Secular trends in the incidence and treatment patterns of primary hyperparathyroidism in Korea: a nationwide cohort study.

Data on epidemiology and secular trend in primary hyperparathyroidism (PHPT) in adults are relatively limited in Asian countries. This study aims to provide an overview of the secular trends in incidence, clinical characteristics, and treatment patterns of PHPT in South Korea. We used Korea's National Health Insurance Claim database (2005-2020) to identify newly diagnosed PHPT cases. Individuals with age below 19, fewer than 2 E21.0 diagnoses, fewer than 2 PTH measurements, secondary hyperparathyroidism, undergoing dialysis or kidney transplantation within a year of diagnosis, parathyroidectomy (PTX) within a year prior to the diagnosis code, and diagnosis of multiple endocrine neoplasm or parathyroid carcinoma were excluded from the analysis. A total of 6837 patients with PHPT (PTX, n = 2989; non-surgery, n = 3848) were compared with 1:10 age- and sex-matched controls (n = 68 370). The mean age of patients with PHPT was 56.0 years, with 77.4% being women. The annual incidence of PHPT increased from 0.23/100 000 persons in 2005 to 1.75 in 2020, with higher rate in women than in men. Compared with 2005-2010 (n = 675), the number of newly diagnosed PHPT cases increased up to 3.1-fold (n = 2119) in 2011-2015 and 6.0-fold (n = 4043) in 2016-2020 periods. Among all patients with PHPT, 43.7% of patients underwent PTX, with decrement of proportion of bilateral surgery among PTX group across time (11.9% in 2005-2010 to 8.9% in 2016-2020, P for trend .033). Among all patients with PHPT, non-surgery group increased from 41.6% in 2005-2010 to 58.0% in 2016-2020 (P for trend <.001). Patients with PHPT had higher odds of osteoporosis (odds ratio [OR] 7.03), renal stones (OR 10.55), chronic kidney diseases (OR 7.42), and cardiovascular, metabolic, and neurological conditions after adjustment for comorbidity index. In summary, the incidence of PHPT increased from 2005 to 2020 with predominance of non-surgical treatment, which calls for research focus on improving non-surgical management.

Association of sodium-glucose cotransporter 2 inhibitor use with risk of osteoporotic fracture among older women: A nationwide, population-based cohort study.

INTRODUCTION: We investigated the relationship between sodium-glucose cotransporter-2 inhibitor (SGLT2i) and fracture in elderly women diagnosed with type 2 diabetes mellitus (T2DM) and newly prescribed antidiabetic medications (ADMs). MATERIAL AND METHODS: We used the population-based cohort study data from the National Health Insurance Service of Korea (2013-2020). Women ≥65 years old with T2DM, who were newly prescribed ADMs other than glucagon-like peptide-1 receptor agonists and thiazolidinedione, and who had comprehensive health check-up data were included. RESULTS: A total of 1,333 SGLT2i users were matched in a 1:2 ratio with 2,626 non-SGLT2i users. After propensity score matching, mean age, body mass index, number of ADMs, and other covariates were well-balanced between SGLT2i users and non-SGLT2i users. During the follow-up period, a higher incidence of vertebral fractures in SGLT2i users than in non-SGLT2i users (incidence rate 19.2 vs. 13.8 per 1,000 person-years; hazard ratio 1.40, 95 % confidence interval 1.00-1.96, p = 0.049). No significant difference was noted in other types of fracture. CONCLUSION: SGLT2i use showed an increased risk of vertebral fracture than non-SGLT2i use in elderly women. Although further validation is required, SGLT2i should be cautiously prescribed in older women due to the potential association with fracture risk.

Risk of Fracture in Patients with Myasthenia Gravis: A Nationwide Cohort Study in Korea.

Myasthenia gravis (MG) is an autoimmune disorder that affects the neuromuscular junctions, resulting in muscle weakness and fatigue. Muscle weakness, restricted mobility, and frequent use of corticosteroids in patients with MG may predispose them to a higher risk of fractures. However, studies on the impact of MG on bone health and the associated fracture risk are scarce. Utilizing claim database of the Korean National Health Insurance Service collected between 2002 and 2020, we compared the risk of major osteoporotic fracture between 23 118 patients with MG and 115 590 individuals as an age- and sex-matched control group using multivariable Cox proportional hazard models. Over a median follow-up duration of 5.58 years, the MG group (mean age 53.7 years; 55% women) had higher risk of major osteoporotic fracture compared to controls (incidence rate 13.59 versus 9.74 per 10 000 person-years), which remained independent of age, sex, comorbidities, drug use including anti-osteoporotic agents, and previous fracture history (adjusted hazard ratio [aHR] 1.19, p < 0.001; subdistributed HR 1.14, p < 0.001 adjusted for mortality as competing risk). Subgroup analyses showed a greater association between MG and major osteoporotic fracture risk in younger (age 50 or younger) than older individuals (aHR 1.34 vs. 1.17) and in men compared to women (aHR 1.32 vs. 1.15; p for interaction <0.05 for all). An imminent divergence of the fracture risk curve between MG and controls was observed for vertebral fracture while there was time delay for non-vertebral sites, showing site-specific association. Factors associated with higher fracture risk in patients with MG were older age, female gender, high dose glucocorticoid use (> 7.5 mg/day), immunosuppressant use, and previous history of fracture. In summary, patients with MG had higher risk of major osteoporotic fracture compared to controls, which calls further preventive actions in this patient group.

Risk of dementia in primary aldosteronism compared with essential hypertension: a nationwide cohort study.

BACKGROUND: Although hypertension is a critical risk factor for dementia, the association between primary aldosteronism (PA) and dementia has been scarcely reported. We aimed to investigate whether the risk of dementia in patients with PA was elevated compared with patients with essential hypertension (EH). METHODS: From the National Health Insurance Claim database in Korea (2003-2017), 3,687 patients with PA (adrenalectomy [ADX], n = 1,339, mineralocorticoid receptor antagonist [MRA] n = 2,348) with no prior dementia were age- and sex-matched at a 1:4 ratio to patients with EH (n = 14,741). The primary outcomes were all-cause dementia events, including Alzheimer's disease, vascular dementia, or other dementia combined with a prescription of one or more medications for dementia (donepezil, galantamine, memantine, or rivastigmine). Multivariable Cox regression models were used to evaluate the hazard ratios (HRs) and 95% confidence intervals for the outcome incidence rates between patients with PA and their EH matches. RESULTS: During a median follow-up of 5.2 years, there were 156 cases of all-cause dementia (4.2%), 140 cases of Alzheimer's disease (3.8%), and 65 cases of vascular dementia (1.8%). Compared with EH, the risk of all-cause dementia was increased in treated PA (unadjusted hazard ratio [HR] 1.26; p < 0.011). Among PA, MRA group had higher risks of all-cause dementia, especially vascular dementia, adjusted for age, sex, income, comorbidities, and concurrent medication (adjusted HR 1.31; p = 0.027 and adjusted HR 1.62; p = 0.020, respectively) compared to EH. ADX group seemed to have a lower dementia risk than the EH group, but there was no statistical significance after full adjustment. This trend became more prominent when the dementia risks were evaluated from the time of hypertension diagnosis rather than treatment initiation for PA. CONCLUSION: The findings of this cohort study suggest that PA, especially the MRA group, is associated with an increased risk of dementia. Monitoring cognitive function in PA patients even after treatment initiation might be warranted to prevent dementia.

Elevated gamma-glutamyl transpeptidase level is associated with an increased risk of hip fracture in postmenopausal women.

The aim of this study was to evaluate the association between gamma-glutamyl transferase (GGT) levels and the risk of hip fracture among middle-aged women by using the Korean National Health Insurance Service claims database from 2002 to 2015. After exclusion of those with any chronic liver disease, heavy alcohol consumption, any missing values required for our analysis, or GGT levels less than 1 or greater than 99 percentile, we classified subjects into three groups according to baseline GGT levels. A total of 127,141 women aged 50 years or older were included for analysis (GGT range: 8-106 U/L). During an average 12.1 years of follow-up, 2758 patients sustained hip fractures (2.17%). Compared with the group in the lowest tertile, the group in the highest tertile had the highest cumulative incidence of hip fracture. One log-unit increase in GGT was associated with a 17% increased risk of hip fracture. Subgroup analysis by BMI (≥ 25 vs. < 25 kg/m2), presence of diabetes, levels of other liver enzymes, and alcohol consumption level did not show significant effect modification. In summary, elevated baseline GGT level was associated with an increased risk of hip fracture in postmenopausal women, independent of alcohol consumption and chronic liver disease.

Operational Definition Identifying Osteoporotic Vertebral Fractures in the Claims Database.

BACKGROUND: We analyzed the International Classification of Diseases, 10th edition (ICD-10) diagnostic codes, procedure codes, and radiographic image codes for vertebral fracture (VF) used in the database of Health Insurance Review and Assessment Service (HIRA) of Korea to establish a validated operational definition for identifying patients with osteoporotic VF in claims data. METHODS: We developed three operational definitions for detecting VFs using 9 diagnostic codes, 5 procedure codes and 4 imaging codes. Medical records and radiographs of 2,819 patients, who had primary and subordinated codes of VF between January 2016 and December 2016 at two institutions, were reviewed to detect true vertebral fractures. We evaluated the sensitivity and positive predictive value (PPV) of the operational definition in detecting true osteoporotic VF and obtained the receiver operating characteristic (ROC) curve. RESULTS: Among the 2,819 patients who had primary or secondary diagnosis codes for VF, 995 patients satisfied at least one of the criteria for the operational definition of osteoporotic VF. Of these patients, 594 were judged as having true fractures based on medical records and radiographic examinations. The sensitivity and PPV were 62.5 (95% confidence interval [CI], 59.4-65.6) and 59.7(95% CI, 56.6-62.8) respectively. In the receiver operating characteristic analysis, area under the curve (AUC) was 0.706 (95% CI, 0.688-0.724). CONCLUSION: Our findings demonstrate the validity of our operational definitions to identify VFs more accurately using claims data. This algorithm to identify VF is likely to be useful in future studies for diagnosing osteoporotic VF.

Time-Dependent Risk of Atrial Fibrillation in Patients With Primary Aldosteronism After Medical or Surgical Treatment Initiation.

[Figure: see text].Increased risk of atrial fibrillation was reported in patients with primary aldosteronism. However, data are limited regarding the time-dependent risk of atrial fibrillation in surgically or medically treated primary aldosteronism. From the National Health Insurance Claim database in Korea (2003­2017), a total of 1418 patients with primary aldosteronism (adrenalectomy [ADX], n=755, mineralocorticoid receptor antagonist n=663) were age- and sex-matched at a 1:5 ratios to patients with essential hypertension (n=7090). Crude incidence of new onset atrial fibrillation was 2.96% in primary aldosteronism and 1.97% in essential hypertension. Because of nonproportional hazard observed in new onset atrial fibrillation, analysis time was split at 3 years. Compared with essential hypertension, risk of new onset atrial fibrillation peaked at 1 year gradually declined but remained elevated up to 3 years in overall treated primary aldosteronism (adjusted hazard ratio [aHR] 3.02; P<0.001) as well as in both ADX (aHR, 3.54; P<0.001) and mineralocorticoid receptor antagonist groups (aHR 2.27; P=0.031), which became comparable to essential hypertension afterward in both groups (ADX aHR, 0.38; P=0.102; mineralocorticoid receptor antagonist aHR, 0.60; P=0.214). Nonetheless, mineralocorticoid receptor antagonist group was associated with increased risk of nonfatal stroke (aHR, 1.21; P=0.031) compared with essential hypertension, whereas ADX was not (aHR, 1.26; P=0.288). Our results suggest the risk of new-onset atrial fibrillation remained elevated up to 3 years in treated primary aldosteronism compared with essential hypertension, which declined to comparable risk in essential hypertension thereafter. Monitoring for atrial fibrillation up to 3 years after treatment, particularly ADX, might be warranted.

Gender and age differences in the prevalence and associated factors of metabolic syndrome among children and adolescents in South Korea.

PURPOSE: This study examined the prevalence of metabolic syndrome (MetS) in South Korean children and adolescents by gender and age and analyzed gender-specific factors associated with MetS. METHODS: This study used data on children aged 10-18 years from the Korea National Health and Nutrition Examination Survey (KNHANES) from 2010 to 2015. Analyses included descriptive statistics, the independent t-test, the x 2 test, and univariate logistic regression analysis (p<.050). RESULTS: The prevalence of MetS was 4.8% in boys and 3.4% in girls. The prevalence was higher in girls up to the age of 12, but higher in boys who were 13 or older. Abdominal obesity was frequent in girls, whereas low high-density lipoprotein cholesterol (HDL-C) and elevated blood pressure were more common in boys. Higher body mass index, waist-to-height ratio, waist circumference, blood pressure, triglycerides, HDL-C, perceived "fat" body shape, and weight loss efforts were associated with MetS in both genders. Increasing age, having one meal per day, and weight maintenance were associated factors unique to boys. Fasting plasma glucose, familial medical history of low HDL-C, and perceived "thin" body shape were associated factors in girls. CONCLUSION: Gender and age differences should be considered in the risk assessment and prevention of MetS.

Uses of Inflammatory Markers for Differentiation of Intrahepatic Mass-Forming Cholangiocarcinoma from Liver Abscess: Case-Control Study.

BACKGROUND: Pyogenic liver abscess (LA) is difficult to distinguish from intrahepatic mass-forming cholangiocarcinoma (IMCC) in the emergency department (ED). We evaluated the predictive ability of white blood cells (WBC) and C-reactive protein (CRP) levels, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and delta neutrophil index (DNI) in LA and IMCC in the ED. METHODS: Forty patients with IMCC between January 2011 and December 2018 were included in this study. For each patient with IMCC, two control patients with LA were enrolled based on matching age and sex,-i.e., 80 patients with LA. RESULTS: Inflammatory markers, including WBC, PLR, NLR, DNI, and CRP were significantly higher in the LA group than in the IMCC group. For both groups, the area under the curve (AUC) of the initial CRP value was significantly higher (AUC: 0.909) than that of the initial serum WBC count, PLR, and DNI levels. On multivariable logistic regression analysis with inflammatory markers, serum CRP (odds ratio, 1.290; 95% confidence interval, 1.148-1.449, p < 0.001) was the only significant predictor for differentiation between the LA and IMCC groups. CONCLUSION: Serum CRP may be a potential inflammatory marker to differentiate IMCC from LA in the ED.

Beta-blocker Therapy at Discharge in Patients with Acute Heart Failure and Atrial Fibrillation.

BACKGROUND: ß-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.

Seasonal variation in acute post-cataract surgery endophthalmitis incidences in South Korea.

PURPOSE: Previous studies have reported conflicting results on the influence of seasons on post-cataract surgery endophthalmitis incidences. This study aimed to investigate the seasonality associated with the incidence of postoperative endophthalmitis, and to evaluate its association with climate variables in South Korea. SETTING: South Korea. DESIGN: Retrospective cohort study. METHODS: The postoperative endophthalmitis incidences were identified using the Health Insurance Review and Assessment Service claim data from July 2014 to June 2017. The monthly climate data were obtained from the Korea Meteorological Administration. The incidences of endophthalmitis were analyzed by the month of the year, and by the season. The association between postoperative endophthalmitis and the climatic variables, including mean temperature, relative humidity, precipitation, and hours of sunshine, was investigated. RESULTS: The incidences were the highest in July, and they were the most prevalent during the summer months, although fewer cataract surgeries were performed in the summer months than during the rest of the year. The postoperative endophthalmitis incidences tended to increase with increasing relative humidity and increasing precipitation. CONCLUSIONS: The incidences of post-cataract surgery endophthalmitis peaked during the hot and humid months. Understanding the seasonal and climatic influences on postoperative infection might help in risk stratification and outcome improvisation after the cataract surgery is performed.

Endophthalmitis after Cataract Surgery in Korea: A Nationwide Study Evaluating Incidence and Risk Factors in a Korean Population.

PURPOSE: To assess the nationwide rate of acute postoperative endophthalmitis (APE) after cataract extraction in Korea and to evaluate potential risk factors thereof. MATERIALS AND METHODS: Nationwide insurance claims data from July 2014 to June 2017 were reviewed. All patients with phacoemulsification or extracapsular/intracapsular cataract extraction were included. Exclusion criteria were combined glaucoma surgery or total vitrectomy or when the patient had a history of intraocular foreign body. RESULTS: In total, 1505103 cases (982203 patients) were included. APE developed in 953 cases (938 patients) with an overall incidence of 0.063%. After adjusting for possible confounding factors, male sex [odds ratio (OR) 1.42; 95% confidence interval (CI) 1.25-1.61; p<0.001], primary clinical setting, operations performed in non-major cities, usage of sutures (OR 2.82; 95% CI 2.13-3.74; p<0.001), anterior vitrectomy (OR 8.71; 95% CI 6.71-11.32; p<0.001), aphakic cataract surgery (OR 1.52; 95% CI 1.03-2.22; p=0.033), hypertension (OR 1.40; 95% CI 1.18-1.66; p<0.001), diabetes (OR 1.59; 95% CI 1.31-1.93; p<0.001), and chronic renal failure (OR 1.28; 95% CI 1.01-1.62; p=0.039) were found to be related to APE development. CONCLUSION: The incidence of APE after cataract extraction was consistent with reports from other studies. Additional research is needed to determine the relationship of newly found risk factors, such as hypertension, primary clinical setting, chronic renal failure, and usage of suturing, with APE development.

Immediate multivessel intervention versus culprit-vessel intervention only in patients with ST-elevation myocardial infarction and multivessel coronary disease: data from the prospective KAMIR-NIH registry.

BACKGROUND: The safety and efficacy of immediate multivessel coronary intervention (MVI) remain controversial in patients with ST-elevation myocardial infarction (STEMI) and multivessel disease (MVD). This study aimed to investigate the clinical outcomes of immediate MVI compared with culprit-vessel intervention only (CVI-O) in diverse subgroups with STEMI and MVD. PATIENTS AND METHODS: We compared immediate MVI (n=260) and CVI-O (n=931) regarding 1-year major adverse cardiac event rates for cardiac death, recurrent myocardial infarction (MI), and repeat revascularization in 1191 STEMI patients with MVD using data from the Korea Acute Myocardial Infarction-National Institutes of Health registry (2011-2015). High-risk patients and those who underwent a staged procedure were excluded from the analysis. Furthermore, propensity score matching and stratified subgroup analyses were performed. RESULTS: Immediate MVI and CVI-O groups had similar 1-year major adverse cardiac event rates [7.7 vs. 8.9%, hazard ratio (HR): 0.86, 95% confidence interval (CI): 0.50-1.47, log-rank P=0.5628]. No difference was found between the groups in terms of the 1-year rate of cardiac death (2.9 vs. 1.3%, HR: 2.24, 95% CI: 0.75-6.67) or recurrent MI (2 vs. 1.5%, HR: 1.41, 95% CI: 0.45-4.44). However, repeat revascularization occurred less frequently in the immediate MVI group than in the CVI-O group (2.0 vs. 5.7%, HR: 0.35, 95% CI: 0.13-0.90, log-rank P=0.0142). These findings were found to be consistent across a broad spectrum of subgroups. CONCLUSION: Compared with CVI-O, immediate MVI did not improve 1-year net clinical outcomes in stable STEMI patients with MVD. The only benefit found was a reduced repeat revascularization in immediate MVI.

Effects of Altered Calcium Metabolism on Cardiac Parameters in Primary Aldosteronism.

BACKGROUND: Increasing evidence supports interplay between aldosterone and parathyroid hormone (PTH), which may aggravate cardiovascular complications in various heart diseases. Negative structural cardiovascular remodeling by primary aldosteronism (PA) is also suspected to be associated with changes in calcium levels. However, to date, few clinical studies have examined how changes in calcium and PTH levels influence cardiovascular outcomes in PA patients. Therefore, we investigated the impact of altered calcium homeostasis caused by excessive aldosterone on cardiovascular parameters in patients with PA. METHODS: Forty-two patients (mean age 48.8±10.9 years; 1:1, male:female) whose plasma aldosterone concentration/plasma renin activity ratio was more than 30 were selected among those who had visited Severance Hospital from 2010 to 2014. All patients underwent adrenal venous sampling with complete access to both adrenal veins. RESULTS: The prevalence of unilateral adrenal adenoma (54.8%) was similar to that of bilateral adrenal hyperplasia. Mean serum corrected calcium level was 8.9±0.3 mg/dL (range, 8.3 to 9.9). The corrected calcium level had a negative linear correlation with left ventricular end-diastolic diameter (LVEDD, ρ=-0.424, P=0.031). Moreover, multivariable regression analysis showed that the corrected calcium level was marginally associated with the LVEDD and corrected QT (QTc) interval (ß=-0.366, P=0.068 and ß=-0.252, P=0.070, respectively). CONCLUSION: Aldosterone-mediated hypercalciuria and subsequent hypocalcemia may be partly involved in the development of cardiac remodeling as well as a prolonged QTc interval, in subjects with PA, thereby triggering deleterious effects on target organs additively.

Relative Risk and Clinical Severity Assessment in Patients with Non-Oral Route Organophosphate Poisoning Compared with Oral Route Poisoning.

PURPOSE: Organophosphates, commonly used in agricultural pesticides, pose high risks and incidences of poisoning. In the present study, we investigated the relative risk and clinical severity, including laboratory results, of non-oral route poisoning (NORP) patients, compared to oral route poisoning (ORP) patients. MATERIALS AND METHODS: A single institutional toxicology database registry was utilized to gain information on clinical laboratory results on organophosphate poisoning patients who visited the emergency department (ED) between January 2000 and October 2016. Clinical outcomes, such as mortality and complication rates, were compared using 1:2 propensity score matching in the total cohort. RESULTS: Among a total of 273 patients in our study, 34 experienced NORP. After 1:2 propensity score matching, rates of respiratory complications and mortality were higher in the ORP group than in the NORP group. However, there was no difference in hospitalization time and time spent in the intensive care unit between the two groups. Compared with ORP patients after matching, the relative risk of mortality in NORP patients was 0.34, and the risk of respiratory distress was 0.47. The mean level of pseudocholinesterase was significantly higher in the NORP group than in the ORP group, while recovery rates were similar between the two groups. CONCLUSION: Although the majority of NORP patients were admitted to the ED with unintentional poisoning and the relative risk of NORP was lower than that for ORP, we concluded that NORP is as critical as ORP. Considerable medical observation and intensive therapeutic approaches are also needed for NORP patients.

Hot snare polypectomy with or without saline solution/epinephrine lift for the complete resection of small colorectal polyps.

BACKGROUND AND AIMS: The criteria for a standard polypectomy technique for complete removal of small colorectal polyps has not yet been established. This study aimed to compare the complete resection rate of hot snare polypectomy (HSP) with that of EMR for small, sessile, or flat polyps. METHODS: Patients with 5- to 9-mm non-pedunculated colorectal polyps were prospectively randomized to the HSP or EMR group. The presence of residual polyps was assessed by performing histologic assessment of 4-quadrant forceps biopsy specimens taken from the edges of the polypectomy site. The primary outcome was the complete resection rate after HSP or EMR; the secondary outcomes were the proportion of procedure-related adverse events and specimen-loss rate. Sample size was estimated using a superiority trial design. We assumed that the complete resection rate of the EMR group would be at least 8% higher than that of the HSP group. RESULTS: A total of 382 polyps in 269 patients were assessed and randomly assigned to each method using 4 × 4 block randomization. Of these, 353 polyps were finally analyzed based on the pathology results. The mean polyp size was 6.3 ± 1.3 mm. The complete resection rate did not differ between the HSP and EMR groups (88.4% [152/172] vs 92.8% [168/181], respectively; P = .2). The intraprocedural bleeding rate, immediately after polypectomy, was significantly higher in the HSP group than in the EMR group (5.2% vs 0.6%, respectively; P = .009). However, clinically significant bleeding and tissue retrieval failure rates did not differ between the groups. In the multivariate logistic regression analysis, sessile serrated adenoma/polyps or hyperplastic polyps were almost 3 times (odds ratio, 2.824; 95% confidence interval, 1.03-7.75; P = .044) more likely to be incompletely resected compared with other conventional adenomatous polyps. Except for pathology, we found no significant independent predictors for incomplete resection. CONCLUSION: EMR for small non-pedunculated colorectal polyps is not superior to HSP in terms of complete resection or safety. Both methods can be performed according to the endoscopist's preference. (Clinical trial registration number: KCT0001640; cris.nih.go.kr.).