.94 [95% CI 0.85 to 4.45]; P=0.015). Mean values of the inflammatory biomarkers IL-6 (P=0.035), fibrinogen (P=0.014), hsCRP (P=0.010) and secretory phospholipase A2 (P=0.002) increased with CMV antibody levels. Incorporating hsCRP and IL-6 in the risk prediction models significantly increased the OR to 2.56 (95% CI 1.16 to 5.63; P=0.019) with a c statistic of 0.826.

CONCLUSIONS:

Pathogen burden, especially CMV infection in combination with inflammatory markers, is a significant predictor of CAD risk in the young Indian population.

Aims

Prospective studies have identified chronic inflammation as a risk factor for type 2 diabetes. However, it is not known whether infection by specific pathogens or having a greater “pathogen burden” is associated with diabetes. The aim of this study was to examine the cross-sectional relation of seropositivity to five pathogens (C. pneumoniae, cytomegalovirus, H. pylori, hepatitis A virus, herpes simplex virus) and prevalent diabetes.

Methods

Baseline data from a random sample of MultiEthnic Study of Atherosclerosis (MESA) participants (n=1,000; age: 45-84) were used. Diabetes was defined by ADA 2003 criteria, and “pathogen burden” by the number of pathogens (0–5) for which an individual was seropositive. Logistic regression was used to test differences in diabetes prevalence by seropositivity. Linear regression was used to explore associations between pathogen seropositivity and the inflammation markers CRP, IL-6, and fibrinogen.

Results

Diabetes prevalence was 12.7%, while seropositivity for C. pnuemoniae was 76%, cytomegalovirus 77%, H. pylori 45%, hepatitis A 58%, and herpes simplex virus 85%. 72% were seropositive for ≥3 pathogens. In crude analyses, the prevalence of diabetes was higher among those with a pathogen burden ≥3, and with seropositivity to cytomegalovirus, H. pylori, hepatitis A, and herpes simplex virus. After adjustment for demographic covariates (particularly race) all associations became nonsignificant. Pathogen seropositivity was also not related to inflammation marker levels.

Conclusions

Following demographic adjustments, no associations were observed between infection by several pathogens and diabetes status, suggesting no etiologic role for them in the occurrence of diabetes.

We examined the cross-sectional relationships of subclinical atherosclerosis – expressed by carotid intimal–medial thickness and coronary calcification – with antibodies to Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, herpes simplex virus, hepatitis A virus, and pathogen burden (number of positive pathogens). A random sample of 1056 individuals chosen from 5030 Multi-Ethnic Study of Atherosclerosis cohort participants were included. After multiple adjustment, no associations were found between atherosclerosis measures and either individual pathogens or pathogen burden. Interactions with inflammatory and endothelial function markers, demographic factors, BMI, high-density lipoprotein, diabetes, and smoking were also explored. The only interaction that was large, qualitative, statistically significant (P < 0.05) and in the expected direction was that between hepatitis A virus and soluble intercellular adhesion molecule-1 with regard to Agatston calcium score: the difference between hepatitis A virus-positive and hepatitis A virus-negative participants was −86 units in participants with soluble intercellular adhesion molecule-1 below the median, and +162 units in those with soluble intercellular adhesion molecule-1 equal or above the median. However, given the number of interactions that were explored, these results must be interpreted cautiously.

Findings from the present analyses do not provide support for an infectious etiology for subclinical atherosclerosis. However, the study’s limitations, which include its cross-sectional design and insufficient statistical power, suggest that inferences from its findings should be made cautiously.

Background

The biologic mechanisms linking socioeconomic position and psychosocial factors to cardiovascular disease (CVD) are not well understood. Immune response to persistent pathogens may be one of these mechanisms.

Methods

We analyzed cross-sectional data from the Multi-Ethnic Study of Atherosclerosis (N=999) composed of adults age 45–84. Log-binomial regression and ordinal logistic regression models were used to examine associations of socioeconomic factors and psychosocial factors with pathogen burden and immune response among those infected. Pathogen burden was assessed based on seroprevalence of Helicobacter pylori, cytomegalovirus, herpes simplex virus-1, and Chlamydia pneumoniae and antibody levels were used to characterize high immune response to all four pathogens.

Results

Low education was a strong and significant independent predictor of higher pathogen burden after adjustment for covariates (adjusted odds ratio (OR) 95% confidence interval (CI) 1.37, 1.19–1.57). Among subjects seropositive for all four pathogens, low education and a higher level of chronic psychosocial stress showed a positive association with higher antibody response, although associations were no longer significant in models with all covariates included (OR = 1.64, 95%CI 0.82–3.31 for lowest vs. highest educational category and OR= 1.29, 95%CI 0.96–1.73 for a one level increase in chronic stress).

Conclusion

Pathogen burden and heightened immune response may represent a biological pathway by which low socioeconomic position and chronic stress are related to increased rates of cardiovascular disease.

Background/Aims

Antibodies against infectious pathogens provide information on past or present exposure to infectious agents. While host genetic factors are known to affect the immune response, the influence of genetic factors on antibody levels to common infectious agents is largely unknown. Here we test whether antibody levels for 13 common infections are significantly heritable.

Methods

IgG antibodies to Chlamydophila pneumoniae, Helicobacter pylori, Toxoplasma gondii, adenovirus 36 (Ad36), hepatitis A virus, influenza A and B, cytomegalovirus, Epstein-Barr virus, herpes simplex virus (HSV)-1 and −2, human herpesvirus-6, and varicella zoster virus were determined for 1,227 Mexican Americans. Both quantitative and dichotomous (seropositive/seronegative) traits were analyzed. Influences of genetic and shared environmental factors were estimated using variance components pedigree analysis, and sharing of underlying genetic factors among traits was investigated using bivariate analyses.

Results

Serological phenotypes were significantly heritable for most pathogens (h2 = 0.17–0.39), except for Ad36 and HSV-2. Shared environment was significant for several pathogens (c2 = 0.10–0.32). The underlying genetic etiology appears to be largely different for most pathogens.

Conclusions

Our results demonstrate, for the first time for many of these pathogens, that individual genetic differences of the human host contribute substantially to antibody levels to many common infectious agents, providing impetus for the identification of underlying genetic variants, which may be of clinical importance.

Recent publications have suggested that infective pathogens might play an important role in the pathogenesis of atherosclerosis. This review focuses on these microorganisms in the process of atherosclerosis. The results of in vitro studies, animal studies, tissue studies, and serological studies will be summarised, followed by an overall conclusion concerning the strength of the association of the microorganism with the pathogenesis of atherosclerosis. The role of the bacteria Chlamydia pneumoniae and Helicobacter pylori, and the viruses human immunodeficiency virus, coxsackie B virus, cytomegalovirus, Epstein-Barr virus, herpes simplex virus, and measles virus will be discussed.

Key Words: atherosclerosis • Chlamydia pneumoniae • Helicobacter pylori

To date, there has been no convincing evidence for an association between Chlamydia pneumoniae or Helicobacter pylori and ectasia. In this case-control study, we have investigated the association of H. pylori and C. pneumoniae seropositivity with ectasia, severe coronary atherosclerosis, and normal vessels, which were so classified by coronary angiography. We have also evaluated the influence of these infections on inflammatory markers such as high-sensitive C-reactive protein (hsCRP) and interleukin 6 (IL-6).

Of the 796 patients undergoing coronary angiography for suspected ischemic heart disease, 244 patients were recruited. Of these, 91 had normal vessels, 88 had 3 or more obstructed vessels, and 65 had ectatic vessels without atherosclerosis. Eighty-seven atherosclerotic patients (98.9%) were positive for C. pneumoniae IgG, as were 64 ectatic patients (98.5%) and 76 controls (83.5%) (P < 0.001). Forty-two atherosclerotic patients (47.7%) were positive for C. pneumoniae IgM, as were 43 ectatic patients (66.2%) and 43 controls (47.3%) (P = 0.036). Seventy-two atherosclerotic patients (81.8%) were positive for H. pylori IgA, as were 26 ectatic patients (40.0%) and 44 controls (48.4%) (P < 0.001). High-sensitive CRP levels were significantly higher in ectatic patients (5.639 mg/L) than in controls (4.390 mg/L) (P = 0.032), and IL-6 levels were significantly higher in atherosclerotic patients (33.92 U/L) than in controls (14.01 U/L) (P < 0.001). Interleukin-6 levels were higher in H. pylori seropositive patients, and hsCRP levels were higher in C. pneumoniae seropositive patients, when compared with seronegatives.

We suggest that, as in atherosclerosis, C. pneumoniae infection is related to ectasia, with raised CRP levels.

PRO-- PCOS is associated with low-grade systemic inflammation as evidenced by elevation of multiple markers of inflammation such as C-reactive protein, interleukin-18, monocyte chemoattractant protein-1 and white blood count as well as endothelial dysfunction and increased oxidative stress.

CON-- The evidence in support of the presence of chronic inflammatory state in the majority of women with PCOS is incontrovertible. It is apparent that PCOS is associated with a significant elevation of multiple markers of inflammation including CRP, IL-18, MCP-1, and white blood count. Furthermore, PCOS is associated with other derangements associated with inflammation such as increased oxidative stress and endothelial dysfunction. While the etiology of systemic inflammation in PCOS remains unclear, recent data raise the intriguing possibility of a link between PCOS, inflammation and chronic low grade infectious agents such as Chlamydia pneumoniae, Helicobacter pylori and pathogens inducing periodontal inflammation.

Background

The pathophysiological mechanisms that underlie health disparities by socioeconomic status and race/ethnicity are poorly understood. Promising new research suggests that the burden of persistent infection may influence adult disease risk and mortality. This article examines how multiple persistent infections cluster within individuals and how this clustering varies by socioeconomic position and race/ethnicity in U.S. adults.

Methods

We analyze data from the National Health and Nutrition Examination Survey III (N = 19,275) for adults aged 17–90 years. The clustering of infections within individuals is studied using tetrachoric correlations. Multiple indicator multiple cause models are used to analyze the infection burden construct as measured by seropositivity to Helicobacter pylori, cytomegalovirus, herpes simplex virus-1, and hepatitis B, focusing on the burden's distribution by socioeconomic position and race/ethnicity. The results are corroborated using ordered logistic regression for a commonly used count index of individual infections.

Results

Seroprevalence of individual persistent infections is positively correlated, suggesting common factors related to exposure or susceptibility. Education, income, and race/ethnicity are strong and significant independent predictors of infection burden in U.S. adults in all models.

Conclusion

The disproportionate burden of persistent infections among disadvantaged groups across all ages may be one biologic pathway by which low socioeconomic position is related to increased rates of morbidity and mortality in the United States.

Social support is associated with cardiovascular disease mortality, however the physiologic mechanisms underlying this relationship remains unspecified. This study evaluated the association of social support with inflammatory markers associated with cardiovascular risk: C-reactive protein (CRP), interleukin-6 (IL-6), and fibrinogen. We evaluated two competing models of the support-inflammation relationship: first, that low social support is directly associated with inflammation, and second, that high support acts to buffer the effect of stress on inflammation. Using data from the baseline interview of the Multi-Ethnic Study of Atherosclerosis (N = 6,814, 53% female, age 45–84 years) we assessed the independent and interacting associations of social support and stress with inflammation. Social support was measured by the Emotional Social Support Index. Stressors in multiple domains (work, family, finances, interpersonal) were assessed. Serum CRP, IL-6, and fibrinogen were analyzed from fasting samples using high-sensitivity assays. Multivariate linear regression, including models stratified by gender and age group (45 – 64 and 65 – 84 years), was used to assess the direct and buffering relationships between social support, stress, and inflammation. In bivariate analyses low social support was associated with higher levels of all three markers. In adjusted models, low support was associated with higher lnCRP (B: 0.15, 95% CI: 0.01, 0.30) among men but not women. High social support buffered the relationship between stress and CRP among middle-aged women only (P for interaction 0.042). Overall, social support was only modestly associated with inflammation in this relatively healthy sample, and these relationships varied by age and gender.

Background

That infections with certain pathogens, by initiating an inflammatory response, may contribute to the development of atherosclerosis is suggested by clinical and experimental evidence.

Aim

To analyse atherosclerotic plaques of the carotid artery, samples of apparently healthy greater saphenous veins and circulating leucocytes from the same individual patients for the presence of Helicobacter pylori and Mycoplasma pneumoniae.

Methods

Samples from 36 patients undergoing carotid endarterectomy for symptomatic carotid artery stenosis were analysed by polymerase chain reaction for the presence of DNA specific for H pylori and M pneumoniae. IgG antibody titres against H pylori and M pneumoniae and plasma levels of soluble E‐selectin, soluble intercellular adhesion molecule‐1 and soluble vascular cell adhesion molecule‐1 were determined.

Results

M pneumoniae‐specific DNA was detected in the atherosclerotic plaques of 13 of 36 (36.1%) patients, in the saphenous veins of 9 of 36 (25%) patients and in the leucocytes of 27 of 36 (75%) patients. No salient association was observed between the presence of M pneumoniae‐specific DNA in leucocytes and atherosclerotic plaques or veins. A marked correlation between the presence of M pneumoniae in the respective specimens and the studied inflammatory markers or the presence of anti‐M pneumoniae antibodies was not observed. H pylori‐specific DNA could not be detected in the specimens tested.

Conclusions

The absence of H pylori and the random distribution of M pneumoniae in tissue samples obtained from patients with symptomatic carotid artery stenosis do not support a role for these pathogens in the development of atherosclerosis due to a direct interaction of the bacteria with the vasculature.

Objective

To determine the prevalence of pathogens that cause sexually transmitted infections (STIs) in semen from asymptomatic male infertility patients with and without leukocytospermia (LCS), and associations between STIs, inflammatory markers and other semen variables.

Design

Retrospective, controlled study.

Setting

Center for Reproductive Medicine, Brigham and Women's Hospital, Boston, Massachusetts.

Patient(s)

241 male infertility patients undergoing routine semen analysis; 132 with LCS, and 109 without LCS.

Intervention(s)

None

Main Outcome Measure(s)

DNA from STI pathogens [human papillomavirus (HPV), cytomegalovirus (CMV), herpes simplex virus (HSV), human herpes virus type 6 (HHV-6), Epstein-Barr virus (EBV), hepatitis B virus (HBV) and Chlamydia trachomatis (CT)], routine semen parameters and markers of accessory gland and epididymal function and inflammation.

Results

STI DNA was detected in 45/241 (18.7%) of the samples (CMV 8.7%, HPV 4.5%, HHV-6 3.7%, HSV 3.7%, CT 2.5%, EBV 0.4%, and HBV 0%), with no difference in prevalence between LCS and non-LCS groups. STI DNA in semen was associated with a decrease in sperm concentration, motile sperm concentration, total sperm count and neutral α-glucosidase concentration, whereas LCS was associated with a decrease in total sperm count, % normal forms and fructose concentration.

Conclusion(s)

STI pathogen DNA was detected in semen from a high percentage of asymptomatic male infertility patients and was associated with poor semen quality. Efforts to diagnose and treat subclinical genital tract infections should be intensified.

Background

Chronic low-grade systemic inflammation is a key component in atherogenesis. Decreased heart rate variability (HRV), a strong predictor of cardiovascular events, has been associated with elevations in circulating levels of C-reactive protein (CRP), interleukin (IL)-6, and fibrinogen in apparently healthy individuals. We investigated whether decreased HRV is associated with inflammatory markers in patients with coronary heart disease (CHD).

Methods

We studied the relationship between HRV and CRP, IL-6, and fibrinogen in 862 outpatients with CHD. All participants provided fasting blood samples and underwent 24-h ambulatory monitoring to assess time-domain measures of HRV (MeanNN, SDNN, SDANN, and RMSSD). Regression analyses were adjusted for age, sex, ethnicity, body mass index, smoking, diabetes, beta blocker use, and cardiopulmonary history.

Results

MeanNN, SDNN, and SDANN were significantly and inversely associated with CRP and IL-6 levels in age-adjusted models and after adjustment for all covariates (p ≤ 0.02). MeanNN, SDNN, and SDANN were also inversely associated with fibrinogen levels in age-adjusted models (p < 0.03), but not significantly so in multivariable-adjusted models. Reduced vagal modulation of heart rate (RMSSD) was not significantly associated with any inflammatory measures.

Conclusions

Reduced cardiac autonomic control is associated with increased systemic inflammation in patients with stable CHD. This relationship was largely independent of important covariates.

Background

The metabolic syndrome together with insulin resistance and their consequences are basic factors in pathogenesis of atherosclerosis. Chronic infections with herpes simplex virus type 1 (HSV-1), cytomegalovirus (CMV), and Chlamydia pneumoniae are associated with the development of atherosclerosis and coronary heart disease. The infectious aspects of metabolic syndrome have not been investigated.

Methods

In a cross-sectional, population-based study, we used National Cholesterol Education Program (NCEP)-Adult Treatment Panel (ATP)-III criteria in 1791 subjects, aged 25 years and over, selected by cluster random sampling in three Iranian ports in the northern Persian Gulf. Sera were analyzed for IgG antibodies to Chlamydia pneumoniae, HSV-1, Helicobacter pylori (H. pylori) and CMV using ELISA.

Results

In multiple logistic regression analysis, of the infectious agents, CMV [OR = 1.81 (1.05–3.10); p = 0.03], H. pylori [OR = 1.50 (1.12–2.00); p = 0.007] and Chlamydia pneumoniae [OR = 1.69 (1.27–2.25); p < 0.0001] showed a significant association with the metabolic syndrome in men and HSV-1 [OR = 1.95 (1.22–3.11); p = 0.005], H. pylori [OR = 1.45 (1.09–1.94); 0.01] and Chlamydia pneumoniae [OR = 1.65 (1.23–2.21); p = 0.001] in women.

Conclusion

The metabolic syndrome, which occurs very frequently in the general population, has a significant association with prior infection with Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus and herpes simplex virus type 1. Hypothesis about participation of infection in pathogenesis of metabolic syndrome should be investigated.

Inflammation plays a pivotal role in all stages of atherosclerosis. Numerous inflammatory, lipid, and cytokines markers have been associated with coronary artery disease (CAD) risk but data directly comparing their predictive value are limited. Studies were carried to elucidate the role of high-sensitivity C-reactive protein (hsCRP), other inflammatory as well as lipid markers and their associations. Among 1021 subjects, comprising 774 CAD affected members from Indian Atherosclerosis Research Study (IARS), plasma hsCRP levels showed strong correlation with inflammatory markers, namely, IL6 (r = .373; P = <.0001), sPLA2 (r = .544; P = <.0001) as also with fibrinogen (r = .579; P = <.0001). Levels of hsCRP were higher among subjects affected by CAD who suffered a repeat coronary event as compared to those who remained event free and subjects in the top quartile of hsCRP (>3.58 mg/L) were found to have a fourfold higher risk. In conclusion, hsCRP appears to be an independent predictor of recurrent CAD events in Asian Indian population.

Background

The overall burden of prior infections may contribute to atherosclerosis and stroke risk. We hypothesized that serological evidence of common infections would be associated with carotid plaque thickness in a multi-ethnic cohort.

Methods

Antibody titers to five common infectious microorganisms (i.e. Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpesvirus 1 and 2) were measured among stroke-free community participants, and a weighted index of infectious burden (IB) was calculated based on Cox models previously derived from for the association of each infection with stroke risk. High-resolution carotid duplex Doppler studies were used to assess maximum carotid plaque thickness (MCPT). Weighted least squares regression was used to measure the association between IB and MCPT after adjusting for other risk factors.

Results

Serological results for all five infectious organisms were available in 861 participants with MCPT measurements available (mean age 67.2+/−9.6 yrs). Each individual infection was associated with stroke risk after adjusting for other risk factors. The IB index (n=861) had a mean of 1.00 ± standard deviation 0.35, median 1.08. Plaque was present in 52% of participants (mean 0.90+/−1.04 mm). IB was associated with MCPT (adjusted increase in MCPT 0.09 mm, 95% confidence interval 0.03–0.15 mm, per standard deviation increase of IB).

Conclusion

A quantitative weighted index of infectious burden, derived from the magnitude of association of individual infections with stroke, was associated with carotid plaque thickness in this multi-ethnic cohort. These results lend support to the notion that past or chronic exposure to common infections, perhaps by exacerbating inflammation, contributes to atherosclerosis. Future studies are needed to confirm this hypothesis and to define optimal measures of infectious burden as a vascular risk factor.

The presence of antibodies to rubella, cytomegalovirus and Toxoplasma gondii was determined at birth and at 6 months of age in a group of 147 infants with cord serum IgM levels ≥ 19.0 mg/dl and in 92 control infants. Maternal syphilis serology was determined in both groups as well. No significant differences in the prevalence or levels of antibodies to these pathogens were found between the two groups which might have led to the diagnosis of unsuspected intrauterine infection. Persistence of antibodies to 6 months of age was similar in the two groups, indicating that this is not a useful index of intrauterine infection.

Analysis of the results yielded the following data on the prevalence of antibodies to the pathogens studied: rubella virus, 90 and 75% seropositivity at birth and 6 months respectively; cytomegalovirus, 65 and 35%; and Toxoplasma gondii, 33% seropositivity at birth.

Inflammation and pulse wave velocity (PWV) are a potential risk factor and marker, respectively, for atherosclerosis in the primary prevention setting. Atherosclerosis is now generally accepted to be an inflammatory disorder of the arterial wall, and the high-sensitivity C-reactive protein (hs-CRP) level has been reported to be a strong predictor of cardiovascular events. High-sensitivity-CRP is associated with two factors related to inflammation: (1) the local production of CRP by atheromatous tissue or coronary artery smooth muscle cells and (2) adipose tissue as a potent source of inflammatory cytokines. Based on studies in North America and Europe, hs-CRP has been established as a cardiovascular risk factor and a cut-off value has been recommended. However, Japanese have lower hs-CRP values than their Western counterparts, partly because Japanese have a lower body mass index (BMI), which correlates positively to hs-CRP, and partly because lifestyle and genetic factors can affect hs-CRP values. Therefore, a cut-off value needs to be established by cohort studies for the Japanese population. Carotid-femoral PWV is most commonly measured by applanation tonometry, particularly in Europe, but this method is critically dependent upon the accurate placing of transducers over the arteries and is both time-consuming and complex. A novel device has been recently developed in Japan that measures brachial-ankle PWV (baPWV) using a volume-rendering method. Brachian-ankle PWV is a suitable screening method because of its technical simplicity and shorter measurement time. It is associated not only with conventional cardiovascular risk factors but also with new risk factors, such as inflammation, γ-glutamyltransferase, chronic kidney disease, and psychosocial factors. However, a suitable cut-off value has yet to be established.

Objective

Levels of acute phase reactants are impacted by age. To what extent cardiovascular risk associated with aging is due to an increase in the inflammatory burden is not known. We assessed the relationship with age of inflammatory markers, representing a) systemic (C-reactive protein [CRP], fibrinogen and serum amyloid-A [SAA]) and b) vascular (lipoprotein-associated phospholipase A2 [Lp-PLA2] and pentraxin-3 [PTX-3]) inflammation.

Methods and Results

We determined Lp-PLA2 mass and activity, CRP, fibrinogen, SAA, and PTX-3 levels and other CVD risk factors in 336 Caucasians and 224 African Americans. Levels of systemic inflammatory markers increased significantly with age in both ethnic groups (P<0.05 for all), while trend patterns of vascular inflammatory markers did not change significantly with age for either group. In multivariate regression models adjusting for confounding variables, age remained independently associated with a composite z-score for systemic, but not vascular inflammation (β=0.250, P<0.001 and (β=0.276, P<0.001, for Caucasians and African Americans respectively).

Conclusions

We report an increase in the systemic, but not vascular, inflammatory burden over age. Levels of both categories of inflammatory markers over age were similar across ethnicity after adjustment for confounders. Our results underscore the importance of age in evaluating inflammatory markers to assess cardiovascular risk.

Objective

Inflammatory markers predict coronary heart disease (CHD). However, associations with coronary artery calcium (CAC), a marker of subclinical CHD, are not established.

Methods

We examined cross-sectional associations of C-reactive protein (CRP), interleukin-6 (IL-6) and fibrinogen with CAC presence (Agatston score > 0 by computed tomography) in 6,783 Multi-Ethnic Study of Atherosclerosis (MESA) participants.

Results

In all participants, those in the highest, compared to lowest, quartile of CRP had a relative risk (RR, 95% confidence interval) of 1.13 (1.06-1.19; p<0.01) for CAC in age, sex and ethnicity adjusted models. For highest versus lowest quartiles, relative risks were 1.22 (1.15-1.30; p<0.01) for IL-6 and 1.18 (1.11-1.24; p<0.01) for fibrinogen. Adjusting for CHD risk factors (smoking, diabetes, blood pressure, obesity and dyslipidemia) attenuated RRs. RRs for CAC were 1.05 (0.99-1.12; p=0.63) for CRP, 1.12 (1.06-1.20; p<0.01) for IL-6 and 1.09 (1.02-1.16; p=0.01) for fibrinogen in multivariable adjusted models. Results were similar for men and women and across ethnic groups.

Conclusion

Inflammatory markers were weakly associated with CAC presence and burden in MESA. Our data support the hypothesis that inflammatory biomarkers and CAC reflect distinct pathophysiology.

Recent work in biodemography has suggested that life-time exposure to infection and inflammation may be important determinants of later-life morbidity and mortality. Early exposure to infections during critical periods can predispose individuals to chronic disease, in part through the reallocation of energy away from development needed for immune and inflammatory responses. Furthermore, markers of inflammation are known to vary by socioeconomic status in adults and may contribute to overall socioeconomic health inequalities, but little is known about how the sources of this inflammation over the life course. This paper uses novel biomarker data from the Third National Health and Nutrition Examination Survey (NHANES III) to test the association of the burden of common chronic infections (Helicobacter pylori (H. pylori), cytomegalovirus (CMV), herpes simplex virus-1 (HSV-1), hepatitis A and hepatitis B) with height-for-age and asthma/chronic respiratory conditions in U.S. children ages 6 and older, and the association of these chronic infections to children’s socioeconomic status. A higher burden of infection is found to be associated with lower height-for-age as well as an increased likelihood of asthma net of race/ethnicity, family income, and parental education. Children with lower family income, lower parental education, and non-white race/ethnicity have a higher likelihood of infection with several individual pathogens as well as the overall burden of infection. Differential exposure and/or susceptibility to infections may be one mechanism through which early social factors get embodied and shape later life health outcomes.

Background—Helicobacter pylori is a human pathogen that colonises the gastric mucosa and causes permanent gastric inflammation. 
Aims—To assess the symptoms of H pylori infection in an adult unselected population. 
Subjects—A random sample of 3589 adult Danes who were examined in 1982 and 1987 (n=2987). 
Methods—Abdominal symptoms within the preceding year were recorded at both attendances. Circulating IgG antibodies against H pylori in serum samples drawn in 1982 were measured by using in-house indirect enzyme linked immunosorbent assays (ELISA). 
Results—People with increased levels of IgG antibodies to H pylori were more likely than uninfected individuals to report heartburn (odds ratio (OR) = 1.26, 95% confidence interval (CI) 1.03-1.54) and abdominal pain characterised by daily length (OR= 1.33, 95% CI 0.92-1.91), nocturnal occurrence (OR = 1.62, 95% CI 1.19-2.19), spring aggravation (OR = 1.68, 95% CI 0.70-4.05), and no relation to meals (OR = 0.62, 95% CI 0.43-0.91) or stress (OR = 0.69, 95% CI 0.50-0.95). The inclusion of people with increased levels of IgG antibodies to H pylori, but without upper dyspepsia, at study entry significantly increased the likelihood of reporting upper dyspepsia at follow up (OR = 1.71, 95% CI 1.24-2.36). People with epigastric pain and increased levels of IgM antibodies to H pylori only indicative of acute H pylori infection were more likely to report nocturnal pain, heartburn, nausea, and vomiting. 
Conclusions—H pylori infection may precede the development of dyspepsia and is associated with a variety of gastrointestinal symptoms in people with no history of peptic ulcer disease. 



Keywords: epidemiology; Helicobacter pylori; non-ulcer dyspepsia; symptomatology; upper dyspepsia

Background

Inflammation and inflammatory biomarkers play an important role in atherosclerosis and cardiovascular disease. Little information is available, however, on time course of serum markers of inflammation after stroke.

Methods

First ischemic stroke patients ≥40 years old had levels of high-sensitivity C-reactive protein (hsCRP), serum amyloid A (SAA), and fibrinogen measured in plasma samples drawn at 1, 2, 3, 7, 14, 21 and 28 days after stroke. Levels were log-transformed as needed, and parametric and non-parametric statistical tests were used to test for evidence of a trend in levels over time. Levels of hsCRP and SAA were also compared with levels in a comparable population of stroke-free participants.

Results

Mean age of participants with repeated measures (n = 21) was 65.6 ± 11.6 years, and 13 (61.9%) were men, and 15 (71.4%) were Hispanic. Approximately 75% of patients (n = 15) had mild strokes (NIH Stroke Scale score 0–5). There was no evidence of a time trend in levels of hsCRP, SAA, or fibrinogen for any of the markers during the 28 days of follow-up. Mean log(hsCRP) was 1.67 ± 1.07 mg/L (median hsCRP 6.48 mg/L) among stroke participants and 1.00 ± 1.18 mg/L (median 2.82 mg/L) in a group of 1176 randomly selected stroke-free participants from the same community (p = 0.0252).

Conclusion

Levels of hsCRP are higher in stroke patients than in stroke-free subjects. Levels of inflammatory biomarkers associated with atherosclerosis, including hsCRP, appear to be stable for at least 28 days after first ischemic stroke.

Background & objectives:

Studies on cardiovascular diseases (CVD) in India have shown about 10-20 per cent of cases with no obvious risk factors, raising a suspicion of infections as a cause. There is a paucity of data on this possible role of infections. This study was, therefore, undertaken to find out the association between infection due to Chlamydia pneumoniae and other organisms and coronary artery disease (CAD).

Methods:

Patients with CAD were selected in group I (acute myocardial infarction, AMI) and group III (patients undergoing coronary artery bypass graft (CABG) surgery), and normal controls in group II. Routine biochemical, haematological and inflammatory tests [C-reactive protein (CRP), total leucocyte count (TLC), fibrinogen, ESR], serodiagnostic tests for IgA and IgG antibodies to C. pneumoniae, Helicobacter pylori, cytomegalovirus (CMV), Mycoplasma pneumoniae and Parvovirus B-19 by ELISA kits, C. pneumoniae antigen by microimmunofluorescence and PCR from endothelial tissue obtained at CABG were carried out. Aortic punch biopsies were done in patients who underwent CABG.

Results:

Acute MI patients had a significantly higher association with accepted cardiac risk factors, lipid profile, inflammatory and thrombogenic tests. IgG and IgA antibodies levels against C. pneumoniae were not significantly different in the controls as against the AMI group. However, C. pneumoniae antigen seropositive group had significant association with HDL cholesterol, lipid tetrad index (P<0.001) and with triglycerides. Parvovirus B antigen was detected in 8.3 per cent of tissue specimens by PCR and of 44 patients with AMI (6.8%) were also positive for parvovirus B-19 IgG antibodies.

Interpretation & conclusions:

There was no direct evidence of the involvement of C. pneumoniae and other infective agents and viruses in CAD. It is possible that such infections produce an indirect adverse effect on the lipid profile.

OBJECTIVE—To study possible associations between coronary heart disease and serological evidence of persistent infection with Helicobacter pylori, Chlamydia pneumoniae, or cytomegalovirus.
DESIGN—Population based, case-control study, nested within a randomised trial.
SETTING—Five general practices in Bedfordshire, UK.
INDIVIDUALS—288 patients with incident or prevalent coronary heart disease and 704 age and sex matched controls.
RESULTS—High concentrations of serum IgG antibodies to H pylori were present in 54% of cases v 46% of controls, with corresponding results for C pneumoniae seropositivity (33% v 33%), and cytomegalovirus seropositivity (40% v 31%). After adjustments for age, sex, smoking, indicators of socioeconomic status, and standard risk factors, the odds ratios (95% confidence intervals) for coronary heart disease of seropositivity to these agents were: 1.28 (0.93 to 1.75) for H pylori, 0.95 (0.66 to 1.36) for C pneumoniae, and 1.40 (0.96 to 2.05) for cytomegalovirus.
CONCLUSIONS—There is no good evidence of strong associations between coronary heart disease and serological markers of persistent infection with H pylori, C pneumoniae, or cytomegalovirus. To determine the existence of moderate associations between these agents and disease, however, larger scale studies will be needed that can keep residual confounders to a minimum.

 Keywords: ischaemic heart disease; Helicobacter pylori; Chlamydia pneumoniae; cytomegalovirus