How Can We Adopt the Glucose Tolerance Test to Facilitate Predicting Pregnancy Outcome in Gestational Diabetes Mellitus?

BACKGROUND

We investigated how 100-g oral glucose tolerance test (OGTT) results can be used to predict adverse pregnancy outcomes in gestational diabetes mellitus (GDM) patients.

METHODS

We analyzed 1,059 pregnant women who completed the 100-g OGTT between 24 and 28 weeks of gestation. We compared the risk of adverse pregnancy outcomes according to OGTT patterns by latent profile analysis (LPA), numbers to meet the OGTT criteria, and area under the curve (AUC) of the OGTT graph. Adverse pregnancy outcomes were defined as a composite of preterm birth, macrosomia, large for gestational age, low APGAR score at 1 minute, and pregnancy-induced hypertension.

RESULTS

Overall, 257 participants were diagnosed with GDM, with a median age of 34 years. An LPA led to three different clusters of OGTT patterns; however, there were no significant associations between the clusters and adverse pregnancy outcomes after adjusting for confounders. Notwithstanding, the risk of adverse pregnancy outcome increased with an increase in number to meet the OGTT criteria (P for trend=0.011); odds ratios in a full adjustment model were 1.27 (95% confidence interval [CI], 0.72 to 2.23), 2.16 (95% CI, 1.21 to 3.85), and 2.32 (95% CI, 0.66 to 8.15) in those meeting the 2, 3, and 4 criteria, respectively. The AUCs of the OGTT curves also distinguished the patients at risk of adverse pregnancy outcomes; the larger the AUC, the higher the risk (P for trend=0.007).

CONCLUSION

The total number of abnormal values and calculated AUCs for the 100-g OGTT may facilitate tailored management of patients with GDM by predicting adverse pregnancy outcomes.

Statin Therapy and the Risk of Osteoporotic Fractures in Patients with Metabolic Syndrome: a Nested Case-Control Study

OBJECTIVE

We aimed to investigate the association between statin use and the risk of major osteoporotic fractures in patients with metabolic syndrome (MetS).

METHODS

A nested case-control study was performed in patients with MetS (≥50 years) who had no history of osteoporotic fracture using the Korean National Health Insurance Service-Health Screening Cohort. This study included 17,041 patients diagnosed with new-onset osteoporotic fractures and controls matched in a 1:1 ratio by age, sex, body mass index, cohort entry date, and follow-up duration. Conditional logistic regression analysis was used to evaluate covariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

During a 4-year follow-up period, the risk of major osteoporotic fractures was significantly reduced by 9% (OR, 0.91; 95% CI, 0.85-0.97) in statin users compared with that in non-users. Among subtypes of major osteoporotic fracture, a risk reduction with statin therapy was significant for vertebral fracture (OR, 0.86; 95% CI, 0.79-0.94) but not for non-vertebral fracture (OR, 0.97; 95% CI, 0.88-1.06). Longer duration (OR, 0.97; 95% CI, 0.96-0.99, per 1-year increase) and higher cumulative dose (OR, 0.97; 95% CI, 0.95-0.99, per 365 defined daily doses) of statins were negatively associated with the risk of major osteoporotic fracture.

CONCLUSION

This study supports the hypothesis that statin therapy has a beneficial effect on major osteoporotic fractures, especially vertebral fractures, in patients with MetS.

Association Between Visit-to-Visit Fasting Plasma Glucose Variability and Osteoporotic Fractures in Nondiabetic Subjects

CONTEXT

Although long-term glucose variability has been reported to be a risk factor associated with osteoporosis, there have been no previous studies between the relationship of glucose variability and fractures in people without diabetes.

OBJECTIVE

We assessed visit-to-visit variations in fasting plasma glucose (FPG) as a prognostic factor in predicting osteoporotic fractures in individuals without diabetes.

METHODS

Using a nationwide cohort database, we examined the impact of FPG on the development of osteoporotic fractures in men and women (aged ≥50 years). The primary outcomes were the number of total fractures and vertebral fractures. FPG variability was measured using standard deviation (FPG-SD), coefficient of variation (FPG-CV), and variability independent of the mean (FPG-VIM).

RESULTS

Of the 92 929 participants, 5262 (5.7%) developed osteoporotic fractures during the mean follow-up of 8.4 years. Individuals in the highest quartile of FPG-SD showed an 11% and 16% increase in risk of total and vertebral fractures, respectively, compared with those in the lowest quartile after adjustment for mean FPG and other risk factors. Analyses using FPG-CV and FPG-VIM demonstrated similar results. Subgroup analyses and sensitivity analyses to explore potential heterogeneity showed consistent results.

CONCLUSION

FPG variability may be a novel risk factor for osteoporotic fractures independent of risk factors in the general population without diabetes.

Weight Gain Predicts Metabolic Syndrome among North Korean Refugees in South Korea

Previous cross-sectional studies showed that immigrants from low-income to high-income countries have higher risk of cardiovascular disease and type 2 diabetes mellitus. We investigated the association between weight gain during the resettlement in South Korea and risk of metabolic syndrome (MetS) among North Korean refugees (NKRs) in this cross-sectional study. In total, 932 NKRs aged 20-80 years in South Korea voluntarily underwent health examination from 2008 to 2017. We compared the risk of MetS and its components between the weight gain group (gained ≥5 kg) and the non-weight gain group (gained <5 kg, maintained or lost body weight) during resettlement in South Korea after defection from North Korea. Multiple logistic regression analysis predicted odds ratio of MetS on the basis of weight change, adjusting for covariates and current body mass index (BMI). We also evaluated the difference in body composition of NKRs between two groups. The prevalence of MetS in the weight gain group was 26%, compared to 10% in the non-weight gain group (p-value < 0.001). The weight gain group had a two-fold higher risk of MetS than the non-weight gain group after adjusting for current BMI (odds ratio 1.875, p-value = 0.045). The prevalence of central obesity, impaired fasting glucose, elevated blood pressure, and hypertriglyceridemia were higher in the weight gain group than the non-weight gain group (36% vs. 12%, p-value < 0.001; 32% vs. 19%, p-value < 0.001; 34 vs. 25%, p-value = 0.008; 19% vs. 13%, p-value = 0.025, respectively). The analysis of body composition showed that the percentage of body fat in the weight gain group was higher than in the non-weight gain group, indicating increased fat mass rather than muscle mass in the weight gain group as their body weight increased during resettlement (33.4 ± 6.53% vs. 28.88 ± 7.40%, p < 0.005). Excess weight gain after defection from North Korea increased the risk of MetS among NKRs in South Korea. It is necessary to monitor weight change among NKRs and their effect on their metabolic health in the long term.

Glycemic variability and the risk of nonalcoholic fatty liver disease : A nationwide population-based cohort study

AIM

Although few recent studies have reported the association between the glycemic variability and the development of type 2 diabetes mellitus and cardiovascular disease in individuals without diabetes mellitus, the impact of the long-term variability in fasting plasma glucose (FPG) levels on the incident nonalcoholic fatty liver disease (NAFLD) has not been evaluated.

METHODS

The study included 57,636 Korean men and women without NAFLD and diabetes mellitus from the Korean National Health Insurance System cohort. FPG variability was calculated using the coefficient of variation (FPG-CV), standard deviation (FPG-SD), variability independent of the mean (FPG-VIM), and average successive variability (FPG-ASV).

RESULTS

The cumulative incidence of NAFLD demonstrated progressively increasing trends according to the higher quartiles of FPG variability in Kaplan-Meier curves. A multivariable Cox proportional hazard analysis revealed that the hazard ratio for incident NAFLD was 1.15 (95% confidence interval, 1.06-1.24) in the highest quartile of FPG-CV compared with the lowest quartile of FPG-CV after adjusting for various confounding factors, including mean FPG levels. When using FPG-SD, FPG-VIM, and FPG-ASV, the results were similar. The 10-unit increase in FPG variability was associated with a 14% increased risk of NAFLD in the fully adjusted model. Moreover, this effect remained consistent in the subgroup and sensitivity analyses.

CONCLUSION

Increased long-term FPG variability is associated with the development of NAFLD, independent of confounding risk variables including mean FPG levels.

Detection of free-living amoebae in domestic cats with and without naturally-acquired keratitis

Pathogenic free-living amoebae, most notably Acanthamoeba spp., are important pathogens of the human cornea. The importance of infection with free-living amoebae in cats with keratitis is currently unclear. The aim of this study was to determine the frequency of amoeba detection in corneas of cats with naturally-acquired keratitis and in the ocular surface microflora of cats without ocular disease. Clinical ophthalmic and in vivo corneal confocal microscopic examinations were performed on 60 cats with keratitis. Corneal scrapings were analyzed by amoeba culture; cytological evaluation; and Acanthamoeba, Hartmannella, and Vahlkampfia PCR assays. Following ophthalmic examination, conjunctival specimens collected from 60 cats without clinically apparent ocular disease were analyzed similarly. In one cat with ulcerative keratitis, amoeba cysts and trophozoites were detected by in vivo corneal confocal microscopy; an Acanthamoeba sp. was isolated from corneal specimens and detected by Acanthamoeba PCR assay; and suppurative corneal inflammation was present cytologically. An Acanthamoeba sp. was isolated from conjunctival specimens from one cat without clinically apparent ocular disease, but with suppurative inflammation demonstrated cytologically. Both Acanthamoeba isolates belonged to the T4 genotype. Naegleria-like amoebae were isolated in samples from two cats with keratitis and seven cats without clinical ocular disease, but amoebae were not detected by the other assays in these samples. Amoeba detection by culture was significantly (P = 0.01) associated with cytologically diagnosed corneoconjunctival inflammation. This study identified naturally-acquired Acanthamoeba keratitis in cats. Detection of Naegleria-like amoebae in samples from cats with and without keratitis is of uncertain pathological significance.

Trends in Pediatric Thyroid Cancer Incidence, Treatment, and Clinical Course in Korea During 2004-2016: A Nationwide Population-Based Study

Background: The incidence of thyroid cancer has increased worldwide. We investigated nationwide trends in the incidence and treatment course of pediatric thyroid cancer in South Korea. Methods: Using the National Health Information Database, we analyzed 1580 patients (324 males) <20 years of age diagnosed with thyroid cancer during 2004-2016 in South Korea. The annual percentage change (APC) in the age-standardized incidence rate (ASR) was calculated by joinpoint regression analysis. The initial treatment modality was categorized as either surgery only or surgery with radioactive-iodine treatment (surgery+RAIT), and we defined new treatment events as reoperations or additional RAITs among 1464 patients followed up for ≥12 months. Results: During 2004-2016, the mean ASR per 100,000 person-years increased from 0.6 [confidence interval; CI 0.5-0.8] to 0.9 [CI 0.8-1.1], with a mean APC of 4.0% [CI 1.8-6.2]. The ASRs (APCs) among 0-9-, 10-14-, 15-17-, and 18-19-year olds were 0.07 (9.9% [CI 0.08-20.7]), 0.6 (4.6% [CI 0.2-9.2]), 2.2 (3.9 [CI 1.7-6.0]), and 4.2 (3.5% [CI 0.9-6.2]), respectively. The lobectomy and lymph-node-dissection rates increased (from 18.5% to 33.6%, p = 0.0014; and from 29.6% to 84.5%, p < 0.001; respectively), but the RAIT rate decreased (67.9-39.7%, p < 0.001) during the study period. During a median 6.3-year follow-up, two patients died. New treatment events occurred in 56 (10.7%) of patients in the initial surgery-only group (n = 523). In the initial surgery+RAIT group (n = 941), 316 patients received two or more RAITs within 2 years, and 80 (12.8%) of the remaining 625 patients underwent new treatment events. In the surgery+RAIT subgroup, the event-free survival rate was lower in 0-14-year olds than in 18-19-year olds (hazard ratio 2.5 [CI 1.4-4.4]). Conclusions: The pediatric thyroid cancer incidence increased from 2004 to 2012 in South Korea. The lobectomy and lymph-node-dissection rates increased, but the RAIT rate decreased. The higher risk for new treatment events in patients younger than 15 years requiring initial RAIT may be linked to advanced stage at diagnosis, and it needs to be further evaluated.

Weight-adjusted waist index reflects fat and muscle mass in the opposite direction in older adults

BACKGROUND

Age-related changes in body composition include decreased muscle mass and preserved or increased fat mass. There is no anthropometric index to assess both muscle and fat mass.

METHODS

Using a cross-sectional sample of 602 participants aged ≥65 years from the Ansan Geriatric study, we evaluated the association of weight-adjusted waist index (WWI) with muscle and fat mass and compared these with body mass index (BMI) and waist circumference (WC). WWI was calculated as WC (cm) divided by the square root of body weight (kg). Body composition was measured using bioelectrical impedance analysis, dual-energy X-ray absorptiometry and abdominal computed tomography.

RESULTS

WWI positively correlated with total abdominal fat area (TFA) (r = 0.421, P < 0.001), visceral fat area (VFA) (r = 0.264, P < 0.001), and percentage of total tissue fat (r = 0.465, P < 0.001), but negatively correlated with appendicular skeletal muscle mass (ASM) (r = -0.511, P < 0.001) and ASM/height2 (r = -0.324, P < 0.001). Mean ASM was highest in the first quartile of WWI (17.85 kg/m2) and showed a decreasing trend, with the lowest value in the fourth WWI quartile (13.21 kg/m2, P for trend <0.001). In contrast, mean TFA was lowest in the first quartile and highest in the fourth WWI quartile (P for trend <0.001). The probability of combined low muscle mass and high fat mass was >3× higher in the fourth WWI quartile than in the lowest quartile (odds ratio 3.22, 95% confidence interval 1.32-7.83).

CONCLUSIONS

WWI is an anthropometric index positively associated with fat mass and negatively associated with muscle mass in older adults.

Effect of Statin Use on the Risk of Osteoporotic Fracture in Patients With Metabolic Syndrome: A Nested Case-Control Study

Statins may have advantageous pleiotropic effects on bone metabolism, however, the clinical evidence about the association is still unclear. Although many studies have already evaluated this association, they have performed mostly in a general population with limitation of between-study heterogeneity. Statin may not be equally effective for bone metabolism to every patient, but it can give some benefits for some patients especially with metabolic syndrome (MetS). However, no recent study assessing this relationship, to best our knowledge, has evaluated specifically on patients with MetS. It is also unclear whether the association between statin and osteoporotic fracture differ by statin intensity, dose (cumulative defined daily dose), and duration. This study aimed to investigate the association of statin use with the risk of major osteoporotic fracture in MetS patients from a population-based cohort (NHIS-HEALS, 2002–2015). A nested case-control study was performed in patients with MetS (≥50 years) who had no history of previous osteoporotic fracture. This study included 17,041 cases diagnosed as new-onset osteoporotic fractures and controls matched in a 1:1 ratio by age, sex, body mass index, cohort entry date, and follow-up duration. Conditional logistic regression analysis was used to evaluate covariate-adjusted odds ratio (OR) and 95% confidence interval (CI). During the 4-year follow up period, statin users had a significantly lower risk of major osteoporotic fractures by 9% (OR, 0.91; 95% CI, 0.85 to 0.97) compared with non-users. Among subtypes of major osteoporotic fracture, a risk reduction of vertebral fracture was significant (OR, 0.86; 95% CI, 0.79 to 0.94), but not non-vertebral fracture (OR, 0.97; 95% CI, 0.88 to 1.06) with statin use. Longer duration (OR, 0.97 per 1 year) and cumulative dose (OR, 0.97 per 365 defined daily dose) of statin was negatively associated with the risk of major osteoporotic fracture. There was no difference in risk of major osteoporotic fractures among groups according to statin intensity. In conclusion, this study supports the hypothesis that statin treatment has a beneficial effect on major osteoporotic fracture, especially for vertebral fracture, in patients with MetS with a possibly dose-effect relationship.

Use of Renin-Angiotensin-Aldosterone System Inhibitors and Severe COVID-19 Outcomes in Patients with Hypertension: A Nationwide Cohort Study

BACKGROUND

Angiotensin-converting enzyme 2 facilitates the entry of severe acute respiratory syndrome coronavirus 2 into the human body. We investigated the association of renin-angiotensin-aldosterone system (RAAS) inhibitor use with severe coronavirus disease 2019 (COVID-19) outcomes in hypertensive patients.

METHODS

We identified hypertensive patients with confirmed COVID-19 from the Korean Health Insurance Review and Assessment Service from inception to May 15, 2020. The primary outcome was the composite of intensive care unit (ICU) admission, invasive mechanical ventilation (IMV), continuous renal replacement therapy (CRRT), extracorporeal membrane oxygenation (ECMO), and death from COVID-19. The individual components were evaluated as secondary outcomes.

RESULTS

Of 1,374 hypertensive patients with COVID-19, 1,076 (78.3%) and 298 (21.7%) were users and never-users of RAAS inhibitors, respectively. The RAAS inhibitor users were not associated with the risk of the primary outcome (adjusted odds ratio [aOR], 0.72; 95% confidence interval [CI], 0.46 to 1.10). The risk of ICU admission was significantly lower in the users than the never-users (aOR, 0.44; 95% CI, 0.24 to 0.84). The RAAS inhibitors were beneficial only in ICU admissions that did not require IMV (aOR, 0.28; 95% CI, 0.14 to 0.58). The risk of death from COVID-19 was comparable between the groups (aOR, 1.09; 95% CI, 0.64 to 1.85). We could not evaluate the risks of CRRT and ECMO owing to the small number of events.

CONCLUSION

RAAS inhibitor use was not associated with the composite of severe outcomes in the hypertensive patients with COVID-19 but significantly lowered the risk of ICU admission, particularly in patients who did not require IMV.

Time to Reach Target Glycosylated Hemoglobin Is Associated with Long-Term Durable Glycemic Control and Risk of Diabetic Complications in Patients with Newly Diagnosed Type 2 Diabetes Mellitus: A 6-Year Observational Study

BACKGROUND

To evaluate the association of time to reach the target glycosylated hemoglobin (HbA1c) level with long-term durable glycemic control and risk of diabetic complications in patients with newly diagnosed type 2 diabetes mellitus (T2DM).

METHODS

In a longitudinal observational cohort, 194 patients with T2DM newly diagnosed between January 2011 and March 2013 were followed up over 6 years. Patients were classified according to the time needed to reach the target HbA1c (<7.0%): <3, 3 to 6 (early achievement group), and ≥6 months (late achievement group). Risks of microvascular complications including diabetic retinopathy, nephropathy, and neuropathy as well as macrovascular events including ischemic heart disease, ischemic stroke, and peripheral arterial disease were assessed by multivariable Cox proportional hazards analysis.

RESULTS

During a median follow-up of 6.53 years, 66 microvascular and 14 macrovascular events occurred. Maintenance of durable glycemic control over 6 years was more likely in the early achievement groups than in the late achievement group (34.5%, 30.0%, and 16.1% in <3, 3 to 6, and ≥6 months, respectively, P=0.039). Early target HbA1c achievement was associated with lower risk of composite diabetic complications (adjusted hazard ratio [HR, 0.47; 95% confidence interval [CI], 0.26 to 0.86 in <3 months group) (adjusted HR, 0.50; 95% CI, 0.23 to 1.10 in 3 to 6 months group, in reference to ≥6 months group). Similar trends were maintained for risks of microvascular and macrovascular complications, although statistical significance was not reached for macrovascular complications.

CONCLUSION

Early target HbA1c achievement was associated with long-term durable glycemic control and reduced risk of diabetic complications in newly diagnosed T2DM.

Comparative Renal Effects of Dipeptidyl Peptidase-4 Inhibitors and Sodium-Glucose Cotransporter 2 Inhibitors on Individual Outcomes in Patients with Type 2 Diabetes: A Systematic Review and Network Meta-Analysis

BACKGROUND

To compare the renal effects of dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium-glucose cotransporter 2 (SGLT2) inhibitors on individual outcomes in patients with type 2 diabetes.

METHODS

We searched electronic databases (MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials) from inception to June 2019 to identity eligible randomized controlled trials of DPP-4 inhibitors or SGLT2 inhibitors that reported at least one kidney outcome in patients with type 2 diabetes. Outcomes of interest were microalbuminuria, macroalbuminuria, worsening nephropathy, and end-stage kidney disease (ESKD). We performed an arm-based network meta-analysis using Bayesian methods and calculated absolute risks and rank probabilities of each treatment for the outcomes.

RESULTS

Seventeen studies with 87,263 patients were included. SGLT2 inhibitors significantly lowered the risks of individual kidney outcomes, including microalbuminuria (odds ratio [OR], 0.64; 95% credible interval [CrI], 0.41 to 0.93), macroalbuminuria (OR, 0.48; 95% CrI, 0.24 to 0.72), worsening nephropathy (OR, 0.65; 95% CrI, 0.44 to 0.91), and ESKD (OR, 0.65; 95% CrI, 0.46 to 0.98) as compared with placebo. However, DPP-4 inhibitors did not lower the risks. SGLT2 inhibitors were considerably associated with higher absolute risk reductions in all kidney outcomes than DPP-4 inhibitors, although the benefits were statistically insignificant. The rank probabilities showed that SGLT2 inhibitors were better treatments for lowering the risk of albuminuria and ESKD than placebo or DPP-4 inhibitors.

CONCLUSION

SGLT2 inhibitors were superior to DPP-4 inhibitors in reducing the risk of albuminuria and ESKD in patients with type 2 diabetes.

Age- and Sex-Related Differential Associations between Body Composition and Diabetes Mellitus

BACKGROUND

The age- and sex-related differences on the impacts of body composition on diabetes mellitus (DM) remain uncertain.

METHODS

The fourth and fifth Korea National Health and Nutrition Examination Survey included 15,586 subjects over 30 years of age who completed dual-energy X-ray absorptiometry. We conducted a cross-sectional study to investigate whether muscle mass index (MMI), defined as appendicular skeletal muscle divided by body mass index (BMI), and fat mass index (FMI), defined as trunk fat mass divided by BMI, were differently associated with DM according to age and sex.

RESULTS

In multivariate logistic regression, the risk for DM significantly increased across quartiles of FMI in men aged ≥70. Meanwhile, MMI showed a protective association with DM in men of the same age. The odds ratios (ORs) for the highest quartile versus the lowest quartile of FMI and MMI were 3.116 (95% confidence interval [CI], 1.405 to 6.914) and 0.295 (95% CI, 0.157 to 0.554), respectively. In women, the ORs of DM was significantly different across FMI quartiles in those over age 50. The highest quartile of FMI exhibited increased ORs of DM in subjects aged 50 to 69 (OR, 1.891; 95% CI, 1.229 to 2.908) and ≥70 (OR, 2.275; 95% CI, 1.103 to 4.69) compared to lowest quartile. However, MMI was not significantly associated with DM in women of all age groups.

CONCLUSION

Both FMI and MMI were independent risk factors for DM in men aged 70 years or more. In women over 50 years, FMI was independently associated with DM. There was no significant association between MMI and DM in women.

Consensus Recommendations by the Asian Pacific Society of Cardiology: Optimising Cardiovascular Outcomes in Patients with Type 2 Diabetes

The Asian Pacific Society of Cardiology convened a consensus statement panel for optimising cardiovascular (CV) outcomes in type 2 diabetes, and reviewed the current literature. Relevant articles were appraised using the Grading of Recommendations, Assessment, Development and Evaluation system, and consensus statements were developed in two meetings and were confirmed through online voting. The consensus statements indicated that lifestyle interventions must be emphasised for patients with prediabetes, and optimal glucose control should be encouraged when possible. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are recommended for patients with chronic kidney disease with adequate renal function, and for patients with heart failure with reduced ejection fraction. In addition to SGLT2i, glucagon-like peptide-1 receptor agonists are recommended for patients at high risk of CV events. A blood pressure target below 140/90 mmHg is generally recommended for patients with type 2 diabetes. Antiplatelet therapy is recommended for secondary prevention in patients with atherosclerotic CV disease.

Association of the triglyceride and glucose index with low muscle mass: KNHANES 2008-2011

The triglyceride-glucose (TyG) index is a simple surrogate marker of insulin resistance. We evaluated the association of the TyG index with low muscle mass using a nationwide population-based representative data. This is a cross-sectional study that included 9477 participants aged ≥ 40 years from the Korea National Health and Nutrition Examination Survey between 2008 and 2011. The TyG index was calculated as ln[triglyceride (mg/dL) × fasting plasma glucose (mg/dL)/2]. Dual-energy X-ray absorptiometry was used to measure appendicular lean mass (ALM). Low muscle mass was defined an ALM/weight of 2 standard deviations (SD) below of young participants. The overall prevalence of low muscle mass was 4.7%. The prevalence of low muscle mass increased linearly with the quartiles of the TyG index, 2.5%, 4.2%, 5.6%, and 6.7% in Q1–Q4, respectively. The TyG index was negatively associated with ALM/weight both in men (r = − 0.302) and women (r = − 0.230). The odds ratio (OR) for low muscle mass was 2.08 in the highest quartile compared to the lowest quartile. High TyG index was associated with an increased risk of low muscle mass (OR for 1SD increase: 1.13). Increased TyG index was associated with the risk of low muscle mass independent of confounding factors.

Long Working Hours and Risk of Nonalcoholic Fatty Liver Disease: Korea National Health and Nutrition Examination Survey VII

BACKGROUND

The global incidence of NAFLD is rising sharply due to various risk factors. As previous studies reported adverse health impact of long working hours on metabolic diseases, such as diabetes mellitus and obesity, it is plausible that NAFLD is also associated with working excessive hours. However, data regarding this issue is limited.

METHODS

In this cross-sectional study based on Korea National Health and Nutrition Examination Survey VII, 5,661 working adults without previous liver disease or heavy alcohol drinking habits were included. The subjects were categorized into three groups according to working hours: 36-42, 43-52, and 53-83 hours/week. NAFLD was defined using the hepatic steatosis index (HSI), which is a validated prediction model for determining NAFLD.

RESULTS

The prevalence of NAFLD (HSI ≥36) increased with longer working hours: 23.0%, 25.6%, and 30.6% in the 36-42, 43-52, and 53-83 hours/week group, respectively (p <0.001). Subjects who worked 53-83 hours/week had higher odds for NAFLD than those who worked the standard 36-42 hours/week (OR 1.23, 95% CI 1.02-1.50, p = 0.033) after adjusting for age, sex, body mass index, smoking, alcohol, exercise, diabetes mellitus, hypertension, serum triglyceride, and total cholesterol. This association was consistent across subgroups according to working schedule (daytime vs. shift workers) or occupation type (office vs. manual workers). In particular, the relationship between long working hours and NAFLD was pronounced in workers aged <60 years and in female workers.

CONCLUSIONS

Long working hours was significantly associated with NAFLD. Further prospective studies are required to validate this finding with causal relationship.

Early combination versus initial metformin monotherapy in the management of newly diagnosed type 2 diabetes: An East Asian perspective

Type 2 diabetes (T2D) in the East Asian population is characterized by phenotypes such as low body mass index, an index of β-cell dysfunction, and higher percentage of body fat, an index of insulin resistance. These phenotypes/pathologies may predispose people to early onset of diabetes with increased risk of stroke and renal disease. Less than 50% of patients with T2D in East Asia achieve glycaemic targets recommended by national or regional guidelines, which may be attributable to knowledge and/or implementation gaps. Herein, we review the latest evidence with special reference to East Asian patients with T2D and present arguments for the need to use early combination therapy to intensify glycaemic control. This strategy is supported by the 5-year worldwide VERIFY study, which reported better glycaemic durability in newly diagnosed patients with T2D with a mean HbA1c of 6.9% treated with early combination therapy of vildagliptin plus metformin versus those treated with initial metformin monotherapy followed by addition of vildagliptin only with worsening glycaemic control. This paradigm shift of early intensified treatment is now recommended by the American Diabetes Association and the European Association for the Study of Diabetes. In order to translate these evidence to practice, increased awareness and strengthening of the healthcare system are needed to diagnose and manage patients with T2D early for combination therapy.

Effect of Metabolic Health and Obesity Phenotype on the Risk of Pancreatic Cancer: A Nationwide Population-Based Cohort Study

BACKGROUND

Recently, a few studies have reported different results regarding the relationship between metabolic health and obesity phenotype and several cancers. We examined the effects of metabolic health and obesity phenotype on pancreatic cancer using a nationwide population-based cohort database.

METHODS

Using the Korean National Health Insurance Service-Health Screening Cohort, we enrolled 347,434 Korean adults who underwent a health examination between 2009 and 2010 and were followed until 2015. This population was divided into four groups based on metabolically healthy status and body mass index (BMI): metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO).

RESULTS

Over a median follow-up of 6.1 (5.5-6.5) years, 886 individuals were diagnosed with pancreatic cancer. The adjusted HRs for incident pancreatic cancer were 1.52 [95% confidence interval (CI) 1.27-1.81] and 1.34 (95% CI, 1.12-1.61) for the MUNW and MUO phenotypes (compared with the MHNW phenotype) after adjusting for various confounding factors. However, compared with the MHNW phenotype, the MHO phenotype did not show an elevated risk of pancreatic cancer. Moreover, the HR for pancreatic cancer gradually increased with an increase in number of metabolically unhealthy components, even after adjusting for BMI (P _trend < 0.001).

CONCLUSIONS

Regardless of BMI, metabolically unhealthy phenotype demonstrated significantly increased risk of pancreatic cancer, whereas obese individuals with metabolically healthy phenotype did not.

IMPACT

These findings suggest that metabolically unhealthy phenotype might represent a potential risk factor for pancreatic cancer occurrence independent of obesity.

Trends in the Diagnosis and Treatment of Patients with Medullary Thyroid Carcinoma in Korea

BACKGROUND

Thyroid cancer is becoming increasingly common worldwide, but little is known about the epidemiology of medullary thyroid carcinoma (MTC). This study investigated the current status of the incidence and treatment of MTC using Korean National Health Insurance Service (NHIS) data for the entire Korean population from 2004 to 2016.

METHODS

This study included 1,790 MTC patients identified from the NHIS database.

RESULTS

The age-standardized incidence rate showed a slightly decreasing or stationary trend during the period, from 0.25 per 100,000 persons in 2004 to 0.19 in 2016. The average proportion of MTC among all thyroid cancers was 0.5%. For initial surgical treatment, 65.4% of patients underwent total thyroidectomy. After surgery, external-beam radiation therapy (EBRT) was performed in 10% of patients, a proportion that increased from 6.7% in 2004 to 11.0% in 2016. Reoperations were performed in 2.7% of patients (n=49) at a median of 1.9 years of follow-up (interquartile range, 1.2 to 3.4). Since November 2015, 25 (1.4%) patients with MTC were prescribed vandetanib by December 2016.

CONCLUSION

The incidence of MTC decreased slightly with time, and the proportion of patients who underwent total thyroidectomy was about 65%. EBRT, reoperation, and tyrosine kinase inhibitor therapy are additional treatments after initial surgery for advanced MTC in Korea.

Association of early-onset diabetes, prediabetes and early glycaemic recovery with the risk of all-cause and cardiovascular mortality

AIMS/HYPOTHESIS

The increasing incidence of diabetes among young adults is a disease burden; however, the effects of early-onset diabetes, prediabetes and glycaemic recovery on CVD or mortality remain unclear. We aimed to investigate the association of these factors with 10 year all-cause mortality, CVD mortality and CVD incidence in Korean young adults.

METHODS

This large and longitudinal cohort study included data from the Korean National Health Insurance Service-National Health Information Database; 2,502,375 young adults aged 20-39 years without diabetes mellitus and CVD at baseline were included. Glycaemic status was measured twice, first in 2002-2003 and second in 2004-2005. Changes in fasting glucose levels were evaluated according to fasting glucose status: normal fasting glucose (NFG; <5.5 mmol/l), impaired fasting glucose (IFG; 5.5-6.9 mmol/l), and diabetic fasting glucose (DFG; ≥7.0 mmol/l). Primary outcomes were all-cause and CVD mortality risk. The secondary outcome was incidence of CVD, including acute myocardial infarction and stroke. All outcomes arose from the 10 year follow-up period 1 Jan 2006 to 31 December 2015.

RESULTS

Individuals with NFG at baseline, who were subsequently newly diagnosed with diabetes and prediabetes (IFG), had increased all-cause mortality (HR [95% CI] 1.60 [1.44, 1.78] and 1.13 [1.09, 1.18], respectively) and CVD incidence (1.13 [1.05, 1.23] and 1.04 [1.01, 1.07], respectively). In those with DFG at baseline, early recovery to NFG and IFG was associated with decreased all-cause mortality (0.57 [0.46, 0.70] and 0.65 [0.53, 0.81], respectively) and CVD incidence (0.70 [0.60, 0.81] and 0.78 [0.66, 0.91], respectively). Among patients with IFG at baseline, early recovery to NFG was associated with decreased CVD mortality (0.74 [0.59, 0.93]).

CONCLUSIONS/INTERPRETATION

Early-onset diabetes or prediabetes increased CVD risks and all-cause mortality after the 10 year follow-up. Furthermore, recovery of hyperglycaemia could reduce the subsequent 10 year risk for CVD incidence and all-cause mortality. Graphical abstract.

Effects of radioactive iodine treatment on cardiovascular disease in thyroid cancer patients: a nationwide cohort study

Background

Radioactive iodine (RAI) treatment is a standard treatment in differentiated thyroid cancer (TC). However, its adverse effects on cardiovascular diseases (CVDs) have not been clearly elucidated.

Methods

In this retrospective cohort study based on the Korean National Health Insurance Service-National Health Screening Cohort (2002–2015), we analyzed 4,845 patients with TC with a median follow-up of 66 months. We evaluated and compared the risk of CVD between patients treated with and without RAI therapy. The primary CVD outcome was defined as a composite of ischemic stroke (IS), ischemic heart disease (IHD), hemorrhagic stroke (HS), or heart failure (HF).

Results

Overall, 2,533 patients (52.3%) received RAI treatment with a median cumulative dosage of 103 mCi [interquartile range (IQR), 40–162 mCi]. The incidence of the primary CVD outcome in patients who did not receive RAI therapy and those who did was 17.32 [95% confidence interval (CI), 15.07–19.90] and 13.96 (95% CI, 12.17–16.01) per 1,000 person-years, respectively, indicating an adjusted hazard ratio (HR) of 0.87 (95% CI, 0.71–1.07) after multivariate adjustments for variable confounding factors. The risks of IS (HR, 0.83; 95% CI, 0.51–1.34), IHD (HR, 0.90; 95% CI, 0.71–1.13), HS (HR 1.01; 95% CI, 0.49–2.09), and HF (HR 0.89; 95% CI, 0.49–1.63) were comparable between the patients who received RAI therapy and those who did not. There was no cumulative dose-dependent risk for CVD in TC patients who received RAI treatment.

Conclusions

RAI treatment is a prevalent and crucial treatment for TC, and has been used in more than half of TC patients in Korea from 2004 to 2015. This study found no significant between-group difference for the CVD risk in patients with TC who received RAI treatment and those who did not, giving further evidence to allay concerns related to the adverse effects of RAI.

Efficacy and safety of lobeglitazone versus sitagliptin as an add-on to metformin in patients with type 2 diabetes with two or more components of metabolic syndrome over 24 weeks

We aimed to evaluate the efficacy and safety profile of lobeglitazone compared with sitagliptin as an add-on to metformin in patients with type 2 diabetes as well as other components of metabolic syndrome. Patients inadequately controlled by metformin were randomly assigned to lobeglitazone (0.5 mg, n = 121) or sitagliptin (100 mg, n = 126) for 24 weeks. The mean changes in HbA1c of the lobeglitazone and sitagliptin groups were -0.79% and -0.86%, respectively; the between-group difference was 0.08% (95% confidence interval, -0.14% to 0.30%), showing non-inferiority. The proportion of patients having two or more factors of other metabolic syndrome components decreased to a greater extent in the lobeglitazone group than in the sitagliptin group (-11.9% vs. -4.8%; P < .0174). Favourable changes in the lipid metabolism were also observed with lobeglitazone, which had a similar safety profile to sitagliptin. Lobeglitazone was comparable with sitagliptin as an add-on to metformin in terms of efficacy and safety.

Glucose variability and the risks of stroke, myocardial infarction, and all-cause mortality in individuals with diabetes: retrospective cohort study

BACKGROUND

Previous research regarding long-term glucose variability over several years which is an emerging indicator of glycemic control in diabetes showed several limitations. We investigated whether variability in long-term fasting plasma glucose (FG) can predict the development of stroke, myocardial infarction (MI), and all-cause mortality in patients with diabetes.

METHODS

This is a retrospective cohort study using the data provided by the Korean National Health Insurance Corporation. A total of 624,237 Koreans ≥ 20 years old with diabetes who had undergone health examinations at least twice from 2005 to 2008 and simultaneously more than once from 2009 to 2010 (baseline) without previous histories of stroke or MI. As a parameter of variability of FG, variability independent of mean (VIM) was calculated using FG levels measured at least three times during the 5 years until the baseline. Study endpoints were incident stroke, MI, and all-cause mortality through December 31, 2017.

RESULTS

During follow-up, 25,038 cases of stroke, 15,832 cases of MI, and 44,716 deaths were identified. As the quartile of FG VIM increased, the risk of clinical outcomes serially increased after adjustment for confounding factors including duration and medications of diabetes and the mean FG. Adjusted hazard ratios (95% confidence intervals) of FG VIM quartile 4 compared with quartile 1 were 1.20 (1.16-1.24), 1.20 (1.15-1.25), and 1.32 (1.29-1.36) for stroke, MI and all-cause mortality, respectively. The impact of FG variability was higher in the elderly and those with a longer duration of diabetes and lower FG levels.

CONCLUSIONS

In diabetes, long-term glucose variability showed a dose-response relationship with the risk of stroke, MI, and all-cause mortality in this nationwide observational study.

Prognostic value of long-term gamma-glutamyl transferase variability in individuals with diabetes: a nationwide population-based study

We examined whether long-term gamma-glutamyl transferase (GGT) variability can predict cardiovascular disease (CVD) and mortality in individuals with diabetes. We included 698,937 Koreans diabetes patients older than 40 years without histories of CVD, chronic liver disease, or heavy alcoholics who received health exams supported by the Korean government more than once in 2009-2012 (baseline). We used Cox proportional analyses to estimate the risk of stroke, myocardial infarction (MI), and all-cause mortality until December 31, 2016, according to the quartiles of the average successive variability (ASV) of GGT measured during the five years before the baseline. A total 26,119, 15,103, and 39,982 cases of stroke, MI, and death, respectively, were found. GGT ASV quartile 4 had a significantly higher risk of stroke and all-cause mortality than quartile 1, with adjustment for risk factors, such as baseline glucose and GGT level, and comorbidities. Hazard ratios (95% confidence intervals) for GGT ASV quartile 4 were 1.06 (1.03-1.10) and 1.23 (1.20-1.27) for stroke and mortality, respectively. This significant association was shown consistently across the baseline GGT quartiles. GGT variability was related to the risk of stroke and all-cause mortality. The effect was most pronounced in all-cause mortality, irrespective of baseline GGT level.