Background: The severity of coronavirus disease 2019 (COVID-19) among patients with long-term glucocorticoid treatment (LTGT) has not been established. We aimed to evaluate the association between LTGT and COVID-19 prognosis. Methods: A Korean nationwide cohort database of COVID-19 patients between January 2019 and September 2021 was used. LTGT was defined as exposure to at least 150 mg of prednisolone (≥5 mg/day and ≥30 days) or equivalent glucocorticoids 180 days before COVID-19 infection. The outcome measurements were mortality, hospitalization, intensive care unit (ICU) admission, length of stay, and mechanical ventilation. Results: Among confirmed patients with COVID-19, the LTGT group (n=12,794) was older and had a higher proportion of comorbidities than the control (n=359,013). The LTGT group showed higher in-hospital, 30-day, and 90-day mortality rates than the control (14.0% vs. 2.3%, 5.9% vs. 1.1%, and 9.9% vs. 1.8%, respectively; all P<0.001). Except for the hospitalization rate, the length of stay, ICU admission, and mechanical ventilation proportions were significantly higher in the LTGT group than in the control (all P<0.001). Overall mortality was higher in the LTGT group than in the control group, and the significance remained in the fully adjusted model (odds ratio [OR], 5.75; 95% confidence interval [CI], 5.31 to 6.23) (adjusted OR, 1.82; 95% CI, 1.67 to 2.00). The LTGT group showed a higher mortality rate than the control within the same comorbidity score category. Conclusion Long-term exposure to glucocorticoids increased the mortality and severity of COVID-19. Prevention and early proactive measures are inevitable in the high-risk LTGT group with many comorbidities.

Background: The effects of dipeptidyl peptidase 4 (DPP-4) inhibitors over the course of long-term treatment remain unclear, and concerns have been raised regarding the role of DPP-4 inhibitors in carcinogenesis in the pancreas. Earlier studies of pancreatic adverse events have reported conflicting results. Methods: This study analyzed Korean National Health Insurance Service data from January 2009 to December 2012. Patients who had type 2 diabetes mellitus and took two or more oral glucose-lowering drugs (GLDs) were included. Patients prescribed DPP-4 inhibitors (n=51,482) or other GLDs (n=51,482) were matched at a 1:1 ratio using propensity score matching. The risk of pancreatic cancer was calculated using Kaplan-Meier curves and Cox proportional-hazards regression analysis. Results: During a median follow-up period of 7.95 years, 1,051 new cases of pancreatic cancer were identified. The adjusted hazard ratio (HR) for DPP-4 inhibitor use was 0.99 (95% confidence interval [CI], 0.88 to 1.12) compared with the other GLD group. In an analysis limited to cases diagnosed with pancreatic cancer during hospitalization, the adjusted HR for the use of DPP-4 inhibitors was 1.00 (95% CI, 0.86 to 1.17) compared with patients who took other GLDs. Using the other GLD group as the reference group, no trend was observed for elevated pancreatic cancer risk with increased DPP-4 inhibitor exposure. Conclusion In this population-based cohort study, DPP-4 inhibitor use over the course of relatively long-term follow-up showed no significant association with an elevated risk of pancreatic cancer.

Background: This study evaluated the efficacy and safety of add-on gemigliptin in patients with type 2 diabetes mellitus (T2DM) who had inadequate glycemic control with metformin and dapagliflozin. Methods: In this randomized, placebo-controlled, parallel-group, double-blind, phase III study, 315 patients were randomized to receive either gemigliptin 50 mg (n=159) or placebo (n=156) with metformin and dapagliflozin for 24 weeks. After the 24-week treatment, patients who received the placebo were switched to gemigliptin, and all patients were treated with gemigliptin for an additional 28 weeks. Results: The baseline characteristics were similar between the two groups, except for body mass index. At week 24, the least squares mean difference (standard error) in hemoglobin A1c (HbA1c) changes was –0.66% (0.07) with a 95% confidence interval of –0.80% to –0.52%, demonstrating superior HbA1c reduction in the gemigliptin group. After week 24, the HbA1c level significantly decreased in the placebo group as gemigliptin was administered, whereas the efficacy of HbA1c reduction was maintained up to week 52 in the gemigliptin group. The safety profiles were similar: the incidence rates of treatment-emergent adverse events up to week 24 were 27.67% and 29.22% in the gemigliptin and placebo groups, respectively. The safety profiles after week 24 were similar to those up to week 24 in both groups, and no new safety findings, including hypoglycemia, were noted. Conclusion Add-on gemigliptin was well tolerated, providing comparable safety profiles and superior efficacy in glycemic control over placebo for long-term use in patients with T2DM who had poor glycemic control with metformin and dapagliflozin.

Background: This study investigated the risk of cause-specific mortality according to glucose tolerance status in elderly South Koreans. Methods: A total of 1,292,264 individuals aged ≥65 years who received health examinations in 2009 were identified from the National Health Information Database. Participants were classified as normal glucose tolerance, impaired fasting glucose, newly-diagnosed diabetes, early diabetes (oral hypoglycemic agents ≤2), or advanced diabetes (oral hypoglycemic agents ≥3 or insulin). The risk of system-specific and disease-specific deaths was estimated using multivariate Cox proportional hazards analysis. Results: During a median follow-up of 8.41 years, 257,356 deaths were recorded. Diabetes was associated with significantly higher risk of all-cause mortality (hazard ratio [HR], 1.58; 95% confidence interval [CI], 1.57 to 1.60); death due to circulatory (HR, 1.49; 95% CI, 1.46 to 1.52), respiratory (HR, 1.51; 95% CI, 1.47 to 1.55), and genitourinary systems (HR, 2.22; 95% CI, 2.10 to 2.35); and neoplasms (HR, 1.30; 95% CI, 1.28 to 1.32). Diabetes was also associated with a significantly higher risk of death due to ischemic heart disease (HR, 1.70; 95% CI, 1.63 to 1.76), cerebrovascular disease (HR, 1.46; 95% CI, 1.41 to 1.50), pneumonia (HR, 1.69; 95% CI, 1.63 to 1.76), and acute or chronic kidney disease (HR, 2.23; 95% CI, 2.09 to 2.38). There was a stepwise increase in the risk of death across the glucose spectrum (P for trend <0.0001). Stroke, heart failure, or chronic kidney disease increased the risk of all-cause mortality at every stage of glucose intolerance. Conclusion A dose-dependent association between the risk of mortality from various causes and severity of glucose tolerance was noted in the elderly population.

Objective: The consequences of blood lipid abnormalities for cardiovascular disease risk in young adults is unclear. Optimal lipid levels may also vary depending on whether a statin drug is taken. It aimed to determine whether the optimal lipid levels in young adults differ depending on statin use. Methods: Using a nationally representative database from the Korean National Health Insurance System, 6,350,400 participants aged 20–39 years who underwent a health examination between 2009–2012 were followed through to 2018. The primary outcome was incident myocardial infarction (MI). We assessed the associations between prespecified lipid levels and MI risk according to statin use. Results: Among participants not taking statins, low-density lipoprotein cholesterol (LDL-C) levels ≥120 mg/dL were significantly associated with MI risk (hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.27–1.40) compared with statin nonusers with LDL-C <80 mg/dL. Statin users with LDL-C categories <80, 80–100, 100–120, and ≥120 mg/dL all had significantly higher MI risk compared with statin nonusers with LDL-C <80 mg/dL; these HRs (95% CIs) were 1.66 (1.39–1.99), 1.68 (1.36–2.09), 1.63 (1.31–2.02), and 2.32 (2.07–2.60), respectively. Conclusion Young adults taking statins have an increased MI risk compared with statin nonusers, even when they have similar LDL-C levels. Specific lipid targets may need to differ depending on statin use.

We assessed the glycaemic durability with early combination (EC; vildagliptin+metformin [MET], n=22) versus MET monotherapy (n=17), among newly-diagnosed type 2 diabetes mellitus (T2DM) enrolled (between 2012 and 2014) in the VERIFY study from Korea (n=39). Primary endpoint was time to initial treatment failure (TF) (glycosylated hemoglobin [HbA1c] ≥7.0% at two consecutive scheduled visits after randomization [end of period 1]). Time to second TF was assessed when both groups were receiving and failing on the combination (end of period 2). With EC the risk of initial TF significantly reduced by 78% compared to MET (n=3 [15%] vs. n=10 [58.7%], P=0.0228). No secondary TF occurred in EC group versus five patients (29.4%) in MET. Patients receiving EC treatment achieved consistently lower HbA1c levels. Both treatment approaches were well tolerated with no hypoglycaemic events. In Korean patients with newly diagnosed T2DM, EC treatment significantly and consistently improved the long-term glycaemic durability as compared with MET.

Background: Conventional diagnostic approaches for adrenal tumors require multi-step processes, including imaging studies and dynamic hormone tests. Therefore, this study aimed to discriminate adrenal tumors from a single blood sample based on the combination of liquid chromatography-mass spectrometry (LC-MS) and machine learning algorithms in serum profiling of adrenal steroids. Methods: The LC-MS-based steroid profiling was applied to serum samples obtained from patients with nonfunctioning adenoma (NFA, n=73), Cushing’s syndrome (CS, n=30), and primary aldosteronism (PA, n=40) in a prospective multicenter study of adrenal disease. The decision tree (DT), random forest (RF), and extreme gradient boost (XGBoost) were performed to categorize the subtypes of adrenal tumors. Results: The CS group showed higher serum levels of 11-deoxycortisol than the NFA group, and increased levels of tetrahydrocortisone (THE), 20α-dihydrocortisol, and 6β-hydroxycortisol were found in the PA group. However, the CS group showed lower levels of dehydroepiandrosterone (DHEA) and its sulfate derivative (DHEA-S) than both the NFA and PA groups. Patients with PA expressed higher serum 18-hydroxycortisol and DHEA but lower THE than NFA patients. The balanced accuracies of DT, RF, and XGBoost for classifying each type were 78%, 96%, and 97%, respectively. In receiver operating characteristics (ROC) analysis for CS, XGBoost, and RF showed a significantly greater diagnostic power than the DT. However, in ROC analysis for PA, only RF exhibited better diagnostic performance than DT. Conclusion The combination of LC-MS-based steroid profiling with machine learning algorithms could be a promising one-step diagnostic approach for the classification of adrenal tumor subtypes.

Glycemic variability is associated with the development of diabetic complications and hypoglycemia. However, the effect of sodium-glucose transporter 2 (SGLT2) inhibitors on glycemic variability is controversial. We aimed to examine the effect of dapagliflozin as an add-on therapy to insulin on the glycemic variability assessed using continuous glucose monitoring (CGM) in subjects with type 2 diabetes mellitus.

Glycemic variability is associated with the development of diabetic complications and hypoglycemia. However, the effect of sodium-glucose transporter 2 (SGLT2) inhibitors on glycemic variability is controversial. We aimed to examine the effect of dapagliflozin as an add-on therapy to insulin on the glycemic variability assessed using continuous glucose monitoring (CGM) in subjects with type 2 diabetes mellitus.

Background: Endothelial-to-mesenchymal transition (EndMT) contributes to inflammatory conditions inducing conversion of endothelial cells (ECs) into activated fibroblasts, promoting fibrotic diseases. Pro-inflammatory cytokine is the most potent inducer of EndMT. We investigated inhibition of interleukin-1β (IL-1β)-induced EndMT by gemigliptin, a dipeptidyl peptidase-IV inhibitor. Methods: We exposed human umbilical vein endothelial cells (HUVECs) to 10 ng/mL IL-1β/20 μM gemigliptin and analyzed the expression of endothelial, smooth muscle, mesenchymal, and osteoblastic markers, bone morphogenetic protein (BMP), Smad, and non-Smad signaling pathway proteins. Results: Morphological changes showed gemigliptin blocked IL-1β-induced EndMT, upregulated EC markers, and downregulated smooth muscle and mesenchymal markers. IL-1β activation of HUVECs is initiated by the BMP/Smad and non-smad BMP signaling pathways. Gemigliptin inhibited IL-1β induction of BMP2 and 7, activin receptor type IA, BMP receptor type IA, and BMP receptor type II. Reversal of IL-1β-mediated inhibition of BMP-induced Smad1/5/8, Smad2, and Smad3 phosphorylation by gemigliptin suggests involvement of the Smad pathway in gemigliptin action. In the non-Smad BMP pathway, gemigliptin treatment significantly increased the deactivation of extracellular regulated protein kinase (ERK), p38, and JNK by IL-1β. Gemigliptin treatment suppressed BMP-2-induced expression of key osteoblastic markers including osterix, runt-related transcription factor 2, and hepcidin during IL-1β-induced EndMT. Conclusion We demonstrated a novel protective mechanism of gemigliptin against fibrosis by suppressing IL-1β-induced EndMT.