AB0423 CHANGES IN DISEASE ACTIVITY, PAIN, GLOBAL HEALTH AND PHYSICAL FUNCTION AFTER SWITCHING FROM ORAL TO SUBCUTANEOUS METHOTREXATE: RESULTS OF THE SIX-MONTH OBSERVATIONAL PROSPECTIVE STUDY IN CROATIA

Background:

In rheumatoid arthritis (RA) and psoriatic arthritis (PsA) methotrexate (MTX) is usually the first choice in the treatment strategy. Bioavailability of oral MTX reaches plateau in doses ≥15 mg weekly, and this is the reason of its lower clinical efficacy.

Objectives:

The objective of this observational longitudinal study was to evaluate the changes in disease activity, intensity of pain, global health, and physical function when switching from oral (P.O.) to subcutaneous (S.C.) MTX in patients with RA and peripheral form of PsA.

Methods:

Forty-eight consecutive patients (79.2% women) with established diagnosis of RA (77.1%) and peripheral PsA were enrolled from the outpatient clinics in six centres in Croatia. Median age was 61 (39-79) years, and the median of disease duration was 120 (3-528) months. Data were collected at baseline (T0) including retrospective data collection from the previous 3 months (on P.O. MTX), at day 90 (±10 days) (T1) and at day 180 (±10 days) (T2) for the previous periods, both of them during S.C. MTX treatment. Dose of MTX remained stable during the study. Domains of interest were Disease Activity Score on 28 joints measured using ESR (DAS28-ESR), level of pain, Patent's Global Health Assessment (PtGHA) and Physician's Global Health Assessment (PhGHA) were measured on horizontal 100 mm VAS, while physical function was measured by Health Assessment Questionnaire – Disability Index (HAQ-DI).

Results:

Out of 48 patients 41 patients were switched to S.C. MTX monotherapy and 7 to S.C. MTX in combination with another csDMARD. At T1 40 patients were on S.C. MTX monotherapy and 8 on S.C. MTX in combination with another DMARD, and at T2 39 patients were on S.C. MTX monotherapy, 4 on S.C. MTX in combination with another DMARD, 1 on another DMARD and 4 were lost to follow-up. DAS28 showed trend of decrease from 4.9 at baseline to 4.6 at T1 and 4.2 at T2. Analysis of transition of patients according to DAS28 EULAR criteria has shown that percentage of patients with low disease activity has raised from 4.3% at T0, to 21.7% at T1, and 24.3% at T2, while percentage of patients with high disease activity has declined from 38.3% at T0 to 21.7% at T1 and 13.5% at T2. Recommendation for prednisone therapy > 7.5 mg/QD had 12.5% patients at T0 and T1, and only 6.8% patients at T2. There was a significant decrease in adjusted mean values for level of pain (-1.46; 95%CI -1.55, -0.35), PtGHA (-1.12; 95%CI -1.50, -0.73) and PhGHA (-1.15; 95%CI -1.50, -0.80). HAQ-DI showed significant improvement during the 6-month follow-up (-0.25; 95%CI -0.32, -0.17).

Conclusion:

Patients who switched from P.O. to S.C. MTX showed improvement in all observed parameters: decrease of disease activity, reduction of pain, better global health, and physical function. Results of our study are in line with previously published literature data.

Disclosure of Interests:

None declared