POS1059 ULTRASOUND SYNOVITIS, UNLIKE ENTHESITIS OR CLINICAL JOINT ASSESSMENT, IS ASSOCIATED WITH JOINT DAMAGE PROGRESSION IN PATIENTS WITH PSORIATIC ARTHRITIS

Background:

We previously reported that ultrasound assessment of enthesitis (US enthesitis) is not consistent with tenderness of the enthesis (clinical enthesitis) in patients with psoriatic arthritis (PsA). Although US enthesitis reflects inflammatory condition and clinical enthesitis is associated with disease activity and physical function, each of them was not associated with joint destruction by cross-sectional analysis1. It is reported that the utility of US for predicting joint destruction remains unclear among patients with PsA2.

Objectives:

This study is aimed to longitudinally investigate the relationships between enthesitis or synovitis and joint damage progression in patients with PsA.

Methods:

Forty-seven patients with PsA (average age of 56.5 years) underwent US and clinical examination of wrist and finger joints and 14 entheses (the bilateral humeral medial epicondyles and insertions of the triceps, distal quadriceps, proximal/distal patella, Achilles tendons, and plantar fascia). Tender or swollen joint count (TJC/SJC), Gray Scale (GS) and Power Doppler (PD) score of the joints, and US/clinical enthesitis counts were calculated. The relationships between the yearly progression in modified total sharp score (ΔmTSS) at two-time points (baseline and average follow-up of 20.4 months) and US or clinical findings were investigated.

Results:

ΔmTSS was significantly correlated with age (r=0.44, p=0.01), joint GS score (r=0.44, p=0.01), and joint PD score (r=0.38, p=0.03). TJC, SJC, inflammatory marker, and disease activity showed no associations with ΔmTSS. US/clinical enthesitis counts also showed no associations with ΔmTSS (Table 1). The joint PD score, adjusted by age, was significant factor for ΔmTSS by multiple regression analysis (b=0.50, p<0.001).

Conclusion:

The joint PD score or US synovitis, unlike clinical joint assessment, was significant predictive factor for joint damage progression. It is important to assess joints by US as well as clinical examination.

References:

1) Yutaro Yamada et al. Ultrasound assessment, unlike clinical assessment, reflects enthesitis in patients with psoriatic arthritis. Clin Exp Rheumatol. 2020 Apr 17. Online ahead of print.

2) van der Heijde et al. Assessing structural damage progression in psoriatic arthritis and its role as an outcome in research. Arthritis Res Ther. 2020, 22(1): 18.

Table 1.

Univariate analysis of predictive factors for joint damage progression in PsA patients.

mTSS at baselineΔmTSSR valuep valueR valuep valueage0.55<0.0010.440.01PASE0.040.810.120.52PASI-0.250.15-0.010.96DAS28CRP-0.050.750.070.71DAPSA-0.010.94-0.010.97HAQ0.170.27-0.070.73CRP-0.130.380.230.20MMP-30.040.800.290.12biologics use0.190.19-0.110.54Clinical enthesitis counts-0.010.97-0.190.30TJC-0.050.76-0.100.58SJC0.210.180.130.48US enthesitis counts0.120.44-0.130.48joint GS score0.080.600.440.01joint PD score0.080.600.380.03

PsA: psoriatic arthritis, mTSS: modified Total Sharp Score, PASE: Psoriatic Arthritis Screening and Evaluation, PASI: Psoriasis Area Severity Index, DAPSA: Disease Activity in Psoriatic Arthritis, DAS: Disease Activity Score, CRP: C-reactive protein, HAQ: Health Assessment Questionnaire, MMP-3: matrix metalloproteinase 3, TJC: tender joint counts, SJC: swollen joint counts, GS: Gray Scale, PD: Power Doppler

Disclosure of Interests:

Yutaro Yamada: None declared, Kentaro Inui Speakers bureau: Abbvie, Eisai, Eli Lilly, Grant/research support from: Abbvie, Eisai, Chigai, Eli Lilly, Daiichi Sankyo, Mitusbishi Tanabe, Pfizer, UCB, Tadashi Okano Speakers bureau: Abbvie, Koji Mandai: None declared, Kenji Mamoto: None declared, Tatsuya Koike Grant/research support from: Abbvie, Chugai, Chiharu Tateishi: None declared, Daisuke Tsuruta Speakers bureau: Abbvie, Astellas, Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Novartis, Sanofi, Grant/research support from: Abbvie, Eli Lilly, Bristol-Myers Squibb, UCB, Hiroaki Nakamura Grant/research support from: Astellas, Asahi Kasei

AB0813 DEVELOPING SARCOPENIA IS A RISK FACTOR FOR FRACTURES IN PATIENTS WITH RHEUMATOID ARTHRITIS: 4-YEAR DATA FROM THE CHIKARA STUDY

Background:

Patients with rheumatoid arthritis (RA) tend to have sarcopenia due to decreased muscle mass and function. We previously reported that 13.2% of RA patients without sarcopenia at baseline developed sarcopenia over a year using data from the prospective, observational CHIKARA study1.

Objectives:

The aim was to investigate sarcopenia status and the characteristics of RA patients longitudinally.

Methods:

Body composition, laboratory data, disease activity, physical function, treatment, and history of falls and fractures were investigated in 100 RA patients who participated in the CHIKARA study at baseline and at 4 years. The patients were divided into 4 groups depending on their sarcopenia status: no sarcopenia development (N group), sarcopenia development (S group), cured (C group), and persisted (P group).

Results:

Of the 77 RA patients who completed the survey, 48 were in the N group; their body mass index, skeletal muscle mass index, fat percentage, estimated bone mass, and body metabolization rate at baseline were significantly elevated. On the other hand, 6 patients were in the S group; 83.3% of them experienced fractures during the 4 years, significantly more than in the other groups. Ten patients were in the P group, and their baseline MMP-3 was significantly higher than in the other groups. Thirteen patients were in the C group. There were no differences among the 4 groups in disease activity and physical function (Table 1).

Table 1.

Characteristics of 77 RA patients by sarcopenia status at baseline and at 4-year follow-up.

no development(n=48)development(n=6)cured(n=10)persisted(n=13)p valueBaseline age, years64.5 (57.8, 72)70.0 (65.5, 72.3)61.0 (54.5, 68.3)72 (68, 81)0.062 disease duration, years4.6 (1.1, 9.9)11.7 (2.8, 18.9)8.1 (4.2, 14.3)4.0 (2.2, 7.7)0.427 biologics use, %37.516.730.023.10.617 GC use, %27.116.710.023.10.678 MMP-3, ng/ml66.8 (51.8, 103)52.5 (40.0, 56.7)82.8 (57.8, 186)157.5 (90.8, 250)0.001 DAS28ESR3.43 ± 0.873.48 ± 1.323.36 ± 1.083.80 ± 1.270.661 mHAQ0.31 (0, 0.50)0.19 (0.03, 0.44)0.38 (0, 0.84)0.50 (0.25, 0.88)0.383 BMI, kg/m223.4 ± 3.621.6 ± 2.419.2 ± 1.619.5 ± 2.6<0.001 SMI, kg/m26.8 ± 0.86.2 ± 0.65.8 ± 0.55.7 ± 0.6<0.001 fat percentage, %30.4 ± 8.429.1 ± 9.123.9 ± 4.025.1 ± 8.30.046 estimated bone mass, kg2.2 (2.0, 2.4)1.9 (1.8, 2.1)2.0 (1.7, 2.1)1.7 (1.7, 1.9)0.012 BMR, kcal1100 (1031, 1197)1029 (918, 1070)1012 (917, 1057)934 (894, 1006)0.005Change during 4 years ΔDAS28ESR-0.34 ± 0.97-0.52 ± 0.98-0.60 ± 1.46-0.56 ± 1.140.834 ΔmHAQ0 (-0.25, 0.16)0.19 (0, 0.56)-0.06 (-0.44, 0.94)0 (-0.38, 0.38)0.357 ΔSMI, kg/m20.0 ± 0.3-0.6 ± 0.30.3 ± 0.4-0.0 ± 0.3<0.001 fall, %43.883.330.023.10.079 fracture, %14.683.320.023.10.002

Data are shown as mean ± standard deviation (SD) or median (25th, 75th percentile).

GC: glucocorticoids, BMI: body mass index, SMI: skeletal muscle mass index, BMR: body metabolization rate.

Conclusion:

Overall, 7.8% of RA patients developed sarcopenia during the 4-year follow-up period, and they developed fractures more frequently. Evaluation of sarcopenia is important for risk assessment of fractures.

References:

[1]Y Yamada, M Tada, K Mandai et al. Glucocorticoid use is an independent risk factor for developing sarcopenia in patients with rheumatoid arthritis: from the CHIKARA study. Clin Rheumatol 2020 Jun;39(6):1757-1764.

Disclosure of Interests:

Yutaro Yamada: None declared, Masahiro Tada: None declared, Koji Mandai: None declared, Noriaki Hidaka: None declared, Hiroaki Nakamura Grant/research support from: Astellas and Asahi Kasei

POS0517 A LONGITUDINAL STUDY OF SARCOPENIA, LOCOMOTIVE SYNDROME, AND FRAILTY IN PATIENTS WITH RHEUMATOID ARTHRITIS: FROM THE CHIKARA STUDY

Background:

Rheumatoid arthritis (RA) patients have a high frequency of sarcopenia, and they commonly have reduced physical function. We previously reported that the prevalence of sarcopenia was 28%, that of frailty was 18.9%, and that of pre-frailty was 38.9% in RA patients1,2, and 13.2% of RA patients developed sarcopenia within a year 3.

Objectives:

To investigate the risk factors for new onset of sarcopenia, locomotive syndrome, and frailty in patients with RA and the course of each disease.

Methods:

Two-year follow-up data from the rural group of the prospective, observational CHIKARA study were used. Sarcopenia was diagnosed using the criteria of the Asian Working Group for Sarcopenia 2014, locomotive syndrome was diagnosed using locomotive 5, and frailty was diagnosed using the basic checklist. New onset of the disease over the 2-year follow-up period was studied, excluding cases that had the disease at baseline. Improvement was defined as cases with disease at baseline that no longer met the diagnostic criteria after 2 years. Differences in the characteristics of each disease were tested using the Chi-squared test and the paired t-test.

Results:

The 81 patients with RA (82.7% female) had mean age 66.9±11.5 years, mean DAS28-ESR 2.9±1.2, methotrexate use in 81.5% (with a dose of 9.9±2.7 mg/week), and glucocorticoid (GC) use in 22.2% (with a dose of 3.1±1.7 mg/week). The baseline prevalence was 44.4% for sarcopenia, 35.8% for locomotive syndrome, and 25.9% for frailty, and the new onset rate was 4.4% for sarcopenia, 15.4% for locomotive syndrome, and 13.3% for frailty. Of the patients with each disease at baseline, 36.1% had sarcopenia, 20.7% had locomotive syndrome, and 33.3% had frailty, and of those with each disease at 2 years, 36.1% had sarcopenia, 20.7% had locomotive syndrome, and 33.3% had frailty. The new onset sarcopenia and locomotive syndrome groups had significantly higher rates of GC use (p=0.036, p=0.007, paired t-test) and significantly higher doses (p=0.01, p=0.001, paired t-test) than the groups without new onset sarcopenia and locomotive syndrome. High baseline disease activity was an independent predictor of new onset of locomotive syndrome on multivariate logistic regression analysis (OR=3.21, p=0.015).

Conclusion:

The new onset rates at 2 years were 4.4% for sarcopenia, 15.4% for locomotive syndrome, and 13.3% for frailty. In the new onset sarcopenia and locomotive syndrome groups, both GC use and dosage were significantly higher.

References:

[1]Tada M, et al. Matrix metalloprotease 3 is associated with sarcopenia in rheumatoid arthritis - results from the CHIKARA study. Int J Rheum Dis. 2018 Nov;21(11):1962-1969.

[2]Tada M, et al. Correlation between frailty and disease activity in patients with rheumatoid arthritis: Data from the CHIKARA study. Geriatr Gerontol Int. 2019 Dec;19(12):1220-1225.

[3]Yamada Y, et al. Glucocorticoid use is an independent risk factor for developing sarcopenia in patients with rheumatoid arthritis: from the CHIKARA study. Clin Rheumatol. 2020 Jun;39(6):1757-1764.

Disclosure of Interests:

None declared

AB0115 COMPARISON OF ULTRASOUND FINDINGS BETWEEN TNF INHIBITORS AND NON-TNF INHIBITORS AT FIRST BIOLOGICS IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

In rheumatoid arthritis (RA), biologics treatment is one of the effective treatment options. Usually, there is no difference in therapeutic effect regardless of which biologics is used, but the effect for joint synovitis is unknown. Recently, ultrasound (US) has played a role of sensitive imaging modality in the diagnosis and follow-up of patients with RA.

Objectives:

The aim of this study was to compare the improvement of US findings between TNF inhibitors and non-TNF inhibitors at first biologics in patients with RA.

Methods:

Fifty-four RA patients who started the first biologics from September 2016 to December 2018 were included in this longitudinal study (SPEEDY study, UMIN000028260). All the patients were performed clinical examination, blood test and US examination at baseline, 4, 12, 24, 36 and 52 weeks. A US examination was performed at the bilateral first to fifth metacarpophalangeal (MCP) joints, first interphalangeal (IP) and second to fifth proximal interphalangeal (PIP) joints, wrist joints (three part of radial, medial and ulnar) and first to fifth metatarsophalangeal (MTP) joints, by using HI VISION Ascendus (Hitachi Medical Corporation, Japan) with a multifrequency linear transducer (18-6 MHz). The gray scale (GS) and power Doppler (PD) findings were assessed by the semi-quantitative method (0-3). GS score and PD score (both 0-108 points) were defined as the sum of each score. The change of disease activity and US findings were compared between TNF group and non-TNF group.

Results:

Among 54 cases, 32 patients were used TNF inhibitor and 22 were non-TNF inhibitor. Age and duration of RA were significantly higher in the non-TNF group, and MTX dose was significantly lower in the non-TNF group. The baseline inflammatory markers tended to be higher in the non-TNF group and the disease activity was also higher in the non-TNF group. However, the US findings showed no significant difference in both GS and PD between two groups at baseline. US improvement ratio was no difference between TNF group and non-TNF group at 4, 12, 24, 36 and 52 weeks in both GS and PD score. Regardless of the type of biologics, patients with long-term disease duration tended to have poor improvement in US synovial fingings.

Table 1.

Baseline patient and disease characteristics

TNF (n=32)non-TNF (n=22)P valueFemale patients, n (%)21 (65.6)16 (72.7)0.767Age (years)63.5±15.471.0±9.00.030Disease duration (years)6.5±8.213.0±11.70.032CRP (mg/dl)1.8±2.53.0±3.20.170DAS28-ESR5.0±1.45.8±1.20.022GS score26.1±18.831.8±21.10.313PD score17.6±11.423.1±14.60.150Figure 1.

GS and PD improvement ratio at 4, 12, 24, 36 and 52 weeks

Conclusion:

There was no difference in the US findings improvement between patients with TNF inhibitor and non-TNF inhibitor at first biologics in patients with RA.

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]Nishino A, Kawashiri SY, Koga T, et al. Ultrasonographic Efficacy of Biologic andTargeted Synthetic Disease-ModifyingAntirheumatic Drug Therapy in RheumatoidArthritis From a Multicenter RheumatoidArthritis Ultrasound Prospective Cohort in Japan. Arthritis Care Res (Hoboken). 2018;70:1719-26.

Acknowledgements:

We wish to thank Atsuko Kamiyama, Tomoko Nakatsuka for clinical assistant, Setsuko Takeda, Emi Yamashita, Yuko Yoshida, Rika Morinaka, Hatsue Ueda and Tomomi Iwahashi for their special efforts as a sonographer and collecting data.

Disclosure of Interests:

None declared

POS0514 IMPORTANCE OF BODY MASS MEASUREMENT AND THE GRIP STRENGTH TEST TO PREDICT FALLS IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

We previously reported that the prevalence of sarcopenia was 28% in patients with rheumatoid arthritis (RA) in a cohort study 1. RA patients have a high risk of falls and fractures 2. However, the predictors of falls and fractures in RA patients are not known.

Objectives:

Whether evaluation of muscle mass and function at baseline could predict falls and fractures during four-year follow-up was investigated.

Methods:

The four-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. Muscle mass was measured by a body impedance analyzer, and leg muscle mass was calculated. The leg muscle score (max: 100, min: 0) reflected the ratio of leg muscle mass to overall weight. Grip strength as an indicator of muscle function was evaluated using a digital, hand-held, isokinetic dynamometer. The correlations between muscle mass or function and falls or fractures were analyzed by survival rates and Cox hazard ratios. Leg muscle mass and grip strength were investigated by receiver operating characteristic (ROC) curve analysis for correlations with falls or fractures.

Results:

A total of 100 RA patients (female: 78%, mean age: 66.1 years) were enrolled; 35 patients had falls, and 19 patients had fractures during the four-year follow-up. The leg muscle score, grip strength, age, and fractures at baseline were significantly correlated with falls. The cut-off values of the leg muscle score and grip strength were calculated to be 84.5 points (sensitivity: 0.79, specificity: 0.43) and 15.9 kg (sensitivity: 0.56, specificity: 0.70), respectively, by ROC curve analysis. The patients were divided into four groups by their leg muscle scores and grip strength; the numbers of falls and fractures are shown in Table 1 for each group. The fall-free survival rate was significantly lower in the group with low leg muscle score and low grip strength (35.3%) than in the other groups (P=0.002) (Figure 1). The hazard ratio for the both low group was significantly increased, 3.6-fold (95%CI: 1.1-11.5), compared to that in the both high group.

Table 1.

Numbers of falls and fractures by category of leg muscle score and grip strength

LG + GS+(n=34)LG - GS+(n=12)LG + GS-(n=37)LG - GS-(n=17)P value*Falls, N6515110.010Fractures, N34660.072

LG+: leg muscle score >84.5 points, GS+: grip strength >15.9kg, LG-: leg muscle score ≤84.5 points, GS+: grip strength ≤15.9kg

*: compared in four groups by Kruskal-Walls test.

Figure 1.

Fall-free survival rate in the four groups

Conclusion:

RA patients with both low leg muscle score and low grip strength at baseline were at high risk for falls during the four-year follow-up period. Evaluation of muscle mass and function can predict falls in RA patients.

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]van Staa, T. P., Geusens, P., Bijlsma, J. W., Leufkens, H. G. & Cooper, C. Clinical assessment of the long-term risk of fracture in patients with rheumatoid arthritis. Arthritis Rheum54, 3104-3112, doi:10.1002/art.22117 (2006).

Disclosure of Interests:

None declared

OP0319 OSTEOSARCOPENIA INCREASES THE RISK OF FALLS IN PATIENTS WITH RHEUMATOID ARTHRITIS: RESULTS OF A FOUR-YEAR LONGITUDINAL STUDY

Background:

Osteosarcopenia is defined as osteoporosis combined with sarcopenia. Both osteoporosis and sarcopenia are risk factors for falls and fractures in healthy individuals1. The relationships of falls and fractures to osteosarcopenia in rheumatoid arthritis (RA) patients are unknown.

Objectives:

The synergistic effect of osteoporosis and sarcopenia and the impact of osteosarcopenia on falls and fractures in RA patients were investigated using four years of data from a longitudinal study.

Methods:

The data from a prospective, observational study (CHIKARA study: UMIN000023744) were examined. The patients were divided into four groups according to their baseline status: no sarcopenia and osteoporosis (SP-OP-); only sarcopenia (SP+OP-); only osteoporosis (SP-OP+); and both sarcopenia and osteoporosis (SP+OP+). Sarcopenia was diagnosed by the criteria of the Asia Working Group on Sarcopenia 20142. Patients with osteoporosis were defined as those having a therapeutic intervention for osteoporosis. The survival rate and Cox hazard ratio were analyzed using falls and fractures as endpoints, adjusted by age, sex, and body mass index.

Results:

A total of 100 RA patients (female 78%, mean age 66.1 years) were enrolled. The number of SP-OP-, SP+OP-, SP-OP+, and SP+OP+ patients was 45, 17, 27, and 11, respectively. Their baseline characteristics are shown in Table 1. A total of 35 patients had falls, and 19 patients had fractures during the four-year follow-up. The fall-free survival rate in the SP-OP-, SP+OP-, SP-OP+, and SP+OP+ groups was 75.6%, 64.7%, 51.9%, and 36.4%, respectively; that of the SP+OP+ group was significantly lower than that of the other groups (P=0.021) (Figure 1). The fracture-free survival rate in the SP-OP-, SP+OP-, SP-OP+, and SP+OP+ groups was 86.7%, 82.4%, 81.5%, and 54.5%, respectively. That of the SP+OP+ group was relatively lower than that of the other groups (P=0.121). The hazard ratio of falls was significantly increased in the SP+OP+ group by 3.32-fold (95%CI: 1.01-10.9) compared to that in the SP-OP- group, whereas that in the SP+OP- and SP-OP+ groups was 2.58-fold (95%CI: 0.75-8.8) and 2.29-fold (95%CI: 0.94-5.6) higher, respectively. There were no significant differences compared to the SP-OP- group. The hazard ratio of fractures in the SP+OP+ group was increased 2.73-fold (95%CI: 0.61-12.2) compared to that in the SP-OP- group.

Table 1.

Baseline characteristics of the four groups

SA-OP-SA+OP-SA-OP+SA+OP+P value*Female, %73.358.888.91000.027Age, years63 (49, 72)69 (60, 79)73 (64, 75)73 (65, 81)0.008Disease duration, years4.4 (1.0, 8.4)4.0 (1.3, 8.9)7.6 (1.5, 14.5)10.5 (3.2, 26.5)0.035DAS28-ESR3.14 (2.66, 3.70)3.55 (3.01, 4.65)3.93 (3.28, 4.63)3.53 (2.48, 3.89)0.01mHAQ0.25 (0, 0.375)0.375 (0.125, 0.875)0.375 (0.125, 0.875)0.5 (0.125, 0.875)0.065MTX, mg/week, rate (%)8.4 ± 2.9 (86.7)8.7 ± 3.5 (70.6)8.3 ± 2.8 (92.6)6.8 ± 1.0 (90.9)0.388Glucocorticoid, mg/day, rate (%)3.7 ± 1.9 (20.0)6.3 ± 1.8 (11.8)4.0 ± 1.7 (44.4)3.8 ± 1.8 (18.2)0.400Body mass index, kg/m223.4 ± 3.819.2 ± 2.321.7 ± 2.419.2 ± 2.0<0.001

Data are shown as mean ± standard deviation (SD) or median (25th, 75th percentile).

*: compared in four groups by Kruskal-Walls test.

Figure 1.

Fall-free survival rates of the four groups.

Conclusion:

The survival rates with the endpoints of falls and fractures in RA patients with osteosarcopenia were lower during the four-year follow-up. In particular, the risk of falls increased with the synergistic effect of osteoporosis and sarcopenia in RA patients.

References:

[1]Dennison, E. M. et al. Fracture risk following intermission of osteoporosis therapy. Osteoporos Int30, 1733-1743, doi:10.1007/s00198-019-05002-w (2019).

[2]Chen, L. K. et al. Sarcopenia in Asia: consensus report of the Asian Working Group for Sarcopenia. J Am Med Dir Assoc15, 95-101, doi:10.1016/j.jamda.2013.11.025 (2014).

Disclosure of Interests:

None declared.

POS0466 RHEUMATOID ARTHRITIS PER SE IS NOT RISK FACTOR FOR CLINICAL FRACTURES: NINE-YEAR FINDINGS OF THE TOMORROW STUDY

Background:

Patients with rheumatoid arthritis (RA) who have sarcopenia and stiff or painful joints might be at increased risk of falls and fractures.

Objectives:

The present study aimed to prospectively identify the incidence of clinical fractures and associated risk factors in patients with RA in a cohort study named the TOMORROW (UMIN000003876) that started in 2010.

Methods:

We evaluated anthropometric parameters, bone mineral density (BMD), disease activity, RA medication at baseline and observed the incidence of clinical fractures during nine years in 202 patients with RA (mean age, 58.6 y; medication with biological agents, 54.9%) and 202 age- and sex-matched non-RA volunteers (mean age, 57.4 y). We compared the incidence of clinical fractures between patients with RA and controls for nine years, and analyzed the risk factors for fractures using Cox proportional hazard model.

Results:

The incidence of clinical fractures in RA patients was significantly higher compared to controls (27.5 vs 18.3%, p=0.04). However, Cox proportional hazard model, adjusted by age, sex, smoking and body mass index, revealed that low BMD at thoracic vertebrae (< 0.7 g/cm2) significantly associated to the incidence of clinical fractures (hazard ratio [HR], 1.86, p=0.02), but not RA morbidity (HR 1.47, p=0.10) (Table 1). Among patients with RA, low BMD at the thoracic vertebrae (< 0.7 g/cm2) was the most prominent risk factor for clinical fractures (HR, 2.66, p=0.02) (Table 1). Although the use of glucocorticoid (GC) at baseline (HR, 1.68, p=0.09) was not a significant risk factor for fractures, a mean GC dose (≥ 2 mg/day) at entry increased risk for clinical fractures in the patients (HR, 1.91, p=0.04) (Table 1).

Conclusion:

RA per se was not a risk factor for clinical fractures in this cohort. Low BMD at the thoracic vertebrae and the use of GC with even low dose at entry were apparently significant risk factors for the incidence of clinical fractures among patients with RA.

Disclosure of Interests:

Kenji Mamoto: None declared, Tatsuya Koike Grant/research support from: Takeda Pharmaceutical, Mitsubishi Tanabe Pharma Corporation,

Chugai Pharmaceutical, Eisai, Abbott Japan, Teijin Pharma, Banyu Pharmaceutical and Ono Pharmaceutical, Yutaro Yamada: None declared, Tadashi Okano: None declared, Yuko Sugioka: None declared, Masahiro Tada: None declared, Kentaro Inui 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., 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., Hiroaki Nakamura: None declared

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&lt;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

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 &gt;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&lt;2.0×10–16 for T2DM, P=9.1×10–11 for FPG), rs78338345 of GGA3 (P&lt;2.0×10–16 for T2DM, P=4.3×10–9 for FPG), rs10490775 of PTPRG (P&lt;2.0×10–16 for T2DM, P=3.3×10–7 for FPG), and rs61739510 of GLT6D1 (P&lt;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