Higher intake of fruits,vegetables or their fiber reduces the risk of type 2 diabetes: A meta‐analysis

Aims/Introduction

Some previous studies reported no significant association of consuming fruit or vegetables, or fruit and vegetables combined, with type 2 diabetes. Others reported that only a greater intake of green leafy vegetables reduced the risk of type 2 diabetes. To further investigate the relationship between them, we carried out a meta‐analysis to estimate the independent effects of the intake of fruit, vegetables and fiber on the risk of type 2 diabetes.

Materials and Methods

Searches of MEDLINE and EMBASE for reports of prospective cohort studies published from 1 January 1966 to 21 July 2014 were carried out, checking reference lists, hand‐searching journals and contacting experts.

Results

The primary analysis included a total of 23 (11 + 12) articles. The pooled maximum‐adjusted relative risk of type 2 diabetes for the highest intake vs the lowest intake were 0.91 (95% confidence interval [CI] 0.87–0.96) for total fruits, 0.75 (95% CI 0.66–0.84) for blueberries, 0.87 (95% CI 0.81–0.93) for green leafy vegetables, 0.72 (95% CI 0.57–0.90) for yellow vegetables, 0.82 (95% CI 0.67–0.99) for cruciferous vegetables and 0.93 (95% CI 0.88–0.99) for fruit fiber in these high‐quality studies in which scores were seven or greater, and 0.87 (95% CI 0.80–0.94) for vegetable fiber in studies with a follow‐up period of 10 years or more.

Conclusions

A higher intake of fruit, especially berries, and green leafy vegetables, yellow vegetables, cruciferous vegetables or their fiber is associated with a lower risk of type 2 diabetes.     

Association of chemokine ligand 5/chemokine receptor 5 gene promoter polymorphisms with diabetic microvascular complications: A meta‐analysis

Aims/Introduction

Chemokine ligand 5 (CCL5) is a member of the CC‐chemokine family expressed in various organs. It contributes to the migration of monocytes/macrophages into injured vascular walls by binding with its receptor chemokine receptor 5 (CCR5). Many studies have accessed the association between CCL5/CCR5 gene promoter polymorphisms and diabetic microvascular complications (DMI). However, the results are conflicting and inconclusive. The aim of the present study was to evaluate the association more precisely.

Materials and Methods

Trials were retrieved through PubMed, Embase, Medline, China National Knowledge Infrastructure, Web of Science and Cochrane database without restrictions on language. The pooled odds ratio (OR) and 95% confidence interval (CI) were used to describe the strength of association with DMI.

Results

Data were obtained from 11 case–control studies that included 2,737 DMI patients and 2,435 diabetic control subjects. In the overall analysis, the CCL5‐403 G/A and CCL5‐28 C/G gene polymorphisms were not significantly associated with the risk of DMI. However, CCR5‐59029 G/A was an independent risk factor of DMI in a dominant model (OR 1.77, 95% CI 1.06–2.97). Subgroup analysis showed that the risk of the CCR5 59029A‐positive genotype was significant in Asians (OR 2.08, 95% CI 1.68–2.57). In addition, the CCR5 59029A‐positive genotype was associated with increased risk of albuminuria.

Conclusions

There were no associations of CCL5 gene promoter polymorphism with the risk of DMI. However, the 59029A polymorphism in CCR5 might affect individual susceptibility for DMI.     

Age‐associated changes of islet endocrine cells and the effects of body mass index in Japanese

Aims/Introduction

Impaired growth and premature death of β‐cells are implicated in the progression of islet pathology in type 2 diabetes. It remains unclear, however, how aging affects islet cells, or whether the islet change in diabetes is an augmented process of aging. We studied age‐related changes of the islet structure in Japanese non‐diabetic subjects and explored the underlying mechanism of the changes.

Materials and Methods

A total of 115 non‐diabetic autopsy cases were subjected to morphometric analysis for volume densities of islets, β‐ and non‐β‐cells, as well as their masses. Proliferation activity identified by Ki67, and expressions of pancreatic and duodenal homeobox (PDX)‐1, cell cycle inhibitor P16, and oxidative stress marker γH2AX were also examined.

Results

There was a gradual and marginal decline of volume densities of islets, β‐ and non‐β‐cells with aging, while masses of these components were increased during maturation and slowly decreased after the 40s. Islet density was high in the young, but reduced after maturation. There was only a minimal influence of increased body mass index (BMI) on the increase in β‐cell mass, but not on the other variables. Ki67 positivity and PDX‐1 expressions were high in the young, but low after maturation, whereas expressions of P16 and γH2AX were elevated in the aged.

Conclusions

Age‐associated decline of β‐cell mass is marginal after maturation, and the reduction of β‐cell mass could be a specific process in diabetes. The impact of BMI on the islet structure is limited in Japanese with normal glucose tolerance.     

Replication study for the association of rs391300 in SRR and rs17584499 in PTPRD with susceptibility to type 2 diabetes in a Japanese population

Aims/Introduction

Genetic risk variants for type 2 diabetes; rs391300‐G in SRR and rs17584499‐T in PTPRD, have been identified by a genome‐wide association study using Han Chinese individuals living in Taiwan. In an attempt to know the effects of these two variants in conferring susceptibility to type 2 diabetes in the Japanese, we carried out a replication study for the association of the two single nucleotide polymorphisms (SNPs) with type 2 diabetes in a Japanese population.

Materials and Methods

We genotyped 11,530 Japanese individuals (8,552 type 2 diabetes patients and 2,978 controls) for rs391300 and rs17584499, and analyzed the association of these two SNPs with type 2 diabetes by logistic regression analysis.

Results

Neither of the variants was associated with susceptibility to type 2 diabetes in the Japanese population (rs391300‐G: odds ratio [OR] = 0.97; 95% confidence interval [CI] 0.91–1.04; P = 0.44; rs17584499‐T: OR = 1.04; 95% CI 0.96–1.14; P = 0.34). Adjustment or stratified analysis for age, sex and body mass index (BMI) did not affect the association of these variants with the disease. We did not observe a significant association of the SNPs with any metabolic traits, BMI, fasting plasma glucose, homeostasis model assessment of β‐cell function (HOMA‐β) and HOMA of insulin resistance (HOMA‐IR) (P > 0.05).

Conclusions

Neither rs391300 nor rs17584499 had a significant effect on conferring susceptibility to type 2 diabetes in the Japanese population.     

Circulating cell‐free mitochondrial deoxyribonucleic acid is increased in coronary heart disease patients with diabetes mellitus

Aims/Introduction

Circulating cell‐free mitochondrial deoxyribonucleic acid (ccf‐mtDNA) is presumably derived from injured tissues or cells in the body and has been suggested to be potential biomarker in several diseases. The present study explored whether mtDNA could be used as a biomarker to evaluate disease in coronary heart disease (CHD) patients with or without diabetes mellitus (DM).

Materials and Methods

A total of 50 CHD patients with type 2 diabetes, 50 CHD patients without type 2 diabetes, and 50 age‐ and sex‐matched patients without CHD and DM (non‐CHD‐DM) were recruited. Ccf‐mtDNA levels were assessed by measuring the nicotinamide adenine dinucleotide dehydrogenase 1 gene using quantitative real‐time polymerase chain reaction. Receiver operating characteristic curve analysis of plasma mtDNA in CHD with or without DM was also determined. Multivariate logistic regression analyses were carried out to determine the correlation between the mtDNA levels and traditional CHD risk factors.

Results

The plasma ccf‐mtDNA levels were significantly elevated in CHD patients with DM compared with those without and non‐CHD‐DM. The area under the receiver operating characteristic curves of mtDNA in CHD patients with DM vs non‐CHD‐DM was 0.907%. Correlation analyses of the mtDNA levels and traditional CHD risk factors showed that the mtDNA levels were significantly correlated with fasting blood glucose in CHD patients with DM.

Conclusions

Ccf‐mtDNA levels can be used as a biomarker in CHD patients with DM.     

Risk of hospitalization for diabetic macrovascular complications and in‐hospital mortality with irregular physician visits using propensity score matching

Aims/Introduction

The objective of the present study was to evaluate the risk of diabetic macrovascular complications and in‐hospital mortality among diabetic patients with irregular physician visits.

Materials and Methods

We carried out a health insurance‐based retrospective cohort study using claims data from diabetic patients who were newly hospitalized between April 2010 and September 2010 among beneficiaries of the Fukuoka National Health Insurance Organization. Regular visits were defined as physician visits for diabetes mellitus at least every 3 months between April 2009 and March 2010, whereas other visits or no visits were defined as irregular visits. We assigned 5,940 patients to the regular visit or the irregular visit groups using propensity score matching. We compared in‐hospital mortality and hospitalization for diabetic macrovascular complications between the two groups by multiple logistic regression models.

Results

The irregular visit group had a significantly higher risk of hospitalization for acute myocardial infarction (AMI), ischemic heart diseases (IHDs) except AMI, all IHDs, all strokes and diabetic macrovascular complications than did the regular visit group. Adjusted odds ratios for AMI, IHDs except AMI, all IHDs, all strokes, and diabetic macrovascular complications were 3.52 (95% confidence interval [CI] 1.79–6.96), 1.25 (95% CI 1.02–1.54), 1.37 (95% CI 1.12–1.66), 1.29 (95% CI 1.04–1.60), and 1.28 (95% CI 1.10–1.48), respectively.

Conclusions

The present study shows that the irregular visit group had significantly higher risks of hospitalization for IHD and stroke among diabetic patients. Insurers need to motivate diabetic beneficiaries to make regular visits to physicians.     

Association of salivary alpha 2‐macroglobulin levels and clinical characteristics in type 2 diabetes

Aims/Introduction

Studies suggest that salivary proteins can be used as potential non‐invasive markers for clinical diagnosis and screening for diabetes. Previous reports showed that plasma alpha 2‐macroglobulin (A2MG) levels were higher in diabetic patients, especially with diabetic complications. We investigated the relationship between salivary A2MG values and clinical characteristics in patients with type 2 diabetes.

Materials and Methods

A total of 91 adults were recruited from our outpatient clinics. The study the patients'' collected general and biochemical data, and blood glucose (fasting glucose, glycated hemoglobin [HbA1c]) data. Plasma and salivary A2MG levels were examined by enzyme‐linked immunosorbent assay.

Results

The salivary A2MG levels were significantly positively correlated with plasma A2MG levels, fasting glucose HbA1c and periodontitis status. After 3 months of follow up, the net change of salivary A2MG values positively correlated with the net change of fasting glucose, HbA1c and triglyceride levels, but negatively correlated with high‐density lipoprotein cholesterol changes. Furthermore, the correlations between salivary A2MG and fasting glucose HbA1c were better than plasma A2MG, respectively.

Conclusions

Our data show that salivary A2MG levels have better correlation with fasting glucose HbA1c and periodontitis status than plasma A2MG in diabetic patients. Salivary A2MG concentration might serve as a non‐invasive marker for clinical diabetic control.     

Impact of cigarette smoking on impaired insulin secretion and insulin resistance in Japanese men: The Saku Study

Aims/Introduction

To assess the impact of smoking on impaired insulin secretion and insulin resistance in Japanese men.

Materials and Methods

This study included 1,199 men aged 30–79 years without diabetes, impaired insulin secretion and insulin resistance at baseline who underwent a comprehensive medical check‐up between April 2006 and March 2007 at Saku Central Hospital. Smoking status was categorized as current, ex‐smoker and never‐smoker. Insulinogenic index and homeostasis model assessment‐insulin resistance were determined using a standard 75‐g oral glucose tolerance test. The Japan Diabetes Society criteria were used to define impaired insulin secretion and insulin resistance. Participants were followed up until March 2011.

Results

A total of 449 and 99 men developed impaired insulin secretion and insulin resistance during 3,403 and 4,092 person‐years follow up, respectively. The multivariable‐adjusted hazard ratios (HRs) for impaired insulin secretion were 1.06 (95% confidence interval [CI] 0.84–1.33) in ex‐smokers and 1.95 (95% CI 1.44–2.63) in current smokers compared with never‐smokers after adjustment for age, familial history of diabetes, alcohol consumption, exercise, systolic blood pressure, triglyceride, γ‐glutamyltransferase, waist circumference, leukocyte count, changes in smoking status and changes in waist circumference. The number of pack‐years was positively associated with the risk for impaired insulin secretion in a dose‐dependent manner (P‐values for trend <0.001). The multivariable‐adjusted HRs for insulin resistance were 0.95 (95% CI 0.56–1.61) in ex‐smokers and 1.11 (95% CI 0.67–1.79) in current smokers compared with never‐smokers.

Conclusions

Cigarette smoking is a modifiable risk factor for impaired insulin secretion. The findings might also be important for other Asian populations, which have low insulin secreting ability.     

Effects of soybean product intake on fasting and postload hyperglycemia and type 2 diabetes in Japanese men with high body mass index: The Saku Study

Aims/Introduction

The inverse association between soybean intake and type 2 diabetes mellitus has been reported. We investigated the effects of soybean product intake on the incidence of type 2 diabetes mellitus considering fasting and postload hyperglycemia.

Materials and Methods

The present 4‐year, cohort study included 1,738 men and 1,301 women, aged 30–69 years, without diabetes mellitus at baseline who underwent comprehensive medical check‐ups between April 2006 and March 2007 at Saku Central Hospital. Participants were stratified by sex and body mass index (BMI), and further classified into three groups based on soybean product intake: group 1 (0–1 time/week), group 2 (2–3 times/week) and group 3 (four or more times per week). Participants underwent annual standard 75‐g oral glucose tolerance testing during follow‐up periods until March 2011. Main outcomes were incidence of fasting hyperglycemia, postload hyperglycemia and type 2 diabetes mellitus.

Results

During 10,503 person‐years of follow up, 204 participants developed type 2 diabetes mellitus, including 61 who developed fasting hyperglycemia and 147 who developed postload hyperglycemia. Among men with a high BMI, group 3 had significantly lower risk for the incidence of type 2 diabetes mellitus, fasting hyperglycemia and postload hyperglycemia than group 1, and multivariable‐adjusted hazard ratios and 95% confidence intervals were 0.44 (0.22–0.89), 0.36 (0.15–0.96) and 0.40 (0.18–0.92), respectively. Similar results were not observed among men with low BMI or women.

Conclusions

Soybean product intake prevented fasting and postload hyperglycemia and type 2 diabetes mellitus in men with a high BMI. Further long‐term observation is necessary.     

Prevalence of retinopathy and its risk factors in a Japanese population

Aims/Introduction

To determine the prevalence and risk factors of retinopathy and validity of the current diagnostic cut‐offs for diabetes by using data of health check‐up examinees.

Materials and Methods

The study comprises 1,864 Japanese who participated in the general health check‐up program and did not have a previous history of cardiovascular disease. Non‐mydriatic 45° digital fundus photographs were taken twice annually. Multivariate logistic regression model was used to identify risk factors for retinopathy in participants without previously diagnosed diabetes.

Results

The overall prevalence of retinopathy in participants with and without previously diagnosed diabetes were 23.3% (28/120) and 4.2% (74/1,744), respectively. Univariate logistic regression analysis identified age, systolic blood pressure (SBP), fasting plasma glucose (FPG) and hemoglobin A1c (HbA_1c) as risk factors for retinopathy. Multivariate logistic regression analysis showed that FPG or both HbA_1c and SBP were significant, positive and independent risk factors for retinopathy. The prevalence of retinopathy increased with deterioration of glucose categories (P < 0.001 for FPG or HbA_1c). However, a statistically significant increased risk of retinopathy remained only in participants with FPG ≥ 7.0 mmol/L or HbA1c ≥ 6.5% compared with those with the lowest quartile of glucose in the participants without previously diagnosed diabetes after adjusting for age and SBP.

Conclusions

The prevalence of retinopathy was 4.2%, and FPG or both HbA_1c and SBP were positive and independent risk factors for retinopathy in health check‐up examinees without previously diagnosed diabetes. The FPG 7.0 mmol/L or HbA_1c 6.5% seems to be appropriate to diagnose diabetes in view of its association with retinopathy.     

Effect of endurance training on retinol‐binding protein 4 gene expression and its protein level in adipose tissue and the liver in diabetic rats induced by a high‐fat diet and streptozotocin

Aims/Introduction

The present study was designed to investigate from which tissues the decrease in retinol‐binding protein 4 (RBP4) expression could contribute to the improvement of serum RBP4 and insulin resistance (IR) after endurance training.

Materials and Methods

Male 7‐week‐old Wistar rats were randomly assigned into four groups including control (C), trained (T), diabetic control (DC) and trained diabetic (TD). At 8 weeks‐of‐age, diabetes was induced by a high‐fat diet and intraperitoneal injection of low‐dose streptozotocin (STZ; 35 mg/kg). Rats in the T and TD groups carried out a 7‐week exercise program on a motorized treadmill (15–20 m/min for 20 min/day for 5 weeks), whereas the C and DC remained sedentary in their cages. Tissues gene expression and protein levels of RBP4 were assessed by using real‐time polymerase chain reaction and western blot, respectively, while serum RBP4 was measured using an enzyme‐linked immunosorbent assay kit.

Results

Exercise significantly improved IR and reduced serum concentration of RBP4 in the TD group. This reduction of serum RBP4 was accompanied by decreased RBP4 protein expression in visceral fat tissue. In contrast, exercise had no significant effect on RBP4 expression in liver and subcutaneous fat tissue in the TD group. Exercise also significantly decreased RBP4 gene expression in visceral fat tissue and muscle, whereas the effect of exercise on liver RBP4 messenger ribonucleic acid expression was not significant.

Conclusions

The present study showed that the mechanism for RBP4 reducing the effect of endurance training could involve decreased RBP4 messenger ribonucleic acid expression and its protein level in adipose tissue in STZ‐induced diabetic rats.     

Combination therapy with an angiotensin‐converting‐enzyme inhibitor and an angiotensin II receptor antagonist ameliorates microinflammation and oxidative stress in patients with diabetic nephropathy

Aims/Introduction

Recent studies have pointed to the effectiveness of combination therapy with an angiotensin‐converting‐enzyme inhibitor (ACEI) and an angiotensin receptor blocker (ARB) for diabetic nephropathy. However, some controversy over this combination treatment remains and the mechanisms underlying its renoprotective effects have not been fully clarified. Therefore, we compared the renoprotective effects of imidapril (ACEI) and losartan (ARB) combination therapy with losartan monotherapy in patients with diabetic nephropathy. We also compared the anti‐inflammatory and anti‐oxidative stress effects of these two treatments.

Materials and Methods

A total of 32 Japanese patients with type 2 diabetes and nephropathy were enrolled. Patients were randomized to either 100 mg/day losartan (n = 16) or 50 mg/day losartan plus 5 mg/day imidapril (n = 16). We evaluated clinical parameters, serum concentrations of high‐sensitivity C‐reactive protein (hs‐CRP), soluble intercellular adhesion molecule‐1 (sICAM‐1), interleukin‐18 (IL‐18) and monocyte chemotactic protein‐1 (MCP‐1), and the urinary concentrations of IL‐18, MCP‐1 and 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG) at 24 and 48 weeks after starting treatment.

Results

Blood pressure was not significantly different between the two groups. The serum levels of hs‐CRP, sICAM‐1 and IL‐18, as well as urinary excretion of albumin, IL‐18 and 8‐OHdG decreased significantly in the combination therapy group at 48 weeks. The percent decreases in serum IL‐18 concentrations and urinary IL‐18 and 8‐OHdG were significantly greater in the combination therapy group than in the monotherapy group.

Conclusions

Combination therapy with an ACEI and an ARB could be beneficial for treating diabetic nephropathy through its anti‐inflammatory and anti‐oxidative stress effects.     

Significance of renal biopsy in patients with presumed diabetic nephropathy

Aims/Introduction

Patients with diabetic nephropathy (DN) typically show varying degrees of proteinuria and renal impairment. Because these clinical signs are frequently observed in other glomerulopathies, renal biopsy is required to make a definitive diagnosis of DN. We carried out the present study to evaluate the significance of renal biopsy for patients who have been presumptively diagnosed with DN.

Materials and Methods

A total of 55 patients with type 2 diabetes mellitus (DM), and proteinuria, hematuria and/or renal impairment were enrolled in this study.

Results

Renal biopsy showed that just 30 patients (54.5%) were histologically diagnosed with DN. Fasting plasma glucose and glycated hemoglobin levels were associated with the presence of DN, whereas baseline renal function showed no statistically significant relationship to DN. The duration of DM was not associated with the presence of DN. Patients with DN had a higher rate of diabetic retinopathy (DR) than those with non‐DN (DN 18 patients vs non‐DN three patients, P = 0.00029). DN patients with DR showed a more severe renal histology than those without.

Conclusions

These data suggest that, even for patients with long‐term DM, renal biopsy should be carried out in patients with presumed DN. Because treatment options differ between DN and primary glomerulopathies, renal biopsy should especially be considered for presumed DN without DR.     

Influence of atherosclerosis‐related risk factors on serum high‐sensitivity C‐reactive protein levels in patients with type 2 diabetes: Comparison of their influence in obese and non‐obese patients

Aims/Introduction

Increased levels of high‐sensitivity C‐reactive protein (hs‐CRP) likely leads to the development of atherosclerosis. Therefore, it is very important to know which factors largely influence hs‐CRP levels. In the present study, we examined the influence of various atherosclerosis‐related factors on hs‐CRP levels in patients with type 2 diabetes.

Materials and Methods

A total of 275 patients (176 men, 99 women) were enrolled in this study. We tested the relationship between the number of risk factors reaching a desired value and hs‐CRP levels. The Mann–Whitney U‐test was used to compare two groups. The Kruskal–Wallis test was used to carry out overall group comparisons, and the Steel–Dwass test was used to carry out between‐group comparisons. Spearman''s rank correlation was carried out to study the correlation between hs‐CRP levels and clinical parameters. Multivariate regression method was used to analyze the factors independently contributing to hs‐CRP levels.

Results

Hs‐CRP levels were lower in patients with a larger number of risk factors reaching a desired value. In particular, triglyceride and body mass index (BMI) were independent risk factors determining hs‐CRP levels in a multivariate regression analysis. Furthermore, we compared the influence of various factors on hs‐CRP levels in both obese (BMI ≥25 kg/m²) and non‐obese patients with type 2 diabetes (BMI <25 kg/m²). In obese groups, BMI and urinary albumin were independent risk factors determining hs‐CRP levels, whereas triglyceride and statin were independent risk factors in non‐obese patients.

Conclusions

There is some difference in the factors responsible for hs‐CRP levels in obese and non‐obese patients with type 2 diabetes.     

Effect of periodontal treatment on glycemic control of patients with diabetes: A systematic review and meta‐analysis

Aims/Introduction

The aim of the present study was to investigate whether non‐surgical periodontal treatment reduces glycated hemoglobin (HbA_1c) and fasting plasma glucose (FPG) levels in diabetic patients.

Materials and Methods

An electronic search was carried out on MEDLINE (through PubMed interface), EMBASE and the Cochrane Central Register of Controlled Trials. Randomized controlled trials with a minimum of 3 months follow up were included. The risk of bias was assessed for each study. A meta‐analysis was carried out to evaluate the effect of non‐surgical periodontal treatment on HbA_1c and FPG levels. The effect of the adjunctive use of antimicrobials was also assessed.

Results

A total of 15 studies were included. A reduction of −0.38% (95% confidence interval [CI] −0.23 to −0.53) after 3–4 months (P < 0.001) and of −0.31% (95% CI 0.11 to −0.74) after 6 months (P = 0.15) of follow‐up was found for HbA_1c, favoring the treatment group. Similarly, in treated patients, a significantly greater decrease in FPG was observed in respect to control participants. Such difference amounted to −9.01 mg/dL (95% CI −2.24 to −15.78) after 3–4 months (P = 0.009) and −13.62 mg/dL (95% CI 0.45 to −27.69) after 6 months (P = 0.06) from treatment, respectively. In participants treated with adjunctive antimicrobials, a non‐significant increase of HbA_1c was observed 3 months after treatment, whereas FPG decreased by 0.27 mg/dL (95% CI 39.56 to −40.11; P = 0.99).

Conclusions

The meta‐analysis showed that non‐surgical periodontal treatment improves metabolic control in patients with both periodontitis and diabetes.     

Serum adiponectin levels predict the risk of coronary heart disease in Japanese patients with type 2 diabetes

Aims/Introduction

An inverse association between adiponectin and coronary heart disease (CHD) has been found in Caucasians, but it is uncertain whether this association can be extrapolated to the East Asian population. The present study aimed to investigate whether serum adiponectin levels can predict CHD in Japanese patients with type 2 diabetes as observed in Caucasians.

Materials and Methods

This longitudinal study included 504 patients with type 2 diabetes (342 men and 162 women) who were admitted to Sumitomo Hospital between July 2005 and December 2006. We used Cox proportional hazard analysis to estimate the hazard ratio (HR) of CHD associated with serum adiponectin levels at baseline.

Results

During a median follow up of 5.7 years (2177 person‐years), 40 participants had new CHD and 10 had recurrent CHD. After multivariate adjustment, the highest compared with the lowest quartile of serum adiponectin levels had a significantly reduced risk of CHD (hazard ratio [HR] 0.35; 95% confidence interval [CI] 0.13–0.94; P = 0.017). The multivariate adjusted HR for the risk of CHD according to a doubling of adiponectin at baseline was 0.61 (95% CI 0.39–0.97; P = 0.037).

Conclusions

High serum adiponectin levels are significantly associated with a lower risk of CHD in Japanese patients with type 2 diabetes. This association is independent of other well‐known CHD risk factors.     

Increased arterial stiffness is closely associated with hyperglycemia and improved by glycemic control in diabetic patients

Aims/Introduction

Although arteriosclerotic diseases have been reported to be frequently complicated by diabetes mellitus (DM), a detailed relationship between hyperglycemia and arterial stiffness has not been fully clarified. We investigated the influence of hyperglycemia on arterial stiffness using the cardio‐ankle vascular index (CAVI), which is a new method for estimating arterial stiffness.

Materials and Methods

CAVI values of 52 early‐staged DM patients (duration <5 years, no microangiopathies) were compared with those of 43 age‐matched non‐diabetic (NDM) subjects. The association between CAVI and clinical background factors was evaluated. The effect of glycemic improvement on CAVI was examined in 36 DM patients who were hospitalized for 2 weeks to treat hyperglycemia. CAVI and clinical parameters were measured twice during hospitalization and again after 8 weeks. Additionally, we measured CAVI before and 2 h after breakfast in five DM and five NDM subjects.

Results

The CAVI of DM patients was significantly higher than that of NDM subjects. Multiple regression analysis showed that neither hypertension, obesity nor dyslipidemia, but aging and hemoglobin A1c (HbA_1c) were significantly related to CAVI elevation. The CAVI, HbA_1c and total cholesterol (TC) had significantly improved. Improvement of CAVI was significantly associated with HbA_1c improvement. In contrast, no significant association was observed between the improvements of TC and CAVI. CAVI values before and after breakfast did not change significantly.

Conclusions

CAVI elevation seems to be a sensitive arteriosclerotic marker, which is closely associated with hyperglycemia and improved by glycemic control.     

Anthropometric indicators of obesity for identifying cardiometabolic risk factors in a rural Bangladeshi population

Aims/Introduction

The aim of the present study was to evaluate the predictive ability of body mass index (BMI), waist circumference (WC), waist‐to‐hip ratio (WHR), waist‐to‐height ratio (WHtR) and body fat percentages (BF%) for the presence of cardiometabolic risk factors, namely type 2 diabetes (DM), hypertension (HTN), dyslipidemia and metabolic syndrome (MS).

Materials and Methods

A total of 2293 subjects aged ≥20 years from rural Bangladesh were randomly selected in a population‐based, cross‐sectional survey. The association of anthropometric indicators with cardiometabolic risk conditions was assessed by using receiver operating characteristic curve analysis and adjusted odds ratios (ORs) for DM, HTN, dyslipidemia and MS.

Results

Area under the curve cut‐off values showed that the association of WHR, BF% and WC was higher than that for other indices for DM, HTN and MS, respectively, for both sexes, and WHtR for men and WHR for women for dyslipidemia. The ORs were highest for WHR for DM and WC for MS for both sexes, and WHtR for men and WC for women for HTN and dyslipidemia, respectively. The optimal cut‐off values for obesity for the present study in men and women showed BMIs of 22 and 22.8 kg/m², WHRs of 0.93 and 0.87, WHtRs of 0.52 and 0.54, BF% of 21.4 and 32.4%, and WCs of 82 and 81 cm, except for MS, which were 90 for men and 80 for women.

Conclusions

Compared with BMI, measures of central obesity, particularly WHR, WC, WHtR and BF%, showed a better association with obesity‐related cardiometabolic risk factors for both sexes.     

Prevalences of diabetic retinopathy and nephropathy are lower in Korean type 2 diabetic patients with non‐alcoholic fatty liver disease

Aims/Introduction

The associations between non‐alcoholic fatty liver disease (NAFLD) and chronic vascular complications of type 2 diabetes remain uncertain. We assessed the relationships between NAFLD and chronic vascular complications in patients with type 2 diabetes.

Materials and Methods

Patients with type 2 diabetes (n = 929) attending a diabetes clinic of a university hospital were studied retrospectively. Patients who had any clinical evidence of cirrhosis or other causes of chronic liver disease were excluded. Prevalences of chronic microvascular and macrovascular complications were assessed. NAFLD was ascertained by ultrasonography.

Results

The prevalence of NAFLD in patients with type 2 diabetes was 63.3%. The prevalences of diabetic retinopathy and nephropathy were significantly lower in patients with NAFLD than those without NAFLD (33.0 vs 70.2%, P < 0.001; 29.3 vs 37.1%, P = 0.007, respectively), whereas no difference was found in the prevalence of diabetic neuropathy. The prevalence of diabetic macrovascular complications was lower in type 2 diabetic patients with NAFLD than those without NAFLD (9.2 vs 14.7%, P = 0.008). After adjustment for confounding factors, such as age, sex, glycated hemoglobin, fasting serum C‐peptide, diabetic duration, body mass index and hypertension, NAFLD remained significantly associated with a lower odds ratio (OR) of diabetic retinopathy (OR 0.440, 95% confidence interval 0.255–0.757, P = 0.003) and nephropathy, (OR 0.541, 95% confidence interval 0.358–0.817, P = 0.003). In contrast, NAFLD was not significantly associated with macrovascular complications after adjustment for confounding factors.

Conclusions

These results suggest that NAFLD is inversely associated with prevalences of diabetic retinopathy and nephropathy in Korean patients with type 2 diabetes.     

Combined effects of physiologically relevant disturbed wall shear stress and glycated albumin on endothelial cell functions associated with inflammation,thrombosis and cytoskeletal dynamics

Aims/Introduction

Diabetes mellitus is a major risk factor in the development of cardiovascular diseases (CVDs). The presence of advanced glycation end‐products (AGEs) promotes CVDs by upregulating endothelial cell (EC) inflammatory and thrombotic responses, in a similar manner as disturbed shear stress. However, the combined effect of disturbed shear stress and AGEs on EC function has yet to be determined. Our goal was to evaluate these effects on EC responses.

Materials and Methods

ECs were incubated with AGEs for 5 days. ECs were then subjected to physiological or pathological shear stress. Cell metabolic activity, surface expression of intercellular adhesion molecule‐1, thrombomodulin, connexin‐43 and caveolin‐1, and cytoskeleton organization were quantified.

Results

The results show that irreversibly glycated albumin and pathological shear stress increased EC metabolic activity, and upregulated and downregulated the EC surface expression of intercellular adhesion molecule‐1 and thrombomodulin, respectively. Expression of connexin‐43, caveolin‐1 and cytoskeletal organization was independent of shear stress; however, the presence of irreversibly glycated AGEs markedly increased connexin‐43, and decreased caveolin‐1 expression and actin cytoskeletal connectivity.

Conclusions

Our data suggest that irreversibly glycated albumin and disturbed shear stress could promote CVD pathogenesis by enhancing EC inflammatory and thrombotic responses, and through the deterioration of the cytoskeletal organization.