Impact of COVID-19 pandemic on the incidence and severity of myasthenia gravis in Korea: using National Health Insurance Service database.

Background: This study investigated the impact of COVID-19 pandemic on the incidence and severity of myasthenia gravis (MG) using the National Health Insurance Service (NHIS) database in Korea. Methods: We analyzed data from patients with MG in the NHIS registry from 2015 to 2021. MG was defined as (1) patients aged ≥18 years with the G70.0 code, and (2) patients who visited tertiary hospitals regarldless of department in Korea (outpatient clinics at least twice or hospitalization at least once), and (3) patients who were prescribed pyridostigmine as MG medications at least once. We designated pre-COVID-19 as 2019 and post-COVID-19 as 2021 and analyzed the MG incidence and prevalence in 2019 and 2021. We compared the clinical data of patients with MG between the two years. MG exacerbation was defined as the administration of intravenous immunoglobulin or plasma exchange. Analysis of COVID-19 cases was conducted using an integrated database from the Korea Disease Control and Prevention Agency and NHIS. Patients with MG were divided into two groups according to COVID-19 status to compare their clinical characteristics. Results: A total of 6,888 and 7,439 MG cases were identified in 2019 and 2021, respectively. The standardized incidence was 1.56/100,000 in 2019, decreasing to 1.21/100,000 in 2021. Although the frequency of MG exacerbations was higher in 2019, there were no differences in the number and duration of hospitalizations, duration of ICU stays, hostalization expense, and mortality between 2019 and 2021. Patients with MG and COVID-19 had a higher frequency of MG exacerbations than patients without COVID-19, but there were no differences in the number and duration of hospitalizations, hospitalization expense, and mortality. Conclusion: This study was the first nationwide population-based epidemiological study of MG during COVID-19 pandemic in Korea. The incidence of MG decreased during COVID-19 pandemic, and the severity of MG was not affected by COVID-19.

Thiazide-associated hyponatremia in arterial hypertension patients: A nationwide population-based cohort study.

OBJECTIVE: Thiazides are the first-line treatment for hypertension, however, they have been associated with hospitalizations for thiazide-associated hyponatremia (TAH). The aim of this study was to evaluate the risk of TAH and other drug-associated hyponatremia in a Korean population. METHODS: The study used big data from the National Health Insurance Sharing Service of 1,943,345 adults treated for hypertension from January 2014 to December 2016. The participants were divided into two groups based on the use of thiazides. Cox proportional hazard models were used to identify independent risk factors for the occurrence of hyponatremia. RESULTS: The study found that hyponatremia-related hospitalizations were significantly higher in the thiazide group than the control group (2.19% vs. 1.45%). The risk increased further with concurrent use of other diuretics or desmopressin, and thiazide+spironolactone+desmopressin and hospitalization risk further increased (4.0 and 6.9 times). Multivariate analysis showed that hyponatremia occurrence increased with age, diabetes mellitus, depression, and thiazide use (hazard ratio = 1.436, p < 0.001). The thiazide group had better 6-year overall survival than the control group but had more fractures and hyponatremia. CONCLUSIONS: Thiazide use is associated with an increased risk of hyponatremia and related complications. However, the mortality rate decreased in those who received thiazides, suggesting that thiazide use itself is not harmful and may help decrease complications and improve prognosis with proper, cautious use in high-risk patients.

Risk of cardiovascular disease with high-dose versus low-dose use of non-steroidal anti-inflammatory drugs in ankylosing spondylitis.

OBJECTIVE: To investigate the risk of cardiovascular disease (CVD) associated with increasing dose of a non-steroidal anti-inflammatory drug (NSAID) in patients with ankylosing spondylitis (AS). METHODS: Using the Korean National Health Insurance database, patients newly diagnosed with AS without prior CVD between 2010 and 2018 were included in this nationwide cohort study. The primary outcome was CVD, a composite outcome of ischaemic heart disease, stroke or congestive heart failure. Exposure to NSAIDs was evaluated using a time-varying approach. The dose of NSAIDs was considered in each exposure period. Cox proportional hazard regression was used to investigate the risk of CVD associated with NSAID use. RESULTS: Of the 19 775 patients (mean age, 36 years; 75% were male), 19 706 received NSAID treatment. During follow-up period of 98 290 person-years, 1663 cases of CVD occurred including 1157 cases of ischaemic heart disease, 301 cases of stroke and 613 cases of congestive heart failure. Increasing dose of NSAIDs was associated with incident CVD after adjusting for confounders (adjusted HR (aHR) 1.10; 95% CI 1.08 to 1.13). Specifically, increasing dose of NSAIDs was associated with incident ischaemic heart disease (aHR 1.08; 95% CI 1.05 to 1.11), stroke (aHR 1.09; 95% CI 1.04 to 1.15) and congestive heart failure (aHR 1.12; 95% CI 1.08 to 1.16). The association between NSAID dose and higher CVD risk was consistent in different subgroups. CONCLUSION: In a real-world AS cohort, higher dose of NSAID treatment was associated with a higher risk of CVD, including ischaemic heart disease, stroke and congestive heart failure.

Selective estrogen receptor modulators (SERMs) with vitamin D composite agent can prevent fracture better than SERMs treatment: based on the National Health Claims Database 2017-2019.

With the analysis of nationwide health claim data, treatment with the composite agent of SERMs and vitamin D reduces the risk of osteoporotic fracture and hip fracture better compared to SERMs treatment in women with osteoporosis aged ≥ 50 years. PURPOSE: This study compared the potential of the composite agent of selective estrogen receptor modulators (SERMs) and vitamin D (SERM + VitD) with that of SERMs-only for fracture prevention and mortality reduction in women aged ≥ 50 years. METHODS: The incidence of osteoporotic fracture (fractures of the vertebrae, hip, wrist, or humerus) and all-cause death after treatment with SERM + VitD and SERMs were characterized using the Korean National Health Insurance Service database 2017-2019. The participants were divided into two groups (SERM + VitD vs SERMs). After exclusion and propensity score matching, 2,885 patients from each group were included in the analysis. Fracture incidence was compared between groups. Kaplan-Meier curves were used to compare mortality. Cox proportional hazards regression analysis was used to compare the risks of fracture occurrence and mortality between the groups. RESULTS: The incidence rate (138.6/10,000 vs. 192.4/10,000 person-years), and risk of osteoporotic fractures (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.61-0.97; p = 0.024) were lower in the SERM + VitD group than in the SERMs group. Analysis for specific fractures showed a lower hazard of hip fracture in the SERM + VitD group (HR, 0.25; 95% CI, 0.09-0.71; p = 0.009). No difference was observed between the groups regarding mortality. CONCLUSION: The risk of osteoporotic fractures, especially hip fractures, was lower in the SERM + VitD group than in the SERMs group. Therefore, the composite agent of SERMs and vitamin D can be considered as a viable option for postmenopausal women with a relatively low fracture risk.

Risk of cardiovascular disease associated with long-term use of non-steroidal anti-inflammatory drugs in ankylosing spondylitis.

OBJECTIVE: To examine the risk of cardiovascular disease associated with long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) in a large real-world ankylosing spondylitis (AS) cohort. METHODS: This nationwide population-based cohort study used data from the Korean National Health Insurance Database. Patients aged ≥18 years old who were newly diagnosed with AS without prior cardiovascular disease between January 2010 and December 2018 were included in this study. Controls without AS were randomly selected by age, sex, and index year. The primary outcome was cardiovascular disease, a composite outcome of ischemic heart disease, stroke, or congestive heart failure. Long-term use of NSAIDs was defined as use of NSAIDs for >365 cumulative defined daily doses. The association between long-term use of NSAIDs and incident cardiovascular disease was examined in both AS and non-AS populations. RESULTS: Among 19 775 patients with AS and 59 325 matched controls without AS, there were 1,663 and 4,308 incident cases of cardiovascular disease, showing an incidence of 16.9 and 13.8 per 1,000 person-years, respectively. Long-term use of NSAIDs was associated with increased risk of cardiovascular disease in non-AS controls (adjusted hazard ratio [aHR], 1.64; 95% CI, 1.48-1.82). In contrast, long-term use of NSAIDs did not increase the risk of cardiovascular disease in AS patients (aHR, 1.06; 95% CI, 0.94-1.20; adjusted for age, sex, socioeconomic status, body mass index, smoking status, hypertension, diabetes, hyperlipidemia, and tumor necrosis factor inhibitor use). CONCLUSION: Prolonged NSAID treatment in AS patients may not be as harmful as in the general population regarding cardiovascular risk.

Risk of epilepsy in gonadal teratoma: a nationwide population-based study.

Epilepsy is a common neurological disease. Systemic tumors are associated with an increased risk of epileptic events. Paraneoplastic encephalitis related to gonadal teratoma is frequently accompanied by seizures and life-threatening status epilepticus (SE). However, the risk of epilepsy in gonadal teratoma has not been studied. This study aims to investigate the relationship between epileptic events and gonadal teratoma. This retrospective cohort study used the Korean National Health Insurance (KNHI) database. The study population was divided into two study arms (ovarian teratoma vs. control and testicular teratoma vs. control) with 1:2 age and gender-matched control groups without a history of gonadal teratoma or other malignancy. Participants with other malignancies, neurologic disorders, and metastatic brain lesions were excluded. We observed the occurrence of epileptic events during the observation period (2013-2018) and investigated the risk of epileptic events in each gonadal teratoma group compared to controls. In addition, the influence of malignancy and tumor removal was investigated. The final analysis included 94,203 women with ovarian teratoma, 2314 men with testicular teratoma, and controls. Ovarian teratoma is associated with a higher risk of epilepsy without SE (HR, 1.244; 95% CI 1.112-1.391) and epilepsy with SE (HR, 2.012; 95% CI 1.220-3.318) compared to the control group. The risk of epilepsy without SE was higher in malignant ovarian teratoma (HR, 1.661; 95% CI 1.358-2.033) than in benign (HR, 1.172; 95% CI 1.037-1.324). Testicular teratoma did not show significant relations with epileptic events. The risk of epileptic events showed a tendency to decrease after removing the ovarian teratoma. This study found that ovarian teratoma is associated with a higher risk of epileptic events, especially in malignant tumors, whereas testicular teratoma did not show significant differences in epileptic events compared to the control group. This study adds to the current understanding of the association between gonadal teratoma and epileptic events.

Comparative analysis of mortality and progression to end-stage renal disease between surgically induced and medical chronic kidney disease: A study using the National Health Insurance customized database.

PURPOSE: We aimed to compare the mortality rate and the risk for progression to end-stage renal disease (ESRD) and cardiovascular disease (CVD) between patients who underwent surgery for localized renal cell carcinoma (RCC) and those with chronic kidney disease (CKD) without surgery by investigating the National Health Insurance Service. MATERIALS AND METHODS: The surgical group (CKD-S) included patients who underwent radical or partial nephrectomy for RCC from 2007 to 2009. Grades of surgical CKD were classified according to the estimated glomerular filtration rate (eGFR) measured at a health screening within 2 years after surgery. The nonsurgical group (CKD-M) was graded according to the eGFR in the 2009-2010 health screenings. We performed 1:5 propensity score matching for age, gender, diabetes, hypertension, Charlson comorbidity index, smoking, alcohol consumption, baseline eGFR, and body mass index. RESULTS: A total of 8,698 patients (CKD-S, n=1,521; CKD-M, n=7,177) were analyzed. The CKD-M group was at higher risk for progression to ESRD (hazard ratio [HR] 1.90, 95% confidence interval [CI] 1.04-3.44, p=0.036) and CVD (HR 1.17, 95% CI 1.06-1.29, p=0.002) than the CKD-S group. In the group of patients with grade 3 disease or higher, the CKD-M group was at significantly higher risk for progression to ESRD (HR 2.21, 95% CI 1.47-3.31, p<0.001), CVD (HR 1.32, 95% CI 1.20-1.45, p<0.001), and overall mortality (HR 1.50, 95% CI 1.21-1.86, p<0.001). CONCLUSIONS: The risk for progression to ESRD, CVD, or mortality in patients with CKD-S may be lower than in patients with CKD-M.

Longitudinal trends in direct costs and healthcare utilization ascribable to inflammatory bowel disease in the biologic era: a nationwide, population-based study.

BACKGROUND AND AIM: Biologic-era data regarding the direct cost and healthcare utilization of inflammatory bowel disease at the population level are limited, especially in Asia. Thus, we aimed to investigate the nationwide prevalence, direct cost, and healthcare utilization of inflammatory bowel disease in Korea in a recent 10-year period. METHODS: Using the Korean National Health Insurance claim data from 2008 to 2017, we investigated all prescription medications and their associated direct costs, hospitalizations, and outpatient visits. We also estimated the nationwide prevalence of inflammatory bowel disease using population census data. RESULTS: The estimated inflammatory bowel disease prevalence significantly increased from 108.8/100 000 in 2008 to 140.4/100 000 in 2017. The overall annual costs for inflammatory bowel disease and the healthcare cost per capita increased from $24.5 million (in US dollars) to $105.1 million and from $458.4 to $1456.6 million, respectively (both P < 0.001). Whereas the ratio of outpatient costs increased from 35.3% to 69.4%, that of outpatient days remained steady. The total annual medication cost and proportion rose from $13.3 million to $76.8 million and from 54.2% to 73.3%, respectively, mainly due to the increasing antitumor necrosis factor cost, from $1.5 million to $49.3 million (from 11.1% to 64.1% of the total annual drug cost and from 6.3% to 46.9% of the total annual cost). CONCLUSIONS: We observed increasing trends in the prevalence, direct costs, and healthcare utilization of inflammatory bowel disease in Korea in recent years. The attributable cost was mainly driven by rising expenditures on antitumor necrosis factor medications.

Oral anticoagulants and concurrent rifampin administration in tuberculosis patients with non-valvular atrial fibrillation.

BACKGROUND: Evidence and guidelines for Non-vitamin K antagonist oral anticoagulants (NOACs) use when prescribing concurrent rifampin for tuberculosis treatment in patients with non-valvular atrial fibrillation (NVAF) are limited. METHODS: Using the Korean National Health Insurance Service database from January 2009 to December 2018, we performed a population-based retrospective cohort study to assess the net adverse clinical events (NACE), a composite of ischemic stroke or systemic embolism and major bleeding, of NOACs compared with warfarin among NVAF patients taking concurrent rifampin administration for tuberculosis treatment. After a propensity matching score (PSM) analysis, Cox proportional hazards regression was performed in matched cohorts to investigate the clinical outcomes. RESULTS: Of the 735 consecutive patients selected, 465 (63.3%) received warfarin and 270 (36.7%) received NOACs. Among 254 pairs of patients after PSM, the crude incidence rate of NACE was 25.6 in NOAC group and 32.8 per 100 person-years in warfarin group. There was no significant difference between NOAC and warfarin use in NACE (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.48-1.14; P = 0.172). Major bleeding was the main driver of NACE, and NOAC use was associated with a statistically significantly lower risk of major bleeding than that with warfarin use (HR, 0.63; 95% CI, 0.40-1.00; P = 0.0499). CONCLUSIONS: In our population-based study, there was no statically significant difference in the occurrence of NACE between NOAC and warfarin use. NOAC use may be associated with a lower risk of major bleeding than that with warfarin use.

Gemcitabine-cisplatin versus MVAC chemotherapy for urothelial carcinoma: a nationwide cohort study.

This study assessed the trends in methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) and gemcitabine-cisplatin (GC) regimens in Korean patients with metastatic urothelial carcinoma (UC) and compared the side effects and overall survival (OS) rates of the two regimens using nationwide population-based data. The data of patients diagnosed with UC between 2004 and 2016 were collected using the National Health Insurance Service database. The overall treatment trends were assessed according to the chemotherapy regimens. The MVAC and GC groups were matched by propensity scores. Cox proportional hazard analysis and Kaplan-Meier analysis were performed to assess survival. Of 3108 patients with UC, 2,880 patients were treated with GC and 228 (7.3%) were treated with MVAC. The transfusion rate and volume were similar in both the groups, but the granulocyte colony-stimulating factor (G-CSF) usage rate and number were higher in the MVAC group than in the GC group. Both groups had similar OS. Multivariate analysis revealed that the chemotherapy regimen was not a significant factor for OS. Subgroup analysis revealed that a period of ≥ 3 months from diagnosis to systemic therapy enhanced the prognostic effects of the GC regimen. The GC regimen was widely used as the first-line chemotherapy in more than 90% of our study population with metastatic UC. The MVAC regimen showed similar OS to the GC regimen but needed greater use of G-CSF. The GC regimen could be a suitable treatment option for metastatic UC after ≥ 3 months from diagnosis.

The Impact of BMI Changes on the Incidence of Glomerular Hematuria in Korean Adults: A Retrospective Study Based on the NHIS-HEALS Cohort.

Obesity and recurrent hematuria are known risk factors for chronic kidney disease. However, there has been controversy on the association between obesity and glomerular hematuria. This study aimed to investigate the association between body mass index (BMI) and weight change and recurrent and persistent hematuria in glomerular disease using a large-scale, population-based Korean cohort. Data were collected from the National Health Insurance Service-National Health Screening Cohort. Cox proportional hazards regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for recurrent and persistent hematuria in glomerular disease according to the BMI group. Compared with the BMI 23-25 kg/m2 group, the HR (95% CI) for incident recurrent and persistent hematuria in glomerular disease was 0.921 (0.831-1.021) in the BMI <23 kg/m2 group, 0.915 (0.823-1.018) in the BMI 25-30 kg/m2 group, and 1.151 (0.907-1.462) in the BMI ≥30 kg/m2 group. Compared with the stable weight group, the HRs (95% CIs) for incident recurrent and persistent hematuria in glomerular disease were 1.364 (1.029-1.808) and 0.985 (0.733-1.325) in the significant weight loss and gain groups, respectively. Despite adjusting for confounders, this result remained significant. Baseline BMI was not associated with the risk of incident recurrent and persistent hematuria in glomerular disease. Weight loss greater than 10% was associated with the incidence of recurrent and persistent hematuria in glomerular disease. Therefore, maintaining an individual's weight could help prevent recurrent and persistent hematuria in glomerular disease in middle-aged and older Korean adults.

Incidence of Retinal Artery Occlusion and Related Mortality in Korea, 2005 to 2018.

Importance: It remains unclear whether comorbidities in patients with retinal artery occlusion (RAO), a rare retinal vascular disorder, differ by subtype and whether mortality is higher. Objective: To examine the nationwide incidence of clinically diagnosed, nonarteritic RAO, causes of death, and mortality rate in patients with RAO compared with that in the general population in Korea. Design, Setting, and Participants: This retrospective, population-based cohort study examined National Health Insurance Service claims data from 2002 to 2018. The population of South Korea was 49 705 663, according to the 2015 census. Data were analyzed from February 9, 2021, to July 30, 2022. Main Outcomes and Measures: The nationwide incidence of any RAO, including central RAO (CRAO; International Statistical Classification of Diseases and Related Health Problems, Tenth Revision [ICD-10] code, H34.1) and noncentral RAO (other RAO; ICD-10 code, H34.2) was estimated using National Health Insurance Service claims data from 2002 to 2018, with 2002 to 2004 as the washout period. Furthermore, the causes of death were evaluated and the standardized mortality ratio was estimated. The primary outcomes were the incidence of RAO per 100 000 person-years and the standardized mortality ratio (SMR). Results: A total of 51 326 patients with RAO were identified (28 857 [56.2%] men; mean [SD] age at index date: 63.6 [14.1] years). The nationwide incidence of any RAO was 7.38 (95% CI, 7.32-7.44) per 100 000 person-years. The incidence rate of noncentral RAO was 5.12 (95% CI, 5.07-5.18), more than twice that of CRAO (2.25 [95% CI, 2.22-2.29]). Mortality was higher in patients with any RAO than in the general population (SMR, 7.33 [95% CI, 7.15-7.50]). The SMR for CRAO (9.95 [95% CI, 9.61-10.29]) and for noncentral RAO (5.97 [95% CI, 5.78-6.16]) showed a tendency toward a gradual decrease with increasing age. The top 3 causes of death in patients with RAO were diseases of the circulatory system (28.8%), neoplasms (25.1%), and diseases of the respiratory system (10.2%). Conclusions and Relevance: This cohort study found that the incidence rate of noncentral RAO was higher than that of CRAO, whereas SMR was higher for CRAO than noncentral RAO. Patients with RAO show higher mortality than the general population, with circulatory system disease as the leading cause of death. These findings suggest that it is necessary to investigate the risk of cardiovascular or cerebrovascular disease in patients newly diagnosed with RAO.

The associations between changes in hepatic steatosis and heart failure and mortality: a nationwide cohort study.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a well-known risk factor for cardiovascular (CV) disease (CVD) and mortality. However, whether the progression or regression of NAFLD can increase or decrease the risk of heart failure (HF) and mortality has not been fully evaluated. We investigated the association between changes in hepatic steatosis and the risks of incident HF (iHF), hospitalization for HF (hHF), and mortality including CV- or liver-related mortality. METHODS: Using a database from the National Health Insurance Service in Korea from January 2009 to December 2012, we analyzed 240,301 individuals who underwent health check-ups at least twice in two years. Hepatic steatosis was assessed using the fatty liver index (FLI), with an FLI ≥ 60 considered to indicate the presence of hepatic steatosis. According to FLI changes, participants were divided into four groups. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards regression models. RESULTS: Persistent hepatic steatosis increased the risk of iHF, hHF, and mortality including CV- and liver-related mortality compared with the group that never had steatosis (all P < 0.05). Incident hepatic steatosis was associated with increased risk for iHF and mortality including CV- or liver-related mortality (all P < 0.05). Compared with persistent steatosis, regression of hepatic steatosis was associated with decreased risk for iHF, hHF, and liver-related mortality (iHF, HR [95% CI], 0.800 [0.691-0.925]; hHF, 0.645 [0.514-0.810]; liver-related mortality, 0.434 [0.223-0.846]). CONCLUSIONS: FLI changes were associated with increased or decreased risk of HF outcomes and mortality.

Neoadjuvant versus adjuvant chemotherapy in upper tract urothelial carcinoma: A nationwide cohort study.

PURPOSE: This study aimed to evaluate the trend of adjuvant chemotherapy (AC) and neoadjuvant chemotherapy (NAC) in patients who underwent radical nephroureterectomy with bladder cuff excision (NUx) for upper tract urothelial carcinoma (UTUC) to compare the perioperative outcomes and overall survival (OS) between AC and NAC using nationwide population-based data. MATERIALS AND METHODS: We collected data on patients diagnosed with UTUC and treated with NUx between 2004 and 2016 using the National Health Insurance Service database, and evaluated the overall treatment trends. The AC and NAC groups were propensity score-matched. Cox proportional hazard and Kaplan-Meier analyses were used to assess survival. RESULTS: Of the 8,705 enrolled patients, 6,627 underwent NUx only, 94 underwent NAC, and 1,984 underwent AC. The rate of NUx without perioperative chemotherapy increased from 70.8 to 78.2% (R2 = 0.632; p < 0.001). The rates of dialysis (p = 0.398), TUR-BT (p = 1.000), and radiotherapy (p = 0.497) after NUx were similar. In the Kaplan-Meier curve, the NAC and AC groups showed no significant difference (p = 0.480). In multivariate analysis, treatment with AC or NAC was not associated with OS (hazard ratio 0.83, 95% confidence interval 0.49-1.40, p = 0.477). CONCLUSION: The use of NUx without perioperative chemotherapy has tended to increase in South Korea. Dialysis, TUR-BT, and radiotherapy rates after NUx were similar between the NAC and AC groups. There was no significant difference in OS between the NAC and AC groups. Proper perioperative chemotherapy according to patient and tumor conditions should be determined by obtaining more evidence of UTUC.

Nationwide Trends of Gatekeeper to Invasive Coronary Angiography in Suspected Coronary Artery Disease.

BACKGROUND AND OBJECTIVES: Real-world trends in the utility and type of gatekeeping studies in invasive coronary angiography (ICA) requires further investigation. METHODS: We identified outpatients who underwent noninvasive cardiac tests or directly ICA for suspected coronary artery disease (CAD) from the nationwide Korea Health Insurance Review and Assessment Service-National Patient Sample database between 2012 and 2018. RESULTS: Among 71,401 patients, the percentage of patients who were evaluated for suspected CAD was 34.7% for treadmill test (TMT), 4.2% for single-photon emission computed tomography (SPECT), 24.2% for coronary computed tomography angiography (CCTA), 1.6% for multiple gatekeepers, and 32.3% for directly ICA without noninvasive studies. The proportion of CCTA as a gatekeeper showed linear increase, (18.6% in 2012 and 28.8% in 2018; p<0.001), while those of TMT, SPECT, and direct ICA have decreased (p<0.001, p=0.03, and p<0.001, respectively). The overall incidence of downstream ICA after gatekeeper was 13.8% (6,662/48,346), and SPECT showed higher ICA rate in pairwise comparison with TMT and CCTA (p<0.001). Patients who performed gatekeepers before ICA showed higher rate of subsequent PCI (34.7% vs. 32.3%; p<0.001) and CABG (3.5% vs. 1.0%; p<0.001), compared to those who directly underwent ICA, and CCTA was associated with higher revascularization rate after ICA in pairwise comparison with TMT and SPECT (p<0.001). CONCLUSIONS: Nationwide database demonstrated that CCTA is utilized increasingly as a gatekeeper for ICA and is associated with high revascularization rate after ICA in outpatients with suspected CAD.

The association between prostatitis and risk of prostate cancer: a National Health Insurance Database study.

PURPOSE: Inflammation is thought to affect the development of prostate cancer (PCa). By retrospectively investigating the database of the National Health Insurance Service, this study attempted to perform a relevant analysis of patients with prostatitis and PCa. METHODS: Participants were aged ≥ 50 years. Patients diagnosed with prostatitis between 2010 and 2013 and matched controls were followed up until 2019. We selected controls with matched propensity scores for age, diabetes, hypertension, and the Charlson comorbidity index. Multivariate Cox regression analysis was conducted to determine the hazard ratio (HR) and 95% confidence interval (CI) of the association between prostatitis and PCa. The HR for PCa according to the presence of prostatitis was classified as acute, chronic, or other prostatitis. RESULTS: A total of 746,176 patients from each group were analyzed. The incidence of PCa was significantly higher in the group with prostatitis (1.8% vs 0.6%, p < 0.001). The HR for PCa was significantly higher in patients with prostatitis (HR 2.99; 95% CI 2.89-3.09, p < 0.001). The HR for PCa was significantly higher in acute prostatitis than in chronic prostatitis (3.82; 95% CI 3.58-4.08; p < 0.001; HR 2.77; 95% CI 2.67-2.87, p < 0.001). The incidence of all-cause death in patients diagnosed PCa was significantly lower in prostatitis group (HR 0.58, 95% CI 0.53-0.63, p < 0.001). CONCLUSION: Prostatitis is associated with an increased incidence of PCa. Acute prostatitis is associated with higher risk of PCa than chronic prostatitis. Clinicians should inform patients with prostatitis that they may have an increased risk of diagnosing PCa, and follow-up is needed.

Analysis of treatment outcomes according to the cycles of adjuvant chemotherapy in gastric cancer: a retrospective nationwide cohort study.

BACKGROUND: One-year S-1 or six-month capecitabine/oxaliplatin (CAPOX) has been the standard adjuvant chemotherapy for gastric cancer (GC). We investigated outcomes according to the cycles of adjuvant chemotherapy, using data from the Korean Health Insurance and Assessment Service. METHODS: A total of 20,552 patients, including 13,614 patients who received S-1 and 6,938 patients who received CAPOX extracted from 558,442 patients were retrospectively analyzed. The five-year overall survival rate was evaluated according to the duration of adjuvant chemotherapy. RESULTS: The five-year overall survival rate gradually increased according to the increase in adjuvant chemotherapy cycles in both the S-1 (≤ 5 cycles: 48.4%, hazard ratio [HR] 4.06, 95% confidence interval [CI] 3.74-4.40, P < 0.0001; 5 < cycles ≤ 6: 55.4%, HR 3.08, 95% CI 2.65-3.57, P < 0.0001; 6 < cycles ≤ 7: 64.1%, HR 2.11, 95% CI 1.84-2.41, P < 0.0001; 7 < cycles < 8: 71.1%, HR 1.60, 95% CI 1.39-1.84, P < 0.0001; ≥ 8 cycles: 77.9%) and the CAPOX groups (≤ 4 cycles: 43.5%, HR 3.20, 95% CI 2.84-3.61, P < 0.0001; 5 cycles: 45.3%, HR 2.63, 95% CI 2.11-3.27, P < 0.0001; 6 cycles: 47.1%, HR 2.09, 95% CI 1.76-2.49, P < 0.0001; 7 cycles: 55.3%, HR 1.63, 95% CI 1.35-1.96, P < 0.0001; ≥ 8 cycles: 67.2%). CONCLUSIONS: Reducing the treatment cycles of adjuvant chemotherapy in GC with S-1 or CAPOX showed inferior survival outcomes. Completing the standard duration of adjuvant chemotherapy with S-1 or CAPOX would be strongly recommended.

Trends in Mortality from Hemorrhagic Stroke in Korea from 2012 to 2020.

PURPOSE: To analyze trends in mortality rates from hemorrhagic stroke (HS) according to HS subtypes, using nationwide data from January 2012 to December 2020. MATERIALS AND METHODS: We used data from the National Health Claims Database provided by the National Health Insurance Service for 2012-2020 using the International Classification of Disease. The age-adjusted mortality rates of HS, which included subarachnoid hemorrhage (SAH) and intracerebral hemorrhage (ICH), were calculated, and additional analyses were conducted according to age and sex. RESULTS: The age-adjusted mortality rates for HS, SAH, and ICH decreased substantially in both sexes between 2012 and 2020. During the study period, mortality rates for HS decreased from 8.87 deaths per 100,000 inhabitants to 6.27 deaths per 100,000 inhabitants. Regarding SAH, mortality rates decreased from 3.72 deaths per 100,000 inhabitants to 2.57 deaths per 100,000 inhabitants. Concerning ICH, mortality rates decreased from 6.91 deaths per 100,000 inhabitants to 4.75 deaths per 100,000 inhabitants. The average annual percentage change for HS, SAH, and ICH was -0.04, -0.04, and -0.05, respectively. Mortality rates from HS, SAH, and ICH in both sexes decreased from 2012 to 2020 in all age groups. CONCLUSION: In Korea, the age-adjusted mortality rate of HS, SAH, and ICH demonstrated a declining trend in both sexes and across all age groups. These results may aid in the design and improvement of preventive strategies.

Neoadjuvant versus adjuvant chemotherapy in bladder cancer: a nationwide cohort study.

PURPOSE: Radical cystectomy is the standard of care for muscle-invasive bladder cancer. However, the 5-year survival rate is only about 50%. Therefore, additional treatments are needed. We compared the perioperative outcomes, overall survival, and treatment trends in patients with bladder cancer who underwent radical cystectomy and either neoadjuvant or adjuvant chemotherapy using nationwide population-based data. MATERIALS AND METHODS: We collected the data of patients diagnosed with bladder cancer treated with radical cystectomy between 2004 and 2016 using the National Health Insurance Service database. We evaluated overall treatment trends. The neoadjuvant chemotherapy and adjuvant chemotherapy groups were matched by propensity score. Cox proportional hazard analysis and Kaplan-Meier analysis were used to assess survival. RESULTS: Of 6134 patients, 1379 underwent adjuvant chemotherapy and 389 underwent neoadjuvant chemotherapy. The utilization rate of neoadjuvant chemotherapy increased from 6.4 to 12.2% from 2004 to 2016 (p = 0.018). The administration rate and number of granulocyte colony-stimulating factor cycles were lower in the neoadjuvant chemotherapy group than in the adjuvant chemotherapy group (p < 0.001 and p = 0.027, respectively). After propensity score matching, the neoadjuvant chemotherapy group had significantly better overall survival than the adjuvant chemotherapy group (p = 0.004). In multivariate analysis, neoadjuvant chemotherapy was associated with better overall survival (hazard ratio 0.77, 95% confidence interval 0.65-0.92, p = 0.003). CONCLUSIONS: Neoadjuvant chemotherapy was associated with lower granulocyte colony-stimulating factor administration and better overall survival than adjuvant chemotherapy. Neoadjuvant chemotherapy should be considered for patients with bladder cancer who undergo radical cystectomy.