Beyond Acute COVID-19: Investigating the Incidence of Subacute Thyroiditis in Long COVID-19 in Korea.

BACKGRUOUND: The correlation between acute coronavirus disease 2019 (COVID-19) and subacute thyroiditis (SAT) has not been clearly investigated in "long COVID" patients. We aimed to investigate the incidence of SAT during convalescence and after the acute phase of COVID-19, comparing with that of the general population. METHODS: Data from a total of 422,779 COVID-19 patients and a control group of 2,113,895 individuals were analyzed. The index date was defined as the date 3 months after confirmation of COVID-19. The incidence rate (IR) of SAT and hazard ratios (HRs) were calculated per 100,000 persons. Subgroup analysis included analysis of HRs 90-179 and 180 days post-COVID-19 diagnosis; and additional analysis was conducted according to hospitalization status, sex, and age group. RESULTS: The IR of SAT was 17.28 per 100,000 persons (95% confidence interval [CI], 12.56 to 23.20) in the COVID-19 group and 8.63 (95% CI, 6.37 to 11.45) in the control group. The HR of COVID-19 patients was 1.76 (95% CI, 1.01 to 3.06; P=0.045). The HR of SAT was 1.39 (95% CI, 0.82 to 2.34; P=0.220) up to 6 months after the index date and 2.30 (95% CI, 1.60 to 3.30; P<0.001) beyond 6 months. The HR for SAT among COVID-19 patients was 2.00 (95% CI, 1.41 to 2.83) in hospitalized patients and 1.76 (95% CI, 1.01 to 3.06) in non-hospitalized patients compared to the control group. The IR of SAT was 27.09 (95% CI, 20.04 to 35.82) for females and 6.47 (95% CI, 3.34 to 11.30) for males. In the 19 to 64 age group, the IR of SAT was 18.19 (95% CI, 13.70 to 23.67), while the IR was 9.18 (95% CI, 7.72 to 10.84) in the 65 to 69 age group. CONCLUSION: SAT could be a potential long-term complication of COVID-19. Long-term surveillance for thyroid dysfunction is needed especially in hospitalized, female and young-aged subjects.

Risk of cancer in Korean patients with psoriatic arthritis: a nationwide population-based cohort study.

OBJECTIVE: While many studies on the increased risk of cancer in patients with psoriasis are available, data on the risk of cancer in patients with psoriatic arthritis (PsA) are still scarce. We assessed the risk of cancer in patients with PsA in a nationwide population-based cohort in Korea. METHODS: From 2010 to June 2021, patients newly diagnosed with PsA and 1:10 age-matched and sex-matched controls were included in this study. The outcome was the incidence of overall and specific cancers. RESULTS: Total 162 cancers occurred in 4688 PsA patients (incidence rate 83.2 (95% CI 70.8 to 97.0) per 10 000 person-years) and 1307 cancers occurred in 46 880 controls (incidence rate 66.9 (95% CI 63.3 to 70.6) per 10 000 person-years). The adjusted HR (aHR) of overall cancer in PsA patients was 1.20 (95% CI 1.02 to 1.41). However, this significance disappeared when non-melanoma skin cancer (NMSC) was excluded (aHR 1.16, 95% CI 0.98 to 1.37). Among specific cancers, the risk of NMSC (aHR 3.64 (95% CI 1.61 to 8.23)), lymphoma (aHR 2.63 (95% CI 1.30 to 5.30)) and thyroid cancer (aHR 1.83 (95% CI 1.18 to 2.85)) was higher in patients with PsA than in controls. CONCLUSION: The risk of overall cancer was higher in patients with PsA than in the general population. Patients with PsA had increased risks of NMSC, lymphoma and thyroid cancer compared with the general population. Our findings suggest a need to conduct cancer screening by a detailed history and comprehensive clinical examination in patients with PsA.

Risk of acute myocardial infarction, stroke, and venous thromboembolism among patients with anti-neutrophil cytoplasmic antibody-associated vasculitis in South Korea: A nationwide population-based study.

OBJECTIVES: To investigate the incidence and risk of cerebro-cardiovascular comorbidities (stroke, acute myocardial infarction, venous thromboembolism, and pulmonary embolism) in anti-neutrophil cytoplasmic antibody-associated vasculitis using nationwide Korean population-based medical claims data. METHODS: We identified 1905 patients with newly diagnosed anti-neutrophil cytoplasmic antibody-associated vasculitis during 2009-2019. Incidence rates and hazard ratios with 95% confidence intervals were calculated to estimate the risk of cerebro-cardiovascular comorbidities in these patients and compared to age- and sex-matched controls (1:10) using the Cox proportional hazards model. RESULTS: Most patients had microscopic polyangiitis (42.5%), followed by granulomatosis with polyangiitis (29.1%) and eosinophilic granulomatosis with polyangiitis (28.4%). The annual incidence rate of anti-neutrophil cytoplasmic antibody-associated vasculitis in 2019 was 0.55 per 100,000 person-years. Cerebro-cardiovascular comorbidities occurred in 12.6%. Stroke was most common (64.6%), followed by venous thromboembolism (34.6%), pulmonary embolism (18.3%), and acute myocardial infarction (5.4%). Korean patients with anti-neutrophil cytoplasmic antibody-associated vasculitis were at a significantly (2.3 times) higher overall risk for cerebro-cardiovascular comorbidities than the general population (adjusted hazard ratios, 4.5, 3.1, and 2.0 times higher for pulmonary embolism, venous thromboembolism, and stroke, respectively). These findings were similar for patients with each subtype of anti-neutrophil cytoplasmic antibody-associated vasculitis. CONCLUSIONS: This is the first nationwide population-based study to demonstrate a significant risk of cerebro-cardiovascular comorbidities as complications of anti-neutrophil cytoplasmic antibody-associated vasculitis in Korean patients. Knowing these risks may enable personalized patient care and improve overall survival.

Risk of Breast Cancer in Association with the Use of Second-generation Antipsychotics.

Objective: Previous studies regarding the relationship between the risk of breast cancer (BC) and antipsychotics use have reported inconsistent findings. Insufficient sample size and/or observation period may have hindered revealing the risk of BC associated with antipsychotics use. We aimed to investigate whether the use of second-generation antipsychotics (SGA) is associated with increased risk of BC. Methods: We used the Health Insurance Review Agency database in South Korea between 2008 and 2018. The index date was determined as the date of the first antipsychotic prescription. We selected women prescribed SGAs for more than 30 days within a year from the index date and age-matched controls, yielding 498,970 cases and 997,940 controls. The Cox proportional hazards regression model was used for estimating the risk. Results: The incidence rates of BC were 109.74 and 101.51 per 100,000 person-years in the case and control groups, respectively. There was an increased risk of BC in the case group (hazard ratio [HR] = 1.08, 95% confidence interval [CI] 1.04-1.13). There was a higher risk of BC in subjects prescribed with ≥ 10,000 mg of olanzapine equivalent dose (HR = 1.29, 95% CI 1.14-1.46) than those with < 10,000 mg (HR = 1.05, 95% CI 1.00-1.11). The increased risk of BC in the case group became significant after six years of the observation period (≥ 6 years: HR = 1.24, 95% CI 1.14-1.35, 3 to < 6 years: HR = 1.06, 95% CI 0.97-1.15, < 3 years: HR = 1.02, 95% CI 0.95-1.09). Conclusion: This study indicated that the use of SGAs is associated with increased risk of BC in a long-term relationship with a dose-response pattern.

The Comparative Risk of Serious Adverse Events With Tofacitinib and TNF Inhibitors in Patients With Ulcerative Colitis: The Korean Experience as Revealed by a National Database.

Tofacitinib is an oral, small-molecule Janus kinase inhibitor approved in South Korea for the treatment of moderate to severe ulcerative colitis (UC) on May 1, 2019. However, safety data are lacking. We investigated the incidence of serious adverse events (SAEs) in patients with UC using tofacitinib from the National Health Insurance Service database. In all, 1,026 UC patients were enrolled in this study. The overall incidences (100 person-years; 95% confidence interval) of SAEs were 4.06 (1.63-8.36) and 6.30 (4.59-8.43) in the tofacitinib and anti-TNFi groups, respectively. No thromboembolic event occurred and major cardiovascular events occurred in only three patients (two unstable angina and one congestive heart failure) in the tofacitinib group. The incidence of herpes zoster and tuberculosis did not differ between the two groups. There was no difference in the overall incidence of SAEs, including thromboembolic events, between tofacitinib- and TNFi-treated UC patients.

Clinical Effect of Hepatitis B Virus on COVID-19 Infected Patients: A Nationwide Population-Based Study Using the Health Insurance Review & Assessment Service Database.

BACKGROUND: Several studies have recently suggested that liver disease and cirrhosis were risk factors for poor outcomes in patients with coronavirus disease 2019 (COVID-19) infections. However, no large data study has reported the clinical course of COVID-19 patients with chronic hepatitis B virus (HBV) infections. This study investigated whether HBV infection had negative impacts on the clinical outcomes of COVID-19 patients. METHODS: We performed a nationwide population-based cohort study with 19,160 COVID-19-infected patients in 2020 from the Korean Health Insurance Review and Assessment database. The clinical outcomes of COVID-19 patients with chronic HBV infections were assessed and compared to those of non-HBV-infected patients. RESULTS: Of the 19,160 patients diagnosed with COVID-19, 675 (3.5%) patients had chronic HBV infections. The HBV-infected patients were older and had more commodities than the non-HBV infected COVID-19 patients. During the observation period, COVID-19-related mortality was seen in 1,524 (8.2%) of the non-HBV-infected 18,485 patients, whereas 91 (13.5%) in HBV-infected 675 patients died of COVID-19 infection. Compared to patients without HBV infections, a higher proportion of patients with chronic HBV infections required intensive care unit (ICU) admission and had organ failures. However, odds ratios for mortality, ICU admission, and organ failure were comparable between the two groups after adjusting for age, sex, and comorbid diseases including liver cirrhosis and hepatocellular carcinoma. CONCLUSION: COVID-19-infected patients with HBV infections showed worse clinical courses than non-HBV-infected COVID-19 patients. However, after adjustment, chronic HBV infection itself does not seem to affect the clinical outcomes in COVID-19 patients.

Entecavir versus Tenofovir for the Prevention of Hepatocellular Carcinoma in Treatment-naïve Chronic Hepatitis B Patients in Korea.

BACKGROUND: The occurrence of hepatocellular carcinoma (HCC) is a major concern during antiviral therapy for chronic hepatitis B. There are conflicting opinions regarding the effects of entecavir (ETV) and tenofovir disoproxil fumarate (TDF) on HCC prevention. We assessed these two antiviral medications for preventing HCC in treatment-naïve patients with chronic hepatitis B. METHODS: We conducted a retrospective cohort study using nationwide claims data from the Korea Health Insurance Review and Assessment Service. We included 55,473 treatment-naïve adult cases where ETV or TDF treatment was started between 2013 and 2017 (cohort 1). The ETV and TDF groups were matched 1:2 based on age, sex, comorbidities, hospital type, and index date year. Patients were followed up until December 2018. The outcome was the development of HCC. Subgroup analyses were conducted according to sex, age, hospital type and the presence of cirrhosis. We also compared the outcomes of patients who had started antiviral therapy during the 2012-2014 period (cohort 2). RESULTS: The matched participants (18,491 in the ETV and 36,982 in the TDF groups) were a part of the study for, on average, 41.2 months. The incidence of HCC did not differ significantly between the ETV (1.46 per 100 patient-years) and the TDF (1.36 per 100 patient-years) treatments (hazard ratio, 0.93; 95% confidence interval, 0.86-1.01; P = 0.081). By contrast, HCC incidence was significantly higher in the ETV group than tenofovir group of cohort 2. CONCLUSION: In patients with chronic hepatitis B, the ETV treatment did not result in a higher rate of HCC than the TDF treatment.

Radioactive Iodine Treatment for Children and Young Adults with Thyroid Cancer in South Korea: A Population-based Study.

PURPOSE: This study investigated radioactive iodine treatment (RAIT) patterns and the secondary cancer incidence among children and young adults receiving RAIT after thyroidectomy for thyroid cancer. METHODS: This population-based cohort study used the Health Insurance Review and Assessment database of South Korea to identify a total of 18 617 children and young adults (0-29 years) who underwent thyroidectomy for thyroid cancer between 2008 and 2018. We recorded age at surgery, sex, the interval from surgery to RAIT, the doses of RAI, the number of RAIT sessions, and secondary cancer incidence. RESULTS: A total of 9548 (51.3%) children and young adults underwent 1 or more RAIT sessions. The initial dose of RAIT was 4.35 ±â€…2.19 GBq. The overall RAIT frequency fell from 60.9% to 38.5%, and the frequency of high-dose RAIT (>3.7 GBq) fell from 64.2% to 36.5% during the observational period. A total of 124 cases of secondary cancer developed during 120 474 person-years of follow-up; 43 (0.5%) in the surgery cohort and 81 (0.8%) in the RAIT cohort. Thus, the RAIT cohort was at an increased risk of secondary cancer (adjusted hazard ratio 1.52 [95% confidence interval 1.03-2.24], P = 0.035). CONCLUSION: The proportion of children and young adults receiving RAIT, and the RAI dose, fell significantly over the observational period. RAIT was associated with secondary cancers. This is of major concern in the context of child and young adult thyroid cancer survivors.

Risk of Cancer Following the Use of N-Nitrosodimethylamine (NDMA) Contaminated Ranitidine Products: A Nationwide Cohort Study in South Korea.

N-nitrosodimethylamine (NDMA), a known carcinogenic agent, was recently detected in some products of ranitidine. Several studies have investigated the detectability of NDMA, in drugs and their risks. However, only a few epidemiological studies have evaluated cancer risk from the use of such individual drugs. This study investigates the risk of cancer in ranitidine users. We conducted an observational population-based cohort study using the Health Insurance Review and Assessment databases, which contain information about the use of medicines in South Korea. The primary study cohort consisted of ranitidine users (n = 88,416). For controls, we enrolled users of famotidine, another H2-receptor antagonist in which no NDMA has been detected. A 4:1 matched cohort was constructed to compare cancer outcomes of the two groups. Our matched cohort comprised of 40,488 ranitidine users and 10,122 famotidine users. There was no statistical difference in the overall cancer risk between the ranitidine and famotidine groups (7.45% vs. 7.56%, HR 0.99, 95% CI 0.91-1.07, p = 0.716). Additionally, no significant differences were observed in the analysis of 11 single cancer outcomes. We found no evidence that exposure to NDMA through ranitidine increases the risk of cancer.

Risk of non-Hodgkin's lymphoma and thyroid cancer in primary Sjögren's syndrome measured using the Korean Health Insurance Claims Database.

OBJECTIVES: The aim of this study was to evaluate the incidence and risk of non-Hodgkin's lymphoma (NHL) and thyroid cancer in patients with primary Sjögren's syndrome (pSS) using the Korean National Health Insurance Service (NHIS) claims database. METHODS: pSS was identified using the Korean NHIS medical claims database between 2007 and 2017. The case definition required more than one visit based on the SS diagnostic code and the registration system for rare and incurable diseases. We included all admissions with a primary diagnosis of lymphoma and thyroid cancer. RESULTS: The pSS incidence was 1.88 cases/100,000 inhabitants. Female patients had a higher incidence than male patients, with a female-to-male ratio of 7.65:1. Of those, we identified 18 (0.34%), 1 (0.02%) and 29 (0.56%) patients with NHL, Hodgkin's disease and thyroid cancer, respectively. For pSS, the standardised incidence ratios for NHL and thyroid cancer were 6.32 (95% confidence interval [CI] 4.09-9.38) and 1.23 (95% CI 0.88-1.68), respectively. Compared with the general population, female patients with pSS had a 6.95-fold higher risk of developing NHL, while the male patients did not. Patients with pSS did not have a higher risk of developing thyroid cancer. CONCLUSIONS: Although pSS is associated with a higher risk of developing NHL, the risk of NHL appears to have decreased compared with that in previous studies. Our study suggests that the risk of NHL or thyroid cancer with SS is not higher than that reported in previous studies.

Risk for Acromegaly-related Comorbidities by Sex in Korean Acromegaly.

CONTEXT: Reports on the incidence, characteristics, and comorbidity in Asian patients with acromegaly are scarce. OBJECTIVE: To evaluate the incidence of acromegaly and the risk of comorbidities in East Asia, especially South Korea. DESIGN: This nationwide population-based cohort study using the Korean Health Insurance Review and Assessment claims database evaluated the incidence of acromegaly, initially diagnosed from 2010 to 2013. We identified comorbidities during, before, and 2 years after diagnosis. Acromegaly and control cases (718 and 7180, respectively) were included in the analysis. SETTING: A longitudinal case-control study using a nationwide population cohort. RESULTS: The mean annual incidence rate of acromegaly was 3.57 cases per 1 000 000. Malignancies occurred in 61 patients with acromegaly (8.5%) during the study period and thyroid cancer was the most common malignancy (n = 38). In the acromegaly group, the overall risk of malignancy was higher: hazard ratio (HR), 2.82 (95% confidence interval [CI]: 2.12-3.74). Malignancy risk was more pronounced in females, with increased risk from the prediagnosis period that is sustained until the postdiagnosis period. Prevalence of diabetes mellitus (DM) and heart failure increased significantly in acromegalic patients. Over the entire period, DM developed in 51.1% and 57.0% of male and female acromegalic patients, respectively. Mortality risk was higher (HR 1.65, 95%; CI: 1.13-2.41) and statistically significant in females (HR 1.75, 95%; CI: 1.07-2.84). CONCLUSION: Comorbidities associated with acromegaly differed by sex in Korean subjects. High malignancy and mortality risk should be considered in female patients when managing acromegaly in Korea.

Association Between Pregnancy Outcomes and Radioactive Iodine Treatment After Thyroidectomy Among Women With Thyroid Cancer.

Importance: Current guidelines recommend that women delay pregnancy for 6 to 12 months after the receipt of radioactive iodine treatment (RAIT) following thyroidectomy for differentiated thyroid carcinoma. Although concerns exist regarding the risks associated with pregnancy after RAIT, no large-scale study, to date, has investigated the association between RAIT and pregnancy outcomes. Objective: To investigate whether RAIT was associated with increases in adverse pregnancy outcomes among South Korean women who received RAIT after thyroidectomy for thyroid cancer and to evaluate the appropriate interval between RAIT and conception. Design, Setting, and Participants: This population-based cohort study used the Health Insurance Review and Assessment database of South Korea to identify a total of 111 459 women of childbearing age (20-49 years) who underwent thyroidectomy for the treatment of differentiated thyroid carcinoma between January 1, 2008, and December 31, 2015. Participants were allocated to 2 cohorts: those who underwent surgery alone (n = 59 483 [53.4%]) and those who underwent surgery followed by RAIT (n = 51 976 [46.6%]). The pregnancy outcomes data were collected from January 1, 2008, to December 31, 2017. Main Outcomes and Measures: The rates of abortion (both spontaneous and induced), preterm delivery, and congenital malformation were assessed. Multivariate logistic regression models were used to control for confounding variables. Results: Among the 111 459 women of childbearing age who underwent thyroidectomy with or without RAIT for the treatment of thyroid cancer, the mean (SD) age at surgery or RAIT was 39.8 (6.7) years. Of those, 10 842 women (9.7%) became pregnant, and the mean (SD) age at conception was 33.3 (4.4) years. The rates of abortion, preterm delivery, and congenital malformation among patients who underwent surgery alone compared with patients who underwent surgery followed by RAIT were 30.7% vs 32.1% for abortion, 12.8% vs 12.9% for preterm delivery, and 8.9% vs 9.0% for congenital malformation, respectively (P > .05). A subgroup analysis based on the interval between RAIT and conception indicated congenital malformation rates of 13.3% for the interval of 0 to 5 months, 7.9% for 6 to 11 months, 8.3% for 12 to 23 months, and 9.6% for 24 months or more. The adjusted odds ratio of congenital malformation was 1.74 (95% CI, 1.01-2.97; P = .04) in conceptions that occurred 0 to 5 months after RAIT compared with conceptions that occurred 12 to 23 months after RAIT. The abortion rates based on the interval between RAIT and conception were 60.6% for the interval of 0 to 5 months, 30.1% for 6 to 11 months, 27.4% for 12 to 23 months, and 31.9% for 24 months or more. Conclusions and Relevance: These large-scale real-world data indicate that receipt of RAIT before pregnancy does not appear to be associated with increases in adverse pregnancy outcomes when conception occurs 6 months or more after treatment.

Incidence, comorbidities, and treatment patterns of nontuberculous mycobacterial infection in South Korea.

Nontuberculous mycobacteria (NTM) are important pathogens in humans, and hospital-based studies have shown an increased incidence of NTM infection. However, little is known about the treatment pattern of NTM infection with respect to the number of cases per population in South Korea. This study evaluated the trends in the incidence of NTM infection, respiratory comorbidities, and treatment patterns in South Korea.National claims data from the Health Insurance Review and Assessment service database for the years 2009 to 2015 were reviewed, and codes related to NTM infection, respiratory comorbidities occurring from one year before NTM infection and associated treatments were identified.In total, 52,551 patients were included in the study and the average annual incidence per 100,000 person-years was 12.8. The annual incidence was found to have increased from 6.6 to 26.6 per 100,000 persons. Accompanied comorbidities were tuberculosis (33.7%), followed by bronchial asthma (33.2%), chronic obstructive pulmonary disease (25.6%), and lung cancer (5.8%). A total of 76.6% of patients did not receive any combination treatment within one year after the diagnosis of NTM infection. Macrolide-based treatment was administered to 18.8% of patients.A dramatic increase in the incidence of NTM infection was noted in the population of South Korea. Approximately three-fourth of the patients with NTM infection were clinically observed without treatment for at least 1 year after the identification of NTM infection and most patients who treated NTM infection received macrolide-based combination therapy.

Incidence and Prevalence of Central Precocious Puberty in Korea: An Epidemiologic Study Based on a National Database.

OBJECTIVES: To investigate the prevalence and incidence of central precocious puberty in Korea using claims data provided by the Health Insurance Review and Assessment Service in Korea as the population-based epidemiologic study. STUDY DESIGN: In this national registry-based, longitudinal, epidemiologic study, patients who were registered with an International Classifications of Diseases, Tenth Revision diagnosis of central precocious puberty (E22.8 according to International Classifications of Diseases, Tenth Revision) and treated with gonadotropin-releasing hormone agonist were included. We assessed the age- and sex-specific prevalence and incidence rates of central precocious puberty in Korea from 2008 to 2014. RESULTS: A total of 37 890 girls and 1220 boys were newly registered with a diagnosis of central precocious puberty from 2008 to 2014. The overall incidence of central precocious puberty during the study period was 122.8 per 100 000 persons (girls, 262.8; boys, 7.0). The overall prevalence of central precocious puberty during the study period was 193.2 per 100 000 persons (girls, 410.6; boys, 10.9). The incidence and prevalence of central precocious puberty steeply increased during the study period in both girls and boys. CONCLUSIONS: This epidemiologic study, based on a national registry that included Korean children, demonstrated that the incidence and prevalence rates of central precocious puberty were high and increased steeply during the study period. Further investigations to determine the underlying causes for this rapid increase in central precocious puberty are needed.

Chemopreventive Effect of Rebamipide against Gastric Cancer in Patients who undergo Endoscopic Resection for Early Gastric Neoplasms: A Nationwide Claims Study.

BACKGROUND/AIMS: Previous studies have shown that rebamipide is potentially protective against gastric cancer; however, no epidemiologic studies of its chemopreventive effects in patients who have a high risk of gastric cancer have been performed. The aim of this study was to investigate whether rebamipide administration reduces the risk of gastric cancer. METHODS: We conducted a population-based cohort study using data retrospectively collected from the Health Insurance Review and Assessment Service database in Korea. Patients who underwent endoscopic submucosal dissection (ESD) for early gastric neoplasms between 2011 and 2014 were included. RESULTS: During 73,416 person-years of follow-up, 711 patients were newly diagnosed with gastric cancer, including 377 low-dose (below median) and 334 high-dose (above median) rebamipide users (37,157.4 and 36,258.3 per 100,000 person-years, respectively; log-rank test, p = 0.052). There were significant differences in gastric cancer incidence rates according to age, sex, and initial diagnosis at the time of index ESD. After adjusting for these clinical factors, high-dose use was associated with a reduced risk of gastric cancer (hazard ratio 0.858; 95% CI 0.739-0.995, p = 0.043). CONCLUSION: High-dose rebamipide is associated with reduced gastric cancer risk in high-risk populations who undergo endoscopic resection for early gastric neoplasms.

Real-world treatment patterns for patients 80 years and older with early lung cancer: a nationwide claims study.

BACKGROUND: Old age is an important factor that could affect the treatment of early-stage lung cancer. In this study, we evaluated the treatment patterns and outcomes of patients over the age of 80 years who had been diagnosed with early-stage lung cancer in real-world practice. METHODS: Elderly patients who were diagnosed with early-stage lung cancer between 2008 and 2016 were identified using claims data provided by the Health Insurance Review and Assessment Service. The proportion of patients who underwent surgical resection or stereotactic body radiation therapy (SBRT), practice pattern trends, and overall survival (OS) were analyzed from the population-based data. RESULTS: Over 9 years, 1,684 patients underwent surgical resection (74.9%) or SBRT (25.1%) as a localized treatment. From 2008 to 2016, the treatment modality changed: the percentage of patients who underwent surgical resection decreased from 90.6 to 71.4%, and those who underwent SBRT increased from 9.4 to 28.6%. The percentage of patients treated with SBRT increased over time (p < 0.001). The median OS was 56.4 months in the surgery group and 35.5 months in the SBRT group. The SBRT group showed worse OS compared with the surgery group (Adjusted hazard ratio, 1.44; 95% confidence interval, 1.21-1.72; p < 0.001). CONCLUSION: Changes in local treatment patterns in elderly lung cancer patients were observed and SBRT increased its role in this population. Surgical resection or SBRT should be considered the treatment of choice in elderly patients with localized lung cancer. Further prospective studies are required to elucidate the benefits of surgery and SBRT.

Incidence of gallstones after gastric resection for gastric cancer: a nationwide claims-based study.

PURPOSE: Gallstone formation is one of the most common problems after gastrectomy. This retrospective cohort study used the South Korean nationwide claims database to evaluate the incidence and risk factors of gallstone after gastrectomy for gastric cancer. METHODS: All consecutive patients who underwent gastrectomy for gastric cancer in South Korea in 2008-2010 were identified. Incidence of gallstone formation 5 years after gastrectomy in males and females, in various age groups, and after different types of gastrectomy was determined. Multivariate logistic regression analysis served to identify gallstone risk factors. RESULTS: Of the 47,752 patients, 2,506 (5.2%) developed gallstone during the 5-year follow-up period. At 12, 24, 36, and 48 months, the cumulative incidences were 1.2%, 2.2%, 3.3%, and 4.3%, respectively. Males had a higher incidence than females (5.8% vs. 4.1%, P < 0.001). Older patients (60-89 years) had a higher incidence than younger patients (30-59 years) (6.1% vs. 4.3%, P < 0.001). Gallstone was most common after total gastrectomy (6.6%), followed by proximal gastrectomy (5.4%), distal gastrectomy (4.8%), and pylorus-preserving distal gastrectomy (4.0%) (P < 0.001). Multivariate analysis showed that male sex (odds ratio [OR], 1.39), an older age (OR, 1.44), and total gastrectomy (OR, 1.40 vs. distal gastrectomy) were significant independent risk factors for postgastrectomy gallstone. CONCLUSION: The cumulative incidence of gallstone 5 years after gastrectomy for gastric cancer was 5.2%. Male sex, an older age, and total gastrectomy were significant risk factors. More careful monitoring for gallstone may be necessary in patients with such risk factors.

Osteoporosis and fracture after gastrectomy for stomach cancer: A nationwide claims study.

This study was planned to evaluate the incidence and risk factors of osteoporosis and fracture after gastrectomy for stomach cancer using a nationwide claims database in South Korea.Data from 41,512 patients (50-79 years) who underwent gastrectomy for stomach cancer from 2008 to 2010 with at least 5 years of follow-up were obtained from the Health Insurance Review and Assessment Service database. Patients diagnosed with osteoporosis and prescribed bisphosphonate or raloxifene or who experienced osteoporotic fractures after gastrectomy were operationally defined as osteoporosis. Osteoporotic fracture was defined as a fracture at common osteoporotic fracture sites (spine, pelvis, hip, forearm, or rib).In total, 37,076 patients were included in the final analysis. The incidences of postgastrectomy osteoporosis and osteoporotic fractures were 41.9 and 27.6 cases per 1000 person-years, respectively. Multivariate analysis showed that older age (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.79-1.96), female gender (HR 2.46; 2.35-2.58), total gastrectomy (HR 1.10; 1.04-1.16), and diabetes (HR 1.16; 1.11-1.22) were significantly associated with osteoporosis and that older age (HR 1.90; 95% CI 1.80-2.01), female gender (HR 1.50; 1.41-1.58), total gastrectomy (HR 1.17; 1.10-1.25), chemotherapy (HR 1.06; 1.00-1.12), and diabetes (HR 1.26; 1.19-1.33) were significantly associated with fractures. Osteoporotic fractures occurred a median 3.1 years after gastrectomy. Among the 5175 fracture patients, 780 (15.1%) experienced multisite fractures, mostly in the elderly and chemotherapy groups.The osteoporosis and osteoporotic fracture incidences are high in patients within a relatively short timeframe after gastrectomy for stomach cancer. Systematic management of osteoporosis is necessary after this surgery.

Incidence of Adhesive Bowel Obstruction After Colon Cancer Surgery and its Risk Factors: A Nationwide Claim Study.

OBJECTIVE: To elucidate the incidence of adhesive postoperative bowel obstruction (PBO) after colon cancer surgery and its risk factors using nationwide claim data. BACKGROUND: PBO has a significant impact on quality of life and medical costs after colectomy, though most of the literature consists of single-institution analyses. METHODS: Data from 24,645 patients who underwent regional colectomy for colon cancer from 2010 to 2012 and had at least 3 years of follow up were obtained from the Health Insurance Review and Assessment Service database. Patients who required nasogastric tube insertion or bowel obstruction surgery more than 30 days after index colectomy were defined as having PBO. RESULTS: A total of 3083 (12.5%) patients experienced at least one PBO episode within 3 years after surgery. Logistic regression analysis showed that significant risk factors for PBO were elderly (odds ratio, OR = 1.13), male (OR = 1.27), open colectomy (OR = 1.99), and low-volume institution (OR = 1.17). Among 3083 PBO patients, 50.7% experienced their 1st PBO during the 1st year after the index colectomy, and 7.8% experienced recurrence within 3 years after index colectomy. The 3-year cumulative incidences of PBO according to risk factors of elderly, male, open colectomy, and low-volume institution were 14.6%, 14.3%, 19.5%, and 15.1%, respectively. CONCLUSIONS: We report several independent risk factors for PBO and its incidence after regional colectomy for colon cancer. These results are informative for medical providers as patients who will or have had the procedure and could be useful baseline data for further research on the active prevention or treatment of PBO after colectomy.

Incidence of Clinically Relevant Incisional Hernia After Colon Cancer Surgery and Its Risk Factors: A Nationwide Claims Study.

BACKGROUND: As there is scant literature focusing on incisional hernia for which hospital care is sought, the aim of this study was to elucidate the incidence and risk factors of overt incisional hernia (OIH) after colon cancer surgery using nationwide claims data. METHODS: Claims data of colon cancer patients who underwent regional colectomy were obtained from the Health Insurance Review and Assessment Service database of South Korea. Data from 2010 to 2012 were collected to ensure adequate follow-up. OIH was considered to be present when either the diagnosis code for IH or the claim code for IH repair was entered after index colectomy for colon cancer. RESULTS: A total of 24,645 patients underwent regional colectomy for colon cancer during the study period. Of these, 376 (1.5%) patients had an OIH within 3 years after surgery, and 50.3% of OIHs developed within the first year after the index colectomy (883.7 cases/10,000 patient-years). The Cox proportional hazard model showed that age >65 years, female gender, open colectomy, and institution volume <100 colectomies per year were statistically significant risk factors for OIH. The 3-year cumulative OIH incidence rates according to age >65 years, female gender, open colectomy, and institution volume <100 colectomies per year were 2.1, 2.1, 2.0, and 2.1%, respectively. CONCLUSIONS: Several risk factors for OIH and its incidence after regional colectomy for colon cancer were identified. These findings are helpful for classifying patients undergoing segmental colectomy who have increased the likelihood of developing IH and are informative for patients and medical providers performing the surgery.