Background Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder that leads to an irreversible destruction of diarthrodial joints. Early diagnosis and treatment with disease-modifying antirheumatic drugs (DMARDs) are considered essential in order to achieve an optimal suppression of disease activity and prevent structural and functional deterioration. Biological therapy (BT) is the second-line treatment in case of inadequate response to DMARDs. BT has excellent safety and efficacy profiles. However, its economic burden is high.
Objectives The goal of our study was to identify clinical, epidemiological and analytical characteristics, as well as the delay of diagnosis, DMARD treatment, and inflammatory activity, associated with the need to initiate BT in RA patients.
Methods This is a single-center case-control study. We included patients who were diagnosed with RA from January 1, 2000, fulfilling the 2010 ACR/EULAR criteria. The main outcome (dependent variable) was the need for a first biological drug. The independent variables were time to diagnosis, time to treatment with the first DMARD, time to clinical remission, time to low activity, age, gender, number of swollen joints (NSJ) and tender joints (NTJ) at the time of diagnosis, positivity of RF and ACPA, CRP, ESR, radiologic erosions, smoking, body mass index, education level, and job status. The study was approved by the research ethical committee of our center. Descriptive statistics was used to present the results; chi-square test, Student t test, and Mann-Whitney U test were used to define statistical significance in the univariate analysis; and logistic regression for multivariate analysis. A P-value <0.05 was predefined as statistical significance. Statistical analyses were performed by using the SPSS v14.0.
Results One hundred and thirty-nine patients were included (mean age 53 years; 82% women; 83% white; 82% RF+; 74% ACPA+). Sixty-one patients (44%) had received BT. The univariate analysis demonstrated significant association between the need for BT and NTJ (p<0,001), NSJ (p=0,004), ESR (p=0,026), time to low disease activity (p<0,001) and time to remission (p<0,001). The multivariate logistic regression indicated that the NTJ at diagnosis, the time to low activity and the time to remission were independently associated with the need for BT during follow-up.
Conclusions In RA patients, the number of tender joints at the time of diagnosis and the time to low disease activity and clinical remission are associated with the need for BT during the course of the disease.
Disclosure of Interest None declared