Relation of C-reactive protein to features of the metabolic syndrome in normal glucose tolerant, impaired glucose tolerant, and newly diagnosed type 2 diabetic subjects

Salsalate Improves Postprandial Glycemic and Some Lipid Responses in Persons With Tetraplegia: A Randomized Clinical Pilot Trial With Crossover Design

Objectives

To investigate the effects of salsalate on fasting and postprandial (PP) glycemic, lipidemic, and inflammatory responses in persons with tetraplegia.

Methods

This study was a randomized, double-blind, cross-over design. It was conducted at a university laboratory. Ten males aged 25 to 50 years with SCI at C5-8 levels for ≥1 year underwent 1 month of placebo and salsalate (4 g/day) treatment. Blood samples were drawn before and 4 hours after breakfast and lunch fast-food meal consumption.

Results

Descriptive statistics indicate that fasting and PP glucose values were reduced with salsalate (pre-post mean difference, 4 ± 5 mg/dL and 8 ± 8 mg/dL, respectively) but largely unchanged with placebo (0 ± 6 mg/dL and -0 ± 7 mg/dL, respectively). Insulin responses were generally reciprocal to glucose, however less pronounced. Fasting free fatty acids were significantly reduced with salsalate (191 ± 216 mg/dL, p = .021) but not placebo (-46 ± 116 mg/dL, p = .878). Results for triglycerides were similar (25 ± 34 mg/dL, p =.045, and 7 ± 29 mg/dL, p = .464). Fasting low-density lipoprotein (LDL) levels were higher after salsalate (-10 ± 12 mg/dL, p = .025) but not placebo (2 ± 9 mg/dL, p = .403) treatment. Inflammatory markers were largely unchanged.

Conclusion

In this pilot trial, descriptive values indicate that salsalate decreased fasting and PP glucose response to fast-food meal challenge at regular intervals in persons with tetraplegia. Positive effects were also seen for some lipid but not for inflammatory response markers. Given the relatively "healthy" metabolic profiles of the participants, it is possible that salsalate's effects may be greater and more consistent in people with less favorable metabolic milieus.

Comorbidity and physical activity in people with paraplegia: a descriptive cross-sectional study

STUDY DESIGN

Descriptive cross-sectional study.

SETTING

The study was conducted in the Spinal Cord Injury Unit of the University Vall d'Hebron Hospital and in the Physical Education and Sports Department of the University of Valencia.

OBJECTIVES

The aim of this study was to quantify the presence of comorbidities in spinal cord injury (SCI) subjects who did or did not perform regular physical activity (PA) and to identify the relationship between PA and the level of comorbidity.

METHODS

The sample consisted of patients with complete motor SCI (T2-T12), who were fitted with an accelerometer attached to the non-dominant wrist for a period of 1 week. The clinical and blood analytic variables were selected by an expert panel.

RESULTS

In the exploratory analysis, we have found differences in the total number of pathologies between active and inactive patients, with fewer total pathologies in the active patient group. An association was found between the PA level and diabetes mellitus (; P=0.047; φ=0.25). We also observed an association between the cardioprotector level of high-density lipoprotein (HDL)-cholesterol and PA level (; P=0.057; Φ0.24).

CONCLUSIONS

Our results suggest that patients considered active showed lower total comorbidity than inactive patients and higher protection levels against developing cardiovascular comorbidity.

Association of serum high-sensitivity C-reactive protein with metabolic control and diabetic chronic vascular complications in patients with type 2 diabetes

AIMS

To determine an association between hs-CRP and metabolic control/diabetic chronic vascular complications (DCVCCxs) in the patients with type 2 diabetes (DM). In addition, the possibility of using hs-CRP levels to predict risk of DCVCCxs will also be validated.

METHODS

This cohort study randomly enrolled 608 patients with DM during the 2007-2008 study period. We also recorded basic laboratory findings at baseline and at one year, to include fasting plasma glucose, HbA1c, triglyceride, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and hs-CRP.

RESULTS

Logistic regressions of odds ratios between hs-CRP and DCVCCxs (coronary arterial disease, cerebrovascular disease, diabetic nephropathy, diabetic retinopathy, and diabetic peripheral neuropathy) showed significant correlations, except for cerebrovascular disease, as follows 0.2 (0.11-0.38), 0.09 (0.01-0.77), 0.06 (0.02-0.16), 0.31 (0.12-0.82), and 0.17 (0.07-0.43), respectively. Linear regression for changes in hs-CRP were significantly correlated with HbA1c (r=0.38), fasting plasma glucose (r=0.40), triglyceride (r=0.20), low-density lipoprotein cholesterol (r=0.12), and high-density lipoprotein cholesterol (r=-0.12). No correlation was found for total cholesterol (r=0.06). Based on receiver operating characteristic (ROC) analysis, the cut-off points for hs-CRP levels for prediction of DCVCCxs were 2.89, 2.25, 2.10, 2.25, and 2.82mg/L, for coronary arterial disease, cerebrovascular disease, diabetic nephropathy, diabetic retinopathy, and diabetic peripheral neuropathy, respectively.

CONCLUSIONS

Our data showed that DCVCCxs were associated with hs-CRP in patients with DM. The cut-off point for hs-CRP can be used to predict association with DCVCCxs. Well-controlled metabolic components in diabetic patients, especially HbA1c, fasting plasma glucose, and triglyceride may reduce the level of hs-CRP.

Serum high-sensitivity C-reactive protein as a biomarker in patients with metabolic syndrome: evidence-based study with 7284 subjects

BACKGROUND/OBJECTIVES

Metabolic syndrome (MetS) is characterized by abdominal obesity, dyslipidemia, hypertension and glucose intolerance, and is associated with an increased risk of developing cardiovascular disease (CVD), diabetes mellitus and related diseases. Circulating levels of inflammatory markers such as C-reactive-protein (CRP) have reported to be associated with CVD. Against this background, the prevalence of MetS is increasing globally, and thus predictive biomarkers are required for identification of MetS patients at an increased risk. Here we explored the value of CRP as a biomarker in 7284 subjects and also investigated which features of MetS have the greatest association with the hs-CRP level.

SUBJECTS/METHODS

The subjects were recruited from the Mashhad stroke and heart atherosclerotic disorder study. Anthropometric factors and biochemical parameters (for example, high-sensitivity CRP (hs-CRP), high-density lipoprotein/low-density lipoprotein, triglycerides (TGs) and fasting blood glucose (FBG)) were determined. Univariate and multivariate analyses were conducted to evaluate the association of hs-CRP and MetS.

RESULTS

Our results illustrated that the concentration of serum hs-CRP increased progressively with the number of MetS components, and subjects who fulfilled the criteria of MetS for waist circumference, TGs, blood pressure and FBG were found to have hs-CRP of 0.53, 0.38, 0.34 and 0.71 mg/l, respectively, higher than matched-subjects. Importantly, FBG had the greatest association with hs-CRP concentration.

CONCLUSIONS

Our data demonstrate the significant association between MetS components with hs-CRP, indicating that this association was cumulative by increasing the number of the defining features of MetS, supporting further studies to explore the value of emerging marker as a novel method for detecting individuals at high risk of developing MetS.

Atherosclerotic Cardiovascular Disease Risk in the HAART-Treated HIV-1 Population

Atherosclerotic cardiovascular disease (CVD), a leading cause of morbidity and mortality in the general population, is also an increasing cause for concern for HIV-infected patients. A number of risk factors for CVD are also associated with HIV disease and HIV therapy, particularly insulin resistance, metabolic dyslipidemia, and inflammation. For example, atherogenic dyslipidemia, a side effect of HIV therapy, is an established risk for CVD in the non-HIV-infected population. As our understanding of atherosclerotic disease evolves, new markers of CVD risk have been identified, including metabolic syndrome definitions and C-reactive protein, a marker of inflammation. Use of these markers, in association with established risk factor guidelines, may serve as important tools in helping HIV physicians implement drug regimens that allow optimum management of metabolic complications associated with HIV and HAART, and thereby reduce CVD risk. The objective of this article is to review the mechanisms of atherosclerotic CVD and to discuss risk factors and markers that can be applied in the evaluation and treatment of CVD in the HIV-positive population.

[The Relationship between High Sensitivity C-Reactive Protein and Metabolic Syndrome according to the Fasting Glucose Level at Medical Checkups.]

BACKGROUND

This study was performed to investigate the difference in high sensitivity C-reactive protein (hsCRP) and metabolic syndrome according to the fasting glucose level, especially between the groups of less than 100 mg/dL and 100-109 mg/dL, which were conventionally categorized into normal levels.

METHODS

Those who underwent routine medical checkups aged above 20 (male, 3,221; female, 3,334) at a Health Promotion Center (Seoul, Korea) were divided into normal fasting glucose group I (glucose <100 mg/dL), normal fasting glucose group II (glucose, 100-109 mg/dL), impaired fasting glucose group, and diabetes mellitus group. The hsCRP, obesity index, blood pressure, total cholesterol, triglyceride, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and lipoprotein(a) [Lp(a)] were compared among the groups. The hsCRP and the components of metabolic syndrome were compared.

RESULTS

The hsCRP level, age, obesity index, blood pressure, total cholesterol and triglyceride significantly increased along with the increment in fasting glucose level in the 4 groups. The hsCRP had a positive correlation with the fasting glucose level, age, and systolic blood pressure, while it had a negative correlation with HDL-C. The metabolic syndrome was more common in the group with a higher level of glucose.

CONCLUSIONS

The group with glucose level of less than 110 mg/dL, conventionally categorized into normal range, needs to be subdivided into a group of 100-109 mg/dL and a group of less than 100 mg/dL. The former group seems to require more efforts to have the glucose level to be maintained under the level of 100 mg/dL.

Cardiovascular disease, SCI and exercise: unique risks and focused countermeasures

PURPOSE

To summarise the spinal cord injury (SCI) specific profile of three cardiovascular disease risk factors (CVD): fasting dyslipidaemia, postprandial lipidaemia and vascular inflammation and to summarise exercise prescriptions that may attenuate each.

METHOD

NA.

RESULTS

NA.

CONCLUSIONS

At least three CVD risk factors have unique profiles in the SCI population. Fasting dyslipidaemia is characterised in the SCI population by depressed HDL cholesterol and normal or low total cholesterol. In the post-prandial state, persons with SCI exhibit an exaggerated triglyceride rise and delayed clearance compared to non-disabled persons. Finally, vascular inflammation, as indexed by C-reactive protein, is markedly elevated in SCI. Exercise may improve each, although the specific prescriptions differs. Fasting dyslipidaemia responds to 8 weeks of moderate intensity aerobic exercise performed 5 days weekly for 30 min daily. Post-prandial lipaemia treatment requires daily moderate or vigorous aerobic exercise, as the effect dissipates day by day. The daily exercise duration is proportional to fitness level, with total caloric expenditure emphasised rather than time. Finally, attenuating vascular inflammation in non-disabled persons requires moderate or vigorous exercise performed for ≥12 months, 5 days weekly for ≥45 min; with aerobic exercise plus resistance training more effective than aerobic exercise alone.

Association of adiposity, inflammation and atherosclerosis: the role of adipocytokines and CRP in Asian Indian subjects

BACKGROUND

To reveal the exact link between adipose tissue, inflammation, and cardiovascular disease (CVD), we studied the association of C-reactive protein (CRP) with insulin resistance and adipocytokines in Asian Indian subjects.

METHODS

Forty-one controls, 40 obese, and 53 type 2 diabetes (T2DM) patients (total 134) were recruited. Enzyme-linked immunoassay (ELISA) technique was used to determine serum CRP and adipocytokine concentrations. Serum insulin was measured by radioimmune assay, and insulin resistance index was calculated by the homeostasis model assessment (HOMA). Association of CRP with different adipocytokines and insulin resistance was assessed with univariate regression analysis.

RESULTS

Serum leptin, resistin, and CRP levels were significantly increased and adiponectin levels were significantly reduced in obese subjects. In T2DM patients, CRP levels were increased and adiponectin levels were significantly decreased but no difference in leptin and resistin levels were found compared to controls. An important finding of this study was the significantly reduced levels of leptin, adiponectin, and resistin in nonobese T2DM patients compared to their BMI-matched controls. CRP in all subjects showed a significant correlation with obesity parameters like BMI (P < 0.001), waist circumference (P < 0.01), body fat percentage (P < 0.01), HOMA-IR (P < 0.001), leptin (P < 0.05), and resistin (P < 0.01).

CONCLUSIONS

The association of CRP with insulin resistance, adipocytokines, and resistin reveals close links between inflammation, CVD, and adipose tissue. These findings provide an exciting therapeutic opportunity in cardiovascular disease by targeting various proinflammatory cascades in adipocytes.

Glycemic control modifies the association between microalbuminuria and c-reactive protein in Type 2 Diabetes Mellitus

Microalbuminuria and C-reactive protein reflect closely related components of the same disease process. The present study attempts to evaluate whether any association exists between C-reactive protein and microalbuminuria in Type 2 Diabetes Mellitus patients with poor and adequate glycemic control. It was observed that in diabetics with poor glycemic control, microalbuminuria showed a significant positive correlation with C-reactive protein and the prevalence of microalbuminuria was significantly more at elevated C-reactive protein levels. These parameters were not significant in subjects with adequately controlled disease. Further, there was a significant increase in levels of microalbuminuria in patients with poor glycemic control when compared to well-controlled diabetics at comparative levels of C-reactive protein. This study supports the hypothesis that endothelial dysfunction and inflammatory activity are involved in the pathogenesis of microalbuminuria and underscores the importance of glycemic control in the progression of inflammation in diabetes.

Cardiovascular disease in spinal cord injury: an overview of prevalence, risk, evaluation, and management

Cardiovascular disease is a growing concern for the spinal cord-injured (SCI) population. For long-term SCI, morbidity and mortality from cardiovascular causes now exceeds that caused by renal and pulmonary conditions, the primary causes of mortality in previous decades. Although risk estimates commonly used for ambulatory individuals have not been established from follow-up studies in SCI, nearly all risk factors tend to be more prevalent in SCI subjects compared with ambulatory subjects. These risks include a greater prevalence of obesity, lipid disorders, metabolic syndrome, and diabetes. Daily energy expenditure is significantly lower in SCI individuals, not only because of a lack of motor function, but also because of a lack of accessibility and fewer opportunities to engage in physical activity. Autonomic dysfunction caused by SCI is also associated with several conditions that contribute to heightened cardiovascular risk, including abnormalities in blood pressure, heart rate variability, arrhythmias, and a blunted cardiovascular response to exercise that can limit the capacity to perform physical activity. Thus, screening, recognition, and treatment of cardiovascular disease should be an essential component of managing individuals with SCI, and judicious treatment of risk factors can play an important role in minimizing the incidence of cardiovascular disease in these individuals. This article reviews the cardiovascular consequences of chronic SCI, including the prevalence of cardiovascular disease and risk factors unique to these individuals, and provides a synopsis of management of cardiovascular disease in this population.

Serum levels of interleukin 6, C-reactive protein, vascular cell adhesion molecule 1, and monocyte chemotactic protein 1 in relation to insulin resistance and glucose intolerance--the Chennai Urban Rural Epidemiology Study (CURES)

The aim of this cross-sectional study was to assess the association of insulin resistance (IR) with inflammatory molecules C-reactive protein (CRP), interleukin 6 (IL-6), vascular cell adhesion molecule 1 (VCAM-1), and monocyte chemotactic protein 1 (MCP-1) in urban South Indian subjects. The following groups were selected from the population-based Chennai Urban Rural Epidemiology Study: group 1 composed of 50 healthy subjects with normal glucose tolerance without IR; group 2 consisted of 50 normal glucose-tolerant subjects with IR as defined by homeostasis model assessment of IR (HOMA-IR); group 3 consisted of 50 subjects with impaired glucose tolerance (IGT); and groups 4 and 5 each comprised 50 newly diagnosed and known type 2 diabetic subjects, respectively. The inclusion criteria included nonsmokers; normal resting 12-lead electrocardiogram; and absence of angina, myocardial infarction, or history of any known vascular, infectious, or inflammatory diseases, and not on statins or aspirin. Normal glucose tolerance without IR had the lowest values of CRP, IL-6, and VCAM-1 (CRP, 1.32 mg/L; IL-6, 12.56 pg/mL; VCAM-1, 277 pg/mL) followed by normal glucose tolerance with IR (CRP, 2.25 mg/L; IL-6, 20.97 pg/mL; VCAM-1, 289 pg/mL), impaired glucose tolerance (CRP, 2.37 mg/L; IL-6, 22.11 pg/mL; VCAM-1, 335 pg/mL), newly diagnosed diabetic subjects (CRP, 3.24 mg/L; IL-6, 23.21 pg/mL; VCAM-1, 568 pg/mL), and the highest levels were in the known diabetic subjects (CRP, 4.08 mg/L; IL-6, 29.44 pg/mL; VCAM-1, 577 pg/mL). This trend was statistically significant (P < .001). However, monocyte chemotactic protein 1 did not show such a trend and did not differ significantly between groups. In nondiabetic subjects, Pearson correlation analysis revealed that CRP (r = 0.299; P < .001) and IL-6 (r = 0.180, P = .025) had a significant correlation with HOMA-IR. Monocyte chemotactic protein 1 did not show any correlation with HOMA-IR. Multiple linear regression analysis revealed CRP to be significantly associated with HOMA-IR (beta = .229; P < .001) and this was unaltered by the addition of waist and IL-6 into the model (beta = .158; P = .028). In conclusion, this study shows that in Asian Indians, inflammatory markers (CRP, IL-6, and VCAM-1) increase with increasing degrees of glucose intolerance.

High-sensitivity C-reactive protein is only weakly related to cardiovascular damage after adjustment for traditional cardiovascular risk factors

BACKGROUND

The independent prognostic value of high-sensitivity C-reactive protein (hsCRP) has been questioned, and consequently we decided to investigate whether hsCRP was associated with subclinical cardiovascular (CV) damage independently of traditional CV risk factors.

METHODS

In a population-based sample of 2028 apparently healthy individuals without prior stroke or myocardial infarction not receiving any CV, anti-diabetic or lipid-lowering treatment, aged 41, 51, 61 or 71 years, we measured in 1993 serum hsCRP, traditional CV risk factors (lifestyle, metabolic and hemodynamic) and assessed subclinical CV damage [atherosclerotic plaques in the carotid arteries, pulse wave velocity (PWV), urine albumin/creatinine ratio (UACR), left ventricular (LV) mass and ejection fraction].

RESULTS

Adjusting for age and gender in multiple regression analyses, higher log(hsCRP) was associated with higher logPWV (beta = 0.15) and log(left ventricular mass index) (LVMI) (beta = 0.09, both P < 0.001), LV relative wall thickness (beta = 0.07, P < 0.01), logUACR (beta = 0.04, P = 0.06) and more atherosclerotic plaques (beta = 0.06, P < 0.05). However, higher log(hsCRP) was only weakly associated with higher logPWV(beta = 0.06, P < 0.05) and more atherosclerotic plaques (beta = 0.04, P = 0.06) when adjusting for other significant CV risk factors, such as daily smoking (beta = 0.18), female gender (beta = -0.17), older age (beta = 0.11), lower log(high density lipoprotein cholesterol) (beta = -0.11, all P < 0.001); wider waist (beta = 0.17), higher body mass index (beta = 0.14), higher heart rate (beta = 0.06, all P < 0.01); and higher log(plasma glucose) (beta = 0.05, P < 0.05) (adj. R2 = 0.19, P < 0.001).

CONCLUSION

After adjustment for traditional CV risk factors hsCRP was only associated with PWV and atherosclerotic plaques, indicating a possible effect of low-grade inflammation on macrovascular damage. The close relationship between traditional CV risk factors and hsCRP suggested that hsCRP was an integrated CV risk marker early in the development of atherosclerosis.

Calcium supplementation does not affect CRP levels in postmenopausal women--a randomized controlled trial

INTRODUCTION

Epidemiological studies suggest that calcium supplementation may decrease the risk of cardiovascular disease.

METHODS

Since the inflammatory marker C-reactive protein (CRP) is a risk factor for cardiovascular disease, and CRP production is potentially responsive to parathyroid hormone, we measured high-sensitivity CRP at baseline and 12 months in a subset of healthy postmenopausal women participating in a randomized controlled trial of the effects of 1 g of calcium daily on the incidence of fractures.

RESULTS

At baseline, we found that CRP correlated positively with indices of body weight and fat and with bone mineral density (BMD) at the total body and total hip sites, but the associations between CRP and BMD were lost after adjustment for body weight. There were consistent associations between levels of CRP and markers of the metabolic syndrome (fat mass, plasma triglycerides, fasting glucose).

CONCLUSION

After 1 year of calcium supplementation, there was no difference between the groups in levels of CRP. We conclude that levels of CRP correlate with anthropometric and biochemical features of insulin resistance, but that they are neither predictive of BMD nor affected by 1 g of calcium supplementation in healthy postmenopausal women.

Prevalence and correlates of metabolic syndrome (MS) in older adults

Metabolic syndrome (MS) is known to increase risks for cardiovascular disease. Risks for cardiovascular disease also increase with aging. The aim of the study was to describe prevalence and correlates of MS in older adults. Patients aged 65 years and over without any acute illness that were referred to our geriatrics unite for comprehensive geriatric assessment were included in this cross-sectional study. MS was defined by using the WHO and the National Cholesterol Education Program (NCEP) definitions. The correlates were age, gender, low-grade inflammation as assessed by C-reactive protein (CRP) levels, high-homocysteine, total and LDL cholesterol, lipoprotein-a (Lip-a), apolipoprotein-A (Apo-A), apolipoprotein-B (Apo-B), nutrition point, coronary artery disease (CAD) and cerebrovascular event history. Total 1255 patients, 789 (62.9%) females, 466 (37.1%) males with a mean age of 71.8+/-6.3 years were included in our study. MS prevalence was 16.2% with WHO definition and 23.8% with NCEP definition. Prevalence of CAD in MS and non-metabolic syndrome (non-MS) patients was 38.4% versus 29.5% (p=0.010) in WHO and 35.3% versus 29.6% (p=0.066) in NCEP group, respectively. Prevalence of cerebrovascular event history was 11.3% versus 6.2% in WHO (p=0.008) and 9.9% versus 6.1% (p=0.026) in NCEP group, respectively. Multiple logistic regression analysis was performed to investigate the independent association of variables with the MS. Female sex, high-homocysteine, low-grade inflammation, CAD and cerebrovascular event history was found to be associated with both modified WHO and NCEP MS groups in the multivariate analysis. This study has shown that MS is common in elderly patients with strongly related to CAD and cerebrovascular events. Low grade inflammation as assessed by CRP and high-homocysteine level is strongly related to MS.

Relationship of serum high sensitivity C-reactive protein to metabolic syndrome and microvascular complications in type 2 diabetes

The high sensitivity C-reactive protein (hsCRP) is known to be a sensitive predictor of coronary heart disease and type 2 diabetes. This study evaluated the association between the serum hsCRP and the components of metabolic syndrome (MS) and microvascular complications in type 2 diabetes. Two hundred and sixty-nine patients with type 2 diabetes were enrolled. All the subjects underwent measurement of MS and carotid intima-media thickness (IMT). The serum hsCRP concentrations and the 24 h urine albumin excretion amounts were measured. Ophthalmoscope examinations and nerve conduction velocity tests were performed to evaluate microvascular complications. The hsCRP was significantly higher in the patients with MS than in those without (p=0.019). The serum hsCRP was significantly correlated with all the components of MS. There were no differences between the serum hsCRP levels of those with and without retinopathy and neuropathy. The serum hsCRP was correlated with the 24 h urine albumin excretion amount. Serum hsCRP level has a significant correlation with MS and might be used as the future criteria of MS. Among microvascular complications, only diabetic nephropathy is associated with the serum hsCRP level. It suggests that the inflammatory process plays a role in nephropathy in type 2 diabetes.

Behavioural treatments for chronic systemic inflammation: effects of dietary weight loss and exercise training

Persistent low-grade inflammation, as indicated by higher circulating levels of inflammatory mediators such as C-reactive protein, interleukin-6 and tumour necrosis factor-alpha, is a strong risk factor for several chronic diseases. There are data indicating that decreasing energy intake and increasing physical activity may be effective therapies for reducing overall inflammation. Evidence is strong that circulating levels of inflammatory markers are elevated with total and abdominal obesity, possibly owing to a higher secretion rate of cytokines by adipose tissue in obese people. Moreover, very-low-energy dietary weight loss reduces both circulating markers of inflammation and adipose-tissue cytokine production. Data from several large population-based cohorts show an inverse association between markers of systemic inflammation and physical activity or fitness status; small-scale intervention studies support that exercise training diminishes inflammation. Dietary weight loss plus exercise is likely more effective than weight reduction alone in reducing inflammation. To date, data from randomized, controlled trails designed to definitively test the effects of weight loss or exercise training, or both, on inflammation are limited. Future studies are required to define the amount of weight loss needed for clinically meaningful reductions of inflammation; in addition, fully powered and controlled studies are necessary to clarify the effect of exercise training on chronic, systemic inflammation.

Thematic review series: The Immune System and Atherogenesis. Lipoprotein-associated inflammatory proteins: markers or mediators of cardiovascular disease?

In humans, a chronically increased circulating level of C-reactive protein (CRP), a positive acute-phase reactant, is an independent risk factor for cardiovascular disease. This observation has led to considerable interest in the role of inflammatory proteins in atherosclerosis. In this review, after discussing CRP, we focus on the potential role in the pathogenesis of human vascular disease of inflammation-induced proteins that are carried by lipoproteins. Serum amyloid A (SAA) is transported predominantly on HDL, and levels of this protein increase markedly during acute and chronic inflammation in both animals and humans. Increased SAA levels predict the risk of cardiovascular disease in humans. Recent animal studies support the proposal that SAA plays a role in atherogenesis. Evidence is accruing that secretory phospholipase A(2), an HDL-associated protein, and platelet-activating factor acetylhydrolase, a protein associated predominantly with LDL in humans and HDL in mice, might also play roles both as markers and mediators of human atherosclerosis. In contrast to positive acute-phase proteins, which increase in abundance during inflammation, negative acute-phase proteins have received less attention. Apolipoprotein A-I (apoA-I), the major apolipoprotein of HDL, decreases during inflammation. Recent studies also indicate that HDL is oxidized by myeloperoxidase in patients with established atherosclerosis. These alterations may limit the ability of apoA-I to participate in reverse cholesterol transport. Paraoxonase-1 (PON1), another HDL-associated protein, also decreases during inflammation. PON1 is atheroprotective in animal models of hypercholesterolemia. Controversy over its utility as a marker of human atherosclerosis may reflect the fact that enzyme activity rather than blood level (or genotype) is the major determinant of cardiovascular risk. Thus, multiple lipoprotein-associated proteins that change in concentration during acute and chronic inflammation may serve as markers of cardiovascular disease. In future studies, it will be important to determine whether these proteins play a causal role in atherogenesis.

Augmentation de la concentration plasmatique de la protéine C-réactive dans le diabète de l’enfant et de l’adulte jeune

OBJECTIVE

To investigate whether high sensitivity C-reactive protein (hs CRP) levels are elevated in young type 1 diabetic patients and to determine the relationships with age, degree of metabolic control determined by glycated hemoglobin (HbA1c), blood lipids, and subclinical complications.

METHODS

High sensitivity CRP was determined in young type 1 diabetic patients and in healthy controls. Blood lipids and HbA1c were also determined. The patients were divided into 2 groups. In group A, patients were free from subclinical complications (retinopathy, nephropathy and neuropathy) and in group B, patients had at least one subclinical complication.

RESULTS

The hs CRP concentrations were significantly higher in the 126 diabetic patients (55 girls and 71 boys) than in the 52 controls (2.6+/-4mg/L vs 0.7+/-0.7mg/L; p<0.001). This difference persisted when comparing the normal subjects with the 81 patients of group A (2.0+/-3.1mg/L; p<0.01) and the 45 patients of group B (3.6+/-5.1mg/L; p<0.001). The hs CRP concentrations were significantly correlated with total cholesterol, total cholesterol/HDL-cholesterol ratio, and LDL cholesterol for the 2 groups of patients. In the patients of group A, significant correlations were observed between hs CRP and age or duration of diabetes. No correlation was observed between hs CRP levels and glycaemia, HbA1c and HDL-cholesterol in the two groups of patients.

CONCLUSION

Levels of hs CRP were 3-fold greater in diabetic patients without complications than in controls and 5-fold greater in diabetic patients with subclinical complications. High sensitive CRP therefore appears to be an interesting indicator of the risk for developing complications.

C-reactive protein, the metabolic syndrome, and prediction of cardiovascular events in the Framingham Offspring Study

BACKGROUND

Inflammation (assessed by C-reactive protein [CRP]) and the metabolic syndrome (MetS) are associated with cardiovascular disease (CVD), but population-based data are limited.

METHODS AND RESULTS

We assessed the cross-sectional relations of CRP to the MetS (National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, Adult Treatment Panel III definition) in 3037 subjects (1681 women; mean age, 54 years) and the utility of CRP and the MetS to predict new CVD events (n=189) over 7 years. MetS (> or =3 of 5 traits) was present in 24% of subjects; mean age-adjusted CRP levels for those with 0, 1, 2, 3, 4, or 5 MetS traits were 2.2, 3.5, 4.2, 6.0, or 6.6 mg/L, respectively (P trend <0.0001). In persons with MetS, age-adjusted CRP levels were higher in women than men (7.8 versus 4.6 mg/L; P<0.0001). MetS and baseline CRP were individually related to CVD events (for MetS: age-sex-adjusted hazard ratio [HR], 2.1; 95% CI, 1.5 to 2.8; for highest versus lowest CRP quartile: HR, 2.2; 95% CI, 1.4 to 3.5). Greater risk of CVD persisted for MetS and CRP even after adjustment in a model including age, sex, MetS (HR, 1.8; 95% CI, 1.4 to 2.5), and CRP (HR, 1.9; 95% CI, 1.2 to 2.9). The c-statistic associated with the age- and sex-adjusted model including CRP was 0.72; including MetS, 0.74; and including CRP and MetS, 0.74.

CONCLUSIONS

Elevated CRP levels are related to insulin resistance and the presence of the MetS, especially in women. Although discrimination of subjects at risk of CVD events using both MetS and CRP is not better than using either phenotype alone, both CRP and MetS are independent predictors of new CVD events.

Insulin and cancer

Obesity has recently been linked to mortality from the majority of cancers. The insulin/insulin-like growth factor (IGF) system may partly explain this effect. The metabolic syndrome, associated with hyperinsulinemia, may modulate this effect. Recent evidence supports the role of insulin and IGF-1 as important growth factors, acting through the tyrosine kinase growth factor cascade in enhancing tumor cell proliferation. In addition, the metabolic syndrome associated with a chronic inflammatory state and accompanying cytokine abnormalities may also contribute to tumor progression. Growing links between insulin and the etiology as well as prognosis in colon, prostate, pancreatic, and, particularly, breast cancer are reviewed. Of particular concern is the evidence that elevated IGF-1 may interfere with cancer therapy, adversely affecting prognosis. The role of insulin is of concern because of the increasing levels of obesity and the associated metabolic syndrome. Weight gain, through typical Western diet; limited levels of activity; and, more recently, stress-related changes in neuroendocrine function may lead to insulin resistance and hyperinsulinemia. The opportunity for a multidisciplinary approach involving nutrition, exercise, and stress reduction in an integrative setting may be crucial to limiting the insulin-resistant state and improving cancer outcomes.