Investigating Factors Influencing the National Cancer Screening Program among Older Individuals in Republic of Korea-Data from the Korea National Health and Nutrition Examination Survey VIII

This study aims to determine the influencing factors of the participation of older individuals aged 65 years and above in South Korea's National Cancer Screening Program (NCSP) using data from the eighth wave (2019-2021) of the Korea National Health and Nutrition Examination Survey (KNHANES VIII), and discuss potential problems and coping strategies. Variables were selected based on Andersen's healthcare utilization model. "Participation in the NSCP" was considered the dependent variable, with independent variables including sociodemographic characteristics (sex, marital status, residence, education level, income level, economic activity, medical coverage type, and private insurance), health conditions (subjective health status, hypertension, and diabetes), and health behaviors (physical activity, monthly alcohol consumption, and current smoking status). The analysis revealed that higher participation rates correlated with being married, having an education level beyond elementary school, being employed, subscribing to private insurance, perceiving oneself as having average or poor health, engaging in physical activity, and not smoking. Sex, residence, income, medical coverage type, hypertension, diabetes, and monthly alcohol consumption were found to be insignificantly correlated. These findings underscore the importance of tailored promotion and health education for older individuals to boost NCSP participation rates, which could ultimately elevate public health standards.

Effect of physical activity on incident atrial fibrillation in individuals with varying duration of diabetes: a nationwide population study

BACKGROUND

Diabetes mellitus (DM) duration affects incident atrial fibrillation (AF) risk; the effect of physical activity on mitigating AF risk related to varying DM duration remains unknown. We assessed the effect of physical activity on incident AF in patients with DM with respect to known DM duration.

METHODS

Patients with type 2 DM who underwent the Korean National Health Insurance Service health examination in 2015-2016 were grouped by DM duration: new onset and < 5, 5-9, and ≥ 10 years. Physical activity was classified into four levels: 0, < 500, 500-999, 1,000-1,499, and ≥ 1,500 metabolic equivalent task (MET)-min/week, with the primary outcome being new-onset AF.

RESULTS

The study enrolled 2,392,486 patients (aged 59.3 ± 12.0 years, 39.8% female) with an average follow-up of 3.9 ± 0.8 years and mean DM duration of 5.3 ± 5.1 years. Greater physical activity was associated with a lower AF risk. Lowering of incident AF risk varied with different amounts of physical activity in relation to known DM duration. Among patients with new-onset DM, DM duration < 5 years and 5-9 years and 1,000-1,499 MET-min/week exhibited the lowest AF risk. Physical activity ≥ 1,500 MET-min/week was associated with the lowest incident AF risk in patients with DM duration ≥ 10 years (by 15%), followed DM duration of 5-9 years (12%) and < 5 years (9%) (p-for-interaction = 0.002).

CONCLUSIONS

Longer DM duration was associated with a high risk of incident AF, while increased physical activity generally reduced AF risk. Engaging in > 1,500 MET-min/week was associated with the greatest AF risk reduction in patients with longer DM duration, highlighting the potential benefits of higher activity levels for AF prevention.

Regional differences in health screening participation between before and during COVID-19 pandemic

BACKGROUND

Health screening is a preventive and cost-effective public health strategy for early detection of diseases. However, the COVID-19 pandemic has decreased health screening participation. The aim of this study was to examine regional differences in health screening participation between before and during COVID-19 pandemic and vulnerabilities of health screening participation in the regional context.

METHODS

Administrative data from 229 districts consisting of 16 provinces in South Korea and health screening participation rate of each district collected in 2019 and 2020 were included in the study. Data were then analyzed via descriptive statistics and geographically weighted regression (GWR).

RESULTS

This study revealed that health screening participation rates decreased in all districts during COVID-19. Regional vulnerabilities contributing to a further reduction in health screening participation rate included COVID-19 concerns, the population of those aged 65+ years and the disabled, lower education level, lower access to healthcare, and the prevalence of chronic disease. GWR analysis showed that different vulnerable factors had different degrees of influence on differences in health screening participation rate.

CONCLUSIONS

These findings could enhance our understanding of decreased health screening participation due to COVID-19 and suggest that regional vulnerabilities should be considered stringent public health strategies after COVID-19.

Prediction Model for Hypertension and Diabetes Mellitus Using Korean Public Health Examination Data (2002–2017)

Hypertension and diabetes mellitus are major chronic diseases that are important factors in the management of cardiovascular disease. In order to prevent the occurrence of chronic diseases, proper health management through periodic health check-ups is necessary. The purpose of this study is to determine the incidence of hypertension and diabetes mellitus according to the health check-up, and to develop a predictive model for hypertension and diabetes according to the health check-up. We used the National Health Insurance Corporation database of Korea and checked whether hypertension or diabetes occurred from that date according to the number of health check-ups over the past 10 years. Compared to those who underwent five health check-ups, those who participated in the first screening had hypertension (OR = 2.18, 95% CI = 2.14–2.22), diabetes mellitus (OR = 1.33, 95% CI = 1.30–1.35) and both diseases (OR = 2.46, 95% CI = 2.39–2.53); individuals who underwent 10 screenings had hypertension (OR = 0.86, 95% CI = 0.83–0.88), diabetes mellitus (OR = 0.83, 95% CI = 0.81–0.85) and both diseases (OR = 0.83, 95% CI = 0.79–0.87). Individuals who attended fewer than five screenings compared with individuals who attended five or more screenings had hypertension (OR = 1.61, 95% CI = 1.59–1.62; AUC = 0.66), diabetes mellitus (OR = 1.21, 95% CI = 1.20–1.22; AUC = 0.59) and both diseases (OR = 1.75, 95% CI = 1.72–1.78, AUC = 0.63). The machine learning-based prediction model using XGBoost showed higher performance in all datasets than the conventional logistic regression model in predicting hypertension (accuracy, 0.828 vs. 0.628; F1-score, 0.800 vs. 0.633; AUC, 828 vs. 0.630), diabetes mellitus (accuracy, 0.707 vs. 0.575; F1-score, 0.663 vs. 0.576; AUC, 0.710 vs. 0.575) and both diseases (accuracy, 0.950 vs. 0.612; F1-score, 0.950 vs. 0.614; AUC, 0.952 vs. 0.612). It was found that health check-up had a great influence on the occurrence of hypertension and diabetes, and screening frequency was more important than other factors in the variable importances.

Time delays and risk factors in the management of patients with active pulmonary tuberculosis: nationwide cohort study

Estimating the time delay and identifying associated factors is essential for effective tuberculosis control. We systemically analysed data obtained from the Korea Tuberculosis Cohort in 2019 by classifying delays as presentation and healthcare delays of pulmonary tuberculosis (PTB). Of 6593 patients with active PTB, presentation and healthcare delays were recorded in 4151 and 5571 patients, respectively. The median presentation delay was 16.0 (5.0-40.0) days. Multivariable logistic regression analysis showed that longer presentation delays were associated with neuropsychiatric disease [adjusted odds ratio (OR) 2.098; 95% confidence interval (CI) 1.639-2.687; p < 0.001] and heavy alcohol intake (adjusted OR 1.505; 95% CI 1.187-1.907; p < 0.001). The median healthcare delay was 5.0 (1.0-14.0) days. A longer healthcare delay was associated with malignancy (adjusted OR 1.351; 95% CI 1.069-1.709; p = 0.012), autoimmune disease (adjusted OR 2.445; 95% CI 1.295-4.617; p = 0.006), and low bacterial burden manifested as an acid-fast bacillus smear-negative and tuberculosis polymerase chain reaction-negative status (adjusted OR 1.316; 95% CI 1.104-1.569; p = 0.002). Active case-finding programmes need to focus on patients with heavy alcoholism or neuropsychiatric diseases. To ensure early PTB detection, healthcare providers must carefully monitor patients with malignancy, autoimmune disease, or a high index of suspicion for PTB.

Development of Various Diabetes Prediction Models Using Machine Learning Techniques

BACKGROUND

There are many models for predicting diabetes mellitus (DM), but their clinical implication remains vague. Therefore, we aimed to create various DM prediction models using easily accessible health screening test parameters.

METHODS

Two sets of variables were used to develop eight DM prediction models. One set comprised 62 easily accessible examination results of commonly used variables from a tertiary university hospital. The second set comprised 27 of the 62 variables included in the national routine health checkups. Gradient boosting and random forest algorithms were used to develop the models. Internal validation was performed using the stratified 10-fold cross-validation method.

RESULTS

The area under the receiver operating characteristic curve (ROC-AUC) for the 62-variable DM model making 12-month predictions for subjects without diabetes was the largest (0.928) among those of the eight DM prediction models. The ROC-AUC dropped by more than 0.04 when training with the simplified 27-variable set but still showed fairly good performance with ROC-AUCs between 0.842 and 0.880. The accuracy was up to 11.5% higher (from 0.807 to 0.714) when fasting glucose was included.

CONCLUSION

We created easily applicable diabetes prediction models that deliver good performance using parameters commonly assessed during tertiary university hospital and national routine health checkups. We plan to perform prospective external validation, hoping that the developed DM prediction models will be widely used in clinical practice.

Development of a Chatbot Program for Follow-Up Management of Workers' General Health Examinations in Korea: A Pilot Study

(1) Background: Follow-up management of workers’ general health examination (WGHE) is important, but it is not currently well done. Chatbot, a type of digital healthcare tool, is used in various medical fields but has never been developed for follow-up management of WGHE in Korea. (2) Methods: The database containing results and explanations related to WGHE was constructed. Then, the channel, which connects users with the database was created. A user survey regarding effectiveness was administered to 23 healthcare providers. Additionally, interviews on applicability for occupational health services were conducted with six nurses in the agency of occupational health management. (3) Results: Chatbot was implemented on a small scale on the Amazon cloud service (AWS) EC2 using KaKaoTalk and Web Chat as user channels. Regarding the effectiveness, 21 (91.30%) rated the need for chatbots as very high; however, 11 (47.83%) rated the usability as not high. Of the 23 participants, 14 (60.87%) expressed overall satisfaction. Nurses appreciated the chatbot program as a method for resolving accessibility and as an aid for explaining examination results and follow-up management. (4) Conclusions: The effectiveness of WGHE and the applicability in the occupational health service of the chatbot program for follow-up management can be confirmed.

Association of Participation in Health Check-ups with Risk Factors for Cardiovascular Diseases

BACKGROUND

We compared the risk factors for cardiovascular diseases (CVDs) among Koreans who did and did not participate in national periodic health check-ups, after adjustment for demographic factors, socioeconomic status, and lifestyle factors.

METHODS

This cross-sectional study used data from the Korea National Health and Nutrition Examination Survey (KNHANES) from 2007 to 2018. Study subjects were classified as participants or non-participants in health check-ups, based on attendance at national periodic health check-ups during the previous two years.

RESULTS

Comparison of participants and non-participants in health check-ups indicated statistically significant differences in age, gender, region, education level, monthly income, employment status, obesity, smoking, alcohol consumption, exercise, and marital status. After adjustment for demographic, socioeconomic factors, and health-related behaviors, woman non-participants were more likely to have metabolic syndrome, pre-hypertension, hypertension, prediabetes, and diabetes, and man non-participants were more likely to have pre-diabetes and diabetes.

CONCLUSION

Subjects who participated in periodic health check-ups had fewer CVD-related risk factors than non-participants. Thus, health care providers should encourage non-participants to attend periodic health check-ups so that appropriate interventions can be implemented and decrease the risk for CVDs in these individuals.

All-cause mortality, cardiovascular mortality, and incidence of cardiovascular disease according to a screening program of cardiovascular risk in South Korea among young adults: a nationwide cohort study

OBJECTIVES

We aimed to determine whether there are any differences in all-cause and cause-specific mortality with cardiovascular disease (CVD) risk between health screening attenders and non-attenders among young adults.

STUDY DESIGN

We performed a retrospective cohort study using claim data from the Korean National Health Insurance Service database.

METHODS

Individuals aged 20-39 years who had received health screening at least once between 2002 and 2005 were classified as attenders, and the others were classified as non-attenders. After propensity score matching according to attendance of health screening, 2,060,409 attenders and 2,060,409 non-attenders were included. We estimated adjusted hazard ratios (HRs) and 95% confidence interval (CI) for all-cause mortality, cause-specific mortality, and hospitalization of CVD from 2006 to 2015.

RESULTS

Survival from all-cause mortality was greater among attenders than among non-attenders (log rank P < 0.001). Similarly, death from CVD (log rank P = 0.007) and CVD events (log rank P < 0.001) were less likely among attenders. The risk for all-cause mortality in attenders was significantly lower than that in non-attenders (HR = 0.83, 95% CI = 0.81 to 0.84). The risk for CVD mortality (HR = 0.80, 95% CI = 0.73 to 0.87) and hospitalization of CVD (HR = 0.92, 95% CI = 0.91 to 0.94) were lower in attenders. In stratified analyses, the risk for all-cause and cause-specific mortalities was lower among attenders regardless of insurance type.

CONCLUSIONS

Among young adults, the risk for all-cause mortality, CVD mortality, and hospitalization of CVD were lower for those who underwent health screenings. Future studies that evaluate the cost-effectiveness of health screening with additional consideration of psychosocial aspects are needed.

Clinical profiles of subclinical disease among pulmonary tuberculosis patients: a prospective cohort study in South Korea

Background

Subclinical tuberculosis (TB) is a potential target for public health intervention because its early identification may reduce TB transmission. We aimed to describe the clinical and laboratory findings of subclinical disease among pulmonary TB patients and compared treatment outcomes for subclinical and active diseases.

Methods

In this prospective cohort study, we enrolled adult patients aged ≥ 19 years with pulmonary TB between 2016 and 2018. Subclinical TB was defined as radiographic or microbiologic test results consistent with TB without clinical symptoms. We implemented a two-stage symptom assessment using a predefined TB symptom checklist. Demographic, clinical, and laboratory data were compared between subclinical and active diseases using multivariable binary logistic regression analysis. We evaluated treatment outcomes in the drug-susceptible cohort.

Results

Among 420 enrolled patients, 81 (19.3%) had subclinical TB. Multivariable analysis showed that age < 65 years was the only variable significantly associated with subclinical disease. Subclinical disease had a significantly lower proportion of acid-fast bacilli smear and culture positivity and multiple lobe involvement compared to active disease. The white blood cell counts, platelet counts, and C-reactive protein levels were significantly higher among patients with active disease than among those with subclinical disease. Among 319 patients with treatment success in the drug-susceptible cohort, six (1.9%) recurrent cases were identified, and all were active disease. Patients with subclinical disease had a higher proportion of favourable outcomes; however, its odds ratio was insignificant.

Conclusions

Nearly one-fifth of tuberculosis cases were subclinical in South Korea. Despite its milder clinical presentation and lower level of inflammatory markers, the treatment outcomes of subclinical TB were not significantly different from that of active disease.

Validity assessment of self-reported smoking status in firefighters using the urine cotinine test

BACKGROUND

In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters.

METHODS

This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results.

RESULTS

The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease.

CONCLUSIONS

In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.

Body Weight Fluctuation as a Risk Factor for Type 2 Diabetes: Results from a Nationwide Cohort Study

We aimed to investigate how body weight fluctuation affects the risk of developing type 2 diabetes by conducting a nationwide cohort study. A total of 3,855,884 participants from the National Health Insurance System health check-up data from 2012 were included in this study, and follow-up continued until 2016. Body weight was measured at least thrice between 2009 and 2012. Body weight variability (BWV) was estimated using average successive variability (ASV) indices. Cox proportional hazards regression models were used to evaluate the association of BWV with the risk of type 2 diabetes using hazard ratios (HRs) and 95% confidence intervals (CIs). Body weight fluctuation was associated with a higher risk of incident diabetes after adjustment for confounders (HR 1.10, 95% CI 1.07, 1.12 in the highest BWV quartile compared to the lowest). Regardless of the weight change status, the highest ASV quartile of BWV increased the risk for diabetes. Even subjects with a normal glucose tolerance status and those aged under 65 years had a higher risk of diabetes if their body weight highly fluctuated during the follow-up years. Our results suggest that body weight variability is an independent risk factor for diabetes. It is important to pay attention to frequent body weight fluctuations.

Change in Waist Circumference With Continuous Use of a Smart Belt: An Observational Study

Background

Health insurers and policymakers are trying to prevent and reduce cardiovascular diseases due to obesity. A smart belt that monitors activity and waist circumference is a new concept for conquering obesity and may be a promising new strategy for health insurers and policymakers.

Objective

This preliminary study evaluated whether the use of a smart belt was associated with a decrease in waist circumference.

Methods

In the manufacturer’s database, there were data on a total of 427 men at baseline. A total of 223, 81, and 27 users kept using the smart belt for 4, 8, and 12 weeks, respectively. Paired t tests and repeated measures analysis of variance (ANOVA) were used to identify the change in waist circumference at specified time intervals (at 4, 8, and 12 weeks). In addition, a linear mixed model was used to incorporate all users’ waist circumference data at each time point. Preexisting data on waist circumference and self-reported demographics were obtained from the manufacturer of the smart belt (WELT Corporation, South Korea).

Results

Compared with baseline, the waist circumference (cm) decreased significantly at all time points: –0.270 for week 4, –0.761 for week 8, and –1.972 for week 12 (all P<.01). Although each paired t test had a different sample size because of loss to follow-up, the differences between baseline and each subsequent week increased. Equal continuous reduction in waist circumference was observed with the ANOVA and mixed model analysis (beta=–0.158 every week).

Conclusions

The smart belt is a newly developed, wearable device that measures real-time steps, sedentary time, and waist circumference. In this study, we showed that wearing the smart belt was associated with reducing waist circumference over 12 weeks. This direct-to-consumer smart health device may contribute toward reducing the risk of obesity and related conditions and controlling increasing health costs for health insurers.

Knowing is not half the battle: Impacts of information from the National Health Screening Program in Korea

Health screening provides information on disease risk and diagnosis, but whether this promotes health is unclear. We estimate the impacts of information provided by Korea's National Health Screening Program by applying a regression discontinuity design around different biomarker thresholds of diabetes, obesity, and hyperlipidemia risk using administrative data that includes medical claims, biomarkers, and behavioral surveys over four years after screening. Generally, we find limited responses to disease risk information alone. However, we find evidence for weight loss around the high risk threshold for diabetes, where information is combined with active prompting for a secondary examination for diagnosis and treatment.

End-stage Renal Disease and Risk of Active Tuberculosis: a Nationwide Population-Based Cohort Study

BACKGROUND

The converging epidemics of tuberculosis (TB) and end-stage renal disease (ESRD) have generated a significant public health burden, however, previous studies have been limited to a small number of patients. This nationwide cohort study aimed to assess the rate of developing active TB among patients receiving dialysis for ESRD.

METHODS

The Korean national health insurance database was used to identify patients receiving dialysis for new-onset ESRD during 2004-2013, who were propensity score matched to an equivalent number of non-dialysis subjects from the general population. The incidences of active TB in the ESRD and control cohorts were calculated for 2004-2013, and multivariable Cox proportional hazards model was used to evaluate the ESRD-related risk of active TB.

RESULTS

During 2004-2013, 59,584 patients received dialysis for newly diagnosed ESRD. In the dialysis and control cohorts, 457 (0.8%) and 125 (0.2%) cases of active TB were detected, respectively. Patients with ESRD were associated with a significantly higher risk of active TB compared to the controls (incidence rate ratio, 4.80). The ESRD cohort had an independently elevated risk of active TB (adjusted hazard ratio, 4.39; 95% confidence interval, 3.60-5.37).

CONCLUSION

We found that patients receiving dialysis for ESRD had an elevated risk of active TB. These results highlight the need for detailed and well-organised guidelines for active TB screening among patients with ESRD.

Effect of Change in Total Cholesterol Levels on Cardiovascular Disease Among Young Adults

BACKGROUND

Although high serum cholesterol in young adults is known to be a predictor for cardiovascular events, there is not enough evidence for the association of cholesterol level change with cardiovascular disease (CVD). This study aimed to evaluate whether the change in cholesterol is associated with incidence of CVD among young adults.

METHODS AND RESULTS

We examined 2 682 045 young adults (aged 20-39 years) who had undergone 2 consecutive national health check-ups provided by Korean National Health Insurance Service between 2002 and 2005. Cholesterol levels were classified into low (<180 mg/dL), middle (180-240 mg/dL) and high (≥240 mg/dL). CVD events were defined as ≥2 days hospitalization attributable to CVD for 10 years follow-up. Increased cholesterol levels were significantly associated with elevated ischemic heart disease risk (adjusted hazard ration [aHR]=1.21; 95% confidence interval [CI]=1.03-1.42 in low-high group and aHR=1.21; 95% CI=1.15-1.27 in middle-high group) and cerebrovascular disease (CEVD) risk (aHR=1.24; 95% CI=1.05-1.47 in low-high group and aHR=1.09; 95% CI=1.02-1.16 in middle-high group). Decreased cholesterol levels were associated with reduced ischemic heart disease risk (aHR=0.91; 95% CI=0.88-0.95 in middle-low group, aHR=0.65; 95% CI=0.56-0.75 in high-low group and aHR=0.68; 95% CI=0.65-0.73 in high-middle group). Furthermore, lower cerebrovascular disease risk (aHR=0.76; 95% CI=0.62-0.92) was observed in the high-low group compared with patients with sustained high cholesterol.

CONCLUSIONS

The findings of our study indicate that increased cholesterol levels were associated with high CVD risk in young adults. Furthermore, young adults with decreased cholesterol levels had reduced risk for CVD.

Association of change in total cholesterol level with mortality: A population-based study

Background

Hypercholesterolemia is a well-established risk factor for coronary heart disease, but the association between cholesterol level change and mortality is not fully understood. We aimed to investigate the association of 2 year (2002–2003 to 2004–2005) change in cholesterol with all-cause and cause-specific mortality in a population-based cohort study.

Methods and findings

The study population consisted of 269,391 participants aged more than 40 years who were free of myocardial infarction, stroke and cancer using the Korean National Health Insurance Service—National Health Screening Cohort. Cholesterol levels were classified into 1st, 2nd and 3rd tertiles during each of the first and second health examinations, respectively. The participants were followed-up for all-cause and cause-specific mortality from 1 January 2006 to 31 December 2013. Compared to participants who stayed within the 2nd tertile group for cholesterol during both the first and second examinations, participants who became or maintained cholesterol levels to the 1st tertile during the second examination had increased risk of all-cause mortality [adjusted hazard ratio (aHR) with 95% confidence interval (95% CI) = 1.28 (1.18–1.38) in 1st/1st, 1.16 (1.07–1.26) in 2nd/1st and 1.47 (1.32–1.64) in 3rd/1st tertile levels, respectively]. In addition, increased or persistent high cholesterol levels to the 3rd tertile was associated with elevated risk for all-cause mortality [aHR (95% CI) = 1.10 (1.01–1.20) in 1st/2nd, 1.16(1.03–1.31) in 1st/3rd and 1.15(1.05–1.25) in 3rd/3rd tertile levels].

Conclusions

Changes in cholesterol levels in either direction to low cholesterol or persistently low cholesterol levels were associated with higher risk of mortality. Particularly, spontaneous decline in cholesterol levels may be a marker for worsening health conditions.

Status of hypertension screening in the Korea National General Health Screening Program: a questionnaire survey on 210 screening centers in two metropolitan areas

BACKGROUND

The purpose of this survey was to evaluate the performance of hypertension screening in medical institutions conducting the national general health screening program of the Republic of Korea.

METHODS

We contacted 700 medical institutions of Seoul and Incheon areas which performed the national general health screening program in 2016, and 210 of them completed telephone survey. The questions asked in the survey include equipment, environment, personnel and quality control procedures for blood pressure (BP) measurement, and interpretation of the measurements.

RESULTS

A majority of the responding screening centers used oscilloscope sphygmomanometers (51.9%), had only one-sized cuff (65.2%), and measured BP in open space (54.3%). BP levels were measured mainly by nurses (62.0%) and doctors (25.0%), after a 1 to10 minutes (84.9%) of resting period. A 75.2% of screening centers regularly calibrated sphygmomanometers, 81.4% had a manual for BP measurement, and 59.0% had a training program. A 80.0% of respondents answered that they used averages of multiple BP measurements to determine an individual's BP level, and 82.9% answered that criteria for hypertension was systolic BP ≥140 mmHg and/or diastolic BP ≥ 90 mmHg. If a screening finds an individual with hypertension, 82.9% of centers recommend revisiting for a second BP measurement rather than start medication immediately.

CONCLUSION

In most medical institutions performing general health screening program, certified medical personnel measure BP and interpret the results according to established protocols. However, there is room for improvement in the equipment, environment and quality control procedures for BP measurement.

Effectiveness of workers' general health examination in Korea by health examination period and compliance: retrospective cohort study using nationwide data

BACKGROUND

Our study evaluated the effectiveness of the Workers' General Health Examination by health examination period and compliance.

METHODS

A retrospective cohort of the health examination participants in 2006 (baseline year: N = 6,527,045) was used. We identified newly occurring cardio-cerebrovascular disease over 7 years (from 2007 to 2013). After stratification by age, sex, and national health insurance type, we identified 7 years' cumulative incidence of cardio-cerebrovascular disease by health examination compliance and estimated its relative risk by health examination period and compliance.

RESULTS

The compliant group presented a lower cumulative incidence of cardio-cerebrovascular disease than the non-compliant group; this result was consistent across sex, working age (40s and 50s), and workplace policyholder. Relative risk of cardio-cerebrovascular disease by health examination period (1 and 2 years) showed statistically significant results in ischemic heart disease for male participants. Of men in their 40s, office workers (over a 2-year period) presented statistically higher relative risk of ischemic heart disease than non-office workers (over a 1-year period: 1.03; 95% confidence interval, 1.02-1.03). However, there were no consistent results in ischemic cerebrovascular disease and hemorrhagic cerebrovascular disease for men or cardio-cerebrovascular disease for women.

CONCLUSION

A 1-year period of Workers' General Health Examinations in non-office workers had a more significant prevention effect on ischemic heart disease than a 2-year period in office workers among working age (40s-50s) men. It is, however, necessary to consider that prevention of cardio-cerebrovascular disease can be partially explained by their occupational characteristics rather than by health examination period.

Diabetes Mellitus and Site-specific Colorectal Cancer Risk in Korea: A Case-control Study

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.

Effects of Disease Detection on Changes in Smoking Behavior

PURPOSE

This study was conducted to investigate the effect that detection of chronic disease via health screening programs has on health behaviors, particularly smoking.

MATERIALS AND METHODS

We analyzed national health insurance data from 2007 and 2009. Subjects who were 40 years of age in 2007 and eligible for the life cycle-based national health screening program were included. The total study population comprised 153,518 individuals who participated in the screening program in 2007 and follow-up screening in 2009. Multiple logistic regression analyses were conducted by sex, with adjustment for health insurance type, socioeconomic status, body mass index, diabetes, hypertension, hyperlipidemia, and family history of cardiovascular and/or neurovascular disease.

RESULTS

Among men with smoking behavior changes, those newly diagnosed with hyperlipidemia were more likely to show a positive health behavior change, such as smoking cessation, and were less likely to have a negative behavior change (e.g., smoking initiation). Additionally, men newly diagnosed with diabetes showed lower rates of negative health behavior changes compared to those without disease. Body mass index (BMI)≥25, compared to BMI<23, showed higher rates of positive health behavior changes and lower rates of negative health behavior changes. Newly diagnosed chronic disease did not influence smoking behavior in women.

CONCLUSION

Smoking behavior changes were only detected in men who participated in health screening programs. In particular, those newly diagnosed with hyperlipidemia were more likely to stop smoking and less likely to start smoking.

Regional factors associated with participation in the national health screening program: a multilevel analysis using national data

High participation rates are important for maximizing the effects of a health screening program. Previous studies have suggested that individual or regional characteristics have effects on health behaviors. In this study, we investigated the determinants of participation in the National Screening Program for Transitional Ages by simultaneously analyzing individual and area-level factors by multilevel analysis. A total of 1,081,216 subjects, aged 40 and 66 yr and nested in 254 areas, were included. There was a significant variation in participation rates across the areas even after adjusting for individual and area-level variables. Among the individual-level variables, increasing age, sex, higher income, and mild disability grade were associated with a higher participation rate. In urban areas, the 40-yr-old group had higher participation rates than the 66-yr-old group. Deprived areas had significantly high participation rates for both age groups. The number of screening centers per 1,000 inhabitants had no significant effect on participation in the screening program. In conclusion, regional characteristics are associated with participation rates independent of personal features and regional factors have differential effects with respect to age. A multi-dimensional approach is recommended to promote participation in health screening programs.

National screening program for transitional ages in Korea: a new screening for strengthening primary prevention and follow-up care

Screening can effectively reduce mortality and morbidity in some diseases. In Korea, a practical national screening program for chronic disease was launched in 1995 and several problems were discussed. The program focused primarily on disease detection without follow-up care. In addition, the test items were uniform regardless of subject's age, sex, or risk factors; and people with low socioeconomic status were excluded. To improve the quality of program, a new national screening program called the "National Screening Program for Transitional Ages (NSPTA)" was initiated in 2007. It targeted two age groups, ages 40 and 66, because these ages are important transition periods in one's lifecycle. Follow-up care and education for lifestyle modification has been intensified; screening tests for mental health problems and osteoporosis have been introduced. The pool of eligible participants has been expanded to include people supported by Medicaid. This review aimed to describe the contents, process, and characteristics of the NSPTA and to compare it with the previous program. In addition, some preliminary results from 2007 to 2009 were presented. Lastly, we suggest several points that need to be considered to improve the program such as enhancement of participation rates, necessity of specialized committee and research for current screening program to be supported by evidence.