Evaluation of clinical and demographic characteristics in rheumatoid arthritis patients with a follow-up period of over ten years who initiated biological DMARD treatment at Hacettepe University rheumatology clinic

This study aims to examine the clinical and demographic characteristics of patients with Rheumatoid Arthritis (RA) who have the potential to receive biological drug treatment for over ten years and to identify factors associated with adherence to treatment during follow-up for more than ten years. The study included 640 RA patients who were followed between 2001 and 2022 at Hacettepe University, Department of Rheumatology. Retrospectively collected data were analyzed using appropriate statistical methods. Of all patients, 242 (37.8%) had a follow-up duration of over ten years, while 398 (66.7%) had less than ten years. Among the patients with a follow-up duration of over ten years, 197 were female (81.4%), and 218 (90.9%) were under bDMARD therapy at their last visit. 131 patients(54.1%) were admitted from Ankara, the capital city of Turkey.While 50.2% of the patients from Ankara had been followed for over ten years, only 29.8% of those from outside Ankara had been followed for the same duration (p<0.001).The average age of onset of symptoms for patients with a follow-up duration of over ten years was 36.9 ± 12.9 years, the average age at diagnosis was 38.7 ± 12.9 years, and the average duration between the onset of symptoms and the start of bDMARD treatment was 8.8 ± 6.9 years. Compared to patients with less than ten years of follow-up, patients with long-term follow-up had a longer time between the first symptom and initiation of bDMARD. Patients with treatment adherence had a higher prevalence of strong positive rheumatoid factor, higher frequency of being overweight,and a higher prevalence of metabolic syndrome components such as hypertension,diabetes, and hyperlipidemia. Treatment adherence was higher in patients with wellcontrolled acute phase response during long-term follow-up. Using synthetic DMARDs alongside bDMARDs did not significantly affect treatment adherence for over ten years. Long-term adherence was achieved when intravenous (i.v) treatment was used as the initial treatment option. While the patients' initial and follow-up activity values did not affect treatment continuity, patients with worse functional status were followed for a longer duration. At least 37.8% of the patients receiving bDMARD treatment have continued their follow-up at our center, while 34% continue to receive any bDMARD treatment. In conclusion, factors such as proximity of patients' place of residence to the hospital where they receive treatment, duration between the onset of symptoms and the start of bDMARD treatment, and pre-biological agent initiation CRP value appear to be important in terms of continued treatment follow-up for over ten years.