Unveiling Predictive Parameters for Rheumatoid Arthritis Development in Arthralgia Patients: Insights from a Prospective Longitudinal Study

Abstract

Background: Early diagnosis of rheumatoid arthritis (RA) is crucial for timely intervention and improved outcomes. Although research on the preclinical phase of RA is a prominent topic, there remains an unmet need to effectively stratify patients at risk of developing RA based on basic clinical assessment and laboratory investigations. This prospective longitudinal study aimed to identify risk factors for RA development in individuals experiencing arthralgia. Method: Two hundred consecutive adults with arthralgia were enrolled from new referrals to our rheumatology clinic. Patients with synovitis or a known arthritis diagnosis were excluded. Follow-up assessments were conducted every 6 months, or sooner if symptoms worsened, for a maximum of 2 years. The study endpoint was the development of RA, according to the 2010 ACR/EULAR classification criteria. Baseline demographic characteristics, clinical parameters, serology, and acute phase reactant levels were compared between patients who developed RA and those who did not. In addition, the classification score based on the 2010 ACR/EULAR classification criteria was utilised as a composite weighted score summarising the clinical presentation in the cohort, although the patients were deemed not fulfilling the mandatory criteria of having synovitis at baseline. Results: By May 2024, 104 patients had been followed up for at least one year, with a median duration of 78 weeks (IQR: 58-97). The baseline symptom duration was 51 weeks (IQR: 29 – 97). Among these patients, 23 (22.1%) developed RA after a median follow-up duration of 41 weeks (IQR: 25 – 52). Patients who developed RA had a significantly higher proportion of joint symptoms <1 year, difficulty making a fist, positive rheumatoid factor (RF), anti-CCP antibodies, and elevated ESR and CRP levels at baseline. Multivariate logistic regression identified difficulty making a fist (OR: 4.87, 95% CI: 1.40 – 17.04, p = 0.013) and positive anti-CCP antibodies (OR: 13.04, 95% CI: 3.74 – 45.44, p < 0.001) as independent predictors for RA development. Meanwhile, patients who developed RA had significantly higher baseline scores extrapolating from the 2010 ACR/EULAR classification criteria compared to the non-RA group. Conclusion: Difficulty making a fist and positive anti-CCP antibodies are independent predictors of RA development. Additionally, patients who developed RA exhibited significantly higher baseline scores on the 2010 ACR/EULAR classification criteria. Early recognition of these variables and taking reference from the score of classification criteria may aid in RA risk stratification. Further research is needed to validate these findings and explore additional predictive markers.