Sex differences in the relationship between C-reactive protein and body fat

Serum 25-hydroxyvitamin D levels are inversely associated with systemic inflammation in severe obese subjects

Obesity is frequently characterized by a reduced vitamin D bioavailability, as well as insulin-resistance and a chronic inflammatory response. We tested the hypothesis of an independent relationship between serum concentrations of 25-hydroxyvitamin D (25[OH]D) and several circulating inflammatory markers in a cohort of severely obese individuals. Cross-sectional study was carried out among obese patients undergoing a clinical evaluation before bariatric surgery in our University Hospital. Serum 25(OH)D, fasting and post load glucose and insulin, high-sensitive C-reactive protein (hs CRP), fibrinogen, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), leptin, adiponectin and lipid profile were collected. Insulin-resistance was assessed by insulin sensitivity index (ISI). Total body fat (FAT kg), total percent body fat (FAT%) and truncal fat mass (TrFAT) were assessed with dual-energy X-ray absorptiometry. A total of 147 obese subjects (89 women, 37.8 ± 7.1 years) with mean body mass index (BMI) of 43.6 ± 4.3 kg/m(2) were enrolled. Patients in the lowest tertile of 25(OH)D were significantly more obese with a higher amount of TrFAT, more insulin-resistant, and had higher levels of fasting and post-challenge glucose (p < 0.05 for all). In a multivariate regression analysis, serum 25(OH)D was inversely related to significant levels of hs CRP, IL-6 and TNF-α after accounting for age, gender, season of recruitment, BMI, FAT kg and TrFAT (p < 0.01 for all). In extremely obese subjects, 25(OH)D serum concentrations are inversely associated with several biomarkers of systemic inflammation, regardless of the total quantity of fat mass.

Associations between trunk, leg and total body adiposity with arterial stiffness

BACKGROUND

Obesity and arterial stiffness are associated, but fat distribution patterns may be more strongly related to arterial stiffness than general obesity because of the possible increased inflammation associated with increased abdominal adiposity. The aims of this study were to examine whether fat patterning is associated with arterial stiffness, and determine whether these associations are mediated by low-grade inflammation.

METHODS

Adult participants from the Fels Longitudinal Study (228 males and 254 females) were assessed for brachial-ankle pulse wave velocity (BaPWV) to determine arterial stiffness. Dual energy X-ray absorptiometry was used to estimate fat percentage of the trunk and legs (e.g., TRUNKFAT% and LEGFAT%). High-sensitivity C-reactive protein (hs-CRP) levels were assayed as a general marker of inflammation. General linear regression analyses were used.

RESULTS

BaPWV was positively associated with TRUNKFAT% (r = 0.44 in men and r = 0.38 in women), whereas it was inversely related to LEGFAT% (r = -0.40 in men and r = -0.39 in women). In multiple regression analyses, each SD increase in TRUNKFAT% was associated with an ~1.03 m/s increase in BaPWV in both men and women. Each SD increase in LEGFAT% was related to a similar magnitude of decrease (1.03 m/s) in BaPWV in both sexes. The relationships of TRUNKFAT% and LEGFAT% with BaPWV were attenuated slightly when including hs-CRP in the models, but remained significant.

CONCLUSIONS

We found that trunk and leg fat are related to BaPWV in opposite directions when total body adiposity was accounted for. However, the associations between regional fat patterning and arterial stiffness did not appear to be mediated by low-grade inflammation.

Dysfunctional adiposity and the risk of prediabetes and type 2 diabetes in obese adults

CONTEXT

The risk of type 2 diabetes mellitus is heterogeneous among obese individuals. Factors that discriminate prediabetes or diabetes risk within this population have not been well characterized. A dysfunctional adiposity phenotype, characterized by excess visceral fat and insulin resistance, may contribute to diabetes development in those with obesity.

OBJECTIVE

To investigate associations between adiposity phenotypes and risk for incident prediabetes and diabetes in a multiethnic, population-based cohort of obese adults.

DESIGN, SETTING, AND PARTICIPANTS

Among 732 obese participants (body mass index ≥30) aged 30 to 65 years without diabetes or cardiovascular disease enrolled between 2000 and 2002 in the Dallas Heart Study, we measured body composition by dual energy x-ray absorptiometry and magnetic resonance imaging (MRI); circulating adipokines and biomarkers of insulin resistance, dyslipidemia, and inflammation; and subclinical atherosclerosis and cardiac structure and function by computed tomography and MRI.

MAIN OUTCOME MEASURES

Incidence of diabetes through a median 7.0 years (interquartile range, 6.6-7.6) of follow-up. In a subgroup of 512 participants with normal fasting glucose values at baseline, incidence of the composite of prediabetes or diabetes was determined.

RESULTS

Of the 732 participants (mean age, 43 years; 65% women; 71% nonwhite), 84 (11.5%) developed diabetes. In multivariable analysis, higher baseline visceral fat mass (odds ratio [OR] per 1 SD [1.4 kg], 2.4; 95% CI, 1.6-3.7), fructosamine level (OR per 1 SD [1.1 μmol/L], 2.0; 95% CI, 1.4-2.7), fasting glucose level (OR per 1 SD [1.1 μmol/L], 1.9; 95% CI, 1.4-2.6), family history of diabetes (OR, 2.3; 95% CI, 1.3-4.3), systolic blood pressure (OR per 10 mm Hg, 1.3; 95% CI, 1.1-1.5), and weight gain over follow-up (OR per 1 kg, 1.06; 95% CI, 1.02-1.10) were independently associated with diabetes, with no associations observed for body mass index, total body fat, or abdominal subcutaneous fat. Among the 512 participants with normal baseline glucose values, the composite outcome of prediabetes or diabetes occurred in 39.1% and was independently associated with baseline measurements of visceral fat mass; levels of fasting glucose, insulin, and fructosamine; older age; nonwhite race; family history of diabetes; and weight gain over follow-up (P < .05 for each) but not with measurements of general adiposity.

CONCLUSION

Excess visceral fat and insulin resistance, but not general adiposity, were independently associated with incident prediabetes and type 2 diabetes mellitus in obese adults.

The association between self-reported symptoms of recent airway infection and CRP values in a general population

C-reactive protein (CRP) is a much used biomarker for respiratory tract infection; however, the influence of airway infection on the CRP level in the general population has not been well described. The study aimed to evaluate the impact of recent symptoms of airway infection on the CRP level and how the predictive power of other known CRP predictors is influenced by taking respiratory symptoms into account. A total of 6,325 participants, aged 38-87 years, in the Tromsø Study, a repeated population-based survey, were examined with questionnaires, measurements of height and weight, spirometry, and high-sensitivity CRP analyses. The mean CRP value was 2.86 mg/L, and the geometric mean was 1.51 mg/L. Geometric means above 2.0 mg/L were found in the subgroups with the following characteristics: self-reported COPD, diabetes, recent symptoms of airway infection, forced expiratory volume in 1 s (FEV1) <80% predicted, body mass index (BMI) ≥30, and subjects treated with inhaled or oral corticosteroids. Among the subjects who reported recent airway infection, 10.5% had a CRP value of ≥10 mg/L, compared to 3.3% among the remaining participants. By multivariate analysis, BMI was the strongest independent predictor of the CRP level, followed by recent airway infection, FEV1% predicted, age, and current smoking. The study clearly demonstrates that a report of recent symptoms of airway infection strongly predicts the CRP level in the population. Such symptoms were shared rather equally between subgroups with increased CRP level, and the risk of being an important confounder in epidemiological studies is probably low. In the clinical setting, care should be taken when using the CRP level as a guide for medical prevention of chronic diseases.

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.

Gender, obesity and repeated elevation of C-reactive protein: data from the CARDIA cohort

C-reactive Protein (CRP) measurements above 10 mg/L have been conventionally treated as acute inflammation and excluded from epidemiologic studies of chronic inflammation. However, recent evidence suggest that such CRP elevations can be seen even with chronic inflammation. The authors assessed 3,300 participants in The Coronary Artery Risk Development in Young Adults study, who had two or more CRP measurements between 1992/3 and 2005/6 to a) investigate characteristics associated with repeated CRP elevation above 10 mg/L; b) identify subgroups at high risk of repeated elevation; and c) investigate the effect of different CRP thresholds on the probability of an elevation being one-time rather than repeated. 225 participants (6.8%) had one-time and 103 (3.1%) had repeated CRP elevation above 10 mg/L. Repeated elevation was associated with obesity, female gender, low income, and sex hormone use. The probability of an elevation above 10 mg/L being one-time rather than repeated was lowest (51%) in women with body mass index above 31 kg/m(2), compared to 82% in others. These findings suggest that CRP elevations above 10 mg/L in obese women are likely to be from chronic rather than acute inflammation, and that CRP thresholds above 10 mg/L may be warranted to distinguish acute from chronic inflammation in obese women.

Inflammatory markers and blood pressure: sex differences and the effect of fat mass in the CoLaus Study

Several studies have reported high levels of inflammatory biomarkers in hypertension, but data coming from the general population are sparse, and sex differences have been little explored. The CoLaus Study is a cross-sectional examination survey in a random sample of 6067 Caucasians aged 35-75 years in Lausanne, Switzerland. Blood pressure (BP) was assessed using a validated oscillometric device. Anthropometric parameters were also measured, including body composition, using electrical bioimpedance. Crude serum levels of interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and ultrasensitive C-reactive protein (hsCRP) were positively and IL-1β (IL-1β) negatively (P<0.001 for all values), associated with BP. For IL-6, IL-1β and TNF-α, the association disappeared in multivariable analysis, largely explained by differences in age and body mass index, in particular fat mass. On the contrary, hsCRP remained independently and positively associated with systolic (β (95% confidence interval): 1.15 (0.64; 1.65); P<0.001) and diastolic (0.75 (0.42; 1.08); P<0.001) BP. Relationships of hsCRP, IL-6 and TNF-α with BP tended to be stronger in women than in men, partly related to the difference in fat mass, yet the interaction between sex and IL-6 persisted after correction for all tested confounders. In the general population, the associations between inflammatory biomarkers and rising levels of BP are mainly driven by age and fat mass. The stronger associations in women suggest that sex differences might exist in the complex interplay between BP and inflammation.

Total tooth loss and systemic correlates of inflammation: role of obesity

Obesity and edentulism are both associated with multiple systemic disorders with an inflammatory background including periodontal diseases. This study aimed to evaluate the different impact of obesity on inflammation in dentate and toothless subjects. The data came from the population-based, cross-sectional study SHIP (Study of Health in Pomerania). We determined anthropometric measures including BMI, waist-to-hip ratio (WHR), diagnostic periodontal parameters, and systemic metabolites. It was shown that measures of systemic markers of inflammation and lipid or glucose metabolism (P < 0.001) were increased with higher WHR. When adjusted for age, sex, smoking, diabetes, education, physical activity, and last dentist's appointment, C-reactive protein (CRP), fibrinogen, and leukocyte count were significantly related to WHR increasing from the first to the fourth WHR quartile (P < 0.001) as well as to the BMI. In both dentate and edentulous subjects higher WHR contributes significantly to increasing systemic CRP and fibrinogen with sex differences. In toothless subjects, while still dependent on increasing WHR, the inflammatory markers CRP and fibrinogen were higher than in dentate subjects, thereby revealing effect modification between sex and edentulism (P < 0.010). In conclusion, subjects with total tooth loss, although devoid of periodontal inflammation, may exhibit increased levels of systemic inflammatory mediators. Possible implications are discussed with respect to obesity and its relationship to inflammation.

Contribution of gender and body fat distribution to inflammatory marker concentrations in apparently healthy young adults

OBJECTIVE

This cross-sectional study assessed the potential contribution of gender, body fat distribution, and their interactions to some inflammatory marker concentrations [C-reactive protein (CRP), complement factor 3 (C3), and ceruloplasmin (Cp)] in young adults.

METHODS

Measurements included body composition, lifestyle features, blood biochemical and selected inflammatory markers on 317 healthy subjects [122 males/195 females; 22 ± 3 years; 22.1 ± 2.8 kg/m(2) (mean ± SD)].

RESULTS

Women had significantly higher CRP and Cp concentrations than men. No gender difference was noted in C3 concentrations. In a multivariate model of the whole sample, body fat (BF), waist circumference (WC) and the sex × WC interaction term presented the highest R (2) for variance of CRP (11%), C3 (2%), and Cp (12%), respectively. In regression models separated by sex, BF was the adiposity indicator that explained the variability of CRP in men (13%) and women (7%). WC was the only variable significantly associated with C3 concentrations in women (3%). BF presented the highest partial R (2) for Cp in men (8%) and WC in women (16%).

CONCLUSION

Our findings indicate a relevant interaction between gender and body fat distribution on the variance of CRP, C3, and Cp concentrations in apparently healthy young adults.

Sex differences in the relationship between inflammatory and hemostatic biomarkers and metabolic syndrome: British 1958 Birth Cohort

BACKGROUND

Circulating levels of C-reactive protein (CRP), fibrinogen, fibrin D-dimer, tissue plasminogen activator antigen (t-PA) and von Willebrand factor (VWF) are associated with incident coronary heart disease (CHD). However, their associations with metabolic syndrome and its components in large populations of men and women have not been well defined.

OBJECTIVES

We compare the sex associations of these biomarkers with established CHD risk factors, metabolic syndrome and its components in a large cohort.

PATIENTS AND METHODS

8302 men and women aged 45 years from the British 1958 birth cohort provided a blood sample. Analyses were restricted to 3457 men and 3464 women with complete data on all risk factors and no history of cardiovascular disease. Multiple regression analyses adjusted for smoking, social class, alcohol consumption and variables related to biomarker measurement error.

RESULTS

Adjusted sex differences in levels of all biomarkers (except VWF) varied according to presence/absence of metabolic syndrome, its components and obesity (BMI ≥30 kg m(-) (2)). Associations in women were up to twice as strong for CRP, fibrinogen and t-PA with markers of obesity (body mass index, waist circumference), blood pressure, blood lipids and metabolic syndrome. D-dimer showed weaker associations and less heterogeneity by sex. There was no evidence of sex interaction in associations with VWF.

CONCLUSIONS

Associations between CRP, fibrinogen and t-PA and metabolic syndrome and its components were stronger in women than in men. Understanding the reasons for these differences across sex will be important in understanding the pathophysiology of cardiovascular and metabolic disease in men and women.

Evaluation of the combined use of adiponectin and C-reactive protein levels as biomarkers for predicting the deterioration in glycaemia after a median of 5.4 years

AIMS/HYPOTHESIS

Hypoadiponectinaemia and raised C-reactive protein (CRP) level are obesity-related biomarkers associated with glucose dysregulation. We evaluated the combined use of these two biomarkers in predicting the deterioration of glycaemia in a prospective study after a median of 5.4 years.

METHODS

In total 1,288 non-diabetic participants from the Hong Kong Cardiovascular Risk Factor Prevalence Study-2, with high-sensitivity CRP (hsCRP) and total adiponectin levels measured were included. OGTT was performed in all participants. Two hundred and six participants had deterioration of glycaemia at follow-up, whereas 1,082 participants did not.

RESULTS

Baseline age, hsCRP and adiponectin levels were significant independent predictors of the deterioration of glycaemia in a Cox regression analysis after adjusting for baseline age, sex, BMI, hypertension, triacylglycerols, 2 h post-OGTT glucose and homeostasis model assessment of insulin resistance index (all p < 0.01). The introduction of hsCRP or adiponectin level to a regression model including the other biomarker improved the prediction of glycaemic progression significantly in all participants, especially in women (all p < 0.01). The combined inclusion of the two biomarkers resulted in a modest improvement in model discrimination, compared with the inclusion of either one alone. Among participants with impaired fasting glucose/impaired glucose tolerance (IFG/IGT) at baseline, hsCRP and adiponectin levels were not predictive of progression or improvement of glycaemic status.

CONCLUSIONS/INTERPRETATION

Adiponectin and hsCRP levels are independent factors in predicting the deterioration of glycaemia, supporting the role of adiposity-related inflammation in the development of type 2 diabetes. Their combined use as predictive biomarkers is especially useful in women, but not in participants with IFG/IGT.

Adipose tissue mass and location affect circulating adiponectin levels

AIMS/HYPOTHESIS

Plasma levels of adiponectin are inversely associated with body mass. We hypothesised that adipose tissue distribution and body composition influences adiponectin levels.

METHODS

We assessed plasma adiponectin concentrations and dual-energy X-ray absorptiometry (DEXA) measurements of body composition among 2,820 participants from the Dallas Heart Study.

RESULTS

Among both women and men, adiponectin levels were higher in whites than in either Hispanics or African-Americans (for women: median 9.99 μg/ml [25th,75th percentile 7.11, 13.77] vs 7.56 μg/ml [5.05, 9.98] vs 6.39 μg/ml [4.37, 9.41], respectively, p < 0.0001; for men: 6.43 μg/ml [4.66, 9.19] vs 5.55 μg/ml [3.64, 7.50] vs 5.03 μg/ml [3.39, 7.28], p < 0.0001). In univariate analysis, each individual component of body mass was inversely associated with adiponectin. After multivariate analysis, adiponectin levels were found to be positively associated with lower extremity fat, whether expressed in absolute mass (for women: β = 0.055, p < 0.0001; for men: β = 0.061, p < 0.0001), or as a relative proportion (for women: β = 0.035, p < 0.0001; for men: β = 0.034, p < 0.0001). This association was consistent across ethnicities. Conversely, adiponectin was negatively correlated with truncal fat, both in absolute (for women: β = -0.039, p < 0.0001; for men: β = -0.044, p < 0.0001) and relative terms (for women: β = -0.027, p < 0.0001; for men β = -0.033, p < 0.0001). At the extreme of body mass, higher degrees of lower extremity and truncal adiposity were associated with higher levels of adiponectin.

CONCLUSIONS/INTERPRETATION

These data suggest that the location of adipose depots differentially influences circulating adiponectin concentrations-a finding observed across ethnicity and sex. Gross measures of body mass alone do not adequately account for adiponectin levels. This supports a role of adiponectin as a mediator of the positive effects of lower extremity adiposity on improvements in insulin sensitivity.

CRP evolution pattern in CPAP-treated obstructive sleep apnea patients. Does gender play a role?

BACKGROUND-AIM

C-reactive protein (CRP) is directly implicated in atherogenesis and associated cardiovascular morbidity in patients with obstructive sleep apnea (OSA). Effective continuous positive airway pressure (CPAP) treatment has been shown to gradually decrease CRP levels and thus consequently improve disease-related cardiovascular morbidity. However, the influence of gender on the CRP evolution pattern has never been assessed before. The aim of our study was to investigate possible gender differences in CRP evolution in OSA patients 3 and 6 months after the start of effective CPAP treatment.

METHODS

The study population consisted of 436 patients (252 males/184 females) with newly diagnosed moderate to severe OSA and good CPAP compliance assessed by a thorough follow up. High-sensitivity C-reactive protein (hs-CRP) was assessed before CPAP initiation and at the third and sixth month of the follow-up period.

RESULTS

C-reactive protein values showed a statistically significant decrease at the third and sixth month of CPAP therapy [initial values 0.79 ± 0.65 mg/dL versus 0.70 ± 0.52 mg/dL (p < 0.05) after 3 months and 0.30 ± 0.33 mg/dL (p < 0.001) after 6 months of CPAP therapy]. When patients were divided into males and females, the above evolution pattern was changed. At the third month time point, the CRP values showed a statistically significant decrease only in males (from 0.74 ± 0.53 mg/dL to 0.61 ± 0.5 mg/dL, p < 0.01) while females showed only minimal and insignificant changes (from 0.87 ± 0.79 mg/dL to 0.83 ± 0.51 mg/dL, p > 0.05). After 6 months' treatment, CRP decreased significantly in both genders (males from 0.74 ± 0.53 mg/dL to 0.28 ± 0.32 mg/dL, p < 0.001 and females from 0.87 ± 0.79 mg/dL to 0.34 ± 0.36 mg/dL, p < 0.001).

CONCLUSION

Our results suggest a delay in the normalization of CRP levels in females despite effective CPAP treatment. A time period of at least 6 months appeared to be required in women in order to reduce CRP levels and consequent cardiovascular risk. In contrast, CPAP's protective role in males is achieved at an earlier time point. Gender-related hormonal and genetic factors may influence the above CRP evolution pattern.

Therapeutic approaches to obesity

OPINION STATEMENT

Obesity in the United States has become a public health crisis, with one third of the US population having a body mass index ≥30 kg/m(2). Given the profound impact of obesity on cardiovascular disease (CVD), studies of lifestyle modification, pharmacotherapy, and surgical interventions must be reappraised to better define the roles of these approaches in preventing cardiovascular events. Recent clinical trials have attempted to quell the debate over macronutrient composition versus caloric restriction in the dietary approach to weight loss. Our interpretation of these results is that caloric reduction and adherence to diets are of greater consequence than the particular dietary content for weight reduction. For cardiovascular risk factor modification, however, specific macronutrient composition of the diet may have additional impact outside weight loss, although the ultimate relationship between various dietary macronutrients and clinical cardiovascular outcomes is unclear. Although pharmacotherapy has been used for decades to treat obesity, there currently are limited options and recurrent cautionary tales; therefore, we use these agents sparingly. Sibutramine, one of only two medications approved by the US Food and Drug Administration for the long-term treatment of obesity, recently came under intense scrutiny because of a possible increase in cardiovascular events, and it now is contraindicated in patients with established CVD. Orlistat and its over-the-counter form, Alli (GlaxoSmithKline, Research Triangle Park, NC), can induce modest weight loss but frequently are not tolerated because of unpleasant gastrointestinal side effects. Fortunately, there are new medications in phase 3 clinical trials that hold promise as potential alternatives for obesity treatment. Finally, bariatric surgery for morbid obesity refractory to lifestyle interventions has become considerably more common. Surgery can effectively reduce body weight and treat cardiovascular risk factors, particularly diabetes, with acceptable complication rates and should be considered a viable option for appropriate patients. Ongoing clinical trials will clarify the impact of bariatric surgery on cardiovascular events and mortality, as well as the role of surgery as a treatment option that may be considered earlier than currently recommended.

Central obesity and smoking are key modifiable risk factors for elevated C-reactive protein in Asian individuals who are not eligible for statin therapy

Objective:

Statin therapy reduces coronary heart disease (CHD) and mortality in individuals with elevated C-reactive protein (CRP) but low-density lipoprotein cholesterol below the threshold at which statin therapy is recommended. We determined the proportion of individuals with elevated CRP in whom statin therapy was not indicated, and examined predictors for elevated CRP in a multi-ethnic Asian population.

Design:

We studied 3404 participants (Chinese, Malays and Asian-Indians) without a history of hypercholesterolemia living in Singapore (mean age±s.d.: 48.9±11.2 years). Eligibility for statin therapy was determined based on the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III (ATPIII)) guideline. CRP was measured by high-sensitivity enzyme-linked immunosorbent assay method. CRP level greater than 2 mg l⁻¹ was considered as elevated.

Results:

Elevated CRP was found in 29.3% participants who were not eligible for statin therapy (n=2974). Elevated CRP was more common in females and amongst those of Malay or Asian-Indian ethnicity. Compared with participants with low CRP, those with elevated CRP were shown to have higher levels of obesity, blood pressure, triglyceride and insulin resistance (IR), but lower high-density lipoprotein cholesterol levels (all Ps<0.001). After multivariate analysis, gender (odds ratio (OR) 3.34 for females), ethnicity (Malay OR 1.57, 95% confidence interval (CI) 1.25–1.96; Asian-Indian OR 1.97, 95% CI 1.55–2.50), waist circumference (OR 1.06, 95% CI 1.05–1.07), smoking (OR 1.49, 95% CI 1.08–2.05) and IR (OR 1.14, 95% CI 1.07–1.22) were significant predictors of CRP (all Ps--values<0.05).

Conclusion:

Routine measurement of CRP identifies a substantial number of Asian individuals at risk of CHD in whom statin therapy is not currently indicated, particularly in women and certain ethnic groups (Malays and Asian Indians). Weight loss and smoking cessation are important measures to reduce the proportion of individuals with elevated CRP.

Abdominal obesity and other risk factors largely explain the high CRP in indigenous Australians relative to the general population, but not gender differences: a cross-sectional study

Background

Previous studies reported high C-reactive protein (CRP) levels in Indigenous Australians, which may contribute to their high risk of cardiovascular disease. We compared CRP levels in Indigenous Australians and the general population, accounting for obesity and other risk factors.

Methods

Cross-sectional study of CRP and risk factors (weight, height, waist and hip circumferences, blood pressure, lipids, blood glucose, and smoking status) in population-based samples from the Diabetes and Related conditions in Urban Indigenous people in the Darwin region (DRUID) study, and the Australian Diabetes, Obesity and Lifestyle study (AusDiab) follow-up.

Results

CRP concentrations were higher in women than men and in DRUID than AusDiab. After multivariate adjustment, including waist circumference, the odds of high CRP (>3.0 mg/L) in DRUID relative to AusDiab were no longer statistically significant, but elevated CRP was still more likely in women than men. After adjusting for BMI (instead of waist circumference) the odds for elevated CRP in DRUID participants were still higher relative to AusDiab participants among women, but not men. Lower HDL cholesterol, impaired glucose tolerance (IGT), and higher diastolic blood pressure were associated with having a high CRP in both men and women, while current smoking was associated with high CRP in men but not women.

Conclusions

High concentrations of CRP in Indigenous participants were largely explained by other risk factors, in particular abdominal obesity. Irrespective of its independence as a risk factor, or its aetiological association with coronary heart disease (CHD), the high CRP levels in urban Indigenous women are likely to reflect increased vascular and metabolic risk. The significance of elevated CRP in Indigenous Australians should be investigated in future longitudinal studies.

Opposite associations of trunk and leg fat depots with plasma ferritin levels in middle-aged and older Chinese men and women

Background

Few data have been published on the associations of ferritin with trunk and leg fat depots. We aimed to investigate these associations in a Chinese population.

Methodology

Trunk fat mass and leg fat mass were determined in a cross-sectional sample of 1,150 Chinese (479 men and 671 women) aged 50–70 years by dual-energy X-ray absorptiometry scan. Fasting plasma ferritin was measured.

Principal Findings

Plasma ferritin was positively correlated with waist circumference, waist-to-hip ratio, total body fat and trunk fat mass, but inversely correlated with leg fat mass in men (r = 0.16, 0.26, 0.19, 0.22 and −0.12, respectively, all P<0.05) and women (r = 0.16, 0.16, 0.08, 0.17 and −0.12, respectively, all P<0.05). Multivariate regression analysis showed that ferritin levels increased with larger trunk fat mass (β = 0.33 ± 0.08 for men and β = 0.21 ± 0.05 for women, both P<0.001) while decreased with larger leg fat mass (β = −0.12 ± 0.09, P = 0.15 for men; and β = −0.14 ± 0.05, P = 0.005 for women). Moreover, plasma ferritin levels decreased with increasing tertile of leg fat mass among each tertile of trunk fat mass.

Conclusion

This is the first study to report the opposite associations of trunk and leg fat depots with plasma ferritin levels.

Body composition as determinant of thrombin generation in plasma: the Hoorn study

OBJECTIVE

The association between obesity and cardiovascular disease and venous thromboembolism might, at least partially, be explained by a hypercoagulable state. The extent to which body fat mass and its distribution contribute to a hypercoagulable state is unknown. In this study, we investigated the association between body composition and thrombin generation and evaluated the potential mediating role of low-grade inflammation.

METHODS AND RESULTS

We studied 586 individuals from the Hoorn Study (mean age, 69.7 ± 6.5 years, 298 women) in whom body composition was assessed by whole body dual-energy absorptiometry. Thrombin generation was measured using the calibrated automated thrombogram. Multiple regression analyses showed a positive association between total body fat and thrombin generation in women but not in men. In addition, detailed analyses of regional body composition showed that central but not peripheral fat mass was associated with greater thrombin generation and that there was a trend toward an inverse association with peripheral lean mass. The reported positive associations were partially attenuated by low-grade inflammation, however.

CONCLUSIONS

Body fat mass, in particular a central pattern of fat distribution, is associated with higher levels of thrombin generation in elderly women but not in men. This association may partially be explained by adiposity-related low-grade inflammation, but this hypothesis needs to be further investigated in mechanistic/prospective studies.