Abstract
BACKGROUND: This is the first cross-sectional study that aims to examine associations between beliefs about medication and non-adherence in patients with rheumatoid arthritis (RA) using disease-modifying antirheumatic drugs, taking potential psychological confounders into account. METHODS: Eligible patients (diagnosed with RA for >/=1 year or >/=18 years, using greater than or equal to one disease-modifying antirheumatic drug) were included by their rheumatologist during regular outpatient visits between September 2009 and September 2010. Included patients received questionnaires. The Beliefs about Medicines Questionnaire was used to measure the perceived need to take medication (necessity beliefs), the concerns about taking medication (concern beliefs), general medication beliefs, and attitudes toward taking medication. Medication non-adherence (no/yes) was measured using the Compliance Questionnaire Rheumatology (CQR). Associations between beliefs and non-adherence, and the influence of demographical, clinical, and psychological factors (symptoms of anxiety/depression, illness cognitions, self-efficacy) were assessed using logistic regression. RESULTS: A total of 580 of the 820 eligible patients willing to participate were included in the analyses (68% female, mean age 63 years, 30% non-adherent to their medication). Weaker necessity beliefs (OR [odds ratio]: 0.8, 95% CI [confidence interval]: 0.8-0.9) and an unfavorable balance between necessity and concern beliefs (OR: 0.9, 95% CI: 0.9-1.0) were associated with CQR non-adherence. Also, having an indifferent attitude toward medication (no/yes) was associated with CQR non-adherence (OR: 5.3, 95% CI: 1.1-25.8), but the prevalence of patients with an indifferent attitude toward medication was low. The associations were barely confounded by demographical, clinical, and psychological factors. CONCLUSION: Increasing necessity beliefs about medication in clinical practice might be worthwhile in improving medication adherence in RA patients.
