Population Prevalence, Cancer Risk, and Mortality Risk of Turner Syndrome in South Korean Women Based on National Health Insurance Service Data

PURPOSE

In South Korea, investigations into Turner syndrome (TS) prevalence and TS-associated cancer and mortality are lacking. Accurate data were estimated from the National Health Insurance Service (NHIS) and the Rare Diseases Registry (RDR) records.

MATERIALS AND METHODS

Data on patients with TS who were registered in the RDR between 2007 and 2017 were collected. To estimate TS-associated cancer and mortality risk, the data were compared with data of 1:3 age-matched controls.

RESULTS

In 2017, 2054 patients with TS were identified from a total population of 26186952 South Korean women; therefore, the prevalence was 7.84 per 100000 persons. TS prevalence across 10-year interval age groups were 11.82, 23.17, 18.37, 10.49, 4.09, and 0.38 for age under 10 years, teenagers, 20s, 30s, 40s, and older than 50, respectively (per 100000 persons). The cancer risk in patients with TS was higher than that of age-matched controls over 5.3 person-years [hazard ratio (HR)=1.82, 95% confidence interval (CI) 1.01-3.27, p=0.045]. Among different types of cancer, thyroid cancer risk in patients with TS was significantly higher than that of age-matched controls (HR=2.78, 95% CI 1.06-7.26, p=0.037). We also observed that TS-associated all-cause mortality risk was higher than that of age-matched controls (HR=3.36, 95% CI 1.59-7.10, p=0.002).

CONCLUSION

National prevalence of TS was suggested, and an increased risk of TS-associated thyroid cancer and mortality were observed in this study.

A Longitudinal Retrospective Observational Study on Obesity Indicators and the Risk of Impaired Fasting Glucose in Pre- and Postmenopausal Women

The impact of obesity could differ according to menopausal status since women undergo significant physiologic and metabolic changes due to menopause. We investigated the association between various major obesity indicators and the risk of impaired fasting glucose (IFG) according to menopausal status using nationally representative data. A total of 571,286 premenopausal and 519,561 postmenopausal women who underwent both Korean National Health Insurance Service (NHIS) cancer screening in 2009 and health check-ups in 2017 were analyzed. Multivariate logistic regression analyses were used to assess the effect of independent variables of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) in 2009, on dependent variable IFG in 2017. After adjusting for potential confounders, the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of developing IFG were analyzed. In the premenopausal group, the OR of obese BMI (≥25 kg/m2, <30 kg/m2) women was increased to 2.228 (95% CI: 2.139−2.321) compared to the normal BMI (≥18.5, <23 kg/m2) women as a reference. In the postmenopausal group, there was also a higher OR of 1.778 (95% CI: 1.715−1.843) in the obese BMI women compared to the normal group. A similar association of increasing ORs for IFG was shown in both groups when stratified by WC and WHtR. This nationwide study revealed that obesity and abdominal obesity, defined by various obesity indicators, consistently increased odds of acquiring IFG after 8 years in both pre- and postmenopausal groups, with the association being more robust in the premenopausal group. Our findings suggest that weight management and lifestyle modification may require more attention in premenopausal women.

Changes in Patterns of Physical Activity and Risk of Heart Failure in Newly Diagnosed Diabetes Mellitus Patients

BACKGROUND

Exercise is recommended for type 2 diabetes mellitus (T2DM) patients to prevent cardiovascular disease. However, the effects of physical activity (PA) for reducing the risk of heart failure (HF) has yet to be elucidated. We aimed to assess the effect of changes in patterns of PA on incident HF, especially in newly diagnosed diabetic patients.

METHODS

We examined health examination data and claims records of 294,528 participants from the Korean National Health Insurance Service who underwent health examinations between 2009 and 2012 and were newly diagnosed with T2DM. Participants were classified into the four groups according to changes in PA between before and after the diagnosis of T2DM: continuously inactive, inactive to active, active to inactive, and continuously active. The development of HF was analyzed until 2017.

RESULTS

As compared with those who were continuously inactive, those who became physically active after diagnosis showed a reduced risk for HF (adjusted hazard ratio [aHR], 0.79; 95% confidence interval [CI], 0.66 to 0.93). Those who were continuously active had the lowest risk for HF (aHR, 0.77; 95% CI, 0.62 to 0.96). As compared with those who were inactive, those who exercised regularly, either performing vigorous or moderate PA, had a lower HF risk (aHR, 0.79; 95% CI, 0.69 to 0.91).

CONCLUSION

Among individuals with newly diagnosed T2DM, the risk of HF was reduced in those with higher levels of PA after diagnosis was made. Our results suggest either increasing or maintaining the frequency of PA after the diagnosis of T2DM may lower the risk of HF.

Risk Assessment of Mortality in Elderly Individuals: A Nationwide Cohort Study

INTRODUCTION

There are several methods that are used to predict emergency room visits or rehospitalization for the elderly. However, existing risk assessment models of mortality in elderly people are limited. The purpose of this study was to ascertain the factors that affect all-cause mortality and to show the risk assessment model of mortality in elderly Koreans.

METHODS

This was a cohort study conducted using the health checkup data of 246,422 individuals aged ≥60 years, which was provided by the National Health Insurance Service of South Korea between January 1, 2009, and December 31, 2012. The hazard ratios and 95% confidence intervals (CIs) of several conditions and all-cause deaths were estimated using a multivariable Cox proportional hazards model. A nomogram was constructed to visualize the risk factors of mortality; a calibration plot and area under the curve (AUC) were also used to verify the nomogram.

RESULTS

Being 85 years or older (100 points) had the greatest influence on all-cause mortality, followed by being underweight (57 points), having more than five chronic diseases (49 points), and ages 78-84 years (45 points); smoking and lack of regular exercise affected mortality to a similar degree. The calibration curves showed good agreement between predictions and observations. The AUC of our nomogram was 0.73 (95% CI: 0.72-0.73).

CONCLUSIONS

Our results showed the relationship between each condition and mortality rate among elderly individuals in Korea. Our nomogram showed a satisfactory performance in the assessment of the risk of all-cause mortality in elderly Korean people.

Validation of a Korean version of the quality-of-life profile for spine deformities (QLPSD) in patients with adolescent idiopathic scoliosis

OBJECTIVE

We aimed to evaluate the reliability and validity of the adapted Korean version of the Quality-of-Life Profile for Spine Deformities (QLPSD) questionnaire.

PATIENTS AND METHODS

English version of QLPSD was translated into Korean according to previously published guidelines. The Korean version of the QLPSD questionnaire and the Korean version of the SRS-22 was sent to 120 consecutive idiopathic scoliosis patients wearing braces recruited from the outpatient clinic. Reliability assessment and construct validity were evaluated.

RESULTS

The intraobserver reliability of all items in the questionnaire had a kappa statistic of agreement greater than 0.6. The QLPSD showed good test/re-test reliability (ICC = 0.815). The internal consistency of Cronbach's α was found to be very good (α = 0.918). The Korean version of QLPSD showed a significant correlation with the SRS-22 total score (p<0.001, r=-0.811) and single SRS-22 domains scores.

CONCLUSIONS

The adapted Korean version of the QLPSD was successfully translated and showed good measurement properties. As such, it is considered suitable for outcome assessments in Korean-speaking patients with idiopathic scoliosis.

Relationship between blood pressure levels and ischemic stroke, myocardial infarction, and mortality in very elderly patients taking antihypertensives: a nationwide population-based cohort study

Background

In the very elderly, “the lower the better” hypothesis has constantly been contradicted by randomized control trials and various cohort studies, but inconsistency in results led to unclear blood pressure treatment targets. This study aimed to assess the relationship between baseline blood pressure (BP) and ischemic stroke, myocardial infarction, and all-cause mortality in very elderly people treated for hypertension.

Methods

This large population-based retrospective cohort study was based on the national claims database of the Korean National Health Insurance System, which covers the entire Korean population. 374,250 participants aged ≥ 75 years taking antihypertensive agents were recruited, excluding patients with a history of previous ischemic stroke or myocardial infarction.

Results

Systolic BP (SBP) followed a J curve for ischemic stroke and a U curve for all-cause mortality, with nadir ranges of 120 to 129 mmHg and 140 to 149 mmHg, respectively. While increasing diastolic BP (DBP) generally resulted in higher HRs for ischemic stroke, HRs for myocardial infarction and all-cause mortality significantly increased only when DBP was ≥ 80 mmHg and ≥ 90 mmHg, respectively. The SBP/DBP combination analysis showed that even with SBP < 130 mmHg, higher DBP ≥ 90 mmHg had higher HRs for all three outcomes compared to the reference group (130 to 149 / < 80 mmHg).

Conclusions

There were no further benefits or even harm below certain BP levels for ischemic stroke, myocardial infarction, and all-cause mortality in very elderly hypertensive patients.

The Effects of Glucose Lowering Agents on the Secondary Prevention of Coronary Artery Disease in Patients with Type 2 Diabetes

BACKGROUND

Patients with diabetes have a higher risk of requiring repeated percutaneous coronary intervention (PCI) than non-diabetic patients. We aimed to evaluate and compare the effects of anti-diabetic drugs on the secondary prevention of myocardial infarction among type 2 diabetes mellitus patients.

METHODS

We analyzed the general health check-up dataset and claims data of the Korean National Health Insurance Service of 199,714 participants (age ≥30 years) who underwent PCIs between 2010 and 2013. Those who underwent additional PCI within 1 year of their first PCI (n=3,325) and those who died within 1 year (n=1,312) were excluded. Patients were classified according to their prescription records for glucose-lowering agents. The primary endpoint was the incidence rate of coronary revascularization.

RESULTS

A total of 35,348 patients were included in the study. Metformin significantly decreased the risk of requiring repeat PCI in all patients (adjusted hazard ratio [aHR], 0.77). In obese patients with body mass index (BMI) ≥25 kg/m2, patients treated with thiazolidinedione (TZD) exhibited a decreased risk of requiring repeat revascularization than those who were not treated with TZD (aHR, 0.77; 95% confidence interval, 0.63 to 0.95). Patients treated with metformin showed a decreased risk of requiring revascularization regardless of their BMI. Insulin, meglitinide, and alpha-glucosidase inhibitor were associated with increased risk of repeated PCI.

CONCLUSION

The risk of requiring repeat revascularization was lower in diabetic patients treated with metformin and in obese patients treated with TZD. These results suggest that physicians should choose appropriate glucose-lowering agents for the secondary prevention of coronary artery disease.

Evaluation of the association between periodontitis and risk of Parkinson's disease: a nationwide retrospective cohort study

The objective of this study was to examine the association between periodontitis and risk of incident Parkinson’s disease using large-scale cohort data on the entire population of South Korea. Health checkup data from 6,856,180 participants aged 40 and older were provided by the National Health Insurance Service of South Korea between January 1, 2009, and December 31, 2009, and the data were followed until December 31, 2017. The hazard ratio (HR) of Parkinson’s disease and 95% confidence interval (CI) were estimated using a Cox proportional hazards model adjusted for potential confounders. The incidence probability of Parkinson’s disease was positively correlated with the presence of periodontitis. The HR of Parkinson’s disease for the participants without the need of further dentist visits was 0.96 (95% CI 0.921–1.002); the HR of Parkinson’s disease increased to 1.142 (95% CI 1.094–1.193) for the individuals who needed further dentist visits. Compared to individuals without periodontitis and without metabolic syndrome, the HR of incident Parkinson’s disease gradually increased for individuals with periodontitis, with metabolic syndrome, and with both periodontitis and metabolic syndrome. People with periodontitis and metabolic syndrome had the highest HR of incident Parkinson’s disease, at 1.167 (95% CI 1.118–1.219). In conclusion, a weak association between periodontitis and Parkinson’s disease was suggested after adjusting for confounding factors from the population-based large-scale cohort of the entire South Korean population.

Association between body weight variability and incidence of Parkinson disease: A nationwide, population-based cohort study

BACKGROUND AND PURPOSE

Although body weight variability has been associated with mortality, cardiovascular disease, and dementia, the relationship between body weight variability and Parkinson disease (PD) has rarely been studied. We aimed to investigate the longitudinal association between body weight variability and PD incidence.

METHODS

A nationwide population-based, cohort study was conducted using the database from the Health Insurance Review and Assessment Service of the whole Korean population. We analyzed 2,815,135 participants (≥40 years old, mean age = 51.7 ± 8.6 years, 66.8% men) without a previous PD diagnosis. We determined individual body weight variability from baseline weight and follow-up visits. We used Cox proportional hazards regression models.

RESULTS

The highest quartile group was associated with increased PD incidence compared with the lowest quartile group after adjustment for confounding factors (hazard ratio [HR] = 1.18, 95% confidence interval [CI] = 1.08-1.29). In contrast, baseline body mass index, baseline waist circumference, and waist circumference variability were not associated with increased PD incidence. In the body weight loss group, individuals within the quartile of the highest variation in body weight showed a higher HR of PD risk than those within other quartiles (HR = 1.41, 95% CI = 1.18-1.68).

CONCLUSIONS

Body weight variability, especially weight loss, was associated with higher PD incidence. This finding has important implications for clinicians and supports the need for preventative measures and surveillance for PD in individuals with fluctuating body weight.

Dose-Dependent Effect of Smoking on Risk of Diabetes Remains after Smoking Cessation: A Nationwide Population-Based Cohort Study in Korea

BACKGROUND

This study aimed to evaluate the dose-dependent effects of smoking on risk of diabetes among those quitting smoking.

METHODS

We analyzed clinical data from a total of 5,198,792 individuals age 20 years or older who received health care check-up arranged by the national insurance program of Korea between 2009 and 2016 using the Korean National Health Insurance Service database. Cumulative smoking was estimated by pack-years. Smokers were classified into four categories according to the amount of smoking: light smokers (0.025 to 5 smoking pack-years), medium smokers (5 to 14 smoking pack-years), heavy smokers (14 to 26 smoking pack-years), and extreme smokers (more than 26 smoking pack-years).

RESULTS

During the study period, 164,335 individuals (3.2% of the total population) developed diabetes. Compared to sustained smokers, the risk of diabetes was significantly reduced in both quitters (hazard ratio [HR], 0.858; 95% confidence interval [CI], 0.838 to 0.878) and nonsmokers (HR, 0.616; 95% CI, 0.606 to 0.625) after adjustment for multiple risk factors. The risk of diabetes gradually increased with amount of smoking in both quitters and current smokers. The risk of diabetes in heavy (HR, 1.119; 95% CI, 1.057 to 1.185) and extreme smokers (HR, 1.348; 95% CI, 1.275 to 1.425) among quitters was much higher compared to light smokers among current smokers.

CONCLUSION

Smoking cessation was effective in reducing the risk of diabetes regardless of weight change. However, there was a potential dose-dependent association between smoking amount and the development of diabetes. Diabetes risk still remained in heavy and extreme smokers even after smoking cessation.

Association between metabolic syndrome and Behçet's disease: A nationwide population-based study

Metabolic syndrome (MetS) is characterized by insulin resistance, high blood pressure/sugar, dyslipidemia, and obesity. Whether MetS and its components affect the development of Behçet's disease (BD) remains unclear. This study was performed to investigate the associations between metabolic syndrome and risk of BD using nationwide population data. We conducted a retrospective cohort study of 10 505 818 Korean subjects who received health checkups in 2009-2012. Patients were classified into a MetS and its components group and were followed-up until 2016 for new-onset BD. A Cox proportional hazards model was used to assess the independent or synergistic effects of MetS and its components on the risk of incident BD. Compared to subjects without MetS components, the hazard ratio (HR) for development of BD in patients with MetS was 0.874 (95% confidence interval [CI]: 0.819-0.933) and this association was more prominent when all components of MetS were present (HR = 0.675, 95% CI = 0.571-0.798). Subjects with low high density lipoprotein (HDL) has a significantly increased risk of the development of BD (HR = 1.51, 95% CI = 1.4-1.594) compared to controls. This study showed that the incidence of Behçet's disease was reduced in subjects with MetS. Moreover, the presence of MetS components, with the exception of HDL, was negatively related to the development of BD.

The Population Prevalence, Thyroid Cancer and Mortality Risk for Turner Syndrome in South Korea Based on National Health Insurance Service (NHIS) Data

Background: In the present study, we estimated the population prevalence, cancer and mortality risk for Turner syndrome (TS) using data from National Health Insurance Service (NHIS) and Rare Diseases Registry (RDR). Methods: We collected data on subjects with TS who were registered in the RDR between 2012 and 2017. To estimate cancer and mortality risk of TS, the data of TS subjects were compared with and 1:5 age and sex matched controls. Results: In 2017, 2054 individuals with TS were identified out of the total population of 26,249,201 South Korean females and the prevalence was 7.83 per 100,000 persons. In 2017, the distributions of TS prevalence across 10 year old age groups showed 11.44 per 100,000 persons in the group under the age of 10 years, 22.43 per 100,000 persons in teenagers, 18.40 per 100,000 persons in twentieth, 10.24 per 100,000 persons in thirtieth, 4.05 per 100,000 persons in fortieth and 0.39 per 100,000 persons after fiftieth. During 5.3 years, the cancer risk in patients with TS was higher than that of age matched controls [hazard ratio (HR) = 1.813, 95% CI 1.009-3.257]. When cancer is categorized by each organs, thyroid cancer risk in patients with TS was significantly higher than that of age matched controls [hazard ratio (HR) =2.697, 95% CI 1.025-7.097]. The all cause of mortality risk of TS was higher than that of age matched controls [hazard ratio (HR) =3.421, 95% CI 1.623-7.212]. Conclusions: In South Korea, the TS population prevalence was 7.83 per 100,000 persons in 2017. The subjects with TS have higher thyroid cancer and mortality risk than healthy controls. Key words: Prevalence, Turner syndrome, thyroid cancer risk, mortality risk.

Increased Risk of Cardiovascular Disease and Mortality in Patients with Diabetes and Coexisting Depression: A Nationwide Population-Based Cohort Study

BACKGROUND

Previous studies have suggested that depression in patients with diabetes is associated with worse health outcomes. The aim of this study was to evaluate the risk of cardiovascular disease (CVD) and mortality in patients with diabetes with comorbid depression.

METHODS

We examined the general health check-up data and claim database of the Korean National Health Insurance Service (NHIS) of 2,668,615 participants with type 2 diabetes mellitus who had examinations between 2009 and 2012. As NHIS database has been established since 2002, those who had been diagnosed with depression or CVD since 2002 were excluded. The 2,228,443 participants were classified into three groups according to the claim history of depression; normal group (n=2,166,979), transient depression group (one episode of depression, n=42,124) and persistent depression group (at least two episodes of depression, n=19,340). The development of CVD and mortality were analyzed from 2009 to 2017.

RESULTS

Those with depression showed a significantly increased risk for stroke (transient depression group: hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.15 to 1.26) (persistent depression group: HR, 1.54; 95% CI, 1.46 to 1.63). Those with depression had an increased risk for myocardial infarction (transient depression group: HR, 1.25; 95% CI, 1.18 to 1.31) (persistent depression group: HR, 1.38; 95% CI, 1.29 to 1.49). The persistent depression group had an increased risk for all-cause mortality (HR, 1.66; 95% CI, 1.60 to 1.72).

CONCLUSION

Coexisting depression in patients with diabetes has a deleterious effect on the development of CVD and mortality. We suggest that more attention should be given to patients with diabetes who present with depressive symptoms.

Association of High-Density Lipoprotein Cholesterol Variability and the Risk of Developing Parkinson Disease

OBJECTIVE

To investigate the longitudinal association among high-density lipoprotein cholesterol (HDL-C) level, HDL-C variability, and the risk of developing Parkinson disease (PD).

METHODS

We conducted a nationwide, population-based cohort study. We included 382,391 patients aged ≥65 years who underwent at least 3 health examinations provided by the Korean National Health Insurance System from 2008 to 2013 and followed up until 2017. Individuals with a history of PD and missing values were excluded (n = 1,987). We assessed HDL-C variability using 3 indices, including variability independent of the mean (VIM). A multivariate-adjusted Cox proportional hazards regression analysis was performed.

RESULTS

Among the 380,404 participants, 2,733 individuals were newly diagnosed with PD during a median follow-up period of 5 years. The lowest quartile (Q1) group of baseline HDL-C and mean HDL-C was associated with increased PD incidence as compared with the highest quartile (Q4) group (adjusted hazard ratio [aHR], 1.20; 95% confidence interval [CI], 1.08-1.34; and aHR, 1.16; 95% CI, 1.04-1.30, respectively). The Q4 group of HDL-C variability (VIM) was associated with increased PD incidence compared to the Q1 group (aHR, 1.19; 95% CI, 1.06-1.33). The group with the Q1 of baseline HDL-C and with the Q4 of HDL-C variability had the highest risk of PD incidence (aHR, 1.6; 95% CI, 1.31-1.96).

CONCLUSION

Lower HDL-C level and greater HDL-C variability were associated with a higher incidence of PD.

Metabolic Syndrome and the Risk of Thyroid Cancer: A Nationwide Population-Based Cohort Study

Background: The association of metabolic syndrome and its components with the risk of thyroid cancer is unclear. Thus, we conducted a large-scale, nationwide, population-based, cohort study to investigate this relationship. Methods: We studied 9,890,917 adults without thyroid cancer from the Korean National Health Insurance health checkup database from January 1 to December 31, 2009. Individuals with at least three of the following five components were diagnosed with metabolic syndrome: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein-cholesterol levels, elevated blood pressure, and hyperglycemia. Multivariate Cox proportional hazards models were used to estimate thyroid cancer risk. Results: During the average 7.2 years of follow-up, 77,133 thyroid cancer cases were newly identified. The thyroid cancer risk was higher in the metabolic syndrome group than in the nonmetabolic syndrome group (hazard ratio [HR] 1.15 [95% confidence interval, CI 1.13-1.17]). The association between metabolic syndrome and thyroid cancer risk was significant in the obese group (HR 1.10 [CI 1.07-1.13]) and not in the nonobese group (HR 1.002 [CI 0.98-1.03]). The effect of metabolic syndrome on the risk of thyroid cancer differs according to obesity (p for interaction = 0.017). People with all five components of metabolic syndrome had a 39% higher risk than those without any components (HR 1.39 [CI 1.33-1.44]). The higher risk of thyroid cancer in people with all five components was significant in the obese group (HR 1.29 [CI 1.21-1.38]), but not in the nonobese group (HR 1.06 [CI 0.98-1.14]). There was a significant interaction between the number of metabolic syndrome components and obesity (p for interaction <0.0001). For the combined effect of obesity and metabolic syndrome on the risk of thyroid cancer, obese men with metabolic syndrome had the highest risk of thyroid cancer compared with those without (HR 1.58 [CI 1.52-1.64]), but obese women with metabolic syndrome did not. Conclusions: Metabolic syndrome was associated with an increased risk of thyroid cancer in the Korean general population. Metabolic syndrome had a more significant risk of thyroid cancer in the obese group. Metabolic syndrome and obesity were associated with a higher risk of thyroid cancer in men but not in women.

The Prevalence and Risk of Type 2 Diabetes in Adults with Disabilities in Korea

BACKGROUND

People with disabilities are at risk of secondary conditions such as diabetes. The aim of this study was to evaluate the prevalence and risk of type 2 diabetes in South Korea, especially among people with all types of disabilities.

METHODS

We conducted a cross-sectional study using data from the Korean National Health Insurance Service, with two disabilityfree controls matched for each participant with disabilities by age and sex. Information regarding the type, severity and grade of disabilities was obtained based on the National Disability Registry. Diagnosis of type 2 diabetes was defined according to the following criteria: presence of International Classification of Diseases, Tenth Revision, Clinical Modification codes E11, E12, E13, or E14 and claims for at least one oral anti-diabetic agent or insulin at baseline, or fasting glucose level ≥126 mg/dL.

RESULTS

We included 1,297,806 participants with disabilities and 2,943,719 control. Out of 4,241,525 participants, 841,990 (19.9%) were diagnosed with diabetes. The prevalence of diabetes was higher in the disability group compared with individuals without disabilities (23.1% vs. 18.4%). The odds of having diabetes was higher in the disability group compared with the control group (adjusted odds ratio, 1.34; 95% confidence interval, 1.33 to 1.34). The results showed higher prevalence of diabetes in the mildly disabled group (23.2%) than in the severely disabled group (22.7%).

CONCLUSION

The prevalence and risk of diabetes were higher in people with disabilities compared with the general population. Physicians and public health authorities should focus on people with disabilities for proper diabetes management.

Association Between Glycemic Status and the Risk of Parkinson Disease: A Nationwide Population-Based Study

OBJECTIVE

Previous studies have suggested that diabetes increases the risk of Parkinson disease (PD); however, this has not been conclusively established. We analyzed the risk of PD based on baseline glucose tolerance status in a large-scale cohort representative of the general Korean population.

RESEARCH DESIGN AND METHODS

This analysis was performed in a cohort of 15,168,021 adults aged ≥40 years who underwent health checkups under the National Health Insurance Service between January 2009 and December 2010. The clinical course of subjects was monitored until December 2016. Subjects were classified into the following groups: no diabetes, impaired fasting glucose (IFG), diabetes duration <5 years, and diabetes duration ≥5 years. We analyzed the adjusted hazard ratio of PD for each group.

RESULTS

During the observation period of 49,076,148.74 person-years, PD occurred in 31,577 patients. Compared with the nondiabetes group, the adjusted hazard ratio was 1.038 (95% CI, 1.009-1.067) in the IFG group, 1.185 (95% CI, 1.143-1.229) in the diabetes duration <5 years group, and 1.618 (95% CI, 1.566-1.672) in the diabetes duration ≥5 years group. These results were consistent with those of the subgroup analysis, and the presence of diabetes further increased the risk of PD regardless of comorbidities such as cardiovascular, cerebrovascular, and chronic kidney diseases.

CONCLUSIONS

This population-based cohort study suggests that diabetes is an independent risk factor for PD.

The Population Prevalence, Associations of Congenital Heart Defect and Mortality Risk for Down's Syndrome in South Korea Based on National Health Insurance Service (NHIS) Data

Background

In the present study, we estimated the population prevalence, associations of congenital heart defect (CHD) and mortality risk for DS using data from National Health Insurance Service (NHIS) and Rare Diseases Registry (RDR).

Methods

We collected data on subjects with DS who were registered in the RDR between 2010 and 2015. To estimate associations of CHD and mortality risk of DS, the data of DS subjects were compared with 1:5 age- and sex-matched controls.

Results

In 2015, 2077 individuals with DS were identified out of the total population of 51,574,044 South Koreans and the prevalence was 4.03 per 100,000 persons. The trend of DS population prevalence across 10-year-old intervals showed a peak in the group under the age of 10 years (26.0 per 100,000 persons) and then declined sharply after the age of 20 years (0.98 per 100,000 persons at 30-39 years of age). In subjects with DS, the frequencies of atrial septal defect [odds ratios (OR) =65.9; 95% CI, 84.1-99.1], ventricular septal defect (OR = 88.1, 95% CI, 57.9-134.1), patent ductus arteriosus (OR = 56.9, 95% CI, 40.1-80.8), tetralogy of fallot (OR = 42.1, 95% CI, 19.3-92.3), or atrioventricular septal defect (OR = 510.0, 95% CI, 126.7-999.0) were higher than those of age- and sex-matched controls. The risk of death in patients with DS was significantly higher than that of age- and sex-matched controls [hazard ratio (HR) =41.7, 95% CI 20.0-87.0].

Conclusion

In South Korea, the DS population prevalence was 4.03 per 100,000 persons in 2015. The subjects with DS were more likely to accompany CHD and have higher mortality risk than healthy controls.

Underweight Increases the Risk of End-Stage Renal Diseases for Type 2 Diabetes in Korean Population: Data From the National Health Insurance Service Health Checkups 2009-2017

OBJECTIVE

There is a controversy over the association between obesity and end-stage renal disease (ESRD) in people with or without type 2 diabetes; therefore, we examined the effect of BMI on the risk of ESRD according to glycemic status in the Korean population.

RESEARCH DESIGN AND METHODS

The study monitored 9,969,848 participants who underwent a National Health Insurance Service health checkup in 2009 from baseline to the date of diagnosis of ESRD during a follow-up period of ∼8.2 years. Obesity was categorized by World Health Organization recommendations for Asian populations, and glycemic status was categorized into the following five groups: normal, impaired fasting glucose (IFG), newly diagnosed diabetes, diabetes <5 years, and diabetes ≥5 years.

RESULTS

Underweight was associated with a higher risk of ESRD in all participants after adjustment for all covariates. In the groups with IFG, newly diagnosed type 2 diabetes, diabetes duration <5 years, and diabetes ≥5 years, the hazard ratio (HR) of the underweight group increased with worsening glycemic status (HR 1.431 for IFG, 2.114 for newly diagnosed diabetes, 4.351 for diabetes <5 years, and 6.397 for diabetes ≥5 years), using normal weight with normal fasting glucose as a reference. The adjusted HRs for ESRD were also the highest in the sustained underweight group regardless of the presence of type 2 diabetes (HR 1.606 for nondiabetes and 2.14 for diabetes).

CONCLUSIONS

Underweight showed more increased HR of ESRD according to glycemic status and diabetes duration in the Korean population. These associations also persisted in the group with sustained BMI during the study period.

Dipstick proteinuria and cancer incidence: a nationwide population-based study

BACKGROUND

The association between proteinuria and malignancy has been frequently reported, but the issue is matter of controversy. Thus, in order to shed light on the association, we evaluated proteinuria as a risk factor for malignancy using the dataset from the Korean National Health Insurance System (NHIS).

METHODS

The subjects had undergone a medical examination in 2009 (index year) among the entire Korean adult population. From a pool of 10,505,818 participants, we excluded subjects who were younger than 19 years (15,327), had a previous diagnosis of cancer (152,095), had missing data for at least one variable (544,508), and were diagnosed with cancer within 1 year from the index year (79,501). Proteinuria was examined by a single dipstick urinalysis.

RESULTS

A total of 9,714,387 subjects were included in this study and tracked until December 31, 2017. The participants were divided into three groups; no (95.2%), trace (2.3%), and overt (2.5%) proteinuria. Over the duration of this study, we observed that overt proteinuria was associated with an increased risk of cancer development (all cancers) (adjusted HR 1.154, 95% CI 1.134-1.173) and the long-term risk of cancer incidence increased proportionally according to the changes in proteinuria over a four-year period.

LIMITATIONS

Our study population consisted of Korean adults. Therefore, the results of this study may not be generalized to other ethnicities.

CONCLUSIONS

We found a significant relationship between proteinuria and the risk of overall and site-specific cancer development. Further studies are needed to find an explanation of these findings.

Increased Mortality Burden in Young Asian Subjects with Dysglycemia and Comorbidities

BACKGROUND

High blood glucose level has a linear relationship with all-cause mortality. However, the influence of glycemic abnormality on mortality differs by age group. We aimed to analyze all-cause mortality according to glycemic status, age groups, and comorbidities using a national health database.

METHODS

The 6,330,369 participants who underwent Korean National Health Screening in 2009 were followed up until 2016, with a median follow-up of 7.3 years. All-cause mortality rates were analyzed according to glycemic status (normoglycemia, impaired fasting glucose [IFG], newly diagnosed diabetes, diabetes duration <5 years, diabetes duration ≥5 years), age groups (20-39, 40-65, and ≥65 years), and comorbidities using the Korean National Health Insurance System database.

RESULTS

At baseline, 712,901 (11.3%) subjects had diabetes. Compared with subjects without diabetes, those with diabetes at baseline showed increased mortality risk after adjustment for multiple risk factors (hazard ratio [HR] 1.613; 95% confidence interval [CI] 1.598,1.629), and those with IFG showed a significantly increased mortality risk compared with normoglycemic subjects (HR 1.053; 95% CI 1.042,1.064). Mortality risk associated with glycemic status decreased gradually from younger to older age groups and was consistently higher in those with diabetes with coronary heart disease, ischemic stroke or decreased renal function than those without comorbidities.

CONCLUSION

Compared with normoglycemic subjects, subjects with diabetes and IFG had an increased mortality risk and the mortality risk was higher in the younger age group than in the older age group. The presence of diabetes and comorbid diseases synergistically increased mortality risk.

Association between weight change over a period of 4 years and mortality in Korean older adults

AIM

This study aimed to evaluate the association between weight change and mortality in Korean older adults.

METHODS

We collected data pertaining to National Screening Program participants aged ≥65 years from the Korean National Health Insurance Corporation records during 2005-2011. To this data, we included mortality data, such as the date of death, of these patients (up to and including 2017) from Statistics Korea. We defined weight change as a difference in bodyweight measured in the National Screening Program over a period of 4 years. Cox proportional hazards models were used to evaluate the association between weight change and mortality.

RESULTS

The study population consisted of 1 100 256 participants, and a total of 46 415 deaths were observed during a mean follow-up period of 3.2 ± 0.8 years (maximum 5.0 years). For 3 531 585 person-year follow up, the mortality rate for stable weight was 10.79 per 1000 person-years (PY). Weight loss increased the mortality rate by 68%, whereas weight gain increased the rate by 10% compared with stable weight (weight loss: mortality rate 20.28 per 1000 PY, adjusted hazard ratio 1.68, 95% confidence interval 1.65-1.72; weight gain: mortality rate 12.86 per 1000 PY, adjusted hazard ratio 1.10, 95% confidence interval 1.07-1.13). However, in subgroup analysis, for participants who were underweight at baseline, current cigarette smokers or heavy alcohol drinkers, weight gain did not increase the mortality rate.

CONCLUSIONS

In Korean older adults, regardless of the risk factors, both weight loss and weight gain increased the mortality rate compared with stable weight. Geriatr Gerontol Int 2020; 20: 474-481.

Underweight increases the risk of primary open-angle glaucoma in diabetes patients: A Korean nationwide cohort study

The impact of underweight on the risk of developing primary open-angle glaucoma (POAG) is not known, although the association between obesity and POAG has been well studied. We evaluated the risk of POAG among underweight patients by studying a nationwide cohort sample in South Korea.We analyzed data from the Korean National Health Insurance Research Database collected between 2009 and 2012 for 17,000,636 patients aged 40 years or older. Newly diagnosed POAG in the cohort was identified using claims data between 2009 and 2015.A total of 442,829 individuals (2.60%) were classified as underweight (body mass index [BMI] < 18.5 kg/m). During the follow-up period, 435,756 (2.56%) subjects were newly diagnosed with POAG. Multivariate analyses revealed that underweight was significantly related to an increased risk of future POAG development, by 9.8% and 27.8% in individuals with and without diabetes, respectively. There was a reverse J-shaped relationship between BMI and risk of POAG in the normal, impaired glucose tolerance, and diabetes groups; especially, this relationship was most notable in participants with diabetes.Patients who were underweight exhibited a significantly higher prospective risk of POAG, even after adjusting for confounding factors.

Association between Parent's Metabolic Syndrome and 12- to18-Year-Old Offspring's Overweight: Results from the Korea National Health and Nutrition Examination Survey (K-NHANES) 2009-2016

BACKGROUND

Little information is available on the association between parents' metabolic syndrome (MetS) and adolescent offspring's obesity in Korea. The aim of our study is to determine the association between parent's metabolic syndrome and offspring's obesity.

METHODS

The study data were obtained from the Korean National Health and Nutrition Examination Survey conducted during 2009-2016. In the present study, 3140 adolescents aged 12 to 18 years, their paternal pairs (PP, fathers = 2244), and maternal pairs (MP, mothers = 3022) were analyzed. Of these 3140 adolescents, 2637 had normal weight {age- and sex-specific body mass index (BMI) under the 85^th percentile}, whereas 467 were overweight (age- and sex-specific BMI over the 85^th percentile).

RESULTS

Offspring's overweight and central obesity were associated with all components of the PP's metabolic risk factors, including central obesity (p < 0.001), systolic (p < 0.001) and diastolic blood pressure (p < 0.001), glucose intolerance (p < 0.001), and triglyceride (p < 0.002) and high-density lipoprotein levels (p=0.049). In addition, offspring's overweight and central obesity were also associated with the metabolic risk factors of MP, including central obesity (p < 0.001), systolic (p < 0.001) and diastolic blood pressure (p < 0.001), glucose intolerance (p < 0.001), and triglyceride levels (p < 0.001). In multivariate logistic regression analysis, offspring's overweight was significantly and positively associated with parental central obesity (PP, adjusted odds ratio (OR) = 1.593; 95% confidence interval (CI): 1.192-2.128; MP, adjusted OR = 2.221, 95% CI: 1.755-2.812) and parental metabolic syndrome (PP, adjusted OR = 2.032; 95% CI: 1.451-2.846; MP, adjusted OR = 2.972, 95% CI: 2.239-3.964). As the number of parental metabolic risk factors increased, offspring's risk for overweight and central obesity increased (p for trends < 0.001).

CONCLUSION

Parental metabolic syndrome was associated with obesity in 12- to 18-year-old offspring in Korea.

Trends in the incidence and prevalence of Parkinson's disease in Korea: a nationwide, population-based study

BACKGROUND

The lack of adequate and detailed epidemiological data of Parkinson's disease (PD), especially in Asia, is a barrier to future disease burdens and the prospect of effective public health plans. This study aimed to investigate temporal trends in the incidence and prevalence of PD in South Korea from 2010 to 2015, based on uniform diagnostic criteria.

METHODS

This study examined all PD patients registered in a South Korean national registry database of more than 50 million individuals. We analyzed the incidence and prevalence of PD according to age, gender, and region.

RESULTS

The annual incidence of PD was between 22.4-27.8 cases per 100,000 individuals. During the 6-year study period, there were 73,726 new PD patients, 42.3% of whom were men. The standardized incidence of PD increased over time in men but remained constant in women until 2013 but began to increase in 2014. The female-to-male ratio in the incidence of PD was 1.4:1 while the female-to-male ratio in the prevalence of PD was 1.6:1. The age- and gender-standardized prevalence of PD increased from 115.9 cases per 100,000 individuals in 2010 to 139.8 cases per 100,000 individuals in 2015. From 2014, the incidence and prevalence of PD peaked in individuals aged between 80 and 89 years in both men and women. Regional analysis also showed an increased prevalence of PD in all regions of Korea.

CONCLUSIONS

The incidence and prevalence of PD in Korea were higher in women and increased gradually from 2010 to 2015. The findings may contribute to epidemiological studies of PD in Asia, and may provide clues on risk factors for PD.

Metabolic syndrome is associated with an increased risk of psoriasis: A nationwide population-based study

BACKGROUND

Psoriasis is a chronic inflammatory skin disease characterized by an abnormal T-cell-mediated immune response, and is associated with metabolic syndrome (MetS) and components thereof. However, few prospective studies have investigated the associations between MetS and its components, on the one hand, and the risk of psoriasis, on the other. Therefore, we investigated the association between the presence of MetS and its components and the prospective risk of psoriasis development.

METHODS

In total, 9,718,591 adults (2,595,878 in the MetS group and 7,122,713 in the comparison group) were evaluated using data from the Korean National Health Insurance Service (2009 to 2017).

RESULTS

MetS was positively associated with an increased risk of psoriasis over an 8-year follow-up period after adjusting for age, sex, smoking status, alcohol consumption, physical activity, household income, and body mass index (hazard ratio 1.05, 95% confidence interval 1.04-1.06). The risk of psoriasis tended to increase as the number of MetS components increased, and this trend was significant in obese subjects (P for trend <0.001).

CONCLUSION

Psoriasis was significantly and positively associated with MetS and several components thereof; MetS severity and obesity affected these associations over 8 years of follow-up, suggesting that MetS is a risk factor for the development of psoriasis.

Metoclopramide and Levosulpiride Use and Subsequent Levodopa Prescription in the Korean Elderly: The Prescribing Cascade

The aim of this study was to investigate the prescribing cascade phenomenon of dopaminergic drugs such as levodopa in the management of gastroprokinetic drugs induced parkinsonism. Based on the Korea National Health Insurance Service (NHIS)-Senior Cohort Database, we analyzed patients aged ≥65 years, between 2009 and 2013, who obtained new prescriptions for levodopa through the NHIS during this period. Those who were prescribed levodopa from 2002 to 2008 were excluded, only patients who were prescribed metoclopramide and levosulpiride within 90 days of receiving the levodopa prescription were included. Those who did not receive levodopa were used as a control group for 1:3 age and sex matching. We assessed 1824 and 1197 levodopa cases for metoclopramide and levosulpiride use, respectively. The matched controls for each levodopa case were 5472 and 3591, respectively. We used conditional logistic regression to determine the odds ratio (OR) for initiation of levodopa therapy in patients using metoclopramide and levosulpiride, relative to nonusers, after adjusting for age, sex, and exposure to antipsychotic medication. Both metoclopramide (OR = 3.04; 95% confidence interval, CI, 2.46-3.77) and levosulpiride (OR = 3.32; 95% CI, 2.56-4.3) users were three times more likely to begin using medication containing levodopa, compared to nonusers. Metoclopramide and levosulpiride were frequently prescribed within 90 days of receiving a prescription for levodopa. Before prescribing levodopa, it should be considered whether the adverse event is actually a side effect caused by metoclopramide and levosulpiride.

Factors associated with quality of life in patients with depression: A nationwide population-based study

Background

Depression, one of the most costly and common mental disorders, is reported to be associated with lower quality of life (QoL) in several studies. Improved understanding of the associated factors with QoL is necessary to optimize long-term outcomes and reduce disability in patients with depression. Therefore, the aim of this study was to identify factors that are associated with lower QoL among patients with depression.

Methods

The study was based on the Korea National Health and Nutrition Examination Survey, a cross-sectional health examination, years 2008 to 2014. The final analyzed sample consisted of a total of 1,502 study subjects who had been diagnosed by clinicians as having depression. A multivariate logistic regression model was performed to exam the association between the clinical characteristics (age, sex, demographic and health-related characteristics) and QoL. Analysis of covariance was also used to analyze EQ-5D according to mental health.

Results

Older age, lower level of education, lower income, worse subjective perception of health, unemployment, obesity and mental health struggles were found to be significantly associated with low QoL in depressive individuals after adjustment for multiple covariates.

Conclusions

This study has outlined grounding data in identifying patients who are at risk of QoL impairment. Policy makers should direct their interests to these individuals and provide appropriate management.

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.

Cancer risk in patients with Parkinson's disease in South Korea: A nationwide, population-based cohort study

INTRODUCTION

The association between Parkinson's disease (PD) and cancer development is controversial, especially in Asia. Therefore, we conducted a nationwide population-based cohort study to assess the overall cancer risk and risk for specific cancers in patients with PD in Korea.

METHODS

Using data from the Korean National Health Insurance Database, we analysed 52,009 patients diagnosed with PD between 2010 and 2015 and 260,045 individuals without PD. Patients previously diagnosed with cancer were excluded. The age- and sex-matched cohorts were followed up until 2016 for cancer development. Cox proportional hazards regression models were used to evaluate the relationship between PD and cancer.

RESULTS

Patients with PD had a lower overall cancer risk (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.74-0.82) after adjustment for multiple covariates during 2,022,852.6 person-years of follow-up. Patients with PD showed significantly lower risk of laryngeal cancer (HR, 0.45; 95% CI, 0.21-0.84), gastric cancer (HR, 0.72; 95% CI, 0.63-0.82), colorectal cancer (HR, 0.675; 95% CI, 0.60-0.76), liver cancer (HR, 0.80; 95% CI, 0.67-0.95), pancreatic cancer (HR, 0.75; 95% CI, 0.62-0.91), lung cancer (HR, 0.73; 95% CI, 0.63-0.84), leukaemia (HR, 0.49; 95% CI, 0.24-0.89), uterine cervical cancer (HR, 0.64; 95% CI, 0.40-0.99) and prostate cancer (HR, 0.78; 95% CI, 0.66-0.91).

CONCLUSION

This nationwide population-based cohort study revealed that patients with PD had lower overall cancer risk and lower risk of specific cancers. Contrary to the results of the recent Asian study, this large cohort study revealed that patients with PD were less likely to develop cancer than those without PD in Korea. Our results were consistent with those of previous Western studies, despite differences in ethnicity and environment.

Anemia and health-related quality of life in South Korea: data from the Korean national health and nutrition examination survey 2008-2016

BACKGROUND

Anemia is associated with impaired quality of life (QoL). We examined the relationship between anemia and QoL in the Korean population using the EuroQol five-dimensional (EQ-5D) questionnaire.

METHODS

Data of 30,526 subjects were included from the Korean National Health and Nutrition Examination Survey (2008-2016). The QoL was assessed using three-levels of the EQ-5D questionnaire (G1, G2, and G3). Analysis of variance was used to compare the prevalence of anemia according to the three levels of health status in each of the five dimensions of EQ-5D. Multiple linear regression analysis was used to evaluate the association between hemoglobin level and QoL, and multivariable logistic regression analysis was used to evaluate the odds ratios (ORs) and 95% confidence intervals (CIs) for low levels of each of the five dimensions of EQ-5D.

RESULTS

As the level of EQ-5D was worse (from G1 to G3), the prevalence of anemia increased (p for trend < 0.001). Hemoglobin level and EQ-5D showed positive association after adjusting for all covariates such as age, sex, smoking, alcohol drinking, exercise, education, income, marital status, urban living, diabetes mellitus, hypertension, hypercholesterolemia, chronic kidney disease, total calorie intake, and protein intake. Subjects with anemia had increased ORs for low levels (G2 + G3) of each dimension of EQ-5D compared to subjects without anemia. ORs and 95% CIs for mobility, self-care, and usual activities were 1.208(1.078, 1.353), 1.161(0.98, 1.376), and 1.331(1.173, 1.51), respectively, after adjusting for all covariates. Pain/discomfort and anxiety/depression were not associated with increased ORs for low levels of EQ-5D.

CONCLUSIONS

In South Korea, low QoL was associated with anemia, particularly in the mobility, self-care, and usual activities dimensions of EQ-5D.

Maintenance of body weight is an important determinant for the risk of ischemic stroke: A nationwide population-based cohort study

Background

Overweight is known as a risk factor for ischemic stroke. However, the effect of weight change on the development of ischemic stroke remains controversial. We investigated the relationship between weight change and the risk of ischemic stroke using a nationwide population-based cohort.

Methods

Our study enrolled 11,084,683 participants (Mean age 49.7±13.5 years, range 20–114 years) in the Korean National Health Screening Program from 2009 to 2012. Weight change was calculated using the difference between the baseline weight and the weight at health screening four years prior to the baseline. The occurrence of newly-diagnosed ischemic stroke was observed until the end of 2015. We categorized the study population according to weight change and performed multivariable analysis to compare the risk.

Results

Ischemic stroke was newly diagnosed in 113,591 subjects. The crude incidence rates of ischemic stroke per 1000 person-years according to the change in body weight were 3.059, 1.906, and 1.491 in the <-5%, ±5%, and ≥+5% groups, respectively. After adjusting all variables, the hazard ratio (HR) of ischemic stroke was higher in subjects who underwent weight loss (HR 1.152) or weight gain (HR 1.087) than in those who maintained their weight. When analyzed by eight groups of 5% intervals, the risk showed a U-shaped curve with those who maintained their weight showing the lowest risk.

Conclusions

The risk of ischemic stroke was gradually increased in those who lost or gained more than 5% of their weight over four years, after adjusting for confounders. We should be aware of the increased risk of ischemic stroke in people who undergo weight change and should identify and manage the cause of weight change.

Association between statin treatment and new-onset diabetes mellitus: a population based case-control study

BACKGROUND

Several studies suggest that statin may increase the risk of new-onset diabetes mellitus (NODM). This study aimed to evaluate the association between the duration and recent use of statin, and the risk of NODM, based on population-based data sets.

METHODS

We used the South Korean National Health Insurance Service National Sample Cohort database for this nationwide case-control study. Of the 1 million participants, 6417 participants with NODM in 2012-2013 and 32,085 controls without diabetes (1:5 propensity score matched with age, sex, index year, and year of diabetes diagnosis) were included. In these patients, we examined the statin prescription record for 3 years preceding the outcome. We used conditional logistic regression to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

After adjustment of covariates, there were no significant differences in the risk of NODM when analyzed according to cumulative use days. The risk of NODM was increased only in the short-term and recent user group (OR 1.48, 95% CI 1.21 to 1.82) whose cumulative prescription days are less than 6 months and whose last prescription is within 6 months of diagnosis.

CONCLUSIONS

The risk of NODM was not associated with an increase in the cumulative duration of statin use or with non-recent use. Only recent short-term use of statin was associated with an increased risk of NODM. Diabetes screening are warranted during initial statin therapy.

Actinic keratosis and diabetes complications: A nationwide population-based study in South Korea (2009-2015)

AIM

As the associations between actinic keratosis (AK) and diabetes complications in patients with diabetes mellitus (DM) have never been investigated, this study aimed to evaluate any such associations in patients with DM.

METHODS

This retrospective cohort study analyzed clinical data for DM patients aged>40 years who had undergone the health examination recommended by the South Korea National Health Insurance Program between 2009 and 2012 (n=2,056,580). All of these patients were classified according to the presence of diabetic retinopathy (DR), end-stage renal disease (ESRD) and history of DVD; myocardial infarction, stroke, transient ischaemic attacks. Newly diagnosed AK was identified using claims data from baseline to the date of diagnosis or 31 December 2015, whichever came first.

RESULTS

Of the 2,056,580 patients with DM, 6404 (0.31%) developed AK. Those patients in the DR, ESRD and CVD groups were more likely to be diagnosed with AK (P<0.001, by log-rank test). After adjusting for age and gender, the risks for AK were significantly higher in the DR, ESRD and CVD groups: HR (95% CI): 1.29 (1.21-1.39), HR: 4.24 (3.28-5.47) and HR: 1.22 (1.13-1.31), respectively.

CONCLUSION

This study has revealed that the incidence of AK is higher in diabetes patients with ocular, renal and cardiovascular complications.

Height Loss Was Associated With Osteoporosis in Korean Elderly Men, Not in Women: The Korea National Health and Nutrition Examination Survey 2008-2010

The degree of height loss varies among individuals, and excessive height loss can be a vertebral fracture or bone loss manifestation. The objective of this study was to examine the relationships between height loss and bone mineral density (BMD) and to assess the prevalence of osteoporosis according to the height loss quartiles. Data from the Korea National Health and Nutrition Examination Survey were analyzed. A total of 2799 participants more than 60 years old were included and subdivided into quartiles according to height loss (Q1-Q4). Height loss was calculated with the difference between the self-reported maximum adult height and the actual measured height. BMD was measured by dual-energy X-ray absorptiometry at the total femur (TF), femoral neck, and lumbar spine. Multivariable linear and logistic regression analyses were conducted to study the height loss-BMD and the height loss-osteoporosis prevalence relationships, respectively. After adjustments for all covariates, height loss was negatively associated with BMD at all the 3 sites (TF and lumbar spine, p < 0.001; femoral neck, p = 0.002) in men, but only at TF (p = 0.008) in women. Men with Q4 height loss had an increased prevalence of osteoporosis compared with those with Q1 (odds ratio = 2.092 and 95% confidence interval = 1.076-4.068). In women, the prevalence of osteoporosis was not associated with height loss. In conclusion, Q4 height loss in elderly men was associated with the increased prevalence of osteoporosis in Korea.

Cancer risk in 892 089 patients with psoriasis in Korea: A nationwide population-based cohort study

The relationship between psoriasis and cancer has not yet been established. The aim of this study was to evaluate the association of psoriasis with certain cancers using national statistics. All patients with psoriasis (n = 892 089; 51.7% male) and age- and sex-matched control subjects (n = 4 460 445) at a 5:1 ratio were enrolled using data from the National Health Insurance Service between 2007 and 2014 in Korea. In psoriatic subjects, overall cancer risk was higher than for subjects without psoriasis after adjusting for income level, diabetes, hypertension, dyslipidemia and place of residence (hazard ratio, 1.065; 95% CI, 1.049-1.081). The risk of cancer increased in the following order: prostate, thyroid, liver, ovarian, lung, leukemia, skin, multiple myeloma, lymphoma and testicular. The severity and sex of psoriatic patients also had different cancer risks. In psoriatic patients, a slightly increased risk for specific malignant neoplasms was shown. Therefore, periodic screening for cancer risk is recommended in patients with psoriasis.

Multiple birth rates of Korea and fetal/neonatal/infant mortality in multiple gestation

Objective

This study was conducted to analyze recent trends of multiple birth rates (MBR) and fetal/neonatal/infant mortalities according to the number of gestations in Korea.

Methods

Data from 2009 to 2015 of live births, infant deaths and stillbirths were obtained from the Korean Vital Statistics. Neonatal mortality rate (NMR), infant mortality rate (IMR), and fetal mortality rate (FMR) in singleton, twin and triplet pregnancies were analyzed according to gestational period (GP; ≤ 23, 24–27, 28–31, and 32–36 weeks).

Results

From 2009 to 2015, twin and triplet birth rates increased 34.5% and 154.3%, respectively. In twin births, NMR and FMR have been decreased significantly (from 10.92 to 8.62, p = 0.034 and from 41.00 to 30.55, p< 0.001, respectively), but IMR did not show significant decrease. There was no significant change of NMR, IMR, and FMR, in triplet births. Overall, in singleton, twin, and triplet births, NMR was 1.26 ± 0.09, 10.6 ± 1.12, and 34.32 ± 11.72, respectively, and IMR was 2.38 ± 0.26, 14.52 ± 1.38, and 41.13 ± 12.2, respectively. FMRs were 12 ± 1.73, 35.99 ± 3.55, and 88.85 ± 16.55, respectively, in singleton, twin, and triplet pregnancies. In spite of decreasing trends in overall mortalities, the odds ratios of NMRs and IMRs in 2015 were approximately 9-fold and 6-fold higher, respectively, in twin births, and approximately 37-fold and 20-fold higher, respectively, in triplet births, than those in singleton births. There were no significant differences in odds ratios of NMRs and IMRs at GP 32–36 among single, twin, and triplet births, although the odds ratios of FMR at GP 32–36 in triplet gestation was significantly higher than those in singleton and twin gestation.

Conclusion

Neonatal/infant mortality in multiple births is still significantly high, which is mainly related with preterm birth. Close fetal monitoring is needed to prevent fetal death in triplet pregnancies, after 32 gestational weeks.

Dipstick proteinuria predicts all-cause mortality in general population: A study of 17 million Korean adults

Objective

A quantitative basis for the use of dipstick urinalysis for risk assessment of all-cause mortality is scarce. Therefore, we investigated the association between dipstick proteinuria and all-cause mortality in a general population and evaluated the effect of confounders on this association.

Methods

The study population included 17,342,956 adults who underwent health examinations between 2005 and 2008 under the National Health Insurance System. Proteinuria was determined using a single dipstick urinalysis, and the primary outcome of this study was all-cause mortality. The prognostic impact of proteinuria was assessed by constructing a multivariable Cox model.

Results

The mean age of the study population (53.24% male) was 46.06 years; 724,681 deaths from all causes occurred over a median follow-up period of 9.34 years (interquartile range 8.17–10.16), and the maximum follow-up was 12.12 years. After full adjustment for covariates, a higher level of dipstick proteinuria indicated a higher risk of all-cause death [Hazard ratios (95% confidence intervals); 1.22 (1.20–1.24), 1.47 (1.45–1.49), 1.81 (1.77–1.84), 2.32 (2.24–2.41), 2.74 (2.54–2.96); trace to 4+, respectively], and various subgroup analyses did not affect the main outcome for the total population. ≥1+ proteinuria in the group without metabolic diseases (hypertension, diabetes, dyslipidemia, or obesity) resulted in higher hazard ratios than those in the group with metabolic diseases and negative or trace proteinuria.

Conclusions

Our study showed a strong association between dipstick proteinuria and all-cause mortality in this nationwide population-based cohort in South Korea.

Cancer risk by the subtype of alopecia

The cancer risk in patients with alopecia areata (AA) or alopecia totalis (AT)/alopecia universalis (AU) remains unknown. In this study, national statistical data were used to study the association between these forms of alopecia and the risk of cancer. We enrolled 668,604 patients who were treated for alopecia from 2007 to 2014, and age- and sex-matched control subjects. AA and AT/AU patients had slightly higher overall cancer risks (hazard ratio (HR), 1.043; 95% confidence interval (CI), 1.022-1.065 and HR, 1.07; 95% CI, 1.013-1.129, respectively) than controls, after adjusting for confounding factors. The risks of oral cavity, esophagus, liver, biliary tract, pancreas, larynx, lung, kidney, breast, cervix, ovary, uterus, testis, nerve, and skin cancers; and lymphoma, multiple myeloma, and leukemia, were not increased in alopecia patients. In AA or AT/AU patients, the only increased risk was that of thyroid cancer. In AA patients alone, the risks of bladder and prostate cancers were increased. Thus, the cancer risks varied by the alopecia subtype. Careful monitoring is needed to explore if the actual risks of thyroid, bladder, and prostate cancers are increased in alopecia patients.

Metabolic risk factors in Korean adolescents with severe obesity: Results from the Korea National Health and Nutrition Examination Surveys (K-NHANES) 2007-2014

AIMS

To investigate the metabolic risk factors according to the degree of obesity in Korean adolescents.

METHODS

Among 7197 subjects aged 10-18 years who participated in the 2007-2014 K-NHANES, 1326 adolescents (M = 744, F = 582) with age and sex specific body mass index (BMI) ≥85th percentile were included. These adolescents with obesity were classified as: overweight, obesity, severe obesity, and extreme severe obesity. For assessing central obesity, the subjects were further-classified as: normal waist obese, abdominal obesity I, abdominal obesity II and abdominal obesity III.

RESULTS

The prevalence of overweight, obesity, severe obesity and extreme severe obesity were 5.6%, 6.2%, 5.9% and 0.9% in Korean adolescents. With increasing levels of obese category, the incidence of metabolic risk factors such as HDL-C < 40 mg/dL or <50 mg/dL in girls older than 16 years-old (20.2%, 18.5%, 34.4%, 43.6%, P < .0001), TG ≥ 150 mg/dL (15.3%, 16.7%, 26.5%, 30.9%, P < .003), HbA1C ≥ 5.8% (12.8%, 13.5%, 21.9%, 42.2%, P < .006), SBP ≥ 130 mg/dL (3.5%, 6.4%, 8.1%, 19.5%, P < .003) significantly increased. With increasing levels of central obese category, the incidence of metabolic risk factors such as HDL-C < 40 mg/dL or <50 mg/dL in girls older than 16 years-old (20.2%, 26.2%, 37.9%, 35.7%, P < .0007), TG ≥ 150 mg/dL (16.1%, 21.2%, 25.8%, 29.8%, P < .004), glucose ≥ 100 mg/dL (7.7%, 7.3%, 11.7%, 17.4%, P < .009) and SBP ≥ 130 mg/dL (5.1%, 7.1%, 3.0%, 13.9%, P < .002) significantly increased.

CONCLUSION

Adolescents with severe obesity have more metabolic risk factors compared to adolescents with less severe degree of obesity.

Prevalence of Obesity and Incidence of Obesity-Related Comorbidities in Koreans Based on National Health Insurance Service Health Checkup Data 2006-2015

Background

The prevalence of obesity and related comorbidities is increasing worldwide, including in Korea. The Korean Society for the Study of Obesity released the Obesity Fact Sheet 2017 to address this problem in the Korean population.

Methods

Data from the National Health Insurance Service Health Checkup database from 2006 to 2015 were standardized by age and sex using the 2010 Census. The definition of obesity was a body mass index (BMI) ≥25 kg/m², and that of abdominal obesity was a waist circumference ≥90 cm in men and ≥85 cm in women. Multivariate adjusted Cox regression analysis was conducted, and hazard ratios (HRs) with 95% confidence intervals were calculated for comorbidities.

Results

From 2009 to 2015, the prevalence of obesity increased from 29.7% to 32.4%, and that of abdominal obesity increased from 18.4% to 20.8%. Obesity with abdominal obesity also increased from 15.1% to 17.7%. Between 2014 and 2015, the prevalence of obesity increased until 30-40 years of age, but decreased from 40-50 years of age in men. In women, it increased until the mid-70s, and decreased thereafter. Abdominal obesity increased from 20-30 years of age to 70-80 years of age, but decreased thereafter. The HRs for type 2 diabetes mellitus, hypertension, dyslipidemia, myocardial infarction, and ischemic stroke were elevated in subjects with abdominal obesity, and their incidence increased as the BMI increased, but slowed down at BMI ≥35 kg/m².

Conclusion

Based on the Obesity Fact Sheet 2017, strategies for reducing the prevalence of obesity and abdominal obesity are essential.

Oral health behavior as a risk factor for high urinary sodium among Korean women

BACKGROUND AND OBJECTIVES

The purpose of the present study was to investigate the association between urinary sodium, urinary sodium/creatinine, and urinary sodium/urine specific gravity and oral health behavior using nationally representative data.

METHODS AND STUDY DESIGN

Data from the Korea National Health and Nutrition Examination Survey were used; the sample analyzed in this study consisted a total of 15,013 respondents over 19 years old who had no missing values for the urinalysis or outcome variables. Urinary sodium was significantly lower in fem ales (p<0.05).

RESULTS

The rate of hypertension and diabetes was significantly lower in women (p<0.05). Adjusted odds ratios of urinary sodium and their 95% confidence intervals in relation to the frequency of tooth brushing (≤1, 2, and ≥3 times per day, respectively) were 1, 0.898 (0.704, 1.145), and 0.734 (0.573, 0.939) for women (p<0.05). This association between sodium uptake and oral health behavior was independent of various potential confounding factors such as age, body mass index, smoking, drinking, exercise, diabetes, and hypertension.

CONCLUSIONS

Poor oral health behavior was associated with higher sodium consumption in women. Oral health behavior may be considered an independent risk indicator for high urinary sodium in Korean women.

Incidence, prevalence, and mortality of Adamantiades-Behçet's disease in Korea: a nationwide, population-based study (2006-2015)

BACKGROUND

The epidemiology of Adamantiades-Behçet's disease varies among ethnic populations worldwide. Trends in the incidence of Adamantiades-Behçet's disease have not been investigated based on the Korean National Health Insurance database.

OBJECTIVES

This study investigated the incidence and mortality of Adamantiades-Behçet's disease by age using nationwide population data in Korea.

METHODS

A nationwide population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2006 to 2015. The incidence of Adamantiades-Behçet's disease was calculated by age, sex, calendar year and habitat. And comorbid metabolic diseases were also analysed in patients with Adamantiades-Behçet's disease.

RESULTS

The annual incidence of Adamantiades-Behçet's disease per 100 000 person-years was 3.976 (2.587 for males and 5.373 for females) from 2006 to 2015. The incidence of Adamantiades-Behçet's disease peaked among people in their 40s (6.561 per 100 000 person-years). Incidence was significantly higher in subjects with comorbid metabolic conditions, such as diabetes mellitus, hypertension and dyslipidemia. The mortality rate per 1000 person-years increased with age in patients with Adamantiades-Behçet's disease.

CONCLUSIONS

This study showed the incidence, prevalence and mortality of Adamantiades-Behçet's disease. Metabolic conditions increased the risk of Adamantiades-Behçet's disease among Koreans.

Gender differences in the relationship between socioeconomic status and height loss among the elderly in South Korea: Korean National Health and Nutrition Examination Survey 2008-2010

This study aimed to examine average height loss and the relationship between height loss and socioeconomic status (SES) among the elderly in South Korea.Data were obtained from the Korean National Health and Nutrition Examination Survey 2008-2010. A total of 5265 subjects (2818 men and 2447 women) were included. Height loss was calculated as the difference between the subject's self-reported maximum adult height and their measured current height. The height loss values were divided into quartiles (Q1-Q4) for men and women. SES was determined using a self-reported questionnaire for education level, family income, and occupation.Height loss was associated with SES in all age groups, and mean height loss increased with age. In the relationship between education level and maximum height loss (Q4), men with ≤6, 7-9, or 10-12 years of education had higher odds ratios for the prevalence of height loss (Q4) than men with the highest education level (≥13 years). With regard to the relationship between the income level and height loss (Q4), the subjects with the lowest income had an increased prevalence of maximum height loss (Q4) than the subjects with the highest income (odds ratios = 2.03 in men and 1.94 in women). Maximum height loss (Q4) was more prevalent in men and women with a low SES and less prevalent in men with a high SES than in men with a middle SES.Height loss (Q4) was associated with education level in men and with income level (especially low income) in men and women. Height loss was also associated with a low SES in men and women.

Atopic dermatitis is inversely associated with hepatitis B antigen positivity: a population-based cohort study

BACKGROUND

No clear association between hepatitis B virus (HBV) infection and atopic dermatitis (AD) has been established. Some studies have reported that subjects with HBV had an increased risk of atopy; other studies reported an inverse association between HBV seropositivity and allergic diseases.

OBJECTIVE

We evaluated the association between AD and hepatitis B antigen (HBsAg) positivity using Korean National Health and Nutrition Examination Survey data.

METHODS

In total, 14 776 participants aged >19 years were included in the analysis. Multiple logistic regression analyses were used to evaluate the odds ratio of HBsAg positivity in association with AD and asthma.

RESULTS

The prevalence of HBsAg positivity was lower in individuals with AD than in those without AD (mean [SE], 0.7% [0.4] vs. 3.7% [0.2]; P < 0.001). However, HBsAg positivity was not significantly associated with asthma (3.7% [0.2] vs. 2.8% [0.8]; P < 0.001). HBsAg positivity decreased the risk of AD significantly (OR = 0.223; 95% CI = 0.069-0.72).

CONCLUSIONS

This study demonstrates an inverse association between AD and HBsAg positivity using a nationwide, population-based, cross-sectional health examination and survey.

Associations between the number of natural teeth and the maternal age at childbirth or history of parity in postmenopausal women: The 2010-2012 Korea national health and nutrition examination survey

BACKGROUND

The relationship between reproductive factors, including pregnancy and delivery, and the number of teeth in postmenopausal women remains to be revealed.

OBJECTIVES

The aim of this study was to evaluate the relationship between age at first and last delivery, parity and the number of natural teeth in postmenopausal women, using nationally representative data.

MATERIAL AND METHODS

Data from the Korea National Health and Nutrition Examination Survey between 2010 and 2012 were used, and the analysis in this study was confined to a total of 4,060 respondents who had gone through menopause and had no missing values for the reproductive factors and outcome variables. The total number of natural teeth was then calculated after excluding third molars, and frequency of tooth brushing was recorded as oral health behavior. Univariate and multivariate logistic regression analyses were used to assess the associations between the number of natural teeth and reproductive factors.

RESULTS

Both a woman's age at her last childbirth and the number of pregnancies had statistically significant effects on the number of natural teeth remaining after menopause. With each one-year increase of age at a woman's last delivery, the number of natural teeth decreased by a value of 0.12 (p < 0.05). Similar trends were seen with increases in parity, which resulted in decreases in the number of natural teeth by 0.65 (p < 0.05). The odds ratios of the percentage of individuals with a 20 or fewer teeth tended to increase with increases in the woman's age at her last childbirth.

CONCLUSIONS

This study identified an association between the number of natural teeth and a woman's age at her last childbirth as well as between the number of natural teeth and parity. Higher ages at last childbirth and higher parity were found to be potential risk indicators for tooth loss in postmenopausal women.