Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Background and Objectives: The Fractional Flow Reserve and Intravascular UltrasoundGuided Intervention Strategy for Clinical Outcomes in Patients with Intermediate Stenosis (FLAVOUR) trial demonstrated non-inferiority of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) compared with intravascular ultrasound (IVUS)-guided PCI. We sought to investigate the cost-effectiveness of FFR-guided PCI compared to IVUS-guided PCI in Korea. Methods: A 2-part cost-effectiveness model, composed of a short-term decision tree model and a long-term Markov model, was developed for patients who underwent PCI to treat intermediate stenosis (40% to 70% stenosis by visual estimation on coronary angiography).The lifetime healthcare costs and quality-adjusted life-years (QALYs) were estimated from the healthcare system perspective. Transition probabilities were mainly referred from the FLAVOUR trial, and healthcare costs were mainly obtained through analysis of Korean National Health Insurance claims data. Health utilities were mainly obtained from the Seattle Angina Questionnaire responses of FLAVOUR trial participants mapped to EQ-5D. Results: From the Korean healthcare system perspective, the base-case analysis showed that FFR-guided PCI was 2,451 U.S. dollar lower in lifetime healthcare costs and 0.178 higher in QALYs compared to IVUS-guided PCI. FFR-guided PCI remained more likely to be cost-effective over a wide range of willingness-to-pay thresholds in the probabilistic sensitivity analysis. Conclusions Based on the results from the FLAVOUR trial, FFR-guided PCI is projected to decrease lifetime healthcare costs and increase QALYs compared with IVUS-guided PCI in intermediate coronary lesion, and it is a dominant strategy in Korea.

Background/Aims: Exercise is a key component of the management of axial spondyloarthritis (axSpA), providing symptomatic relief and helping prevent ankylosis. However, there is a lack of quantitative studies evaluating daily exercise patterns in patients with axSpA. This study assessed the types, frequency, and duration of exercises performed by these patients through a structured questionnaire. Methods: This cross-sectional study included radiographic axSpA patients who visited a rheumatology clinic between September 2014 and March 2016 and provided informed consent to participate. The survey captured information on four types of exercise: high-intensity exercise, moderate-intensity exercise, strength training, and walking. Disease activity and functional status were evaluated using the Bath ankylosing spondylitis disease activity index (BASDAI) and the Bath ankylosing spondylitis functional index (BASFI), respectively. Results: A total of 645 patients participated in the study. Among them, 25.1% engaged in high-intensity exercise, 36.0% in moderate-intensity exercise, 81.2% in walking, and 32.8% in strength training. The median weekly exercise frequency was 3.0 days (interquartile range [IQR], 2.0-4.0) for high-intensity exercise, 3.0 days (IQR, 2.0-5.0) for moderate-intensity exercise, 5.5 days (IQR, 4.0-7.0) for walking, and 3.0 days (IQR, 2.0-5.0) for strength training. The median daily exercise duration was 60 minutes (IQR, 60-120) for high-intensity exercise, 60 minutes (IQR, 30-90) for moderate-intensity exercise, 30 minutes (IQR, 20-60) for walking, and 30 minutes (IQR, 20-60) for strength training. Comparisons by disease activity showed that BASFI scores were more strongly associated with differences in exercise patterns than BASDAI scores. Conclusion Radiographic axSpA patients predominantly engaged in low-intensity activities, particularly walking, typically for short durations. Given the observed variations in exercise patterns based on disease activity, personalized exercise education and guidance should be prioritized in clinical practice to optimize axSpA management.

Objective: Ankylosing spondylitis (AS) is chronic inflammatory arthritis causing structural damage and radiographic progression to the spine due to repeated and continuous inflammation over a long period. This study establishes the application of machine learning models to predict radiographic progression in AS patients using time-series data from electronic medical records (EMRs). Methods: EMR data, including baseline characteristics, laboratory findings, drug administration, and modified Stoke AS Spine Score (mSASSS), were collected from 1,123 AS patients between January 2001 and December 2018 at a single center at the time of first (T1 ), second (T2 ), and third (T3 ) visits. The radiographic progression of the (n+1)th visit (Pn+1 =(mSASSSn+1 –mSASSSn )/(Tn+1 – Tn )≥1 unit per year) was predicted using follow-up visit datasets from T1 to Tn . We used three machine learning methods (logistic regression with the least absolute shrinkage and selection operation, random forest, and extreme gradient boosting algorithms) with three-fold cross-validation. Results: The random forest model using the T1 EMR dataset best predicted the radiographic progression P2 among the machine learning models tested with a mean accuracy and area under the curves of 73.73% and 0.79, respectively. Among the T1 variables, the most important variables for predicting radiographic progression were in the order of total mSASSS, age, and alkaline phosphatase. Conclusion Prognosis predictive models using time-series data showed reasonable performance with clinical features of the first visit dataset when predicting radiographic progression.

Objective: Although nonsteroidal anti-inflammatory drugs (NSAIDs) are the first-line treatment for ankylosing spondylitis (AS), their effect on kidney function remains unclear. This longitudinal study investigated the correlation between long-term NSAID use and kidney function in patients with AS using electronic medical records. Methods: The electronic medical records of 1,280 patients with AS collected from a single center between January 2001 and December 2018 were reviewed. The Assessment of Spondyloarthritis International Society (ASAS) NSAID Intake Score was used to determine the cumulative dose of all NSAIDs prescribed for a different time intervals. Each ASAS NSAID Intake Score was obtained for intervals of 6 months, 1 year, 2 years, 3 years, 5 years, and 10 years. The correlation between the ASAS NSAID Intake Score and final estimated glomerular filtration rate (eGFR) for each interval was investigated. Results: The mean ASAS Intake Scores for 6-month, 1-year, 2-year, 3-year, 5-year, and 10-year intervals were 55.30, 49.28, 44.84, 44.14, 44.61, and 41.17, respectively. At each interval, the pearson correlation coefficients were −0.018 (95% CI: −0.031 to −0.006, p=0.004), −0.021 (95% CI: −0.039 to −0.004, p=0.018), −0.045 (95% CI: −0.071 to −0.019, p=0.001), −0.069 (95% CI: −0.102 to −0.037, p<0.001), −0.070 (95% CI: −0.114 to −0.026, p=0.002), −0.019 (95% CI: −0.099 to 0.062, p=0.645), respectively. There was a very weak negative relationship between ASAS Intake Score and eGFR at each interval. Conclusion Long-term NSAID use did not correlate with kidney function based on real-world data in patients with AS.