title: Treatment Adherence in Type 1 Hereditary Tyrosinaemia (HT1): A Mixed-Method Investigation into the Beliefs, Attitudes and Behaviour of Adolescent Patients, Their Families and Their Health-Care Team.
abstract: BACKGROUND
  Type 1 hereditary tyrosinaemia (HT1) is a rare metabolic disorder caused by an enzymatic defect in the metabolism of the amino acid tyrosine. Primary treatment for HT1 is nitisinone (Orfadin) in conjunction with a low-tyrosine/phenylalanine diet. The appropriate use of nitisinone medication and adhering to specialist diet is thus central to the successful management of HT1.
  
  
  OBJECTIVE
  To date, no published research has examined adherence (to medication and diet) and factors that influence it in the context of HT1. This study aimed to ascertain the extent to which non-adherence is a problem in this patient population, identify perceived barriers and facilitators to treatment adherence and explore the role of illness beliefs and treatment perceptions in treatment management.
  
  
  METHODS
  The present study used a combination of qualitative interviews and quantitative survey methods with patients, carers and health-care professionals (HCPs).
  
  
  RESULTS
  This study found adherence to medication to be high amongst patients with HT1 and their carers who administer it. However, adherence to diet was reported to be much lower. A key factor influencing adherence to diet was age, with adolescents reported to have most difficulty adhering.
  
  
  CONCLUSIONS
  The results indicate that adherence to dietary instructions becomes more problematic as children with HT1 grow older. Greater involvement in managing their condition and in their consultation at an early stage may have a positive impact on future adherence by increasing their investment and understanding of the treatment regime, potentially making adherence rates more stable and less influenced by moving through different life stages.
authors.affiliation: Atlantis Healthcare, London, UK, Sumaira.Malik@atlantishealthcare.com.
authors.forename: Sumaira
authors.initials: S
authors.lastname: Malik
authors.forename: Sinead
authors.initials: S
authors.lastname: NiMhurchadha
authors.forename: Christina
authors.initials: C
authors.lastname: Jackson
authors.forename: Lina
authors.initials: L
authors.lastname: Eliasson
authors.forename: John
authors.initials: J
authors.lastname: Weinman
authors.forename: Sandrine
authors.initials: S
authors.lastname: Roche
authors.forename: John
authors.initials: J
authors.lastname: Walter