Urinary albumin excretion is independently associated with C-reactive protein levels in overweight and obese nondiabetic premenopausal women

Non-Alcoholic Fatty Liver Disease Markers Associated with Fasting Serum Insulin and Urinary Albumin Excretion Independent of Fasting Plasma Glucose

Objective: We examined the association between non-alcoholic fatty liver disease (NAFLD) markers and fasting serum immunoreactive insulin (FIRI) and urinary albumin excretion (UAE). Subjects and methods: This study comprised Periods I and II from January 2007 to May 2009, and from June 2009 to December 2011, respectively. After excluding people with ethanol intake ≥210 g/week in men and ≥140 g/week in women, 961 people (613 men, 348 women; mean age: 44 years) were included. We evaluated the fatty liver using ultrasonography score (FLUS) and measured liver enzymes. Results: The mean observation period was 25 ± 9 months. We stratified people into two groups by fasting plasma glucose (FPG) in Period I. The cutoff point between the lower FPG and higher FPG was 100 mg/dL. In regression analysis, serum alanine aminotransferase (ALT) (p < 0.001), FLUS (p < 0.001) and γ-glutamyl transpeptidase (GGTP) (p = 0.022) in Period I were independently associated with FIRI in Period II, whereas in all participants FPG was not. ALT (p < 0.001) and GGTP (p = 0.001) were also independently associated with UAE in people with FPG < 100 mg/dL in Period II. Conclusions: Some NAFLD markers were associated with FIRI and UAE independently of fasting plasma glucose.

Gestational Diabetes Mellitus and Renal Function: A Prospective Study With 9- to 16-Year Follow-up After Pregnancy

OBJECTIVE

To examine whether gestational diabetes mellitus (GDM), independent of subsequent diabetes, is an early risk factor for renal impairment long term after the index pregnancy.

RESEARCH DESIGN AND METHODS

In the Diabetes & Women's Health (DWH) study (2012-2016), we examined the independent and joint associations of GDM and subsequent diabetes with long-term renal function among 607 women with and 619 women without GDM in the Danish National Birth Cohort (DNBC) index pregnancy (1996-2002). At median follow-up of 13 years after the index pregnancy, serum creatinine (mg/dL) and urinary albumin (mg/L) and creatinine (mg/dL) were measured, from which estimated glomerular filtration rate (eGFR) (mL/min/1.73 m2) and urinary albumin-to-creatinine ratio (UACR) (mg/g) were derived.

RESULTS

Compared with women without GDM or subsequent diabetes, women with a GDM history had significantly higher eGFR even if they had not subsequently developed diabetes (adjusted β-coefficient [95% CI] = 3.3 [1.7, 5.0]). Women who had a GDM history and later developed diabetes (n = 183) also had significantly higher UACR [exponent β = 1.3 [95% CI 1.1, 1.6]) and an increased risk of elevated UACR (≥20 mg/g) [adjusted relative risk [95% CI] = 2.3 [1.1, 5.9]) compared with women with neither. After adjusting for potential confounders including prepregnancy BMI and hypertension, GDM without subsequent diabetes was not related to UACR.

CONCLUSIONS

Women who develop GDM in pregnancy were more likely to show increased eGFR levels 9-16 years postpartum, which could indicate early stages of glomerular hyperfiltration and renal damage. However, only those who subsequently developed diabetes showed overt renal damage as evidenced by elevated UACR.

Inflammation gene variants and susceptibility to albuminuria in the U.S. population: analysis in the Third National Health and Nutrition Examination Survey (NHANES III), 1991-1994

BACKGROUND

Albuminuria, a common marker of kidney damage, serves as an important predictive factor for the progression of kidney disease and for the development of cardiovascular disease. While the underlying etiology is unclear, chronic, low-grade inflammation is a suspected key factor. Genetic variants within genes involved in inflammatory processes may, therefore, contribute to the development of albuminuria.

METHODS

We evaluated 60 polymorphisms within 27 inflammatory response genes in participants from the second phase (1991-1994) of the Third National Health and Nutrition Examination Survey (NHANES III), a population-based and nationally representative survey of the United States. Albuminuria was evaluated as logarithm-transformed albumin-to-creatinine ratio (ACR), as ACR ≥ 30 mg/g, and as ACR above sex-specific thresholds. Multivariable linear regression and haplotype trend analyses were conducted to test for genetic associations in 5321 participants aged 20 years or older. Differences in allele and genotype distributions among non-Hispanic whites, non-Hispanic blacks, and Mexican Americans were tested in additive and codominant genetic models.

RESULTS

Variants in several genes were found to be marginally associated (uncorrected P value < 0.05) with log(ACR) in at least one race/ethnic group, but none remained significant in crude or fully-adjusted models when correcting for the false-discovery rate (FDR). In analyses of sex-specific albuminuria, IL1B (rs1143623) among Mexican Americans remained significantly associated with increased odds, while IL1B (rs1143623), CRP (rs1800947) and NOS3 (rs2070744) were significantly associated with ACR ≥ 30 mg/g in this population (additive models, FDR-P < 0.05). In contrast, no variants were found to be associated with albuminuria among non-Hispanic blacks after adjustment for multiple testing. The only variant among non-Hispanic whites significantly associated with any outcome was TNF rs1800750, which failed the test for Hardy-Weinberg proportions in this population. Haplotypes within MBL2, CRP, ADRB2, IL4R, NOS3, and VDR were significantly associated (FDR-P < 0.05) with log(ACR) or albuminuria in at least one race/ethnic group.

CONCLUSIONS

Our findings suggest a small role for genetic variation within inflammation-related genes to the susceptibility to albuminuria. Additional studies are needed to further assess whether genetic variation in these, and untested, inflammation genes alter the susceptibility to kidney damage.

Aggravation of albuminuria by metabolic syndrome in type 2 diabetic Asian subjects

AIMS

We investigated the relationship of urinary albumin excretion (UAE) to metabolic syndrome and type 2 diabetes in Asian.

METHODS

A total of 446 subjects (187 without diabetes and 259 with type 2 diabetes) were enrolled in this study. The components of metabolic syndrome, high sensitivity C-reactive protein (hs-CRP) and UAE were assessed. Based on metabolic syndrome and diabetes status, participants were categorized into one of the following groups: neither metabolic syndrome nor diabetes (MS-DM-), metabolic syndrome without diabetes (MS+DM-), diabetes without metabolic syndrome (MS-DM+) and both metabolic syndrome and diabetes (MS+DM+).

RESULTS

The UAE in the MS+DM- group was higher than that in the MS-DM- group (P<0.001) and lower than that in the MS+DM+ group (P<0.001), but not significantly different from that in the MS-DM+ group (P=0.349). The trend of increasing UAE in these four groups was independent of hs-CRP.

CONCLUSION

UAE was lowest in subjects with neither metabolic syndrome nor diabetes and highest in subjects with both metabolic syndrome and type 2 diabetes; however, there was no significant difference between the metabolic syndrome alone group and the type 2 diabetes alone group.

Impact of the metabolic syndrome on the predictive values of new risk markers in the general population

Although the metabolic syndrome (MetS) is positively associated with high-sensitivity C-reactive protein (hsCRP), negatively associated with N-terminal pro-brain natriuretic peptide (Nt-proBNP) and inconsequently related to urine albumin/creatinine ratio (UACR) they are all associated with cardiovascular events. Therefore, we wanted to determine the influence of MetS on the predictive values of UACR, hsCRP and Nt-proBNP. On the basis of the definition of MetS by the International Diabetes Federation, a Danish population sample of 1983 apparently healthy subjects was divided into three groups: 530 subjects without any elements of MetS, 1093 subjects with some elements of MetS and 360 subjects with MetS. During the following 9.5 years the composite end point of cardiovascular death, non-fatal myocardial infarction or stroke (composite cardiovascular end point, CEP) occurred in 204 subjects. In Cox-regression analyses adjusting for age, gender and smoking, all three cardiovascular risk markers predicted CEP independently of MetS. Despite no significant interaction with MetS, high log(hsCRP) was associated with CEP primarily in subjects without any elements of MetS (hazard ratio (HR)=4.5 (1.5-14.0), P<0.01), log(Nt-proBNP) primarily in subjects with some elements of MetS (HR=3.0 (1.6-5.6), P<0.01), and logUACR independently of elements of MetS. Pre-specified gender-adjusted (men/women) cutoff values of hsCRP > or = 6.0/7.3 mg l(-1) predicted CEP in subjects without elements of MetS with positive and predictive values of 11.5 and 98%, respectively. UACR > or = 0.73/1.06 mg mmol(-1) predicted CEP in subjects with MetS with positive and predictive values of 23.5 and 93%, respectively. In apparently healthy subjects, high hsCRP was associated with CEP primarily in subjects without MetS, high Nt-proBNP in subjects with elements of MetS and UACR independently of MetS.

Microalbuminuria: risk factor and potential therapeutic target for stroke?

Microalbuminuria (MA), a microvascular irregularity of the blood-urine interface within kidney glomeruli, may reflect the renal sign of global endothelial dysfunction, and has been associated with an elevated risk of serious cardiovascular events including stroke. This relationship appears graded, with higher levels of MA being independently associated with a greater magnitude of vascular risk over time. Furthermore, the presence of MA appears to independently predict poorer clinical outcomes following acute stroke. Screening for MA is relatively easy and inexpensive and could be effective in identifying stroke patients at risk for unfavorable outcomes. Reduction of subclinical albuminuria in stroke patients could be a clinically relevant endpoint worthy of pursuit by pharmacological treatment since the antiproteinuric effects of several established therapies appear to parallel better cardiovascular prognosis including better stroke outcomes, among subjects at high vascular risk. This review depicts the compelling epidemiological and clinical evidence relating MA to stroke, and presents the rationale for conducting future studies to assess the role of MA as a potential therapeutic target in persons with, or at risk for stroke.

Associations between microalbuminuria and animal foods, plant foods, and dietary patterns in the Multiethnic Study of Atherosclerosis

BACKGROUND

The balance between the intake of animal and the intake of plant foods may influence renal vascular integrity as reflected by urinary albumin excretion.

OBJECTIVE

We assessed cross-sectional associations between urinary albumin excretion and dietary patterns and intake of plant and animal foods.

DESIGN

At baseline, diet (food-frequency questionnaire) and the urinary albumin-to-creatinine ratio (ACR; spot urine collection) were measured in 5042 participants in the Multi-Ethnic Study of Atherosclerosis who were aged 45-84 y and were without clinical cardiovascular disease, diabetes, or macroalbuminuria (sex-adjusted ACR >or= 250). We derived dietary patterns by principal components analysis. We also summed food groups to characterize plant food intake (fruit, fruit juice, vegetables, nuts, legumes, whole grains, and refined grains), animal food intake (red meat, processed meat, poultry, fish, high-fat dairy, and low-fat dairy), and nondairy animal food intake.

RESULTS

After adjustment for multiple demographic and lifestyle confounders, a dietary pattern characterized by high consumption of whole grains, fruit, vegetables, and low-fat dairy foods was associated with 20% lower ACR across quintiles (P for trend = 0.004). Neither total animal nor total plant food intake was associated with ACR. However, greater low-fat dairy consumption was associated with 13% lower ACR across quartiles (P for trend = 0.03). Total nondairy animal food consumption was associated with 11% higher ACR across quintiles (P for trend = 0.03).

CONCLUSIONS

A high intake of low-fat dairy foods and a dietary pattern rich in whole grains, fruit, and low-fat dairy foods were both associated with lower ACR. In contrast, collectively, nondairy animal food intake was positively associated with ACR.

Relation of left ventricular hypertrophy to microalbuminuria and C-reactive protein in children and adolescents with essential hypertension

Microalbuminuria (MA) and C-reactive protein (CRP) levels are predictors of increased risk for left ventricular hypertrophy (LVH). Whether the strength of association between CRP and LVH is comparable to that of MA in hypertensive children is unknown. CRP and MA were measured in 64 children and adolescents with essential hypertension (HTN). In the entire population, CRP and MA showed positive relations with body mass index (BMI) (r = 0.30, p = 0.04 and r = 0.32, p = 0.04, respectively), systolic blood pressure (SBP) (r = 0.63, p = 0.03 and r = 0.58, p = 0.03, respectively), and LVH (r = 0.86, p < 0.001 and r = 0.81, p < 0.001, respectively). Patients with LVH (n = 23) had significantly higher BMI (p = 0.32), increased SBP (p = 0.031), and higher levels of CRP (p < 0.001) and MA (p < 0.001) compared with those without LVH. Multiple linear regression analysis demonstrated that CRP (r = 2.11, p < 0.001), MA (r = 1.94, p < 0.003), BMI (r = 0.53, p = 0.02), and SBP (r = 0.48, p = 0.04) were significantly associated with LVH. By analysis of covariance, CRP and MA were significantly different between patients who had LVH and those without LVH after adjustment for age, gender, BMI, SBP, SBP index, and diastolic blood pressure (p < 0.001 for the two markers). In conclusion, the strength of association between LVH and CRP is comparable to that of MA in children and adolescents with essential HTN.

Interrelationships between inflammation, C-reactive protein, and insulin resistance

The recognition that inflammation plays a fundamental role in atherothrombosis has led to the measurement of circulating inflammatory biomarkers such as high-sensitivity C-reactive protein (hs-CRP) as a means of improving cardiovascular disease detection and prevention. Clinically, levels of hs-CRP >3 mg/L indicate elevated risk for myocardial infarction and stroke, even among apparently healthy individuals with low-to-normal lipid levels. Emerging laboratory and epidemiologic data now link inflammation and hs-CRP to insulin resistance in that hs-CRP levels have been associated with impaired insulin sensitivity and the development of dysglycemic conditions, including the cardiometabolic syndrome and incident type 2 diabetes. hs-CRP has also been associated with each of the individual components of the cardiometabolic syndrome. Furthermore, in large prospective studies, hs-CRP adds prognostic information about cardiovascular risk beyond that provided by the cardiometabolic syndrome. These findings have led to discussion about the addition of hs-CRP measurement to the current definition of the cardiometabolic syndrome to improve detection of risk for both diabetes and cardiovascular events in patients. Multiple clinical studies are now underway that are evaluating whether agents traditionally used to improve glycemic control may also significantly reduce hs-CRP.

Microalbuminuria in pediatric obesity: prevalence and relation to other cardiovascular risk factors

BACKGROUND

Microalbuminuria (MA) has emerged as a strong predictor of cardiovascular (CV) events, even in nondiabetic adults. While the mechanisms behind this association remain to be established, most studies suggest that MA is the result of increased vascular leakage denoting endothelial dysfunction associated with early vasculopathy.

OBJECTIVE

To examine if a urine albumin creatinine ratio (UACR) in the microalbuminuric range is related to metabolic markers of CV risk in obese and pre-diabetic youth recruited from an obesity clinic.

METHODS

MA was defined as a UACR between 2.0 and 20 mg/mmol. Subjects with gross proteinuria (UACR>20 mg/mmol) were excluded from the study. Analyses were performed to assess the relationship of MA and markers of CV risk, including body mass index (BMI), % body fat, blood pressure (BP), lipid profile, inflammatory markers, insulin sensitivity indexes and degrees of oral glucose tolerance. MA was also correlated with risk factor constellations unique to the metabolic syndrome, a distinct CV risk entity.

RESULTS

Postchallenge alterations in glucose metabolism and overall loss in insulin sensitivity were strongly and positively correlated with the presence of MA (P = 0.002 and 0.01, respectively). Neither the metabolic syndrome nor any of the individual CV risk factors examined were associated with MA.

CONCLUSIONS

These data suggest that early glucose toxicity, as reflected by postchallenge elevations in plasma glucose even below the diagnostic cutoff for diabetes mellitus may contribute to the presence of MA. Whether MA is equally as predictive of CV disease in youth, as in adulthood, remains to be investigated.

The decrease in C-reactive protein concentration after diet and physical activity induced weight reduction is associated with changes in plasma lipids, but not interleukin-6 or adiponectin

Subclinical inflammation is a risk factor for cardiovascular disease. The mechanisms underlying increased levels of inflammatory markers and their changes in response to weight loss are not fully understood yet. It has been proposed that elevated concentrations of C-reactive protein (CRP) are mediated by cytokines produced in adipose tissue. We investigated the changes in circulating CRP after weight reduction, in relation to parameters relevant to the metabolic syndrome. Forty 25- to 35-year-old obese female volunteers participated in an intervention program of dietary education and supervised physical activity for a period of 9 weeks. Anthropological parameters and biochemical measurements (high-sensitivity CRP [hsCRP], plasma lipoproteins, interleukin 6 [IL-6], adiponectin) were analyzed before and after the intervention. Body mass index decreased by more than 7% from 31.5 +/- 4.1 to 29.1 +/- 3.9. Plasma free fatty acid (FFA) concentrations decreased by 30%, high-density lipoprotein cholesterol increased by 8%, and fasting insulin concentrations decreased by 15%. There were no significant changes in either low-density lipoprotein cholesterol or triacylglycerol concentrations. Subcutaneous and visceral adipose tissue mass decreased by 12% and 18%. High-sensitivity CRP concentrations decreased by 30%; however, mean plasma IL-6 and adiponectin concentrations remained unchanged. In linear regression analysis, the changes in plasma hsCRP concentrations were associated with baseline hsCRP concentration, change in triacylglycerols and FFA concentrations, and in waist circumference. The decrease in hsCRP concentration after weight reduction does not appear to be mediated by decreases in circulating IL-6 or adiponectin concentrations; however, change in hsCRP concentration is related to changes in waist circumference and lipid metabolism, reflected by plasma triacylglycerol and FFA levels.

Relation of microalbuminuria to adiponectin and augmented C-reactive protein levels in men with essential hypertension

Microalbuminuria, and recently, hypoadiponectinemia, have been associated with progression of atherosclerotic disease and increased cardiovascular risk. We examined the possible associations of urinary albumin excretion, expressed as the ratio of albumin to creatinine (ACR), with plasma adiponectin and high-sensitivity C-reactive protein (hs-CRP) levels in men who had essential hypertension. The study population consisted of 108 men who did not have diabetes and were newly diagnosed with stage I to II essential hypertension (age 44.6 years, office blood pressure 148/95 mm Hg) and 110 men matched according to age and body mass index as controls. According to ACR values, which were determined as the average of 2 nonconsecutive overnight spot urine samples, subjects who had hypertension were categorized into 2 groups: those who had microalbuminuria (n = 28; mean ACR 30 to 300 mg/g) and those who had normal albuminuria (n = 80; mean ACR <30 mg/g). Subjects who had hypertension compared with controls exhibited higher ACR and log hs-CRP levels and a trend toward lower log adiponectin values (p = 0.062), whereas those who had normal albuminuria compared with controls had similar log adiponectin levels but significantly higher levels of ACR and log hs-CRP. Moreover, subjects who had hypertension and microalbuminuria compared with those who had hypertension and normal albuminuria had higher log hs-CRP and lower log adiponectin concentrations independently of confounding factors. Among those who had hypertension, ACR exhibited an independent positive correlation with log hs-CRP and a negative correlation with log adiponectin. Multiple linear regression analysis showed that age, body mass index, systolic blood pressure, log hs-CRP, and log adiponectin were significant independent predictors of the ACR. In conclusion, microalbuminuria is accompanied by decreased adiponectin and increased hs-CRP levels in the setting of essential hypertension, reflecting a rather diffuse atherosclerotic process.

Microalbuminuria and C-reactive protein: Similar messengers of cardiovascular risk?

C-reactive protein (CRP) and urinary albumin excretion are both determinants of cardiovascular risk. The first is closely related to systemic and vascular low-grade inflammation, the latter is considered to be a marker of endothelial dysfunction. Because of these properties, one might presume them to be closely interrelated. In this article, we review the available evidence concerning the relationships of CRP and urinary albumin excretion, with each other and with other cardiovascular risk markers and factors. Should they be considered as dependent or independent risk markers, and which risk markers might be present in the cardiovascular risk estimation formula of the near future? The reasons that this formula might or should include CRP and urinary albumin excretion, rather than diabetes mellitus and the metabolic syndrome, are discussed.

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.

Low-grade inflammation and microalbuminuria in hypertension

Background- Albuminuria and C-reactive protein (CRP), a marker of systemic low-grade inflammation, are frequently elevated in essential hypertension and predict cardiovascular prognosis independent of conventional risk factors. However, in spite of their potentially important links, the interrelationships between the 2 parameters have not been explored in depth in hypertensive patients.

METHODS AND RESULTS

Albuminuria (the mean of 3 overnight urine collections), high-sensitive CRP (hs-CRP), 24-hour blood pressure (BP), weight, lipids, poststimulative (75 g PO) plasma glucose, insulin, and insulin sensitivity by the homeostasis model assessment model were evaluated in 220 never treated, nondiabetic, uncomplicated essential hypertensive men. Albuminuria > or =15 microg/min was defined as microalbuminuria and hs-CRP values above and below median (2.3 mg/L) as high and low, respectively. Concentric left ventricular hypertrophy was diagnosed by echocardiography, and a full-blown metabolic syndrome was identified in presence of hypertension and at least 3 of following: obesity, subclinical hyperglycemia, low high-density lipoprotein (HDL) and high triglycerides. Microalbuminuria was present in 54 patients, 29 with high hs-CRP characterized by higher 24-hour systolic BP, postload glucose, body mass index, lower HDL cholesterol, more frequent metabolic syndrome, concentric LVH, and active smoking than those with either isolated microalbuminuria (n=27) or normoalbuminuria.

CONCLUSIONS

Microalbuminuria accompanied by evidence of subclinical inflammation is a strong correlate of metabolic abnormalities in essential hypertension and identifies a patient subset at very high cardiovascular risk. In contrast, isolated microalbuminuria may represent a distinct pathophysiological condition characterized by a more benign profile and possibly a better prognosis.

Marcadores biológicos de inflamación vascular y aterosclerosis subclínica en el síndrome metabólico

BACKGROUND AND OBJECTIVE

The metabolic syndrome (MS) is linked to an increase of cardiovascular mortality and morbidity, the pathological substrate of cardiovascular events being atherosclerosis. Inflammatory phenomena play a role in the genesis of atherosclerosis. The aim of this study was to analyze the vascular (adhesins) and systemic [interleukins, amyloid A serum protein (AAS), C reactive protein (PCR)] inflammation markers as well as hemodynamic parameters and the presence or absence of subclinical atherosclerosis measured by intima-media thickness (TIM) determination in MS.

PATIENTS AND METHOD

In this transversal study we enrolled 29 patients (18 men,11 women) with a diagnosis of MS. We assessed interleukins (IL-1beta, IL-6, TNF-alpha, TGF-beta, MCP-1), intercellular and intervascular adhesions molecules (sICAM-1, sVCAM-1), systemic inflammation markers (PCR, AAS), microalbuminuria and, as a lipidic oxidation marker, urinary F2 isoprostanes (F2I). TIM was measured by ultrasounds. Ten healthy people with a similar age were included as a control group.

RESULTS

Patients with MS, when compared with the control group, showed higher levels of homocysteine (10 [0.5] vs 7.9 [0.5] micromol/l; p < 0.05), sICAM1 (263 [13] vs 203 [14] ng/ml; p < 0.01), IL-6 (7.1 [0.5] vs 4.6 [0.6] pg/ml; p < 0.05), TGF-beta (34 [1.7] vs 26 [1.4] ng/ml; p < 0.01), PCR (0.69 [0.07] vs 0.23 [0.03] mg/dl; p < 0.001), AAS (9.7 [0.7] vs 6.7 [0.7] microg/ml; p < 0.01), microalbuminuria (32 [13] vs 3.2 [0.14] mg/g creatinine; p < 0.05), and F2I (22.4 [2.5] vs 9.1 [0.69] pg/mg creatinine; p < 0.001). TIM in the MS group was greater than in the control group (1.14 [0.14] vs 0.79 [0.02] mm; p < 0.05). F2I values were directly correlated with TIM, systolic arterial pressure and pulse pressure.

CONCLUSIONS

Our results show that in MS there is an increase of vascular inflammation and lipooxidation markers and a higher prevalence of subclinical atherosclerosis.

Strong association of C-reactive protein with body mass index and 2-h post-challenge glucose in non-diabetic, non-smoker subjects without hypertension

AIMS

Increases in C-reactive protein (CRP) levels have been shown to be associated with cardiovascular diseases as well as asymptomatic atherosclerosis and to be closely related to traditional cardiovascular risk factors. The aim of this study was to determine the clinical and biochemical characteristics associated with CRP in non-diabetic, non-smoker subjects without hypertension.

METHODS

A 75-g oral glucose tolerance test was performed on 305 Japanese subjects aged 40-70 years who were undergoing health examinations. We recruited non-diabetic, non-smoker subjects without hypertension. Subjects with known cardiovascular diseases, chronic or acute inflammation, malignant diseases, or autoimmune disorders were excluded. Plasma high-sensitivity CRP was measured in 125 subjects who satisfied the admission criteria.

RESULTS

Plasma CRP levels were significantly higher in the 28 subjects with impaired glucose tolerance (IGT) than that in the 97 subjects with normal glucose tolerance (NGT) (median 0.53, range 0.18-1.10 mg/l vs. median 0.32, range 0.17-0.49 mg/l; P = 0.032). There was a positive correlation of CRP with body mass index (BMI), triglycerides, uric acid, fasting glucose, oral glucose tolerance test (OGTT) 1-h glucose, OGTT 2-h glucose, and a negative correlation with HDL cholesterol. Multivariate regression analysis identified BMI (F = 8.57, P = 0.004) and OGTT 2-h glucose (F = 5.96, P = 0.016) as independent predictors for CRP.

CONCLUSIONS

BMI and OGTT 2-h glucose are the most important predictors for plasma CRP in non-diabetic, non-smoker subjects without hypertension.

C-Reactive Protein Modifies the Relationship Between Blood Pressure and Microalbuminuria

C-reactive protein (CRP) and microalbuminuria reflect intimately related components of the atherosclerotic disease process. Epidemiological studies found only modest associations between CRP and microalbuminuria. Blood pressure, one of the components of the metabolic syndrome in the general population, is the main determinant of microalbuminuria in diabetes and hypertension. We questioned whether CRP modifies the relationship of blood pressure and other cardiovascular risk factors with microalbuminuria in a cross-sectional study in 8592 inhabitants from Groningen, The Netherlands. The crude data showed an increase in the prevalence of microalbuminuria with increasing CRP quartiles (4.8, 9.6, 14.5, and 18.6%, P<0.0001). On stratification for cardiovascular risk factors, the data revealed a significant and positive interaction between mean arterial pressure (MAP) and quartiles of CRP with respect to the risk of microalbuminuria (Wald statistic 9.2, P=0.03). In subjects with a MAP <90 mm Hg, a nonsignificant trend in the association between CRP quartiles and microalbuminuria was found (prevalence: 3.9%, 5.8%, 6.6%, 8.7%; P=0.11). This trend was much steeper and significant in subjects with an MAP >90 mm Hg (prevalence: 6.7%, 13.6%, 20.4%, 25.1%; P<0.0001). Controlling for other risk factors in multivariate analyses, the positive interaction persisted (P=0.0004). No significant interactions between other risk factors and CRP with respect to the risk of microalbuminuria were encountered. Thus, CRP modifies the relation between blood pressure and microalbuminuria.

Relation of homocysteine and C-reactive protein to urinary albumin loss

This study shows that elevated high-sensitivity C-reactive protein and plasma total homocysteine contribute independently to the likelihood of an increased urinary albumin:creatinine ratio. This result suggests that total homocysteine and C-reactive protein may be acting by separate mechanistic pathways.

C-reactive protein and microalbuminuria differ in their associations with various domains of vascular disease

C-reactive protein (CRP) and microalbuminuria (MA) have been identified as risk markers for cardiovascular disease (CVD). We questioned whether CRP and MA are similar markers of vascular disease in different regions of the vascular tree like the heart, kidneys and extremities or if they differ in their relationships with these vascular beds. Baseline levels of CRP and urinary albumin were measured in 6669 non-diabetic participants in the Prevention of Renal and Vascular ENdstage Disease (PREVEND) study, a Dutch cohort derived from the general population. We defined three domains of vascular disease; coronary heart disease (myocardial infarction or infarct pattern on the ECG), renal insufficiency (creatinine clearance <60 ml min(-1)) and peripheral artery disease (ankle brachial index <0.9 or lower limb revascularisation). The prevalence of an elevated CRP (27.7 vs. 17.9%) and MA (17.5 vs. 10.4%) were increased in subjects with vascular disease as compared with subjects without CVD. The prevalence of an elevated CRP was equal in subjects with either coronary heart disease, renal insufficiency or peripheral artery disease (28.4 vs. 29.5 vs. 26.0%, NS), whereas MA was most prevalent in subjects with coronary heart disease (22.5 vs. 12.8 vs. 14.9%, P<0.05). Using multivariate analyses, CRP was independently associated with all three domains of vascular disease, whereas MA was independently associated with coronary heart disease only. In addition, we found synergistic contributions of an elevated CRP and older age to the risk of vascular disease in all three domains. Thus, CRP and MA are risk markers for vascular disease, each showing a different risk profiling for different vascular beds.

HRT does not improve urinary albumin excretion in postmenopausal diabetic women

The effect of 6 months combined, continuous hormone replacement therapy (HRT) with conjugated equine oestrogen (0.625 mg) and medroxyprogesterone acetate (2.5 mg) on albumin/creatinine ratio (ACR) was determined in postmenopausal diabetic women in a randomised, controlled study. Mean (interquartile range) change in plasma ACR was not (P=0.96) different in women receiving HRT [2 (-11, 21) mg/g, n=20] compared with those randomised to placebo [2 (-1, 14) mg/g, n=27]. Also, the proportion of women with microalbuminuria did not change (P=0.75) during HRT (baseline, 0.45; end of study, 0.53). Furthermore, several risk factors for microalbuminuria including systolic blood pressure (SBP), fasting blood glucose, glycated haemoglobin (HbA1c) and adiposity did not vary significantly during HRT. These data suggest that 6 months HRT does not reverse microalbuminuria caused by prolonged hyperglycaemia and other risk factors that underlie leakage of albumin into the urine in postmenopausal women with type 2 diabetes.

Mediators of inflammation correlate with microalbuminuria in patients with non-Hodgkin's lymphoma

Recent studies have demonstrated a high frequency of minor glomerular leakage of albumin in cancer patients. Pathogenic mechanisms of increased urinary albumin excretion (UAE) in malignancies remain to be clarified. We have attempted to identify whether microalbuminuria in lymphoma patients is associated with inflammatory mediators and the acute-phase response. UAE, urinary excretion of beta2-microglobulin and IgG, and serum levels of interleukin 6 (IL-6), tumour necrosis factor alpha (TNF-alpha) and C-reactive protein (CRP) were determined in 113 patients with newly diagnosed non-Hodgkin's lymphoma. We demonstrated a high frequency of microalbuminuria (>or= 20 microg/min) and UAE correlated strongly with serum levels of CRP, IL-6 and TNF-alpha. UAE, CRP, IL-6 and TNF-alpha were significantly higher in patients with advanced disease stage, B symptoms and in high-risk patients according to the International Prognostic Index. Urinary excretion of beta2-microglobulin was unaffected in patients with increased UAE. However, UAE was significantly correlated with urinary excretion of IgG, suggesting an altered size selectivity of the glomerular filtration barrier. This is the first study that shows a direct correlation between microalbuminuria and proinflammatory cytokines in malignancies, indicating a pathogenic relationship between inflammation and glomerular leakage of albumin. Future efforts should focus on the pathophysiological cause-effect mechanisms and larger studies are needed to confirm the clinical significance of UAE.

Association of albuminuria and the metabolic syndrome

Microalbuminuria clusters with the metabolic syndrome, and both conditions predict cardiovascular disease mortality. The reported relationships of microalbuminuria with the individual components of the metabolic syndrome (i.e., hyperglycemia, insulin resistance, hypertension, dyslipidemia, abdominal obesity) are variable. Each of these components, as well as intrauterine effects and diet and other lifestyle factors, may contribute to elevated risk of microalbuminuria in certain population groups. Recent evidence indicates a role for oxidation and inflammation in cardiovascular disease, and endothelial dysfunction (exacerbated by factors such as dyslipidemia) may be the mediator of this relationship. Because endothelial dysfunction can also be manifested as microalbuminuria, this provides a potential explanation of the observed association of the metabolic syndrome, chronic inflammation, and microalbuminuria.