Distribution of Urinary Trace Element Exposure and Dietary Sources in Women Over 50 in an Agricultural Region- A community-based KoGES cohort study

BACKGROUND

There is a noticeable lack of information on the levels of both non-essential and essential trace elements in women aged over 50. The main objective of this study is to investigate trace element concentrations and explore the influence of sociodemographic factors and dietary sources of exposure in this demographic.

METHODS

We analyzed 19 trace elements, including manganese, cobalt, copper, zinc, molybdenum, chromium, nickel, arsenic, strontium, cadmium, tin, antimony, cesium, barium, tungsten, mercury, thallium, lead, and uranium, using ICP-MS. Urine samples were obtained from a cohort of 851 women aged over 50 who participated in the 8th KoGES-Ansung study (2015-2016). Multiple linear models were employed to explore associations between urinary trace element concentrations and sociodemographic factors and dietary sources of exposure. We used K-means clustering to discern patterns of exposure to trace elements and identify contributing factors and sources within our study population.

RESULTS

Our findings indicate higher concentrations of molybdenum (Mo), arsenic (As), cadmium (Cd), and lead (Pb) in our study population compared to women in previous studies. The study population were clustered into two distinct groups, characterized by lower or higher urinary concentrations. Significant correlations between age and urinary concentrations were observed in Mo and Ni. Smoking exhibited positive associations with urinary Cd and As. Associations with dietary sources of trace elements were more distinct in women in the high-exposure group. Urinary antimony (Sb) was positively linked to mushroom and egg intake, As to mushroom and fish, and Hg to egg, dairy products, fish, seaweed, and shellfish.

CONCLUSIONS

Our study underscores the significant gap in understanding urinary concentrations of trace elements in women aged over 50. With higher concentrations of certain elements compared to previous studies and significant correlations between age, smoking, and specific food sources, it is imperative to address this gap through targeted dietary source-specific risk management.

A Multicenter, Randomized, Open-Label Study to Compare the Effects of Gemigliptin Add-on or Escalation of Metformin Dose on Glycemic Control and Safety in Patients with Inadequately Controlled Type 2 Diabetes Mellitus Treated with Metformin and SGLT-2 Inhibitors (SO GOOD Study)

Background

We aimed to compare efficacy and safety between gemigliptin add-on and escalation of the metformin dose in patients with inadequately controlled type 2 diabetes mellitus (T2DM) despite treatment with metformin and SGLT2 inhibitors.

Methods

This study was a multicenter, randomized, open-label, active-controlled, parallel-group comparative study. Patients with T2DM uncontrolled on metformin and SGLT2 inhibitors were randomized to receive gemigliptin 50 mg as an add-on (GEM group, n = 37) or escalation of the metformin dose (500 mg, MET group, n = 38) for 24 weeks. The primary endpoint was the change in glycosylated hemoglobin (HbA1c) from baseline to week 24.

Results

At weeks 12 and 24, the reduction in HbA1c levels was significantly greater in the GEM group than in the MET group (GEM vs. MET = -0.64% ± 0.34% vs. -0.36% ± 0.50%, p = 0.009 at week 12; -0.61% ± 0.35% vs. -0.33% ± 0.70%, p = 0.045 at week 24). The proportions of patients who achieved target HbA1c levels of <7.0% at weeks 12 and 24 and <6.5% at week 12 were greater in the GEM group than in the MET group. An index of β-cell function was also significantly improved in the GEM group. The safety profiles were similar between the two groups.

Conclusions

Gemigliptin add-on therapy may be more effective than metformin dose escalation in patients with T2DM insufficiently controlled using metformin and SGLT2 inhibitors, without safety concerns. This trial is registered with CRIS_number: KCT0003520.

The clinical course of hospitalized COVID-19 patients and aggravation risk prediction models: a retrospective, multi-center Korean cohort study

Background

Understanding the clinical course and pivotal time points of COVID-19 aggravation is critical for enhancing patient monitoring. This retrospective, multi-center cohort study aims to identify these significant time points and associate them with potential risk factors, leveraging data from a sizable cohort with mild-to-moderate symptoms upon admission.

Methods

This study included data from 1,696 COVID-19 patients with mild-to-moderate clinical severity upon admission across multiple hospitals in Daegu-Kyungpook Province (Daegu dataset) between February 18 and early March 2020 and 321 COVID-19 patients at Seoul Boramae Hospital (Boramae dataset) collected from February to July 2020. The approach involved: (1) identifying the optimal time point for aggravation using survival analyses with maximally selected rank statistics; (2) investigating the relationship between comorbidities and time to aggravation; and (3) developing prediction models through machine learning techniques. The models were validated internally among patients from the Daegu dataset and externally among patients from the Boramae dataset.

Results

The Daegu dataset showed a mean age of 51.0 ± 19.6 years, with 8 days for aggravation and day 5 being identified as the pivotal point for survival. Contrary to previous findings, specific comorbidities had no notable impact on aggravation patterns. Prediction models utilizing factors including age and chest X-ray infiltration demonstrated promising performance, with the top model achieving an AUC of 0.827 in external validation for 5 days aggravation prediction.

Conclusion

Our study highlights the crucial significance of the initial 5 days period post-admission in managing COVID-19 patients. The identification of this pivotal time frame, combined with our robust predictive models, provides valuable insights for early intervention strategies. This research underscores the potential of proactive monitoring and timely interventions in enhancing patient outcomes, particularly for those at risk of rapid aggravation. Our findings offer a meaningful contribution to understanding the COVID-19 clinical course and supporting healthcare providers in optimizing patient care and resource allocation.

2023 Clinical Practice Guidelines for Diabetes Mellitus of the Korean Diabetes Association

In May 2023, the Committee of Clinical Practice Guidelines of the Korean Diabetes Association published the revised clinical practice guidelines for Korean adults with diabetes and prediabetes. We incorporated the latest clinical research findings through a comprehensive systematic literature review and applied them in a manner suitable for the Korean population. These guidelines are designed for all healthcare providers nationwide, including physicians, diabetes experts, and certified diabetes educators who manage patients with diabetes or individuals at risk of developing diabetes. Based on recent changes in international guidelines and the results of a Korean epidemiological study, the recommended age for diabetes screening has been lowered. In collaboration with the relevant Korean medical societies, recently revised guidelines for managing hypertension and dyslipidemia in patients with diabetes have been incorporated into this guideline. An abridgment containing practical information on patient education and systematic management in the clinic was published separately.

Gene-diet interaction analysis using novel weighted food scores discovers the adipocytokine signaling pathway associated with the development of type 2 diabetes

Introduction

The influence of dietary patterns measured using Recommended Food Score (RFS) with foods with high amounts of antioxidant nutrients for Type 2 diabetes (T2D) was analyzed. Our analysis aims to find associations between dietary patterns and T2D and conduct a gene-diet interaction analysis related to T2D.

Methods

Data analyzed in the current study were obtained from the Korean Genome and Epidemiology Study Cohort. The dietary patterns of 46 food items were assessed using a validated food frequency questionnaire. To maximize the predictive power of the RFS, we propose two weighted food scores, namely HisCoM-RFS calculated using the novel Hierarchical Structural Component model (HisCoM) and PLSDA-RFS calculated using Partial Least Squares-Discriminant Analysis (PLS-DA) method.

Results

Both RFS (OR: 1.11; 95% CI: 1.03- 1.20; P = 0.009) and PLSDA-RFS (OR: 1.10; 95% CI: 1.02-1.19, P = 0.011) were positively associated with T2D. Mapping of SNPs (P < 0.05) from the interaction analysis between SNPs and the food scores to genes and pathways yielded some 12 genes (CACNA2D3, RELN, DOCK2, SLIT3, CTNNA2, etc.) and pathways associated with T2D. The strongest association was observed with the adipocytokine signalling pathway, highlighting 32 genes (STAT3, MAPK10, MAPK8, IRS1, AKT1-3, ADIPOR2, etc.) most likely associated with T2D. Finally, the group of the subjects in low, intermediate and high using both the food scores and a polygenic risk score found an association between diet quality groups with issues at high genetic risk of T2D.

Conclusion

A dietary pattern of poor amounts of antioxidant nutrients is associated with the risk of T2D, and diet affects pathway mechanisms involved in developing T2D.

Earlier Age at Type 2 Diabetes Diagnosis Is Associated With Increased Genetic Risk of Cardiovascular Disease

OBJECTIVE

We investigated genetic risk of cardiovascular disease (CVD) by age at type 2 diabetes (T2D) diagnosis.

RESEARCH DESIGN AND METHODS

We compared incident CVD events by age at T2D diagnosis using UK Biobank (N = 12,321) and the Seoul National University Hospital (SNUH) cohort (N = 1,165). Genetic risk was quantified using polygenic risk score (PRS).

RESULTS

Individuals with earlier T2D diagnosis had higher CVD risk. In UK Biobank, the effect size of coronary artery disease (CAD) PRS on incident CAD was largest in individuals diagnosed with T2D at ages 30-39 years (hazard ratio 2.25; 95% CI 1.56-3.26) and decreased as age at diagnosis increased: ages 40-49 (1.51; 1.30-1.75), 50-59 (1.36; 1.24-1.50), and 60-69 years (1.30; 1.14-1.48) (Pinteraction = 0.0031). A similar trend was observed in the SNUH cohort. This increased genetic risk associated with earlier T2D diagnosis was largely mitigated by a healthy lifestyle.

CONCLUSIONS

Individuals with an earlier T2D diagnosis have a higher genetic risk of CAD, and this information could be used to tailor lifestyle interventions.

Comparison of Operational Definition of Type 2 Diabetes Mellitus Based on Data from Korean National Health Insurance Service and Korea National Health and Nutrition Examination Survey

BACKGROUND

We evaluated the validity and reliability of the operational definition of type 2 diabetes mellitus (T2DM) based on the Korean National Health Insurance Service (NHIS) database.

METHODS

Adult subjects (≥40 years old) included in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2017 were merged with those from the NHIS health check-up database, producing a cross-sectional dataset. We evaluated the sensitivity, specificity, accuracy, and agreement of the NHIS criteria for defining T2DM by comparing them with the KNHANES criteria as a standard reference.

RESULTS

In the study population (n=13,006), two algorithms were devised to determine from the NHIS dataset whether the diagnostic claim codes for T2DM were accompanied by prescription codes for anti-diabetic drugs (algorithm 1) or not (algorithm 2). Using these algorithms, the prevalence of T2DM was 14.9% (n=1,942; algorithm 1) and 20.8% (n=2,707; algorithm 2). Good reliability in defining T2DM was observed for both algorithms (Kappa index, 0.73 [algorithm 1], 0.63 [algorithm 2]). However, the accuracy (0.93 vs. 0.89) and specificity (0.96 vs. 0.90) tended to be higher for algorithm 1 than for algorithm 2. The validity (accuracy, ranging from 0.91 to 0.95) and reliability (Kappa index, ranging from 0.68 to 0.78) of defining T2DM by NHIS criteria were independent of age, sex, socioeconomic status, and accompanied hypertension or dyslipidemia.

CONCLUSION

The operational definition of T2DM based on population-based NHIS claims data, including diagnostic codes and prescription codes, could be a valid tool to identify individuals with T2DM in the Korean population.

Cardiovascular Outcomes according to Comorbidities and Low-Density Lipoprotein Cholesterol in Korean People with Type 2 Diabetes Mellitus

BACKGROUND

There are no clear data to support the cardiovascular (CV) risk categories and low-density lipoprotein cholesterol (LDL-C) treatment goals in Korean people with type 2 diabetes mellitus (T2DM). We evaluated the incidence of cardiovascular disease (CVD) according to comorbidities and suggested LDL-C treatment goals in Korean people with T2DM in nationwide cohort data.

METHODS

Using the Korean National Health Insurance Service database, 248,002 people aged 30 to 90 years with T2DM who underwent routine health check-ups during 2009 were included. Subjects with previous CVD were excluded from the study. The primary outcome was incident CVD, defined as a composite of myocardial infarction and ischemic stroke during the follow-up period from 2009 to 2018.

RESULTS

The mean age of the study participants was 59.6±10.9 years, and median follow-up period was 9.3 years. CVD incidence increased in the order of DM duration of 5 years or more (12.04/1,000 person-years), hypertension (HT) (12.27/1,000 personyears), three or more CV risk factors (14.10/1,000 person-years), and chronic kidney disease (18.28/1,000 person-years). The risk of incident CVD increased linearly from an LDL-C level of ≥70 mg/dL in most patients with T2DM. In T2DM patients without HT or with a DM duration of less than 5 years, the CVD incidence increased from LDL-C level of ≥100 mg/dL.

CONCLUSION

For primary prevention of CVD in Korean adults with T2DM, it can be helpful to lower LDL-C targets when there are chronic kidney disease, HT, a long duration of diabetes mellitus, or three or more CV risk factors.

Lipid Management in Korean People with Type 2 Diabetes Mellitus: Korean Diabetes Association and Korean Society of Lipid and Atherosclerosis Consensus Statement

Dyslipidemia in patients with diabetes is an important treatment target as a modifiable risk factor for cardiovascular disease (CVD). Although the primary treatment goal for dyslipidemia is to control low-density lipoprotein cholesterol (LDL-C), achieving this goal remains suboptimal according to recent studies. It is important to set the target goal for LDL-C control based on an accurate risk assessment for CVD. Here, we summarize the latest evidence on lipid management in patients with diabetes and present a consensus of the Korean Diabetes Association and Korean Society of Lipid and Atherosclerosis on the treatment goals of LDL-C according to the duration of diabetes, presence of CVD, target organ damage, or major cardiovascular risk factors. In patients with type 2 diabetes mellitus (T2DM) and CVD, an LDL-C goal of <55 mg/dL and a reduction in LDL-C level by 50% or more from the baseline is recommended. For the primary prevention of CVD in patients with T2DM with a duration of diabetes ≥10 years, major cardiovascular risk factors, or target organ damage, an LDL-C goal of <70 mg/dL is recommended. In patients with T2DM with a duration of diabetes <10 years and no major cardiovascular risk factors, an LDL-C goal of <100 mg/dL is recommended.

Evaluation and Management of Patients With Diabetes and Heart Failure: A Korean Diabetes Association and Korean Society of Heart Failure Consensus Statement

Diabetes mellitus is a major risk factor for the development of heart failure. Furthermore, the prognosis of heart failure is worse in patients with diabetes mellitus than in those without it. Therefore, early diagnosis and proper management of heart failure in patients with diabetes mellitus are important. This review discusses the current criteria for diagnosis and screening tools for heart failure and the currently recommended pharmacological therapies for heart failure. We also highlight the effects of anti-diabetic medications on heart failure.

Evaluation and Management of Patients with Diabetes and Heart Failure: A Korean Diabetes Association and Korean Society of Heart Failure Consensus Statement

Diabetes mellitus is a major risk factor for the development of heart failure. Furthermore, the prognosis of heart failure is worse in patients with diabetes mellitus than in those without it. Therefore, early diagnosis and proper management of heart failure in patients with diabetes mellitus are important. This review discusses the current criteria for diagnosis and screening tools for heart failure and the currently recommended pharmacological therapies for heart failure. We also highlight the effects of anti-diabetic medications on heart failure.

Association between Low-Density Lipoprotein Cholesterol Level and Cardiovascular Outcomes in Korean Adults: A Nationwide Cohort Study

BACKGROUND

To validate the treatment target of low-density lipoprotein cholesterol (LDL-C) level according to the cardiovascular disease (CVD) risk which was recommended by Korean dyslipidemia guideline.

METHODS

We used the Korean National Health Insurance Service database which included 3,958,048 people aged 20 to 89 years who underwent regular health screening. The primary outcome was incident CVD, defined as a composite of myocardial infarction and stroke during the follow-up period from 2009 to 2018.

RESULTS

The risk of CVD increased from LDL-C level of 70 mg/dL in very high-risk and high-risk groups and from 130 mg/dL in moderate-risk and low-risk groups. Adjusted hazard ratios (HRs) of LDL-C ranges 70-99, 100-129, 130-159, 160-189, and ≥190 mg/dL were 1.20 (95% confidence interval [CI], 1.08-1.33), 1.27 (1.15-1.42), 1.39 (1.23-1.56), 1.69 (1.45-1.96), and 1.84 (1.49- 2.27) in very high-risk group, and 1.07 (1.02-1.13), 1.16 (1.10-1.21), 1.29 (1.22-1.36), 1.45 (1.36-1.55), and 1.73 (1.58-1.90) in high-risk group. Adjusted HRs (95% CI) of LDL-C ranges 130-159, 160-189, and ≥190 mg/dL were 1.15 (1.11-1.20), 1.28 (1.22- 1.34), and 1.45 (1.36-1.54) in moderate-risk group and 1.07 (1.02-1.13), 1.20 (1.13-1.26), and 1.47 (1.37-1.57) in low-risk group.

CONCLUSION

We confirmed the incidence of CVD was increased in higher LDL-C range. The risk of CVD increased from ≥70 mg/dL of LDL-C in very high-risk and high-risk groups, and from ≥130 mg/dL of LDL-C in moderate-risk and low-risk groups in Korean adults.

Lipid Management in Korean People With Type 2 Diabetes Mellitus: Korean Diabetes Association and Korean Society of Lipid and Atherosclerosis Consensus Statement

Dyslipidemia in patients with diabetes is an important treatment target as a modifiable risk factor for cardiovascular disease (CVD). Although the primary treatment goal for dyslipidemia is to control low-density lipoprotein cholesterol (LDL-C), achieving this goal remains suboptimal according to recent studies. It is important to set the target goal for LDL-C control based on an accurate risk assessment for CVD. Here, we summarize the latest evidence on lipid management in patients with diabetes and present a consensus of the Korean Diabetes Association and Korean Society of Lipid and Atherosclerosis on the treatment goals of LDL-C according to the duration of diabetes, presence of CVD, target organ damage, or major cardiovascular risk factors. In patients with type 2 diabetes mellitus (T2DM) and CVD, an LDL-C goal of <55 mg/dL and a reduction in LDL-C level by 50% or more from the baseline is recommended. For the primary prevention of CVD in patients with T2DM with a duration of diabetes ≥10 years, major cardiovascular risk factors, or target organ damage, an LDL-C goal of <70 mg/dL is recommended. In patients with T2DM with a duration of diabetes <10 years and no major cardiovascular risk factors, an LDL-C goal of <100 mg/dL is recommended.

Diabetes screening in South Korea: a new estimate of the number needed to screen to detect diabetes

BACKGROUND/AIMS

The Korean Diabetes Association (KDA) guidelines recommend adults aged ≥ 40 years and adults aged ≥ 30 years with diabetes risk factors for diabetes screening. This study aimed to determine the age threshold for diabetes screening in Korean adults.

METHODS

This study was based on the analyses of Korean adults aged ≥ 20 years using the Korea National Health and Nutrition Examination Survey (KNHANES) and the National Health Insurance Service-National Sample Cohort (NHIS-NSC). To evaluate screening effectiveness, we calculated the number needed to screen (NNS).

RESULTS

NNS to detect diabetes decreased from 63 to 34 in the KNHANES and from 71 to 42 in the NHIS-NSC between the ages of 30-34 and 35-39. When universal screening was applied to adults aged ≥ 35, the NNS was similar to that of adults aged ≥ 40. Compared to the KDA guidelines, the rate of missed screening positive in adults aged ≥ 20 decreased from 4.0% to 0.2% when the newly suggested screening criteria were applied.

CONCLUSION

Universal screening for adults aged ≥ 35 and selective screening for adults aged 20 to 34, considering diabetes risk factors, may be appropriate for detecting prediabetes and diabetes in South Korea.

Machine learning models to predict the maximum severity of COVID-19 based on initial hospitalization record

Background

As the worldwide spread of coronavirus disease 2019 (COVID-19) continues for a long time, early prediction of the maximum severity is required for effective treatment of each patient.

Objective

This study aimed to develop predictive models for the maximum severity of hospitalized COVID-19 patients using artificial intelligence (AI)/machine learning (ML) algorithms.

Methods

The medical records of 2,263 COVID-19 patients admitted to 10 hospitals in Daegu, Korea, from February 18, 2020, to May 19, 2020, were comprehensively reviewed. The maximum severity during hospitalization was divided into four groups according to the severity level: mild, moderate, severe, and critical. The patient's initial hospitalization records were used as predictors. The total dataset was randomly split into a training set and a testing set in a 2:1 ratio, taking into account the four maximum severity groups. Predictive models were developed using the training set and were evaluated using the testing set. Two approaches were performed: using four groups based on original severity levels groups (i.e., 4-group classification) and using two groups after regrouping the four severity level into two (i.e., binary classification). Three variable selection methods including randomForestSRC were performed. As AI/ML algorithms for 4-group classification, GUIDE and proportional odds model were used. For binary classification, we used five AI/ML algorithms, including deep neural network and GUIDE.

Results

Of the four maximum severity groups, the moderate group had the highest percentage (1,115 patients; 49.5%). As factors contributing to exacerbation of maximum severity, there were 25 statistically significant predictors through simple analysis of linear trends. As a result of model development, the following three models based on binary classification showed high predictive performance: (1) Mild vs. Above Moderate, (2) Below Moderate vs. Above Severe, and (3) Below Severe vs. Critical. The performance of these three binary models was evaluated using AUC values 0.883, 0.879, and, 0.887, respectively. Based on results for each of the three predictive models, we developed web-based nomograms for clinical use (http://statgen.snu.ac.kr/software/nomogramDaeguCovid/).

Conclusions

We successfully developed web-based nomograms predicting the maximum severity. These nomograms are expected to help plan an effective treatment for each patient in the clinical field.

Screening for Prediabetes and Diabetes in Korean Nonpregnant Adults: A Position Statement of the Korean Diabetes Association, 2022

Diabetes screening serves to identify individuals at high-risk for diabetes who have not yet developed symptoms and to diagnose diabetes at an early stage. Globally, the prevalence of diabetes is rapidly increasing. Furthermore, obesity and/or abdominal obesity, which are major risk factors for type 2 diabetes mellitus (T2DM), are progressively increasing, particularly among young adults. Many patients with T2DM are asymptomatic and can accompany various complications at the time of diagnosis, as well as chronic complications develop as the duration of diabetes increases. Thus, proper screening and early diagnosis are essential for diabetes care. Based on reports on the changing epidemiology of diabetes and obesity in Korea, as well as growing evidence from new national cohort studies on diabetes screening, the Korean Diabetes Association has updated its clinical practice recommendations regarding T2DM screening. Diabetes screening is now recommended in adults aged ≥35 years regardless of the presence of risk factors, and in all adults (aged ≥19) with any of the risk factors. Abdominal obesity based on waist circumference (men ≥90 cm, women ≥85 cm) was added to the list of risk factors.

Sex, menopause, and age differences in the associations of persistent organic pollutants with thyroid hormones, thyroxine-binding globulin, and peripheral deiodinase activity: A cross-sectional study of the general Korean adult population

Persistent organic pollutants (POPs) can disrupt the thyroid hormone system in humans. We assessed the associations of several POPs with serum thyroid hormones (T3 and T4) and thyroid-stimulating hormone, and investigated the modulating effects of sex, menopausal status, and age on these associations, in a subgroup of the adult population (n = 1250) from the Korean National Environmental Health Survey. PCB105 and PCB118 were negatively associated with total T4 in premenopausal females and males aged <50, whereas the associations were insignificant in other groups. PCB180, p,p'-DDE, and p,p'-DDT showed positive associations with total T3 in postmenopausal females; however, among males aged ≥50, PCB118, PCB138, and p,p'-DDE showed negative associations with total T3. The effects of exposure to multiple POPs were examined in multi-factor analyses. Factor 2 comprised PCB52, hexachlorobenzene, and BDE-47 was associated with an increase in free T4 in premenopausal females (β = 0.015, p = 0.024), while Factor 1, which contained most POPs, was associated with a change in total T3 in postmenopausal females (β = 0.032, p = 0.040) and males aged ≥50 (β = -0.039, p = 0.023). Changes in total T4 or total T3 could be explained by differences in thyroxine-binding globulin (TBG) and peripheral deiodinase activity (G_D). Negative associations of TBG with PCB105 in premenopausal females and PCB153 in males aged <50 may mediate the effect of decreasing total T4. PCB180, p,p'-DDE, p,p'-DDT, and Factor 1 were positively associated with G_D, which is consistent with an increased total T3 in postmenopausal females. PCB118 was negatively associated with G_D and total T3 in males aged ≥50. BDE-47 and β-hexachlorocyclohexane were associated with thyroid autoantibodies in premenopausal females and males aged <50. Our observations suggest that the thyroid-disrupting effects of POPs may differ by sex, sex hormonal status, and age, and may be mediated by TBG and G_D.

Real-World Prescription Patterns and Barriers Related to the Use of Sodium-Glucose Cotransporter 2 Inhibitors among Korean Patients with Type 2 Diabetes Mellitus and Cardiovascular Disease

BACKGROUND

To evaluate prescription trends and clinical factors of the sodium-glucose cotransporter 2 inhibitors (SGLT2i) use according to the presence of atherosclerotic cardiovascular disease (ASCVD) or heart failure (HF) in Korean patients with type 2 diabetes mellitus (T2DM).

METHODS

Prescription patterns of SGLT2i use between 2015 and 2019 were determined using the Korean National Health Insurance Service database of claims.

RESULTS

Of all patients with T2DM (n=4,736,493), the annual prescription rate of SGLT2i increased every year in patients with ASCVD (from 2.2% to 10.7%) or HF (from 2.0% to 11.1%). After the first hospitalization for ASCVD (n=518,572), 13.7% (n=71,259) of patients initiated SGLT2i with a median of 10.6 months. After hospitalization for HF (n=372,853), 11.2% (n=41,717) of patients initiated SGLT2i after a median of 8.8 months. In multivariate regression for hospitalization, older age (per 10 years, odds ratio [OR], 0.57; 95% confidence interval [CI], 0.56 to 0.57), lower household income (OR, 0.93; 95% CI, 0.92 to 0.95), rural residents (OR, 0.95; 95% CI, 0.93 to 0.97), and dipeptidyl peptidase-4 inhibitor (DPP-4i) users (OR, 0.82; 95% CI, 0.81 to 0.84) were associated with lesser initiation of SGLT2i in ASCVD. Additionally, female gender (OR, 0.97; 95% CI, 0.95 to 0.99) was associated with lesser initiation of SGLT2i in HF.

CONCLUSION

The prescription rate of SGLT2i increased gradually up to 2019 but was suboptimal in patients with ASCVD or HF. After the first hospitalization for ASCVD or HF, older age, female gender, low household income, rural residents, and DPP-4i users were less likely to initiate SGLT2i.

Prevalence of Diabetic Retinopathy in Undiagnosed Diabetic Patients: A Nationwide Population-Based Study

BACKGROUND

We investigated the prevalence of diabetic retinopathy (DR) in patients with undiagnosed diabetes through a nationwide survey, compared to those with known diabetes.

METHODS

Among the participants of the Korean National Health and Nutrition Examination Surveys (KNHANES) from 2017 to 2018, individuals aged ≥40 years with diabetes and fundus exam results were enrolled. Sampling weights were applied to represent the entire Korean population. Newly detected diabetes patients through KNHANES were classified under "undiagnosed diabetes."

RESULTS

Among a total of 9,108 participants aged ≥40 years, 951 were selected for analysis. Of them, 31.3% (standard error, ±2.0%) were classified under "undiagnosed diabetes." The prevalence of DR in patients with known and undiagnosed diabetes was 24.5%±2.0% and 10.7%±2.2%, respectively (P<0.001). The DR prevalence increased with rising glycosylated hemoglobin (HbA1c) levels in patients with known and undiagnosed diabetes (P for trend=0.001 in both). Among those with undiagnosed diabetes, the prevalence of DR was 6.9%±2.1%, 8.0%±3.4%, 5.6%±5.7%, 16.7%±9.4%, and 42.6%±14.8% for HbA1c levels of <7.0%, 7.0%-7.9%, 8.0%-8.9%, 9.0%-9.9%, and ≥10.0% respectively. There was no difference in the prevalence of hypertension, dyslipidemia, hypertriglyceridemia, or obesity according to the presence or absence of DR.

CONCLUSION

About one-third of patients with diabetes were unaware of their diabetes, and 10% of them have already developed DR. Considering increasing the prevalence of DR according to HbA1c level was found in patients with undiagnosed diabetes like those with known diabetes, screening and early detection of diabetes and DR are important.

Integrative Pathway Analysis of SNP and Metabolite Data Using a Hierarchical Structural Component Model

Integrative multi-omics analysis has become a useful tool to understand molecular mechanisms and drug discovery for treatment. Especially, the couplings of genetics to metabolomics have been performed to identify the associations between SNP and metabolite. However, while the importance of integrative pathway analysis is increasing, there are few approaches to utilize pathway information to analyze phenotypes using SNP and metabolite. We propose an integrative pathway analysis of SNP and metabolite data using a hierarchical structural component model considering the structural relationships of SNPs, metabolites, pathways, and phenotypes. The proposed method utilizes genome-wide association studies on metabolites and constructs the genetic risk scores for metabolites referred to as genetic metabolomic scores. It is based on the hierarchical model using the genetic metabolomic scores and pathways. Furthermore, this method adopts a ridge penalty to consider the correlations between genetic metabolomic scores and between pathways. We apply our method to the SNP and metabolite data from the Korean population to identify pathways associated with type 2 diabetes (T2D). Through this application, we identified well-known pathways associated with T2D, demonstrating that this method adds biological insights into disease-related pathways using genetic predispositions of metabolites.

Lead, mercury, and cadmium exposures are associated with obesity but not with diabetes mellitus: Korean National Environmental Health Survey (KoNEHS) 2015-2017

BACKGROUND

Associations of heavy metal exposures with obesity and obesity-related traits have been suggested, while those with nonalcoholic fatty liver disease (NAFLD) and diabetes mellitus (DM) are often inconsistent.

METHODS

This study included 3787 adults aged ≥19 years who participated in the Korean National Environmental Health Survey 2015-2017, and investigated the association of toxic heavy metals with metabolic diseases. Lead (Pb), mercury (Hg), and cadmium (Cd) were measured either in urine (uHg, uCd) or total blood (bPb, bHg). Body mass index (BMI) was calculated, and DM cases were identified through a self-answered medication history. Hepatic Steatosis Index (HSI) as a surrogating index of NAFLD, was calculated using hepatic enzyme measurements, including aspartate aminotransferase (AST) and alanine aminotransferase (ALT).

RESULTS

Adults in the highest quartile of bPb, bHg, and uHg showed significantly elevated odds of obesity (BMI ≥25 kg/m²), compared to the lowest quartile (OR 1.58 for bPb, 1.92 for bHg, and 1.81 for uHg). HSI was positively correlated with bHg, uHg, and uCd concentrations. The odds of NAFLD (HSI ≥36) were also increased with increasing quartile of bHg, uHg, and uCd concentrations. For DM, bPb showed a significant negative association, while bHg and uCd exhibited non-monotonic and inconclusive associations.

CONCLUSIONS

Among the general adult population of Korea, both Pb and Hg exposures were associated with an increased risk of obesity. In addition, both Hg and Cd exposures were associated with increased odds of NAFLD. These metals, however, were not associated with an increased risk of DM.

Muscle strength, an independent determinant of glycemic control in older adults with long-standing type 2 diabetes: a prospective cohort study

Background

Although the proportion of older patients with type 2 diabetes mellitus (T2DM) has increased, few studies have reported the factors affecting glucose levels in older patients with long-standing T2DM. This study assessed the determinants of glycemic control in older adults with T2DM of a duration of ≥10 years, including muscle mass, muscle quality, and β-cell function.

Methods

This was a prospective study of older patients aged ≥60 years with a T2DM duration of ≥10 years. The Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index, handgrip strength (HGS), and body composition through bioelectrical impedance analysis were assessed. The primary outcome was a composite of: (i) increment of glycated hemoglobin (HbA1c) from the baseline ≥0.6% and (ii) HbA1c ≥ 9% at any time point during the follow-up period. To find the predicting determinants of the outcome, we performed the Cox proportional hazard analysis.

Results

Among 100 patients (mean age, 64.0 ± 8.6 years; median duration of diabetes, 20 [interquartile range (IQR), 17–23] years; median HbA1c at baseline, 7.1 [IQR, 6.7–7.4] %), the primary outcome was observed in 40 (40.0%) patients during 4.0 (IQR 2.3–5.0) years of follow-up. A Cox proportional hazards model adjusted for age, sex, baseline HbA1c, obesity, duration of DM and anti-diabetic medication at baseline showed that low HGS and insulin resistance at the baseline were independent determinants of the primary outcome (hazard ratio [HR] = 2.23 [95% confidence interval (CI), 1.06–4.72] and 2.39 [95% CI, 1.18–4.83], respectively). Sex stratification confirmed that HGS and muscle mass were independent determinants of the primary outcome only in women (HR per quartile, 0.58 [95% CI, 0.37–0.93] and 0.46 [95% CI, 0.25–0.85], respectively). `.

Conclusions

Low HGS and insulin resistance were independent risk factors for aggravated glycemic control among older patients with long standing T2DM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02629-5.

Contribution of hypertriglyceridemia to ischemic cardiovascular disease in Korean Women: A nationwide population-based study

BACKGROUND

The independent effect of serum triglyceride levels on the development of ischemic cardiovascular disease (CVD) remains inconclusive, which might be due to heterogeneity among study populations.

OBJECTIVE

To evaluate the effect of triglyceride levels on ischemic CVD and mortality in Korean women, with stratification according to the menopausal status, diabetes mellitus, or low-density lipoprotein cholesterol levels (LDL-C).

METHODS

We retrospectively investigated Korean women aged 40-69 years who underwent health examination in 2009 and were followed up until 2018 using nationwide claim data. The subjects were divided according to triglyceride quartiles (Q): Q1 <70 mg/dL, Q2 71-99 mg/dL, Q3 100-142 mg/dL, and Q4 ≥143 mg/dL. The primary outcome was the incidence of CVD defined as a composite of myocardial infarction and ischemic stroke.

RESULTS

Among 2,208,347 women, primary outcome occurred in 62,255 (2.8%) subjects. As triglyceride levels increased, the event rate of primary outcome increased in both premenopausal and postmenopausal women in the fully adjusted model (hazard ratio [HR] per 1 Q, 1.10 [95% confidence interval (CI), 1.08-1.12] and 1.08 [95% CI, 1.07-1.09], respectively), which was maintained on further stratification according to diabetes or LDL-C (P<0.05 in all). Higher triglyceride levels were more significantly associated with the primary outcome, MI, and stroke risk among women with optimal non-high-density lipoprotein cholesterol levels (non-HDL-C) <130 mg/dL, but only weakly with stroke for women with non-optimal non-HDL-C.

CONCLUSION

Triglyceride is an independent prognosticator in the development of ischemic CVD in Korean women aged 40-69 years.

Brain Structural Alterations, Diabetes Biomarkers, and Cognitive Performance in Older Adults With Dysglycemia

Despite the high risk of dementia in older adults with type 2 diabetes, the neuroanatomical correlates of cognitive dysfunction that are particularly affected by diabetes are not well characterized. This study is aimed to examine the structural brain alterations in dysglycemic older adults. Using voxel-based morphometric and tract-based spatial statistics, we examined changes in gray matter volume, white matter volume, and microstructural integrity in older adults with prediabetes and diabetes. We also assessed the correlation of these structural changes with diabetes biomarkers and cognitive performance. A total of 74 non-demented older adults (normal, n = 14; prediabetes, n = 37; and diabetes, n = 23) participated in this study and underwent structural and diffusion magnetic resonance imaging (MRI) scans and neuropsychological tests. Subjects with diabetes showed reduced volume of cerebellar gray matter and frontal white matter and diffuse white matter dysintegrity, while those with prediabetes only showed reduced volume of insular gray matter. Atrophic changes in the cerebellum and frontal lobe and frontal white matter dysintegrity were correlated with chronic hyperglycemia and insulin resistance and worse performance in verbal memory recognition and executive function tests. Our findings suggest that chronic hyperglycemia and insulin resistance may alter brain structures forming the fronto-cerebellar network, which may cause cognitive dysfunction in older adults.

Cardiovascular Outcomes of Obesity According to Menopausal Status: A Nationwide Population-Based Study

BACKGROUND

We estimated the effect of obesity on the incidence of cardiovascular disease (CVD) and mortality in women according to menopausal status.

METHODS

Women aged 40 to 69 years under routine health check-ups provided by the National Health Insurance Service in 2009 were followed up till 2018 (n=2,208,559).

RESULTS

In premenopausal women, a significant increment of mortality rate was found in underweight and obesity class II (hazard ratio [HR], 1.48; 95% confidence interval [CI], 1.31 to 1.67; and HR, 1.25; 95% CI, 1.12 to 1.39) compared to normal body mass index (BMI); overweight and obesity class I did not affect mortality rate. In postmenopausal women, obesity as well as overweight status reduced the risk of mortality compared to normal BMI (HR, 0.86; 95% CI, 0.83 to 0.88; and HR, 0.84; 95% CI, 0.82 to 0.86). By contrast, there was a linear association between CVD and BMI above the normal range irrespective of menopausal status, which was attenuated in diabetic women.

CONCLUSION

The current study replicated the J-shaped relationship between BMI and mortality, being more prominent in the postmenopausal group. The risk of CVD was linearly increased as BMI was increased above the normal range irrespective of menopausal status.

Lipid Profiles in Primary Aldosteronism Compared with Essential Hypertension: Propensity-Score Matching Study

BACKGROUND

There has been controversy regarding the association between primary aldosteronism (PA) and dyslipidemia and few studies considered the effects of diabetes and renal function on lipid metabolism. We analyzed lipid profiles of PA patients and compared them to propensity-score (PS)-matched essential hypertension (EH) patients adjusting for glycemic status and renal function.

METHODS

Patients who were diagnosed with PA using a saline-infusion test at Seoul National University Hospital from 2000 to 2018 were retrospectively analyzed. EH patients who had aldosterone-renin ratio (ARR) results were selected as controls. Covariates, including diabetes, were PS-matched for patients with PA, lateralized PA, non-lateralized PA, and high ARR to EH patients, respectively.

RESULTS

Among a total of 80 PA and 80 EH patients, total cholesterol (TC) and triglyceride (TG) levels were significantly lower in the PA patients than in the EH patients (least-squares mean±standard error: 185.5±4.4 mg/dL vs. 196.2±4.4 mg/dL, P=0.047, for TC; and 132.3±11.5 mg/dL vs. 157.4±11.4 mg/dL, P=0.035, for TG) in fully adjusted model (adjusting for multiple covariates, including diabetes status, glycosylated hemoglobin level, and estimated glomerular filtration rate). There were no significant differences in high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol levels between the two groups. According to increments in aldosterone levels, an increasing tendency of HDL-C and decreasing tendencies of TG and non-HDL-C were observed.

CONCLUSION

PA patients had lower TC and TG levels than EH patients, independent of glycemic status and renal function.

2021 Clinical Practice Guidelines for Diabetes Mellitus of the Korean Diabetes Association

The Committee of Clinical Practice Guidelines of the Korean Diabetes Association (KDA) updated the previous clinical practice guidelines for Korean adults with diabetes and prediabetes and published the seventh edition in May 2021. We performed a comprehensive systematic review of recent clinical trials and evidence that could be applicable in real-world practice and suitable for the Korean population. The guideline is provided for all healthcare providers including physicians, diabetes experts, and certified diabetes educators across the country who manage patients with diabetes or the individuals at the risk of developing diabetes mellitus. The recommendations for screening diabetes and glucose-lowering agents have been revised and updated. New sections for continuous glucose monitoring, insulin pump use, and non-alcoholic fatty liver disease in patients with diabetes mellitus have been added. The KDA recommends active vaccination for coronavirus disease 2019 in patients with diabetes during the pandemic. An abridgement that contains practical information for patient education and systematic management in the clinic was published separately.

Current Status of Low-Density Lipoprotein Cholesterol Target Achievement in Patients with Type 2 Diabetes Mellitus in Korea Compared with Recent Guidelines

BACKGROUND

We evaluated the achievement of low-density lipoprotein cholesterol (LDL-C) targets in patients with type 2 diabetes mellitus (T2DM) according to up-to-date Korean Diabetes Association (KDA), European Society of Cardiology (ESC)/European Atherosclerosis Society (EAS), and American Diabetes Association (ADA) guidelines.

METHODS

This retrospective cohort study collected electronic medical record data from patients with T2DM (≥20 years) managed by endocrinologists from 15 hospitals in Korea (January to December 2019). Patients were categorized according to guidelines to assess LDL-C target achievement. KDA (2019): Very High-I (atherosclerotic cardiovascular disease [ASCVD]) <70 mg/dL; Very High-II (target organ damage [TOD], or cardiovascular risk factors [CVRFs]) <70 mg/dL; high (others) <100 mg/dL. ESC/EAS (2019): Very High-I (ASCVD): <55 mg/dL; Very High-II (TOD or ≥3-CVRF) <55 mg/dL; high (diabetes ≥10 years without TOD plus any CVRF) <70 mg/dL; moderate (diabetes <10 years without CVRF) <100 mg/dL. ADA (2019): Very High-I (ASCVD); Very High-II (age ≥40+ TOD, or any CVRF), for high intensity statin or statin combined with ezetimibe.

RESULTS

Among 2,000 T2DM patients (mean age 62.6 years; male 55.9%; mean glycosylated hemoglobin 7.2%) ASCVD prevalence was 24.7%. Of 1,455 (72.8%) patients treated with statins, 73.9% received monotherapy. According to KDA guidelines, LDL-C target achievement rates were 55.2% in Very High-I and 34.9% in Very High-II patients. With ESC/EAS guidelines, target attainment rates were 26.6% in Very High-I, 15.7% in Very High-II, and 25.9% in high risk patients. Based on ADA guidelines, most patients (78.9%) were very-high risk; however, only 15.5% received high-intensity statin or combination therapy.

CONCLUSION

According to current dyslipidemia management guidelines, LDL-C goal achievement remains suboptimal in Korean patients with T2DM.

Prediction Models for the Clinical Severity of Patients With COVID-19 in Korea: Retrospective Multicenter Cohort Study

BACKGROUND

Limited information is available about the present characteristics and dynamic clinical changes that occur in patients with COVID-19 during the early phase of the illness.

OBJECTIVE

This study aimed to develop and validate machine learning models based on clinical features to assess the risk of severe disease and triage for COVID-19 patients upon hospital admission.

METHODS

This retrospective multicenter cohort study included patients with COVID-19 who were released from quarantine until April 30, 2020, in Korea. A total of 5628 patients were included in the training and testing cohorts to train and validate the models that predict clinical severity and the duration of hospitalization, and the clinical severity score was defined at four levels: mild, moderate, severe, and critical.

RESULTS

Out of a total of 5601 patients, 4455 (79.5%), 330 (5.9%), 512 (9.1%), and 301 (5.4%) were included in the mild, moderate, severe, and critical levels, respectively. As risk factors for predicting critical patients, we selected older age, shortness of breath, a high white blood cell count, low hemoglobin levels, a low lymphocyte count, and a low platelet count. We developed 3 prediction models to classify clinical severity levels. For example, the prediction model with 6 variables yielded a predictive power of >0.93 for the area under the receiver operating characteristic curve. We developed a web-based nomogram, using these models.

CONCLUSIONS

Our prediction models, along with the web-based nomogram, are expected to be useful for the assessment of the onset of severe and critical illness among patients with COVID-19 and triage patients upon hospital admission.

Incidence and disease course of new-onset diabetes mellitus in breast and colorectal cancer patients undergoing chemotherapy: A prospective multicenter cohort study

AIMS

To investigate the incidence of and risk factors for new-onset type 2 diabetes mellitus (DM) developed during chemotherapy that included steroids in cancer patients without DM.

METHODS

This multicenter, prospective, and observational cohort study enrolled 299 cancer patients without DM (aged > 18 years), planning 4-8 cycles of adjuvant chemotherapy. The endpoints were the incidence, remission rate, and independent determinants of new-onset DM during chemotherapy.

RESULTS

Between April 2015 and March 2018, 270 subjects with colorectal cancer or breast cancer (mean age, 51.0 years) completed the follow up (mean 39 months). Of whom, 17 subjects (6.3%) developed DM within a median time of 90 days (range, 17-359 days). Male sex (hazard ratio [HR], 15.839; 95% confidence interval [CI], 2.004-125.20) and impaired fasting glucose (IFG) at baseline (HR, 8.307; CI, 1.826-37.786) were independent risk factors. Six months after chemotherapy completion, 11/17 subjects (64.7%) experienced DM remission, associated with a significantly higher C-peptide level at baseline (C-peptide levels, 1.3 ng/mL in subjects with remission and 0.9 ng/mL in subjects without remission, age- and sex-adjusted P = 0.007).

CONCLUSIONS

DM incidence was 6.3% in patients who received chemotherapy with dexamethasone. Close monitoring for hyperglycemia is recommended, especially for men with IFG.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03062072).

Association of exposure to polycyclic aromatic hydrocarbons and heavy metals with thyroid hormones in general adult population and potential mechanisms

Air pollution and fuel emissions are the common sources of human exposure to polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Several studies have suggested potential associations between PAHs/heavy metals and thyroid hormones, however, reports have been inconsistent. In this study, we employed a subpopulation of the adults (n = 1254) who participated in the Korean National Environmental Health Survey 2015-2017, and investigated the association of PAHs and major heavy metals with thyroid hormones, and explored the underlying mechanisms of thyroid disruption. Four PAH metabolites and three heavy metals of lead (Pb), mercury (Hg), and cadmium (Cd) were measured either in urine or in total blood. In addition, thyroid hormones (T3 and T4), TSH, thyroxine-binding globulin (TBG), and thyroid autoantibodies were measured, and peripheral deiodinase activity (G_D) and thyroid's secretory capacity (G_T) were calculated. Urinary Hg was negatively associated with total T3 in both males and females, while it was positively associated with total T4 among females only. Urinary Hg was related to decreased G_D and increased G_T in both sexes. In contrast, urinary Cd was positively associated with total T3 and G_D in both male and female populations. Urinary Cd also showed a positive association with thyroid autoantibodies, but only in males. A multi-factor model considering co-exposure to multiple chemicals also resulted in similar associations. Among the measured PAH metabolites, only urinary 1-hydroxypyrene showed a negative association with total T3 in males. However, this association was marginal, and disappeared in a multi-chemical model. The present observations are suggestive that exposures to Hg and Cd might disrupt thyroid hormones, possibly through an alteration of deiodinase activity. Association of PAH exposure with thyroid hormone appears to be insignificant.

Hypertriglyceridemia Is an Independent Risk Factor for Cardiovascular Diseases in Korean Adults Aged 30-49 Years: a Nationwide Population-Based Study

Objective

This study was conducted to estimate the incidence of cardiovascular disease (CVD) independently from low-density lipoprotein (LDL) cholesterol according to triglyceride (TG) levels in young adults.

Methods

Subjects aged 30–49 years with data from routine health check-ups provided by the National Health Insurance Service during 2009 were selected. The primary outcome was incident CVD, defined as a composite of ischemic heart disease and ischemic stroke during the follow-up period from 2009 to 2018.

Results

The mean age of study subjects (n=1,823,537) was 40.1±5.7 years, and the median follow-up period was 8.3 years. The quartiles of serum TG levels at the baseline were calculated: Q1, <74 mg/dL; Q2, 74–108 mg/dL; Q3, 109–166 mg/dL; and Q4: >166 mg/dL. The highest quartile of TG levels (Q4) had a significantly higher risk of the primary outcome than Q1 (hazard ratio [HR], 2.40 [95% confidence interval; CI, 2.33–2.47]). Q2 and Q3 also experienced the primary outcome more frequently than Q1 (HR, 1.37 [95% CI, 1.33–1.42] and HR, 1.80 [95% CI, 1.75–1.86], respectively). Even after adjustment for age, sex, obesity, alcohol drinking amount, smoking, LDL cholesterol, diabetes mellitus, hypertension, lipid-lowering medication use, and family history of CVD, there was a significant dose-response relationship between TG quartiles and the risk of the primary outcome (HR per quartile, 1.13 [95% CI, 1.12–1.14]).

Conclusion

In conclusion, in the Korean population aged 30–49 years, high TG levels independently increased future CVD risk in both men and women.

Associations of urinary concentrations of phthalate metabolites, bisphenol A, and parabens with obesity and diabetes mellitus in a Korean adult population: Korean National Environmental Health Survey (KoNEHS) 2015-2017

Phthalates and bisphenol A (BPA) have been suspected as risk factors for obesity and diabetes mellitus (DM) among humans. However, associations between phthalates and environmental phenols are often inconsistent across different populations. In this study, we recruited the adult population (n = 3782) of the Korean National Environmental Health Survey (KoNEHS) 2015-2017 (Cycle 3) and assessed the associations between urinary biomarkers of phthalate, BPA, and paraben exposure with obesity and DM. A potential collider issue with the use of urinary creatinine (Cr) or specific gravity (SG) exists when adjusting urinary dilution; therefore, a covariate-adjusted standardization (CAS) was employed for adjustment, and the results were compared. In the present population, the direction of the association often varied depending on the choices made to adjust urinary dilution. When using CAS, the direction of association resembled those of previously reported experimental observations. With Cr or SG adjustment, ORs for obesity decreased in the highest quartiles of monocarboxyoctyl phthalate (MCOP) [OR (95% CI) = Cr: 0.71 (0.54, 0.93); SG: 0.68 (0.52, 0.90)], monocarboxy-isononyl phthalate (MCNP) [OR (95% CI) = Cr: 0.67 (0.52, 0.87); SG: 0.68 (0.52, 0.89)], and mono(3-carboxylpropyl) phthalate (MCPP) in the urine [OR (95% CI) = Cr: 0.60 (0.47, 0.76); SG: 0.61 (0.48, 0.77)]; however, with CAS, these negative associations disappeared. Instead, mono-benzyl phthalate (MBzP) [OR (95% CI) = 1.31 (1.03, 1.66)], BPA [OR (95% CI) = 1.62 (1.27, 2.06)], or ethyl paraben (EtP) [OR (95% CI) = 1.51 (1.19, 1.91)] concentrations in the highest quartile showed positive associations with a higher risk of obesity. On the other hand, for DM, an overall decrease in ORs was observed for phthalate metabolites and BPA following SG adjustment and disappeared with CAS adjustment. In addition, the highest quartiles of BPA, methyl paraben (MeP), and ethyl paraben (EtP) showed a significantly higher risk of DM than those in the lowest quartiles following CAS [OR (95% CI) = BPA: 1.65 (1.06, 2.59); MeP: 1.68 (1.08, 2.60); and EtP: 2.74 (1.77, 4.24), respectively]. The present observations outline the importance of using an appropriate adjustment method for urinary dilution in association studies on obesity and DM. In addition, several phthalates, BPA, and parabens were identified as potential chemical risk factors for these outcomes. Further studies are warranted in other populations to confirm these observations.

Association between muscle strength and advanced fibrosis in non-alcoholic fatty liver disease: a Korean nationwide survey

BACKGROUND

We investigated the association between muscle strength and the prevalence of advanced fibrosis among individuals with non-alcoholic fatty liver disease (NAFLD) using a nationwide cross-sectional survey.

METHODS

Individuals, 20 to 79 years of age, from the Korean National Health and Nutrition Examination Surveys (KNHANES) from 2014 to 2016 were selected (N = 14 861), with sample weights applied. Muscle strength was quantified as the handgrip strength divided by the body mass index (BMI); low muscle strength (LMS) was defined as the lowest quartile (Q₁ ) of the handgrip strength/BMI for our sample population. NAFLD was defined as hepatic steatosis index >36. Advanced fibrosis was defined as a fibrosis-4 index score ≥1.30 (Fibrosis_FIB4 ).

RESULTS

The mean age of the study population was 45.6 ± 0.2 years, and 42.4% were male. As muscle strength increased, the mean BMI and age decreased accordingly, and the proportions of diabetes, dyslipidaemia, hypertension, and obesity decreased significantly (P < 0.001 for all). In a crude analysis, the LMS was associated with an increased prevalence of NAFLD (odds ratio [OR] 3.62, 95% confidence interval [CI] 3.25-4.03, P < 0.001), which remained significant even after adjustment for age, sex, obesity, insulin resistance, diabetes, hypertension, dyslipidaemia, and high-sensitivity C-reactive protein (OR 1.66, 95% CI 1.28-2.16, P < 0.001). In this logistic regression model, the prevalence of NAFLD decreased by 24% with each quartile increment in muscle strength (OR 0.76, 95% CI 0.68-0.85, P < 0.001). Among individuals with NAFLD (n = 2092), LMS was significantly associated with the presence of advanced fibrosis (Fibrosis_FIB4 ) independently of age, sex, obesity, diabetes, hypertension, dyslipidaemia, and high-sensitivity C-reactive protein (OR 1.66, 95% CI 1.01-2.49, P = 0.015), which lost its statistical significance after additional adjustment for insulin resistance.

CONCLUSIONS

Low muscle strength is independently associated with NAFLD. The significant association between LMS and advanced fibrosis in NAFLD may be mediated through insulin resistance.

Sodium-glucose cotransporter-2 inhibitor for renal function preservation in patients with type 2 diabetes mellitus: A Korean Diabetes Association and Korean Society of Nephrology consensus statement

Diabetes is a leading cause of end-stage renal disease. Therefore, prevention of renal dysfunction is an important treatment goal in the management of diabetes. The data of landmark cardiovascular outcome trials of sodium-glucose cotransporter-2 (SGLT2) inhibitors showed profound reno-protective effects. The Korean Diabetes Association and the Korean Society of Nephrology reviewed clinical trials and performed a meta-analysis to assess the effects of SGLT2 inhibitors on the preservation of estimated glomerular filtration rate (eGFR). We limited the data of SGLT2 inhibitors which can be prescribed in Korea. Both eGFR value and its change from the baseline were significantly more preserved in the SGLT2-inhibitor treatment group compared to the control group after 156 weeks. However, some known adverse events were increased in SGLT2 inhibitor treatment, such as genital infection, diabetic ketoacidosis, and volume depletion. We recommend long-term use of SGLT2 inhibitors in patients with type 2 diabetes mellitus (T2DM) for attenuation of renal function decline. However, we cannot generalize our recommendations due to the lack of long-term clinical trials testing the reno-protective effects of every SGLT2 inhibitor in a broad range of patients with T2DM. This recommendation can be revised and updated after the publication of several large-scale renal outcome trials.

Plasma Clusterin as a Potential Link Between Diabetes and Alzheimer Disease

OBJECTIVE

Plasma clusterin, a promising biomarker of Alzheimer disease (AD), has been associated with diabetes mellitus (DM). However, clusterin has not been investigated considering a relationship with both DM and AD. In this study, we aimed to investigate the individual and interactive relationships of plasma clusterin levels with both diseases.

DESIGN

Cross-sectional observation study.

METHODS

We classified participants by the severity of cognitive (normal cognition, mild cognitive impairment [MCI], and AD) and metabolic (healthy control, prediabetes, and DM) impairments. We evaluated the cognitive and metabolic functions of the participants with neuropsychological assessments, brain magnetic resonance imaging, and various blood tests, to explore potential relationships with clusterin.

RESULTS

Plasma clusterin levels were higher in participants with AD and metabolic impairment (prediabetes and DM). A two-way ANCOVA revealed no synergistic, but an additive effect of AD and DM on clusterin. Clusterin was negatively correlated with cognitive scores. It was also associated with metabolic status indicated by glycated hemoglobin A1c (HbA1c), the Homeostatic Model Assessment for Insulin Resistance index, and fasting C-peptide. It showed correlations between medial temporal atrophy and periventricular white matter lesions, indicating neurodegeneration and microvascular insufficiency, respectively. Further mediation analysis to understand the triadic relationship between clusterin, AD, and DM revealed that the association between DM and AD was significant when clusterin is considered as a mediator of their relationship.

CONCLUSIONS

Clusterin is a promising biomarker of DM as well as of AD. Additionally, our data suggest that clusterin may have a role in linking DM with AD as a potential mediator.

Sodium-Glucose Cotransporter-2 Inhibitor for Renal Function Preservation in Patients with Type 2 Diabetes Mellitus: A Korean Diabetes Association and Korean Society of Nephrology Consensus Statement

Diabetes is a leading cause of end-stage renal disease. Therefore, prevention of renal dysfunction is an important treatment goal in the management of diabetes. The data of landmark cardiovascular outcome trials of sodium-glucose cotransporter-2 (SGLT2) inhibitor showed profound reno-protective effects. The Korean Diabetes Association and the Korean Society of Nephrology reviewed clinical trials and performed meta-analysis to assess the effects of SGLT2 inhibitors on the preservation of estimated glomerular filtration rate (eGFR). We limited the data of SGLT2 inhibitors which can be prescribed in Korea. Both eGFR value and its change from the baseline were significantly more preserved in the SGLT2 inhibitor treatment group compared to the control group after 156 weeks. However, some known adverse events were increased in SGLT2 inhibitor treatment, such as genital infection, diabetic ketoacidosis, and volume depletion. We recommend the long-term use SGLT2 inhibitor in patients with type 2 diabetes mellitus (T2DM) for attenuation of renal function decline. However, we cannot generalize our recommendation due to lack of long-term clinical trials testing reno-protective effects of every SGLT2 inhibitor in a broad range of patients with T2DM. This recommendation can be revised and updated after publication of several large-scale renal outcome trials.

Peripheral arterial endothelial dysfunction predicts future cardiovascular events in diabetic patients with albuminuria: a prospective cohort study

Background

Reactive hyperemia-peripheral arterial tonometry (RH-PAT) is a noninvasive and simple test for evaluating the endothelial function. There has been sparse evidence on the usefulness of the RH-PAT index (RHI) in predicting future cardiovascular diseases among diabetic patients.

Methods

Asymptomatic diabetic patients with albuminuria were selected; their medical history and laboratory findings were evaluated every 3 to 4 months, respectively. The primary outcome was a composite of three-point major adverse cardiovascular events (3-point MACE): death from cardiovascular causes, acute coronary events, or nonfatal stroke. On the contrary, secondary outcomes included a composite of 3-point MACE, hospitalization for heart failure, or chronic kidney disease (CKD) progression. RHI was measured using the Endo-PAT2000 at the baseline. RHI < 1.67 was considered to indicate peripheral endothelial dysfunction (PED).

Results

In total, 149 subjects were included (mean age, 61.8 ± 9.2 years; duration of diabetes was 12 years). During the follow-up period (median, 49.7 months), of the 149 subjects, primary outcomes were detected in 12 (1 [2.3%] and 11 [10.5%] of those without and with PED, respectively). The presence of PED in baseline measurements significantly increased both primary and secondary outcomes, following adjustment for age, sex, hypertension, glycated hemoglobin, low-density lipoprotein cholesterol, triglyceride, systolic blood pressure, baseline estimated glomerular filtration rate, overt proteinuria, duration of diabetes, premedical history of ischemic events, anti-platelet agents, and smoking history (hazard ratio [HR]: 10.95; 95% confidence interval CI 1.00–119.91 for the primary outcome; HR, 4.12; 95% CI 1.37–12.41 for secondary outcome). In addition, PED could predict secondary outcomes independent of the risk score according to the American College of Cardiology/American Heart Association (HR: 3.24; 95% CI 1.14–9.17).

Conclusions

PED can independently predict future cardiovascular events among diabetic patients with albuminuria.

Validation of Risk Prediction Models for Atherosclerotic Cardiovascular Disease in a Prospective Korean Community-Based Cohort

BACKGROUND

To investigate the performance of the 2013 American College of Cardiology/American Heart Association Pooled Cohort Equations (PCE) in a large, prospective, community-based cohort in Korea and to compare it with that of the Framingham Global Cardiovascular Disease Risk Score (FRS-CVD) and the Korean Risk Prediction Model (KRPM).

METHODS

In the Korean Genome and Epidemiology Study (KOGES)-Ansan and Ansung study, we evaluated calibration and discrimination of the PCE for non-Hispanic whites (PCE-WH) and for African Americans (PCE-AA) and compared their predictive abilities with the FRS-CVD and the KRPM.

RESULTS

The present study included 7,932 individuals (3,778 men and 4,154 women). The PCE-WH and PCE-AA moderately overestimated the risk of atherosclerotic cardiovascular disease (ASCVD) for men (6% and 13%, respectively) but underestimated the risk for women (-49% and -25%, respectively). The FRS-CVD overestimated ASCVD risk for men (91%) but provided a good risk prediction for women (3%). The KRPM underestimated ASCVD risk for men (-31%) and women (-31%). All the risk prediction models showed good discrimination in both men (C-statistic 0.730 to 0.735) and women (C-statistic 0.726 to 0.732). Recalibration of the PCE using data from the KOGES-Ansan and Ansung study substantially improved the predictive accuracy in men.

CONCLUSION

In the KOGES-Ansan and Ansung study, the PCE overestimated ASCVD risk for men and underestimated the risk for women. The PCE-WH and the FRS-CVD provided an accurate prediction of ASCVD in men and women, respectively.

A novel non-PPARgamma insulin sensitizer: MLR-1023 clinicalproof-of-concept in type 2 diabetes mellitus

AIM

MLR-1023, called Tolimidone when evaluated unsuccessfully by Pfizer for gastric ulcer disease, has been repurposed as a novel oral insulin sensitizer with its effects mediated by selective activation of Lyn kinase. We aimed to evaluate the optimal dose, efficacy and safety of MLR-1023 in patients with type 2 diabetes.

METHODS

Type 2 diabetes patients (18-75 years) on diet/exercise therapy were randomized and double-blinded to receive MLR-1023 (100-mg or 200-mg, once-daily [qd] or twice-daily [bid]) or matching placebo for 28 days. The primary endpoint was postprandial glucose (PPG) area under the curve (AUC_0-3h) in a mixed meal tolerance test (MMTT) at day 29. Secondary endpoints included changes in fasting plasma glucose (FPG), insulin, HbA1c, lipids and body weight and adverse events. ANCOVA model was used for efficacy analysis.

RESULTS

The placebo-corrected least-squares mean differences (ΔLSM) in MMTT PPG AUC0-3 h (mmol/L) were -5.96 and -5.6 (both p = 0.03) in the MLR-1023 100-mg qd and 100-mg bid groups, respectively. The placebo-corrected ΔLSM in FPG (mmol/L) was -2.34 (p = 0.003) in the MLR-1023 100-mg qd group. Triglycerides improved with MLR-1023 (ΔLSM, -0.56 mmol/L, p = 0.07 and -0.59 mmol/L, p = 0.05) in the 200mgqd and 200 mg bid groups, respectively. Reductions in fasting insulin, HbA1c and body weight were not statistically significant. Most common adverse events with MLR-1023 treatment were headache (4.2%) and somnolence (2.5%).

CONCLUSIONS

MLR-1023 100-mg once-daily for 4 weeks was the most effective dose with significant reduction in PPG AUC following a MMTT. MLR-1023 was safe and well-tolerated in patients with type 2 diabetes. Clinical Trials Registration Number: NCT02317796.

Effects of Dapagliflozin on Endothelial Function, Renal Injury Markers, and Glycemic Control in Drug-Naïve Patients with Type 2 Diabetes Mellitus

BACKGROUND

The study aimed to evaluate the effects of dapagliflozin and metformin on vascular endothelial function and renal injury markers.

METHODS

This prospective, randomized, open-label, crossover study included drug-naïve patients with type 2 diabetes mellitus, who were randomized to receive 8 weeks of initial treatment using metformin or dapagliflozin and crossed over for another 8 weeks of treatment after a 1-week washout period. Systemic endothelial function was evaluated via the reactive hyperemic index (RHI).

RESULTS

The 22 participants included 10 males (45.5%) and had a median age of 58 years. The RHI values were not significantly changed during both 8-week treatment periods and there was no significant difference between the treatments. Relative to the metformin group, 8 weeks of dapagliflozin treatment produced significantly higher median N-acetyl-beta-D-glucosaminidase levels (10.0 ng/mL [interquartile range (IQR), 6.8 to 12.1 ng/mL] vs. 5.6 ng/mL [IQR, 3.8 to 8.0 ng/mL], P=0.013). Only the dapagliflozin group exhibited improved homeostatic model assessment of insulin resistance and body weight, while serum ketone and β-hydroxybutyrate levels increased.

CONCLUSION

Dapagliflozin treatment did not affect systemic endothelial function or renal injury markers except N-acetyl-beta-D-glucosaminidase.

Efficacy and Safety of Sodium-Glucose Cotransporter-2 Inhibitors in Korean Patients with Type 2 Diabetes Mellitus in Real-World Clinical Practice

BACKGROUND

This study aimed to evaluate the efficacy and safety of sodium-glucose cotransporter-2 (SGLT2) inhibitors in Korean patients who had inadequately controlled type 2 diabetes mellitus (T2DM) in real-world clinical practice.

METHODS

We included 410 patients who started SGLT2 inhibitors (empagliflozin or dapagliflozin) as add-on therapy or switch therapy between February 2015 and June 2017. The primary efficacy endpoint was a change in glycosylated hemoglobin (HbA1c) from baseline to week 12. The secondary endpoints were patients achieving HbA1c <7.0% and changes in the fasting plasma glucose (FPG), lipid profiles, body weight, and blood pressure (BP).

RESULTS

The mean HbA1c at baseline was 8.5% (8.6% in the add-on group and 8.4% in the switch group). At week 12, the mean adjusted HbA1c decreased by -0.68% in the overall patients (P<0.001), by -0.94% in the add-on group, and by -0.42% in the switch group. Significant reductions in FPG were also observed both in the add-on group and switch group (-30.3 and -19.8 mg/dL, respectively). Serum triglyceride (-16.5 mg/dL), body weight (-2.1 kg), systolic BP (-4.7 mm Hg), and diastolic BP (-1.3 mm Hg) were significantly improved in the overall patients. Approximately 18.3% of the patients achieved HbA1c <7.0% at week 12. A low incidence of hypoglycemia and genital tract infection was observed (6.3% and 2.2%, respectively).

CONCLUSION

SGLT2 inhibitors can be a suitable option as either add-on or switch therapy for Korean patients with inadequately controlled T2DM.

2019 Clinical Practice Guidelines for Type 2 Diabetes Mellitus in Korea

The Committee of Clinical Practice Guidelines of the Korean Diabetes Association revised and updated the 6th Clinical Practice Guidelines in 2019. Targets of glycemic, blood pressure, and lipid control in type 2 diabetes mellitus (T2DM) were updated. The obese and overweight population is increasing steadily in Korea, and half of the Koreans with diabetes are obese. Evidence-based recommendations for weight-loss therapy for obesity management as treatment for hyperglycemia in T2DM were provided. In addition, evidence from large clinical studies assessing cardiovascular outcomes following the use of sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide 1 receptor agonists in patients with T2DM were incorporated into the recommendations.

Taking metformin and cognitive function change in older patients with diabetes

AIM

We investigated the effects of metformin on cognitive function in a prospective cohort of older adults.

METHODS

Participants aged ≥60 years were selected, and their Korean version of the Consortium to Establish a Registry for Alzheimer's Diseases Assessment, including the Mini-Mental State Examination, and activities of daily living were evaluated prospectively. Rapid deterioration of cognitive function was defined as annual change of test scores in the lowest quartile.

RESULTS

A total of 732 participants (mean age 76.7 ± 6.6 years) were followed up for 2.9 years (interquartile range 1.0-5.7 years). A linear mixed model showed that diabetes was associated with significant deterioration of Verbal Delayed Free Recall and Recognition scores (P = 0.007 and 0.022, respectively). Among diabetes patients, metformin treatment was not associated with changes of any Korean version of the Consortium to Establish a Registry for Alzheimer's Diseases Assessment component or activities of daily living index. However, rapid deterioration of Mini-Mental State Examination and Verbal Immediate Recall scores was more frequently found in the metformin-taking group, even after adjustment for age, sex, education level, baseline cognitive function, baseline glycated hemoglobin levels, renal and liver function, body mass index, hypertension, dyslipidemia, antidiabetic agents other than metformin, and baseline brain imaging abnormality (odds ratio 4.47, 95% confidence interval 1.24-16.05 and odds ratio 7.37, 95% confidence interval 1.19-45.56).

CONCLUSIONS

Metformin treatment was not associated with changes of any of Korean version of the Consortium to Establish a Registry for Alzheimer's Diseases Assessment component scores or activities of daily living index. However, rapid deterioration of Mini-Mental State Examination and Verbal Immediate Recall scores was more frequently found in the metformin-treated group. Geriatr Gerontol Int 2019; 19: 755-761.

Effect of sodium-glucose cotransporter 2 inhibitor, empagliflozin, and α-glucosidase inhibitor, voglibose, on hepatic steatosis in an animal model of type 2 diabetes

OBJECTIVE

We investigated the effects of sodium-glucose cotransporter 2 inhibitor, empagliflozin, and α-glucosidase inhibitor, voglibose, on hepatic steatosis in an animal model of type 2 diabetes (T2DM).

METHODS

Empagliflozin (OLETF-EMPA) or voglibose (OLETF-VOG) was administered to Otsuka Long-Evans Tokushima fatty (OLETF) rats once daily for 12 weeks. Control Long-Evans Tokushima Otsuka (LETO) and OLETF (OLETF-C) rats received saline.

RESULTS

Blood glucose levels were significantly suppressed in OLETF-EMPA and OLETF-VOG compared with the OLETF-C group. The liver fat content was significantly higher in the OLETF-C group than in the OLETF-EMPA and OLETF-VOG. Hepatic gene expressions involved in gluconeogenesis (glucose 6-phosphatase [G6Pase], fructose-1,6-bisphosphatase [FBP1], and phosphoenolpyruvate carboxykinase [PEPCK]) and lipogenesis (acetyl-CoA carboxylase [ACC], fatty acid synthase [FAS], and sterol regulatory element-binding transcription factor 1c [SREBP-1c]) were significantly decreased in the OLETF-EMPA group compared with other OLETF groups (OLETF-C and OLETF-VOG). Sirtuin 1 (SIRT1) expression level and SIRT1 activity were markedly reduced in OLETF-C rats; however, its expression increased in the OLETF-EMPA and OLETF-VOG. AMP-activated protein kinase (AMPK) phosphorylation level was remarkably increased by empagliflozin treatment in OLETF rats compared with other OLETF groups. Long-term empagliflozin and voglibose treatment reduced hepatic steatosis with suppression of gluconeogenesis and lipogenesis pathway in OLETF rats.

CONCLUSION

We suggest that this metabolic improvement might be related to SIRT1 and AMPK pathway in T2DM. But empagliflozin is thought to have more advantage to prevent hepatic steatosis than voglibose in T2DM.

Non-fasting triglyceride levels in the Korean population with and without ischemic heart disease and cerebrovascular disease

BACKGROUND/AIMS

Associations between non-fasting triglyceride (TG) levels and a risk of ischemic heart disease (IHD) and cerebrovascular accident (CVA) have been suggested in Caucasians. We aimed to investigate whether non-fasting TG levels reflect the risk of IHD/CVA in Koreans.

METHODS

We conducted an analysis of patients aged ≥ 30 years from the nationwide survey database. Fasting TG was defined as a measurement taken ≥ 12 hours since the last meal. Non-fasting TG was categorized by fasting duration of 0 to 3, 4 to 7, and 8 to 11 hours.

RESULTS

In subjects without history of IHD/CVA, diabetes, or lipid-lowering medication, the TG level was significantly elevated for 7 hours in men compared to fasting TG levels (p = 0.011); the mean TG levels were 154.9 mg/dL (standard error [SE], 13.0), 177.0 mg/dL (SE, 12.1), 148.8 mg/dL (SE, 2.8), and 141.5 mg/dL (SE, 1.4) for 0 to 3, 4 to 7, 8 to 11, and ≥12 hours' fasting, respectively. In women, there was no difference in TG level according to fasting duration after adjustment for confounders. In men without diabetes, the TG level from 4 to 7 hours' fasting showed a significant difference between subjects with or without IHD/CVA even after adjustments for age, body mass index, lipid medication, exercise, and dietary factors (215.1 mg/dL vs. 177.3 mg/dL, p < 0.001).

CONCLUSION

In men, non-fasting TG levels from 4 to 7 hours' fasting were significantly associated with IHD/CVA, and were superior to fasting TG levels level in the significant association with the history of IHD or CVA.