OP0112 THE EVER-LARGEST ASIAN GWAS FOR SYSTEMIC SCLEROSIS AND TRANS-POPULATION META-ANALYSIS IDENTIFIED SEVEN NOVEL LOCI AND A CANDIDATE CAUSAL SNP IN A CIS-REGULATORY ELEMENT OF THE FCGR REGION

Background

Genome-wide association studies (GWASs) have identified 29 disease-associated single nucleotide polymorphisms (SNPs) for systemic sclerosis (SSc) in non-human leukocyte antigen (HLA) regions (1-7). While these GWASs have clarified genetic architectures of SSc, study subjects were mainly Caucasians limiting application of the findings to Asians.

Objectives

The study was conducted to identify novel causal variants for SSc specific to Japanese subjects as well as those shared with European population. We also aimed to clarify mechanistic effects of the variants on pathogenesis of SSc.

Methods

A total of 114,108 subjects comprising 1,499 cases and 112,609 controls were enrolled in the two-staged study leading to the ever-largest Asian GWAS for SSc. After applying a strict quality control both for genotype and samples, imputation was conducted using the reference panel of the phase 3v5 1,000 genome project data combined with a high-depth whole-genome sequence data of 3,256 Japanese subjects. We conducted logistic regression analyses and also combined the Japanese GWAS results with those of Europeans (6) by an inverse-variance fixed-effect model. Polygenicity and enrichment of functional annotations were evaluated by linkage disequilibrium score regression (LDSC), Haploreg and IMPACT programs. We also constructed polygenic risk score (PRS) to predict SSc development.

Results

We identified three (FCRLA-FCGR, TNFAIP3, PLD4) and four (EOMES, ESR1, SLC12A5, TPI1P2) novel loci in Japanese GWAS and a trans-population meta-analysis, respectively. One of Japanese novel risk SNPs, rs6697139, located within FCGR gene clusters had a strong effect size (OR 2.05, P=4.9×10-11). We also found the complete LD variant, rs10917688, was positioned in cis-regulatory element and binding motif for an immunomodulatory transcription factor IRF8 in B cells, another genome-wide significant locus in our trans-ethnic meta-analysis and the previous European GWAS. Notably, the association of risk allele of rs10917688 was significant only in the presence of the risk allele of the IRF8. Intriguingly, rs10917688 was annotated as one enhancer-related histone marks, H3K4me1, in B cells, implying that FCGR gene(s) in B cells may play an important role in the pathogenesis of SSc. Furhtermore, significant heritability enrichment of active histone marks and a transcription factor C-Myc were found in B cells both in European and Japanese populations by LDSC and IMPACT, highlighting a possibility of a shared disease mechanism where abnormal B-cell activation may be one of the key drivers for the disease development. Finally, PRS using effects sizes of European GWAS moderately fit in the development of Japanese SSc (AUC 0.593), paving a path to personalized medicine for SSc.

Conclusion

Our study identified seven novel susceptibility loci in SSc. Downstream analyses highlighted a novel disease mechanism of SSc where an interactive role of FCGR gene(s) and IRF8 may accelerate the disease development and B cells may play a key role on the pathogenesis of SSc.

References

[1]F. C. Arnett et al. Ann Rheum Dis, 2010.

[2]T. R. Radstake et al. Nat Genet, 2010.

[3]Y. Allanore et al. PLoS Genet, 2011.

[4]O. Gorlova et al. PLoS Genet, 2011.

[5]C. Terao et al. Ann Rheum Dis, 2017.

[6]E. López-Isac et al. Nat Commun, 2019.

[7]W. Pu et al. J Invest Dermatol, 2021.

Disclosure of Interests

None declared

OP0110 CELL-TYPE-SPECIFIC TRANSCRIPTOME ARCHITECTURE UNDERLYING THE ESTABLISHMENT AND EXACERBATION OF SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unknown etiology involving multiple immune cells and has diverse clinical phenotypes. This heterogeneous nature has hampered a better understanding of SLE pathogenesis and the development of effective therapeutic agents. While recent single-cell RNA sequencing studies of SLE identified several important cell subpopulations, they were limited by sparse expression information at single-cell level and small sample sizes.

Objectives

This study aimed to elucidate the dysregulated gene expression pattern linked to multiple clinical statuses of SLE with a fine cellular resolution and higher sensitivity. We also attempted to resolve a complex interaction between risk variants and the transcriptome dysregulation seen in SLE patients.

Methods

We conducted a large-scale bulk transcriptome study of 6,386 RNA-sequencing data including 27 purified immune cell types in peripheral blood from 136 SLE and 89 healthy donors in the Immune Cell Gene Expression Atlas from the University of Tokyo (ImmuNexUT) cohort1. At enrollment, SLE patients had diverse clinical manifestations (disease activity, organ involvement and treatment profiles) and 22 patients were re-evaluated after belimumab treatment.

Results

We first profiled two distinct cell-type-specific transcriptomic signatures: disease-state and disease-activity signatures, reflecting disease establishment and exacerbation, respectively.

After confirming the high replicability of both signatures in independent cohorts, we identified candidates of biological processes unique to each signature: e.g., upregulated E2F transcriptional activity in Th1, CD8+ memory T-lineage and NK cells, and dynamic increase of IL21 and CXCL13 in Th1 cells in an active phase of SLE. Pathway analysis highlighted the importance of immunometabolic process for SLE (e.g., oxidative phosphorylation) in cell-type-specific resolution.

Moreover, we demonstrated cell-type-specific contributions to diverse organ involvement, e.g., Th1 for mucocutaneous, monocyte-lineage cells for musculoskeletal, neutrophil-lineage cells for renal activity, respectively.

We also observed the strong associations of disease-activity signatures with treatment effect: (i) belimumab suppressed activity signatures from B-lineage cells, especially in good responders and (ii) mycophenolate mofetil substantially suppressed activity signatures from plasmablast, Th1, and central memory CD8 cells.

However, through stratified LD score regression using large-scale SLE-GWASs, we revealed that disease-activity signatures were less enriched around SLE risk variants than disease-state signatures. Consistent with this result, the directions of SLE risk alleles’ expression quantitative trait locus (eQTL) effects were significantly concordant with the directions of disease-state signatures, but not with those of activity signatures. These findings suggested that the current genetic case-control studies may not well capture clinically vital biology linked to drug target discovery for SLE. Meanwhile, we also detected some examples of activity signatures that might contribute to the disease risk by modulating risk allele’s eQTL effects.

Figure 1.

Conclusion

We identified comprehensive gene signatures reflecting the establishment and exacerbation of SLE, which provide essential foundations for future genomic, genetic, and clinical studies.

References

[1]Ota, M. et al. Dynamic landscape of immune cell-specific gene regulation in immune-mediated diseases. Cell 2021;184:3006-21.e17.

Acknowledgements

This study was supported by Chugai Pharmaceutical Co., Ltd., Tokyo, Japan; the Ministry of Education, Culture, Sports; and the Japan Agency for Medical Research and Development (AMED) (JP21tm0424221 and JP21zf0127004).

Disclosure of Interests

Masahiro Nakano: None declared, Mineto Ota Grant/research support from: Mineto Ota belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yusuke Takeshima Grant/research support from: Yusuke Takeshima belonged to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Yukiko Iwasaki: None declared, Hiroaki Hatano: None declared, Yasuo Nagafuchi Grant/research support from: Yasuo Nagafuchi belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kwangwoo Kim: None declared, So-Young Bang: None declared, Hye Soon Lee: None declared, Hirofumi Shoda: None declared, Xuejun Zhang: None declared, Sang-Cheol Bae: None declared, Chikashi Terao: None declared, Kazuhiko Yamamoto: None declared, Tomohisa Okamura Grant/research support from: Tomohisa Okamura belongs to the Social Cooperation Program, Department of functional genomics and immunological diseases, supported by Chugai Pharmaceutical., Kazuyoshi Ishigaki: None declared, Keishi Fujio Speakers bureau: Keishi Fujio receives speaker fees from Chugai Pharmaceutical., Consultant of: Keishi Fujio receives consulting honoraria from Chugai Pharmaceutical., Grant/research support from: Keishi Fujio receives research support from Chugai Pharmaceutical.

47XXY and 47XXX in Scleroderma and Myositis

Objective

We undertook this study to examine the X chromosome complement in participants with systemic sclerosis (SSc) as well as idiopathic inflammatory myopathies.

Methods

The participants met classification criteria for the diseases. All participants underwent single‐nucleotide polymorphism typing. We examined X and Y single‐nucleotide polymorphism heterogeneity to determine the number of X chromosomes. For statistical comparisons, we used χ² analyses with calculation of 95% confidence intervals.

Results

Three of seventy men with SSc had 47,XXY (P = 0.0001 compared with control men). Among the 435 women with SSc, none had 47,XXX. Among 709 men with polymyositis or dermatomyositis (PM/DM), seven had 47,XXY (P = 0.0016), whereas among the 1783 women with PM/DM, two had 47,XXX. Of 147 men with inclusion body myositis (IBM), six had 47,XXY, and 1 of the 114 women with IBM had 47,XXX. For each of these myositis disease groups, the excess 47,XXY and/or 47,XXX was significantly higher compared with in controls as well as the known birth rate of Klinefelter syndrome or 47,XXX.

Conclusion

Klinefelter syndrome (47,XXY) is associated with SSc and idiopathic inflammatory myopathies, similar to other autoimmune diseases with type 1 interferon pathogenesis, namely, systemic lupus erythematosus and Sjögren syndrome.

POS0345 CLINICOGENETIC STUDY OF FIVE NOVEL SUSCEPTIBILITY LOCI FOR TAKAYASU ARTERITIS: SUSCEPTIBILITY LOCI IN THE IL12B AND PTK2B REGION, BUT NOT THE LILRA3, DUSP22, KLHL33 REGIONS, ARE ASSOCIATED WITH VASCULAR DAMAGE IN TAKAYASU ARTERITIS

Background:

We have previously identified single nucleotide polymorphism (SNP) rs6871626 in IL12B, rs103294 in LILRA3, rs17133698 in DUSP22, rs2322599 in PTK2B, and rs1713450 in KLHL33 as non-HLA susceptibility loci in Takayasu arteritis (TAK) [1, 2]. However, the association of these SNPs with clinical features has scarcely investigated.

Objectives:

In this study, we aimed to examine how these SNPs contribute to clinical features and vascular damage in TAK.

Methods:

We enrolled 99 TAK patients who were enrolled in our previous genome-wide association study (GWAS) [2]. To assess vascular damage, Takayasu Arteritis Damage Score (TADS) and Vasculitis Damage Index (VDI) were measured at the last visit before November 2020. As for organ damages, the presence or absence of aortic regurgitation (AR), hypertension, ischemic heart disease, cerebrovascular event, visual loss, end-stage renal failure, and inflammatory bowel disease were evaluated. Treatment profiles including immunosuppressive drugs and vascular interventions were also reviewed.

Results:

The incidence of AR was positively associated with the risk allele of IL12B rs6871626 (p=0.0052; odds ratio (OR) 2.45, 95% confidence interval (CI) 1.27-4.73), and so was the proportion of patients who underwent aortic valve replacement (p=0.023; OR 3.64, 95% CI 1.08-12.24) (table 1). The incidence of hypertension was associated with the risk allele of IL12B rs6871626 (p=0.049; OR 1.82, 95% CI 0.99-3.36) and PTK2B rs2322599 (p=0.044; OR 2.52, 95% CI 0.97-6.54) (table 1). The proportion of biologic users tended to be higher in the risk genotypes of IL12B rs6871626 (p=0.15; OR1.80, 95% CI 0.79-3.99). Regarding vascular damage, there was positive correlation between TADS and the risk allele of IL12B rs6871626 (p=0.0035; β= 1.35) (Figure 1). Moreover, VDI was also positively correlated with the allele (p=0.0054; β= 0.96) (Figure 1). No other clinicogenetic associations were observed between five SNPs and vasculitis-associated damages.

Table 1.

The association of the five SNPs with aortic regurgitation and hypertension

Aortic regurgitationHypertensionOR (95% CI)p valueOR (95% CI)p valueIL12B rs68716262.45 (1.27-4.73)0.0052*1.82 (0.99-3.36)0.049*PTK2B rs23225991.21 (0.51-2.86)0.672.51 (0.97-6.54)0.044*LILRA3 rs1032941.16 (0.52-2.61)0.711.20 (0.55-1.64)0.64DUSP22 rs171336980.56 (0.28-1.13)0.0900.87 (0.46-1.63)0.66KLHL33 rs17134500.89 (0.42-1.91)0.771.48 (0.68-3.22)0.31

SNP, single nucleotide polymorphism; OR, odds ratio; CI, confidence interval

Conclusion:

In the present study, IL12B rs6871626 was closely correlated with vascular damage. We also found association between PTK2B rs2322599 and hypertension. There was no significant relevance between vascular damage and LILRA3 rs103294, DUSP22 rs17133698, or KLHL33 rs1713450.

References:

[1]Terao C et al. Am J Hum Genet. 2013;93(2):289-97.

[2]Terao C et al. Proc Natl Acad Sci U S A. 2018;115(51):13045-50.

Disclosure of Interests:

Keiichiro Kadoba: None declared, Ryu Watanabe Speakers bureau: I have received speaker’s fee from Mitsubishi Tanabe Pharma, Pfizer, Sanofi, AbbVie, Asahi Kasei, Eisai, Eli Lilly, Bristol-Myers Squibb, and Janssen., Takeshi Iwasaki: None declared, Koji Kitagori Grant/research support from: KK has received research grants from GlaxoSmithKline., Syuji Akizuki: None declared, Kosaku Murakami Speakers bureau: I have received speaking fees from Eisai Co. Ltd, Chugai Pharmaceutical Co. Ltd., Pfizer Inc., Bristol-Myers Squibb, Mitsubishi Tanabe Pharma Corporation, UCB Japan Co. Ltd, Daiichi Sankyo Co. Ltd. and Astellas Pharma Inc., Ran Nakashima: None declared, Motomu Hashimoto Speakers bureau: I have received a research grant and/or speaker fee from Bristol-Myers, Eisai, Ely Lilly, Mitsubishi Tanabe Pharma., Grant/research support from: I have received a research grant and/or speaker fee from Bristol-Myers, Eisai, Ely Lilly, Mitsubishi Tanabe Pharma., Masao Tanaka Speakers bureau: I have received research grants and/or speaker fees from AbbVie GK, Asahi Kasei Pharma Corporation, Astellas Pharma Inc., Bristol-Myers Squibb, Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly and Company, Pfizer Inc., UCB Japan Co., Ltd., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Corporation, Novartis Pharma K.K., Taisho Pharma Co., Ltd, and Takeda Pharmaceutical Company Limited., Koichiro Ohmura Speakers bureau: I have received speaker’s fee from Abbvie, Actelion, Asahikasei Pharma, Astellas, AYUMI, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, GSK, Janssen, JB, Mitsubishi Tanabe, Nippon Kayaku, Nippon Shinyaku, Novartis, Sanofi and Takeda., Grant/research support from: I have received research grants from GlaxoSmithKline., Akio Morinobu Speakers bureau: I have received speaking fees from Chugai Pharmaceutical Co. Ltd., Grant/research support from: I have received research grants from Chugai Pharmaceutical Co. Ltd., Chikashi Terao: None declared, Hajime Yoshifuji Speakers bureau: I have received lecture fees from Chugai., Consultant of: I have been an advisory board for a clinical trial conducted by Janssen.

SAT0585 GEO-EPIDEMIOLOGY OF AUTOANTIBODIES IN RA: DIFFERENT PREVALENCES IN FOUR ETHNICALLY DIVERSE RA POPULATIONS

Background:

Rheumatoid arthritis (RA) has been described in virtually every ethnic population. Most RA patients harbor anti-modified protein antibodies (AMPAs), including anti-citrullinated protein (ACPA), anti-carbamylated protein (anti-CarP), anti-malondialdehyde acetaldehyde (anti-MAA), and anti-acetylated protein antibodies (AAPA). However, it is unclear whether differences exist in the AMPA response between different ethnic groups. Such differences could provide new clues to genetic and environmental factors contributing to autoantibody development.

Objectives:

To investigate the prevalence of different AMPA in four ethnically diverse RA populations, and their association with smoking.

Methods:

Enzyme-linked immunosorbent assays were used to measure anti-CarP IgG, anti-MAA IgG (both in-house), and anti-acetylated vimentin IgG (Orgentec) in ACPA-positive sera of Dutch (NL, n=103), Japanese (JP, n=174), Canadian First Nations People (FN, n=100), and black South Africans (SA, n=67) fulfilling the 1987 ACR classification criteria for RA. Ethnicity-matched local healthy controls were used to calculate cohort-specific cut-offs. Logistic regression was used to identify whether ever-smoking was associated with AMPA seropositivity in each cohort, corrected for age, gender, and disease duration. Random-effects meta-analysis was used to pool the resulting odds ratios (OR).

Results:

For all three AMPAs, median levels were higher in FN and especially SA than NL and JP patients (Figure 1). The median autoantibody levels in arbitrary units (in % of patients positive) for NL, JP, FN and SA RA patients were: anti-CarP IgG: 1157 (47%), 994 (43%), 1642 (58%) and 2336 (76%) (p<0.001); anti-MAA IgG: 131 (29%), 179 (22%), 251 (29%) and 257 (53%) (p<0.001); AAPA: 133 (20%), 136 (17%), 153 (38%) and 316 (28%) (p<0.001). Prevalence, meaning positivity, also differed significantly between cohorts for all AMPAs (p<0.001).There were also marked differences in total IgG levels in mean (SD) g/L: 13 (4) for NL, 17 (6) for JP, 18 (6) for FN, and 25 (8) for SA (p<0.001). When the autoantibody levels were normalized to total IgG, the differences in became less pronounced between cohorts (Figure 2). The median arbitrary units per g/L Total IgG for NL, JP, FN and SA RA patients were: anti-CarP IgG: 54, 25, 53, and 79; anti-MAA IgG: 6, 5, 8, and 9; and AAPA: 2, 2, 2, and 3, suggesting that autoantibody level differences may partly correspond to cohort-specific differences in total IgG, although the overall trend of higher levels in SA persisted. There was no association between smoking and anti-CarP or anti-MAA positivity, with pooled OR (95% CI) of 1.31 (0.79-2.18) and 0.85 (0.46-1.56), respectively. However, smoking was positively and consistently associated with AAPA positivity in each cohort: pooled OR (95% CI) of 2.01 (1.06-3.81).

Conclusion:

In these ACPA-positive ethnically diverse RA populations, levels and prevalence of various AMPAs differ, suggesting that ethnic background and environment may influence the development of the autoantibody response in RA. Despite these differences, our results imply smoking as a consistent risk factor for AAPA across different ethnic backgrounds.

Disclosure of Interests:

Emma C. de Moel: None declared, Veerle Derksen: None declared, Leendert A Trouw: None declared, Chikashi Terao: None declared, Mohammed Tikly: None declared, Hani El-Gabalawy: None declared, Holger Bang Grant/research support from: Employee of Orgentec Diagnostika, Thomas Huizinga Grant/research support from: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Consultant of: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Rene Toes: None declared, Diane van der Woude: None declared

THU0023 DETAILED PROFILE OF CO-OCCURRENCE OF RELAPSING POLYCHONDRITIS AND AUTOIMMUNE THYROID DISEASE

Background:

Relapsing polychondritis (RP) is a rare inflammatory disease, which is characterized by recurrent inflammation and destruction of cartilage tissues. RP also has the profile of autoimmune disease and is often complicated with other autoimmune disease. Autoimmune thyroid disease (AITD) is one of common autoimmune diseases, which consists of Graves’ disease (GD) and Hashimoto’s thyroiditis (HT). While RP is reported to be complicated with AITD1), there has been no study on detailed profile of co-occurrence of RP and AITD.

Objectives:

We aimed to reveal whether there is common (statistically significant) co-occurrence of RP and AITD. We also analyzed clinical and genetic profiles characterizing the co-occurrence.

Methods:

We recruited 117 patients with RP and checked their medical records in order to obtain the information about compilation of AITD and clinical features. In addition, we genotyped Human Leucocyte Antigen (HLA) A, B Cw, DRB1, DQB1 and DPB1 alleles for 88 of the 117 patients. Co-occurrence ratio was compared with prevalence of AITD in the Japanese population. Associations of co-occurrence of AITD with clinical manifestations or HLA alleles were analyzed among the patients.

Results:

Among the 117 patients with RP, 5 (4.3%) and 6 (5.1%) patients had GD and HT, respectively. Patients with RP were more likely to be complicated with GD (p=1.04×10-3, OR: 7.15, 95%CI 2.68~ 18.14) but not with HT (p=0.50, 95%CI 0.59~1.27), compared with prevalence in general Japanese population (0.62% and 5.9%, respectively2)). RP patients with GD showed a trend to have nasal involvement (100% vs 45.5%, p=0.023, OR: 2.58, 95%CI 1.09~∞). We did not observe any differences in clinical manifestation in patients with RP and HT. HLA- DPB1*02:02 demonstrated a trend toward GD complication (20% vs 2.3%, p=0.035, OR: 10.41, 95%CI 1.23~65.38). There were no association of HLA in the complication of HT among patients with RP.

Conclusion:

Patients with RP have high co-occurrence ratio of GD. Patients with the two diseases may be characterized by nasal involvement and HLA-DPB1*02:02.

References:

[1]Kung AW et al. Graves’ ophthalmopathy and relapsing polychondritis. Clin Exp Rheumatol. 1995 Jul-Aug;13(4):501-3.

[2]Nagataki S et al. Thyroid diseases among atomic bomb survivors in Nagasaki. JAMA. 1994 Aug 3;272(5):364-70.

Disclosure of Interests:

Toshiki Nakajima Speakers bureau: Bristol-Myers Squibb and Novartis, Hajime Yoshifuji Grant/research support from: Astellas Pharma. (Outside the field of the present study.), Speakers bureau: Chugai Pharmaceutical. (Outside the field of the present study.), Yoshihisa Yamano: None declared, Hiroshi Handa: None declared, Koichiro Ohmura Grant/research support from: Astellas Pharma, AYUMI Pharmaceutical, Chugai Pharmaceutical, Daiichi Sankyo, Eisai, Japan Blood Products Organization, Mitsubishi Tanabe Pharma, Nippon Kayaku, Nippon Shinyaku, Sanofi, and Takeda Pharmaceutical., Speakers bureau: AbbVie, Actelion Pharmaceuticals Japan, Asahi Kasei Pharma, AYUMI Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Eli Lilly and Company, GlaxoSmithKline, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Novartis Pharma, and Sanofi., Tsuneyo Mimori: None declared, Chikashi Terao Grant/research support from: Actelion, Speakers bureau: Asteras, Asahi Kasei Pharma, Ono and Tanabe-Mitsubishi

Interleukin-18 is associated with the presence of interstitial lung disease in rheumatoid arthritis: a cross-sectional study

OBJECTIVE

Serum interleukin-18 (IL-18) levels are increased in patients with interstitial lung disease (ILD). In addition, IL-18 levels are increased in patients with rheumatoid arthritis (RA) and are associated with arthritis activity. We determined whether increased IL-18 levels are associated with ILD in RA.

METHOD

RA patients were enrolled using an RA cohort database. Plasma IL-18 levels were measured by enzyme-linked immunosorbent assay. ILD was determined by a pulmonologist and a radiologist based on chest radiography and computed tomography findings. IL-18 levels for RA with ILD and RA without ILD were compared. Associations between ILD and various markers including IL-18 and confounding factors (e.g. smoking history) were investigated by logistic regression analysis. Diagnostic values of IL-18 for the presence of ILD were investigated using receiver operating characteristics curve analysis.

RESULTS

ILD was complicated in 8.2% (n = 26) of the study population (N = 312). Plasma IL-18 levels were higher for RA patients with ILD than for RA patients without ILD (721.0 ± 481.4 vs 436.8 ± 438.9 pg/mL, p < 0.001). IL-18, Krebs von den Lungen-6, and anti-cyclic citrullinated peptide antibody titre and glucocorticoid doses were independently associated with the presence of ILD during multivariate logistic regression analysis. Sensitivity and specificity of IL-18 levels for the detection of ILD in RA patients were 65.3% and 76.3%, respectively (area under the curve = 0.73).

CONCLUSION

Plasma IL-18 levels were higher for RA patients with ILD than for those without ILD. Increased IL-18 levels were associated with the presence of ILD.

Periarticular osteoporosis of the forearm correlated with joint destruction and functional impairment in patients with rheumatoid arthritis

The relationship between periarticular osteoporosis in the distal forearm and joint destruction or functional impairment in patients with rheumatoid arthritis (RA) is not sufficiently elucidated. From a single institutional cohort study, we found a strong correlation between periarticular forearm bone mineral density (BMD) and joint destruction or functional impairment.

INTRODUCTION

This study was conducted to investigate (1) the difference between various periarticular regions of interest (ROIs) of BMD of the forearm, (2) the correlation between periarticular forearm BMD and joint destruction and physical function, (3) the independent variables for predicting BMD of the forearm, and (4) the forearm BMD of different ROIs in the early stage of RA.

METHODS

We conducted a cross-sectional study in an RA cohort. Measurements included BMD of the distal forearm, joint destruction of the hands assessed by modified total Sharp score (mTSS), functional impairment assessed by a health assessment questionnaire (HAQ), and other clinical data. Variables affecting the forearm BMD values were analyzed by correlation and stepwise regression analyses.

RESULTS

Of the 405 patients enrolled in the present study, 370 (average age; 62.9 years) were identified as having definite RA with a complete set of data. BMD in the distal end of the forearm (BMDud) was significantly reduced compared with that in the distal third of the forearm (BMD1/3). In a stepwise regression analysis, the mTSS in BMD1/3 was an independent predicting variable, while age and partial HAQ scores associated with the upper extremity were common independent variables in BMDud and BMD1/3. BMDud was significantly less than BMD1/3, even in patients with a short duration of the disease. BMD1/3 was significantly less in non-remission group compared with that in remission group in patients with a short duration of the disease.

CONCLUSION

Periarticular BMD in the distal forearm is closely correlated with joint destruction and functional impairment in RA. Periarticular BMD in the distal forearm may be already reduced at the clinical manifestation of the disease.

A nationwide study of SLE in Japanese identified subgroups of patients with clear signs patterns and associations between signs and age or sex

We performed a nationwide study to determine the distributions of the signs and clinical markers of systemic lupus erythematosus (SLE) and identify any patterns in their distributions to allow patient subclassification. We obtained 256,999 patient-year records describing the disease status of SLE patients from 2003 to 2010. Of these, 14,779 involved patients diagnosed within the last year, and 242,220 involved patients being followed up. Along with basic descriptive statistics, we analyzed the effects of sex, age and disease duration on the frequencies of signs in the first year and follow-up years. The patients and major signs were clustered using the Ward method. The female patients were younger at onset. Renal involvement and discoid eczema were more frequent in males, whereas arthritis, photosensitivity and cytopenia were less. Autoantibody production and malar rash were positively associated with young age, and serositis and arthritis were negatively associated. Photosensitivity was positively associated with a long disease duration, and autoantibody production, serositis and cytopenia were negatively associated. The SLE patients were clustered into subgroups, as were the major signs. We identified differences in SLE clinical features according to sex, age and disease duration. Subgroups of SLE patients and the major signs of SLE exist.

Discordance and accordance between patient's and physician's assessments in rheumatoid arthritis

OBJECTIVES

The American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria for rheumatoid arthritis (RA) are more stringent than index-based criteria, making it more difficult to achieve a patient's global assessment (PGA) than an evaluator's global assessment (EGA). We investigated the reason for the discrepancy between the PGA and the EGA in a Japanese clinical cohort.

METHOD

We assessed clinical and laboratory variables in our clinical cohort. The frequency of remission achievement according to the ACR/EULAR remission criteria and predictors of the discrepancy between the PGA and EGA were analysed.

RESULTS

Of 370 patients with RA, 89 fulfilled PGA criteria and 167 patients fulfilled EGA criteria. The PGA was highly correlated with the visual analogue scale (VAS) pain score and non-inflammatory variables including Steinbrocker class and the Health Assessment Questionnaire Disability Index (HAQ-DI). Conversely, inflammatory variables, including swollen joint count (SJC), tender joint count (TJC), and C-reactive protein (CRP) levels, were significantly associated with the EGA. The main predictors of the discrepancy between the PGA and the EGA were patient's VAS pain score, SJC, and functional disability.

CONCLUSIONS

Increased pain and functional disability led to a discrepancy towards a worse PGA than EGA, whereas increased SJC led to an accordance towards a worse EGA.

Interferon-gamma release assay for diagnosing Mycobacterium tuberculosis infections in patients with systemic lupus erythematosus

Our aim was to analyze the performance of an interferon-gamma release assay, QuantiFERON-TB Gold (QFT-2G), for diagnosing Mycobacterium tuberculosis (MTB) infection in patients with systemic lupus erythematosus (SLE). We performed the QFT-2G and tuberculin skin test (TST) in 71 SLE patients. The QFT-2G results of 279 patients with other connective tissue diseases (CTD) and 35 healthy controls were analyzed. Of the 71 SLE patients, two (2.8%) were positive and 46 (64.8%) were negative by QFT-2G. All SLE patients had no evidence of active MTB infection, apart from one. QFT-2G produced a significantly higher number of indeterminate results in patients with SLE (23/71, 32.4%) compared with those with other CTD (5.7%) or healthy controls (0%) ( p < 0.0001 and p < 0.0001). Decreased lymphocyte counts and high SLEDAI scores in SLE patients were shown to be risk factors for indeterminate results by multivariate analysis ( p = 0.02 and p = 0.04). Among all patients with CTD, SLE itself and lymphocytopenia were found to be independent risks for indeterminate results ( p = 0.00000625 and p = 0.000107). In conclusion, QFT-2G may have more potential to assist in the diagnosis of active and latent MTB infection than TST in SLE patients. However, because of the high frequency of indeterminate results, caution must be used when interpreting the results of QFT-2G among SLE patients, especially those who have parallel or subsequent flares.

Medical consultation rate of allergic rhinitis and pollinosis surveillance in Aichi, Japan

The medical consultation rate of allergic rhinitis (AR) was analysed using Japan National Health Insurance records of Aichi Prefecture for May 1989. Data collected from 88 cities, towns and villages were tabulated and divided into five-year age groups. The standardized medical consultation rate (SMCR) of AR in each municipality was then calculated. It was found that SMCR of AR did not correlate well with the pollen count for Japanese cedars, Japanese cypresses or gramineae, respectively, but a weak correlation with the mean yearly levels of nitrogen dioxide was suggested by the data. There was a significant positive correlation between SMCR of AR and the mean yearly levels of suspended particulate matter, the major element of which is diesel exhaust particulate.

Alcohol consumption and cancers of hormone-related organs in females

The relations between alcohol consumption and cancers of the breast, corpus uteri and ovary were investigated in a case-control study involving 1,740 cases of breast cancer, 239 cases of cancer of the corpus uteri, 417 cases of ovarian cancer and 8,920 controls with other cancer sites identified from the Aichi Cancer Registry, Japan 1980-1986. The age-adjusted relative risk (RR) of daily alcohol drinkers compared to non-drinkers was significantly increased for breast cancer (RR = 1.36, 95% confidence interval (CI) 1.04-1.78), that for cancer of the corpus uteri was lowered insignificantly (RR = 0.44, 95% CI 0.15-1.38) and that for ovarian cancer was significantly lowered (RR = 0.38, 95% CI 0.16-0.90). The increase in the risk of breast cancer associated with daily alcohol drinking was evident in the age range 50 and over, the risk specified by type of alcoholic beverage being highest for beer. Multivariate analyses controlled for age, residence, marital status, occupation, smoking habit and family history of breast cancer did not materially change the RRs of daily alcohol drinkers. Despite the several limitations of the study, the results were consistent with those of previous studies from other countries, suggesting that alcohol consumption may contribute to the risk of breast cancer in Japanese woman, as it dose elsewhere. The present study also suggested alcohol consumption not to be associated with elevated risks of cancer in other hormone-related organs in females, and possibly to be associated with a decreased risk of ovarian cancer.

An epidemiological study on marital status and cancer incidence

The relationship between marital status and cancer incidence was examined based on 49,191 incident cases aged 30 or over in 1980-1984 by using the data from Aichi Cancer Registry and census data. Although married and widowed people did not show increased incidence for any cancer site studied, single and divorced people showed statistically significantly increased or decreased risks for several sites of cancer. Single males showed an increased risk for esophageal cancer and a decreased risk for lung cancer. Divorced males showed increased risks for cancers of the mouth & pharynx, esophagus, liver, skin and brain. Single females showed increased risks for cancers of the esophagus, stomach, small intestine, liver, pancreas, lung, breast, corpus uteri, ovary & fallopian tube and other female genital organs and a decreased risk for cervical cancer. Divorced females showed increased risks for cancers of the larynx, breast, all parts of uterus and cervix uteri and a decreased risk for biliary tract cancer. The increased risk for breast cancer in single females was more pronounced in older age groups and the increased risks for several sites of cancer in divorced people were more pronounced in younger age groups. These findings may be partly explained by differences in reproductive factors and life style, especially smoking and drinking habits.

Pseudothrombocytopenia with cold-type platelet agglutinins

Pseudothrombocytopenia is an in vitro phenomenon of platelet agglutination and clumping in the presence of EDTA on the electronical measurement of platelet count. Agglutinins reacting with platelet antigens belong to one heavy and one light chain of immunoglobulins with or without complement by immunofluorescence. The platelets are markedly agglutinated in EDTA, but scarcely in the presence of other anticoagulants. Agglutinations seem to occur more readily at cold temperature rather than at 37 degrees C.