PLoS ONE (Jan 2012)

Adherence to interferon β-1b treatment in patients with multiple sclerosis in Spain.

  • Oscar Fernández,
  • Eduardo Agüera,
  • Guillermo Izquierdo,
  • Jorge Millán-Pascual,
  • Lluis Ramió I Torrentà,
  • Pedro Oliva,
  • Joaquin Argente,
  • Yasmina Berdei,
  • Jose Maria Soler,
  • Olga Carmona,
  • Jose Maria Errea,
  • Jordi Farrés,
  • Group on Adherence to IFNb-1b in Spain

DOI
https://doi.org/10.1371/journal.pone.0035600
Journal volume & issue
Vol. 7, no. 5
p. e35600

Abstract

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BackgroundAdherence to interferon β-1b (INFβ-1b) therapy is essential to maximize the beneficial effects of treatment in multiple sclerosis (MS). For that reason, the main objectives of this study are to assess adherence to INFβ-1b in patients suffering from MS in Spain, and to identify the factors responsible for adherence in routine clinical practice.Methodology/principal findingsThis was an observational, retrospective, cross-sectional study including 120 Spanish patients with MS under INFβ-1b treatment. Therapeutic adherence was assessed with Morisky-Green test and with the percentage of doses received. The proportion of adherent patients assessed by Morisky-Green test was 68.3%, being indicative of poor adherence. Nevertheless, the percentage of doses received, which was based on the number of injected medication, was 94.3%. The main reason for missing INFβ-1b injections was forgetting some of the administrations (64%). Therefore, interventions that diminish forgetfulness might have a positive effect in the proportion of adherent patients and in the percentage of doses received. In addition, age and comorbidities had a significant effect in the number of doses injected per month, and should be considered in the management of adherence in MS patients.Conclusion/significanceAmong all the available methods for assessing adherence, the overall consumption of the intended dose has to be considered when addressing adherence.