Background: Rheumatoid arthritis (RA) is the most common chronic immune inflammatory disease. The effectiveness of RA therapy largely depends on adherence to treatment. Non-compliance with the recommendations of the doctor leads to increased disease activity, a greater risk of complications and the increase in the cost of treatment.

Objectives: To determine predictors of adherence to treatment of patients with RA.

Methods: The study included 82 women with reliable RA according to the criteria of ACR1987 and / or EULAR / ACR2010 (mean age 53.3 ± 10.2 years, the age at the onset of the disease is 42.4 [36;51] years, mean duration of RA - 10.8 [6;14] years, DAS28 - 5.03 [4.3;5.8]). Treatment adherence was assessed according to the questionnaire “Quantitative Evaluation of Adherence to Treatment (KOP - 25)” [1]. The following indicators were calculated: adherence to drug therapy, adherence to medical support, adherence to lifestyle modification and their integral index. For all indicators, the level of values in the range up to 50% is interpreted as “low” («non-adherence to treatment»), from 51 to 75% - as “medium”, more than 75% - as “high”(«adherence to treatment»). The functional ability of patients was assessed by the Health Assessment Questionnaire (HAQ). The severity of pain was determined by VAS. Statistical processing was performing using the program STATISTICA 10.0.

Results: Adherence to drug therapy in women with RA was determined: low adherence in 32 (39%) patients, average in 34 (41.5%) patients and high in 16 (19.5%) patients; adherence to medical support: low in 26 (31.7%) patients, average in 40 (48.8%) patients, and high in 16 (19.5%) patients; adherence to lifestyle modification: low in 55 (67%) patients, average in 25 (30.5%) patients and high in 2 (2.5%) patients. According to the integral indicator of adherence to treatment, 34 (41.5%) patients were not adherent to treatment, average adherence was recorded in 42 (51.2%) patients, and high in 6 (7.3%) patients.

The HAQ functional impairment was absent in 7 (8.5%) patients, minimal impairment occurred in 26 (31.7%), moderate - in 40 (48.8%) and severe - in 9 (11%) patients.

Severe pain in the VAS was noted by 29 (35.4%) patients, moderate - 39 (47.6%), in 14 (17%) patients the pain syndrome was weakly expressed.

The relationships of adherence to treatment was established with age (r = -0.29, p <0.05), age at the onset of the disease (r = -0.28, p <0.05), HAQ index (r = -0.27, p <0.05), the number of swollen joints (r = -0.3, p <0.05).

Patients under age of 39 years were the most adherence to drug therapy.

In patients with medium and high adhering to treatment, the severity of pain according to VAS was significantly lower than in non-adherent patients (50.6 [34;66] and 60.4 [46;73], respectively, p = 0.04), In patients with treatment adherence, activity was significantly lower than in non-treatment adherents (DAS 28 (4.7 [3.5;5.4] and 5.3 [4.7;5.9], respectively, p = 0.04).

Conclusion: Low treatment adherence has 41,5% of RA patients. Predictors of adherence to treatment are the young age patients, the onset of the disease before age of 39 years. Non-treatment patients with RA have a higher activity of RA according to DAS28, pain intensity according to VAS, the worst functional status. To increase the effectiveness of treatment, constant interaction between the patient and the physician is necessary, explaining to patients the consequences of non-compliance with recommendations.

References: [1]Nikolaev N. A., Skirdenko Yu. P. Russian universal questionnaire for the quantitative evaluation of adherence to treatment (KOP - 25). Clinical pharmacology and therapy. 2018;27(1): 74-78.

Disclosure of Interests: None declared