Prognostic value of resting heart rate in predicting undiagnosed diabetes in adults: Korean National Health and Nutrition Examination Survey 2008-2018.

BACKGROUND AND AIM: Although resting heart rate (RHR) is associated with prevalence and incidence of diabetes, whether it is associated with undiagnosed diabetes is still unclear. We aimed to investigate whether the RHR is associated with the prevalence of undiagnosed diabetes in a large Korean national dataset. METHODS AND RESULTS: The Korean National Health and Nutrition Examination Survey data from 2008 to 2018 were used. After screening, 51,637 participants were included in this study. The odds ratios and 95% confidence intervals (CIs) for undiagnosed diabetes were calculated using multivariable-adjusted logistic regression analyses. Analyses showed that participants with a RHR of ≥90 bpm showed a 4.00- (95% CI: 2.77-5.77) and 3.21-times (95% CI: 2.01-5.14) higher prevalence of undiagnosed diabetes for men and women, respectively, than those with a RHR of <60 bpm. The linear dose-response analyses showed that each 10-bpm increment in RHR was associated with a 1.39- (95% CI: 1.32-1.48) and 1.28-times (95% CI: 1.19-1.37) higher prevalence of undiagnosed diabetes for men and women, respectively. In the stratified analyses, the positive association between RHR and the prevalence of undiagnosed diabetes was tended to be stronger among those who were younger (age: <40 years) and lean (BMI: <23 kg/m2). CONCLUSIONS: Elevated RHR was significantly associated with a higher prevalence of undiagnosed diabetes in Korean men and women, independent of demographic, lifestyle, and medical factors. Accordingly, the value of RHR as a clinical indicator and health marker, especially in reducing the prevalence of undiagnosed diabetes, is suggestible.

The predictive value of resting heart rate in identifying undiagnosed diabetes in Korean adults: Korea National Health and Nutrition Examination Survey.

OBJECTIVES: The purpose of this study was (1) to examine whether the addition of resting heart rate (RHR) to the existing undiagnosed diabetes mellitus (UnDM) prediction model would improve predictability, and (2) to develop and validate UnDM prediction models by using only easily assessable variables such as gender, RHR, age, and waist circumference (WC). METHODS: Korea National Health and Nutrition Examination Survey (KNHANES) 2010, 2012, 2014, 2016 data were used to develop the model (model building set, n=19,675), while the data from 2011, 2013, 2015, 2017 were used to validate the model (validation set, n=19,917). UnDM was defined as a fasting glucose level ≥126 mg/dL or glycated hemoglobin ≥6.5%; however, doctors have not diagnosed it. Statistical package for the social sciences logistic regression analysis was used to determine the predictors of UnDM. RESULTS: RHR, age, and WC were associated with UnDM. When RHR was added to the existing model, sensitivity was reduced (86 vs. 73%), specificity was increased (49 vs. 65%), and a higher Youden index (35 vs. 38) was expressed. When only gender, RHR, age, and WC were used in the model, a sensitivity, specificity, and Youden index of 70%, 67%, and 37, respectively, were observed. CONCLUSIONS: Adding RHR to the existing UnDM prediction model improved specificity and the Youden index. Furthermore, when the prediction model only used gender, RHR, age, and WC, the outcomes were not inferior to those of the existing prediction model.

Development of the Korean Global Physical Activity Questionnaire: reliability and validity study.

The goal of this study was to develop a Korean version of the Global Physical Activity Questionnaire (K-GPAQ) and to examine its reliability and validity. The English version of the GPAQ was translated to the Korean language (K-GPAQ) via forward-backward translation. Reliability of the K-GPAQ was evaluated using a one-week interval test-retest method with 115 individuals. Criterion-related validity of the K-GPAQ was examined with 199 participants using accelerometers. Cohen's kappa and Spearman's correlation coefficients were used to measure test-retest reliability and validity, respectively. A Bland-Altman analysis was used to assess agreement between physical activity (PA) levels measured via K-GPAQ and the accelerometer. Coefficients for the reliability of the K-GPAQ showed moderate agreement for recreational PA and slight agreement for work-related PA (Cohen's kappa: 0.60-0.67 for recreational PA and 0.30-0.38 for work-related PA and Spearman's rho: 0.27-0.47 for work-related PA and 0.53-0.70 for recreational PA). Criterion validity of the total amount of PA, as measured by the K-GPAQ and the accelerometer, showed a weak but significant correlation (r = 0.34, p < 0.01). The K-GPAQ is a reliable and valid questionnaire to measure PA although K-GPAQ overestimated PA levels.

Role of allostatic load and health behaviours in explaining socioeconomic disparities in mortality: a structural equation modelling approach.

BACKGROUND: The relationship between socioeconomic status and mortality has been well established; however, the extent to which biological factors mediate this relationship is less clear, and empirical evidence from non-Western settings is limited. Allostasis, a cumulative measure of physiological dysregulation, has been proposed as the underlying mechanism linking socioeconomic status to adverse health outcomes. The current study aimed to ascertain the contribution of allostatic load (AL) and health behaviours to socioeconomic inequalities in mortality among Korean adults. METHODS: The sample comprised 70 713 middle-aged and older-aged adults, aged 40-79 years from the Korean Metabolic Syndrome Mortality Study. Using structural equation modelling (SEM), mediation analyses were performed to estimate the effects of socioeconomic position (SEP) on mortality over the follow-up and the extent to which AL, physical exercise and non-smoking status mediate the association between SEP and mortality. RESULTS: A total of 5618 deaths (7.9%) occurred during the mean follow-up of 15.2 years (SD 2.9). SEM confirmed a direct significant effect of SEP on mortality, as well as significant indirect paths through AL, physical exercise and non-smoking status. CONCLUSIONS: Our findings provide support for the mediating role of AL and health behaviours in the link between SEP and mortality. Policies designed to reduce social disparities in mortality in the long term should primarily focus on reducing stress and promoting healthy lifestyles among the socially disadvantaged groups. Future studies should further assess the role of other mediators such as psychosocial factors, which may contribute to socioeconomic inequalities in mortality.

Multinational Assessment of Accuracy of Equations for Predicting Risk of Kidney Failure: A Meta-analysis.

IMPORTANCE: Identifying patients at risk of chronic kidney disease (CKD) progression may facilitate more optimal nephrology care. Kidney failure risk equations, including such factors as age, sex, estimated glomerular filtration rate, and calcium and phosphate concentrations, were previously developed and validated in 2 Canadian cohorts. Validation in other regions and in CKD populations not under the care of a nephrologist is needed. OBJECTIVE: To evaluate the accuracy of the risk equations across different geographic regions and patient populations through individual participant data meta-analysis. DATA SOURCES: Thirty-one cohorts, including 721,357 participants with CKD stages 3 to 5 in more than 30 countries spanning 4 continents, were studied. These cohorts collected data from 1982 through 2014. STUDY SELECTION: Cohorts participating in the CKD Prognosis Consortium with data on end-stage renal disease. DATA EXTRACTION AND SYNTHESIS: Data were obtained and statistical analyses were performed between July 2012 and June 2015. Using the risk factors from the original risk equations, cohort-specific hazard ratios were estimated and combined using random-effects meta-analysis to form new pooled kidney failure risk equations. Original and pooled kidney failure risk equation performance was compared, and the need for regional calibration factors was assessed. MAIN OUTCOMES AND MEASURES: Kidney failure (treatment by dialysis or kidney transplant). RESULTS: During a median follow-up of 4 years of 721,357 participants with CKD, 23,829 cases kidney failure were observed. The original risk equations achieved excellent discrimination (ability to differentiate those who developed kidney failure from those who did not) across all cohorts (overall C statistic, 0.90; 95% CI, 0.89-0.92 at 2 years; C statistic at 5 years, 0.88; 95% CI, 0.86-0.90); discrimination in subgroups by age, race, and diabetes status was similar. There was no improvement with the pooled equations. Calibration (the difference between observed and predicted risk) was adequate in North American cohorts, but the original risk equations overestimated risk in some non-North American cohorts. Addition of a calibration factor that lowered the baseline risk by 32.9% at 2 years and 16.5% at 5 years improved the calibration in 12 of 15 and 10 of 13 non-North American cohorts at 2 and 5 years, respectively (P = .04 and P = .02). CONCLUSIONS AND RELEVANCE: Kidney failure risk equations developed in a Canadian population showed high discrimination and adequate calibration when validated in 31 multinational cohorts. However, in some regions the addition of a calibration factor may be necessary.

Preservation of a traditional Korean dietary pattern and emergence of a fruit and dairy dietary pattern among adults in South Korea: secular transitions in dietary patterns of a prospective study from 1998 to 2010.

Transitions in nutrition patterns tend to emerge through industrialization and economic development. We hypothesized that the dietary patterns among South Korean adults who were 20 years or older have changed significantly from 1998 to 2010. Herein, a repeated cross-sectional analysis of data was followed for 140601 adults. We noted changes in consumption, after adjusting for age, sex, body mass index, and exercise, and tested the trends across the study period. Factor and cluster analyses were used to derive dietary patterns. A decrease in traditional Korean food consumption, including cereals, vegetables (252-176 g), and Kimchi (127-82 g), occurred, whereas fruit (172-252 g), egg, and fried food intakes increased (P < .05). Total daily energy intake declined steadily from 1931 in 1998 to 1691 kcal in 2010. Carbohydrate intakes were unchanged over the study period; however, fat-derived energy intake increased slightly from 19.7% to 20.0% (P < .05). Our factor and cluster analyses identified 3 dietary patterns: "Korean" diet (rice, vegetables, and Kimchi), "Western" diet (soda, eggs, and oil), and "New" diet (low sugar and high fruit and dairy product intakes). Compared to 1998, approximately 40% of participants still followed a Korean diet in 2010. Interestingly, the popularity of the Western diet fell by approximately 20%, whereas the new diet pattern increased 2-fold over the study period. Overall, these data show secular trends in dietary patterns that included a preservation of the traditional Korean diet and the emergence of a new diet pattern, and it demonstrated a unique transition in food and nutrient intakes in Korea.

Cancer prevention in Asia: resource-stratified guidelines from the Asian Oncology Summit 2013.

With economic growth in Asia, cancer has become increasingly prominent as a major health problem. However, discrepancies in infrastructure, economics, and development exist within and between Asian countries. We assess means of primary and secondary prevention for cervical, breast, colorectal, and hepatocellular cancer, and offer recommendations according to resource levels. Primary prevention by health education, lifestyle modification, and avoidance of risk factors should be made available at all resource levels. When resources allow, human papillomavirus and hepatitis B vaccinations should be given to reduce the risk of cervical and hepatocellular cancer, and genetic testing should be offered to detect increased susceptibility to colorectal and breast cancer. Secondary prevention by effective yet affordable screening for precancerous lesions or by early detection of cancer should be offered, followed by appropriate treatment.

Comparison of risk prediction using the CKD-EPI equation and the MDRD study equation for estimated glomerular filtration rate.

CONTEXT: The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation more accurately estimates glomerular filtration rate (GFR) than the Modification of Diet in Renal Disease (MDRD) Study equation using the same variables, especially at higher GFR, but definitive evidence of its risk implications in diverse settings is lacking. OBJECTIVE: To evaluate risk implications of estimated GFR using the CKD-EPI equation compared with the MDRD Study equation in populations with a broad range of demographic and clinical characteristics. DESIGN, SETTING, AND PARTICIPANTS: A meta-analysis of data from 1.1 million adults (aged ≥ 18 years) from 25 general population cohorts, 7 high-risk cohorts (of vascular disease), and 13 CKD cohorts. Data transfer and analyses were conducted between March 2011 and March 2012. MAIN OUTCOME MEASURES: All-cause mortality (84,482 deaths from 40 cohorts), cardiovascular mortality (22,176 events from 28 cohorts), and end-stage renal disease (ESRD) (7644 events from 21 cohorts) during 9.4 million person-years of follow-up; the median of mean follow-up time across cohorts was 7.4 years (interquartile range, 4.2-10.5 years). RESULTS: Estimated GFR was classified into 6 categories (≥90, 60-89, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m(2)) by both equations. Compared with the MDRD Study equation, 24.4% and 0.6% of participants from general population cohorts were reclassified to a higher and lower estimated GFR category, respectively, by the CKD-EPI equation, and the prevalence of CKD stages 3 to 5 (estimated GFR <60 mL/min/1.73 m(2)) was reduced from 8.7% to 6.3%. In estimated GFR of 45 to 59 mL/min/1.73 m(2) by the MDRD Study equation, 34.7% of participants were reclassified to estimated GFR of 60 to 89 mL/min/1.73 m(2) by the CKD-EPI equation and had lower incidence rates (per 1000 person-years) for the outcomes of interest (9.9 vs 34.5 for all-cause mortality, 2.7 vs 13.0 for cardiovascular mortality, and 0.5 vs 0.8 for ESRD) compared with those not reclassified. The corresponding adjusted hazard ratios were 0.80 (95% CI, 0.74-0.86) for all-cause mortality, 0.73 (95% CI, 0.65-0.82) for cardiovascular mortality, and 0.49 (95% CI, 0.27-0.88) for ESRD. Similar findings were observed in other estimated GFR categories by the MDRD Study equation. Net reclassification improvement based on estimated GFR categories was significantly positive for all outcomes (range, 0.06-0.13; all P < .001). Net reclassification improvement was similarly positive in most subgroups defined by age (<65 years and ≥65 years), sex, race/ethnicity (white, Asian, and black), and presence or absence of diabetes and hypertension. The results in the high-risk and CKD cohorts were largely consistent with the general population cohorts. CONCLUSION: The CKD-EPI equation classified fewer individuals as having CKD and more accurately categorized the risk for mortality and ESRD than did the MDRD Study equation across a broad range of populations.

Public health challenges of electronic cigarettes in South Korea.

Electronic cigarettes (e-cigarrettes) were recently introduced and advertised as a smoking cession device in South Korea. As the social norm to quit smoking has gained hold in the country, the number of e-cigarette users is growing rapidly. This phenomenon should be urgently considered, because of the lack of research that has been conducted to examine the safety of e-cigarettes and its efficacy as a smoking cessation aid. This paper raises several public health concerns on e-cigarettes in South Korea. Uncertain regulations of the government on e-cigarettes are contributing to an increase of e-cigarette users and allowing the e-cigarette industry to circumvent existing regulations. The aggressive marketing activity of this industry is also a core factor that is responsible for the rapid increase of e-cigarette use, in particular among the youth. Following the enforcement of tobacco control, some cigarette smokers may be encouraged to purchase e-cigarettes in order to circumvent the regulations, even though the dual use of e-cigarette and cigarette may be more harmful. Until there is clear evidence of the e-cigarette's safety, it is recommended that the industry's marketing and promotional activities be banned and closely monitored, and public campaigns be initiated to educate the public regarding e-cigarettes.

Differential parental transmission of markers in BCL3 among Korean cleft case-parent trios.

OBJECTIVES: Isolated cleft lip with or without cleft palate (CL/P) is among the most common human birth defects, with a prevalence of approximately 1 in 700 live births. The B-Cell Leukemia/lymphoma 3 (BCL3) gene has been suggested as a candidate gene for CL/P based on association and linkage studies in some populations. This study tests for an association between markers in BCL3 and isolated, non-syndromic CL/P using a case-parent trio design, while considering parent-of-origin effects. METHODS: Forty case-parent trios were genotyped for two single nucleotide polymorphisms (SNPs) in the BCL3 gene. We performed a transmission disequilibrium test (TDT) on individual SNPs, and the FAMHAP package was used to estimate haplotype frequencies and to test for excess transmission of multi-SNP haplotypes. RESULTS: The odds ratio for transmission of the minor allele, OR (transmission), was significant for SNP rs8100239 (OR=3.50, p=0.004) and rs2965169 (OR=2.08, p=0.027) when parent-of-origin was not considered. Parent-specific TDT revealed that SNP rs8100239 showed excess maternal transmission. Analysis of haplotypes of rs2965169 and rs8100239 also suggested excess maternal transmission. CONCLUSIONS: BCL3 appears to influence risk of CL/P through a parent-of-origin effect with excess maternal transmission.

Medical expenditure of national health insurance attributable to smoking among the Korean population.

OBJECTIVES: The purpose of this study was to determine the population-attributable risk (PAR) and estimate the total medical expenditure of the Korean National Health Insurance (KNHI) due to smoking. METHODS: We used data from the Korean Cancer Prevention Study of 1,178,138 Koreans aged 30 to 95. These data were available from 1992 to 2003 and covered a long-term follow-up period among the Korean population. RESULTS: The total medical expenditure of KNHI related to smoking increased by 27% from $324.9 million in 1999 to $413.7 million in 2003. By specific diseases, smoking-attributable KNHI medical expenditure was the highest for lung cancer ($74.2 million), followed by stroke ($65.3 million), COPD ($50.1 million), CHD ($49 million) and stomach cancer ($30 million). A total of 1.3 million KNHI patients were suffering from smoking-related diseases in 2003. We predicted rises in total KNHI medical expenditure related to smoking to $675.1 million (63% increase compared with that of 2003) and in the total number of KNHI patients suffering from smoking-related diseases to about 2.6 million (an approximate 100% increase compared with those in 2003) in 2015. CONCLUSIONS: We found a substantial economic burden related to the high smoking prevalence in South Korea.

Associations between smoking, screening, and death caused by cervical cancer in Korean women.

PURPOSE: Cervical cancer is a major women's health problem in the world today. The purpose of this study was to estimate the incidence and mortality rates and to investigate risk factors for cervical cancer in Korean women. MATERIALS AND METHODS: Reproductive factors, cigarette smoking, as well as the risk of incidence and death from cervical cancer were examined in a 12-year prospective cohort study of 475,398 Korean women aged 30 to 95 years who received health insurance from the National Health Insurance Corporation and who had a medical evaluation in 1992. Relative risks (RR) and 95% confidence intervals (CI) were calculated using the Cox proportional hazards model after adjusting for age, body mass index, cigarette smoking, alcohol use, menarche, parity, and Papanicolaou test status. RESULTS: This study showed that the RR of death due to cervical cancer among current smokers was two times higher compared with non- smokers (RR=2.00; 95% CI, 1.23-2.91). In addition, the RR of death due to cervical cancer among all women who smoked > or = 10 cigarettes/day was 2.4 times higher than the RR among women that had never smoked. More interestingly, those who had never been screened by Papanicolaou smears had twice the risk of death due to cervical cancer (RR =2.00; 95% CI, 1.37-1.81). CONCLUSION: Our prospective study concluded that current smokers had an increased risk of death due to cervical cancer. We suggest that the target age group for cervical cancer screening tests be reconsidered and should begin as early as possible.

Smoking cessation and risk of type 2 diabetes mellitus: Korea Medical Insurance Corporation Study.

BACKGROUND: To investigate the independent effects of smoking cessation on the risk for developing type 2 diabetes mellitus (DM) in the general population. DESIGN: An 8-year prospective study. METHODS: This prospective study started with baseline examinations in 1990 and 1992, and continued with follow-up examinations every 2 years up to 1998 and 2000. A total of 27 635 nondiabetic men, aged 35-44 years were classified as 5701 nonsmokers, 7477 ex-smokers and 14 457 sustained smokers, based on repeated self-reported questionnaires in 1992, 1994 and 1996. Baseline fasting serum glucose level and other risk factors were measured in 1990 and 1992. The outcome was newly developed DM, defined as a fasting glucose level > or =7.0 mmol/l in 1998 and 2000 (averaged). RESULTS: Over the 8 years, 1170 men (4.2%) developed DM. When compared with nonsmokers, the fully adjusted risk ratio of ex-smokers and sustained smokers for diabetes was 1.22 [95% confidence interval (CI), 0.96-1.55] and 1.60 (95% CI, 1.29-1.97), respectively. Among the ex-smokers, the risk for diabetes differed according to the quit-smoking period. Compared with nonsmokers, the fully adjusted risk ratio for DM in men who quit smoking before 1992, during 1992-1993 and during 1994-1995 was 0.95 (0.72-1.25), 1.44 (0.96-2.15) and 2.13 (1.51-3.00), respectively, after adjustment for age, baseline fasting serum glucose, weight change, baseline body mass index, family history of DM, alcohol consumption and exercise status. CONCLUSIONS: Our results support cigarette smoking as an independent and modifiable risk factor for DM. Early smoking cessation could decrease the risk for developing DM to that of nonsmokers in the long term.

[The relationship between socioeconomic position and the predicted risk of ischemic heart disease with using health risk appraisal].

OBJECTIVES: The object of this study is to assess the relationship between socioeconomic factors and the predicted 10-year risk of cardiovascular disease by using health risk appraisal of ischemic heart disease. METHODS: The study population was taken from The 2001 Korea National Health and Nutrition Survey, and it consisted of 1,566 men and 1,984 women aged 30-59. We calculated 10-year risk using the risk function of ischemic heart disease as developed by Jee. The educational level and equivalized household income were dichotomized by a 12 years education period and the median income level. Occupation was dichotomized into manual/non-manual work. We stratified the population by age (10 years) and sex, and then we rated the risk differences according to socioeconomic factors by performing t-tests for each strata. RESULTS: There were gradients of the predicted 10-year risk of ischemic heart disease with the educational level and the equivalized household income, and thet was an increasing tendency of risk differences with age. Manual workers didn't show significant risk difference from non-manual workers. CONCLUSIONS: There was definite relationship between low socioeconomic position and the predicted risk of ischemic heart disease in the future.

Direct, progressive association of cardiovascular risk factors with incident proteinuria: results from the Korea Medical Insurance Corporation (KMIC) study.

BACKGROUND: Proteinuria is a major risk factor for the progression of kidney disease and the development of cardiovascular disease. Little is known, however, about risk factors for incident proteinuria. METHODS: We conducted a 10-year prospective cohort study of 104,523 Korean men and 52,854 women, aged 35 to 59 years, who attended Korea Medical Insurance Corporation health examinations and who did not have proteinuria at baseline. Incident proteinuria was assessed at biennial examinations during the next 10 years. We performed Cox proportional hazards analyses. RESULTS: During 10 years of follow-up, proteinuria developed in 3951 men (3.8%) and 1527 women (2.9%). The adjusted relative risk (RR) of proteinuria associated with diabetes was 3.27 (95% confidence interval [CI], 2.98-3.58) in men and 2.60 (95% CI, 1.98-3.43) in women; with body mass index (calculated as weight in kilograms divided by the square of height in meters), it was 1.43 (95% CI, 1.35-1.50) in men and 1.45 (95% CI, 1.35-1.55) in women per 5-U increment. Compared with subjects with serum cholesterol levels of less than 200 mg/dL (< 5.18 mmol/L), the adjusted RRs associated with serum cholesterol levels of 200 to 239 mg/dL (5.18-6.19 mmol/L) and 240 mg/dL or more (> or = 6.22 mmol/L) were 1.13 (95% CI, 1.05-1.21) and 1.40 (95% CI, 1.27-1.54), respectively, in men and 1.14 (95% CI, 1.01-1.28) and 1.22 (95% CI, 1.00-1.37), respectively, in women. Persons with stages 1 and 2 hypertension had a greater adjusted RR of incident proteinuria compared with those with normal blood pressure (1.62 [95% CI, 1.47-1.79] and 2.06 [95% CI, 1.81-2.34], respectively, in men and 1.37 [95% CI, 1.14-1.65] and 2.10 [95% CI, 1.59-2.76], respectively, in women). CONCLUSIONS: Fasting glucose and cholesterol levels, body mass index, and blood pressure were direct and independent predictors of incident proteinuria in Korean adults. These associations were present even at low levels of exposure, emphasizing the importance of early detection and management of these modifiable risk factors.