Background/Purpose:  The presence of synovitis has been recognized as one of the most important predictive factors of subsequent structural damage in patients with rheumatoid arthritis (RA). We previously reported that the effects of low-dose etanercept (ETN) (25 mg/week) were not inferior to the effects of standard-dose ETN (50 mg/week) clinically, but in terms of the radiographic non-progression rate, the effects of low-dose ETN were inferior to the effects of standard-dose ETN in the PRECEPT study. It was considered that low-dose ETN may not be able to suppress inflammatory synovitis.The aim of this study was to compare ultrasonographic inflammatory synovitis between patients using standard- and low-dose ETN for RA.

Methods: Patients with RA receiving standard- and low-dose ETN underwent musculoskeletal ultrasonography (US) at 34 synovial sites (30 joints) in the following joints: bilateral first to fifth metacarpopharangeal (MCP) joints (dorsal recess), first interpharangeal (IP) and second to fifth proximal interpharangeal (PIP) (dorsal recess) joints, the wrists (dorsal radial, dorsal median, and dorsal ulnar) and second to fifth metatarsopharangeal (MTP) (dorsal recess) joints. The GS (Gray scale) and power PD (Power Doppler) signals were scored in each joint using a semiquantitative scale from 0 to 3. The GSUS and PDUS scores were compared with the sums of scores obtained for the 34 synovial sites and the maximum score between two groups.

Results: We analyzed 31 and 21 patients who received standard- and low-dose ETN, respectively. The overall comparison showed no significant differences between groups. However, when we analyzed patients in remission and low disease activity, the PDUS score and maximum PD score were significantly higher in the low-dose ETN group. In particular, the PDUS score in wrist were significantly higher in the low-dose ETN group. But, GSUS score showed no significant difference between two groups. (Table.1)

Table.1Clinical and demographic characteristics in patients in remission and low disease activity of DAS28-ESR

	ETN 25mg (n=11)	ETN 50mg (n=15)
Age (years old)	62.33	59.48	NS
Disease duration (years)	11.54	16.76	NS
Duration of ETN use  (years)	3.06	3.59	NS
Female (%)	72.73	100.0	NS
RF positive (%)	55.56	73.33	NS
ACPA positive (%)	66.67	91.67	NS
DAS28-ESR	2.62	2.30	NS
ESR (mm/hour)	12.55	19.27	NS
CRP (mg/dl)	0.18	0.14	NS
MMP-3 (ng/ml)	62.10	50.80	NS
mHAQ	0.29	0.23	NS
mTSS	142.44	158.93	NS
Total GSUS score	17.0	13.8	NS
Total PDUS score	7.91	4.20	P<0.05
Total PDUS score in finger	1.55	0.60	NS
Total PDUS score in wrist	5.82	3.33	P<0.01
Total PDUS score in foot	0.55	0.29	NS
Maximum PDUS score	1.73	1.13	P<0.01

Conclusion: Low-dose ETN is not inferior to standard-dose ETN in terms of effects on clinical assessment. However, in terms of ultrasonographic inflammatory synovitis, the effects of low-dose ETN may be inferior to the effects of standard-dose ETN. We consider that synovitis may not be suppressed sufficiently, and therefore joint destruction may progress, in RA patients receiving low-dose ETN.

References:

1. Tada M, Koike T, Okano T, et al. Comparison of joint destruction between standard- and low-dose etanercept in rheumatoid arthritis from the Prevention of Cartilage Destruction by Etanercept (PRECEPT) study. Rheumatology (Oxford). 2012 Dec: 51 (12) :2164-9.
2. Iagnocco A, Perella C, Naredo E, et al. Etanercept in the treatment of rheumatoid arthritis: clinical follow-up over one year by ultrasonography. Clin Rheumatol. 2008 Apr: 27 (4) :491-6.

---

« Back to 2013 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/comparison-of-effects-of-standard-and-low-dose-etanercept-on-inflammatory-synovitis-in-rheumatoid-arthritis-patients-as-assessed-by-ultrasonography/