Factors for achieving target serum uric acid levels after initiating urate-lowering therapy in patients with gout: results from the ULTRA registry

Achieving target serum uric acid (SUA) levels is important in gout management. Guidelines recommend lowering SUA levels to < 6 mg/dL; however, many patients fail to reach this target, even with uric acid-lowering therapy (ULT). This study investigated clinical characteristics of target SUA achievers among Korean patients with gout. This study used data from the ULTRA registry, a nationwide inception cohort established in September 2021 that enrolls patients with gout who initiate ULT. Demographic, clinical, and laboratory data were collected at baseline; the 6-month follow-up. Patients were divided into two groups: target achievers (SUA level < 6 mg/dL at 6 months) and non-achievers. The mean participant (N = 117) age was 56.1 years, and 88.0% were male. At 6 months, 83 patients (70.9%) reached target SUA levels. Target achievers had better drug adherence (≥ 80%) to ULT (97.6% vs. 76.5%; p < 0.01) than non-achievers. Target non-achievers had a higher percentage of a family history of gout (32.4% vs. 10.8%; p < 0.01) and less antihypertensive agent use (38.2% vs. 59.0%; p = 0.03) than target achievers. Multivariate regression analysis revealed that good adherence to ULT, the absence of a family history of gout, and antihypertensive agent use were key factors associated with achieving target SUA levels at 6 months.

Trends in hospital visits and healthcare costs of gout and seropositive rheumatoid arthritis in Korea from 2010 to 2017 using National Healthcare Claims

BACKGROUND/AIMS

We examined temporal trends in the rate of gout and seropositive rheumatoid arthritis (RA) hospital visits and healthcare costs in Korea.

METHODS

We conducted a serial cross-sectional analysis of Korean national healthcare claims. We calculated the annual increase in hospital visits (emergency department [ED] visits, outpatient visits, and hospitalizations) and total healthcare costs per visit.

RESULTS

From 2010 to 2017, the annual rates of ED visits, outpatient visits, and hospitalizations for gout increased from 6.28 to 21, from 638.38 to 1059.55, and from 12.37 to 15.6 per 100,000 persons, respectively. Before 2013, ED visits for gout were most common in patients over 70 years old, but they were most common in those aged between 30 and 49 years after 2013. The number of patients with ED visits, outpatient visits, and hospitalizations for RA from 2010 to 2017 increased from 1.25 to 1.87, from 219.04 to 307.49 and from 8.44 to 12.32 per 100,000 persons, respectively. However, there was no increase in the prevalence of ED visits for RA in any age group except for those older than 70 years. The cost per ED visit for gout significantly decreased from 496.3 to 273.6 US dollar during the study period. There was no significant change in the cost per ED visit for RA between 2010 and 2017.

CONCLUSION

There was a large increase in ED visits for gout during the study period. Further studies are needed to analyze the reason behind increased ED visits for gout and suggest ways on how to improve gout care.

Association of body composition with disease activity and disability in rheumatoid arthritis

BACKGROUND/AIMS

To explore the associations between body composition and pain, disease activity, and disability in rheumatoid arthritis (RA).

METHODS

The study enrolled 335 patients with RA and underwent body composition measurement with an InBody analyzer. The associations of body mass index (BMI), body fat mass, and skeletal muscle mass with disease activity score in 28 joints (DAS28), an index derived to measure the subjective component of DAS28 (DAS28-P), a pain visual analogue scale (VAS), and disability measured with the health assessment questionnaire (HAQ) were explored. Obesity was defined as BMI ≥ 25 kg/m2.

RESULTS

The median (interquartile range) disease duration was 6 years (3.5 to 9) and the mean DAS28 score was 3.6 ± 1.1. The mean BMI was 23.6 ± 3.6 kg/m2 and 109 patients (32.5%) were obese. Compared with non-obese patients, obese patients had a higher C-reactive protein (1.68 mg/dL vs. < 0.1 mg/dL, p = 0.013), higher pain VAS score (40 vs. 35, p = 0.031), and higher DAS28-erythrocyte sedimentation rate score (3.75 ± 1.18 vs. 3.46 ± 1.11, p = 0.031). In multivariate regression analysis, the DAS28 score in females was positively associated with the current steroid dose, body fat mass, and HAQ score, while the HAQ score in females was associated with older age, DAS28, lower skeletal muscle mass, and higher body fat/skeletal muscle ratio. In the multivariate regression analysis, the DAS28-P score in females was positively associated with body fat/skeletal muscle ratio and HAQ.

CONCLUSION

Body composition, such as the body fat mass and body fat/skeletal muscle ratio, is significantly associated with disease activity and disability in female RA patients.

Absence of pain in subjects with advanced radiographic knee osteoarthritis

Background

To investigate the frequency of pain among subjects with advanced radiographic knee osteoarthritis (OA) defined as Kellgren–Lawrence (KL) grade 4 and clinical features associated with pain.

Methods

Subjects from the Hallym Aging Study (HAS), the Korean National Health and Nutrition Examination Survey (KNHANES), and the Osteoarthritis Initiative (OAI) were included. Participants were asked knee-specific questions regarding the presence of knee pain. Clinical characteristics associated with the presence of pain were evaluated with multivariable logistic regression analysis.

Results

The study population consisted of 504, 10,152 and 4796 subjects from HAS, KNHANES, and OAI, respectively. KL grade 4 OA was identified in 9.3, 7.6, and 11.5% of subjects, while pain was absent in 23.5, 31.2, and 5.9% of subjects in KL grade 4 knee OA, respectively. After multivariable analysis, female gender showed a significant association with pain in the KNHANES group, while in the OAI group, younger age did. Advanced knee OA patients without pain did not differ from non-OA subjects in most items of SF-12 in both Korean and OAI subjects. Total WOMAC score was not significantly different between non-OA and advanced knee OA subjects without pain in the OAI.

Conclusions

Our study showed that a considerable number of subjects with KL grade 4 OA did not report pain. In patients whose pain arises from causes other than structural damage of the joint, therapeutic decision based on knee X-ray would lead to suboptimal result. In addition, treatment options focusing solely on cartilage engineering, should be viewed with caution.

Development of a Mouse Model of Knee Osteoarthritis Based on Obesity and Bipedal Walking

To investigate the influence of obesity and obligatory bipedal walking on osteoarthritis (OA) development, 26-week-old C57BL/6 mice were divided into two groups and obesity was induced in one group with a 60% fat diet. After 8 weeks, mice from each group were again divided into two groups and obligatory bipedal exercise was induced with a specially designed treadmill in one group, resulting in four experimental groups (control, control bipedal, obese, and obese bipedal). After 8, 10, and 12 weeks of bipedal walking, knee joints were obtained and graded. Surface fibrillation and matrix proteoglycan depletion, began to appear after 8 weeks of exercise in the bipedal groups and progressed as the duration of the exercise increased. At 12 weeks, cartilage loss extending >75% of articular cartilage was observed in none of the control and obese groups, and in 42.8% and 77.7% of control bipedal and obese bipedal animals, respectively. OA grading was significantly higher in the obese bipedal group compared with the control bipedal group. The von Frey fiber test thresholds decreased significantly in the bipedal groups compared with the control and obese groups. This model can be used to study the pathogenesis of human OA and to evaluate its therapeutic agents. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2411-2419, 2019.

Comparative efficacy of biological agents in methotrexate-refractory rheumatoid arthritis patients: a Bayesian mixed treatment comparison

BACKGROUND/AIMS

Biological agents (biologics) targeting proinflammatory signaling have emerged as an important treatment option in rheumatoid arthritis (RA). Despite the clinical effectiveness of biologics for patients with RA who do not respond to 'traditional' disease-modifying anti-rheumatic drugs (DMARDs), there are concerns regarding their cost and long-term safety. In this study, we aimed to compare the efficacy of various biologics and traditional DMARDs in RA patients refractory to methotrexate (MTX).

METHODS

Four DMARDs (hydroxychloroquine, sulfasalazine, MTX, lef lunomide) and five anti-tumor necrosis factor drugs (adalimumab, etanercept, golimumab, inf liximab, and certolizumab) were selected. A systematic search of published studies was performed from inception through July 2013. Randomized trials of adults with MTX-refractory RA comparing two or more of the selected medications were included. Among 7,938 titles identified, in total, 16 head-to-head trials were selected. Two reviewers independently abstracted the study data and assessed methodological quality using the Cochrane Risk of Bias. Comparative efficacy was analyzed using a Bayesian mixed treatment comparison (MTC).

RESULTS

In total, 9, 4, and 11 studies were included for the outcome measures of the Health Assessment Questionnaire (HAQ), Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR) < 2.6 (remission), and American College of Rheumatology (ACR) 70 response, respectively. The treatments with the highest efficacy for each outcome measure were certolizumab combined with MTX, golimumab combined with MTX, and certolizumab combined with MTX, respectively.

CONCLUSIONS

Based on MTC analysis, using data from published randomized controlled trials, certolizumab and golimumab combined with MTX showed the highest efficacy in the three outcome measures (HAQ, DAS28-ESR < 2.6, and ACR 70 response) in MTX-refractory RA patients.

Prevalence and risk factor of neck pain in elderly Korean community residents

Neck pain is a common musculoskeletal condition, which causes substantial medical cost. In Korea, prevalence of neck pain in community based population, especially in elderly subjects, has scarcely been reported. We evaluated the prevalence, the severity and the risk factors of neck pain in elderly Korean community residents. Data for neck pain were collected for 1,655 subjects from a rural farming community. The point, 6-months and cumulative lifetime prevalence of neck pain was obtained in addition to the measurement of the severity of neck pain. The mean age of the study subjects was 61 yr and 57% were females. The lifetime prevalence of neck pain was 20.8% with women having a higher prevalence. The prevalence did not increase with age, and the majority of individuals had low-intensity/low-disability pain. Subjects with neck pain had a significantly worse SF-12 score in all domains except for mental health. The prevalence of neck pain was significantly associated with female gender, obesity and smoking. This is the first large-scale Korean study estimating the prevalence of neck pain in elderly population. Although the majority of individuals had low-intensity/low-disability pain, subjects with neck pain had a significantly worse SF-12 score indicating that neck pain has significant health impact.

Characteristics of patients with rheumatoid arthritis in clinical remission: the many aspects of DAS28 remission

OBJECTIVES

The aim of this study was to observe the clinical characteristics, including the extent of foot and ankle involvement, of Korean patients with rheumatoid arthritis (RA) in remission, defined as Disease Activity Score in 28 joints (DAS28) <2.6.

METHODS

Data from a registry of RA patients who visited a rheumatology clinic of a university-affiliated hospital and who were regularly evaluated with DAS28, including the ankle and foot metatarsophalangeal (MTP) joints were enrolled. Patients who were treated with disease-modifying anti-rheumatic drugs for at least three months and who were in DAS28 remission were included in this study.

RESULTS

Two hundred and thirteen episodes of DAS28 remission were observed in 147 patients. The mean DAS28 value at the time of remission was 1.84 (range, 0.14-2.59). The mean numbers of swollen joints and tender joints (of the 28 joints examined for DAS28) at the time of remission was 0.4 (range, 0-6) and 1.5 (range, 0-13), respectively. Overall, 11.7% and 38% of the patients in clinical remission had foot MTP/ankle swollen and tender joints, respectively. Additionally, 7% and 8.9%, respectively, of the patients in clinical remission had foot MTP/ankle swollen and tender joints without any involvement of the 28 joints included in the DAS28.

CONCLUSIONS

Our results show that RA patients in DAS28 remission frequently have residual disease activity in the ankle and foot joints. Given that fore-foot disease activity can lead to joint damage and disability with respect to weight-bearing activities, these joints should be included in the clinical examination.