Background Like in other chronic diseases, the adherence to disease-modifying treatments in multiple sclerosis (MS) is essential to maximise its efficacy. The adherence is relevant for the symptoms’ relief and delay in disease progression. It is essential to find out factors which could influence adherence rates in MS patients, in order to improve the management of the disease.

Purpose This study aims to evaluate the adherence to MS treatment in Spanish patients and find out variables that may influence it.

Material and methods Cross-sectional study conducted in MS Spanish patients receiving disease-modifying treatments≥1 year before the inclusion. The recruitment was performed in hospitals and patients’ associations by healthcare professionals and patient association’s staff. Adherence was measured using the Morisky–Green scale (four questions with dichotomous answers, compliance was considered with these answers: NO/YES/NO/NO) and related factors using a questionnaire addressing demographic/disease characteristics, global perception of pathology, impact of medication on patient life, administration route (oral/injectable/intravenous), treatment satisfaction and treatment decision-making. This questionnaire was elaborated and validated by an MS expert committee (hospital pharmacists, neurologist, patients’ associations: Fundación Esclerosis Múltiple Madrid (nurses) and Esclerosis Múltiple España (clinical psychologists).

Results One-hundred and fifty-seven MS patients (44 males/113 females) were included. The adherence rate was 71% (Morisky–Green scale), and was associated with: older age (mean: 45.2 years compliance; 40.4 years non-compliance), better cognitive status, being married/in-union, more lines of prior treatments, time to diagnosis of 5–10 years, exacerbations absence, clear information about the disease and high treatment satisfaction (table). There were no differences in the adherence rate between oral (63%) and injectable (77%) treatments. Analysing the injectable administration, there was greater adherence in patients with IV (100%) vs SC (68%). There was also a significant difference between IV (100%) vs oral (63%) (p=0.001). The main cause for non-compliance was forgetfulness (27%).

Conclusion Adherence rate for the MS treatment is acceptable (71%). It is negatively affected by forgetfulness, lower cognitive status and lack of family support. The injectable route shows higher adherence than the oral route, although the latter show the highest patient satisfaction.

References and/or acknowledgements Study supported by Roche, Spain. We gratefully acknowledge AMBER for its contribution (data collection/statistical analysis).

No conflict of interest.