Myxoma of Nasal Ala in an Adult Patient / 대한이비인후과학회지

Myxoma most commonly occurs in the atria, but is rare in the nasal cavity. A 58-year-old male patient presented with a nasal mass. We used endoscopic endonasal approach for treatment, and the patient was finally diagnosed with nasal ala myxoma. We report here a rare case of a patient with nasal ala myxoma along with a literature review.

A Study on the Effects of Mucous Membrane of the Sinus by Severity of Sleep Breathing Disorder / 대한이비인후과학회지

Background and Objectives@#Obstructive sleep apnea (OSA) is an obstructive airflow disorder that occurs in the upper respiratory tract during sleep and is therefore associated with the occurrence of cardiovascular diseases. By examining the Lund-Mackay (L-M) scores and maxillary sinus mucosal conditions according to the severity of sleep breathing disorder (SBD), we tried to find out the association between SBD and sinus mucosal change.Subjects and Method Of the 189 patients who underwent sinus CT with a polysomnography test, 175 patients were enrolled in our study. We investigated the average L-M score and L-M score of five or higher, and the ratio of maxillary sinus mucosal thickness (MSMT) of 2 mm or higher. @*Results@#The average L-M score of study population was 0.98 points and the L-M score of five or more was found in 14 patients (8%). The MSMT of 2 mm or more was found in 25.5% of the study group. The average L-M scores for the different groups, namely, the simple snoring group, the mild OSA, the moderate OSA, and the severe OSA were 1.31 points, 0.77 points, 0.91 points, and 1.08 points, respectively. There was no significant difference (p=0.736) among them, and there was no correlation between the apnea-hypopnea index score and the L-M score (r=-0.052, p=0.499). There was no significant difference between OSA severity and MSMT (p=0.490). @*Conclusion@#There was no significant difference between the L-M score and MSMT depending on the severity of SBD. Therefore, it is believed that SBD will have little effect on the sinus mucosa.

Changes in Patients Who Receive Coverage for Positive Airway Pressure Therapy According to Alterations in National Health Insurance Benefit Standards for Mild Obstructive Sleep Apnea / 대한이비인후과학회지

Background and Objectives@#The aim of this study was to identify the frequency of indicators of National Health Insurance (NHI) coverage for positive airway pressure (PAP) therapy and to investigate the changes in patients receiving coverage for PAP therapy after the alterations were made in the insurance benefit standards for mild obstructive sleep apnea (OSA).Subjects and Method We divided the mild OSA patients into two groups according to altered categorization in insurance benefit standards (Mild1: 5≤AHI<10; Mild2: 10≤AHI<15). Eight indicators related to the NHI coverage were identified: four symptoms, three complications, and the minimal blood oxygen saturation during polysomnography (min SpO2) of ≤85% during polysomnography. We also investigated the change in the number of patients receiving insurance benefits under the altered insurance benefit standards. @*Results@#Of the 233 OSA patients, 66, 57, and 110 patients were diagnosed as mild, moderate and severe OSA, respectively. For all of them, the most common indicator related to NHI coverage for PAP therapy was the minimum SpO2 of less than 85% during polysomnography, and the second most common indicator was daytime sleepiness. In the mild OSA group, however, daytime sleepiness was found to be the most common indicator, found in 46 (70%) patients, followed by 38 (58%) patients with min SpO2 of less than 85%. In this group, 59 (89.4%) would have been benefited before the change in the insurance benefit standards whereas 51 patients (77.3%) would now be benefited under the changed insurance benefit standards. @*Conclusion@#Daytime sleepiness was the most commonly observed indicator in the mild OSA patients. The number of patients receiving insurance benefits for PAP therapy significantly decreased after the change was made in the NHI benefit standards for mild OSA

New Targeted Therapy for Non-Small Cell Lung Cancer / 결핵및호흡기질환

Lung cancer ranks first in cancer mortality in Korea and cancer incidence in Korean men. More than half of Korean lung cancer patients undergo chemotherapy, including adjuvant therapy. Cytotoxic agents, targeted therapy, and immune checkpoint inhibitors are used in chemotherapy according to the biopsy and genetic test results. Among chemotherapy, the one that has developed rapidly is targeted therapy. The National Comprehensive Cancer Network (NCCN) guidelines have been updated recently for targeted therapy of multiple gene mutations, and targeted therapy is used not only for chemotherapy but also for adjuvant therapy. While previously targeted therapies have been developed for common genetic mutations, recently targeted therapies have been developed to overcome uncommon mutations or drug resistance that have occurred since previous targeted therapy. Therefore, this study describes recent, rapidly developing targeted therapies.

Outcomes according to treatment modalities as a bridge to curative surgery for malignant obstruction of the proximal colon: stent versus stoma

Background/Aims@#The optimal treatment for acute malignant obstruction of the proximal colon (MOPC, proximal to the splenic flexure) remains challenging. Emergency resection, the traditional modality for MOPC, has shown significantly high mortality and morbidity rates, according to recent studies. This study aimed to investigate the clinical outcomes of stent vs stoma as a bridge to curative surgery for MOPC. @*Methods@#This retrospective cohort study included 72 patients who underwent endoscopic placement of a self-expanding metallic stent (SEMS) or loop ileostomy for MOPC at six referral centers between January 2011 and July 2021. Clinical and pathological characteristics, procedure-related complications, and long-term mortality rates after curative surgery were analyzed. @*Results@#During a mean follow-up period of 32 months, 30 patients (41.7%) underwent ileostomy preferentially for more proximal cancer, complete obstruction, and advanced tumor stage compared to the SEMS group. No difference was found in procedure-related complications, but five deaths were observed after ileostomy. Survival analysis for 5-year mortality after curative surgery showed no significant difference between the bridge modalities (log-rank p = 0.253). @*Conclusions@#In this study, SEMS as a bridge to surgery showed relatively safe results in terms of post-procedural mortality. However, these results should be considered when performing ileostomy in patients with more advanced malignant obstruction.

Long-term cardiovascular events in hypertensive patients: full report of the Korean Hypertension Cohort

Background/Aims@#This study evaluated the long-term cardiovascular complications among Korean patients with hypertension and compared them with that of controls without hypertension. @*Methods@#The Korean Hypertension Cohort (KHC) enrolled 11,043 patients with hypertension and followed them for more than 10 years. Age- and sex-matched controls without hypertension were enrolled at a 1:10 ratio. We compared the incidence of cardiovascular events and death among patients and controls without hypertension. @*Results@#The mean age was 59 years, and 34.8% and 16.5% of the patients belonged to the high and moderate cardiovascular risk groups, respectively. During the 10-year follow-up, 1,591 cardiovascular events (14.4%) with 588 deaths (5.3%) occurred among patients with hypertension and 7,635 cardiovascular events (6.9%) with 4,826 deaths (4.4%) occurred among controls. Even the low-risk population with hypertension showed a higher cardiovascular event rate than the population without hypertension. Although blood pressure measurements in the clinic showed remarkable inaccuracy compared with those measured in the national health examinations, systolic blood pressure (SBP) ≥ 150 mmHg was significantly associated with a higher risk of cardiovascular events. @*Conclusions@#This long-term follow-up study confirmed the cardiovascular event rates among Korean hypertensive patients were substantial, reaching 15% in 10 years. SBP levels ≥ 150 mmHg were highly associated with occurrence of cardiovascular event rates.

Effect of age on the prognosis of intrahepatic cholangiocarcinoma

Background/Aims@#Intrahepatic cholangiocarcinoma (iCCA) is a subgroup of cholangiocarcinoma and is the second- most-common primary hepatic tumor. Several predictive and prognostic factors have been analyzed; however, in this study we focused on the influence of age. Our aim was to use real-world results to determine the influence of age in iCCA patients. @*Methods@#A retrospective analysis of patients treated between 2005 and 2016 at Konkuk University Medical Center. In total, 133 patients with iCCA were identified. The mass-forming, periductal-infiltrating, and intraductal-growth types were included; patients with extrahepatic or hilar-type cholangiocarcinoma were excluded. We defined two groups: a younger group, age < 65 years, and an older group, age ≥ 65 years. Statistical analyses using univariate and multivariate Cox regression analyses, including the Kaplan-Meier method, were conducted. @*Results@#In total, 114 patients were enrolled. The two groups differed with regard to treatment options such as surgery with adjuvant chemotherapy or palliative chemotherapy (p = 0.012, p < 0.001). The younger group had significantly longer survival than the older group (p = 0.017). In the younger group, patients who received therapy had longer survival than those who did not (hazard ratio, 3.942; 95% confidence interval, 2.053 to 7.569; p < 0.001). Multivariate analysis indicated that younger age, lower bilirubin, low CA 19-9, and no lymph-node involvement were independent factors for improved survival. @*Conclusions@#Younger patients and those who underwent surgery with adjuvant chemotherapy had longer survival. The younger the patient, the more treatments received, including palliative chemotherapy.

Subtype-Based Microbial Analysis in Non-small Cell Lung Cancer / 결핵및호흡기질환

Background@#The human lung serves as a niche for a unique and dynamic bacterial community related to the development and aggravation of multiple respiratory diseases. Therefore, identifying the microbiome status is crucial to maintaining the microecological balance and maximizing the therapeutic effect on lung diseases. Therefore, we investigated the histological type-based differences in the lung microbiomes of patients with lung cancer. @*Methods@#We performed 16S rRNA sequencing to evaluate the respiratory tract microbiome present in bronchoalveolar lavage fluid. Patients with non-small cell lung cancer were stratified based on two main subtypes of lung cancer: adenocarcinoma and squamous cell carcinoma (SqCC). @*Results@#Among the 84 patients analyzed, 64 (76.2%) had adenocarcinoma, and 20 (23.8%) had SqCC. The α- and β-diversities showed significant differences between the two groups (p=0.004 for Chao1, p=0.001 for Simpson index, and p=0.011 for PERMANOVA). Actinomyces graevenitzii was dominant in the SqCC group (linear discriminant analysis [LDA] score, 2.46); the populations of Haemophilus parainfluenza (LDA score, 4.08), Neisseria subflava (LDA score, 4.07), Porphyromonas endodontalis (LDA score, 3.88), and Fusobacterium nucleatum (LDA score, 3.72) were significantly higher in the adenocarcinoma group. @*Conclusion@#Microbiome diversity is crucial for maintaining homeostasis in the lung environment, and dysbiosis may be related to the development and prognosis of lung cancer. The mortality rate was high, and the microbiome was not diverse in SqCC. Further large-scale studies are required to investigate the role of the microbiome in the development of different lung cancer types.

Korean treatment recommendations for patients with axial spondyloarthritis

We aimed to develop evidence-based recommendations for treating axial spondylarthritis (axSpA) in Korea. The development committee was constructed, key clinical questions were determined, and the evidence was searched through online databases including MEDLINE, Embase, Cochrane, KoreaMed, and Kmbase. Systematic literature reviews were conducted, quality of evidence was determined, and draft recommendations were formulated according to the Grading of Recommendations Assessment, Development, and Evaluations methodology. Recommendations that reached 80% consensus among a voting panel were finalized. Three principles and 21 recommendations were determined. Recommendations 1 and 2 pertain to treatment strategies, regular disease status assessment, and rheumatologist-steered multidisciplinary management. Recommendations 3 and 4 strongly recommend patient education, exercise, and smoking cessation. Recommendations 5–12 address pharmacological treatment of active disease using nonsteroidal anti-inflammatory drugs, glucocorticoids, sulfasalazine, biologics, and Janus kinase inhibitors. Recommendations 13–16 address treatment in stable disease. We suggest against spa and acupuncture as therapies (Recommendation 17). Recommendations 18 and 19 pertain to total hip arthroplasty and spinal surgery. Monitoring of comorbidities and drug toxicities are recommended (Recommendations 20 and 21). Recommendations for axSpA treatment in a Korean context were developed based on comprehensive clinical questions and evidence. These are intended to guide best practice in the treatment of axSpA.

The serotype-specific prevalence of pneumococci in hospitalized pneumonia patients with COPD: a prospective, multi-center, cohort study

Background/Aims@#The overall incidence of pneumococcal pneumonia is declining. However, the change in the pathogenic distribution of community-acquired pneumonia (CAP) in chronic obstructive pulmonary disease (COPD) patients and the serotype specificity of Streptococcus pneumoniae have not been evaluated in the post-era of pneumococcal vaccination in Korea. @*Methods@#We conducted a prospective, multi-center, cohort study from seven University-affiliated hospitals. The primary objective was the identification of serotype-specific prevalence of pneumococcal pneumonia in COPD patients hospitalized for CAP. For the purpose, we conducted serotype-specific urine antigen detection (SS-UAD) assays for S. pneumoniae. The secondary objectives were other clinical characteristics of pneumonia including vaccination status. @*Results@#The total number of participants was 349. Most of them were male (95.1%) with old ages (75.55 ± 8.59 y). The positive rate for S. pneumoniae was 9.2% with SS-UAD assay and the common serotypes were 22F, 6A, and 6B. In the sputum, Pseudomonas aeruginosa (5.0%) and Haemophilus influenzae (4.0%) were common pathogens. The vaccination rate was 78.8%, 53.0%, and 25.8% for influenza, pneumococcal polysaccharide vaccine 23 (PPV 23), and pneumococcal protein- conjugated vaccine 13 (PCV 13), respectively. Thirteen patients died during hospitalization (mortality rate; 3.7%). There was no difference in the respective rate of influenza vaccination (79.2% vs. 69.2%, p = 0.288) and PCV 13 vaccination (25.6% vs. 30.8%, p = 0.443) between survivors and the deceased. @*Conclusions@#Serotypes 22F, 6A, and 6B, which are covered either by PPV 23 or by PCV 13, are still common pneumococcal serotypes in COPD pneumonia in the post-vaccination era in Korea.

Endoscopic Submucosal Dissection for Treatment of Localized Gastric Mucosa-Associated Lymphoid Tissue Lymphoma: A Case Series

Background/Aims@#The treatment for gastric mucosa-associated lymphoid tissue lymphoma (MALToma) generally involves eradication of Helicobacter pylori. However, MALToma lesions may recur even without H. pylori re-infection. Furthermore, the remission rate of H. pylori-negative MALToma after eradication is low. Therefore, herein, we report on endoscopic submucosal dissection (ESD) as a treatment strategy for gastric MALToma. @*Methods@#We retrospectively reviewed the data of all patients of gastric MALToma who underwent endoscopic resection at our institution between January 2000 and December 2021. Clinical remission was defined as complete histological remission or probable minimal residual disease according to the GELA grading system for post-treatment evaluation of gastric MALToma. @*Results@#Six patients with gastric MALToma underwent ESD. Two patients were diagnosed with gastric MALToma, which improved after eradication treatment and relapsed approximately 36 and 41 months later, respectively. These patients had singular lesions localized to the mucosa and did not experience H. pylori re-infection. The lesions were successfully removed via ESD. The remaining four patients had H. pylori-negative gastric MALToma. These patients also had single, localized lesions that were removed via ESD. All the patients remained in clinical remission until the final follow-up. @*Conclusions@#ESD is a safe and effective intervention for H. pylori-negative gastric MALToma when the lesion is single and confined to the mucosal layer.

Comparison of Helicobacter pylori Eradication Rates Using Standard Triple Therapy and Sequential Therapy

Objectives@#The incidence of treatment failures following standard triple therapy (STT) for Helicobacter pylori eradication (HPE) has reached an unacceptable level. Sequential therapy (SQ) has emerged as a promising approach to counteract the escalation of antibiotic resistance. In this study, we used a chronological cohort dataset to conduct a comparative analysis of the eradication rates, compliance, and adverse events associated with the 7-day STT and SQ. @*Methods@#A total of 789 patients underwent HPE treatment at Asan Medical Center between July 2013 and August 2017. Among them, 378 received a 7-day STT and 411 received a 10-day SQ. Baseline clinical data and treatment parameters were compared between the two treatment groups. @*Results@#SQ demonstrated an eradication rate of 84.7% (348/411), which was superior to that of the 7-day STT (74.1%; p<0.001). The incidence of adverse events was also higher in the SQ group than in the STT group (17.5% vs. 11.1%; p=0.01). Nonetheless, treatment compliance was not significantly different between the groups (98.1% [SQ] vs. 96.8% [STT]; p=0.38). Among the patients undergoing second-line eradication, the SQ group displayed a lower eradication rate than the STT group (77.8% vs. 92.4%; p=0.028). Notably, the overall eradication rate did not differ significantly between the two groups (98.3% [STT] vs. 97.4% [SQ]; p=0.56). @*Conclusions@#SQ exhibited superior efficacy compared with the 7-day STT as a first-line H. pylori treatment. Thus, SQ holds potential to serve as the replacement for the 7-day STT in treatment-naïve patients.

Full mouth rehabilitation using 3D printed crowns and implant assisted removable partial denture for a crossed occlusion: a case report / 대한치과보철학회지

With the recent development of computer-aided design-computer-aided manufacturing technology and 3D printing technology, and the introduction of various digital techniques, the accuracy and efficiency of top-down definitive prosthetic restoration are increasing. In this clinical case, stable occlusion support was obtained through the placement of a total of 9 maxillary and mandibular posterior implants in patient with anterior-posterior crossed occlusion. The edentulous area of the maxillary anterior teeth, which showed a tendency of high resorption of the residual alveolar bone, was restored with a Kennedy Class IV implant assisted removable partial denture to restore soft tissue esthetics. Computed tomography guided surgery was used to place implants in the planned position, double scan technique was used to reflect the stabilized occlusion in the interim restoration stage to the definitive prostheses, and metal 3D printing was used to manufacture the coping and framework. This clinical case reports that efficient and predictable top-down full mouth rehabilitation was achieved using various digital technologies and techniques.

Spontaneous Intracranial Hypotension Treated with Epidural Blood Patch: A Case Report

Spontaneous intracranial hypotension (SIH) is a condition caused by spontaneous cerebrospinal fluid (CSF) leakage, resulting in orthostatic headache as the main symptom, but other symptoms such as memory loss, nausea, and tinnitus may also be present. Various imaging techniques are used to diagnose SIH, with magnetic resonance imaging myelography being an important tool for detecting the leakage site of CSF. Conservative treatments including hydration, bed rest, and intravenous caffeine have been tried with limited success. Epidural blood patch (EBP) is the most commonly performed treatment for SIH after the failure of conservative management. There are different opinions about the EBP procedure (e.g., blind EBP vs. targeted EBP). This report describes the treatment of SIH with targeted EBP according to imaging diagnosis after the failure of initial blind lumbar EBP.

Effectiveness of the COVID-19 vaccine in the Honam region of the Republic of Korea

Objectives@#In 2021, the effectiveness of the COVID-19 vaccine was analyzed among people living in the Honam region (Gwangju, Jeollanam-do, Jeollabuk-do, and Jeju) of the Republic of Korea. And we investigated changes in the dominant virus strain. @*Methods@#This study used the data provided by the Korean Ministry of the Interior and Safety for individuals ≥12 years old in the Honam region, and the Integrated Disease and Health Management System of the Korea Centers for Disease Control and Prevention for COVID-19-vaccinated individuals as of December 31, 2021. Statistical analyzes were performed using IBM SPSS ver. 23.0. The occurrence of confirmed cases by vaccination status, the relative risk, and vaccine effectiveness by vaccine type were calculated. @*Results@#In 2021, the COVID-19 vaccination rate in Honam was 88.6%. The overall vaccine effectiveness (after 2 and 3 doses) was 98.7% (p98%, and the effect among persons who received 2 doses was >90% regardless of the vaccine type. Although vaccine effectiveness decreased because of reduced antibody levels over time (as observed in breakthrough infections), receiving a booster dose restored the neutralizing antibody levels.

Beta Thalassemia Presenting with Neonatal Cholestasis and Extensive Hemosiderosis: A Case Report

Neonatal cholestasis is caused by various forms of liver injury and has a complex etiological background. Among these, cases of severe cholestasis due to primary hemolytic disease are rare. Herein, we report a case in which thalassemia-induced severe hemolysis caused bile duct injury by hemosiderosis, with cholestasis occurring shortly after birth and lasting for >4 months. In addition, complete recovery of liver pathology was observed both biochemically and histologically. Hence, clinicians should consider hemolytic disease as a rare cause of neonatal cholestasis in the differential diagnosis of neonates as well as the advisability of conservative treatment based on case progression.

Validation of Ultrasound and Computed Tomography-Based Risk Stratification System and Biopsy Criteria for Cervical Lymph Nodes in Preoperative Patients With Thyroid Cancer

Objective@#This study aimed to validate the risk stratification system (RSS) and biopsy criteria for cervical lymph nodes (LNs) proposed by the Korean Society of Thyroid Radiology (KSThR). @*Materials and Methods@#This retrospective study included a consecutive series of preoperative patients with thyroid cancer who underwent LN biopsy, ultrasound (US), and computed tomography (CT) between December 2006 and June 2015. LNs were categorized as probably benign, indeterminate, or suspicious according to the current US- and CT-based RSS and the size thresholds for cervical LN biopsy as suggested by the KSThR. The diagnostic performance and unnecessary biopsy rates were calculated. @*Results@#A total of 277 LNs (53.1% metastatic) in 228 patients (mean age ± standard deviation, 47.4 years ± 14) were analyzed. In US, the malignancy risks were significantly different among the three categories (all P 5 mm LNs, P ≥ 0.177). The criteria covering only suspicious LNs showed higher specificity and lower unnecessary biopsy rates than the current criteria, while maintaining sensitivity in all imaging modalities. @*Conclusion@#Integrative evaluation of US and CT helps in reducing the proportion of indeterminate LNs and the malignancy risk among them. Nodal size did not affect the malignancy risk of LNs, and the addition of indeterminate LNs to biopsy candidates did not have an advantage in detecting LN metastases in all imaging modalities.

Comparison of Sleep Quality between Families of Dementia Patients and General Population in Community: Analysis with the Korea Community Health Survey

Background@#This study aimed to examine the difference of sleep quality between family members of dementia patients and general population in community. @*Methods@#Participants (n=215,676) aged 19 years and over in the 2018 Korea Community Health Survey were classified into three groups; family members living at home with a person with dementia (FHD; n=2,445), family members living separately from a person with dementia (FSD; n=9,132), and family members without a person with dementia in the family (FwoD; n=204,099). The Pittsburgh Sleep Quality Index greater than 6 points was regarded as poor sleep quality (PSQ). Multiple logistic regression analysis was used to explore the associations between living with dementia patients and PSQ. @*Results@#The prevalence of PSQ was 48.3% in FHD, 40.7% in FSD, and 38.8% in FwoD. After adjusting for potential confounders, compared to FwoD, the odds ratio for PSQ was 1.42 (95% confidence interval [CI], 1.31-1.54) in FHD and 1.22 (95% CI, 1.17-1.27) in FSD. Additionally, almost all age- and sex-stratified family of dementia patients, except for the youngest (<40 years) men of FHD and the youngest (<40 years) men of FSD, had a higher risk for PSQ than FwoD. @*Conclusions@#Both FHD and FSD have lower sleep quality than FwoD. Public psychological interventions and supports are needed to family members of dementia patients in the community.

Association Between Plasma Homocysteine Level and Mortality:A Mendelian Randomization Study

Background and Objectives@#In previous studies, high homocysteine levels were associated with high cardiovascular mortality. However, these results were inconsistent with those of randomized controlled trials. We aimed to evaluate the causal role of homocysteine on allcause and cardiovascular mortality using Mendelian randomization (MR) analysis. @*Methods@#This study included the 10,005 participants in the Namwon Study. In conventional observational analysis, age, sex, survey years, lifestyles, body mass index, comorbidities, and serum folate level were adjusted using multivariate Cox proportional regression. MR using 2-stage least squares regression was used to evaluate the association between genetically predicted plasma homocysteine levels and mortality. Age, sex, and survey years were adjusted for each stage. The methylenetetrahydrofolate reductase (MTHFR) polymorphism was used as an instrumental variable for predicting plasma homocysteine levels. @*Results@#Observed homocysteine levels were positively associated with all-cause (hazard ratio [HR], 1.40; 95% confidence interval [CI], 1.26–1.54) and cardiovascular (HR, 1.62; 95% CI, 1.28–2.06) mortality when plasma homocysteine levels doubled. However, these associations were not significant in MR analysis. The HRs of doubling genetically predicted plasma homocysteine levels for all-cause and cardiovascular mortality were 0.99 (95% CI, 0.62–1.57) and 1.76 (95% CI, 0.54–5.77), respectively. @*Conclusions@#This MR analysis did not support a causal role for elevated plasma homocysteine concentrations in premature deaths.

Association Between Serum Bilirubin and Atrial Fibrillation: A Mendelian Randomization Study

Background and Objectives@#The association between bilirubin and atrial fibrillation (AF) has been evaluated previously in observational studies but with contradictory results. This study evaluated the causal association between serum bilirubin level and AF using Mendelian randomization (MR) analysis. @*Methods@#This cross-sectional study includes 8,977 participants from the Dong-gu Study.In the observational analysis, multivariate logistic regression was performed to evaluate the association between bilirubin and prevalent AF. To evaluate the causal association between bilirubin and AF, MR analysis was conducted by using the UGT1A1 rs11891311 and rs4148323 polymorphisms as instrumental variables. @*Results@#Elevated serum bilirubin levels were associated with an increased risk for AF in observational analysis (total bilirubin: odds ratio [OR], 1.31; 95% confidence interval [95% CI], 1.15–1.48 per 1 standard deviation [SD]; direct bilirubin: OR, 1.31; 95% CI, 1.18–1.46 per 1 SD), whereas the genetically predicted serum bilirubin levels in MR analysis did not show this association (total bilirubin: OR, 1.02; 95% CI, 0.67–1.53 per 1 SD; direct bilirubin: OR, 1.03; 95% CI, 0.61–1.73 per 1 SD). @*Conclusions@#Genetically predicted bilirubin levels were not associated with prevalent AF.Thus, the observational association between serum bilirubin levels and AF may be noncausal and affected by reverse causality or unmeasured confounding.