Daehoon Kim

Clinical implication of an impaired fasting glucose and prehypertension related to new onset atrial fibrillation in a healthy Asian population without underlying disease: a nationwide cohort study in Korea

Aims For healthy populations without comorbidities, whether prehypertension and impaired fasting glucose (IFG) are associated with new onset atrial fibrillation (AF) is not well known. Methods and results We included 366 507 subjects (age ≥20 years) not diagnosed with non-valvular AF from the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) from 2003 to 2008. In total, 139 306 subjects diagnosed with AF-related comorbidities were excluded, and a 227 102 healthy population was followed up until 2013. The body mass index (BMI), blood pressure (BP), and fasting blood glucose (BG) level were acquired during National health check-ups. Subjects with IFG [hazard ratio (HR) 1.16, P = 0.017] had a higher AF risk and the diastolic BP (HR 1.11, P = 0.045) was a stronger indicator for an AF incidence than the systolic BP. After dividing the subjects into two mutually exclusive groups, AF incidence was increased dramatically by the combination effect of both prehypertension and an IFG in BMI <25 kg/m2 group, but, in BMI ≧25 kg/m2 group, did not show this tendency. An IFG related to AF risk was more prominent in the BMI <25 kg/m2 population (HR 1.18, P = 0.025) than those with a BMI ≥25 kg/m2, and subjects with both an IFG and prehypertension had a greater AF risk (HR 1.27, P = 0.016) than those without. Conclusion Even in a healthy Asian populations without comorbidities, prehypertension and IFG were important risk factors of AF. Specifically, when prehypertension, including systolic and diastolic BPs, was finally combined with the IFG, the risk of new onset AF was increased especially in the BMI <25 kg/m2 group.

CHA2DS2-VASc Score for Identifying Truly Low-Risk Atrial Fibrillation for Stroke: A Korean Nationwide Cohort Study

Background and Purpose— As the threshold of stroke risk for initiating oral anticoagulants is lowered after the introduction of the nonvitamin K antagonist oral anticoagulants, the focus of stroke prevention in patients with nonvalvular atrial fibrillation has shifted away from predicting high-risk patients toward initially identifying patients with a truly low risk of ischemic stroke, who do not need antithrombotic therapy. We tested the predictive ability of the congestive heart failure, hypertension, age ≥75, diabetes mellitus, prior stroke or transient ischemic attack (doubled; CHADS2), congestive heart failure, hypertension, age ≥75 (doubled), diabetes mellitus, prior stroke or transient ischemic attack (doubled), vascular disease, age 65 to 74, female (CHA2DS2-VASc), and Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) risk stratification schemes in oral anticoagulants naive patients with atrial fibrillation in a Korean nationwide sample cohort. Methods— From January 2002 to December 2008, a total of 5855 oral anticoagulant naive patients with nonvalvular atrial fibrillation aged ≥20 years were enrolled from Korea National Health Insurance Service-Sample Cohort database and were followed-up until December 2013. Results— At baseline, the proportions categorized as low risk using CHADS2, CHA2DS2-VASc, and ATRIA risk stratification schemes were 1049 (17.9%), 860 (14.7%), and 3280 (56.0%), respectively. During follow-up, the low-risk category using CHADS2, CHA2DS2-VASc, and ATRIA scores was retained in 811 (13.9%), 667 (11.4%), and 2729 (46.6%) patients, respectively. Rates of ischemic stroke (100 person-years) in the low risk categories of CHADS2, CHA2DS2-VASc, and ATRIA scores were 0.42, 0.26, and 1.43, respectively. CHA2DS2-VASc had the best sensitivity (98.8% versus 85.7% in CHADS2 and 74.8% in ATRIA) and negative predictive value (98.8% versus 95.3% for CHADS2 and 93.7% for ATRIA) for the prediction of stroke incidence and was best for the prediction of the absence of ischemic stroke during 5 years of follow-up (odds ratio, 16.4 [95% confidence interval, 8.8–30.8]). Conclusions— The CHA2DS2-VASc score shows good performance in defining truly low-risk Asian patients with atrial fibrillation for stroke compared with CHADS2 and ATRIA scores.

Increasing trends in hospital care burden of atrial fibrillation in Korea, 2006 through 2015

Objective Temporal changes in the healthcare burden of atrial fibrillation (AF) are less well known in rapidly ageing Asian countries. We examined trends in hospitalisations, costs, treatment patterns and outcomes related to AF in Korea. Methods Using the National Health Insurance Service (NHIS) database involving the entire adult Korean population (n=41 701 269 in 2015), we analysed a nationwide AF cohort representing 931 138 patients with AF. We studied all hospitalisations due to AF from 2006 to 2015. Results Overall, hospitalisations for AF increased by 420% from 767 to 3986 per 1 million Korean population from 2006 to 2015. Most admissions occurred in patients aged ≥70 years, and the most frequent coexisting conditions were hypertension, heart failure and chronic obstructive pulmonary disease. Hospitalisations mainly due to major bleeding and AF control increased, whereas hospitalisations mainly due to ischaemic stroke and myocardial infarction decreased. The total cost of care increased even after adjustment for inflation from €68.4 million in 2006 to €388.4 million in 2015, equivalent to 0.78% of the Korean NHIS total expenditure. Overall in-hospital mortality decreased from 7.5% in 2006 to 4.3% in 2015. The in-hospital mortality was highest in patients ≥80 years of age (7.7%) and in patients with chronic kidney disease (7.4%). Conclusions AF hospitalisations have increased exponentially over the past 10 years in Korea, in association with an increase in comorbid chronic diseases. Mortality associated with AF hospitalisations decreased during the last decade, but hospitalisation costs have markedly increased.

Remnant Pacemaker Lead Tips after Lead Extractions in Pacemaker Infections

Complete hardware removal is recommended in the case of patients with cardiovascular implantable electronic device (CIED) infections. However, the complete extraction of chronically implanted leads is not always achieved. The outcomes and optimal management of CIED infections with retained material after lead extractions have not been elucidated. In this case report, we present five patients with CIED infections with remnant lead tips even after lead extractions. Two patients had localized pocket infections, and were managed with antibiotics for a period of more than two weeks. The other three patients had infective endocarditis, and were managed with antibiotics for a period of more than four weeks. In one patient, the lead tip migrated to the right pulmonary artery, but did not produce any symptoms or complications. Only one of five patients experienced a resurgence of an infection.

Variations of Prevalence and Incidence of Atrial Fibrillation and Oral Anticoagulation Rate According to Different Analysis Approaches

The reported incidence and prevalence of atrial fibrillation (AF) has been inconsistent across published studies. Using the National Health Insurance Service database of Korea, the prevalence and incidence of AF, and oral anticoagulation (OAC) use of AF patients were explored according to three different approaches; ‘formal approach’, considering individual AF diagnosis and mortality; ‘limited diagnosis approach’, using upper 5 main diagnosis; and ‘medical use approach’, using the number of medical use AF population by year without considering individual AF history and mortality. The AF prevalence progressively increased by 2.46-fold from 0.50% in 2004 to 1.54% in 2015 when using a ‘formal approach’ (p for trend <0.001). The overall prevalence was 1.09% and 0.97% when using a ‘formal approach’ and ‘limited diagnosis approaches’, respectively. Overall prevalence decreased to 0.52% with a ‘medical use approach’. The trend of annual AF incidence was stable when using a ‘formal approach’, but increased by 15% when using a ‘medical use approach’. OAC rate in 2015 was 2.1 times higher when using a ‘medical use approach’ compared to using a ‘formal approach’ (40.3% vs. 19.1%, p < 0.001). Given the wide variability in prevalence and incidence figures with different analysis approaches, careful attention to the analysis methodology is needed.

Effect of Atrial Fibrillation on the Incidence and Outcome of Osteoporotic Fracture ― A Nationwide Population-Based Study ―

BACKGROUND Both atrial fibrillation (AF) and osteoporosis are common in older adults. The purpose of this study was to investigate whether comorbid AF in patients with osteoporosis is associated with fracture incidence, or death after fracture.Methods and Results:From the National Health Insurance Service database of Korea, we selected 31,778 patients with osteoporosis. During a median follow-up of 48 months, the incidence of bone fractures was higher in AF patients than in non-AF patients (3.20 vs. 2.18 per 100 person-years), respectively. In the multivariate Cox regression analysis, AF was associated with fracture independently of other risk factors with an adjusted hazard ratio (HR) of 1.21 (95% confidence interval [CI], 1.02-1.41; P=0.031). The mortality rate after fracture was significantly higher in AF patients than it was in non-AF patients (adjusted HR, 1.92; 95% CI, 1.35-3.27; P=0.016). After propensity score-matching, AF was consistently associated with a higher risk of osteoporotic fracture and subsequent death after fracture. In AF patients, older age, female sex, being underweight (body mass index <18.5 kg/m2), decreased physical activity (exercise <3 times/week), history of stroke or transient ischemic attack, thiazide use, sedative use, and higher CHADS2(≥2 points) or CHA2DS2-VASc (≥2 points) scores were associated with the incidence of fractures. CONCLUSIONS Comorbid AF in patients with osteoporosis was associated with an increased risk of bone fracture and death after fracture.

10-year nationwide trends of the incidence, prevalence, and adverse outcomes of non-valvular atrial fibrillation nationwide health insurance data covering the entire Korean population

Background Most data on the clinical epidemiology of atrial fibrillation (AF) are reported from Western populations, and data for Asians are limited. We aimed to investigate the 10‐year trends of the prevalence and incidence of non‐valvular AF and provide prevalence projections till 2060 in Korea. We also investigated the annual risks of adverse outcomes among patients with AF. Methods Using the Korean National Health Insurance Service database involving the entire Korean population, a total of 679,416 adults with newly diagnosed AF were identified from 2006 to 2015. The incidence and prevalence of AF and risk of adverse outcomes following AF onset were assessed. Results The prevalence of AF progressively increased by 2.10‐fold from 0.73% in 2006 to 1.53% in 2015. The trend of its incidence was flat with a 10‐year overall incidence of 1.77 per 1,000 person‐years. The prevalence of AF is expected to reach 5.81% (2,290,591 patients with AF) in 2060. For a decade, the risk of all‐cause mortality following AF declined by 30% (adjusted hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.68–0.72), heart failure by 52% (adjusted HR: 0.48, 95% CI: 0.44–0.51), and ischemic stroke by 9% (adjusted HR: 0.91, 95% CI: 0.88–0.93). Conclusions The burden of AF among Asian patients is increasing. Although the overall risks of cardiovascular events and death following AF onset have decreased over a decade, the event rates are still high. Optimized management of any associated comorbidities should be part of the holistic management approach for patients with AF.

Cystic Lesion with Sinus Tract and Pathologic Migration of the Third Molar

There are many case reports about cysts within the bones of the jaws associated with impacted third molars. When osmotic pressure is introduced into a cyst, the cyst expands and displaces the third molar. If continuity of cyst wall is lost, cystic expansion cannot occur, and the cyst cannot displace the third molar. This study analyzed four cases of pathologic migration of the third molar in ruptured cystic lesions that had formed bone tunnels and intraoral fistulas to identify the causes and factors contributing to this migration. Authors hypothesized that closure of fistulas repeated generation of pressure, it may temporarily increase the osmotic pressure within a cyst that has lost its continuity, causing displacement of the third molar. A cyst that has lost its continuity due to fistula formation within the oral cavity can cause ectopic displacement of the adjacent impacted teeth.There are many case reports about cysts within the bones of the jaws associated with impacted third molars. When osmotic pressure is introduced into a cyst, the cyst expands and displaces the third molar. If continuity of cyst wall is lost, cystic expansion cannot occur, and the cyst cannot displace the third molar. This study analyzed four cases of pathologic migration of the third molar in ruptured cystic lesions that had formed bone tunnels and intraoral fistulas to identify the causes and factors contributing to this migration. Authors hypothesized that closure of fistulas repeated generation of pressure, it may temporarily increase the osmotic pressure within a cyst that has lost its continuity, causing displacement of the third molar. A cyst that has lost its continuity due to fistula formation within the oral cavity can cause ectopic displacement of the adjacent impacted teeth.

Temporomandibular joint synovial chondromatosis extending to the temporal bone: a report of two cases

Synovial chondromatosis is a rare benign lesion originating from the synovial membrane. It presents as adhesive or non-adhesive intra-articular cartilaginous loose bodies. Although the causes of synovial chondromatosis have not been fully elucidated, inflammation, external injury, or excessive use of joints have been suggested as possible causes. Synovial chondromatosis has been reported to occur most frequently at large joints that bear weights, with a rare occurrence at the temporomandibular joint (TMJ). When synovial chondromatosis develops at TMJ, clinical symptoms, including pain, joint sounds, and mouth opening may common. Moreover, synovial chondromatosis rarely spreads to the mandibular condyle, glenoid cavity, or articular eminence of TMJ. The goal of this study was to discuss the methods of surgery and other possible considerations by reviewing cases of patients who underwent surgery for synovial chondromatosis that extended to the temporal bone.