Predictors of Remission in New-Onset Inflammatory Polyarthritis

Among patients with inflammatory polyarthritis (IP), factors that are predictive of a lower likelihood of reaching remission include female sex, baseline higher tender joint count or disability, depression, obesity, and hypertension, according to a study recently published in Rheumatology.

The goal of achieving early and sustained remission in IP is now within greater reach with the availability more effective treatments and early, goal-directed regimens. But remission rates vary widely and factors that denote a greater likelihood of remission have not been clearly established. Prior studies examining predictors of remission had shorter periods of follow-up, with most only evaluating remission at a single time point usually at the end of the study.

Michael J. Cook, PhD, of the University of Manchester, and colleagues sought to determine which factors predicted sustained, intermittent, or never remission in patients with IP from the Norfolk Arthritis Register over a longer follow-up period of 5 years.

Remission status was assessed in 868 patients at years 1, 2, 3, and 5. Sustained remission (SR) was defined as no evidence of tender or swollen joints out of a 51-joint count on at least 3 consecutive assessments. 

Never remission (NR) was no remission at any assessment. Patients who did not classify as SR or NR were considered to be in intermittent remission (IR).

Nearly half (54%) of patients never achieved remission, and 46% achieved remission at one or more time points over 5 years (34% IR, 12% SR).

Women were less likely to achieve remission than men (odds ratio [OR], 0.47; 95% confidence interval, 0.35 to 0.63), and gender was the strongest predictor for remission.

Other factors associated with lower chances of remission included hypertension (OR, 0.67), depression (OR, 0.74), obesity (OR, 0.70), higher Health Assessment Questionnaire score (OR, 0.59), and higher tender joint count (OR, 0.94).

Early use of disease-modifying antirheumatic drugs (within 3 months of symptom onset) was a positive predictor for remission in the univariate but not the multivariate analysis.

Summary and Clinical Applicability

An analysis of patients with IP in the Norfolk Arthritis Register found that predictors for a lower likelihood of remission included female sex, baseline higher tender joint count or disability, depression, obesity, and hypertension.

“Having a 5-year follow-up allowed us to identify baseline factors associated with IR and SR, rather than factors associated with remission at a single point in time,” the authors wrote. “These factors may be useful in predicting which patients are likely to achieve remission and, thus, in guiding treatment choice and timing.”

Limitations and Disclosures

• Definition of remission did not include blood markers of inflammation, which may have misclassified patients who were in remission but had tender joints from other causes

• Identification of comorbidities, such as depression and hypertension, relied on patient self-reporting

• Obesity was defined using body mass index, while using hip-to-waist ratio or whole-body MRI may have been more accurate in the IP population

This study was funded by GlaxoSmithKline. The authors report no relevant conflicts of interest.