title: Treatment persistence in patients with rheumatoid arthritis and ankylosing spondylitis.
abstract: OBJECTIVE
  To evaluate treatment persistence in patients with rheumatoid arthritis and ankylosing spondylitis who started therapies with disease-modifying antirheumatic drugs (DMARD) and tumor necrosis factor blockers (anti-TNF drugs).
  
  
  METHODS
  This retrospective cohort study from July 2008 to September 2013 evaluated therapy persistence, which is defined as the period between the start of treatment until it is discontinued, allowing for an interval of up to 30 days between the prescription end and the start of the next prescription. Odds ratio (OR) with 95% confidence intervals (95%CI) were calculated by logistic regression models to estimate the patients' chances of persisting in their therapies after the first and after the two first years of follow-up.
  
  
  RESULTS
  The study included 11,642 patients with rheumatoid arthritis - 2,241 of these started on anti-TNF drugs (+/-DMARD) and 9,401 patients started on DMARD - and 1,251 patients with ankylosing spondylitis - 976 of them were started on anti-TNF drugs (+/-DMARD) and 275 were started on DMARD. In the first year of follow-up, 63.5% of the patients persisted in their therapies with anti-TNF drugs (+/-DMARD) and 54.1% remained using DMARD in the group with rheumatoid arthritis. In regards to ankylosing spondylitis, 79.0% of the subjects in anti-TNF (+/-DMARD) group and 41.1% of the subjects in the DMARD group persisted with their treatments. The OR (95%CI) for therapy persistence was 1.50 (1.34-1.67) for the anti-TNF (+/-DMARD) group as compared with the DMARD group in the first year for the patients with rheumatoid arthritis, and 2.33 (1.74-3.11) for the patients with ankylosing spondylitis. A similar trend was observed at the end of the second year.
  
  
  CONCLUSIONS
  A general trend of higher rates of therapy persistence with anti-TNF drugs (+/-DMARD) was observed as compared to DMARD in the study period. We observed higher persistence rates for anti-TNF drugs (+/-DMARD) in patients with ankylosing spondylitis as compared to rheumatoid arthritis; and a higher persistence for DMARD in patients with rheumatoid arthritis as compared to ankylosing spondylitis.
  
  
  OBJECTIVE
  Avaliar a persistência do tratamento em pacientes com artrite reumatoide e espondilite anquilosante que iniciaram terapia com medicamentos modificadores do curso da doença (MMCD) e agentes bloqueadores do fator de necrose tumoral (anti-TNF).
  Este estudo de coorte retrospectiva de julho de 2008 a setembro de 2013 avaliou a persistência na terapia, definida como o tempo do início até a descontinuação, permitindo-se um intervalo de até 30 dias entre o fim da prescrição e o início da prescrição seguinte. Odds ratio (OR) com intervalos de confiança de 95% (IC95%) foram calculados por meio de modelos de regressão logística para estimar a chance de apresentar persistência na terapia após o primeiro e os dois primeiros anos de seguimento.
  
  
  RESULTS
  Foram incluídos 11.642 pacientes com artrite reumatoide - 2.241 iniciaram uso de agentes anti-TNF (+/-MMCD) e 9.401 iniciaram MMCD - e 1.251 pacientes com espondilite anquilosante - 976 iniciaram uso de agentes anti-TNF (+/-MMCD) e 275 iniciaram MMCD. No primeiro ano de acompanhamento, 63,5% persistiram em terapia com anti-TNF (+/-MMCD) e 54,1% em uso de MMCD do grupo com artrite reumatoide. Em relação à espondilite anquilosante, 79,0% do grupo anti-TNF (+/-MMCD) e 41,1% do grupo MMCD persistiram no tratamento. O OR (IC95%) para persistência na terapia foi de 1,50 (1,34-1,67) para o grupo anti-TNF (+/-MMCD) comparado com MMCD no primeiro ano em pacientes com artrite reumatoide, e de 2,33 (1,74-3,11) em pacientes com espondilite anquilosante. Foi observada tendência semelhante ao final do segundo ano.
  Observou-se uma tendência geral de taxas mais elevadas de persistência na terapia com anti-TNF (+/-MMCD) em relação a MMCD no período estudado. Foram observadas taxas de persistência mais elevadas para os usuários de anti-TNF (+/-MMCD) em pacientes com espondilite anquilosante em relação a artrite reumatoide, e maior persistência para MMCD em pacientes com artrite reumatoide em relação à espondilite anquilosante.
authors.affiliation: Programa de Pós-Graduação em Saúde Pública. Faculdade de Medicina. Universidade Federal de Minas Gerais. Belo Horizonte, MG, Brasil.|Research Institute of the McGill University Health Centre. Montreal, Quebec, Canada.
authors.forename: Marina Amaral de Ávila
authors.initials: MA
authors.lastname: Machado
authors.affiliation: Division of Clinical Epidemiology. McGill University. Montreal, Quebec, Canada.
authors.forename: Cristiano Soares de
authors.initials: CS
authors.lastname: Moura
authors.affiliation: Programa de Pós-Graduação em Saúde Pública. Faculdade de Medicina. Universidade Federal de Minas Gerais. Belo Horizonte, MG, Brasil.
authors.forename: Felipe
authors.initials: F
authors.lastname: Ferré
authors.affiliation: Research Institute of the McGill University Health Centre. Montreal, Quebec, Canada.|Division of Clinical Epidemiology. McGill University. Montreal, Quebec, Canada.
authors.forename: Sasha
authors.initials: S
authors.lastname: Bernatsky
authors.affiliation: Research Institute of the McGill University Health Centre. Montreal, Quebec, Canada.|Division of Clinical Epidemiology. McGill University. Montreal, Quebec, Canada.
authors.forename: Elham
authors.initials: E
authors.lastname: Rahme
authors.affiliation: Research Institute of the McGill University Health Centre. Montreal, Quebec, Canada.|Departamento de Farmácia Social. Faculdade de Farmácia. Universidade Federal de Minas Gerais. Belo Horizonte, MG, Brasil.
authors.forename: Francisco de Assis
authors.initials: Fde A
authors.lastname: Acurcio
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D001691:Biological Therapy; D001938:Brazil; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000627:therapeutic use*
chemical_list: D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha