Association between atrial fibrillation and the risk of glaucoma development: a 12-year Nationwide cohort study.

OBJECTIVE: To investigate the risk of glaucoma development in patients with atrial fibrillation (A-fib) using Korean National Health Insurance Service data. METHODS: The present study used a National Sample Cohort consisting of approximately one million random subjects who were tracked from 2002 to 2013 (12 years). Newly diagnosed glaucoma and A-fib were included based on the Korean Classification of Disease codes. The A-fib group consisted of patients who received an initial A-fib diagnosis between January 2003 and December 2007 as an index period (n = 8765). The control group (n = 43,352) was selected using a 1:5 propensity-score matching for social and demographic factors. Each subject was followed up until 2013. Multivariate Cox proportional hazard regression analysis was performed to compare the risk of glaucoma development between the A-fib group and the control group. RESULTS: The rate of glaucoma development was 3.54% in the A-fib group and 2.96% in the control group (P < 0.0001). A-fib increased the risk of glaucoma development [hazard ratio = 1.31; 95% confidence interval (CI): 1.15 to 1.48] after adjusting for age, sex, comorbidities, residence, household income, and year of enrollment. In multivariable Cox regression analysis, patients with comorbidity of diabetes mellitus and chronic renal failure and those aged ≥50 years showed significantly higher risk of glaucoma development (all P < 0.001). CONCLUSIONS: A-fib was significantly associated with the development of glaucoma after adjusting for potential confounding factors. Physicians may need to monitor patients with A-fib carefully for possible glaucoma development.

A real-world study assessing the impact of retinal fluid on visual acuity outcomes in patients with neovascular age-related macular degeneration in Korea.

To evaluate the real-world treatment outcomes in patients with neovascular age-related macular degeneration (nAMD) in Korea, focusing on retinal fluid resolution. This multi-institutional retrospective chart review study, analyzed medical records of patients with nAMD (age ≥ 50 years) who received their first anti-vascular endothelial growth factor (VEGF) treatment in ophthalmology clinics across South Korea between January 2017 and March 2019. The primary endpoint was the proportion of patients with retinal fluid after 12 months of anti-VEGF treatment. The association between fluid-free period and VA gains was also evaluated. A total of 600 patients were enrolled. At baseline, 97.16% of patients had retinal fluid; after 12 months of anti-VEGF treatment, 58.10% of patients had persistent retinal fluid. VA improvements were relatively better in patients with absence of retinal fluid compared with presence of retinal fluid (+ 12.29 letters vs. + 6.45 letters at month 12; P < .0001). Longer duration of absence of retinal fluid over first 12 months correlated with better VA gains at month 12 (P < .01). More than half of the study patients with nAMD had retinal fluid even after 12 months of treatment with their current anti-VEGF. Presence of retinal fluid was associated with relatively worse VA outcomes.

Clinical Efficacy of Ruxolitinib in Patients with Myelofibrosis: A Nationwide Population-Based Study in Korea.

Previous studies have reported the survival benefit after ruxolitinib treatment in patients with myelofibrosis (MF). However, population-based data of its efficacy are limited. We analyzed the effects of ruxolitinib in MF patients with data from the Korean National Health Insurance Database. In total, 1199 patients diagnosed with MF from January 2011 to December 2017 were identified, of which 731 were included in this study. Patients who received ruxolitinib (n = 224) were matched with those who did not receive the drug (n = 507) using the 1:1 greedy algorithm. Propensity scores were formulated using five variables: age, sex, previous history of arterial/venous thrombosis, and red blood cell (RBC) or platelet (PLT) transfusion dependence at the time of diagnosis. Cox regression analysis for overall survival (OS) revealed that ruxolitinib treatment (hazard ratio (HR), 0.67; p = 0.017) was significantly related to superior survival. In the multivariable analysis for OS, older age (HR, 1.07; p < 0.001), male sex (HR, 1.94; p = 0.021), and RBC (HR, 3.72; p < 0.001) or PLT (HR, 9.58; p = 0.001) transfusion dependence were significantly associated with poor survival, although type of MF did not significantly affect survival. Considering evidence supporting these results remains weak, further studies on the efficacy of ruxolitinib in other populations are needed.

Association Between Chronic Renal Disease and the Risk of Glaucoma Development: A 12-year Nationwide Cohort Study.

Purpose: The purpose of this study was to present the results of our investigation into the risk of glaucoma development in patients with chronic renal disease (CRD). Methods: The present retrospective cohort study used the Korean National Health Insurance Service data, which consisted of 1,025,340 random subjects who were tracked from 2002 to 2013. Newly diagnosed glaucoma and CRD were included on the basis of the Korean Classification of Disease codes. The CRD group consisted of patients who received an initial CRD diagnosis between January 2003 and December 2007 as an index period (n = 3640). The control group (n = 17,971) was selected using 1:5 propensity-score matching using social and demographic factors, along with the year of enrollment. Each group subject was followed until 2013. We used multivariate Cox proportional hazard regression analysis to compare the risk of glaucoma development between the two groups. Results: Glaucoma consecutively developed in 4.3% in the CRD group and 2.8% in the control group (P < 0.0001). CRD increased the risk of glaucoma development (hazard ratio [HR] = 1.63, 95% confidence interval [CI] = 1.34-1.98] after adjusting for age, sex, comorbidities, residence, household income, and the year of enrollment. In multivariate Cox regression analysis, patients with comorbidity of hypertension, diabetes mellitus, or aged ≥ 50 years showed a significantly higher risk of glaucoma development (all P < 0.008). Conclusions: A significant association between CRD and following development of glaucoma was revealed after adjusting the potential confounding factors.

Trends in the Diagnosis and Treatment of Patients with Medullary Thyroid Carcinoma in Korea.

BACKGROUND: Thyroid cancer is becoming increasingly common worldwide, but little is known about the epidemiology of medullary thyroid carcinoma (MTC). This study investigated the current status of the incidence and treatment of MTC using Korean National Health Insurance Service (NHIS) data for the entire Korean population from 2004 to 2016. METHODS: This study included 1,790 MTC patients identified from the NHIS database. RESULTS: The age-standardized incidence rate showed a slightly decreasing or stationary trend during the period, from 0.25 per 100,000 persons in 2004 to 0.19 in 2016. The average proportion of MTC among all thyroid cancers was 0.5%. For initial surgical treatment, 65.4% of patients underwent total thyroidectomy. After surgery, external-beam radiation therapy (EBRT) was performed in 10% of patients, a proportion that increased from 6.7% in 2004 to 11.0% in 2016. Reoperations were performed in 2.7% of patients (n=49) at a median of 1.9 years of follow-up (interquartile range, 1.2 to 3.4). Since November 2015, 25 (1.4%) patients with MTC were prescribed vandetanib by December 2016. CONCLUSION: The incidence of MTC decreased slightly with time, and the proportion of patients who underwent total thyroidectomy was about 65%. EBRT, reoperation, and tyrosine kinase inhibitor therapy are additional treatments after initial surgery for advanced MTC in Korea.

Remote blood pressure monitoring and behavioral intensification for stroke: A randomized controlled feasibility trial.

Measuring blood pressure (BP) at home and remote monitoring can improve the patient's adherence to BP control and vascular outcomes. This study evaluated the feasibility of a trial regarding the effects of an intensive mobile BP management strategy versus usual care in acute ischemic stroke patients. A feasibility-testing, randomized, open-labeled controlled trial was conducted. Remote BP measurement, data transmission, storage, and centralized monitoring system were organized through a Bluetooth-equipped sphygmomanometer paired to the participants' smartphones. Participants were randomized equally into intensive management (behavioral intensification to measure BP at home by texting, direct telephone call, or breakthrough visit) and control (usual care) groups. The primary feasibility outcomes were: 1) recruitment time for the pre-specified number of participants, 2) retention of participants, 3) frequency of breakthrough visit calls, 4) response to breakthrough visit call, and 5) proportions satisfying BP measurement criteria. Sixty participants were randomly assigned to the intensive management (n = 31) and control (n = 29) groups, of which 57 participants were included in the primary analysis with comparable baseline characteristics. Recruitment time from the first to the last participant was 350 days, and 95% of randomized participants completed the final visit (intensive, 94%; control, 98%). Eight breakthrough visit calls were made to 7 participants (23%), with complete and immediate responses within 3 ± 4 days. The median of half-day blocks fulfilling the BP measurement criteria per patient were 91% in the intensive group and 83% in the control group (difference, 12.2; 95% confidence interval, 2.2-22.2). No adverse events related to the trial procedures were reported. The intensive monitoring, including remote BP measurement, data transfer, and centralized monitoring system, engaged with behavioral intensification was feasible if the patients complied with the intervention. However, the device utilized would need further improvement prior to a large trial.

Development of stroke identification algorithm for claims data using the multicenter stroke registry database.

BACKGROUND: Identifying acute ischemic stroke (AIS) among potential stroke cases is crucial for stroke research based on claims data. However, the accuracy of using the diagnostic codes of the International Classification of Diseases 10th revision was less than expected. METHODS: From the National Health Insurance Service (NHIS) claims data, stroke cases admitted to the hospitals participating in the multicenter stroke registry (Clinical Research Collaboration for Stroke in Korea, CRCS-K) during the study period with principal or additional diagnosis codes of I60-I64 on the 10th revision of International Classification of Diseases were extracted. The datasets were randomly divided into development and validation sets with a ratio of 7:3. A stroke identification algorithm using the claims data was developed and validated through the linkage between the extracted datasets and the registry database. RESULTS: Altogether, 40,443 potential cases were extracted from the NHIS claims data, of which 31.7% were certified as AIS through linkage with the CRCS-K database. We selected 17 key identifiers from the claims data and developed 37 conditions through combinations of those key identifiers. The key identifiers comprised brain CT, MRI, use of tissue plasminogen activator, endovascular treatment, carotid endarterectomy or stenting, antithrombotics, anticoagulants, etc. The sensitivity, specificity, and diagnostic accuracy of the algorithm were 81.2%, 82.9%, and 82.4% in the development set, and 80.2%, 82.0%, and 81.4% in the validation set, respectively. CONCLUSIONS: Our stroke identification algorithm may be useful to grasp stroke burden in Korea. However, further efforts to refine the algorithm are necessary.

Factors associated with myopia in Korean children: Korea National Health and nutrition examination survey 2016-2017 (KNHANES VII).

BACKGROUND: To evaluate the prevalence and risk factors associated with myopia and high myopia in children in South Korea. METHODS: A total of 983 children 5-18 years of age who participated in the Korean National Health and Nutrition Examination Survey 2016-2017 (KNHANES VII), a nationwide population-based cross-sectional study, were evaluated. Myopia and high myopia were defined as a spherical equivalent (SE) ≤ - 0.5 diopters (D) and SE ≤ --6.0 D. The association between refractive errors and potential risk factors for myopia was analyzed. RESULTS: The prevalence of myopia and high myopia was 65.4 and 6.9%, respectively. Older age and parental myopia were significantly associated with both myopia and high myopia, while higher body mass index (BMI) was associated with high myopia only. Although the proportion of subjects who spent more time on near work activities (≥4 h/day) was sequentially increased with increased refractive error, this tendency was not statistically significant by multivariable logistic regression. CONCLUSIONS: Korean children had a high prevalence of myopia and high myopia. In this age group, the risk of myopia increased with aging and parental myopia. Higher BMI may be associated with high myopia.

The Epidemiology of Fracture in Patients with Acute Ischemic Stroke in Korea.

BACKGROUND: Patients who survive an acute phase of stroke are at risk of falls and fractures afterwards. However, it is largely unknown how frequent fractures occur in the Asian stroke population. METHODS: Patients with acute (< 7 days) ischemic stroke who were hospitalized between January 2011 and November 2013 were identified from a prospective multicenter stroke registry in Korea, and were linked to the National Health Insurance Service claim database. The incidences of fractures were investigated during the first 4 years after index stroke. The cumulative incidence functions (CIFs) were estimated by the Gray's test for competing risk data. Fine and Gray model for competing risk data was applied for exploring risk factors of post-stroke fractures. RESULTS: Among a total of 11,522 patients, 1,616 fracture events were identified: 712 spine fractures, 397 hip fractures and 714 other fractures. The CIFs of any fractures were 2.63% at 6 months, 4.43% at 1 year, 8.09% at 2 years and 13.00% at 4 years. Those of spine/hip fractures were 1.11%/0.61%, 1.88%/1.03%, 3.28%/1.86% and 5.79%/3.15%, respectively. Age by a 10-year increment (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.17-1.30), women (HR, 1.74; 95% CI, 1.54-1.97), previous fracture (HR, 1.72; 95% CI, 1.54-1.92) and osteoporosis (HR, 1.44; 95% CI, 1.27-1.63) were independent risk factors of post-stroke fracture. CONCLUSION: The CIFs of fractures are about 8% at 2 years and 13% at 4 years after acute ischemic stroke in Korea. Older age, women, pre-stroke fracture and osteoporosis raised the risk of post-stroke fractures.