Background and Objectives: Beta-blockers (BBs) improve prognosis in heart failure (HF), which is mediated by lowering heart rate (HR). However, HR has no prognostic implication in atrial fibrillation (AF) and also BBs have not been shown to improve prognosis in heart failure with preserved ejection fraction (HFpEF) with AF. This study assessed the prognostic implication of BB in HFpEF with AF according to discharge HR. Methods: From the Korean Acute Heart Failure Registry, 687 patients with HFpEF and AF were selected. Study subjects were divided into 4 groups based on 75 beats per minute (bpm) of HR at discharge and whether or not they were treated with BB at discharge. Results: Of the 687 patients with HFpEF and AF, 128 (36.1%) were in low HR group and 121 (36.4%) were in high HR group among those treated with BB at discharge. In high HR group, HR at discharge was significantly faster in BB non-users (85.5±9.1 bpm vs. 89.2±12.5 bpm, p=0.005). In the Cox model, BB did not improve 60-day rehospitalization (hazard ratio, 0.93;95% confidence interval [95% CI], 0.35–2.47) or mortality (hazard ratio, 0.77; 95% CI, 0.22– 2.74) in low HR group. However, in high HR group, BB treatment at discharge was associated with 82% reduced 60-day HF rehospitalization (hazard ratio, 0.18; 95% CI, 0.04–0.81), but not with mortality (hazard ratio, 0.77; 95% CI, 0.20–2.98). Conclusions In HFpEF with AF, in patients with HR over 75 bpm at discharge, BB treatment at discharge was associated with a reduced 60-day rehospitalization rate.

Background/Aims: While distal radial artery (DRA) access is increasingly being used for diagnostic coronary angiography, limited information is available regarding DRA size. We aimed to determine the DRA reference diameters of Korean patients and identify the predictors of DRA diameter < 2.3 mm. Methods: The outer bilateral DRA diameters were assessed using a linear ultrasound probe in 1,162 consecutive patients who underwent transthoracic echocardiography. The DRA diameter was measured by the perpendicular angle in the dorsum of the hand, and the average values were compared by sex. DRA diameter < 2.3 mm was defined as unsuitable for routine diagnostic coronary angiography using a 5 Fr introducer sheath. Results: The mean DRA diameters were 2.31 ± 0.43 mm (right) and 2.35 ± 0.45 mm (left). The DRA was smaller in women than men (right: 2.15 ± 0.38 mm vs. 2.43 ± 0.44 mm, p < 0.001; left: 2.18 ± 0.39 mm vs. 2.47 ± 0.45 mm, p < 0.001). The DRA diameter was approximately 20% smaller than the radial artery diameter. A total of 630 (54.2%) and 574 (49.4%) patients had DRA diameter < 2.3 mm in the right and left hands, respectively. Female sex, low body mass index (BMI), and low body surface area (BSA) were significant predictors of DRA diameter < 2.3 mm. Conclusions We provided reference DRA diameters for Korean patients. Approximately 50% of the studied patients had DRA diameter < 2.3 mm. Female sex, low BMI, and low BSA remained significant predictors of DRA diameter < 2.3 mm.

Background/Aims: Inflammatory bowel disease (IBD) is associated with the occurrence of venous thromboembolism (VTE). However, to date, there have been few studies on the risk of VTE in Asian IBD patients. We aimed to estimate the incidence of VTE in Asian IBD patients and to determine if IBD is related to increased VTE risk. Methods: We performed a population-based cohort study between 2004 and 2015 using Korean National Health Insurance data. IBD and VTE were defined by ICD-10 codes. Incidence rates of VTE were calculated among patients with IBD and among age- and sex-matched controls. Hazard ratios were estimated using Cox regression with adjustment for multiple variables. We performed additional analyses stratifying by age, sex, Charlson comorbidity index (CCI) score, and disease type. Results: Among the 45,037 patients with IBD (IBD cohort) and 133,019 matched controls (nonIBD cohort) included in our analysis, 411 IBD patients and 641 controls developed VTE. The IBD cohort had a higher incidence rate ratio and risk of VTE than the non-IBD cohort (incidence rate ratio: 1.92 and hazard ratio: 1.93). Older age, female sex, higher CCI scores, cardiovascular disease, chronic kidney disease, use of steroids, and hospitalization were significant risk factors for VTE in patients with IBD. Conclusions The IBD patients in this study were approximately two times more likely to develop VTE than the non-IBD individuals. Our findings support the need for thromboprophylaxis in Asian IBD patients with various factors that further increase the risk of VTE.

Background: This study evaluated the relationship between guideline adherence for heart failure (HF) with reduced ejection fraction (HFrEF) at discharge and relevant clinical outcomes in patients with acute HF with preserved ejection fraction (HFpEF) with or without atrial fibrillation (AF). Methods: We analyzed Korean Acute Heart Failure Registry data for 707 patients with HFpEF with documented AF and 687 without AF. Guideline adherence was defined as good or poor according to the prescription of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, and mineralocorticoid receptor antagonists. Anticoagulation adherence was also incorporated for the AF group. Results: Among patients with normal sinus rhythm, those with poor guideline adherence had a reduced prevalence of comorbidities and favorable clinical characteristics when compared with those with good guideline adherence. Using inverse probability of treatment weighting (IPTW) to address the bias of nonrandom treatment assignment, good adherence was associated with a poor 60-day composite endpoint in the multivariable Cox model (weighted hazard ratio [wHR], 1.74; 95% confidence interval [CI], 1.01–3.00; P = 0.045). For patients with AF, baseline clinical characteristics were similar according to the degree of adherence. The IPTW-adjusted analysis indicated that good adherence was significantly associated with the 60-day composite endpoint (wHR, 0.47; 95% CI, 0.27–0.79; P = 0.005). In the analysis excluding warfarin, good adherence was associated with 60-day rehospitalization (wHR, 0.60; 95% CI, 0.37–0.98; P = 0.040), 1-year re-hospitalization (wHR, 0.67; 95% CI, 0.48–0.93; P = 0.018), and the composite endpoint (wHR, 0.77; 95% CI, 0.59–0.99; P = 0.041). Conclusion Our findings indicate that good adherence to guidelines for HFrEF is associated with a better 60-day composite endpoint in patients with HFpEF with AF.

Purpose: This study aimed to determine whether the use of drugs in the treatment of inflammatory bowel disease is related to the risk of colorectal cancer using a Cox proportional hazards model with the landmark method to minimize immortal time bias. Materials and Methods: This study was conducted as national cohort-based study using data from Korea’s Health Insurance Corporation. Newly diagnosed patients with inflammatory bowel disease from 2006 to 2010 were monitored for colorectal cancer until 2015. Hazard ratios and 95% confidence intervals were calculated and compared with the incidence of colorectal cancer with or without medications by applying various landmark points. Results: In patients with Crohn’s disease, the prevention of colorectal cancer in the group exposed to immunomodulators was significant in the basic Cox model; however, the effect was not statistically significant in the model using the landmark method. The preventive effect of 5-aminosalicylic acid in patients with ulcerative colitis was significant in the basic and 6-month landmark point application models, but not in the remaining landmark application models. Conclusion In patients with inflammatory bowel disease, the preventive effect of drug exposure on colorectal cancer varies depending on the application of the landmark method. Hence, the possibility of immortal time bias should be considered.

Purpose: This study aimed to determine whether the use of drugs in the treatment of inflammatory bowel disease is related to the risk of colorectal cancer using a Cox proportional hazards model with the landmark method to minimize immortal time bias. Materials and Methods: This study was conducted as national cohort-based study using data from Korea’s Health Insurance Corporation. Newly diagnosed patients with inflammatory bowel disease from 2006 to 2010 were monitored for colorectal cancer until 2015. Hazard ratios and 95% confidence intervals were calculated and compared with the incidence of colorectal cancer with or without medications by applying various landmark points. Results: In patients with Crohn’s disease, the prevention of colorectal cancer in the group exposed to immunomodulators was significant in the basic Cox model; however, the effect was not statistically significant in the model using the landmark method. The preventive effect of 5-aminosalicylic acid in patients with ulcerative colitis was significant in the basic and 6-month landmark point application models, but not in the remaining landmark application models. Conclusion In patients with inflammatory bowel disease, the preventive effect of drug exposure on colorectal cancer varies depending on the application of the landmark method. Hence, the possibility of immortal time bias should be considered.

Background: This study evaluated the relationship between guideline adherence for heart failure (HF) with reduced ejection fraction (HFrEF) at discharge and relevant clinical outcomes in patients with acute HF with preserved ejection fraction (HFpEF) with or without atrial fibrillation (AF). Methods: We analyzed Korean Acute Heart Failure Registry data for 707 patients with HFpEF with documented AF and 687 without AF. Guideline adherence was defined as good or poor according to the prescription of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, and mineralocorticoid receptor antagonists. Anticoagulation adherence was also incorporated for the AF group. Results: Among patients with normal sinus rhythm, those with poor guideline adherence had a reduced prevalence of comorbidities and favorable clinical characteristics when compared with those with good guideline adherence. Using inverse probability of treatment weighting (IPTW) to address the bias of nonrandom treatment assignment, good adherence was associated with a poor 60-day composite endpoint in the multivariable Cox model (weighted hazard ratio [wHR], 1.74; 95% confidence interval [CI], 1.01–3.00; P = 0.045). For patients with AF, baseline clinical characteristics were similar according to the degree of adherence. The IPTW-adjusted analysis indicated that good adherence was significantly associated with the 60-day composite endpoint (wHR, 0.47; 95% CI, 0.27–0.79; P = 0.005). In the analysis excluding warfarin, good adherence was associated with 60-day rehospitalization (wHR, 0.60; 95% CI, 0.37–0.98; P = 0.040), 1-year re-hospitalization (wHR, 0.67; 95% CI, 0.48–0.93; P = 0.018), and the composite endpoint (wHR, 0.77; 95% CI, 0.59–0.99; P = 0.041). Conclusion Our findings indicate that good adherence to guidelines for HFrEF is associated with a better 60-day composite endpoint in patients with HFpEF with AF.

Growth hormone (GH) deficiency is caused by congenital or acquired causes and occurs in childhood or adulthood. GH replacement therapy brings benefits to body composition, exercise capacity, skeletal health, cardiovascular outcomes, and quality of life. Before initiating GH replacement, GH deficiency should be confirmed through proper stimulation tests, and in cases with proven genetic causes or structural lesions, repeated GH stimulation testing is not necessary. The dosing regimen of GH replacement therapy should be individualized, with the goal of minimizing side effects and maximizing clinical improvements. The Korean Endocrine Society and the Korean Society of Pediatric Endocrinology have developed a position statement on the diagnosis and treatment of GH deficiency. This position statement is based on a systematic review of evidence and expert opinions.

Background: β-blockers (BBs) are considered primary therapy in stable heart failure (HF) with reduced ejection fraction (HFrEF) without atrial fibrillation (AF); evidence-based benefits of BB on outcome have been documented. However, BBs have not been shown to improve mortality or reduce hospital admissions in HF patients with AF. This study assessed the relationship between BBs at discharge and relevant clinical outcomes in acute heart failure (AHF) patients with AF. Methods: From the Korean Acute Heart Failure Registry, 936 HFrEF and 639 HF patients with preserved ejection fraction (HFpEF) and AF were selected. Propensity score (PS) matching accounted for BB selection bias when assessing associations. Results: BB-untreated patients in the overall cohort of HFrEF and HFpEF had greater deteriorated clinical and laboratory characteristics. In the 670 PS-matched cohort of HFrEF patients, incidences of all clinical events at 60 days and 1 year were not different according to use of BBs. In the 470 PS-matched cohort of HFpEF, rehospitalization and composite outcome at 6 months and 1 year more frequently occurred in non-users of BBs. After adjusting for covariates in the multivariable Cox model of matched cohorts, BB was not associated with clinical outcomes at 60 days and 1 year in HFrEF with AF patients. In HFpEF patients with AF, BB use was associated with reduced 6-month (hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.20–0.74) and 1-year rehospitalization (HR, 0.53; 95% CI, 0.34–0.82). Conclusion In the HFrEF with AF PS-matched cohort, the use of BBs at discharge was not associated with clinical outcome. However, in HFpEF with AF, the use of BB was associated with reduced rehospitalization during the 6-month and 1-year follow up.

BACKGROUND/AIMS: Despite the many reports of colonoscopy complications worldwide, few studies have been performed at the population level in Korea. In this study, a population-based study was performed to evaluate the incidence of post-colonoscopy perforations compared to a control group. METHODS: Between January 2011 and December 2011, data for all cases (age over 45) who underwent a colonoscopy were collected from National Health Insurance Service using a random sampling method. The clinical characteristics and perforation incidence (within 30 days after the colonoscopy) of cases were identified, and cases were then compared with controls who had not undergone a colonoscopy. RESULTS: Among 1,380,000 subjects, 31,177 cases and 62,354 controls were identified. Perforation occurred in 14 patients (0.04%) in the case group and one patient (<0.01%) in the control group (RR, 28.0; 95% CI 3.7–212.9, p<0.001). Subgroup analysis was followed according to the endoscopic procedure, gender and age. In subgroup analysis, colonoscopy-associated perforations occurred more in the therapeutic procedure (RR, 26; 95% CI 1.46–461.46), male (RR, 50; 95% CI 2.96–844.41), and age of 45–60 years (RR, 30; 95% CI 1.71–525.23). CONCLUSIONS: A colonoscopy procedure is related to an increased risk of perforation at the population level. In addition, the therapeutic procedure, male, and age of 45-60 years appeared to be associated with an increased risk of perforation.
Case-Control Studies ; Cohort Studies ; Colonoscopy ; Humans ; Incidence ; Intestinal Perforation ; Korea ; Male ; Methods ; National Health Programs ; Retrospective Studies