About one-third of patients with clinically suspect arthralgia who do not develop RA have resolution of symptoms and subclinical joint inflammation on MRI by the end of 2 years, according to investigators from Leiden (the Netherlands) University.

“Thus far, most longitudinal studies performed in patients considered at risk for RA focused on the progression from arthralgia to RA, since (early) identification of individuals that will develop RA is a key point from a clinician’s perspective. However, there is also a group of patients that were considered at risk for RA but over time do not develop RA, meaning that, in hindsight, they possibly have not been truly ‘pre-RA’. This subgroup of patients is unexplored, and the course and outcome of joint symptoms and subclinical inflammation in these patients are yet unknown,” Robin M. ten Brinck and colleagues at Leiden wrote in Arthritis Research & Therapy.

The researchers followed 152 patients with clinically suspicious arthralgia (CSA) who did not develop RA during 2 years of follow-up. All patients had complete clinical data, and 98 had complete 2-year MRI data. Most of the 152 patients were women (74%), and they had a mean age of 47 years, a median of 5 tender joints (out of 68 evaluated), and 19% carried RA-related autoantibodies (rheumatoid factor and/or anti–citrullinated peptide antibody). None of the patients received disease-modifying antirheumatic drugs or glucocorticoids during the study; only NSAIDs were allowed.

Overall, 57 (38%) of the 152 reported resolution of symptoms by 2 years, including 32 (33%) of the 98 patients with serial MRI results available at 2 years. Of the remaining 95 patients who continued to have symptoms, 43 were diagnosed as having persistent CSA, 10 had osteoarthritis, and 13 had tendinomuscular complaints.

There was no statistically significant difference in mean baseline total MRI inflammation scores between those with and without symptom resolution, but among patients with a mean total MRI inflammation score greater than 0 at baseline, those who achieved resolution of symptoms over time had a mean score higher than that of symptom-free patients at baseline. Those patients with resolved symptoms also had a statistically significant decrease in MRI inflammation score at the 2-year follow-up. A smaller and not statistically significant decline in total MRI score was seen in patients without symptom resolution.

“Our study is the first to quantify the percentage of patients presenting with CSA that will have a resolution of symptoms over time. It consists of one-third of all nonprogressing patients and 27% of all patients that were identified as having CSA by rheumatologists,” the researchers wrote.

The study was sponsored by the European Research Council. The authors had no relevant disclosures.

SOURCE: ten Brinck RM et al. Arthritis Res Ther. 2020 Jan 16. doi: 10.1186/s13075-020-2102-9.