Early inner retinal thinning and cardiovascular autonomic dysfunction in type 2 diabetes

Background

To investigate changes in the neural retina according to the presence of retinal nerve fiber layer (RNFL) defects in type 2 diabetes, and to determine the association between inner retina thickness and the severity of diabetic complications.

Methods

We studied non-glaucomatous patients with type 2 diabetes and control subjects Circumpapillary RNFL and macula ganglion cell-inner plexiform layer (GCIPL) thicknesses were measured by spectral-domain optical coherence tomography. In patients with type 2 diabetes, a cardiovascular autonomic function test (AFT) was performed, which included the heart rate parameter of beat-beat variation—with deep breathing, in response to the Valsalva maneuver, and on postural change from lying to standing. The results of each test were scored as 0 for normal and 1 for abnormal. A total AFT score of 1 was defined as early cardiovascular autonomic neuropathy (CAN), and an AFT score≥ 2 as definite CAN.

Results

We compared control eyes (n = 70), diabetic eyes with RNFL defects (n = 47), and eyes without RNFL defects (n = 30). The average RNFL and GCIPL thicknesses were significantly different among groups (all, P<0.05). On post-hoc testing, diabetic eyes with RNFL defects had a significantly thinner average GCIPL thickness than those without RNFL defects. On multivariate analyses, significantly thinner average GCIPL was seen in early CAN staging (B = -4.32, P = 0.016) and in definite CAN staging (B = -10.33, P<0.001), compared with no CAN involvement, after adjusting for confounding parameters.

Conclusions

Cardiovascular autonomic dysfunction was associated with early neurodegenerative changes in type 2 diabetes.

Improved trends in cardiovascular complications among subjects with type 2 diabetes in Korea: a nationwide study (2006-2013)

Background

Representative data on the secular trends in cardiovascular disease (CVD) are limited in Asian populations with diabetes. We aimed to estimate the temporal trends in cardiovascular complications using Korean nationwide whole population-based claims data in subjects with and without diabetes.

Methods

Type 2 diabetes was defined as a current medication history of anti-diabetic drugs and the presence of International Classification of Diseases (ICD)-10 codes (E11–E14) as diagnosis. We compared the 8-year rates of six cardiovascular complications [i.e., ischemic heart disease, acute myocardial infarction (AMI), ischemic stroke, hemorrhagic stroke, percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG)] in Korean adults aged 30 years and older using data from four consecutive nationwide databases (2006–2007, 2008–2009, 2010–2011, and 2012–2013) of Korean national health insurance service.

Results

A total of 1,645,348, 1,971,559, 2,291,247, and 2,562,612 subjects with type 2 diabetes were found in the year of 2006–2007, 2008–2009, 2010–2011, and 2012–2013, respectively. Age and gender standardized rates of the six predefined cardiovascular complications decreased in Korean adults with type 2 diabetes during the study period. The greatest relative reductions were observed for hospitalization due to AMI (−37.28%), followed by hospitalizations due to ischemic stroke (−36.98%). In the overall population without type 2 diabetes, the greatest relative reductions were observed for hospitalization for hemorrhagic stroke (−29.47%), followed by hospitalization due to ischemic stroke (−28.92%). Relative decreases in all six predefined cardiovascular complications were generally more profound in adults with diabetes than in those without diabetes, which led to significant decrease in the relative risks of all six cardiovascular complications in subjects with diabetes over the past 8 years. However, people with diabetes still had a two- to sixfold higher risk of hospitalization for major CVD events and interventions than people without diabetes.

Conclusions

Our findings suggest a significant reduction in the rate of people affected by CVD within the diabetic population. However, as the number of people with diabetes rises, the absolute burden of CVD will still be high in Korea.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-016-0482-6) contains supplementary material, which is available to authorized users.

Suppression of ROS Production by Exendin-4 in PSC Attenuates the High Glucose-Induced Islet Fibrosis

Pancreatic stellate cells (PSCs) play a major role to fibrotic islet destruction observed in diabetic patients and animal model of diabetes. Exendin-4 (Ex-4) is a potent insulinotropic agent and has been approved for the treatment of type 2 diabetes. However, there have been no reports demonstrating the effects of Ex-4 on pancreatic islet fibrosis. In this study, Ex-4 treatment clearly attenuated fibrotic islet destruction and improved glucose tolerance and islet survival. GLP-1 receptor expression was upregulated during activation and proliferation of PSCs by hyperglycemia. The activation of PKA pathway by Ex-4 plays a role in ROS production and angiotensin II (Ang II) production. Exposure to high glucose stimulated ERK activation and Ang II-TGF- β1 production in PSCs. Interestingly, Ex-4 significantly reduced Ang II and TGF-β1 production by inhibition of ROS production but not ERK phosphorylation. Ex-4 may be useful not only as an anti-diabetic agent but also as an anti-fibrotic agent in type 2 diabetes due to its ability to inhibit PSC activation and proliferation and improve islet fibrosis in OLETF rats.

Association between gamma-glutamyltransferase and albuminuria in nondiabetic adults with normal renal function

BACKGROUND

Serum gamma-glutamyltransferase (GGT) has been associated with albuminuria in diabetes patients, but it has not been investigated in the general population. We aimed to investigate the association between serum GGT and albuminuria in the nondiabetic Korean population with normal kidney function.

METHODS

Study participants (3948; 1549 men and 2399 women) with an estimated glomerular filtration rate ≥60 mL/min/1.73 m² were analyzed from the fifth Korean National Health and Nutrition Examination Survey (2011). Albuminuria was defined as an albumin-creatinine ratio >30 mg/g. Serum GGT was analyzed by dividing into quartiles. Multiple logistic models were used to analyze the associations between GGT and albuminuria.

RESULTS

The prevalence of albuminuria was 5.1% and increased linearly according to increasing GGT quartiles (P for trend = 0.005). A linear regression analysis revealed that GGT was positively related with albuminuria (P = 0.008). After adjusting for confounding factors, the odds ratio for albuminuria was 1.80 (95% CI 1.079-3.010, P for trend = 0.029) for the highest quartile group compared with those observed in the lowest quartile of GGT. In addition, this independent relationship did not change when the cut-off value of GGT (30 IU/L) was applied to this analysis. Compared with GGT value ≤30 IU/L, the adjusted odds ratio of albuminuria in participants with GGT >30 IU/L was 1.96 (95% CI 1.319-2.906, P < 0.001).

CONCLUSION

Higher serum GGT levels within the reference range were significantly associated with albuminuria in nondiabetic Koreans with preserved kidney function, independently of traditional cardio-renal risk factors.

Ion gyroscale fluctuation measurement with microwave imaging reflectometer on KSTAR

Ion gyroscale turbulent fluctuations with the poloidal wavenumber k_θ ∼ 3 cm^-1 have been measured in the core region of the neutral beam (NB) injected low confinement (L-mode) plasmas on Korea superconducting tokamak advanced research. The turbulence poloidal wavenumbers are deduced from the frequencies and poloidal rotation velocities in the laboratory frame, measured by the multichannel microwave imaging reflectometer. Linear and nonlinear gyrokinetic simulations also predict the unstable modes with the normalized wavenumber k_θρ_s ∼ 0.4, consistent with the measurement. Comparison of the measured frequencies with the intrinsic mode frequencies from the linear simulations indicates that the measured ones are primarily due to the E × B flow velocity in the NB-injected fast rotating plasmas.

Elevated lipoprotein(a) levels predict cardiovascular disease in type 2 diabetes mellitus: a 10-year prospective cohort study

BACKGROUND/AIMS

Elevated lipoprotein(a) (Lp[a]) level is known to be a risk factor for cardiovascular disease (CVD). However, the data that has been reported on the association between the Lp(a) level and CVD in type 2 diabetes has been limited and incoherent. The aim of this study was to investigate the relationship between the Lp(a) concentration and new onset CVD in type 2 diabetes.

METHODS

From March 2003 to December 2004, patients with type 2 diabetes without a prior history of CVD were consecutively enrolled. CVD was defined as the occurrence of coronary artery disease or ischemic stroke. Cox proportional hazards models were used to identify the associations between the Lp(a) and CVD after adjusting for confounding variables.

RESULTS

Of the 1,183 patients who were enrolled, 833 participants were evaluated with a median follow-up time of 11.1 years. A total of 202 participants were diagnosed with CVD (24.2%). The median Lp(a) level for 1st and 4th quartile group was 5.4 (3.5 to 7.1) and 55.7 mg/dL (43.1 to 75.3). Compared with patients without CVD, those with CVD were older, had a longer duration of diabetes and hypertension, and used more insulin and angiotensin converting enzyme inhibitors/angiotensin receptor blockers at baseline. A Cox hazard regression analysis revealed that the development of CVD was significantly associated with serum Lp(a) level (hazard ratio, 1.92; 95% confidence interval [CI], 1.26 to 2.92; p < 0.001, comparing the 4th vs. 1st quartile of Lp[a]).

CONCLUSIONS

Elevated Lp(a) level was an independent predictable risk factor for CVD in type 2 diabetes. Other cardiovascular risk factors should be treated more intensively in type 2 diabetic patients with high Lp(a) levels.

Effect of Sodium-Glucose Co-Transporter 2 Inhibitor, Dapagliflozin, on Renal Renin-Angiotensin System in an Animal Model of Type 2 Diabetes

Background

Renal renin-angiotensin system (RAS) activation is one of the important pathogenic mechanisms in the development of diabetic nephropathy in type 2 diabetes. The aim of this study was to investigate the effects of a sodium-glucose co-transporter 2 (SGLT-2) inhibitor, dapagliflozin, on renal RAS in an animal model with type 2 diabetes.

Methods

Dapagliflozin (1.0 mg/kg, OL-DA) or voglibose (0.6 mg/kg, OL-VO, diabetic control) (n = 10 each) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats for 12 weeks. We used voglibose, an alpha-glucosidase inhibitor, as a comparable counterpart to SGLT2 inhibitor because of its postprandial glucose-lowering effect without proven renoprotective effects. Control Long-Evans Tokushima Otsuka (LT) and OLETF (OL-C) rats received saline (n = 10, each). Changes in blood glucose, urine albumin, creatinine clearance, and oxidative stress were measured. Inflammatory cell infiltration, mesangial widening, and interstitial fibrosis in the kidney were evaluated by histological analysis. The effects of dapagliflozin on renal expression of the RAS components were evaluated by quantitative RT-PCR in renal tissue.

Results

After treatment, hyperglycemia and urine microalbumin levels were attenuated in both OL-DA and OL-VO rather than in the OL-C group (P < 0.05). The urine angiotensin II (Ang II) and angiotensinogen levels were significantly decreased following treatment with dapagliflozin or voglibose, but suppression of urine Ang II level was more prominent in the OL-DA than the OL-VO group (P < 0.05). The expressions of angiotensin type 1 receptor and tissue oxidative stress markers were markedly increased in OL-C rats, which were reversed by dapagliflozin or voglibose (P < 0.05, both). Inflammatory cell infiltration, mesangial widening, interstitial fibrosis, and total collagen content were significantly increased in OL-C rats, which were attenuated in OL-DA group (P < 0.05).

Conclusion

Dapagliflozin treatment showed beneficial effects on diabetic nephropathy, which might be via suppression of renal RAS component expression, oxidative stress and interstitial fibrosis in OLETF rats. We suggest that, in addition to control of hyperglycemia, partial suppression of renal RAS with an SGLT2 inhibitor would be a promising strategy for the prevention of treatment of diabetic nephropathy.

Diabetic Cardiovascular Autonomic Neuropathy Predicts Recurrent Cardiovascular Diseases in Patients with Type 2 Diabetes

Cardiovascular autonomic neuropathy (CAN) is a risk factor for cardiovascular disease (CVD) and mortality in patients with type 2 diabetes. This study evaluated the relationship between CAN and recurrent CVD in type 2 diabetes. A total of 206 patients with type 2 diabetes who had a history of CVD within 3 years of enrollment were consecutively recruited from January 2001 to December 2009 and followed-up until December 2015. Cardiovascular autonomic function tests were performed using the following heart rate variability parameters: expiration-to-inspiration ratio, response to Valsalva maneuver and standing. We estimated the recurrence of CVD events during the follow-up period. A total of 159 (77.2%) of the 206 patients enrolled completed the follow up, and 78 (49.1%) patients had recurrent episodes of CVD, with an incidence rate of 75.6 per 1,000 patient-years. The mean age and diabetes duration were 62.5 ± 8.7 and 9.2 ± 6.9 years, respectively. Patients who developed recurrent CVD also exhibited hypertension (P = 0.004), diabetic nephropathy (P = 0.012), higher mean systolic blood pressure (P = 0.006), urinary albumin excretion (P = 0.015), and mean triglyceride level (P = 0.035) than did patients without recurrent CVD. Multivariable Cox hazard regression analysis revealed that definite CAN was significantly associated with an increased risk of recurrent CVD (hazard ratio [HR] 3.03; 95% confidence interval [CI] 1.39−6.60; P = 0.005). Definite CAN was an independent predictor for recurrent CVD in patients with type 2 diabetes who had a known prior CVD event.

Probucol in Albuminuric Type 2 Diabetes Mellitus Patients on Renin–Angiotensin System Blockade

Objective—

To determine the effect of probucol on urine albumin excretion in type 2 diabetes mellitus patients with albuminuria using angiotensin-converting enzyme inhibitors or angiotensin receptor blockers.

Approach and Results—

This was a 16-week, phase II, randomized, placebo-controlled, parallel-group study in type 2 diabetes mellitus patients with a urinary albumin/creatinine ratio of ≥300 mg/g using angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, conducted in 17 tertiary referral hospitals. Eligible patients were randomized to probucol 250 mg/d (n=44), probucol 500 mg/d (n=41), and placebo (n=41) groups in a ratio of 1:1:1 after block randomization procedures, keeping the treatment assignment blinded to the investigators, patients, and study assistants. The primary end point was change in the geometric mean of urinary albumin/creatinine ratio from baseline to week 16 ( ClinicalTrials.gov identifier NCT01726816). The study was started on November 8, 2012, and completed on March 24, 2014. The least squares mean change±SE from baseline in urinary albumin/creatinine ratio at week 16 was −7.2±639.5 mg/g in the probucol 250 mg/d group (n=43; P =0.2077 versus placebo group), 9.3±587.4 mg/g in the probucol 500 mg/d group (n=40; P =0.1975 versus placebo group), and 259.0±969.1 mg/g in the placebo group (n=41). Although the majority of subjects were on statins, probucol treatment significantly lowered total cholesterol and low-density lipoprotein cholesterol levels. QT prolongation occurred in one and two subjects in control and probucol 250 mg/d groups, respectively.

Conclusions—

Four months of probucol up to 500 mg/d failed to reduce urinary albumin excretion.

Heavy Alcohol Consumption with Alcoholic Liver Disease Accelerates Sarcopenia in Elderly Korean Males: The Korean National Health and Nutrition Examination Survey 2008-2010

Background and Aim

Although a few studies have reported that sarcopenia is associated with alcoholic liver disease (ALD), no studies have investigated this association in a large sample representative of the elderly Korean population.

Methods

This was a cross-sectional study that used data from the Fourth and Fifth Korean National Health and Nutrition Examination Surveys (KNHANES) on subjects aged 65 years and older. Sarcopenia was defined as a skeletal muscle index (SMI) more than 1 SD below the gender-specific mean for young adults; SMI was calculated as the appendicular muscle mass divided by height squared (ASM/Ht²). Heavy alcohol consumption was defined as consuming at least 210 g/week, and elevated liver enzymes were defined as alanine aminotransferase levels of at least 32 U/L or aspartate aminotransferase levels of at least 34 U/L. ALD was defined as heavy alcohol consumption and elevated liver enzymes.

Results

The mean age of the 1,151 elderly males was 71.6 ± 0.2 years, and the prevalence of heavy alcohol consumption was 11.8% (136 subjects). SMI did not differ between the non-heavy and heavy alcohol consumer groups (7.1 ± 0.0 kg/m² vs. 7.3 ± 0.1 kg/m², respectively, P = 0.145). However, after stratifying by the presence of liver disease and heavy alcohol consumption and adjusting for other confounders in the multivariate logistic regression, SMI was significantly lower among heavy alcohol consumers with ALD (all P < 0.05). Additionally, two-way ANOVA showed a significant interaction between heavy alcohol consumption and liver disease (P = 0.011).

Conclusion

Sarcopenia was accelerated in the elderly male ALD group, with a significant interaction between alcohol consumption and liver disease.

Triglyceride glucose index, a marker of insulin resistance, is associated with coronary artery stenosis in asymptomatic subjects with type 2 diabetes

Background

Insulin resistance is one of the most important contributing factors to cardiovascular disease. This study aimed to investigate the association between coronary artery stenosis (CAS) and triglyceride glucose index (TyG index), a simple insulin resistance marker, in asymptomatic subjects with type 2 diabetes.

Methods

We recruited asymptomatic adults with type 2 diabetes but without previous history of coronary heart disease (n = 888). Significant CAS was defined as maximum intraluminal stenosis ≥70 % by coronary CT angiography. TyG index was calculated as log [fasting triglycerides (mg/dl) x fasting glucose (mg/dl)/2].

Results

Mean age was 63.8 ± 9.5 and 58.9 % of the subjects were men. We analyzed the participants according to the tertile of TyG index. The TyG index was correlated with HOMA-IR (r = 0.397, P < 0.001), and subjects with higher tertile of TyG index were younger but showed worse clinical and metabolic parameters. The prevalence of CAS was higher in subjects with higher tertile of TyG compared with those with lower tertile of TyG (14 % vs. 7.8 %, P = 0.022). On multiple regression analysis, the highest tertile of TyG index was an independent risk factor for CAS after adjustment for other confounders (odds ratio, 3.19 [95 % CI, 1.371–7.424]). Subgroup analysis showed that TyG index showed more significant association with CAS in patients with risk factors such as old age, longer duration of diabetes, poor glycemic control, no statin use, and male gender.

Conclusion

Higher TyG index is associated with increased risk of CAS in asymptomatic subjects with type 2 diabetes, particularly when they have risk factors for cardiovascular disease.

Trial registration

This study was retrospectively registered in ClinicalTrials. gov with the registration number of NCT02070926 in Feb 23, 2014.

Trends of antidiabetic drug use in adult type 2 diabetes in Korea in 2002-2013: Nationwide population-based cohort study

This study investigated trends in the prescription of antidiabetic medications for patients with type 2 diabetes, focusing on changing patterns of prescriptions and the cost of drugs during the last 10 years. Retrospective data on patients with type 2 diabetes aged 30 years or older were analyzed using information from the National Health Information Database collected by the National Health Insurance Service in Korea from January 2002 to December 2013. We identified patients with type 2 diabetes who had at least one service claim in each year during the study period. The prescribing information was collected and fixed-dose combination tablets were counted as each of their constituent classes. The total number of adults with type 2 diabetes who were treated using antidiabetic agents increased from 0.87 million in 2002 to 2.72 million in 2013 in Korea. Among antidiabetic medications in 2002, sulfonylurea (SU) was the most commonly used agent (87.2%), and metformin was the second (52.9%). However, in 2013, the use of metformin increased to 80.4% of the total antidiabetic prescriptions. The use of dipeptidyl peptidase-4 (DPP-4) inhibitor increased remarkably after release in late 2008 and composed one-third of the market share with 1 million prescriptions (38.4%) in 2013. Among the prescriptions for monotherapy, only 13.0% were metformin in 2002, but the amount increased to 53.2% by 2013. In contrast, the use of SU declined dramatically from 75.2% in 2002 to 30.6% in 2013. Dual and triple combinations steadily increased from 35.0% and 6.6% in 2002 to 44.9% and 15.5% in 2013, respectively. In 2013, SU with metformin (41.7%) and metformin with DPP-4 inhibitor (32.5%) combination were most frequently prescribed. The total antidiabetic medication cost increased explosively from U.S. $70 million (82.5 billion won) in 2002 to U.S. $4 billion (480 billion won) in 2013.The use of antidiabetic agents and their costs have been increasing steadily. Metformin is the most commonly used drug recently. The use of DPP-4 inhibitor increased significantly over the past decade, whereas the use of SU decreased. However, SUs still remain the most commonly prescribed second-line agents with metformin in 2013.

Cardiovascular Autonomic Dysfunction Predicts Diabetic Foot Ulcers in Patients With Type 2 Diabetes Without Diabetic Polyneuropathy

We investigated the factors that might influence the development of diabetic foot ulcers (DFUs) in type 2 diabetes patients without diabetic polyneuropathy (DPN).From January 2000 to December 2005, a total of 595 patients who had type 2 diabetes without DPN between the ages of 25 and 75 years, and had no prior history of DFUs were consecutively enrolled in the study. A cardiovascular autonomic function test was performed to diagnose cardiovascular autonomic neuropathy (CAN) using heart rate variability parameters.The median follow-up time was 13.3 years. Among the 449 (75.4%) patients who completed the follow-up evaluation, 22 (4.9%) patients developed new ulcers, and 6 (1.3%) patients underwent the procedure for lower extremity amputations. The patients in the DFUs group had a longer duration of diabetes, higher baseline HbA1c levels, higher rates of nephropathy, and CAN. A Cox hazard regression analysis results revealed that the development of DFUs was significantly associated with the presence of CAN (normal vs definite CAN; HR, 4.45; 95% confidence interval, 1.29-15.33) after adjusting for possible confounding factors.The development of DFUs was independently associated with CAN in patients with type 2 diabetes without DPN. We suggested the importance of CAN as a predictor of DFUs even in the patients without DPN, and the need to pay attention to patients with definite CAN and type 2 diabetes.

Lipoprotein(a) predicts the development of diabetic retinopathy in people with type 2 diabetes mellitus

BACKGROUND

Lipoprotein(a) [Lp(a)] has mainly been considered to be a predictor of the incidence of cardiovascular disease. In addition, previous studies have shown potential linkage between Lp(a) and diabetic microvascular complications.

OBJECTIVES

We investigated the incidence and risk factors for the development of diabetic retinopathy (DR) in patients with type 2 diabetes.

METHODS

A total of 787 patients with type 2 diabetes without DR were consecutively enrolled and followed up prospectively. Retinopathy evaluation was annually performed by ophthalmologists. The main outcome was new onset of DR.

RESULTS

The median follow-up time was 11.1 years. Patients in the DR group had a longer duration of diabetes (P < .001), higher baseline HbA1c (P < .001), higher albuminuria level (P = .033), and higher level of Lp(a) (P = .005). After adjusting for sex, age, diabetes duration, presence of hypertension, renal function, LDL cholesterol, mean HbA1c, and medications, the development of DR was significantly associated with the serum Lp(a) level (HR 1.57, 95% confidence interval [1.11-2.24]; P = .012, comparing the 4th vs 1st quartile of Lp(a)). The patient group with the highest quartile range of Lp(a) and mean HbA1c levels ≥7.0% had an HR of 5.09 (95% confidence interval [2.63-9.84]; P < .001) for developing DR compared with patients with lower levels of both factors.

CONCLUSIONS

In this prospective cohort study, we demonstrated that the DR was independently associated with the serum Lp(a) level in patients with type 2 diabetes.

Low muscle mass is associated with metabolic syndrome only in nonobese young adults: the Korea National Health and Nutrition Examination Survey 2008-2010

Little is known about the relationship between body composition and metabolic risk factors in young adults. We hypothesized that low muscle mass (LMM) is associated with metabolic syndrome (MetS) and its components in young adults and that the associations vary by obesity. A cross-sectional analysis was conducted using the Korea National Health and Nutrition Examination Survey data. In total, 5300 young adults aged 19 to 39 years were evaluated. Low muscle mass was defined as an appendicular skeletal muscle mass/weight less than 1 SD below the mean for each participant's corresponding sex and age group. Obesity was defined as a body mass index greater than or equal to 25 kg/m2. The prevalence of LMM was higher in obese than nonobese participants (37.6% vs. 9.6%). In the nonobese participants, the prevalence of MetS, high waist circumference, high triglycerides, and high blood pressure was significantly greater in the LMM group than in the high muscle mass group. In the nonobese group, compared with high muscle mass participants, those with LMM had odds ratios for MetS of 3.6 (95% confidence interval, 1.48-8.76; P < .001) and 3.6 (95% confidence interval, 1.48-8.71; P < .001) in men and women, respectively, after adjusting for confounding factors. However, no significant association of LMM with MetS or its components was found in obese participants. In conclusion, our results suggest that young adults with LMM may have a high risk of MetS, especially when they are nonobese. Interventions aimed at increasing muscle mass at younger ages may have the potential to reduce MetS.

Increased liver markers are associated with higher risk of type 2 diabetes

AIM: To investigate the association between liver markers and the risk of type 2 diabetes (T2DM) and impaired fasting glucose (IFG).

METHODS: A total of 8863 participants (3408 men and 5455 women) over 30 years of age were analyzed from the fifth Korean National Health and Nutrition Examination Survey (2010-2011). The associations of serum liver markers such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), AST/ALT, and gamma-glutamyltransferase (GGT) with T2DM and IFG were analyzed using logistic regression models. Participants were divided into sex-specific quartiles on the basis of liver markers.

RESULTS: The prevalence of T2DM and IFG were 11.3% and 18.3%. Increasing quartiles of ALT and GGT were positively and AST/ALT were negatively correlated with T2DM and IFG. Analysis of the liver marker combinations showed that if any two or more markers were in the highest risk quartile, the risks of both T2DM and IFG increased significantly. The risk was greatest when the highest ALT and GGT and lowest AST/ALT quartile were combined, with the risk of T2DM at 3.21 (95%CI: 1.829-5.622, P < 0.001) in men and 4.60 (95%CI: 3.217-6.582, P < 0.001) in women. Men and women with the highest AST and ALT and lowest AST/ALT quartile had a 1.99 and 2.40 times increased risk of IFG.

CONCLUSION: Higher levels of GGT and ALT and lower AST/ALT within the physiological range are independent, additive risk factors of T2DM and IFG.

The flavone eupatilin inhibits eotaxin expression in an NF-κB-dependent and STAT6-independent manner

The CC chemokine eotaxin contributes to epithelium-induced inflammation in airway diseases such as asthma. Eupatilin (5,7-dihydroxy-3',4',6'-trimethoxyflavone), a bioactive component of Artemisia asiatica Nakai (Asteraceae), is reported to inhibit the adhesion of eosinophils to bronchial epithelial cells. However, little is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelium-induced inflammation. In this study, we investigated the effect of eupatilin on expression of eotaxin-1 (CCL11), a potent chemoattractant for eosinophils. Eupatilin significantly inhibited eotaxin expression in bronchial epithelial cells stimulated with TNF-α, while NF-κB and IκBα kinase (IKK) activities declined concurrently. Eupatilin also inhibited mitogen-activated protein kinase (MAPK) activity; however, all of these anti-inflammatory activities were reversed by MAPK overexpression. In contrast, eupatilin did not affect the signal transducer and activator of transcription 6 (STAT6) signalling in bronchial epithelial cells stimulated with IL-4. Furthermore, eupatilin significantly attenuated TNF-α-induced eosinophil migration. These results suggest that the eupatilin inhibits the signalling of MAPK, IKK, NF-κB and eotaxin-1 in bronchial epithelial cells, leading to inhibition of eosinophil migration.

Intensive individualized reinforcement education is important for the prevention of hypoglycemia in patients with type 2 diabetes

BACKGROUND

We investigated whether an intensive individualized reinforcement education program could influence the prevention of hypoglycemic events in patients with type 2 diabetes.

METHODS

From March 2013 to September 2013, patients aged 35 to 75 years with type 2 diabetes who had not previously participated in diabetes education, and treated with insulin or a sulfonylurea-containing regimen were included in the study. After structured group education, the patients assigned to the intensive individualized education group (IT) were requested to visit for reinforcement. All subjects in the IT were encouraged to self-manage dose adjustments. Participants in both groups (control group [CG, group education only; n=22] and IT [n=24]) attended follow-up visits at 2, 8, 12, and 24 weeks. At each visit, all patients were asked whether they had experienced hypoglycemia.

RESULTS

The total study population consisted of 20 men (43.5%; mean age and diabetic duration of 55.9±11.0 and 5.1±7.3 years, respectively). At 24 weeks, there were no significant differences in hemoglobin A1c values between the CG and IT. The total number of hypoglycemic events per patient was 5.26±6.5 in the CG and 2.58±2.3 times in the IT (P=0.004). Adherence to lifestyle modification including frequency of exercise, self-monitoring of blood glucose, or dietary habit was not significantly different between the groups. However, adherence to hypoglycemia management, especially the dose adjustment of medication, was significantly higher in the IT compared with the CG.

CONCLUSION

Compared with the structured group education, additional IT resulted in additional benefits in terms of avoidance of hypoglycemia and treating hypoglycemia in patients with type 2 diabetes.

The association between abnormal heart rate variability and new onset of chronic kidney disease in patients with type 2 diabetes: a ten-year follow-up study

AIMS

We investigated the association between cardiovascular autonomic neuropathy (CAN) and the future development of chronic kidney disease (CKD) in patients with type 2 diabetes.

METHODS

From Jan 2003 to Dec 2004, 1117 patients with type 2 diabetes without CKD (estimated glomerular filtration rate [eGFR] ≥ 60 ml/min/1.73 m(2)), aged 25-75 years, were consecutively enrolled. A cardiovascular autonomic function test (AFT) was performed using heart rate variability parameters. The eGFR was measured at least more than once every year, and new onset CKD was defined as eGFR < 60 ml/min/1.73 m(2) using a Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Among the 755 (67.6%) patients who completed the follow-up evaluation for 9.6 years, 272 patients (36.0%) showed a CKD stage ≥3. The patients who developed CKD were older, had a longer duration of diabetes, had hypertension, received more insulin and ACE inhibitor/angiotensin receptor blocker (ARB) treatment, and exhibited lower baseline eGFR, HbA1c, and albuminuria levels. Compared to patients without CKD, more patients with CKD at follow-up had CAN at baseline. In a multivariate analysis, after adjustment for age, sex, diabetes duration, presence of hypertension, mean HbA1c, diabetic complications, use of insulin, ACE inhibitor/ARB, statin, and baseline eGFR, the development of CKD was significantly associated with the presence of CAN (HR 2.62, 95% CI 1.87-3.67, P<0.001).

CONCLUSIONS

In this prospective, longitudinal, observational cohort study, we demonstrated that diabetic CAN was an independent prognostic factor for the future development of CKD in type 2 diabetes.

Retinal nerve fiber layer loss is associated with urinary albumin excretion in patients with type 2 diabetes

OBJECTIVES

To identify the factors associated with retinal nerve fiber layer (RNFL) loss in patients with type 2 diabetes.

DESIGN

Cross-sectional study.

PARTICIPANTS

Ninety-six nonglaucomatous patients with type 2 diabetes without renal impairment (estimated glomerular filtration rate, ≥60 ml/minute per 1.73 m(2)).

METHODS

Eyes were divided into 2 groups based on the presence or absence of RNFL defects detected by red-free retinal fundus photography. All participants underwent an eye fundus examination, and the urinary albumin-to-creatinine ratio (ACR) was determined. A cardiovascular autonomic function test was performed using the following heart rate variability parameters: expiration-to-inspiration ratio, response to the Valsalva maneuver, and standing. Multiple logistic regression analyses were performed to determine potential risk factors related to the presence of RNFL defects in these patients.

MAIN OUTCOMES AND MEASURES

The association between RNFL defects and diabetic complications.

RESULTS

Among the patients, 43 (44.8%) had localized RNFL defects (group 1), whereas the others (55.2%) did not (group 2). The RNFL defects occurred more frequently on the superior side (75.6% and 71.0% in right and left eyes, respectively) compared with the inferior side (13.8% and 0.0% in right and left eyes, respectively). Patients with RNFL defects (group 1) had significantly higher rates of diabetic retinopathy (60.5%) compared with those without RNFL defects (group 2; 32.1%; P = 0.007). The urinary ACR was significantly higher in patients with RNFL defects than in those without defects (45.3±72.1 μg/mg vs. 15.4±17.3 μg/mg creatinine, respectively; P = 0.015), whereas autonomic function test grading was similar between the groups. The urinary ACR was the only factor related to visual field defect location in both univariate (P = 0.021) and multivariate (P = 0.036) logistic regression analyses after adjusting for age; gender; presence of diabetic retinopathy; diabetes duration; smoking; statin use; and antiplatelet, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker treatment.

CONCLUSIONS

Urinary albumin excretion was associated with nerve fiber layer loss in patients with type 2 diabetes. Careful examination of the optic nerve head may be necessary, particularly in patients with type 2 diabetes exhibiting albuminuria.

Avoiding or coping with severe hypoglycemia in patients with type 2 diabetes

Hypoglycemia is a major barrier to achieving the glycemic goal in patients with type 2 diabetes. In particular, severe hypoglycemia, which is defined as an event that requires the assistance of another person to actively administer carbohydrates, glucagon, or take other corrective actions, is a serious clinical concern in patients with diabetes. If severe hypoglycemia is not managed promptly, it can be life threatening. Hypoglycemia-associated autonomic failure (HAAF) is the main pathogenic mechanism behind severe hypoglycemia. Defective glucose counter-regulation (altered insulin secretion, glucagon secretion, and an attenuated increase in epinephrine during hypoglycemia) and a lack of awareness regarding hypoglycemia (attenuated sympathoadrenal activity) are common components of HAAF in patients with diabetes. There is considerable evidence that hypoglycemia is an independent risk factor for cardiovascular disease. In addition, hypoglycemia has a significant influence on the quality of life of patients with diabetes. To prevent hypoglycemic events, the setting of glycemic goals should be individualized, particularly in elderly individuals or patients with complicated or advanced type 2 diabetes. Patients at high-risk for the future development of severe hypoglycemia should be selected carefully, and intensive education with reinforcement should be implemented.

The control of blood pressure might be important in delaying progression of arterial aging in patients with type 2 diabetes mellitus

Objective

Arterial stiffness, as assessed by the brachial-ankle pulse wave velocity (baPWV), is associated with arterial aging and has been consistently linked to cardiovascular disease. The factors involved in reducing the progression of arterial stiffness in patients with type 2 diabetes mellitus (DM) have not yet been fully established.

Methods

Of 478 patients who underwent two baPWV measurements (at baseline and 1 year later) at the Department of Internal Medicine, St Vincent’s Hospital, from November 2009 to June 2011, 341 subjects were enrolled in this study (male to female ratio =150:191; mean age, 62.1±7.7 years). The 341 subjects were over the age of 50 with type 2 DM, were diagnosed without peripheral artery disease, and 170 if the subjects (50%) had hypertension.

Results

baPWV at baseline increased in a linear manner along with age (β=22.8, t=10.855; P<0.0001, R²=0.258). After 1 year follow-up, the change in baPWV (ΔbaPWV) was variable (median 32.7 cm/s [approximate range, −557 to ∼745]). In multiple linear regression, the change in systolic blood pressure (β=7.142, 95% confidence interval =4.557–9.727; P<0.0001, R²=0.305) was associated with ΔbaPWV during follow-up. The change in glycated hemoglobin (HbA_1c) and a glycemic control of keeping HbA_1c levels below 7.0% were not associated with ΔbaPWV.

Conclusion

We found that the variation of blood pressure was associated with the progression of vascular aging of the large- to middle-sized arteries in patients with type 2 DM. Therefore, control of blood pressure might be important in reducing arterial aging or PWV in patients with type 2 DM.