Recently, medical research using big data has become very popular, and its value has become increasingly recognized. The Korean National Health Information Database (NHID) is representative of big ...data that combines information obtained from the National Health Insurance Service collected for claims and reimbursement of health care services and results obtained from general health examinations provided to all Korean adults. This database has several strengths and limitations. Given the large size, various laboratory data, and questionnaires obtained from medical check-ups, their longitudinal nature, and long-term accumulation of data since 2002, carefully designed studies may provide valuable information that is difficult to obtain from other forms of research. However, consideration of possible bias and careful interpretation when defining causal relationships is also important because the data were not collected for research purposes. After the NHID became publicly available, research and publications based on this database have increased explosively, especially in the field of diabetes and metabolism. This article reviews the history, structure, and characteristics of the Korean NHID. Recent trends in big data research using this database, commonly used operational diagnosis, and representative studies have been introduced. We expect further progress and expansion of big data research using the Korean NHID.
Abstract
To examine the effect of socioeconomic status (SES) as measured by three components of education level, income level, and occupation on prevalence and symptom severity of knee osteoarthritis ...(OA) and to determine which of these factors has the strongest association. We conducted a cross-sectional study using data from the Fifth Korean National Health and Nutrition Examination Survey that were collected between 2010 and 2012. Male and female participants 50 years or older were included. Analyses to examine the associations of the three SES components with prevalence and symptom severity of knee OA were performed. A total 9,071 participants was included in the study. As expected, lower education, lower income level, and non-managerial or no job were associated with higher prevalence of knee OA and knee symptoms. Among the three SES components, lower education was most strongly associated with knee pain and radiographic knee OA after adjusting for the other two. Lower education level is the component of SES that most strongly relates to higher prevalence of knee OA and knee symptoms. Improving societal education level might decrease the socioeconomic burden of knee OA.
There has been a need for research on the association between metabolic syndrome (MetS) and obstructive sleep apnea syndrome (OSAS) using large data such as nationwide population-based data that ...adjusts important confounding factors. Therefore, we investigated the relationship between MetS and OSAS. The data source we used was the National Health Insurance Service claims database managed by the Republic of Korea government, in which 10,113,560 individuals were enrolled in 2009 and followed up until 2018. The independent association of MetS with the risk of OSAS was determined using a Cox proportional hazards model with adjustment for age, sex, smoking status, alcohol consumption, regular physical exercise, and body mass index. Our results showed that MetS were strongly associated to OSAS which was adjusted for several confounding factors. Also, we found men, increased waist circumference and increased triglyceride are important risk factors for OSAS.
Abstract Background Menstrual cycle irregularity is common among adolescents and can induce mental health problems such as stress, depression, and suicidal ideation. We examined the association ...between mental health problems and menstrual cycle irregularity among adolescent Korean girls. Methods This population-based cross-sectional study was on 808 female adolescents (12–18 years of age) participating in the 2010–2012 Korean National Health and Nutrition Examination Survey. Psychological stress, depressive mood, suicidal ideations, suicide attempts, and psychological counseling were assessed through questionnaires and surveys, and hierarchical multivariable logistic regression analysis was performed. Results The risk of menstrual cycle irregularity tended to increase, as the number of mental health problems increased (P for trend = 0.016). High stress levels, depressive mood, and psychological counseling were associated with increased risks of menstrual cycle irregularity (odd ratio 95% confidence interval = 1.88 1.1–3.21, 2.01 1.01–4.03, and 2.92 1.16–7.34, respectively) even after adjusting for age, body mass index, alcohol consumption, smoking status, physical activity, hemoglobin level, monthly household income, weight loss attempts, age at menarche, and sleep duration. Suicidal ideation was not significantly associated with menstrual cycle irregularity. Limitations Menstrual irregularity was evaluated based solely on subjects’ self-reports, which are subject to their subjective perceptions and appraisal. Cross-sectional design and retrospective data could not draw causal relationship. Conclusions Positive associations were observed between mental health problems and menstrual cycle irregularity among adolescent Korean girls. More attention should be paid towards mental health, to improve menstrual cycle regularity and help prevent related chronic diseases later in life.
Periodontal disease is a risk factor for diabetes and metabolic syndrome, and non-surgical periodontal treatment has been shown to help maintain stable blood sugar in diabetic patients. Determining ...the level of preventive scaling in patients with metabolic syndrome will help manage the disease. The purpose of this study was to investigate the extent to which people with metabolic syndrome or bad lifestyle performed scaling and the association between preventive scaling and metabolic syndrome or lifestyle in a large population.
This study was conducted on adults aged 20 years or older from January 2014 to December 2017 in the National Health Insurance System (NHIS) database. Among 558,067 people who underwent health checkups, 555,929 people were included. A total of 543,791 people were investigated for preventive scaling. Metabolic syndrome components were abdominal obesity, lower high density lipoprotein cholesterol (HDL)-C, high triglycerides, high blood pressure and hyperglycemia. Unhealthy lifestyle score was calculated by assigning 1 point each for current smokers, drinkers, and no performing regular exercise.
When multiple logistic regression analysis was performed after adjusting for age, sex, income, body mass index (BMI), smoking, drinking and regular exercise, the Odds ratios (OR) and 95% confidence intervals (CI) of the group with 5 metabolic syndrome components were 0.741 (0.710, 0.773) (p<0.0001). After adjustment for age, sex, income, BMI, smoking, drinking, regular exercise, diabetes, hypertension and dyslipidemia, the OR (95% CI) of the group with unhealthy lifestyle score = 3 was 0.612 (0.586, 0.640) (p<0.0001).
The more metabolic syndrome components, and the higher unhealthy lifestyle score, the less scaling was performed.
A high visit-to-visit variability in cholesterol levels has been suggested to be an independent predictor of major adverse cardiovascular events in patients with coronary artery disease (CAD). ...Because whether this notion applies to general population is not known, we aimed to investigate the associations between total cholesterol (TC) variability and the risk of all-cause mortality, myocardial infarction (MI), and stroke.
We identified 3 656 648 subjects without a history of MI and stroke who underwent ≥3 health examinations from 2002 to 2007 in the Korean National Health Insurance System cohort. Total cholesterol variability was measured using the coefficient of variation (CV), standard deviation (SD), and variability independent of the mean (VIM). There were 84 625 deaths (2.3%), 40 991 cases of MI (1.1%), and 42 861 cases of stroke (1.2%) during the median follow-up of 8.3 years. There was a linear association between higher TC variability and outcome measures. In the multivariable adjusted model, the hazard ratios and 95% confidence intervals comparing the highest vs. lowest quartiles of CV of TC were 1.26 (1.24-1.28) for all-cause mortality, 1.08 (1.05-1.11) for MI, and 1.11 (1.08-1.14) for stroke, which was independent of mean TC levels and the use of lipid-lowering agents. The results were consistent when modelling variability of TC using SD and VIM, and in various sensitivity analyses.
High variability in lipid levels is associated with adverse health-related outcomes. These findings suggest that lipid variability is an important risk factor in the general population.
To examine the association between the presence and severity of migraine and development of primary open-angle glaucoma (POAG) using a nationwide population-based longitudinal cohort data.
Data were ...retrieved from the Korean National Health Insurance Service for 2,716,562 individuals aged ≥ 40 years and assessed for the development of POAG from 2009 through 2018. Subjects were classified into the following 3 groups: healthy control subjects, subjects with mild migraine, and those with severe migraine. Hazard ratios (HR) of glaucoma development were calculated for each group. Subgroup analyses of subjects stratified by age, sex, lifestyle factors (smoking, drinking, and body mass index (BMI)), and comorbidities (diabetes, hypertension, and dyslipidemia).
During the 9-year follow-up period, the incidence rate of POAG per 1000 person-years was 2.41 and 3.25 in subjects without and with migraine, respectively. Among the migraine group, the incidence rate was 3.14 and 3.89 in mild and severe subgroups, respectively. The HR was 1.355 (95% CI, 1.300-1.412) and 1.188 (95% CI, 1.140-1.239) before and after adjusting for potential confounding factors in the migraine group per se. Regarding the severity of migraine, the adjusted HRs were 1.169 (95% CI, 1.117-1.224) in the mild migraine group, and 1.285 (95% CI, 1.166-1.415) in the severe migraine group compared to the control group. The results were consistent in subgroup analyses after stratifying by age, sex, lifestyle factors, and comorbidities.
Migraine is associated with increased risk of POAG development. Furthermore, chronic and severe migraine is associated with greater risk of POAG development.
Regarding to known association between underweight and non-tuberculous mycobacterial pulmonary disease (NTM-PD), the underweight was simply categorized as body mass index (BMI) less than 18.5 kg/m
, ...mainly because of its low prevalence. We aimed to better define the impact of BMI severity on NTM-PD development. We analysed health data from 4,332,529 individuals examined in 2009 and followed up until December 2017 to determine the incidence of NTM-PD. Based on the BMI in kg/m
, the population was categorized into mild (17.00-18.49), moderate (16.00-16.99), and severe underweight (< 16.00) groups. Using Cox proportional-hazards analyses, hazard ratios for NTM-PD were calculated according to the severity of underweight in reference to normal BMI (18.50-22.99). Over a median follow-up of 5.6 ± 1.2 years, 6223 participants developed NTM-PD. Risk of NTM-PD increased significantly with the severity of underweight: multivariate adjusted hazard ratios (95% confidence intervals) for mild, moderate, and severe underweight were 2.34 (2.17-2.52), 3.50 (3.07-3.99), and 4.35 (3.63-5.21), respectively. In subgroup analysis, being younger (< 65 years old) or male exacerbated the effect of severe underweight on the risk of NTM-PD. This study proved that as underweight categories became more severe, the risk of NTM-PD increased proportionally.
We evaluate the risks of various urological disorders that require treatments according to obesity and metabolic health status using a nationwide dataset of the Korean population. 3,969,788 patients ...who had undergone health examinations were enrolled. Participants were classified as "obese" (O) or "non-obese" (NO) using a BMI cut-off of 25 kg/m2. People who developed ≥ 1 metabolic disease component in the index year were considered "metabolically unhealthy" (MU), while those with none were considered "metabolically healthy" (MH). There were classified into the MHNO, MUNO, MHO, and MUO group. In BPH, chronic renal disease, neurogenic bladder, any medication related to voiding dysfunction, alpha-blocker, and antidiuretics, age and gender-adjusted hazard ratio (HR) was highest in MUO, but higher in MUNO than in MHO. In stress incontinence, prostate surgery, and 5alpha-reductase, HR increased in the order of MUNO, MHO, and MUO. In prostatitis, anti-incontinence surgery, and cystocele repair, HR was higher in MHO than MUNO and MUO. In cystitis, cystostomy, and anticholinergics, HR was higher in MUNO and MUO than MHO. In conclusion, obesity and metabolic health were individually or collaboratively involved in urological disorders related to voiding dysfunction. Metabolic healthy obesity needs to be distinguished in the diagnosis and treatment of urological disorders.
PDF
