Background: For treating Rheumatoid Arthritis (RA) it’s clear that Treat to Target has presented the best strategy. The best outcome for patients has been attained by accepting clinical remission as the final objective in treatment. The development of new drugs for the treatment of RA has dramatically modified the approach clinicians have on the disease, however, the treatment of inflammatory conditions represents a challenge due to the multiple factors can affect its response.

It is known that non-adherence represents an increase in mortality, morbidity and healthcare costs.^1,2. Emphasis should be made on one of the most simple and effective variables that impact the effectiveness of treatment: adherence to treatment itself.

Objectives: This work aimed to evaluate the impact of methotrexate adherence on treatment outcome in patients with RA.

Methods: An observational, cross sectional study was performed using medical records from the Rheumatology Clinic at University Hospital from UANL Jose Eleuterio Gonzalez, Monterrey, México; the data was collected from 03/16/2018 to 01/29/2020. RA patients visits included fulfilled the 2010 ACR/EULAR classification, had their disease activity measured by Disease Activity Score 28 ESR (DAS28 ESR) and were treated with methotrexate as their primary disease modifying antirheumatic-drug (DMRAD). Patient disease activity was classified in 4 groups according to the DAS28 ESR score as <2.6 remission, 2.6-3.2 low activity, >3.2-5.1 moderate activity, >5.1 high activity.

Adherence to medication was evaluated utilizing a self-reported assessment that was applied per patient’s visit. Patients were classified into 4 groups according to the percentage of the prescribed doses of Methotrexate that they abided to. Statistical analysis was performed using IBM SPSS 21 statistical package. Descriptive analyses were performed with frequencies (%) and the correlation between the calculated disease activity versus patient adherence to treatment was calculated using Pearson correlation coefficient. P-values <0.05 were considered statistically significant.

Results: A total of 795 patients visits were included. They were 92.33% female, mean (SD) age was 52.44 (±12.99) (Table 1). The most frequent routes for methotrexate were Oral 603 (75.84%), Subcutaneous 113 (14.21%) and Intramuscular 79 (9.93%). A significant correlation r (795) =0.-183, (p<0.001) was found between Disease Activity according to DAS28 ESR and Adherence classification according to prescribed doses taken

Conclusion: Adherence to treatment with methotrexate therapy has a direct impact on RA treatment outcome. The evaluation of adherence to the prescribed treatment should be addressed before modifications in DMRAD therapy in patients with Rheumatoid Arthritis. Before considering treatment failure in a patient treated with methotrexate, adherence to treatment must be evaluated. According to our results, self-reported adherence appears to be a cost and time effective method to care for patients.

References: [1]Monchablon C, et. al. Assessment adherence to disease-modifying anti-rheumatic drugs in rheumatoid arthritis. Clinical Rheumatology. 2019;39(1):207-216.

[2]Scott DL, et al. (2010) Rheumatoid arthritis. Lancet 376:1094–1108.

Disclosure of Interests: None declared