Factores implicados en la adherencia terapeútica en la artritis reumatoideimpacto de la percepción del paciente

Abstract

Therapeutic adherence has become a topic of central interest for medical research. Rheumatoid Arthritis (RA) is a chronic systemic autoimmune disease that results in progressive irreversible joint damage and functional impairment. Studies have reported non-adherence rates of 20-50% in RA patients. Poor adherence has a negative impact on disease outcomes and implies an economic burden for the health system. Identifying the potential risk factors for nonadherence is essential to develope intervention strategies to solve this problem. The main object of this study is to establish the contribution of illness and medication beliefs to therapeutic adherence in RA. The secondary objectives are to find out the percentage of non-adherence in RA patients of the Hospital Central de la Defensa Gómez Ulla (HCDGU) and to explore the association of treatment adherence with other factors (patient demographics, disease characteristics and medication type). Adult patients diagnosed with RA in HCDGU were included in a crosssectional study. Compliance Questionnaire Rheumatology (CQR) was used to assess treatment adherence. Unsatisfactory compliance was defined as taking correct dosing < 80%. Illness and medication beliefs were evaluated using the “Brief Illness Perception Questionnaire “(IPQ-b) and the “Beliefs about medicine questionnaire” (BMQ). Demographic data and clinical characteristics were collected by standardized clinical interview and revision of medical records. The “Arthritis treatment satisfaction questionnaire “(ARTS) was used to estimate the degree of treatment satisfaction. One hundred forty four patients agreed to participate in the study, 106 (73.6%) women, with a mean age of 62 years (SD 12) and median disease duration of 5 years (interquartile range 25-75: 2-11). One hundred thirteen (78.4%) showed good treatment adherence. Strong beliefs about drugs potential damage was associated with poor compliance (13±5 vs. 11±3, p= 0.013), meanwhile increased belief in medication necessity was associated with good compliance (21±3 vs. 20±3, p= 0.015). From the illness perception measures, adherent patients had increased feeling of treatment control (8.8± 1.5 vs 7.7± 2.1,p= 0.008) and greater emotional response (6.2±3.1 vs 4.8±3.4,p= 0.042). A greater degree of satisfaction with treatment was observed among adherent patients (77.2±12.4 vs 69.9±12.5,p=0.004), with higher scores in the dimensions of efficacy (28.8±4.9 vs 26.3±6.1, p= 0.015) and convenience (12.9±2.1 vs 11.7±2.7, p=0.030) of the ARTS questionnaire. In a multivariate analysis was found that for each unit of increase in the score of BMQ´s damage domain, adherence was reduced by 20% (CI 95% 0.08-0.3, p= 0.001); for each unit of increase in treatment control item of the IPQ-b, adherence increased 1.4 times (CI 95% 1.1- 1.8,p= 0.006); and for each unit of increase in the emotional response item of the IPQ-b, adherence increased 1.3 times (CI 95% 1.1-1.5,p= 0.002). In conclusion, the percentage of adherence found was comparable to previously reported rates in RA patients. Illness and medication beliefs, as well as treatment satisfaction degree could influence compliance to treatment. More studies are needed in this field.