Kyungdo Han

• Doctor of Philosophy
• Soongsil University

Background/Objectives: Fecal calprotectin (FC) is a biomarker of intestinal inflammation widely used in the assessment of gastrointestinal disorders. However, its role in chronic kidney disease (CKD) remains unclear. Given the growing recognition of the gut–kidney axis in CKD pathophysiology, this study aimed to investigate the association between...

Purpose Protective lifestyle behaviors could potentially mitigate the risk of depression in breast cancer survivors. This study examined the association between changes in key health behaviors and depression risk after breast cancer diagnosis and treatment. Methods This nationwide cohort study assessed 30,523 breast cancer survivors without a prio...

Aims Proteinuria is a risk factor for end‐stage kidney disease (ESKD) and cardiovascular disease (CVD) in patients with diabetes. However, the clinical implications of fluctuating proteinuria are unclear. We investigated the proteinuria burden and the risks of clinical outcomes in patients with diabetes using the Korean National Health Insurance Se...

This study aims to investigate the incidence of new-onset atrial fibrillation (AF) in individuals with type 2 diabetes mellitus (T2DM) across different categories of steatotic liver disease (SLD). Using a health examination database between 2009 and 2012, this study included 2,480,880 patients. Participants were categorized into five groups based o...

Background/Objectives: Cardiovascular disease (CVD) risk may be based on the sequence of hypertension (HTN) and diabetes mellitus (DM) occurrence since the pathophysiological mechanisms might not be the same. The present study examined the risk of CVD according to the precedent relationship between HTN and DM. Methods: Participants with both HTN an...

The number of large-scale epidemiological studies using administrative databases has rapidly increased in recent years. However, in observational studies, the outcomes of interest are heavily influenced by concurrent or pre-existing comorbidities, which act as confounders, and appropriate adjustment of comorbidities is essential to minimize bias. A...

This study aimed to evaluate the prevalence and risk factors for undiagnosed age-related macular degeneration (AMD) in the Korean population. This cross-sectional study utilized data from the Korea National Health and Nutrition Examination Survey (KNHANES 2017–2020), which included a total of 13,737 subjects of 40 years or older. Cases in which AMD...

Importance Living alone and mental health disorders, including depression and anxiety, are associated with high suicide risk, but their combined impact remains underexplored. Objective To examine the association of living arrangements and depression or anxiety with suicide risk. Design, Setting, and Participants This population-based cohort study...

Aims: We investigated the impact of aerobic exercise on clinical outcomes in patients with diabetes undergoing percutaneous coronary intervention (PCI). Methods: We analyzed a nationwide prospective population database from the Korean National Health Insurance System. We included 8,225 patients with diabetes who had undergone PCI and documented...

Purpose Triglyceride-glucose (TyG) index is a reliable marker of insulin resistance. Although the TyG index is useful for identifying individuals at a high risk of future cardiovascular events and mortality in the general population, its clinical impact on young adults remains unclear. This study aimed to investigate the association between the TyG...

Background Although increased mortality in patients with Parkinson disease (PD) is well documented, studies on suicide‐related mortality have yielded conflicting results. Moreover, the impact of comorbidities, socioeconomic factors and health behaviours as potential risk factors for suicide remains underinvestigated. This study aimed to investigate...

Aims A minority of patients with heart failure (HF) are prescribed the maximal dose of the angiotensin receptor–neprilysin inhibitor sacubitril/valsartan. We investigated the effectiveness of submaximal doses of sacubitril/valsartan in a real-world cohort. Methods and results Patients with HF with reduced ejection fraction prescribed sacubitril/va...

Objectives Although evidence suggests that the overall prevalence of type 2 diabetes mellitus (T2DM) was already higher in the acromegaly group than in the general population several years before diagnosis, the effect of glycaemic status on the risk of developing acromegaly remains unclear. Design Retrospective cohort study. Setting Data were obt...

BACKGROUND Although the link between cardiovascular disease (CVD) and various cancers is well-established, the relationship between CVD risk and colorectal cancer (CRC) remains underexplored. AIM To elucidate the relationship between CVD risk scores and CRC incidence. METHODS In this population-based cohort study, participants from the 2009 Nationa...

Background Migraine is linked to increased suicidal behaviour, but its relationship with suicide mortality remains underexplored. In South Korea, suicide rates are among the highest in Organisation for Economic Co-operation and Development nations, particularly in young adults. Objective To investigate the effect of migraine on suicide mortality i...

Although higher prevalence of systemic sclerosis (SSc) in women than in men is well-known, it is unclear to what degree women are at higher risk of developing incident SSc. This study aims to assess the risk of incident SSc comparing women vs. men, and to identify subsets of individuals in whom the risk difference according to sex is more prominent...

Background Proteinuria is a risk factor for cardiovascular events, but its prognostic value for sudden cardiac arrest (SCA) in young individuals remains unproven. We aimed to evaluate whether proteinuria in young people is associated with an increased risk of SCA. Methods and Results Individuals aged between 20 and 39 years who underwent health sc...

This study investigates whether ocular motor cranial neuropathy (OMCN) can predict the onset of thyroid cancer given its association with common cardiovascular risk factors including obesity, diabetes mellitus (DM), hypertension, and dyslipidemia. We conducted a retrospective, nationwide, population-based cohort study utilizing data from the Korean...

Background/Aims Gamma-glutamyl transferase (GGT) is a known surrogate marker of hepatic dysfunction and oxidative stress. However, data on its association with pancreatic disease, especially pancreatic cystic neoplasm, is unknown. This study aimed to investigate the association of GGT with the incidence of pancreatic cystic neoplasm. Methods Partic...

Background The influence of duration of type 2 diabetes mellitus (T2DM) on the likelihood of developing new-onset dementia in post-stroke population is not well understood. Therefore, we aimed to clarify the relationship between the duration of T2DM and the risk of developing dementia in the post-stroke population. Methods Leveraging the Korean Na...

Background Limited evidence exists regarding the consistent and synergistic benefits of early rhythm control (ERC) and healthy lifestyle (HLS) on major adverse cardiovascular events (MACEs) in young patients with atrial fibrillation (AF). Aims To evaluate the individual and synergistic benefits of ERC and HLS on MACEs in young AF patients. Method...

We investigated the risk of ischemic stroke in ALS and analyzed the effect of ALS-related physical disability using the Korean National Health Insurance Service database. A total of 2,251 ALS patients diagnosed between January 1, 2012, and December 31, 2015, and 1:10 age- and sex-matched control populations were included. Cases that participated in...

We investigated the effect of differential blood pressure (BP) levels on future end-stage renal disease (ESRD) in patients with type 2 diabetes mellitus (T2DM) and established coronary artery disease with a previous record of percutaneous coronary intervention (PCI). Using health check-up data from the Korean National Health Insurance Service (2015...

Background: Patients with diabetes are known to be at high risk for end-stage kidney disease (ESKD), but the accurate annual risk data for new-onset ESKD is still limited. In South Korea, the prevalence and incidence of ESKD are increasing more rapidly compared to the global average. This study aimed to determine the incidence rate (IR) of ESKD by...

Introduction Using a nationwide population-based cohort, we primarily investigated whether overall and site-specific cancer risk are increased in patients with acromegaly. Materials and methods The study included 2,382 patients with acromegaly and 11,910 controls aged above 20, from 2006 to 2016. Cox hazards regression analysis was used, adjusting...

Studies have highlighted complex bidirectional relationships between autoimmune diseases and depressive disorders. Given that early mental health interventions have substantial public health implications, this study investigated association between optic neuritis, an autoimmune inflammatory disorder of the optic nerve, and risk of developing depres...

We aimed to assess whether patients with rheumatoid arthritis (RA) have a higher risk of developing acute and chronic pancreatitis compared to individuals without RA. We identified 54,910 individuals with RA between 2010 and 2017. After exclusion, they were matched in a 1:3 ratio based on age and gender to control population without RA. Cox regress...

Background The long‐term effects of cholecystectomy on mortality and cardiovascular disease (CVD) in patients with diabetes have not been evaluated. In the present study, we investigated the longitudinal effects of cholecystectomy on mortality and CVD in a population‐based cohort with type 2 diabetes (T2D). Methods In total, 2 216 930 national hea...

Background Diabetes in older adults is becoming a significant public burden to South Korea. However, a comprehensive understanding of epidemiologic trends and the detailed clinical characteristics of older adults with diabetes is lacking. Therefore, we evaluated epidemiologic trends and the metabolic and lifestyle characteristics of diabetes in Kor...

Purpose Evidence on the associations between categorical mammographic density and breast cancer risk by tumor invasiveness remains limited in Asian women. This large, population-based cohort study investigated the distribution of mammographic density by age and menopausal status, as well as its association with the risks of invasive breast cancer a...

Background Little information is available regarding whether active physical activity lowers mortality risk in individuals with bronchiectasis. Methods We used the Korean National Health Insurance Service database from 2010 to 2016 to evaluate the association between changes in physical activity and mortality risk in individuals with bronchiectasi...

Background Lifestyle-related factors have been studied as a fundamental aspect in the onset and progression of type 2 diabetes mellitus. However, behavioral factors are easily overlooked in clinical practice. This study investigated whether lifestyle changes were associated with diabetes remission in newly diagnosed type 2 diabetes patients. Metho...

Background Despite a high tuberculosis incidence in Korea, the association between tuberculosis and depression remains underexplored. This study aims to assess depression risk in tuberculosis survivors. Methods Utilizing South Korea’s National Health Insurance Sharing Service (NHISS) database, we conducted a gender-age-matched analysis comparing d...

Background: The mortality of sepsis without direct drugs is high. The association between prediabetes, based on a single fasting glucose (FG), or long-term type 2 diabetes mellitus (T2DM) and sepsis remains unclear. Methods: Of the adults aged ≥20 years who were included in the National Health Screening Program (NHSP) in 2009, 40% were randomly...

Although a robust association between metabolic dysfunction-associated fatty liver disease (MASLD) and cardiovascular disease (CVD) has been established, the impact of MASLD on CVD risk in young adults has not been fully evaluated. This population-based study included adults aged 20–39 years who underwent health screening examinations from 2009 to...

Background: Premorbid allergic diseases are linked with the development of age-related macular degeneration (AMD), however, the risk of allergic diseases among patients with AMD is largely unknown. Objective: To evaluate the association between AMD with or without visual disability (VD) and the risk of allergic diseases. Methods: A total of 2,...

Objective Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with several comorbidities, including an increased risk of certain cancers. This study aimed to investigate the potential associations between RA and increased risk of urological cancers—specifically kidney, bladder, prostate and testicular cancers—and the influence of...

Background While breast cancer increases the risk of diabetes mellitus (DM), its temporal relationships according to age group and treatment risk factors for DM have not been comprehensively investigated. In this study we explore temporal patterns of DM risk in breast cancer survivors, stratified by age and risk factors. Methods Using the National...

Interstitial lung disease (ILD) leads to worse outcomes in subjects with rheumatoid arthritis (RA). Few large-scale longitudinal studies have provided comprehensive data on the incidence and risk of ILD in RA compared with non-RA populations. We compare the risk of incident ILD in subjects with RA and matched controls, while also evaluating the imp...

Background Uterine leiomyomatosis and psoriasis are prevalent conditions and shared pathophysiological factors indicate a potential association. However, a direct correlation has not been established. We investigated the relationship between uterine leiomyomatosis and the risk of new-onset psoriasis in Korean females of reproductive age. Methods T...

Acromegaly is a rare endocrine disorder caused by excessive growth hormone secretion. Its low prevalence poses challenges in studying its long-term prognosis and systemic effects. To address this research gap, we conducted five studies using nationwide cohort data from the Korean National Health Insurance Database (NHID). This review consolidates t...

Background: We examined the distribution of time to insulin therapy (TIT) post-diabetes diagnosis and the hazard of severe hypoglycemia (SH) according to TIT in Korean adults initially diagnosed with type 2 diabetes (T2D) and who progressed to insulin therapy. Methods: Using data from the Korean National Health Insurance Service (2002 to 2018),...

Introduction: Several previous studies showed increased risk in stroke in Rheumatoid Arthritis (RA) patients. However, no study has shown how risk differ among different serostatus of RA—seropositive RA (SPRA) and seronegative RA (SNRA) —and types of strokes —ischemic stroke (IS) and hemorrhagic stroke (HS). Hypothesis: We hypothesize that the inci...

Purpose Widely used breast cancer risk-prediction tools are based on data from Western countries, but risk factors may differ for Asian women. Hence, we aimed to develop a risk assessment tool for breast cancer in Asian women using a nationwide, population-based mammographic screening cohort. Materials and Methods Women aged ≥40 years who underwent...

Background: Immune-mediated inflammatory diseases (IMIDs) are associated with chronic inflammation that may increase fracture risk; however, their impact within specific populations, such as those with type 2 diabetes mellitus (T2DM), remains unclear. This study aimed to evaluate the association between IMIDs and fracture risk, leveraging a large,...

Background Diabetes mellitus (DM) and proteinuria each independently raise the risk of atrial fibrillation (AF). We aimed to investigate the relationship between proteinuria and the risk of incident AF across glycemic stages. Methods A cohort of 4,044,524 individuals without prior AF and type 1 DM was selected from the 2009 Korean National Health...

Background Vertebral fractures are a common medical issue. Physical activity helps improve bone health and manage the risk of fractures. However, much controversy exists about the association between physical activity and vertebral fractures. Therefore, we aimed to investigate the association between changes in regular physical activity (RPA) and v...

Abstracts Mental disorders are associated with an increased risk of premature death, including suicide. This study aimed to examine the risk of suicide and all-cause death in patients with mental disorders after considering demographic, clinical, and lifestyle factors. Data from the National Health Insurance Sharing Service database and linked data...

Background Previous studies have shown that weight change has a reverse J-shape association with all-cause mortality. However, its association with suicide mortality remains undetermined. In this study, we investigated the association between weight change and suicide mortality using a large-scale, population-based cohort from the Korean National H...

Background This study investigates the effect of botulinum toxin A on lipid layer thickness (LLT) and blink dynamics in patients with benign essential blepharospasm (BEB) compared to dry eye disease (DED) patients. Methods We reviewed the medical records of patients with dry eye disease (DED) and BEB treated with botulinum toxin A (BoT A) injectio...

Background/Objectives: Uterine leiomyomas are the most common benign gynecological tumors in women of reproductive age and are often associated with localized symptoms. However, emerging evidence suggests a link between uterine leiomyomas and systemic conditions such as cardiovascular disease (CVD), particularly myocardial infarction (MI) and ische...

Objective: To compare minimally invasive surgery with traditional open surgery, analyze the current application status of health economic evaluations in the treatment of digestive tract cancers, such as esophageal cancer, gastric cancer, and colorectal cancer by minimally invasive surgery and provide evidence for the rational selection of clinical...

Background The effects of glomerular hyperfiltration (GHF) on cardiovascular disease (CVD) risk in patients with type 2 diabetes mellitus (T2DM) were explored. Methods This retrospective cohort study enrolled 1,952,053 patients with type 2 diabetes mellitus from the Korean National Health Insurance Service database between 2015 and 2016. Based on...

This cohort study assesses the role of postdiagnosis and prediagnosis in weight gain in individuals with higher risk for cardiac dysfunction.

Background Suicide is a significant yet preventable public health issue. Body mass index (BMI) is a readily measurable indicator associated with various health outcomes. However, the relationship between BMI and suicidal death risk is complex and warrants further investigation, particularly within contemporary, non-Western contexts with considerati...

Background Amputation confers disabilities upon patients and is linked to cardiometabolic morbidity and mortality. We aimed to compare the incidence of type 2 diabetes (T2DM) between individuals following amputation with those of the general population. Methods We performed a population-based retrospective cohort study using the Nationwide Health...

Although alcohol consumption and depression are well-known risk factors for dementia, the effect of alcohol consumption in subjects with depression on the risk of dementia remains unclear. National claim data of South Korea were used in this study. A total of 1,856,078 patients diagnosed with depression who had received health examination within 2...

Background Breast cancer survivors (BCS) face a higher risk of cardiovascular disease (CVD) due to treatment-related cardiotoxicity and pre-existing conditions. We investigated how post-diagnosis weight changes and obesity impact CVD risk in this population. Method Using the Korean National Health Insurance Service database (2010–2019), BCS withou...

Background: Amputation confers disabilities upon patients and is associated with substantial cardiovascular and metabolic morbidity and mortality. We aimed to compare the incidence of end-stage kidney disease (ESKD) between individuals with amputation and the general population. Methods: A population-based retrospective cohort study was performe...

Aims We aimed to examine the impact of gout on cardiovascular disease (CVD) and mortality risk in patients with type 2 diabetes and explore whether chronic kidney disease (CKD) modifies this association. Materials and Methods Using the Korean National Health Insurance Service database, 757 378 individuals with type 2 diabetes were classified into...

Importance There is limited evidence regarding the association between age at menopause and incident type 2 diabetes (T2D). Objective To investigate whether age at menopause and premature menopause are associated with T2D incidence in postmenopausal Korean women. Design, Setting, and Participants This population-based cohort study was conducted a...

Purpose Smoking may have a protective role in developing ulcerative colitis (UC) but have the opposite effect on Crohn’s disease (CD). This study aimed to determine the risk of developing inflammatory bowel disease (IBD) according to smoking status and onset age of smoking. Materials and Methods We collected data on the smoking experiences of part...

The Korean National Health Information Database (NHID), which contains nationwide real-world claims data including sociodemographic data, health care utilization data, health screening data, and healthcare provider information, is a powerful resource to test various hypotheses. It is also longitudinal in nature due to the recommended health checkup...

Background This study aimed to investigate the prevalence, management, and comorbidities of diabetes mellitus among Korean adults. Methods Data from the Korea National Health and Nutrition Examination Survey (2019–2022) were analyzed to assess the prevalence, treatment, risk factors, and comorbidities of diabetes. Comparisons between young and old...

Because effective reinforcement materials must have both high capacity for load bearing and high resistance to deformation under external force, they require both high mechanical tensile strength and a high elasticity modulus. Both strength and modulus are usually amplified at cryogenic temperatures, so properties at both cryogenic and room tempera...

Body mass index (BMI) is associated with chronic obstructive pulmonary disease (COPD) risk. We investigated the association between BMI and the risk of COPD among young individuals. Using the Korean National Health Information Database, we screened individuals aged 20–39 years who participated in the national health examination between 2009 and 201...

Background: This national population-based study aimed to assess the cumulative burden of non-alcoholic fatty liver disease (NAFLD) measured via the fatty liver index (FLI) and its association with kidney cancer risk in young men aged 20–39. Methods: Using the Korean National Health Insurance Service database, we examined a cohort of 1,007,906 men...

Background Depression among breast cancer survivors is a significant concern affecting their long-term survivorship and quality of life. This study investigates the incidence of depression among breast cancer survivors and identifies associated risk factors. Methods This retrospective cohort study used data from the Korean National Health Insuranc...

Objective Previous studies have investigated obesity and appetite changes in patients with depression, which consisted of a small age range of adults and used body mass index rather than abdominal obesity. The objective of this study is to examine the relationship between abdominal obesity and the risk of depression by sex and age groups. Methods...

OBJECTIVE To explore all-cause mortality and the incidence of cardiovascular and renal complications among patients with young-onset diabetes in South Korea using a nationwide registry database. RESEARCH DESIGN AND METHODS Data were collected from the Korean National Health Insurance Service–National Sample Cohort database from 2006 to 2019 for pa...

Background: Several meta-analyses have found no association between Graves' disease (GD) and an increased risk of incident diabetes; however, the intricate relationship between thyroid dysfunction and diabetes remains underexplored. In this study, we aimed to evaluate the risk of incident type 2 diabetes (T2DM) in a population newly diagnosed with...

Background: Obstructive sleep apnea (OSA) is a sleep disorder associated with an increased risk of cardiovascular and metabolic complications. Albuminuria, an early marker of kidney damage, is a proposed risk factor for OSA and its adverse outcomes. The study explored the association between OSA and albuminuria in Korean adults. Methods: We scre...

Introduction Early age at menopause has been linked to various adverse health outcomes, but its association with suicide risk remains underexplored. This study aims to assess the relationship between age at menopause and suicide risk among postmenopausal women. Methods This retrospective cohort study analyzed data from the Korean National Health I...

Background Atrial fibrillation (AF) is associated with increased risks of adverse events including stroke and all-cause death. Understanding the pattern of causes of death (COD) with the relative risks in patients with AF compared to the non-AF population is essential in planning optimal care for patients with AF. We aimed to analyze the COD and it...

Background The Republic of Korea has reported the highest suicide rate globally since 2018. Previous studies have highlighted disability as a significant risk factor for suicide. However, comprehensive examination on the association between suicide mortality and severities and types of disabilities, and on how these associations vary according to s...

Objectives Patients with advanced chronic kidney disease suffer from hypertension, and kidney transplantation (KT) has potential to induce hypertension resolution. We hypothesized that hypertension resolution after KT is associated with better KT outcomes. Methods We identified KT recipients (2006–2015) who had pretransplant hypertension. They wer...

Background: Stroke survivors usually have many vascular risk factors (VRFs), and recent studies have reported the association of VRFs with cognitive decline among stroke survivors, which are also associated with PD risk. Therefore, we aimed to investigate how VRFs influenced the risk of PD occurrence in individuals with stroke. Methods: The Korean...

Background/aims: Elevated gamma-glutamyl transferase (GGT) levels indicate hepatic dysfunction and have been linked to an increased risk of pancreatobiliary cancers. However, this association, particularly in individuals with diabetes mellitus (DM), requires elucidation. We aimed to examine the association between elevated serum GGT levels and pan...

Background/Objectives: Despite the increasing prevalence of both spinal stenosis and obesity, their association remains controversial. This study aimed to investigate the relationship between body mass index (BMI) and the risk of lumbar spinal stenosis in the Korean population using nationwide data. Methods: We analyzed data from 2,161,684 adults a...

Background We aimed to assess the incidence of infective endocarditis (IE) and evaluate the impact of hypertension (HTN) with underweight on the risk of IE among patients with diabetic mellitus (DM) using a nationwide population-based cohort in Korea. Methods We identified 2,603,012 participants (57.4 ± 12.3 years) in the national health insurance...

Background Cancer survivors face an elevated risk of cardiovascular disease, with physical inactivity after cancer treatment potentially worsening this risk. Objectives The aim of this study was to investigate the association between physical activity before and after a cancer diagnosis and the risk for heart disease. Methods A nationwide cohort...