Identification of six novel susceptibility loci for dyslipidemia by longitudinal exome-wide association studies in Japanese

Background

The circulating concentrations of triglycerides, high density lipoprotein (HDL)-cholesterol, and low density lipoprotein (LDL)-cholesterol have a substantial genetic component. Although previous genome-wide association studies identified various genes and loci related to plasma lipid levels, those studies were conducted in a cross-sectional manner.

Purpose

The purpose of the study was to identify genetic variants that confer susceptibility to hypertriglyceridemia, hypo-HDL-cholesterolemia, and hyper-LDL-cholesterolemia in Japanese. We have now performed longitudinal exome-wide association studies (EWASs) to identify novel loci for dyslipidemia by examining temporal changes in serum lipid profiles.

Methods

Longitudinal EWASs (mean follow-up period, 5 years) for hypertriglyceridemia (2056 case, 3966 controls), hypo-HDL-cholesterolemia (698 cases, 5324 controls), and hyper-LDL-cholesterolemia (2769 cases, 3251 controls) were performed with Illumina Human Exome arrays. The relation of genotypes of 24,691 single nucleotide polymorphisms (SNPs) that passed quality control to dyslipidemia-related traits was examined with the generalized estimating equation (GEE). To compensate for multiple comparisons of genotypes with each of the three conditions, we applied Bonferroni's correction for statistical significance of association. Replication studies with cross-sectional data were performed for hypertriglyceridemia (2685 cases, 4703 controls), hypo-HDL-cholesterolemia (1947 cases, 6146 controls), and hyper-LDL-cholesterolemia (1719 cases, 5833 controls).

Results

Longitudinal EWASs revealed that 30 SNPs were significantly (P<2.03 × 10–6 by GEE) associated with hypertriglyceridemia, 46 SNPs with hypo-HDL-cholesterolemia, and 25 SNPs with hyper-LDL-cholesterolemia. After examination of the relation of identified SNPs to serum lipid profiles, linkage disequilibrium, and results of the previous genome-wide association studies, we newly identified rs74416240 of TCHP, rs925368 of GIT2, rs7969300 of ATXN2, and rs12231744 of NAA25 as a susceptibility loci for hypo-HDL-cholesterolemia; and rs34902660 of SLC17A3 and rs1042127 of CDSN for hyper-LDL-cholesterolemia. These SNPs were not in linkage disequilibrium with those previously reported to be associated with dyslipidemia, indicating independent effects of the SNPs identified in the present study on serum concentrations of HDL-cholesterol or LDL-cholesterol in Japanese. According to allele frequency data from the 1000 Genomes project database, five of the six identified SNPs were monomorphic or rare variants in European populations. In the replication study, all six SNPs were associated with dyslipidemia-related phenotypes.

Conclusion

We have thus identified six novel loci that confer susceptibility to hypo-HDL-cholesterolemia or hyper-LDL-cholesterolemia. Determination of genotypes for these SNPs at these loci may prove informative for assessment of the genetic risk for dyslipidemia in Japanese.

Funding Acknowledgement

Type of funding source: None

Uretero-arterial fistula treated with endovascular stent graft following multiple interventions

INTRODUCTION

Uretero-arterial fistula is a rare life-threatening condition. Its diagnosis and management remains a challenge for urologists.

CASE PRESENTATION

A 64-year-old man presented to our hospital with gross hematuria. He had history of rectal cancer treated with neoadjuvant chemoradiotherapy followed by low anterior resection and chronic ureteral stenting for bilateral ureteral strictures. He developed recurrent hemorrhagic shocks due to sudden massive gross hematuria. Repeated computed tomography and angiography could not identify the source of bleeding. After prophylactic embolization of the right renal artery and right nephrectomy, angiography finally revealed a uretero-arterial fistula from the right external iliac artery. Percutaneous balloon-expandable covered stent graft was used to successfully treat the fistula.

CONCLUSIONS

Urologists should consider possible uretero-arterial fistula in patients with recurrent hematuria along with several risk factors and convincing medical history.

Identification of two genes as novel susceptibility loci for type 2 diabetes mellitus in Japanese

Background

The heritability of Type 2 diabetes mellitus (T2DM) has been estimated to be 50% to 60%. Although genome-wide association studies identified >120 loci that confer susceptibility to T2DM, these studies were commonly conducted in a cross-sectional manner.

Purpose

The purpose of the study was to identify genetic variants that confer susceptibility to T2DM in Japanese. We have now performed longitudinal exome-wide association studies (EWASs) to identify novel loci for T2DM by examining temporal changes in fasting plasma glucose (FPG) level, blood hemoglobin A1c (HbA1c) content, and the prevalence of T2DM.

Methods

Longitudinal EWASs (mean follow-up period, 5 years) were performed with Illumina Human Exome-12 v1.2 DNA Analysis BeadChip or Infinium Exome-24 v1.0 BeadChip arrays and with 6,022 Japanese (755 subjects with T2DM, 5267 controls). The relation of genotypes of 24,579 SNPs that passed quality control to FPG level, blood HbA1c content, or the prevalence of T2DM was examined with the generalized estimating equation (GEE). To compensate for multiple comparisons of genotypes with each of the three parameters, we applied Bonferroni's correction for statistical significance of association.

Results

Longitudinal EWASs (GEE with adjustment for age, sex, body mass index, and smoking) revealed that rs6414624 of EVC (P<2.0×10–16 for T2DM, P=9.1×10–11 for FPG), rs78338345 of GGA3 (P<2.0×10–16 for T2DM, P=4.3×10–9 for FPG), rs10490775 of PTPRG (P<2.0×10–16 for T2DM, P=3.3×10–7 for FPG), and rs61739510 of GLT6D1 (P<2.0×10–16 for T2DM, P=5.8×10–7 for FPG) were significantly associated with the prevalence of T2DM and FPG levels; and rs11558471 in SLC30A8 with FPG level (P=1.8×10–8) and blood HbA1c content (P=1.2×10–7). After examination of the relation of identified SNPs to FPG level and blood HbA1c content, linkage disequilibrium of the SNPs, and results of the previous genome-wide association studies, we identified rs6414624 of EVC and rs78338345 of GGA3 as novel susceptibility loci for T2DM. In the identified SNPs (rs6414624 and rs7833834), FPG level, blood HbA1c content, and the prevalence of T2DM were significantly lower in homozygotes with the minor alleles than in homozygotes with the major alleles or heterozygotes. These results suggest that the minor alleles of rs6414624 and rs78338345 are protective against T2DM in Japanese. According to allele frequency data from the 1000 Genomes Project database, the minor G allele of rs78338345 of GGA3 is specifically distributed in East Asia. This suggests that the minor allele frequency may have increased in East Asian populations after the split of East Asian and non-East Asian populations.

Conclusion

We have newly identified EVC and GGA3 as susceptibility loci for T2DM in Japanese. Determination of genotypes for these SNPs at these loci may prove informative for assessment of the genetic risk for T2DM in Japanese.

Funding Acknowledgement

Type of funding source: None

Effect of therapeutic plasma exchange on phenytoin plasma concentration in patients receiving intravenous fosphenytoin therapy

We report for patients with encephalitis treated with plasma exchange (PE) and fosphenytoin. In patient 1, phenytoin levels decreased on the maintenance dose, and the phenytoin concentration was <10 μg/mL on day 12 of administration. In patient 2, the phenytoin levels was <10 μg/mL on day 4. Increasing the fosphenytoin dose pushed the phenytoin level into therapeutic range. There were no differences between the areas under the concentration-time curve of phenytoin with and without PE. We previously reported a decline in phenytoin levels after prolonged use of fosphenytoin. Therefore, dose adjustment of fosphenytoin in patients undergoing PE may be unnecessary.

Susceptibility of patients receiving chemotherapy for haematological malignancies to scabies

BACKGROUND

Scabies is a contagious dermatosis. The risk factors for its transmission remain unclear. A scabies outbreak, involving patients who were receiving chemotherapy for haematological malignancies, occurred at our hospital.

METHODS

The outbreak population was analysed to determine whether the incidence of scabies was higher among contact patients receiving chemotherapy for haematological malignancies.

RESULTS

A patient with crusted scabies was the index case, and 18 of 78 contact healthcare workers (HCWs) and 22 of 135 contact patients were diagnosed with classical scabies. Ten of 17 contact patients with haematological malignancies and 12 of 118 contact patients with other diseases were infected with scabies. The incidence rate was significantly higher among the patients with haematological malignancies (P<0.001). The patients with haematological malignancies had a significantly lower mean minimum neutrophil count than those with other diseases (1159/μL vs 3761/μL, P=0.0012). Most haematological patients did not require special nursing assistance, suggesting that the higher incidence of scabies among these patients resulted from their immunodeficiency rather than greater skin-to-skin contact with infected HCWs.

CONCLUSION

Our study suggests that patients receiving chemotherapy for haematological malignancies are more susceptible to scabies than patients with other diseases, and require stricter protection.

AB0266 ANALYSIS OF STRESS AND FATIGUE IN PATIENTS WITH RHEUMATOID ARTHRITIS USING A DIGITIZING DEVICE

Background:

Stress and fatigue are evaluated subjectively by patients using a visual analog scale (VAS) and questionnaires such as the SF-36 and the FACIT Fatigue Scale. Such evaluations are based on patients’ self-reported outcomes. It is difficult to evaluate stress and fatigue objectively. A digitizing device was used to quantify stress objectively.

Objectives:

To evaluate the correlations of a digitizing device and a VAS or a questionnaire about stress and fatigue, and the relationships with disease activity of patients with rheumatoid arthritis (RA).

Methods:

Data from a prospective observational study (CHIKARA study: Correlation researcH of sarcopenIa, sKeletal muscle and disease Activity in Rheumatoid Arthritis) were used. The study protocol was reported previously1. A total of 84 RA patients entered the study and were evaluated using a stress digitizing device (Smart Pulse, MEDICORE Co. LTD). This device evaluates stress based on heart rate variability theory2. The objective physical stress score (O-physical ST), mental stress score (O-mental ST), and total stress score (O-total ST) were calculated, ranging from 0 to 100 (higher score indicating greater stress). A questionnaire for stress, the Perceived Stress Scale3(PSS) 10 Japanese version (minimum 0, maximum 40), and VAS evaluations of stress (stress-VAS) and fatigue (fatigue-VAS) were carried out. The correlations between subjective and objective methods were analyzed. The relationships between stress, fatigue, and disease activity of RA patients were examined.

Results:

The patients’ mean age was 68.6 years (women n=66, men n=18), disease duration was 8.8 years, DAS28ESR was 3.24, and modified Health Assessment Questionnaire (mHAQ) was 0.5. The average PSS10 was 26.1, which was higher than in healthy individuals (20.3). The fatigue-VAS was higher than the stress-VAS (41.3 vs 34.5 mm). The O-physical ST score was similar to the O-mental ST score (39.5 vs 37.4). Correlations are shown in Table. The O-physical ST was positively correlated with the fatigue-VAS (R=0.243 p=0.026), and the O-mental ST was also positively correlated with the stress-VAS (R=0.267 p=0.014). However, there was no correlation between the PSS10 and objective stress parameters. The DAS28-ESR was correlated with the fatigue-VAS (R=0.223 p=0.041) and the O-total ST (R=0.329 p=0.002). The stress scale (O-total ST) was worse with moderate and high disease activity than in remission (Figure).

Conclusion:

The stress score obtained by an objective digitizing device was correlated with stress- and fatigue-VAS scores. However, there was no correlation with the PSS10 questionnaire. It was found that the fatigue-VAS score and the objective total stress score were high with worse disease control.

References:

[1]Tada, M., Yamada, Y., Mandai, K. & Hidaka, N. Matrix metalloprotease 3 is associated with sarcopenia in rheumatoid arthritis - results from the CHIKARA study.Int J Rheum Dis21, 1962-1969, doi:10.1111/1756-185X.13335 (2018).

[2]Heart rate variability: standards of measurement, physiological interpretation and clinical use. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology.Circulation93, 1043-1065 (1996).

[3]Cohen, S., Kamarck, T. & Mermelstein, R. A global measure of perceived stress.J Health Soc Behav24, 385-396 (1983).

Table.

Correlation coefficients of subjective and objective evaluations of stress and fatigue in patients with RA

PSS10Stress-VASfatigue-VASO-physical STO-mental STO-total STPSS100.580**0.404**0.0660.0550.004Stress-VAS0.673**0.0070.267*0.023Fatigue-VAS0.243*0.0590.160O-physical ST-0.224*0.708**O-mental ST-0.017O-total ST

*: p<0.05, **: p,0.01, Spearman rank correlation coefficient

Disclosure of Interests:

None declared

AB0215 EARLY IMPROVEMENT OF THE POWER DOPPLER SIGNAL CAN PREDICT TO CONTINUE THE BIOLOGICAL DMARDS AFTER 1 YEAR

Background:

In rheumatoid arthritis (RA), biologics treatment is one of the effective treatment options. On the other hand, the effects of biologics cannot be obtained satisfactorily in all patients, and there are some cases in which treatment is interrupted due to ineffective or adverse events. However, the useful predictive markers of the biologics have not been found in the early phase of treatment in RA. Recently, ultrasound (US) has played a role of sensitive imaging modality in the diagnosis and follow-up of patients with RA.

Objectives:

In this study, we investigated whether continuation of biologics treatment can be predicted by ultrasonographic findings in the early phase.

Methods:

Fifty-four RA patients who started the first biologics from September 2016 to December 2018 were included. All the patients were performed clinical examination, blood tests and US examination of hand and foot at baseline, 4, 12, 24, 36 and 52 weeks. US examination was performed on MCP joints, PIP joints, wrist and MTP joints.

Results:

Among 54 cases, 42 cases were able to continue treatment until one year later, and the continuation rate was 80.8%. Of the 12 patients who discontinued first biologics treatment, 5 were changes to other biologics due to inadequate response, 4 were their wishes, and 3 were adverse events. Multiple regression analysis was performed with treatment continuation as the dependent variable and improvement of CRP, MMP-3, DAS28-CRP, grayscale score and power Doppler score in 4 weeks as explanatory variables. Only improvement of power Doppler score was extracted as a significant predictor (p = 0.045). In the continuation group, the improvement of the power Doppler signal at week 4 was 36% compared with the baseline, compared with 10% in the discontinuation group.

Conclusion:

The early improvement of power Doppler signal in 4 weeks could be a predictive factor for the continuation of 1-year biological treatment.

References:

[1]Grassi W, Okano T, Di Geso L, Filippucci E. Imaging in rheumatoid arthritis: options, uses and optimization. Expert Rev Clin Immunol. 2015;11:1131-46.

[2]Atzeni F, Talotta R, Masala IF, Bongiovanni S, Boccassini L, Sarzi-Puttini P. Biomarkers in Rheumatoid Arthritis. Isr Med Assoc J. 2017;19:512-6.

Table 1.

Multivariate regression analysis of predictive factors for continuation of biologics treatment in 1-year.

Improvement ratio of 0 to 4 weeksbetaP valueCRP-0.1220.465MMP-30.2280.103DAS28 CRP0.2800.103Ultrasound grey scale score-0.3420.119Ultrasound power Doppler score0.4420.045

Acknowledgments:

We thank Emi Yamashita, Yuko Yoshida, Asami Fujii and Shingo Washida who performed ultrasound examination.

Disclosure of Interests:

Tadashi Okano Grant/research support from: AbbVie, Eisai, Mitsubishi Tanabe Pharma Corporation and Nipponkayaku, Speakers bureau: AbbVie, Asahikasei, Astellas Pharma Inc, Ayumi Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, Daiich Sankyo, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, Novartis Pharma, Ono Pharmaceutical, Pfizer, Sanofi, Takeda Pharmaceutical, Teijin Pharma and UCB, Kenji Mamoto: None declared, Yutaro Yamada: None declared, Koji Mandai: None declared, Shohei Anno: None declared, Kentaro Inui Grant/research support from: Janssen Pharmaceutical K.K., Astellas Pharma Inc., Sanofi K.K., Abbvie GK, Takeda Pharmaceutical Co. Ltd., QOL RD Co. Ltd., Mitsubishi Tanabe Pharma, Ono Pharmaceutical Co. Ltd., Eisai Co.,Ltd.,, Speakers bureau: Daiichi Sankyo Co. Ltd., Mitsubishi Tanabe Pharma, Janssen Pharmaceutical K.K., Astellas Pharma Inc., Takeda Pharmaceutical Co. Ltd., Ono Pharmaceutical Co. Ltd., Abbvie GK, Pfizer Inc., Eisai Co.,Ltd., Chugai Pharmaceutical Co., Ltd., Tatsuya Koike Grant/research support from: AbbVie, Astellas Pharma Inc, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, MSD, Ono Pharmaceutical, Pfizer, Roche, Takeda Pharmaceutical, Teijin Pharma, and UCB, Speakers bureau: AbbVie, Astellas Pharma Inc, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Janssen, Lilly, Mitsubishi Tanabe Pharma Corporation, MSD, Ono Pharmaceutical, Pfizer, Roche, Takeda Pharmaceutical, Teijin Pharma, and UCB, Hiroaki Nakamura Grant/research support from: Astellas Pharma Inc. and Asahi Kasei Pharma Co.

AB0265 REDUCTION OF APPENDICULAR SKELETAL MASS INDEX IS A PREDICTOR OF FRACTURE IN PATIENTS WITH RHEUMATOID ARTHRITIS BASED ON THE THREE-YEAR FOLLOW-UP DATA OF THE CHIKARA STUDY

Background:

Patients with rheumatoid arthritis (RA) have lower muscle mass1and a higher risk of fragility fracture2compared with healthy individuals. The predictors for fractures among baseline data and the chronological changes of disease activity, body composition, and muscle mass are unknown.

Objectives:

The predictors for fractures were investigated over a 3-year period in a longitudinal study.

Methods:

The 3-year follow-up data from a prospective observational study (CHIKARA study: Correlation researcH of sarcopenIa, sKeletal muscle and disease Activity in Rheumatoid Arthritis) were used. The patients’ fractures were counted, and correlations between fractures and disease activity, body composition, and sarcopenia were investigated. Muscle mass, body fat mass, total body water, bone mass, and basal metabolic rate were measured using a body composition analyzer. The fracture-free survival rate was calculated. The relationships between fractures and each parameter at baseline and the changes over the 3-year period (Δ) were investigated by univariate and multivariate analyses.

Results:

A total of 100 patients (78 female, average age 68 years) were enrolled in this study; 12 patients (10 female and 2 male) had fractures during the 3-year follow-up, and the fracture-free survival rate was 86.9%. The Δmodified Health Assessment Questionnaire (mHAQ), Δweight, Δmuscle mass, Δestimated bone mass, Δbasal metabolic rate, and Δappendicular skeletal muscle index (ASMI) were predictors for fractures. On the other hand, body composition, disease activity, and sarcopenia at baseline were not correlated with fractures (Table 1). The ΔASMI was an independent predictor for fractures on multivariate analysis (odds ratio:0.015, P=0.026). The estimated cut-off value of the ΔASMI was 0.14 kg/m2on receiver operating characteristic curve analysis (Figure). When the ΔASMI decrease was greater than or equal to 0.14 kg/m2for three years, the odds ratio of fractures was significantly increased 9.8-fold, compared to a ΔASMI decrease less than 0.14 kg/m2(P=0.001).

Table 1.

Predictors for fractures in patients with RA

UnivariateR valueP valueBaselineAge, year0.1720.087DAS28-ESR-0.0830.411mHAQ0.0770.447Weight, kg0.0210.837Muscle mass, kg-0.00350.728Estimated bone mass, kg-0.0200.845Sarcopenia-0.0930.356Change of 3-year periodΔDAS28-ESR0.1870.088ΔmHAQ0.2240.040ΔWeight, kg-0.2240.045ΔMuscle mass, kg-0.2530.023ΔEstimated bone mass, kg-0.2360.034ΔBasal metabolic rate, kcal/day-0.2480.025ΔAppendicular skeletal muscle index, kg/m2-0.3520.001

Conclusion:

The fracture-free survival rate was 86.9% in this 3-year longitudinal study. It was difficult to predict future fractures from the baseline data. Reduction of the ASMI was an independent predictor for fractures. Alleviating muscle mass loss may prevent fractures.

References:

[1]Inui K., Koike T., Tada M., et al. Sarcopenia is apparent in patients with rheumatoid arthritis, especially those with biologics -TOMORROW study-.EULAR2015 abstract (AB0359).

[2]van Staa TP, Geusens P, Bijlsma JW, et al. Clinical assessment of the long-term risk of fracture in patients with rheumatoid arthritis.Arthritis Rheum.2006; 54: 3104–12.

Disclosure of Interests:

None declared

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.