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.

Colorectal cancer epidemiology in Korea

Although colorectal cancer emerged as a major public health concern, its incidence as well as mortality are decreasing during recent years in Korea. Most important contributor for these reduction in disease burden is colorectal cancer screening. Besides screening, primary prevention through risk factor modification could reduce 10% to 54% of colorectal cancer incidence. These factors include limiting alcohol, processed and red meat consumption, and cigarette smoking, maintaining optimal weight, and engaging physical activities.

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.

Colorectal cancer epidemiology in Korea

Although colorectal cancer emerged as a major public health concern, its incidence as well as mortality are decreasing during recent years in Korea. Most important contributor for these reduction in disease burden is colorectal cancer screening. Besides screening, primary prevention through risk factor modification could reduce 10% to 54% of colorectal cancer incidence. These factors include limiting alcohol, processed and red meat consumption, and cigarette smoking, maintaining optimal weight, and engaging physical activities.

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.