Study sheds light on why many RA patients do not adhere to treatment

European League Against RheumatismJun 13 2016

Two new studies presented at the European League Against Rheumatism Annual Congress (EULAR 2016) have shed light on why so many patients with Rheumatoid Arthritis (RA) do not adhere to their therapy, even in the early stages of their treatment. These new insights should be used to inform strategies designed to improve treatment adherence that in turn will optimise treatment outcomes and reduce healthcare costs.

The two studies highlight that:

• Patients who experience autonomy through information seeking behaviour and have positive expectations about the course of their disease are much more likely to adhere to their treatment than those patients who feel less autonomous and become passive because of their joint pain
• Patient anxiety on starting methotrexate therapy predicts non-response to treatment at six months, and this might partly be explained by poor adherence.

To induce disease remission, patients with early RA should adhere to their disease-modifying antirheumatic drugs (DMARDs) in the first months after diagnosis. Non-adherence to DMARDs hampers the twin targets of RA treatment: obtaining low disease activity and decreasing radiological progression.

Adherence better in patients who seek treatment information and have positive expectations "Non-adherence has been shown to be a serious problem in the treatment of RA. The consequences of non-adherence not only affect RA patients' disease activity, but also the rheumatologist's treatment decisions, which may lead to higher health care costs," said lead author Dr Johanna Hazes from the Erasmus Medical Centre, Rotterdam, The Netherlands. "However, it remains unknown as to why so many RA patients do not adhere to their treatment."

To identify which early inflammatory arthritis patients are at risk for non-adherence in the first three months of treatment, a population of 259 adult patients, recently diagnosed with inflammatory arthritis and started on synthetic DMARDs, were interviewed to identify potential adherence predictors, and their adherence continuously measured using electronically monitored pill bottles.

Adherence started high, but rapidly declined over three months of follow-up. Out of 15 different factors that could potentially influence adherence, 'information seeking' and 'having positive expectations about their disease' were the only ones significantly associated with adherence. 'Adjusting to the pain' was associated with non-adherence.

Factors not associated with adherence included: depression; negative feelings; non-specific anxiety; disability; and responses to questions covering patients' perceptions of the necessity for their treatment and of any potential harm (including adverse effects) from their medication.

Anxiety on beginning methotrexate treatment thought to lead to poor adherence "Methotrexate is the DMARD of first choice in the treatment of RA; however, response to methotrexate is highly variable," said lead investigator Dr Suzan Verstappen of the Centre for Musculoskeletal Research, University of Manchester, UK. "Being able to predict which of our RA patients are likely to not respond would enable us to provide earlier access to alternative drugs with the hope of avoiding disease progression in some of our patients," she added.

Data on potential predictors of response to methotrexate were acquired at baseline via questionnaires, case notes and blood samples in a population of 781 adult RA patients. Non-response to treatment was defined as failing to fulfil EULAR criteria for a good response: disease activity score-28 (DAS28) at six months ?3.2, and reduction in DAS28 from baseline to six months >1.2.

"From a long list of lifestyle, clinical and psychosocial predictors at baseline, BMI, smoking and DAS28 score were each shown to significantly predict non-response six months after patients had started treatment with methotrexate. Of particular interest, however, is the role of participant anxiety on starting treatment with methotrexate in predicting response, which is likely to be the result of its negative effect on adherence," Dr Verstappen concluded.