ObjectiveHealth-related quality of life (HRQOL) in patients with fibromyalgia (FM) is lower than in patients with other chronic diseases and the general population. Although various factors affect HRQOL, no study has examined a structural equation model of HRQOL as an outcome variable in FM patients. The present study assessed relationships among physical function, social factors, psychological factors, and HRQOL, and the effects of these variables on HRQOL in a hypothesized model using structural equation modeling (SEM).MethodsHRQOL was measured using SF-36, and the Fibromyalgia Impact Questionnaire (FIQ) was used to assess physical dysfunction. Social and psychological statuses were assessed using the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Arthritis Self-Efficacy Scale (ASES), and the Social Support Scale. SEM analysis was used to test the structural relationships of the model using the AMOS software.ResultsOf the 336 patients, 301 (89.6%) were women with an average age of 47.9±10.9 years. The SEM results supported the hypothesized structural model (χ2 = 2.336, df = 3, p = 0.506). The final model showed that Physical Component Summary (PCS) was directly related to self-efficacy and inversely related to FIQ, and that Mental Component Summary (MCS) was inversely related to FIQ, BDI, and STAI.ConclusionsIn our model of FM patients, HRQOL was affected by physical, social, and psychological variables. In these patients, higher levels of physical function and self-efficacy can improve the PCS of HRQOL, while physical function, depression, and anxiety negatively affect the MCS of HRQOL.

Objective. Allopurinol-induced severe cutaneous adverse reactions (SCARs) are relatively rare but cause high rates of morbidity and mortality. Studies have shown that the HLA-B5801 allele and renal impairment are strongly associated with SCARs. Recent American College of Rheumatology guidelines recommend that, prior to treatment with allopurinol, the HLA-B5801 genotype of gout patients at high risk for SCARs, including Korean patients with chronic renal insufficiency, should be determined. However, whether such genotyping is cost-effective is unknown. This study evaluated the cost-effectiveness of HLA-B5801 genotyping for the treatment of gout in patients with chronic renal insufficiency in Korea. Methods. A decision analytical model over a time period of 12 months was employed to compare the cost and outcomes of treatment informed by HLA-B5801 genotyping with that of a conventional treatment strategy using a hypothetical cohort of gout patients with chronic renal insufficiency. Direct medical costs were obtained from real patients with SCARs from 2 tertiary hospitals. Outcomes were measured as a total expected cost and an incremental cost-effectiveness ratio. Results. In the base model, the total expected cost and probability of continuation of gout treatment without SCARs for the conventional and HLA-B5801 screening strategies were $1,193 and 97.8% and $1,055 and 100%, respectively. The results were robust according to sensitivity analyses. Conclusion. Our model suggests that gout treatment informed by HLA-B5801 genotyping is less costly and more effective than treatment without genotyping, and HLA-B5801 genotyping could considerably reduce the occurrence of allopurinolinduced SCARs and related deaths.

Aim: To investigate whether patients with Sj€ ogren's syndrome (SS) can be distinguished based on the positivity of anti-centromere antibody (ACA), and if so, whether the subgroups differ in their clinical and laboratory features.Methods: Eleven patients with ACA-positive and 71 patients ACA-negative SS were examined. All patients had minor salivary gland biopsy; sociodemographic data, glandular and extraglandular manifestations, and laboratory findings, including autoantibodies, complement and immunoglobulin levels, were analyzed. European League Against Rheumatism SS disease activity index (ESSDAI) and SS disease damage index (SSDDI) were also measured.Results: The prevalence of ACA among SS patients was 13.4%. ACA-positive SS patients had a higher prevalence of Raynaud's phenomenon, sclerodactyly and autoimmune thyroiditis and a lower prevalence of anti-SSA/Ro and anti-SSB/La antibodies compared to ACA-negative patients. Disease activity was higher in ACA-positive patients than in ACA-negative patients, but the damage index did not differ between the two groups. None of the patients who originally had ACA evolved to having full-blown systemic sclerosis. Conclusion:Patients with SS who have ACA differ from classic SS patients in several clinical and laboratory parameters. ACA should be considered one of the pathogenically relevant autoantibodies for SS.

We investigated the compliance of Korean patients using tumor necrosis factor (TNF) inhibitors to treat rheumatoid arthritis (RA) and ankylosing spondylitis (AS), and identified potential predictors associated with treatment discontinuation. The study population comprised 114 RA and 310 AS patients treated with TNF inhibitors at a single tertiary center for at least 1 yr from December 2002 to November 2011. Of the 114 RA patients, 64 (56.1%) discontinued their first TNF inhibitors with a mean duration of 18.1 months. By contrast, 65 of 310 patients (21.0%) with AS discontinued their first TNF inhibitors, with a mean duration of 84 months. Although the survival rate did not differ among the three TNF inhibitors in the AS patients, the etanercept group had a lower discontinuation rate than the infliximab group in the RA patients. In addition, RA patients who received corticosteroids in combination with TNF inhibitors were more likely to discontinue their TNF inhibitors. The independent predictors of drug discontinuation in AS patients were male gender and complete ankylosis on radiographs of the sacroiliac joint. Our results provide further evidence that real-life treatment outcomes of RA and AS patients may be different from those observed in randomized clinical trials.Graphical Abstract

Our findings suggest that glomerular sclerosis in the chronicity index is an independent predictor of CR after the start of therapy in LN patients.