Kuo-Tung Tang

Drug trough levels predict therapeutic responses to dose reduction of adalimumab for rheumatoid arthritis patients during 24 weeks of follow-up

OBJECTIVE To evaluate the impact of adalimumab (ADA) dose-halving on therapeutic responses and drug levels, the differences in drug levels among patients with different therapeutic responses and the optimal baseline cut-off ADA levels for predicting persistent remission or low disease activity (LDA) at week 24 of dose-halving therapy in 64 RA patients who had already achieved LDA or remission at baseline. METHODS Anti-ADA antibody levels were determined by bridging ELISA, ADA levels were evaluated using sandwich ELISA and therapeutic responses were assessed by the 28-joint DAS change. The optimal cut-off drug levels for predicting persistent remission were determined by receiver operating characteristic curve analysis. RESULTS At baseline, 25 (39.1%) and 39 (60.9%) patients had achieved remission and LDA, respectively. After 24 week ADA dose-halving, persistent remission was observed in 23 patients, remission turned LDA in 2 patients, persistent LDA in 24 patients and disease flare in 15 (23.5%) patients. Three patients who developed anti-ADA antibodies at week 24 of dose-halving had very low drug levels and disease flare. Among 61 anti-ADA antibody-negative patients, ADA levels declined by half after 24 weeks of dose-halving (median 5.5 vs 2.6 μg/ml). Baseline ADA levels were significantly higher in patients with persistent remission (median 10.5 μg/ml) or LDA (4.5 μg/ml) than in those with disease flare (0.9 μg/ml), indicating associations of ADA levels with therapeutic responses. An ADA level above the cut-off value of 6.4 μg/ml might predict persistent remission after dose-halving with high sensitivity and specificity. CONCLUSION ADA dose-halving is feasible for patients who have achieved remission and sufficient drug levels. Drug level monitoring may help clinicians optimize the dosing regimen and prevent overtreatment for patients receiving anti-TNF-α therapy.

Adult atopic dermatitis and exposure to air pollutants—a nationwide population-based study

BACKGROUND There is a trend toward an increased worldwide prevalence of allergic diseases. It is speculated that industrialization with resultant air pollution plays a role. However, there are sparse epidemiologic data on the relation between air pollution and atopic dermatitis (AD) in adults. OBJECTIVE To investigate the relation between exposure to air pollutants and adult AD in a cross-sectional study based on data from the National Health Insurance Research Database in Taiwan. METHODS We identified 1,023 adult patients with AD and 4,092 age- and sex-matched controls without allergic diseases in 2011. Using data from 71 Environmental Protection Agency monitoring stations across Taiwan, levels of exposure to air pollutants were determined by the location of a subjects place of residence. Multivariate logistic regression analysis, adjusted for age, sex, levels of urbanization, and family income, was performed. RESULTS We found an association between particulate matter <2.5 μm in diameter or the Pollutant Standards Index (the highest sub-index of the concentrations of 5 main air pollutants after transformation) and the development of adult AD. The adjusted odds ratios were 1.05 (95% confidence interval 1.02-1.08) and 1.02 (95% confidence interval 1.01-1.03), respectively. CONCLUSION These results demonstrated that air pollution, represented by particulate matter <2.5 μm in diameter or the Pollutant Standards Index, was modestly associated with the development of AD in adults.

Suicide attempts in patients with systemic lupus erythematosus: a single-center experience and literature review.

BACKGROUND Suicide is a global health issue, and an increase in suicide risk has been found in patients with systemic lupus erythematosus (SLE) when compared with the general population. However, only a few studies have described suicide attempts in patients with SLE in detail. OBJECTIVE The aim of this study is to describe the suicide attempts in patients with SLE in a tertiary hospital in Taiwan. METHODS A total of 8 patients with SLE, 7 women and 1 man, with 12 suicide attempts among them were identified among 2469 patients visiting a tertiary medical center in Taiwan, from March 1, 2003 to November 30, 2013. Their demographic data, lupus manifestations throughout their disease course, laboratory data, and details of their suicide attempts were retrospectively documented. We also searched the MEDLINE database and found 4 articles in English describing suicide attempts in 14 patients with SLE. RESULTS The median age of the 8 patients with SLE in our hospital who attempted suicide was 33 years (range: 19-77 years). Neuropsychiatric SLE developed in 5 (63%) of these patients before the attempts, and psychiatric disorders were diagnosed in 5 (63%) of them. We also observed a high prevalence of neuropsychiatric SLE (71%) and psychiatric disorders (86%) in patients with SLE in the literature who had attempted suicide. CONCLUSION We demonstrated that previous neuropsychiatric SLE and comorbid psychiatric disorders are prevalent in patients with SLE who attempt suicide. If a rheumatologist suspects that a patient with SLE has a psychiatric disorder, he or she should refer the patient to a psychiatrist.

Elevated Expression of the NLRP3 Inflammasome and Its Correlation with Disease Activity in Adult-onset Still Disease

Objective. The dysregulation of the NLRP3 (NLR containing a pyrin domain) inflammasome is involved in autoinflammatory diseases. Adult-onset Still disease (AOSD) is regarded as an autoinflammatory disease. However, the pathogenic involvement of NLRP3 inflammasome in AOSD remains unclear and NLRP3 activators in AOSD are currently unknown. Methods. The mRNA expression of NLRP3 inflammasome signaling in peripheral blood mononuclear cells (PBMC) from 34 patients with AOSD and 14 healthy subjects was determined using quantitative-PCR (qPCR). The changes in mRNA and protein levels of NLRP3 inflammasome signaling in PBMC treated with the potential activator [imiquimod (IMQ)] or inhibitor of NLRP3 were evaluated using qPCR and immunoblotting, respectively. The supernatant levels of interleukin (IL)-1β and IL-18 were determined by ELISA. Results. Significantly higher mRNA levels of NLRP3 inflammasome signaling were observed in patients with AOSD compared with healthy controls. NLRP3 expressions were positively correlated with disease activity in patients with AOSD. IMQ (an effective Toll-like receptor 7 ligand; 10 µg/ml and 25 µg/ml) stimulation of PBMC from patients with AOSD induced dose-dependent increases of mRNA expression of NLRP3 (mean ± standard error of the mean, 2.06 ± 0.46 and 6.05 ± 1.84, respectively), caspase-1 (1.81 ± 0.23 and 4.25 ± 0.48), IL-1β (5.68 ± 1.51 and 12.13 ± 3.71), and IL-18 (2.32 ± 0.37 and 4.81 ± 0.51) compared with controls (all p < 0.005). IMQ stimulation of PBMC from patients similarly induced greater increases in protein expressions of NLRP3 inflammasome compared with controls. The protein expressions of NLRP3, IL-1β, and IL-18 on PBMC significantly decreased after treatment with NLRP3 inhibitor in patients with AOSD. Conclusion. Increased expression of NLRP3 inflammasome and its positive correlation with disease activity in AOSD suggest its involvement in disease pathogenesis. IMQ upregulated expressions of NLRP3 inflammasome signaling, and IMQ might be an activator of NLRP3 inflammasome in AOSD.

The risk of tuberculosis disease in rheumatoid arthritis patients on biologics and targeted therapy: A 15-year real world experience in Taiwan

The objective of this study is to determine the risk of tuberculosis (TB) disease in biologics users among rheumatoid arthritis (RA) patients in Taiwan from 2000 to 2015. This retrospective cohort study enrolled adult RA patients initiated on first biologics at Taichung Veterans General Hospital. TB risks were determined as hazard ratio (HR) with 95% confidence interval (CI) using cox regression. A total of 951 patients were recruited; etanercept (n = 443), adalimumab (n = 332), abatacept (n = 74), golimumab (n = 60), tocilizumab (n = 31) and tofacitinib (n = 11). Twenty-four TB cases were identified; 13 in etanercept and 11 in adalimumab group with the TB incidence rate of 889.3/ 100,000 and 1055.6/ 100,000 patient-years respectively. There was no significant difference in TB risk between adalimumab and etanercept users with an incidence rate ratio of 1.27 (p = 0.556 by Poisson model). Significant 2-year TB risk factors included elderly patient >65 year-old (HR: 2.72, 95% CI: 1.06–6.99, p = 0.037), history of TB (HR: 6.24, 95% CI: 1.77–22.00, p = 0.004) and daily glucocorticoid use ≥5mg (HR:5.01, 95% CI: 1.46–17.21, p = 0.010). Sulfasalazine treatment appeared to be protective (HR: 0.32, 95% CI: 0.11–0.97, p = 0.043). Risk management plan (RMP) for TB before initiation of biologics commenced in 2012. The 2-year TB risks after RMP was compared with that before 2012 (HR:0.67, 95% CI: 0.30–1.49, p = 0.323). Elderly RA patients with a history of previous TB infection and concomitant moderate dose glucocorticoid were at higher risk of TB disease. Concurrent sulfasalazine treatment appeared to be a protective factor against TB disease.

Methotrexate is not associated with increased liver cirrhosis in a population-based cohort of rheumatoid arthritis patients with chronic hepatitis B

A few studies showed that long-term methotrexate (MTX) use exacerbates liver fibrosis and even leads to liver cirrhosis in rheumatoid arthritis (RA) patients. We therefore conducted a population-based cohort study to investigate the impact of long-term MTX use on the risk of chronic hepatitis B (CHB)-related cirrhosis among RA patients. We analyzed data from the National Health Insurance Research Database in Taiwan and identified 631 incident cases of RA among CHB patients (358 MTX users and 273 MTX non-users) from January 1, 1998 to December 31, 2007. After a median follow-up of more than 6 years since the diagnosis of CHB, a total of 41 (6.5%) patients developed liver cirrhosis. We did not find an increased risk of liver cirrhosis among CHB patients with long-term MTX use for RA. Furthermore, there was no occurrence of liver cirrhosis among 56 MTX users with a cumulative dose ≧3 grams after 97 months’ treatment. In conclusion, our data showed that long-term MTX use is not associated with an increased risk for liver cirrhosis among RA patients with CHB. However, interpretation of the results should be cautious due to potential bias in the cohort.

Suicidal drug overdose in patients with systemic lupus erythematosus, a nationwide population-based case-control study

Objective A four-fold increase of suicide mortality has been demonstrated in systemic lupus erythematosus (SLE) patients. Prior studies showed that the most common method of suicide attempts in SLE patients involves drug overdose. Therefore, we conducted a nationwide population-based case-control study to elucidate factors associated with drug overdose as suicide attempt in SLE patients. Methods This study was based on the National Health Insurance Research Database in Taiwan. We identified all SLE patients from January 1, 2000 to December 31, 2010. Patients who had suicidal drug overdose (SDO) were selected as cases while age- and gender-matched patients who did not have SDO were selected as controls. Results The incidence rate of SDO in SLE patients was 291 cases per 100,000 person-years, higher than that in the general population (160 cases per 100,000 person-years). In a multivariate logistic regression analysis, we observed that SDO was associated with psychiatric disorders such as depressive disorders (odds ratio: 8.36, 95% confidence interval (CI): 5.60–12.48) and insomnia (odds ratio: 2.71, 95% CI: 1.73–4.25), and lower monthly income (odds ratios: 2.74 to 3.50) in SLE patients. Conclusion SDO is associated with psychiatric disorders such as depressive disorders and insomnia, and lower monthly income in SLE patients.

Upregulation of circulating microRNA-134 in adult-onset Still’s disease and its use as potential biomarker

Adult-onset Still’s disease (AOSD) is a multi-systemic inflammatory disorder of unknown etiology. To date, no single diagnostic test is available for AOSD. Herein, we investigated the pathogenic role of microRNAs in AOSD. MicroRNA profiles in plasma from AOSD patients and healthy controls were analyzed by microarray analysis, followed by quantitative reverse transcription PCR validation. The biological functions of microRNAs were evaluated using in vitro cell-based assay. Among the differentially expressed microRNAs, microRNA-134 (miR-134) expression was positively correlated with AOSD activity scores and significantly decreased after effective treatment. An increased miR-134 level is significantly associated with the activation of Toll-like receptor 3 (TLR3). The reporter assay identified IL-18 binding protein (IL-18BP) as the target of miR-134. A negative correlation between miR-134 expression and IL-18BP mRNA levels were detected in peripheral blood cells following TLR3 ligand treatment. Lower plasma IL-18BP levels and higher IL-18 levels were also observed in active AOSD patients who had higher miR-134 expression than inactive patients. Upregulation of circulating miR-134 was associated with elevated IL-18 levels by targeting IL-18BP in AOSD patients and was positively correlated with disease activity, suggesting its involvement in AOSD pathogenesis. MiR-134 may be a novel activity indicator or potential prognostic biomarker in AOSD.

Measuring serum levels of high-mobility group box 1 by enzyme-linked immunosorbent assay does not identify bacterial infections in patients with systemic lupus erythematosus.

Introduction studies have shown that high-mobility group box 1 (HMGB1) may play a role in the propagation of inflammatory response in infectious and autoimmune diseases. However, its utility in the differentiation between infections and disease flares in systemic lupus erythematosus (SLE) patients has not been investigated. Methods we prospectively recruited 38 hospitalized patients from Taiwan with SLE. Among them, 13 patients suffered from superimposed bacterial infections while the other 25 patients experienced disease flares. SLE disease activity was assessed by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Serum levels of HMGB1 were measured by an enzyme-linked immunosorbent assay (ELISA). Additionally, serum levels of high-sensitivity C-reactive protein (hsCRP) were determined among 34 of the SLE patients. Results there was no significant difference between the serum HMGB1 levels in SLE patients with disease flares and patients with bacterial infections. Among SLE patients with disease flares, serum HMGB1 levels were significantly higher in patients with mild to moderate flares (3.53 ng/ml) compared to those with severe flares (1.72 ng/ml, p < 0.05). For identifying bacterial infections in patients with SLE, the area under the receiver operating characteristic (ROC) curve was 0.705 (95% CI: 0.524–0.848) for hsCRP and 0.497 (95% CI: 0.331–0.663) for HMGB1. The best cutoff value for hsCRP was 1.07 mg/dl for detection of bacterial infections in SLE patients, with a sensitivity of 75% and a specificity of 68%. Conclusion the determination of serum HMGB1 level is not useful in the differentiation between disease flares and bacterial infections in SLE patients.

Tolerogenic β2-glycoprotein I DNA vaccine and FK506 as an adjuvant attenuates experimental obstetric antiphospholipid syndrome

DNA vaccines have recently emerged as a therapeutic agent for treating autoimmune diseases, such as multiple sclerosis. Antiphospholipid antibody syndrome (APS) is an autoimmune disease characterized by β2-glycoprotein I (β2-GPI)-targeting antiphospholipid antibodies (APAs) and vascular thrombosis or obstetrical complications. To examine the therapeutic potential of a β2-GPI DNA vaccine, we administered a vaccine mixed with FK506 as an adjuvant to a mouse model of obstetric APS. First, the pCMV3-β2-GPI DNA vaccine, which encodes the full-length human β2-GPI gene, was constructed. Then, we administered the β2-GPI DNA vaccine in 0.1 ml of saline, mixed with or without 100 μg of FK506, intramuscularly to the mice on days 28, 35 and 42. Blood titers of the anti-β2-GPI antibody, platelet counts, activated partial thromboplastin times (aPTTs), and the percentage of fetal loss were measured. We also stimulated murine splenic T cells ex vivo with β2-GPI and determined the T helper cell proportion and cytokine secretion. The administration of the β2-GPI DNA vaccine mixed with FK506 reduced the blood IgG anti-β2-GPI antibody titers and suppressed APS manifestations in mice. The combination also suppressed interferon-γ and interleukin (IL)-17A secretion but increased the Treg cell proportion and IL-10 secretion in murine splenic T cells following ex vivo stimulation with β2-GPI. Our results demonstrated the therapeutic efficacy of a β2-GPI DNA vaccine and FK506 as an adjuvant in a murine model of obstetric APS. Possible mechanisms include the inhibition of Th1 and Th17 responses and the up-regulation of Treg cells.