High levels of cystatin C predict the metabolic syndrome: the prospective Malmö Diet and Cancer Study

Cystatin C Is a Predictor for Long-Term, All-Cause, and Cardiovascular Mortality in US Adults With Metabolic Syndrome

OBJECTIVE

This study examined the relationship between cystatin C (CysC) levels and all-cause, cardiovascular disease (CVD), and cancer mortality in US metabolic syndrome (MetS) patients.

METHODS

The 1999-2002 National Health and Nutrition Examination Survey (NHANES) prospective cohort research included 1980 MetS participants. To assess CysC levels and all-cause, CVD, and cancer mortality, fitted curves, Kaplan-Meier survival curves, Cox regression analysis, and receiver operating characteristic curves were performed.

RESULTS

During a mean follow-up of 15.3 ± 5.4 years, a total of 819 deaths occurred. The fitted and Kaplan-Meier survival curves revealed that greater CysC levels were linked to higher all-cause, CVD, and cancer mortality rates (P < .05). After adjusting for variables, CysC level was associated with all-cause, CVD, and cancer mortality at 1.63 (1.42-1.88), 1.53 (1.19-1.95), and 1.53 (1 ∼ 2.32), respectively (P < .05). Tertile models showed consistent results: high CysC Tertile participants showed higher risk of all-cause mortality (HR 1.87; 1.43-2.45), CVD mortality (HR 1.97, 1.15 ∼ 3.38), and cancer mortality (HR 1.72, 1.01 ∼ 2.91) compared to those in the lowest tertile (P < .05). Subgroup studies by sex and other characteristics confirmed the findings. CysC demonstrated the higher predictive efficacy across mortality outcomes, followed by eGFR, outperforming urea nitrogen, creatinine, uric acid, and C-reactive protein. CysC alone exhibited substantial predictive value for all-cause (AUC 0.773; P < .05) and CVD mortality (AUC 0.726; P < .05). Combining CysC with age enhanced predictive value for all-cause mortality to 0.861 and CVD mortality to 0.771 (P < .05).

CONCLUSION

MetS patients with elevated CysC levels have a higher risk of all-cause, CVD, and cancer death. CysC may predict MetS all-cause and CVD mortality.

Sex difference in the association between creatinine-to-cystatin C ratio and metabolic syndrome among Chinese adults

Background

Metabolic syndrome (MetS), characterized by central obesity, insulin resistance, dyslipidemia, and hypertension, affects 20-25% of the global population. The creatinine-to-cystatin C ratio (CCR) is an indicator of skeletal muscle mass. While CCR may play a role in MetS development, sex differences in these associations are not fully understood. Therefore, this study aimed to investigate how CCR levels are associated with MetS in a Chinese adult population, focusing on possible sex disparities.

Method

We conducted a retrospective cross-sectional analysis of 9,376 adults from Xiamen Chang Gung Hospital between 2014 to 2016. We examined the relationship between CCR and MetS, adjusting for cardiometabolic risk factors.

Results

The prevalence of MetS was 24.7% in males and 18.0% in females. Interestingly, we observed significant sex differences in the association between CCR quartiles and MetS. Females in the lowest CCR quartile had a significantly higher risk of MetS (odds ratio=1.84). Receiver operating characteristic curve analysis revealed acceptable diagnostic power of CCR for MetS in females (area under the curve=0.65) but not in males.

Conclusion

Our findings suggest that CCR is an independent risk factor for MetS in females, highlighting the importance of sex-specific assessments when evaluating MetS risk.

Medical comorbidities in bipolar disorder (BIPCOM): clinical validation of risk factors and biomarkers to improve prevention and treatment. Study protocol

BACKGROUND

BIPCOM aims to (1) identify medical comorbidities in people with bipolar disorder (BD); (2) examine risk factors and clinical profiles of Medical Comorbidities (MC) in this clinical group, with a special focus on Metabolic Syndrome (MetS); (3) develop a Clinical Support Tool (CST) for the personalized management of BD and medical comorbidities.

METHODS

The BIPCOM project aims to investigate MC, specifically MetS, in individuals with BD using various approaches. Initially, prevalence rates, characteristics, genetic and non-genetic risk factors, and the natural progression of MetS among individuals with BD will be assessed by analysing Nordic registers, biobanks, and existing patient datasets from 11 European recruiting centres across 5 countries. Subsequently, a clinical study involving 400 participants from these sites will be conducted to examine the clinical profiles and incidence of specific MetS risk factors over 1 year. Baseline assessments, 1-year follow-ups, biomarker analyses, and physical activity measurements with wearable biosensors, and focus groups will be performed. Using this comprehensive data, a CST will be developed to enhance the prevention, early detection, and personalized treatment of MC in BD, by incorporating clinical, biological, sex and genetic information. This protocol will highlight the study's methodology.

DISCUSSION

BIPCOM's data collection will pave the way for tailored treatment and prevention approaches for individuals with BD. This approach has the potential to generate significant healthcare savings by preventing complications, hospitalizations, and emergency visits related to comorbidities and cardiovascular risks in BD. BIPCOM's data collection will enhance BD patient care through personalized strategies, resulting in improved quality of life and reduced costly interventions. The findings of the study will contribute to a better understanding of the relationship between medical comorbidities and BD, enabling accurate prediction and effective management of MetS and cardiovascular diseases.

TRIAL REGISTRATION

ISRCTN68010602 at https://www.isrctn.com/ISRCTN68010602 . Registration date: 18/04/2023.

GFR estimated with creatinine rather than cystatin C is more reflective of the true risk of adverse outcomes with low GFR in kidney transplant recipients

BACKGROUND

Serum cystatin C-based estimated glomerular filtration rate (eGFRcys) generally associates with clinical outcomes better than serum creatinine-based eGFR (eGFRcr) despite similar precision in estimating measured GFR (mGFR). We sought to determine whether the risk of adverse outcomes with eGFRcr or eGFRcys was via GFR alone or also via non-GFR determinants among kidney transplant recipients.

METHODS

Consecutive adult kidney transplant recipients underwent a standardized GFR assessment during a routine follow-up clinic visit between 2011 and 2013. Patients were followed for graft failure or the composite outcome of cardiovascular (CV) events or mortality through 2020. The risk of these events by baseline mGFR, eGFRcr and eGFRcys was assessed unadjusted, adjusted for mGFR and adjusted for CV risk factors.

RESULTS

There were 1135 recipients with a mean baseline mGFR of 55.6, eGFRcr of 54.8 and eGFRcys of 46.8 ml/min/1.73 m2 and a median follow-up of 6 years. Each 10 ml/min/1.73 m2 decrease in mGFR, eGFRcr or eGFRcys associated with graft failure [hazard ratio (HR) 1.79, 1.68 and 2.07, respectively; P < .001 for all) and CV events or mortality outcome (HR 1.28, 1.19 and 1.43, respectively; P < .001 for all). After adjusting for mGFR, eGFRcys associated with graft failure (HR 1.57, P < .001) and CV events or mortality (HR 1.49, P < .001), but eGFRcr did not associate with either. After further adjusting for CV risk factors, risk of these outcomes with lower eGFRcys was attenuated.

CONCLUSION

eGFRcr better represents the true relationship between GFR and outcomes after kidney transplantation because it has less non-GFR residual association. Cystatin C is better interpreted as a nonspecific prognostic biomarker than is eGFR in the kidney transplant setting.

Serum Cystatin-C is linked to increased prevalence of diabetes and higher risk of mortality in diverse middle-aged and older adults

Objective

Type 2 Diabetes Mellitus (henceforth diabetes) affects roughly 35 million individuals in the US and is a major risk factor for cardiovascular and kidney disease. Serum Cystatin-C is used to monitor renal function and detect kidney damage. Recent research has focused on linking Cystatin-C to cardiovascular risk and disease, but most findings focus on small sample sizes and generalize poorly to diverse populations, thus limiting epidemiological inferences. The aim of this manuscript is to study the association between Cystatin-C, diabetes, and mortality and test for possible sex or racial/ethnic background modifications in these relationships.

Methods

We analyzed 8-years of biennial panel data from Health and Retirement Study participants 50-years and older who self-identified as White (unweighted N (uN) = 5,595), Black (uN = 867), or Latino (uN = 565) for a total of uN = 7,027 individuals. We modeled diabetes and death over 8-years as function of baseline Cystatin-C (log transformed) adjusting for covariates and tested modifications in associations by race/ethnic background and sex.

Results

Mean log Cystatin-C at visit 1 was 0.03±0.32 standard deviation. A 10% increase in Cystatin-C levels was associated with 13% increased relative risk of diabetes at baseline (11% and 9% by years 4 and 8). A 10% increase in Cystatin-C was highly associated with increased relative risk of death (28% and 31% by years 4 and 8). These associations were present even after adjusting for possible confounders and were not modified by sex or racial/ethnic background.

Conclusion

Despite differential risks for diabetes and mortality by racial/ethnic groups, Cystatin-C was equally predictive of these outcomes across groups. Cystatin-C dysregulations could be used as a risk indicator for diabetes and as a warning sign for accelerated risk of mortality.

Serum Cystatin C Levels Are Associated With Obesity in Adolescents Aged 14-17 Years

BACKGROUND

The association between serum cystatin C levels and obesity has not been fully explored in adolescents. This study aimed to explore the association between serum cystatin C levels and obesity in adolescents of different sexes.

METHODS

We conducted a cross-sectional study including 481 adolescents aged 14-17 years. Cystatin C level was measured by immunoassay. Health examinations data, biochemical parameters, and questionnaire information were collected. The restricted cubic spline model analyzed the association between cystatin C levels and obesity in boys and girls.

RESULTS

Boys exhibited significantly higher cystatin C levels than girls, with a mean level of 0.97 ± 0.10 mg/L in boys and 0.86 ± 0.09 mg/L in girls (P < 0.001). The restricted cubic spline model suggested that low or high cystatin C levels were associated with an increased risk of obesity in boys, whereas only higher cystatin C levels were associated with an increased risk of obesity in girls.

CONCLUSIONS

A U-shaped correlation was observed between serum cystatin C levels and the risk of obesity in boys. However, in girls, the risk of obesity showed a trend of initially increase and then decrease with increasing cystatin C levels. Longitudinal studies should be conducted to further investigate the diagnostic potential of cystatin C in the progression of early obesity in adolescents of different sexes.

Diagnostic Power of Circulatory Metabolic Biomarkers as Metabolic Syndrome Risk Predictors in Community-Dwelling Older Adults in Northwest of England (A Feasibility Study)

Background: Metabolic Syndrome (MetS) is a cluster of risk factors for diabetes and cardiovascular diseases with pathophysiology strongly linked to aging. A range of circulatory metabolic biomarkers such as inflammatory adipokines have been associated with MetS; however, the diagnostic power of these markers as MetS risk correlates in elderly has yet to be elucidated. This cross-sectional study investigated the diagnostic power of circulatory metabolic biomarkers as MetS risk correlates in older adults. Methods: Hundred community dwelling older adults (mean age: 68.7 years) were recruited in a study, where their blood pressure, body composition and Pulse Wave Velocity (PWV) were measured; and their fasting capillary and venous blood were collected. The components of the MetS; and the serum concentrations of Interleukin-6 (IL-6), Tumor Necrosis Factor-α (TNF-α), Plasminogen Activator Inhibitor-I (PAI-I), Leptin, Adiponectin, Resistin, Cystatin-C, C-Reactive Protein (CRP), insulin and ferritin were measured within the laboratory, and the HOMA1-IR and Atherogenic Index of Plasma (AIP) were calculated. Results: Apart from other markers which were related with some cardiometabolic (CM) risk, after Bonferroni correction insulin had significant association with all components of Mets and AIP. These associations also remained significant in multivariate regression. The multivariate odds ratio (OR with 95% confidence interval (CI)) showed a statistically significant association between IL-6 (OR: 1.32 (1.06–1.64)), TNF-α (OR: 1.37 (1.02–1.84)), Resistin (OR: 1.27 (1.04–1.54)) and CRP (OR: 1.29 (1.09–1.54)) with MetS risk; however, these associations were not found when the model was adjusted for age, dietary intake and adiposity. In unadjusted models, insulin was consistently statistically associated with at least two CM risk factors (OR: 1.33 (1.16–1.53)) and MetS risk (OR: 1.24 (1.12–1.37)) and in adjusted models it was found to be associated with at least two CM risk factors and MetS risk (OR: 1.87 (1.24–2.83) and OR: 1.25 (1.09–1.43)) respectively. Area under curve (AUC) for receiver operating characteristics (ROC) demonstrated a good discriminatory diagnostics power of insulin with AUC: 0.775 (0.683–0.866) and 0.785 by cross validation and bootstrapping samples for at least two CM risk factors and AUC: 0.773 (0.653–0.893) and 0.783 by cross validation and bootstrapping samples for MetS risk. This was superior to all other AUC reported from the ROC analysis of other biomarkers. Area under precision-recall curve for insulin was also superior to all other markers (0.839 and 0.586 for at least two CM risk factors and MetS, respectively). Conclusion: Fasting serum insulin concentration was statistically linked with MetS and its risk, and this link is stronger than all other biomarkers. Our ROC analysis confirmed the discriminatory diagnostic power of insulin as CM and MetS risk correlate in older adults.

Review of proteomics approach to eye diseases affecting the anterior segment

Visual impairment and blindness is a major health burden worldwide, and major ocular diseases causing visual impairment pertain to the anterior segment of the eye. Anterior segment ocular diseases are common, yet complex entities. Although many treatment options and surgical techniques are available for these ailments, the underlying cause and pathogenesis is still unclear. Finding ways to fundamentally treat these patients and rectify the underlying dysregulations leading to the disease may help cure patients completely without major complications. Proteomics approaches are a novel way to distinguish dysregulated proteins in a variety of biological tissues in a hypothesis-free manner, thus helping to find the responsible pathways leading to a certain disease. The aim of the current study is to review the available knowledge in scientific literature regarding the proteomics studies done on anterior segment eye diseases and suggest potential clinical implications to exploit the results of these studies. SIGNIFICANCE: Anterior segment ocular diseases are responsible for a major proportion of visual impairment and blindness worldwide. Although ophthalmologists have several treatment options that can alleviate or control the progression of these diseases, no definite cure is available for most of them. Moreover, because these diseases are progressive, prompt diagnosis is of utmost important. Proteomics studies enable us to identify and quantify the dysregulated proteins in a biological specimen in a hypothesis-free manner. Understanding the dysregulated protein pathways shines a light on the pathogenesis of the disease. Moreover, these dysregulated proteins may act as biomarkers to help in diagnosis and treatment follow-up. Hence, in this article we sought out to review the available scientific literature regarding the proteomics studies of anterior segment ocular diseases and to identify potential applications of proteomic studies in clinic.

Serum Cystatin C and Arterial Stiffness in Middle-Aged and Elderly Adults without Chronic Kidney Disease: A Population-Based Study

BACKGROUND Cystatin C is a protease inhibitor that is increased in the serum of patients with chronic kidney disease (CKD) and is associated with an increased risk of developing cardiovascular disease (CVD). This study aimed to evaluate the association between serum levels of cystatin C and arterial stiffness, associated with dyslipidemia, obesity, and increased pulse pressure, in middle-aged and elderly individuals without CKD in a population in China. MATERIAL AND METHODS A cross-sectional population-based study included 1,138 patients aged ≥40 years without CKD, defined as an estimated glomerular filtration rate measured by serum creatinine (eGFRSCr) ≥60 ml/min/1.73 m². Study participants provided clinical details, including height and weight, and blood samples for serum measurements of cystatin C and lipid profiles and completed a clinical questionnaire. Pulse pressure was calculated as the mean systolic pressure (SBP) minus the diastolic pressure (DBP). Data underwent multivariate logistic regression analysis. RESULTS An increase in serum levels of cystatin C was associated with an increased risk of arterial stiffness. Each standard deviation in the increase of cystatin C resulted in a 22% increased risk of dyslipidemia, a 27% increased risk of obesity, and a 24% increased risk of increased pulse pressure, after adjusting for confounders. These associations were further confirmed in a sensitivity analysis by excluding participants with hypertension, diabetes, and patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). CONCLUSIONS In middle-aged and elderly individuals without CKD, arterial stiffness determined by obesity, dyslipidemia and increased pulse pressure, was significantly associated with increased serum levels of cystatin C.

Genetic and Environmental Influences on the Correlations between Traits of Metabolic Syndrome and CKD

BACKGROUND AND OBJECTIVES

Metabolic syndrome is a cluster of risk factors associated with CKD. By studying the genetic and environmental influences on how traits of metabolic syndrome correlate with CKD, the understanding of the etiological relationships can be improved.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

From the population-based TwinGene project within the Swedish Twin Registry, 4721 complete twin pairs (9442 European ancestry participants) were included in this cross-sectional twin study. Metabolic syndrome-related continuous traits were measured, and the binary components as well as the status of metabolic syndrome were defined according to the National Cholesterol Education Program-Adult Treatment Panel III. The eGFR was calculated by cystatin C-based equations from the CKD epidemiology collaboration group, and CKD was defined by eGFR<60 ml/min per 1.73 m². Genetic and environmental contributions to the correlations between traits of metabolic syndrome and CKD were estimated by using twin-based bivariate structural equation models.

RESULTS

The correlation between metabolic syndrome and eGFR-defined CKD was 0.16 (95% confidence interval [95% CI], 0.12 to 0.20), out of which 51% (95% CI, 12% to 90%) was explained by genes, whereas 15% (95% CI, 0% to 42%) and 34% (95% CI, 16% to 52%) was explained by the shared and nonshared environment, respectively. The genetic and environmental correlations between metabolic syndrome and CKD were 0.29 (95% CI, 0.07 to 0.51) and 0.27 (95% CI, 0.13 to 0.41), respectively. For the correlation between abdominal obesity and eGFR, 69% (95% CI, 10% to 100%) was explained by genes and 23% (95% CI, 5% to 41%) was explained by environment. The genetic correlation between abdominal obesity and eGFR was -0.30 (95% CI, -0.54 to -0.06), whereas the environmental correlation was -0.14 (95% CI, -0.22 to -0.06).

CONCLUSIONS

Both genes and environment contribute to the correlation between metabolic syndrome and eGFR-defined CKD. The genetic contribution is particularly important to the correlation between abdominal obesity and eGFR.

Association of Cystatin C with Metabolic Syndrome and Its Prognostic Performance in Non-ST-Segment Elevation Acute Coronary Syndrome with Preserved Renal Function

OBJECTIVE

The underlying mechanisms by which cystatin C affects cardiovascular disease (CVD) are not very clear. Metabolic syndrome (MetS) is a cluster of risk factors that increase the risk of CVD. Here, we aimed to investigate the association of cystatin C with metabolic syndrome and cardiovascular outcomes in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) with preserved renal function.

METHODS

In total, 422 NSTE-ACS patients with preserved renal function were enrolled to examine the association of cystatin C with MetS. MetS was defined based on the NCEP-ATP-III guidelines. Major adverse cardiovascular events (MACEs) were also evaluated, which included cardiac death, nonfatal myocardial infarction (MI), target vessel revascularization (TVR), heart failure, and nonfatal stroke. All patients underwent a 12-month follow-up for MACEs after admission.

RESULTS

Cystatin C was significantly correlated with metabolic risk factors and inflammation markers. The prevalence of MetS and MACEs correlated with cystatin C levels. Cystatin C showed a strong diagnostic performance for cardiovascular risk factors and outcomes in ROC analysis. After adjustment for multiple risk factors, cystatin C level was independently associated with MetS (OR 2.299, 95% CI 1.251-4.225, and P = 0.007). During a 12-month follow-up, the patients with high cystatin C level and MetS had higher incidence of MACEs (Log-rank = 24.586, P < 0.001) and cardiac death (Log-rank = 9.890, P = 0.020) compared to the others. Multivariate Cox analysis indicated that cystatin C level was an independent predictor of MACEs (HR 2.609, 95% CI 1.295-5.257, and P = 0.007).

CONCLUSION

Cystatin C may be an independent predictor of metabolic syndrome and therefore valuable for management of NSTE-ACS patients. Further multicenter, large-scale studies are required to assess the implication of these results.

Biomarkers of Atrial Fibrillation in Metabolic Syndrome

Whether the increased atrial fibrillation (AF) risk in metabolic syndrome (MetS) patients is due to the syndrome as a whole or simply the sum of the risks of its individual component parts is still obscure. These two clinical entities share many pathophysiological links and thus distinction between a casual observation and a significant association is difficult. Biomarkers associated with pathogenesis of AF in the context of MetS have the ability to refine future risk prediction. In the present review we identify circulating substances that could be regarded as potential biomarkers for prediction of incident AF, or of cardiovascular events in the setting of AF in patients with MetS. Cardiac myocyte injury and stress markers (troponin and natriuretic peptides), markers of renal function (glomeral filtration rate, cystatin-C), and inflammation markers/mediators (interleukin- 6, CRP) are promising biomarkers of patients with AF and MetS.

Relationship of High Circulating Cystatin C to Biochemical Markers of Bone Turnover and Bone Mineral Density in Elderly Males with a Chronic Heart Failure

Background

The aim of the study was to investigate the association of Cystatin C (CysC) to biochemical markers of bone turnover and bone mass, and to evaluate its prognostic significance in elderly males with chronic heart failure (CHF).

Methods

A prospective cohort study was executed on sixtyeight males (mean age 68±7 years) with mild to moderate CHF, together with 19 of corresponding age- and body mass index-matched healthy individuals who underwent cardio vascular, bone mineral density (BMD), and body com position assessment. Biochemical assessment of all subjects included NT-pro-BNP, parathyroid hormone (PTH), 25-hydroxy vitamin D (25(OH)D), CysC, and biochemical markers of bone turnover including osteocalcin (OC), alkaline phosphatase (ALP), β-CrossLaps (β-CTx), osteoprotegerin (OPG), and receptor activator of nuclear factor κB ligand (RANKL).

Results

Serum CysC was significantly increased in males with CHF in comparison to healthy control ones. A significant positive association was found between CysC levels and OC in males with CHF, while OC and β-CTx increased in increasing CysC tertiles. In multivariate regression analysis, OC and smoking were a significant determinant of CysC in males with CHF. Level of CysC was found to be positively associated with an increased fatal risk in males with CHF.

Conclusions

Serum osteocalcin is an independent predictor of CysC level in elderly males with CHF. Higher CysC level showed a negative relation to survival and bone loss in males with CHF. Further research is needed to confirm the potential role of CysC in the crosstalk between heart, kidney, bone, and energy metabolism in CHF.

Retinol-binding protein 4 better correlates with metabolic syndrome than cystatin C

Background

Retinol-binding protein 4 (RBP4) and cystatin C are regarded as novel metabolic risk markers. Therefore, we aimed to examine which one of these biomarkers better correlates with metabolic syndrome (MetS) in a cohort of postmenopausal women.

Methods

A total of 129 postmenopausal women (among which 62 women had MetS) were recruited in this cross-sectional study. MetS was diagnosed according to the International Diabetes Federation criteria.

Results

Cystatin C and RBP4 levels were significantly higher in women with MetS, compared to those without MetS (p=0.011 vs. p<0.001, respectively). A significant difference in the proportion of women with and without MetS across cystatin C and RBP4 quartiles was observed (χ2=5.1, p=0.025, and χ2=11.1, p=0.001, respectively). Logistic regression analysis revealed a borderline significant relationship between cystatin C and MetS (p=0.066), but this significance disappeared after adjustment for age, inflammation level and duration of menopause (p=0.221). On the contrary, a significant relationship between RBP4 and MetS was observed not only without adjustment (p=0.009), but also even after adjustment for age, inflammation level and duration of menopause (p=0.006).

Conclusions

RBP4 better correlates with MetS than cystatin C in postmenopausal women.

Cystatin C in adipose tissue and stimulation of its production by growth hormone and triiodothyronine in 3T3-L1 cells

Cystatin C (CysC) is a marker for estimation of glomerular filtration rate (GFR). CysC levels may depend not only on clearance/GFR but possibly also on changes in production. Our studies on tissue distribution of CysC protein in mice showed that adipose tissue expresses significant amounts of CysC, suggesting that adipocytes could contribute to circulating CysC levels in vivo. As growth hormone (GH) and triiodothyronine (T₃) increase both GFR and CysC (increased in acromegaly and hyperthyroidism) in vivo, we studied whether they could increase CysC production in 3T3-L1 adipocytes in vitro. CysC accumulated in culture media of 3T3-L1 adipocytes in a time-dependent fashion. GH and T₃ both (10 nmol/l) increased accumulation of CysC, to 373 ± 14 and 422 ± 20, respectively, vs 298 ± 10 ng per well over 4 days in controls. Thus, GH and T₃ enhance the production of CysC by adipocytes in vitro.

Aberrant cystatin-C expression in blood from patients with breast cancer is a suitable marker for monitoring tumor burden

The present study was performed to evaluate the efficacy of circulating cystatin-C as a tumor monitoring biomarker at different clinical time points in patients with breast cancer over a long-term follow-up period. In addition, the secretory rate of circulating cystatin-C from cancer tissue was investigated by comparing the blood and tissue expression levels of cystatin-C. Blood samples from healthy volunteers (40 males and 40 females) were obtained at yearly health examinations if laboratory and imaging abnormalities were not detected. Blood samples from 34 patients with breast cancer were obtained at 205 different time points of clinical progression. Blood levels of cystatin-C were measured using ELISA and the tissue levels were measured using immunohistochemistry. No age-associated effect was observed in male and female blood cystatin-C levels. The positivity rate was 46% in patients (38/83) and 40% in samples collected at different time points (82/205). Blood cystatin-C levels were lowest following surgery compared with patients with systemic metastasis (P<0.001). The sensitivity, specificity and accuracy rates of ELISA were 53.6, 63.6 and 53.9%, respectively. The concordance rate between blood and tissue expression was 38%. The main reason for discordance between tissue and serum expression of cytostatin-C came from low serum positivity in samples showing tissue cytostatin-C (3/11, 27%). The specificity between cytostatin-C and CA-125 was highest in tumor absence state. In conclusion, elevated blood levels of cystatin-C were observed in 40% of breast cancer cases and were tumor-volume dependent. However, the concordance rate between tissue and blood was quite low, suggesting tumor heterogeneity of cystatin-C expression or co-acting pathway activation, such as cathepsin D. As one-third of breast cancer tissues express cystatin-C without cancer antigen 15-3 elevation, cystatin-C may represent a good tumor-monitoring marker in breast cancer.

Higher Levels of Cystatin C in HIV/AIDS Patients with Metabolic Syndrome

Data about Cystatin-C levels in HIV-infected patients with metabolic syndrome (MetS) are still limited. Therefore, the aim of this study was to evaluate the possible correlations of serum levels of Cystatin-C in HIV/AIDS patients treated with combined antiretroviral therapy (cART) with or without MetS. This cross-sectional study included 89 HIV/AIDS Caucasian patients receiving cART at the HIV/AIDS Centre Belgrade, Serbia, divided into two groups according to the presence of MetS. Cystatin-C and other biochemical parameters were measured using Cytokine-Array-I, Metabolic-Array-I and Metabolic-Array-II, at the Department of Clinical Biochemistry, Royal Free Hospital and University College London, UK. A linear regression model was performed to evaluate which clinical and laboratory variables had an independent effect on Cystatin-C levels in HIV/AIDS patients. There were 33 (37%) patients with MetS and 56 (63%) without MetS. Patients with and without MetS were homogenous for age, duration of cART, number of cART combinations and CD4⁺ T cell count. Statistically increased Cystatin-C levels were observed in HIV/AIDS patients with MetS (p = 0.017), when compared to patients without MetS. Data showed a positive correlation of Cystatin-C and C-reactive protein (r = 0.349, p = 0.001). Using linear regression modelling, significant correlations were obtained between Cystatin-C and MetS in univariate analysis (p < 0.001). Cystatin-C levels were significantly higher in HIV/AIDS patients with MetS versus without MetS. Early assessment of MetS using Cystatin-C as a marker may ultimately help increase the lifespan of HIV/AIDS patients, as these patients appear to be at high risk of cardiovascular diseases.

CSTB Downregulation Promotes Cell Proliferation and Migration and Suppresses Apoptosis in Gastric Cancer SGC-7901 Cell Line

This study aimed to investigate the pivotal role of cystatin B (CSTB) in the development of gastric cancer and to explore its possible regulatory mechanism. Human gastric cancer SGC-7901 cells as a model in vitro were transfected with plasmid PCDNA3.1-CSTB and siRNA-CSTB using Lipofectamine 2000. Quantitative real-time PCR (qRT-PCR) and Western blotting were performed to determine the relative expression of CSTB and PI3K/Akt/mTOR pathway-related protein. Moreover, MTT assay, Transwell assay, and flow cytometry were used to assess cell proliferation, migration, and apoptosis, respectively. The results showed that CSTB was significantly downregulated in SGC-7901 cells compared with gastric epithelial cells. CSTB was successfully overexpressed and suppressed after cells were transfected with pc-CSTB and si-CSTB, respectively. Moreover, cell viability and migration were significantly decreased after being transfected with pc-CSTB when compared with the control group, while being obviously increased after transfection with si-CSTB. However, cell apoptosis was significantly induced after being transfected with pc-CSTB, while being obviously suppressed after transfection with si-CSTB. Besides, the expression levels of p-PI3K, p-Akt, and p-mTOR proteins were all significantly decreased in the pc-CSTB transfection group when compared with the control group, while being increased in the si-CSTB transfection group. Our findings suggest that CSTB downregulation may promote the development of gastric cancer by affecting cell proliferation and migration, and the PI3K/Akt/mTOR signaling pathway was activated in this process. CSTB may serve as a potential therapeutic target for gastric cancer.

Association of body mass index, waist circumference, and metabolic syndrome with serum cystatin C in a Chinese population

BACKGROUND

The aim of the study was to evaluate the association of body mass index (BMI), waist circumference (WC), and metabolic syndrome (MetS) with serum cystatin C (CysC) in a Chinese population.

METHODS

The population was composed of 5866 subjects. MetS was diagnosed using the American Heart Association/National Heart, Lung, and Blood Institute 2005 (NCEP-R) criteria. Covariates were analyzed using logistic regression and Spearman partial correlation.

RESULTS

In this population, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), high sensitivity C-reactive protein (hs-CRP), BMI, WC, systolic blood pressure (SBP), diastolic blood pressure (DBP), serum creatinine (Scr), and CysC were significantly higher, and HDL-C and the estimated glomerular filtration rate (Chronic Kidney Disease Epidemiology Collaboration) (eGFRCKD-EPI) were significantly lower in the MetS than in the non-MetS group. TG, LDL-C, FPG, hs-CRP, BMI, WC, SBP, DBP, and Scr were significantly higher, and HDL-C and eGFRCKD-EPI were significantly lower in the 4th quartile than in the 1st quartile of CysC. Logistic regression analysis showed that sex, age, hs-CRP, and CysC were independently associated with the presence of MetS (OR = 3.732, 1.028, 1.051, and 3.334, respectively; P < 0.05). No significant association between the presence of MetS and either Scr or eGFRCKD-EPI was observed. After adjustment for age and sex, BMI, WC, hs-CRP, and Scr were all positively correlated, whereas eGFRCKD-EPI was negatively correlated with CysC (r = 0.029, 0.061, 0.189, 0.227, and -0.210, respectively; P < 0.05).

CONCLUSION

The present study revealed that the CysC was more closely associated with the presence of MetS, as compared Scr or eGFRCKD-EPI. CysC was positively correlated with BMI, and more strongly, positively correlated with WC and inflammation.

Cystatin C is a useful predictor of early neurological deterioration following ischaemic stroke in elderly patients with normal renal function

Introduction

Cystatin C has been suggested as a sensitive marker of renal function. A high level of cystatin C is related to cardiovascular disease and stroke in elderly patients. We investigated the relationship between levels of cystatin C and early neurological deterioration with acute ischaemic stroke in elderly patients without chronic kidney disease.

Patients and methods

We evaluated a total of 771 elderly patients (mean age, 72.2; male, 59.0%) without chronic kidney disease who were admitted following acute ischaemic stroke between March 2010 and January 2015. The patients were divided into four groups based on the quartiles of serum cystatin C values. Early neurological deterioration was defined as an increase of ≥2 points from the baseline National Institutes of Health Stroke Scale score during the 7 days following onset. We compared the clinical characteristics and cystatin C concentrations between patients with and without early neurological deterioration.

Results

Eighty-six patients (11.2%) experienced early neurological deterioration. The percentage values of the higher (third and fourth) quartiles were significantly higher in the early neurological deterioration group (30.2% vs. 24.4% and 34.9% vs. 23.8%, P = 0.002). After adjustment for covariates, higher cystatin C levels were independently associated with a higher risk of early neurological deterioration: odds ratio (95% confidence interval) for second quartile 1.59 (0.70-3.58), third quartile 2.75 (1.25-6.04), fourth quartile 3.12 (1.36-7.16); P for trend 0.026.

Discussion and conclusions

This study demonstrated that cystatin C concentrations in elderly patients without chronic kidney disease were associated with early neurological deterioration following acute stroke. This suggests that cystatin C level could be a useful predictor for early neurological deterioration following acute stroke.

Cystatin C, a novel cardiometabolic risk marker in women with polycystic ovary syndrome

OBJECTIVE

To investigate the impact of urinary albumin excretion (UAE) and cystatin C on the metabolic components of polycystic ovary syndrome (PCOS).

METHODS

Seventy-five women with PCOS were divided into two groups according to metabolic syndrome as MetS + and MetS-. Clinical, metabolic and renal parameters were compared between the groups. Correlation analyses were performed between cystatin C, microalbuminuria and clinical and metabolic parameters in women with PCOS.

RESULTS

Waist/hip ratio (WHR), body mass index, LDL cholesterol, triglyceride, total cholesterol, cystatin C, UAE were significantly higher in the MetS + group compared with the MetS - one. HDL cholesterol was significantly higher in the MetS - group than the MetS + one. The UAE positively correlates with LDL cholesterol, triglyceride and total cholesterol levels. Cystatin C positively correlates with UAE, WHR, LDL cholesterol, triglyceride, total cholesterol levels.

CONCLUSIONS

Evaluating UAE and cystatin C may be important for the detection of target subjects at high risk for future metabolic syndrome and cardiovascular disease.

Cystatin C and Risk of Diabetes and the Metabolic Syndrome - Biomarker and Genotype Association Analyses

Background

We recently reported a relationship between plasma levels of cystatin C and incidence of the metabolic syndrome (MetS) among the first 2,369 subjects who participated in the re-examination study of the population-based Malmö and Diet Cancer Cardiovascular cohort (MDC-CC-re-exam). In this study we aimed to replicate these results and also investigate if cystatin C was causally associated with MetS and diabetes.

Methods

We estimated the effect size of the strongest GWAS derived cystatin C SNP (major allele of rs13038305) on plasma cystatin C in the now completed MDC-CC-re-exam (n = 3,734) and thereafter examined the association between plasma cystatin C (403 cases of diabetes and 2665 controls) as well as rs13038305 (235 cases and 2425 controls) with incident diabetes. The association of rs13038305 and incident MetS (511 cases of MetS and 1980 controls) was similarly investigated in the whole MDC-CC-re-exam. We also attempted to replicate our previously shown association of cystatin C with incident MetS in subjects from the MDC-CC-re-exam (147 cases and 711 controls) that were not included in our previous report.

Results

In the entire MDC-CC-re-exam, each copy of the major allele of rs13038305 was associated with approximately 0.30 standard deviation (SD) higher plasma concentration of cystatin C (β = 0.33, p = 4.2E^-28) in age and sex adjusted analysis. Cystatin C in plasma was not associated with incident diabetes after adjustment for known diabetes risk factors (OR per 1 SD increment 0.99 (0.86–1.13), p = 0.842). In the replication cohort of MDC-CC-re-exam, the OR (95% CI) for incident MetS in subjects belonging to quartiles 1, 2, 3 and 4 of plasma cystatin C levels was 1.00 (reference), 1.21 (0.70–2.07), 1.62 (0.95–2.78) and 1.72 (1.01–2.93) (p_trend = 0.026) in age and sex adjusted analysis. In the entire MDC-CC-re-exam the odds ratio for incident MetS and diabetes per copy of the major rs13038305 allele was 1.13, (0.95–1.34), p = 0.160 and 1.07, 95% CI 0.89–1.30, p = 0.478, respectively.

Conclusion

We were able to replicate our previously shown association between high levels of cystatin C and increased risk of future development of MetS. However, a causal involvement of cystatin C in the etiology of MetS or diabetes seems unlikely since genetic elevation of plasma cystatin C was not significantly related to incidence of these diseases.

Assessment of kidney dysfunction with cystatin C- and creatinine-based estimated glomerular filtration rate and predicting type 2 diabetes: Toranomon Hospital Health Management Center Study 21

OBJECTIVE

Whether early stages of kidney dysfunction assessed by the estimated glomerular filtration rate from cystatin C measurements (eGFRCysC) rather than from creatinine measurements (eGFRCr) would more precisely reflect the risk of developing type 2 diabetes (T2D) has not been clarified. We compared the risk of developing T2D associated with renal dysfunction indicated by eGFRCysC or eGFRCr measurements.

METHODS

Studied were 2131 Japanese individuals without diabetes. Hazard ratios (HRs) for the development of T2D over 3-5 y were calculated across categories of eGFRCysC and eGFRCr, respectively.

RESULTS

Reduced levels of eGFRCysC were associated with a step-wise increase in the cumulative incidence rate of T2D (p=0.007). In comparison with the eGFRCysC >85th percentile group (≥ 117.4 ml/min/1.73 m(2)), the lowest group, which was the eGFRCysC <15th percentile group (<86.2 ml/min/1.73 m(2)), had an adjusted HR of 2.30 (95% CI 1.13, 4.68) for T2D. Compared with the eGFRCr >85th percentile group, the lowest eGFRCr group (<15th percentile) had an HR of 1.19 (0.63, 2.24) for T2D. However, individuals with eGFRCr <60 ml/min/1.73 m(2) had a significantly increased risk of T2D. Clustering of both low eGFRCysC and low eGFRCr further elevated the HR for T2D compared with the presence of either.

CONCLUSIONS

Although eGFRCr in ranges indicating chronic kidney disease reflected an elevated risk of developing diabetes, earlier stages of kidney dysfunction indicated by reduced eGFRCysC, which could not be captured by reduced eGFRCr, would be a marker for an elevated risk of developing T2D.

Relationship between cystatin C and metabolic syndrome among Chinese premenopausal and postmenopausal women without recognized chronic kidney disease

OBJECTIVE

Although studies have shown that elevated cystatin C (Cys-C) levels are associated with the risk of metabolic syndrome (MetS) in the general population, few studies have examined the relationship between serum Cys-C levels and MetS, stratified by menopause status, among women in China. Therefore, we conducted this study to assess the relationship between Cys-C levels and MetS in Chinese premenopausal and postmenopausal women.

METHODS

We performed a cross-sectional analysis of the baseline data of 1,428 Chinese community-dwelling women who participated in the annual health checkup. MetS was defined by the updated National Cholesterol Education Program/Adult Treatment Panel III criteria. Binary logistic regression analysis was performed to estimate the association between Cys-C levels and MetS. One-way analysis of variance, followed by posttest for linear trends, was performed to evaluate the relationships between Cys-C levels and the number of MetS components. Ordinal regression analysis was used to determine whether menopause status and MetS components contribute to elevated levels of Cys-C.

RESULTS

The mean level of Cys-C was significantly higher in women with MetS than in those without MetS among both premenopausal and postmenopausal women, showing a progressive increase (P for trend < 0.001) in parallel with the progressive increment in the number of MetS components in all women. Higher Cys-C levels were found to be associated with the presence of MetS after adjusting for age, body mass index, and estimated glomerular filtration rate in all women. The higher odds ratio changed little, even after further adjustment for serum blood nitrogen, total cholesterol, low-density lipoprotein cholesterol, drinking status, and smoking status. Elevated Cys-C level was significantly associated with postmenopause status (P = 0.007), increased waist circumference (P = 0.006), and elevated blood pressure (P = 0.025).

CONCLUSIONS

Higher serum Cys-C levels are positively and independently associated with the presence of MetS in Chinese premenopausal and postmenopausal women. Elevated Cys-C levels are significantly associated with postmenopause status.

High levels of cathepsin D and cystatin B are associated with increased risk of coronary events

Objective

The majority of acute coronary syndromes are caused by plaque ruptures. Proteases secreted by macrophages play an important role in plaque ruptures by degrading extracellular matrix proteins in the fibrous cap. Matrix metalloproteinases have been shown to be markers for cardiovascular disease whereas the members of the cathepsin protease family are less studied.

Methods

Cathepsin D, cathepsin L and cystatin B were measured in plasma at baseline from 384 individuals who developed coronary events (CEs), and from 409 age-matched and sex-matched controls from the Malmö Diet and Cancer cardiovascular cohort.

Results

Cathepsin D (180 (142–238) vs 163 (128–210), p<0.001), cathepsin L (55 (44–73) vs 52 (43–67), p<0.05) and cystatin B levels (45 (36–57) vs 42 (33–52), p<0.001) were significantly increased in CE cases compared to controls. In addition, increased cathepsin D (220 (165–313) vs 167 (133–211), p<0.001), cathepsin L (61 (46–80) vs 53 (43–68), p<0.05) and cystatin B (46 (38–58) vs 43 (34–54), p<0.05) were associated with prevalent diabetes. Furthermore, cathepsin D and cystatin B were increased in smokers. The HRs for incident CE comparing the highest to the lowest tertile(s) of cathepsin D and cystatin B were 1.34 (95% CI 1.02 to 1.75) and 1.26 (95% CI 1.01 to 1.57), respectively, after adjusting for age, sex, low-density lipoprotein/high-density lipoprotein ratio, triglycerides, body mass index, hypertension and glucose, but these associations did not remain significant after further addition of smoking to the model. In addition, cathepsin D was increased in incident CE cases among smokers after adjusting for cardiovascular risk factors.

Conclusions

The associations of cathepsin D and cystatin B with future CE provide clinical support for a role of these factors in cardiovascular disease, which for cathepsin D may be of particular importance for smokers.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

Cystatin C Is Not Causally Related to Coronary Artery Disease

BACKGROUND

Strong and independent associations between plasma concentration of cystatin C and risk of cardiovascular disease (CVD) suggests causal involvement of cystatin C.

AIM

The aim of our study was to assess whether there is a causal relationship between plasma concentration of cystatin C and risk of coronary artery disease (CAD) using a Mendelian Randomization approach.

METHODS

We estimated the strength of association of plasma cystatin C on CAD risk and the strength of association of the strongest GWAS derived cystatin C SNP (rs13038305) on plasma cystatin C in the population-based Malmö Diet and Cancer Study (MDC) and thereafter the association between rs13038305 and CAD in the MDC (3200 cases of CAD and 24418 controls) and CARDIOGRAM (22233 cases of CAD and 64762 controls).

RESULTS

Each standard deviation (SD) increment of plasma cystatin C was associated with increased risk of CAD (OR = 1.20, 95% CI 1.07-1.34) after full adjustment. Each copy of the major allele of rs13038305 was associated with 0.34 SD higher plasma concentration of cystatin C (P<1 x 10-35), resulting in a power of >98% to detect a significant relationship between rs13038305 and CAD in MDC and CARDIOGRAM pooled. The odds ratio for CAD (per copy of the major rs13038305 allele) was 1.00 (0.94-1.07); P = 0.92 in MDC, 0.99 (0.96-1.03); P = 0.84 in CARDIOGRAM and 1.00 (0.97-1.03); P = 0.83 in MDC and CARDIOGRAM pooled.

CONCLUSION

Genetic elevation of plasma cystatin C is not related to altered risk of CAD, suggesting that there is no causal relationship between plasma cystatin C and CAD. Rather, the association between cystatin C and CAD appears to be due to the association of eGFR and CAD.

Clinical analysis of the relationship between cystatin C and metabolic syndrome in the elderly

OBJECTIVE

Studies have shown that both cystatin C and metabolic syndrome (MetS) are associated with inflammation. We set out to investigate the correlation between serum cystatin C levels and MetS in the elderly.

METHODS

This prospective study was conducted in 380 elderly individuals, including 135 patients with MetS, 142 patients with metabolic disturbance (MetD), and 103 healthy elderly individuals (control group). Waist-hip ratio, waist circumference, waist-height ratio, body mass index (BMI), fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), high-density lipoprotein (HDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure and cystatin C were measured and their mutual relations were analyzed.

RESULTS

The higher the MetS scores, the higher the serum cystatin C concentration in these patients. Serum cystatin C concentration was closely related to waist-hip ratio, waist circumference, waist-height ratio, BMI, TG, FPG, and blood pressure, not related to LDL-C levels, and negatively correlated with HDL-C levels. Logistic regression analysis indicated that cystatin C, waist-height ratio, waist circumference, FPG, TG, SBP and pulse pressure were significantly associated with MetS (OR between cystatin C and MetS 2.164, 95% CI 1.136-8.259).

CONCLUSION

Cystatin C was significantly associated with MetS in the elderly. As MetS scores rose, serum cystatin C levels increased.

Association of cystatin C with measures of obesity and its impact on cardiovascular events among healthy US adults

BACKGROUND

This study sought to explore the relationship between cystatin C (CysC) and anthropometric measures of obesity and the influence of this association on mortality [cardiovascular disease (CVD), coronary heart disease, and all-cause] in a nationally representative population free of CVD, diabetes mellitus, and macroalbuminuria (MA).

METHODS

The study cohort included 4577 adult participants of the Third National Health and Nutrition Examination Survey (NHANES). Spearman correlation analysis was performed to ascertain the association between various anthropometric measures and CysC. Formal statistical analyses of the interaction term between anthropometric measures and CysC for outcomes were performed followed by stratified multivariate Cox proportional hazard analyses.

RESULTS

A moderate degree of association was seen between CysC and measures of visceral adiposity as represented by waist-to-height ratio (WHR) and waist circumference (WC) and only a weak association between CysC and body mass index (BMI). CysC was predictive of all study outcomes in individuals with normal anthropometric measurements only.

CONCLUSIONS

CysC correlated better with measures of visceral adiposity (WC and WHR) compared to BMI and appears to be a better predictor of adverse cardiovascular outcomes among those with anthropometric measures not suggestive of obesity compared to those with abnormal measures of anthropometry.

Cystatin C as a predictor of mortality and cardiovascular events in a population with chronic kidney disease

Background. We examine whether cystatin C, a surrogate marker of renal function, could identify patients with chronic kidney disease (CKD) with an increased risk of renal disease progression, death, or cardiovascular events. Methods. Data were obtained for 180 patients, with a diagnosis of chronic renal failure based on serum creatinine estimated glomerular filtration rate (eGFRcreat) <90 mL/min/1.73 m(2). This population was grouped in tertiles according to cystatin C and creatinine values at baseline. Cardiovascular events and overall mortality were estimated for each tertile. Predictors of overall mortality and for the development of renal disease progression were analyzed. Results. The median age was 75 years (interquartile range 69-82) and the median eGFRcreat 38 mL/min m(2) (interquartile range 33-49). Overall mortality was lower on the first and on the second tertiles of cystatin C than on the third one (HR = 0.060; 95% CI: 0.008-0.447 and HR = 0.094; 95% CI: 0.022-0.406, resp.). Deaths related to the creatinine tertiles followed the same pattern, but differences were not as large. Cardiovascular mortality was lower on the second than on the third cystatin C tertile (HR = 0.198; 95% CI: 0.040-0.987), but it did not show differences on the first and the second creatinine tertiles compared with the third one (HR = 0.126; 95% CI: 0.013-1.265 and HR = 0.403; 95% CI: 0.093-1.740). The only independent predictors of mortality during followup were baseline cystatin C (OR = 0.100; 95% CI: 0.021-0.463) and baseline uric acid (OR = 1.377; 95% CI: 1.070-1.773). Conclusion. Cystatin C may be an alternative to creatinine for detecting a high risk of death and cardiovascular events in a population with CKD.

Extracellular vesicle markers in relation to obesity and metabolic complications in patients with manifest cardiovascular disease

Background

Alterations in extracellular vesicles (EVs), including exosomes and microparticles, contribute to cardiovascular disease. We hypothesized that obesity could favour enhanced release of EVs from adipose tissue, and thereby contribute to cardiovascular risk via obesity-induced metabolic complications. The objectives of this study were: 1) to investigate the relation between the quantity, distribution and (dys) function of adipose tissue and plasma concentrations of atherothrombotic EV-markers; 2) to determine the relation between these EV-markers and the prevalence of the metabolic syndrome; and 3) to assess the contribution of EV markers to the risk of incident type 2 diabetes.

Methods

In 1012 patients with clinically manifest vascular disease, subcutaneous and visceral fat thickness was measured ultrasonographically. Plasma EVs were isolated and levels of cystatin C, serpin G1, serpin F2 and CD14 were measured, as well as fasting metabolic parameters, hsCRP and adiponectin. The association between adiposity, EV-markers, and metabolic syndrome was tested by multivariable linear and logistic regression analyses. As sex influences body fat distribution, sex-stratified analyses between adipose tissue distribution and EV-markers were performed. The relation between EV-markers and type 2 diabetes was assessed with Cox regression analyses.

Results

Higher levels of hsCRP (β 5.59; 95% CI 3.00–8.18) and lower HDL-cholesterol levels (β-11.26; 95% CI −18.39 – -4.13) were related to increased EV-cystatin C levels, and EV-cystatin C levels were associated with a 57% higher odds of having the metabolic syndrome (OR 1.57; 95% CI 1.19–2.27). HDL-cholesterol levels were positively related to EV-CD14 levels (β 5.04; 95% CI 0.07–10.0), and EV-CD14 levels were associated with a relative risk reduction of 16% for development of type 2 diabetes (HR 0.84, 95% CI 0.75–0.94), during a median follow up of 6.5 years in which 42 patients developed type 2 diabetes.

Conclusions

In patients with clinically manifest vascular disease, EV-cystatin C levels were positively related, and EV-CD14 levels were negatively related to metabolic complications of obesity.