Study Finds Link Between Ultrasounds, PROs in Patients With RA, Low Disease Activity

Residual inflammation on ultrasound images was associated with patient-reported outcomes in patients with rheumatoid arthritis (RA) with low disease activity (LDA), according to a study published in BMC Rheumatology. However, this residual inflammation was not seen in patients in remission (REM).

The researchers performed musculoskeletal ultrasonography (MSUS) on 300 patients with RA who received routine care at Tobata General Hospital in Kitakyushu, Japan. The team did a cross-sectional analysis on each patient by disease activity.

"In recent years, with improvements in the treatment of RA making it possible to achieve treatment goals, the management of patients’ subjective symptoms has received more attention in the context of patient-centred care," the authors explained.

The mean age was 65.4 years and 80.7% of participants being female. The mean disease duration was 103.6 months, or 8.6 years. The patients included had received at least one disease-modifying antirheumatic drug (DMARD) continuously for at least 24 weeks.

The researchers performed systematic multiplanar grayscale (GS) and power Doppler (PD) ultrasound examinations on 22 joints in a standardized manner based on EULAR guidelines. They measured disease activity using the Simplified Disease Activity Index (SDAI), functional impairment using the Health Assessment Questionnaire Disability Index (HAQ-DI), and evaluated quality of life (QoL) using the European Quality of Life-5 Dimensions (EQ-5D-5L) questionnaire.

They performed univariate and multivariate analyses by dividing the data by disease activity and then by those who achieved LDA and those who did not. Overall, 96 patients were classified into the LDA group and 99 in the REM group. The researchers then analyzed each patient-reported outcome in the MSUS results.

Each joint was given a GS score using a semiquantitative scale of 0-3, defined as follows:

• Grade 0, absence of synovial hypertrophy on GS, no synovial thickening
• Grade 1, mild or minimal synovial thickening filling the angle between the periarticular bones without bulging over the line linking the tops of the bones
• Grade 2, moderate synovial thickening bulging over the line linking the tops of the periarticular bones, but without extension to at least one bone diaphysis
• Grade 3, marked synovial thickening bulging over the line linking the tops of the periarticular bones and with extension to at least one of the bone diaphysis

The researchers also gave PD scores based on a semiquantitative scale of 0-3, defined as follows:

1. Grade 0, no PD signal and no synovial flow
2. Grade 1, mild, single-vessel signal
3. Grade 2, moderate, confluent signal in less than half of the synovial area
4. Grade 3, marked PD signal in more than half of the synovial area

The univariate analysis identified several significant factors, including MTX usage rate and dose, both tender (TJC) and swollen joint count, both pain and fatigue visual analog scale score (VAS), morning stiffness, HAQ, EQ-5D-5L, and estimated gestational age. Total GS score, GS score ≥ 1, GS score ≥ 2, total PD score, and PD score ≥ 1 were also major factors.

The subsequent multivariate analysis identified TJC and fatigue VAS as independent significant factors.

“For patients with LDA not achieving REM, it was suggested that fatigue VAS score and TJC may remain,” the authors noted. “In patients who achieved REM, little residual inflammation was observed on MSUS.”

This study identified GS score ≥ 2 as an independent factor for patients who achieved LDA during treatment, but showed persistent inflammation after treatment. The results also showed a relationship between GS ≥ 2 and patient-reported outcomes.

“In our study, patients with RA who achieved LDA or clinical REM experienced residual symptoms, including pain, fatigue, morning stiffness, mental health, and functional disability, possibly due to inflammation or other psychological effects of the disease itself,” the authors concluded. “Thus, our study is consistent with several studies on residual symptoms experienced by patients with RA who achieved LDA and clinical REM.”

Reference

Nawata M, Someya K, Funada M, et al. Association between ultrasound images and patient-reported outcomes in the treatment of rheumatoid arthritis: a retrospective study. BMC Rheumatol. Published online November 22, 2021. doi:10.1186/s41927-021-00221-3