Background: The infant mortality rate (IMR) has been considered an important indicator of the overall public health level. Despite improvements in recent decades, regional inequalities in the IMR have been reported worldwide. However, there are no Korean epidemiological studies on regional disparities in the IMR. Methods: We extracted causes of death data from the Statistics Korea through the Korean Statistical Information Service database between 2001 and 2021. The total and regional IMRs were calculated to determine regional disparities. Based on causes of death and using Seoul as a reference, the excess infant deaths and population attributable fractions (PAFs) were calculated for 15 other metropolitan cities and provinces. The average annual percent changes by region from 2001 to 2021 were obtained using a joinpoint regression program. To assess inequities in IMR trends, the rate ratios (RRs) and rate differences (RDs) of the 15 regions were calculated by dividing the study period into period 1 (2001–2007), period 2 (2008–2014), and period 3 (2015–2021). Results: The overall IMR in Korea was 3.64 per 1,000 live births, and the IMRs in the 14 regions were relatively higher than that in Seoul, with RRs ranging from 1.15 (95% confidence interval [CI], 1.04, 1.27) in Jeju-do to 1.62 (95% CI, 1.54, 1.71) in Daegu, over the total study period. Significant differences in infant deaths by region were observed for all causes of death, with PAFs ranging from 2.2% (95% CI, 1.7, 2.6) in Gyeonggi-do to 38.4% (95% CI, 38.1, 38.6) in Daegu. The leading cause of excess infant deaths was perinatal problems. The IMR disparities in the relative and absolute measures decreased from 1.44 (1.34, 1.54) to 1.21 (1.10, 1.31) for RRs and from 0.79 (0.63, 0.96) to 0.30 (0.15, 0.45) for RDs between periods 1 and 2, followed by an increase from 1.21 (1.10, 1.31) to 1.36 (1.21, 1.53) for RRs and from 0.30 (0.15, 0.45) to 0.51(0.36, 0.67) for RDs between period 2 and 3. Conclusion Infant death is associated with place of residence and regional gaps have recently widened again in Korea. An in-depth investigation of the causes of regional disparities in infant mortality is required for effective governmental policies to achieve equality in infant health.

PURPOSE: The current study was undertaken to examine the trends in the lung cancer incidence, mortality, and survival after a diagnosis in Korea. MATERIALS AND METHODS: Lung cancer incidence data according to the histologic type and mortality data were obtained from the Korea Central Cancer Registry and the Statistics Korea, respectively. The age-standardized incidence and mortality rates were calculated, and the Joinpoint model and age-period-cohort analyses were used to describe the trends in the rates. The 5-year relative survival rates of lung cancer were also calculated. RESULTS: Although the number of new lung cancer cases increased between 1999 and 2012, the age-standardized incidence rate decreased by 0.9% per year in men, whereas the incidence in women increased by 1.7% per year over the same time. Until 2010, the most common histologic type in men was squamous cell carcinoma, then adenocarcinoma prevailed thereafter. Since 1999, the most frequent histological type in women was adenocarcinoma. The lung cancer mortality started to decrease in 2002, with a more apparent decline for the younger age groups in both men and women. Overall, the 5-year relative survival rates have improved significantly from 11.2% for men and 14.7% for women among patients diagnosed between 1993 and 1997 to 19.3% for men and 28.2% for women among patients diagnosed between 2008 and 2012, respectively. An improvement in survival rate was observed for all major histology groups. CONCLUSION: The epidemiology of lung cancer in Korea has changed over a short time span, with decreasing mortality and improving survival rates. Further study is warranted to determine the cause of these changes.
Adenocarcinoma ; Carcinoma, Squamous Cell ; Diagnosis ; Epidemiology* ; Female ; Humans ; Incidence ; Korea* ; Lung Neoplasms* ; Lung* ; Male ; Mortality ; Survival Rate

No abstract available.
Colorectal Neoplasms* ; Incidence* ; Korea*

No abstract available.
Colorectal Neoplasms* ; Incidence* ; Korea*

PURPOSE: The current study was undertaken to examine the trend in gallbladder cancer (GBC) incidenceand survival in Korea. MATERIALS AND METHODS: GBC incidence data by histologic typewere obtained from the Korea Central Cancer Registry.Age-standardized incidence rates were calculated using the mid-year Korean population of2000 as a standard population, and a joinpoint regression model was used to calculate theannual percent change (APC) in incidence rates. Incidence by Surveillance, Epidemiology and End Results (SEER) summary stage and by geographical areas and female-to-male incidencerate ratios was also described. RESULTS: The number of new GBC cases increased between 1999 and 2013. Nevertheless, the agestandardizedincidence rate decreased by 0.5% per year in men (p < 0.01), whereas theincidence rate in women did not change significantly over the same period (APC, –0.2;p=0.59). The most common histologic type was adenocarcinoma in both sexes. Based onthe SEER stage, the distant stage was the most frequent stage (41%), followed by theregional stage (37%). Ulsan (4.31/100,000 for men and 4.09/100,000 forwomen in 2009-2013) and Gyeongsangnam-do (4.15/100,000 for men and 3.54/100,000 for women)showed the highest GBC incidence, whereas the lowest incidence was observed in Seouland Gyeonggi-do. There were no significant sex differences in the incidence of GBC (femaleto-maleincidence rate ratio, 0.96). CONCLUSION: The overall incidence of GBC in Korea did not change significantly over the 15-year period.Incidence for men and women was similar. However, geographical variation was found.
Adenocarcinoma ; Epidemiology ; Female ; Gallbladder Neoplasms* ; Gallbladder* ; Gyeonggi-do ; Gyeongsangnam-do ; Humans ; Incidence* ; Korea* ; Male ; Sex Characteristics ; Ulsan

Purpose: This study aimed to examine secular trends, age-period-cohort effects, and geographical differences in gastric cancer (GC) mortality in Korea. Materials and Methods: Using cause of death data from the Korean Statistical Information Service for GC from 2000 to 2020, we calculated average annual percentage changes (AAPCs) in the age-standardized mortality of GC in 17 cities and provinces through joinpoint regression. Decomposition of age, period, and cohort effects on GC mortality were elucidated by applying a log-linear model and an intrinsic estimate method. Spatial patterns and the degree of spatial clustering in 250 administrative regions were explored via Moran’s I statistics. Stratification by sex was performed for all analyses. Results: The age-standardized mortality of GC per 100,000 persons declined from 29.0 in 2000 to 7.9 in 2020 (AAPC, -6.28%). Age-period-cohort analyses of GC mortality showed a downward trend among five-year age groups from age 20-89 years across five-year periods from 2005-2020 and five-year birth cohorts from 1920-2000. Overall, the younger birth cohort showed lower mortality rates than the older cohort within the same period. In 2020, clusters of high GC mortality were observed in the central area for men (Chungcheongbuk, Jeollabuk, Gyeongsangbuk, and Gyeongsangnam) and in the eastern area for women (Gyeongsangbuk). Conclusion This study identified a downward trend in GC mortality among men and women from 2000 to 2020 in Korea. This trend was mainly attributed to birth cohort rather than period effects. Spatial analysis showed high GC mortality in the Chungcheong and Gyeongsangbuk areas.

OBJECTIVES: Previous large-scale cohort studies conducted in Korea have found a positive association between diabetes mellitus (DM) and colorectal cancer (CRC) in men only, in contrast to studies of other populations that have found significant associations in both men and women. METHODS: A total of 1070 CRC cases and 2775 controls were recruited from the National Cancer Center, Korea between August 2010 and June 2013. Self-reported DM history and the duration of DM were compared between cases and controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by binary and polytomous logistic regression models. RESULTS: DM was associated with an elevated risk of CRC in both men (OR, 1.47; 95% CI, 1.13 to 1.90) and women (OR, 1.92; 95% CI, 1.24 to 2.98). This association remained when we controlled for age, body mass index, alcohol consumption, and physical activity level. In sub-site analyses, DM was associated with distal colon cancer risk in both men (multivariate OR, 2.04; 95% CI, 1.39 to 3.00) and women (multivariate ORs, 1.99; 95% CI, 1.05 to 3.79), while DM was only associated with rectal cancer risk in women (multivariate OR, 2.05; 95% CI, 1.10 to 3.82). No significant association was found between DM and proximal colon cancer risk in either men (multivariate OR, 1.45; 95% CI, 0.88 to 2.41) or women (multivariate OR, 1.79; 95% CI, 0.78 to 4.08). CONCLUSIONS: Overall, DM was associated with an increased risk of CRC in Koreans. However, potential over-estimation of the ORs should be considered due to potential biases from the case-control design.
Adult ; Aged ; Case-Control Studies ; Cohort Studies ; Colorectal Neoplasms/*etiology ; Diabetes Mellitus, Type 2/*complications ; Female ; Humans ; Logistic Models ; Male ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Republic of Korea ; Risk Factors