A Nationwide Cohort Study Shows a Sex-Dependent Change in the Trend of Peptic Ulcer Bleeding Incidence in Korea between 2006 and 2015

Background/Aims@#The incidence of peptic ulcer disease has decreased in past decades; however, the trends in peptic ulcer bleeding (PUB) are inconsistent among regions. This study aimed to investigate the trends in PUB incidence and the effect of risk factors on PUB in Korea. @*Methods@#The records of patients hospitalized with PUB from 2006 to 2015 were retrieved from the Korean National Health Insurance Service Database. Standardized incidences of PUB were calculated, and the clinical characteristics such as age, sex, Helicobacter pylori infection, drug exposure, comorbidities, and mortality were obtained. @*Results@#In total, 151,507 hospitalizations with PUB were identified. The overall annual hospitalization rate was 34.98 per 100,000 person-years. The incidence of PUB showed no significant change from 2006 to 2008 and decreased from 2008 to 2015, with an annual change of –2.7% (p<0.05); however, this change was only significant in men. The incidence of PUB was higher in men than in women between 40 and 70 years old and higher in women than in men older than 80 years. From 2006 to 2015, the H. pylori infection rate increased significantly in patients with PUB;however, there was no significant change in exposure to nonsteroidal anti-inflammatory drugs or other drugs that increase the risk of PUB. @*Conclusions@#Over the past decade, the incidence of PUB has decreased in a sex-specific manner. There has been a decreasing trend in the H. pylori infection rate and no change in exposure to drugs that increase the risk of PUB in Korea.

A Nationwide Cohort Study Shows a Sex-Dependent Change in the Trend of Peptic Ulcer Bleeding Incidence in Korea between 2006 and 2015

Background/Aims@#The incidence of peptic ulcer disease has decreased in past decades; however, the trends in peptic ulcer bleeding (PUB) are inconsistent among regions. This study aimed to investigate the trends in PUB incidence and the effect of risk factors on PUB in Korea. @*Methods@#The records of patients hospitalized with PUB from 2006 to 2015 were retrieved from the Korean National Health Insurance Service Database. Standardized incidences of PUB were calculated, and the clinical characteristics such as age, sex, Helicobacter pylori infection, drug exposure, comorbidities, and mortality were obtained. @*Results@#In total, 151,507 hospitalizations with PUB were identified. The overall annual hospitalization rate was 34.98 per 100,000 person-years. The incidence of PUB showed no significant change from 2006 to 2008 and decreased from 2008 to 2015, with an annual change of –2.7% (p<0.05); however, this change was only significant in men. The incidence of PUB was higher in men than in women between 40 and 70 years old and higher in women than in men older than 80 years. From 2006 to 2015, the H. pylori infection rate increased significantly in patients with PUB;however, there was no significant change in exposure to nonsteroidal anti-inflammatory drugs or other drugs that increase the risk of PUB. @*Conclusions@#Over the past decade, the incidence of PUB has decreased in a sex-specific manner. There has been a decreasing trend in the H. pylori infection rate and no change in exposure to drugs that increase the risk of PUB in Korea.

Gallstones, Cholecystectomy and the Risk of Hepatobiliary and Pancreatic Cancer: A Nationwide Population-based Cohort Study in Korea

Several epidemiological studies suggest a potential association between gallstones or cholecystectomy and hepatobiliary and pancreatic cancers (HBPCs). The aim of this study was to evaluate the risk of HBPCs in patients with gallstones or patients who underwent cholecystectomy in the Korean population. A retrospective cohort was constructed using the National Health Insurance Service-National Sample Cohort (NHIS-NSC). Gallstones and cholecystectomy were defined by diagnosis and procedure codes and treated as time-varying covariates. Hazard ratios (HRs) in relation to the risk of HBPCs were estimated by Cox proportional hazard models. Among the 704,437 individuals who were included in the final analysis, the gallstone prevalence was 2.4%, and 1.4% of individuals underwent cholecystectomy. Between 2002 and 2015, 487 and 189 individuals developed HBPCs in the gallstone and cholecystectomy groups, respectively. A significant association was observed between gallstones and all HBPCs (HR 2.16;95% CI 1.92-2.42) and cholecystectomy and all HBPCs (HR 2.03; 95% CI 1.72-2.39). However, when 1-, 3-, and 5-year lag periods were applied, the HBPC and subsites risk approached zero. A significant association was observed between cholecystectomy and intrahepatic bile duct cancer (IBDC) (HR 2.68; 95% CI 1.63-4.40). When 1-, 3- and 5-year lag periods were applied, the IBDC risk after cholecystectomy was 2.86-fold (95% CI 1.68-4.85), 2.92-fold (95% CI 1.51-5.64), and 4.08-fold (95% CI 1.94-8.61) higher, respectively, than that in the comparison group. In conclusion, gallstone diagnosis and cholecystectomy seem to correlate with HBPCs, especially cholecystectomy and IBDC.

Validity of Self-reported Stroke and Myocardial Infarction in Korea: The Health Examinees (HEXA) Study / 예방의학회지

OBJECTIVES@#Self-reported disease history is often used in epidemiological studies. In this study, we acquired the hospital records of subjects who self-reported stroke or myocardial infarction (MI) and evaluated the validity of the participants’ self-reported disease history. We also determined the level of agreement between specialists and non-specialists.@*METHODS@#Among the participants in the Health Examinees study, 1488 subjects self-reported stroke or MI during 2012-2017, and medical records were acquired for the 429 subjects (28.8%) who agreed to share their medical information. Each record was independently assigned to 2 medical doctors for review. The records were classified as ‘definite,’‘possible,’ or ‘not’ stroke or MI. If the doctors did not agree, a third doctor made the final decision. The positive predictive value (PPV) of self-reporting was calculated with the doctors’ review as the gold standard. Kappa statistics were used to compare the results between general doctors and neurologists or cardiologists.@*RESULTS@#Medical records from 208 patients with self-reported stroke and 221 patients with self-reported MI were reviewed. The PPV of self-reported disease history was 51.4% for stroke and 32.6% for MI. If cases classified as ‘possible’ were counted as positive diagnoses, the PPV was 59.1% for stroke and 33.5% for MI. Kappa statistics showed moderate levels of agreement between specialists and non-specialists for both stroke and MI.@*CONCLUSIONS@#The validity of self-reported disease was lower than expected, especially in those who reported having been diagnosed with MI. Proper consideration is needed when using these self-reported data in further studies.

The Risk of Colorectal Cancer After Cholecystectomy or Appendectomy: A Population-based Cohort Study in Korea / 예방의학회지

OBJECTIVES: We investigated the association between cholecystectomy or appendectomy and the subsequent risk of colorectal cancer (CRC) in the Korean population. METHODS: A retrospective cohort study was conducted with the National Health Insurance Service–National Sample Cohort of Korea; this sample was followed up from January 1, 2002, until the date of CRC incidence, loss to follow-up, or December 31, 2015. The exposure status of cholecystectomy and appendectomy was treated as a time-varying covariate. The calculated risk of CRC was stratified by follow-up period, and the association between these surgical procedures and CRC was investigated by a Cox regression model applying appropriate lag periods. RESULTS: A total of 707 663 individuals were identified for analysis. The study population was followed up for an average of 13.66 years, and 4324 CRC cases were identified. The hazard ratio (HR) of CRC was elevated in the first year after cholecystectomy (HR, 1.71; 95% confidence interval [CI], 1.01 to 2.89) and in the first year and 2-3 years after appendectomy (HR, 4.22; 95% CI, 2.87 to 6.20; HR, 2.34; 95% CI, 1.36 to 4.03, respectively). The HRs of CRC after applying 1 year of lag after cholecystectomy and 3 years of lag after appendectomy were 0.80 (95% CI, 0.57 to 1.13) and 0.77 (95% CI, 0.51 to 1.16), respectively. CONCLUSIONS: The risk of CRC increased in the first year after cholecystectomy and appendectomy, implying the possibility of bias. When appropriate lag periods after surgery were applied, no association was found between cholecystectomy or appendectomy and CRC.

Comparative Effects of Mattress Type on Subjective and Objective Sleep Quality: A Preliminary Study / 수면정신생리

OBJECTIVES: We aimed to evaluate the effects of mattress type on both objective and subjective sleep quality in healthy good sleepers. METHODS: Fifteen healthy good sleepers with a mean age of 30.8 years participated in this study. A randomized crossover trial was carried out using two different mattress types: a standard mattress and a contour coil mattress. After a night of adaptation, all participants were randomized to either a standard mattress or a contour coil mattress. Then, nocturnal polysomnography was conducted for two consecutive nights. Subjective evaluations were obtained using a self-report questionnaire before and after the polysomnographic recording sessions. RESULTS: The polysomnographic showed no differences in total sleep time, sleep stage, or wake time after sleep onset between the two mattress conditions. Of the polysomnographic variables, only sleep onset latency was significantly reduced for the contour coil mattress. Additionally, participants reported better subjective sleep quality when sleeping on the contour coil mattress, according to the questionnaires. CONCLUSION: The type of mattress might affect not only subjective, but also objective sleep quality, including sleep onset latency.