Raised C-reactive protein levels in patients with recent onset type 1 diabetes

Early Markers of Atherosclerosis in Children and Adolescents with Type 1 Diabetes Mellitus

OBJECTIVES

To detect early atherosclerosis changes using flow-mediated dilation (FMD) of the brachial artery, carotid intima-media thickness (CIMT), inflammatory markers (hs-CRP, IL-6), and endothelial markers (sICAM and sVCAM).

METHODS

The authors recruited 4 to 18-y-old children with type 1 diabetes mellitus (T1DM) and age- and sex-matched normal children, excluding those with familial hypercholesterolemia, syndromic disorders, and cardiovascular disease. CIMT and FMD were measured in both the groups. Biomarkers hs-CRP, IL-6, sICAM, and sVCAM, were analyzed in the T1DM group.

RESULTS

Forty T1DM children and 40 controls with 27 (67.5%) girls were enrolled in each group. The mean age was 9.68 y. The T1DM group had 4 (10%) obese and 4 (10%) overweight children. Among cases, 9 (22.5%) had diabetes for > 5 y, 24 (60%) required daily insulin between 0.8 and 1.2 IU/kg/d and 26 (65%) had HbA1c > 10 g/dL. The CIMT values were significantly higher in cases (0.69 mm) than in controls (0.59 mm); 29 (72.5%) cases had abnormal combined CIMT values. FMD was lesser in cases than in controls but not significant. The median values of hs-CRP, IL-6, sICAM, sVCAM were 0.81 mg/L, 6.27 pg/mL, 46.33 ng/mL and 668.81 ng/mL, respectively. A significant correlation of IL-6 with CIMT (r = 0.543, p =  < 0.001) and sICAM with FMD (r =  -0.397, p = 0.011) was observed. VCAM was low in the obese and overweight children.

CONCLUSION

Children with type 1 diabetes had higher CIMT than normal children, whereas FMD did not differ. The association between elevated inflammatory markers with high CIMT and low FMD indicates that inflammation plays an essential role in endothelial dysfunction.

Urine π-Glutathione S-transferase but not Tamm-Horsfall protein correlates with carotid artery intima media thickness in childhood type1 diabetes

Background

Renal disease remains a serious threat in patients with insulin-dependent (type1) diabetes. Hence its detection early in the life of patients with type1 diabetes is crucial. Several lines of evidence suggest similar mechanisms for the development of both renal and arterial disease. We sought to investigate in young patients with type1 diabetes whether π-Glutathione S-transferase to creatinine (π-GST:crea) and Tamm-Horsfall protein to creatinine (THP:crea) ratios, markers of distal tubular renal function, relate to subclinical markers of arterial disease, which appear to onset early and develop rapidly in type1 diabetes.

Methods

Seventy-one children and adolescents (median age and diabetes duration 14 and 6 years, respectively) with type1 diabetes for at least 6 months were assessed for timed urine levels of π-GST, THP, HbA1c, albumin, and plasma C-reactive protein (CRP). Carotid artery intima-media thickness (IMT), brachial artery flow-mediated dilatation (FMD), and cutaneous microvascular function were assessed by high-resolution ultrasound and laser Doppler, respectively.

Results

Two patients had microalbuminuria (> 20 μg/min), and were therefore removed from the study population. π-GST:crea ratio and THP:crea showed no relationship to the demographic, diabetes, or inflammatory indices. Lower π-GST:crea ratio was associated with greater IMT (p = 0.01, r = −0.29), particularly in female patients (p = 0.004, r = −0.49). The association of π-GST:crea ratio with IMT was stronger in patients with passive smoke exposure (p = 0.002, r = −0.43). Among post-pubertal patients, lower π-GST:crea ratio was also associated with lower microvascular response to Ach (acetylcholine; p = 0.03, r = 0.49).

Conclusions

In young patients with type1 diabetes, proximal tubular dysfunction as suggested by lower levels of π-GST:crea ratio seems to be paralleled by changes in arterial structure and microvascular function.

One size does not fit all glycemic targets for type 2 diabetes

The United Kingdom Prospective Diabetes Study, and Diabetes Control and Complications Trial have shown that aggressive glucose control, especially early in the natural history of the disease, might result in a significant reduction of microvascular as well as macrovascular complications. However, more recent trials have increased the level of complexity of the relationship between 'tight glucose control/chronic complications', with several factors influencing the risk-to-benefit ratio to be considered, such as age, presence of established complications and diabetes duration. According to this strategy, a more intensive goal is desirable for young patients with no cardiovascular disease, whereas less stringent control is suitable for all people who are relatively late in the natural history of diabetic complications. Numerous calls for an individualized therapy have been proposed during the past years, but still debated is the level of glucose lowering necessary to reduce complications balanced by the risk and costs of the means used. The present paper briefly reviews the rationale and the clinical trials that support specific glycemic goals towards a 'tailored' approach for the management of hyperglycemia in diabetes.

Effector and regulatory T cell subsets in diabetes-associated inflammation. Is there a connection with ST2/IL-33 axis? Perspective

Type 1 diabetes (DM1) is a chronic inflammatory disease, which when progresses leads to the development of late vascular complications. The disease involves impairments in regulatory and effector subsets of T lymphocytes, which suppress and maintain inflammatory response, respectively. ST2/IL-33 pathway is involved in T-cell-mediated immune response and might regulate the inflammatory process in several diseases. This review presents the latest research findings regarding effector and regulatory T cell subsets in the context of inflammation accompanying DM1 with particular focus on the ST2/IL-33 network and its possible association with T cell-mediated immunity.

Human C-reactive protein accentuates macrophage activity in biobreeding diabetic rats

OBJECTIVE

Type 1 diabetes (T1DM) is a pro-inflammatory state characterized by high C-reactive protein (CRP) levels. However, there is a paucity of data examining the role of CRP in promoting the pro-inflammatory state of diabetes. Thus, we examined the pro-inflammatory effects of human CRP using spontaneously diabetic bio-breeding (BB) rats.

METHODS

Diabetic rats (n=9/group) were injected with Human serum albumin (huSA) or Human CRP (hCRP, 20 mg/kg body weight; i.p.) for 3 consecutive days. Blood and peritoneal macrophages (MØ) were obtained following euthanasia. Peritoneal macrophages were used for measuring superoxide anion release, NF-κB DNA binding activity, proinflammatory mediator secretion.

RESULTS

hCRP administration resulted in significantly increased superoxide anion production, along with increased release of cytokines/chemokines, and plasminogen activator inhibitor (PAI-1) and Tissue Factor (TF) activity in diabetic rats compared to huSA. hCRP-treated BB rat MØ showed significant induction of protein kinase C (PKC)-alpha, PKC-delta and p47 phox expression and NF-κB compared to huSA.

CONCLUSIONS

Thus, our data suggest that human CRP exacerbates in-vivo the pro-inflammatory, pro-oxidant and procoagulant states of diabetes predominantly via increased macrophage activity and this could have implications with respect to vascular complications and anti-inflammatory therapies.

Insulin resistance, low-grade inflammation and type 1 diabetes mellitus

To assess the relationships between insulin resistance and low-grade inflammation in subjects with type 1 diabetes mellitus (T1DM) who do not have clinical macrovascular complications. A total of 120 subjects diagnosed with T1DM 14 years before were evaluated for the following: (1) sex, age, body mass index, waist-to-hip ratio (WHR), blood pressure, smoking, alcohol intake, insulin dose, HbA1c and lipid profile; (2) microvascular complications; (3) plasma concentrations of soluble fractions of tumour necrosis factor-α receptors type 1 and 2, interleukin-6, adiponectin, leptin and high-sensitivity C-reactive protein (hs-CRP); and (4) insulin resistance (estimation of the glucose disposal rate-eGDR). Those subjects with an eGDR below the median of the same sex group were classified as insulin resistant and the others as insulin sensitive. Insulin-resistant men, compared to the insulin-sensitive, had higher WHR (0.89 ± 0.08 vs. 0.83 ± 0.05; P < 0.01), higher systolic [121 (118-125) vs. 114 (108-120) mmHg; P = 0.01] and diastolic [73 (66-80) vs. 67 (70-73) mmHg; P = 0.02] blood pressures, higher HbA1c values [8.7 (8.1-9.9) vs. 7.5 (7.2-8.0) %; P < 0.01] and higher hs-CRP concentrations [1.16 (0.61-3.20) vs. 0.49 (0.31-0.82) mg/dl; P = 0.01], but no other significant differences between groups were found. Insulin-resistant women had higher WHR and HbA1c values, compared to the insulin-sensitive, but they did not have any other differences. In men, hs-CRP correlated significantly with WHR and HbA1c (r = 0.363; P = 0.016 and r = 0.317; P = 0.036, respectively), after adjusting for age, alcohol intake, smoking and microvascular complications. Insulin-resistant men with T1DM have an increase in plasma concentrations of hs-CRP. Central obesity and HbA1c are its main determinants.

Increased serum C-reactive protein concentration is associated with body mass index but not with glycated haemoglobin in patients with type 1 diabetes mellitus with body mass index within normal range

This study investigated whether serum C-reactive protein (CRP) concentration is increased in patients with type 1 diabetes mellitus with a normal body mass index (BMI) and whether BMI, glycated haemoglobin (HbA1c) and CRP are correlated in patients with type 1 diabetes. High-sensitivity CRP was determined by immunonephelometry and HbA1c by an immunoturbidimetric method in 30 patients with type 1 diabetes and 30 healthy individuals matched for age, sex and BMI. Median serum CRP concentration in patients with type 1 diabetes (1.34 mg/L) was significantly higher than healthy individuals (0.2 mg/L; p<0.0001). Positive correlation between CRP and BMI was observed (rho=0.598; p<0.0001), but no significant correlation was observed between CRP and HbA1c (rho=0.285; p=NS) in patients with type 1 diabetes. Increased CRP levels in type 1 diabetes patients do not appear to be associated with glycaemic control, and may reflect low-grade inflammation associated with atherosclerosis, as well as activation of innate immune activity.

Effect of menopause and use of contraceptives/hormone therapy on association of C-reactive protein and depression: a population-based study

OBJECTIVE

Unipolar depression has been found to associate with elevated C-reactive protein (CRP) levels in men, but findings among women have been conflicting. It has been hypothesized that this would be explained by a different hormonal environment (compared with men) and its changes throughout the lifecycle in women, but until now, the corresponding evidence has been lacking. We investigated the association between CRP levels and depressive symptoms in a population-based study in pre-, peri-, and postmenopausal women and, also, whether this association is affected by the use of exogenous hormones (contraceptives and postmenopausal hormone therapy).

METHODS

The entire age classes of those born in 1942, 1947, 1952, 1957, and 1962 and living in Pieksämäki, Finland, were invited (n=1294), and out of 730 women, 512 (70.1%) participated in this cross-sectional study in 1997 to 1998. Depressive symptoms were assessed by Beck's Depression Inventory-21 (BDI-21), and CRP was measured with a high-sensitivity CRP (hs-CRP) assay.

RESULTS

We found a positive correlation between hs-CRP levels and depressive symptoms in peri- and postmenopausal women not using exogenous hormones (Pearson correlation coefficient, r=.248, P<.001; and r=.343, P=.059, respectively). After multivariate adjustment, a statistically significant interaction was noted between hs-CRP levels and the exogenous hormone use on total score of BDI-21 (P=.022) among "peri- and postmenopausal women."

CONCLUSIONS

Our novel findings suggest that female hormones may have moderating effect at peri- and postmenopausal women on the association between elevated CRP levels and depressive symptoms. Further studies are, however, needed to confirm our findings.

Hs-CRP is associated with weight, BMI, and female sex but not with endothelial function in children with type 1 diabetes

BACKGROUND

Atherosclerosis is an inflammatory process, and high-sensitivity C-reactive protein (Hs-CRP), a marker of inflammation, predicts cardiovascular events in adults. Vascular endothelial and smooth muscle dysfunction, measurable precursors of atherosclerosis, begin in childhood. Therefore, we sought to determine if Hs-CRP is associated with vascular endothelial and smooth muscle dysfunction in children with type 1 diabetes mellitus (T1DM) and healthy control subjects.

METHODS

Hs-CRP and endothelial function assessed by flow-mediated dilatation (FMD) and smooth muscle function assessed by glyceryl-trinitrate (GTN)-induced dilatation were measured in 121 subjects with T1DM aged 14.1 (2.9) yr, of whom 31 were also studied at 4 and 8 wk, and in 33 healthy controls aged 14.2 (3.6) yr.

RESULTS

Hs-CRP did not differ between subjects with T1DM and healthy, age-matched controls. In both controls and subjects with T1DM, Hs-CRP did not relate to FMD or GTN at baseline or at intervals over 8 wk in T1DM. Hs-CRP did not change over time. In T1DM, but not healthy controls, Hs-CRP related to body mass index (BMI) z-score (r = 0.47, p < 0.001), weight z-score (r = 0.41, p < 0.001), and female sex (p = 0.008).

CONCLUSIONS

Hs-CRP is not associated with early vascular dysfunction in children with T1DM. However, in children and adolescents with T1DM, Hs-CRP was associated with female sex and children with higher BMI, suggesting that these groups may be at greater cardiovascular risk. Maintenance of a healthy BMI may be important in the prevention of vascular disease of T1DM.

Diabetes classification: grey zones, sound and smoke: Action LADA 1

Diseases gain identity from clinical phenotype as well as genetic and environmental aetiology. The definition of type 1 diabetes is clinically exclusive, comprising patients who are considered insulin dependent at diagnosis, whilst the definition of type 2 diabetes is inclusive, only excluding those who are initially insulin dependent. Ketosis-prone diabetes (KPD) and latent autoimmune diabetes in adults (LADA) are each exclusive forms of diabetes which are, at least initially, clinically distinct from type 2 diabetes and type 1 diabetes, and each have a different natural history from these major types of diabetes.KPD can be diagnosed unequivocally as diabetes presenting with the categorical clinical feature, ketoacidosis. In contrast, LADA can be diagnosed by the co-occurrence of three traits, not one of which is categorical or exclusive to the condition: adult-onset non-insulin-requiring diabetes, an islet autoantibody such as glutamic acid decarboxylase autoantibodies (GADA) or cytoplasmic islet cell autoantibodies (ICA), and no need for insulin treatment for several months post-diagnosis. But while some would split diabetes into distinct subtypes, there is a strong case that these subtypes form a continuum of varying severity of immune and metabolic dysfunction modified by genetic and non-genetic factors. This article discusses the nature of disease classification in general, and KPD and LADA in particular, emphasizing the potential value and pitfalls in classifying diabetes and suggesting a need for more research in this area.

Atherogenic vascular and lipid phenotypes in young patients with Type 1 diabetes are associated with diabetes high-risk HLA genotype

Expression of human leukocyte antigen (HLA) class II molecules on islet endothelial cells is a central vascular event in the pathogenesis of Type 1 diabetes. Previous studies demonstrated the ability of other vascular endothelial cells to express HLA and thereby to process islet autoantigens on their surface. We investigated whether the HLA-DQ2/8 genotype, which confers the highest risk for Type 1 diabetes, is associated with early atherosclerosis in youths with this disease. Brachial artery endothelium-dependent, flow-mediated dilation (BA-FMD) and carotid artery intima-media thickness (CA-IMT), as well as markers of systemic inflammation [C-reactive protein (CRP), fibrinogen, and orosomucoid], HbA(1C), LDL, HDL, and total cholesterol, were assessed in 86 children and adolescents with Type 1 diabetes (mean age and diabetes duration, 15 and 7 yr, respectively) between 2004 and 2006. HLA genotypes were determined in dried blood spots by an oligoblot hybridization method. As a result, HLA-DQ2/8 was detected in 34 patients (DQ2/8). When this group was compared with the remaining patients (non-DQ2/8, n = 52), there were no differences in age, diabetes duration, HbA(1C), body mass index, inflammatory markers, and IMT (P > or = 0.4). In the DQ2/8 group, LDL-to-HDL ratio was elevated compared with that in the non-DQ2/8 group (1.8 vs. 1.3, respectively; P = 0.001), whereas FMD did not significantly differ between the groups (5.3% vs. 6.7%, respectively; P = 0.08). When patients were further categorized in relation to CRP (cut-off value, 1 mg/l), BA-FMD was significantly lower (3%, P < 0.01), whereas LDL-to-HDL ratio increased further (2.2, P < 0.001) in the subgroup of DQ2/8 and CRP > or = 1 patients compared with the remaining three subgroups. These associations remained significant after adjustment for age, diabetes duration, and HbA(1C) by analysis of covariance. The brachial artery responses to nitroglycerine were similar in all subgroups. In conclusion, the diabetes-predisposing HLA-DQ2/8 genotype in children and adolescents with Type 1 diabetes interferes with endothelial and lipid-related mechanisms of early atherosclerosis, possibly in part through inflammatory pathways.