To analyze the frequency and characteristics of dose reduction of biological agents in a cohort of patients with chronic arthritis, in clinical practice conditions in a tertiary level hospital.
Descriptive, cross-sectional study, which included all patients, followed consecutively during 6 months (June 2011-November 2011), by one investigator, with patients who at least have received one dose of biological agents in 2011.
We included 153 patients: Rheumatoid arthritis (RA) (n=82), ankylosing spondylitis (n=29), psoriatic arthritis (n=20), and miscellaneous group (n=22). Mean disease duration was 14.9±7.7 years. At the time of analysis, 70 patients (45.7%) were receiving low doses of biological therapy (50% in miscellaneous group group, 50% in psoriatic arthritis, 48.2% in ankylosing spondylitis, and 42.6% in RA). Mean time of dosage reduction was 17.4±17.5 months. The most common biological agents used in low dose were: etanercept, adalimumab and tocilizumab; 57.6%, 54.9% and 40% respectively, in patients with a reduced dose of biological therapy. The patients at low dose of biological therapy compared with standard dose, had similar mean disease duration, but received significantly less DMARDs, glucocorticoids and NSAIDs, and similar biological agent duration. RA patients with reduced biological treatment, at the time of analysis, had higher remission rates versus patients receiving a standard dose (82.9% vs 34%, p<0.0001). The medical decision at the time of analysis was to maintain low-dosage biological treatment in almost all patients.
In our clinical practice, 45.7% of our chronic arthritis patients receive low dose of biological therapy, after achieving remission or low activity at standard doses, maintaining a good control of the disease.