Serum cystatin C is independently associated with aortic arterial stiffness in patients with type 2 diabetes

Serum Cystatin C is Associated with Peripheral Artery Stiffness in Patients with Type 2 Diabetes Mellitus Combined with Chronic Kidney Disease

OBJECTIVE

Cystatin C (CysC) is associated with arterial stiffness. However, its suitability for evaluating patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD) remains unclear. We aimed to investigate the relationship between CysC levels and peripheral arterial stiffness (PAS) in patients with T2DM combined with CKD.

METHODS

Participants' arterial stiffness was assessed using brachial-ankle pulse wave velocity (baPWV), and those with a baPWV ≥ 1800 cm/s were included in the PAS group. Additionally, patients were divided into young (18-44 years old), middle-aged (45-59 years old), and older (≥ 60 years old) groups.

RESULTS

Of 200 patients, 94 (47%) were diagnosed with PAS. Multivariate logistic regression revealed that age, pulse pressure, and CysC levels (odds ratio = 1.525, 95% confidence interval: 1.072-2.168, P = 0.019) were independently correlated with PAS in patients with T2DM combined with CKD. The levels of CysC in different age groups were positively correlated with baPWV, and the correlation was significantly higher in the young group (r = 0.739, P < 0.001) than in the middle-aged (r = 0.329, P < 0.001) and older (r = 0.496, P < 0.001) groups. The multifactor linear regression analysis revealed that CysC was significantly correlated with baPWV in the young group (β = 0.455, P = 0.002).

CONCLUSION

CysC was an independent predictor of PAS in patients with T2DM combined with CKD and was more significantly associated with baPWV in young patients than in middle-aged and older patients. CysC may may be an early predictor of peripheral arteriosclerosis in patients with T2DM combined with CKD.

Serum adipocyte fatty acid-binding protein level is positively associated with aortic stiffness in nondialysis chronic kidney disease patients: A cross-sectional study

Aortic stiffness (AS) is a major predictor of cardiovascular disease and mortality in patients with chronic kidney disease (CKD) and adipocyte fatty acid-binding protein (A-FABP) is a novel adipokine that is positively correlated with AS in the general population. Therefore, we investigated the correlation between serum A-FABP levels and AS in nondialysis CKD patients. Fasting blood samples and baseline characteristics were obtained in 270 patients with nondialysis CKD. Serum A-FABP concentrations were determined by enzyme immunoassay and carotid-femoral pulse wave velocity (cfPWV) measurements were acquired using a validated tonometry system. Patients with cfPWV >10 m/s formed the AS group, while those with values ≤10 m/s comprised the comparison group. Among 270 CKD patients, 92 patients (34.1%) were in the AS group. Compared to those in the comparison group, patients in the AS group were older (P < .001), had a higher prevalence of diabetes, along with higher serum A-FABP level (P < .001), larger waist circumference (P = .004), and lower estimated glomerular filtration rate (P = .001) but higher levels of body fat mass (P = .010), systolic blood pressure (P < .001), fasting glucose (P = .014), blood urea nitrogen (P = .009), and serum creatinine (P = .004). The serum log-A-FABP level was positively associated with log-cfPWV (β = 0.178, P = .001) in nondialysis CKD patients and multivariable logistic regression analysis identified serum A-FABP (P = .006), age (P = .001), and systolic blood pressure (P = .015) as independent predictors of AS in nondialysis-dependent CKD patients. Elevated A-FABP levels may be a significant predictor of AS in nondialysis CKD patients.

Increased serum cystatin C levels and responses of pancreatic α- and β-cells in type 2 diabetes

BACKGROUND

Increased serum cystatin C (CysC) can predict the onset of type 2 diabetes (T2D). Meanwhile, impaired pancreatic α- and β-cell functions get involved in the pathophysiological processes of T2D. So this study was to explore the relationships between serum CysC levels and pancreatic α- and β-cell functions in T2D.

METHODS

In this cross-sectional observational study, a total of 2634 patients with T2D were consecutively recruited. Each recruited patient received a serum CysC test and oral glucose tolerance test for synchronous detection of serum C-peptide and plasma glucagon. As components of pancreatic β-cell function, insulin secretion and sensitivity indices were evaluated by C-peptide area under the curve (AUC-CP) and C-peptide-substituted Matsuda's index (Matsuda-CP), respectively. Fasting glucagon (F-GLA) and post-challenge glucagon calculated by glucagon area under the curve (AUC-GLA) were used to assess pancreatic α-cell function. These skewed indices and were further natural log-transformed (ln).

RESULTS

With quartiles of serum CysC levels ascending, AUC-CP, F-GLA and AUC-GLA were increased, while Matsuda-CP was decreased (P for trend <0.001). Moreover, serum CysC levels were positively related to lnAUC-CP, lnF-GLA and lnAUC-GLA (r= 0.241, 0.131 and 0.208, respectively, P < 0.001), and inversely related to lnMatsuda-CP (r= -0.195, P < 0.001). Furthermore, after controlling for other relevant variables via multivariable linear regression analysis, serum CysC levels were identified to account for lnAUC-CP (β= 0.178, t= 10.518, P < 0.001), lnMatsuda-CP (β= -0.137, t= -7.118, P < 0.001), lnF-GLA (β= 0.049, t= 2.263, P = 0.024) and lnAUC-GLA (β= 0.121, t= 5.730, P < 0.001).

CONCLUSIONS

Increased serum CysC levels may be partly responsible for increased insulin secretion from β-cells, decreased systemic insulin sensitivity, and elevated fasting and postprandial glucagon secretion from α-cells in T2D.

Negative Correlation of Serum Adiponectin Level with Aortic Stiffness in Elderly Diabetic Persons

Adiponectin has anti-inflammatory activity against atherosclerosis. Aortic stiffness is a common manifestation of atherosclerosis in diabetes mellitus and elderly persons. This study aimed to evaluate whether low serum adiponectin levels were associated with aortic stiffness in geriatric diabetic patients. Blood samples were obtained from 130 diabetic participants aged ≥ 65 years. We defined high aortic stiffness based on a carotid−femoral pulse wave velocity (cfPWV) of >10 m/s. Circulating adiponectin concentrations were examined using enzyme-linked immunosorbent assays. Sixty-six participants (50.8%) had aortic stiffness. Patients with aortic stiffness had lower serum adiponectin concentrations than those in the control group (p < 0.001). Multivariate logistic regression analysis showed that the adiponectin level (odds ratio: 0.939, 95% confidence interval: 0.898−0.981, p = 0.005) was an independent predictor of aortic stiffness in elderly diabetic persons. Multivariate forward stepwise linear regression analysis also demonstrated that the adiponectin level (β = −0.256, adjusted R2 change = 0.100, p = 0.003) was negatively associated with cfPWV values in older diabetic patients. In conclusion, serum adiponectin is negatively correlated with cfPWV and is an independent predictor of aortic stiffness in elderly diabetic persons.

Serum Levels of Fibroblast Growth Factor 21 Are Positively Associated with Aortic Stiffness in Patients with Type 2 Diabetes Mellitus

Aortic stiffness (AS), assessed using carotid–femoral pulse wave velocity (cfPWV), is associated with cardiovascular disease in type 2 diabetes mellitus (T2DM). The relationship between serum fibroblast growth factor 21 (FGF-21) and AS in T2DM patients was evaluated. Fasting serum FGF-21 levels of 130 T2DM patients were measured using an enzyme immunoassay kit. A validated tonometry system was used to measure cfPWV (>10 m/s indicated AS). Of these T2DM patients, 34.6% were defined as the AS group. T2DM patients with AS were older; exhibited higher systolic blood pressure, diastolic blood pressure, and body fat mass; higher triglyceride, fasting glucose, glycosylated hemoglobin, and creatinine levels; higher urine albumin-to-creatinine ratios and serum FGF-21 levels; and lower estimated glomerular filtration rates. The FGF-21 level (odds ratio = 1.005, 95% confidence interval: 1.002–1.009, p = 0.002) as well as systolic blood pressure was an independent predictor of AS and positively correlated to cfPWV values (β = 0.369, p < 0.001) in T2DM patients. For T2DM patients, serum FGF-21 level could be a predictor for AS.

Decreased Physiological Serum Total Bile Acid Concentrations in Patients with Type 2 Diabetic Peripheral Neuropathy

PURPOSE

Bile acids, amphipathic cholesterol metabolites, have been reported to have cytoprotective and neuroprotective effects in humans and animal models. The relationship of physiological serum total bile acid (TBA) levels with diabetic peripheral neuropathy (DPN), however, has not been determined. The purpose of this study was to investigate the relationship between physiological serum TBA and DPN.

PATIENTS AND METHODS

In total, 856 patients with type 2 diabetes mellitus (T2DM) aged 20-89 years were enrolled in this cross-sectional study. Serum TBA was measured, and its relationship with DPN and other parameters was analyzed.

RESULTS

T2DM patients with DPN had significantly lower serum TBA compared with those without (P<0.01). Serum TBA was negatively associated with glycated hemoglobin A1C, plateletcrit, fibrinogen, urine albumin-to-creatinine ratio, vibration perception thresholds, and prevalence of DPN, peripheral arterial disease, and diabetic foot ulceration after adjustment for age, sex, and body mass index (P<0.01 or P<0.05). A graded association with prevalence of DPN and increase in serum TBA quartiles was observed (P for trend <0.01), and there was an 48.2% decreased risk of DPN in the highest quartile of serum TBA versus the lowest quartile (95% CI 0.299-0.617; P=0.000) after multivariate adjustment. Receiver-operating characteristic analysis revealed that the optimal cutoff point of serum TBA to indicate DPN was 2.85 μmol/L (sensitivity 77.6% and specificity 45.6%).

CONCLUSION

These findings suggest that lower physiological serum TBA level may be associated with the prevalence of DPN in T2DM patients and may be a potential biomarker for DPN.

Association of Low Serum Adiponectin Levels with Aortic Arterial Stiffness in Patients with Type 2 Diabetes

Adiponectin, an anti-inflammatory and anti-atherogenic protein, affects glucose metabolism. High serum adiponectin levels are associated with decreased diabetes mellitus (DM) risks. Aortic arterial stiffness (AS) is associated with cardiovascular disease and mortality in type 2 DM patients. We assessed the association between adiponectin levels and aortic AS in type 2 DM patients. We measured serum adiponectin levels in 140 volunteers with type 2 DM and assigned patients with carotid–femoral pulse wave velocity (cfPWV) >10 m/s to the aortic AS group (n = 54, 38.6%). These patients had higher systolic (p = 0.001) and diastolic (p = 0.010) blood pressures; body fat masses (p = 0.041); serum triglyceride (p = 0.026), phosphorus (p = 0.037), and insulin (p = 0.040) levels; and homeostasis model assessment of insulin resistance values (p = 0.029) and lower estimated glomerular filtration rates (p = 0.009) and serum adiponectin levels (p = 0.001) than controls. Multivariable logistic regression analysis adjusted for confounders showed serum adiponectin levels (OR 0.922; 95% CI, 0.876–0.970; p = 0.002) as an independent predictor of aortic AS. Multivariable forward stepwise linear regression analyses showed that serum adiponectin levels (β = −0.283, adjusted R² change: 0.054, p < 0.001) were negatively associated with cfPWV. Thus, serum adiponectin level is an independent predictor of aortic AS in type 2 DM patients.

High serum adipocyte fatty acid binding protein concentration linked with increased aortic arterial stiffness in patients with type 2 diabetes

BACKGROUND

Adipocyte fatty acid binding protein (A-FABP) is a novel adipokine that contributes to the development of metabolic disorder, type 2 diabetes mellitus (T2DM) and atherosclerosis. We determined the correlation between serum A-FABP and aortic stiffness in T2DM patients.

METHODS

Fasting blood samples were obtained from 156 patients with T2DM. Serum A-FABP concentration were determined using a commercial enzyme immunoassay. Carotid-femoral pulse wave velocity (cfPWV) was measured using SphygmoCor System, and cfPWV values of >10 m/s were defined as high aortic stiffness.

RESULTS

Sixty participants (38.4%) fell under the high aortic stiffness group. This group, compared to the control group, showed older age (P = .004), higher systolic blood pressure (P < .001), diastolic blood pressure (P = .027), urine albumin-to-creatinine ratio (P = .003), serum A-FABP (P < .001) and lower estimated glomerular filtration rate (P = .001). After adjusting for factors significantly associated with aortic stiffness using multivariable logistic regression analysis, serum A-FABP [OR = 1.029 (1.002-1.058), P = .039] was found to be an independent predictor of aortic stiffness in T2DM patients.

CONCLUSIONS

Serum A-FABP is positively correlated with aortic arterial stiffness in patients with T2DM.