Association between Serum Cystatin C and Vascular Complications in Type 2 Diabetes Mellitus without Nephropathy

BackgroundRecent studies have correlated serum cystatin C (CysC) with vascular complications, but few studies have investigated this correlation in diabetes patients without nephropathy. This study aimed to evaluate if higher serum CysC levels increase the risk for vascular complications in type 2 diabetes mellitus patients with normal renal function or mild renal impairment.MethodsA total of 806 consecutive patients with type 2 diabetes mellitus who were admitted to the diabetes center of Soonchunhyang University Hospital for blood glucose control were retrospectively reviewed. Patients with nephropathy were excluded. Subjects were categorized into quartiles of serum CysC levels (Q1, ≤0.65 mg/L; Q2, 0.66 to 0.79 mg/L; Q3, 0.80 to 0.94 mg/L; and Q4, ≥0.95 mg/L).ResultsThe proportion of patients with diabetic retinopathy (DR) (P for trend <0.001), coronary heart disease (CHD) (P for trend <0.001), and stroke (P for trend <0.001) increased across the serum CysC quartiles. After adjustment for confounding factors, the highest serum CysC level remained a significant risk factor for DR (odds ratio [OR], 1.929; 95% confidence interval [CI], 1.007 to 4.144; P=0.040). Compared with Q1, a significant positive association was observed between serum CysC and CHD in Q2 (OR, 7.321; 95% CI, 1.114 to 48.114; P=0.012), Q3 (OR, 6.027; 95% CI, 0.952 to 38.161; P=0.020), and Q4 (OR, 8.122; 95% CI, 1.258 to 52.453; P=0.007). No associations were observed between CysC and stroke after additional adjustment for confounding variables.ConclusionSerum CysC levels are independently associated with DR and CHD, suggesting that CysC may be useful for identifying type 2 diabetes mellitus patients without nephropathy who are at high risk for vascular complications

Association of free thyroxine with obstructive lung pattern in euthyroid middle-aged subjects: A population-based study.

BackgroundThe association between thyroid hormone levels and pulmonary function in euthyroid population is still unclear. We aimed to examine the relationship between thyroid function and lung function in a large cohort study of euthyroid subjects.MethodsWe analyzed biochemical and spirometry data from a nationwide, population-based, cross-sectional survey (KNHANES VI). A total of 1,261 middle-aged participants aged 45-65 years with spirometry tests and normal thyroid function were included in this study. The subjects were grouped according to free thyroxine (fT4) (ng/dL) quartiles (Q1, 0.89-1.09; Q2, 1.10-1.19; Q3, 1.20-1.30; Q4, 1.31-1.76). Obstructive lung pattern was defined as forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ResultsOverall, 10.9% of the subjects had an obstructive lung pattern. The mean fT4 levels were significantly higher in those with obstructive lung pattern than in those with normal lung function (1.26 vs. 1.20 ng/dL, pConclusionHigh fT4 levels are an independent predictor of obstructive lung pattern in euthyroid middle-aged subjects. Further prospective studies are needed to confirm these findings

Risk of carotid plaques according to triglyceride-glucose index stratified by thyroid function: A cross-sectional study.

BackgroundRecent studies have indicated that the triglyceride-glucose (TyG) index or subclinical thyroid dysfunction is associated with carotid plaques, a predictor of cardiovascular disease risk. However, evidence for this association is limited and inconsistent. This study aimed to evaluate the risk of carotid plaques according to TyG index and thyroid function status in the general population.MethodsA total of 2,931 individuals who underwent carotid ultrasound as part of a comprehensive health examination at the Health Promotion Center of Soonchunhyang University Hospital were retrospectively reviewed. Based on the TyG index and thyroid function status, the participants were divided into six groups: LoTyG-SHyper (low TyG index with subclinical hyperthyroidism), LoTyG-Eu (low TyG index with euthyroidism), LoTyG-SHypo (low TyG index with subclinical hypothyroidism), HiTyG-SHyper (high TyG index with subclinical hyperthyroidism), HiTyG-Eu (high TyG index with euthyroidism), and HiTyG-SHypo (high TyG index with subclinical hypothyroidism). A multivariate logistic regression analysis was conducted to determine the risk of carotid plaques.ResultsThe proportion of participants with significant carotid plaques was significantly different among the six groups (pConclusionThe TyG index and thyroid function status are important predictors of the risk of carotid plaques in healthy individuals. Early evaluation of carotid plaques may be necessary for subjects with high insulin resistance and subclinical hypothyroidism

Effect of bariatric surgery on circulating and urinary mitochondrial DNA copy numbers in obesity with or without diabetes

Introduction Recent studies have suggested that extracellular circulating and urinary mitochondrial DNA (mtDNA) are associated with mitochondrial dysfunction in obesity and type 2 diabetes mellitus (T2DM). However, the changes to cell-free serum and urinary mtDNA after bariatric surgery in patients with obesity with T2DM have not been investigated to date.Research design and methods We prospectively recruited patients with obesity (n=18), and with obesity and T2DM (n=14) who underwent bariatric surgery, along with healthy volunteers (HV) as a control group (n=22). Serum and urinary mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit-1 (mtND-1) and cytochrome-c oxidase 3 (mtCOX-3) copy numbers were measured using quantitative PCR (qPCR). The mtDNA copy numbers of patients with obesity (with and without T2DM) were followed up 6 months after surgery.Results The copy numbers of urinary mtND-1 and mtCOX-3 in patients with obesity, with or without T2DM, were higher than those in the HVs. Moreover, urinary mtCOX-3 copy number increased in patients with obesity with T2DM compared with patients with obesity without T2DM (p=0.018). Meanwhile, serum mtCOX-3 copy numbers in HV were higher in both obesity patient groups (p=0.040). Bariatric surgery reduced urinary mtND-1 and mtCOX-3 copy numbers, as well as serum mtCOX-3 copy numbers only in patients with obesity with T2DM.Conclusion These results suggest that T2DM induces greater kidney mitochondrial dysfunction in patients with obesity, which can be effectively restored with bariatric surgery

Triiodothyronine Levels Are Independently Associated with Metabolic Syndrome in Euthyroid Middle-Aged Subjects

BackgroundRecent studies have shown an association between thyroid hormone levels and metabolic syndrome (MetS) among euthyroid individuals; however, there have been some inconsistencies between studies. Here, we evaluated the relationship between thyroid hormone levels and MetS in euthyroid middle-aged subjects in a large cohort.MethodsA retrospective analysis of 13,496 euthyroid middle-aged subjects who participated in comprehensive health examinations was performed. Subjects were grouped according to thyroid stimulating hormone, total triiodothyronine (T3), total thyroxine (T4), and T3-to-T4 ratio quartile categories. We estimated the odds ratios (ORs) for MetS according to thyroid hormone quartiles using logistic regression models, adjusted for potential confounders.ResultsOf the study patients, 12% (n=1,664) had MetS. A higher T3 level and T3-to-T4 ratio were associated with unfavourable metabolic profiles, such as higher body mass index, systolic and diastolic blood pressure, triglycerides, fasting glucose and glycated hemoglobin, and lower high density lipoprotein cholesterol levels. The proportion of participants with MetS increased across the T3 quartile categories (P for trend <0.001) and the T3-to-T4 ratio quartile categories (P for trend <0.001). The multi-variate-adjusted OR (95% confidence interval) for MetS in the highest T3 quartile group was 1.249 (1.020 to 1.529) compared to the lowest T3 quartile group, and that in the highest T3-to-T4 ratio quartile group was 1.458 (1.141 to 1.863) compared to the lowest T3-to-T4 ratio quartile group, even after adjustment for potential confounders.ConclusionSerum T3 levels and T3-to-T4 ratio are independently associated with MetS in euthyroid middle-aged subjects. Longitudinal studies are needed to define this association and its potential health implications