title: Cysteamine (Cystagon®) adherence in patients with cystinosis in Spain: successful in children and a challenge in adolescents and adults.
abstract: BACKGROUND
  Cysteamine has improved survival and prognosis in cystinosis. Increasing numbers of patients reach adulthood and face new challenges such as compliance that wanes over time. The aim of this study was to evaluate adherence to cysteamine treatment in a group of cystinotic patients in Spain in an attempt to identify potential therapy pitfalls and improve the overall care of affected individuals. Despite the impact of cysteamine on prognosis, there is a paucity of data regarding adherence.
  
  
  METHODS
  Thirty-four cystinotic patients (21 male) 38% ≥18 years were enrolled in a voluntary, anonymous survey. Replies were obtained from patients (15/34), mothers (11/34), fathers (4/34) and both parents (4/34).
  
  
  RESULTS
  Patient age (median and interquartile range) at diagnosis was 1 year (0.57-1), and patient age at Cystagon® initiation was also 1 year (0.8-1.8). Sixteen (47%) were kidney transplant (KTx) recipients; six were retransplanted. Age at first KTx 10 years (8.7-13.7). Patient understanding of multiorgan involvement in cystinosis: 4.1 organs reported; eye 97% and kidney 91%. Cysteamine was given by mother (100%) and father (83%) in <11 year olds, or self-administered (94%) in ≥11 year olds. Four daily doses in 89% versus 56% in <11 year olds or ≥11 year olds, with fixed schedule in 94% versus 50% in <11 or ≥11 year olds and progressive loss of reminders over time. Furthermore, 44% complained of unpleasant smell. Motivation for treatment compliance was 100% versus 40% in <11 versus ≥11 year olds, respectively. Disease impact in patients <18 years is as follows: school (29%), social (14%), 'feeling different' (10%); in patients ≥18 years: 'feeling different' (62%), professional (39%) and job absenteeism (31%). Referring physician: paediatric nephrologist (94%) and nephrologist (63%) in <11 versus ≥11 year olds. Ophthalmological follow-up: 83% versus 38% in <11 versus ≥11 year olds. Patient opinion of physician expertise: paediatric nephrologist (94%) and nephrologist (44%). New treatment options (65%) and better information (42%) were demanded to improve adherence.
  
  
  CONCLUSIONS
  Treatment with Cystagon is effective in young patients. However, adherence diminishes over time in adolescents and adults despite disease impact. Strategies such as better information on the disease, patient self-care promotion and facilitated transition to adult healthcare services are required to improve compliance and the clinical management of cystinosis.
authors.affiliation: Hospital Universitari Vall d' Hebron, Barcelona, Spain Hospital Universitario Cruces, Bilbao, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Ariceta
authors.affiliation: Hospital Universitari Vall d' Hebron, Barcelona, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Lara
authors.affiliation: Hospital Sant Joan de Déu, Barcelona, Spain.
authors.forename: Juan A
authors.initials: JA
authors.lastname: Camacho
authors.affiliation: Hospital Universitari Clínic, Barcelona, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Oppenheimer
authors.affiliation: Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Vara
authors.affiliation: Hospital Universitario Central de Asturias y Universidad de Oviedo, Oviedo, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Santos
authors.affiliation: Hospital Universitario Virgen de la Salud, Toledo, Spain.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Muñoz
authors.affiliation: Hospital Universitari Vall d' Hebron, Barcelona, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Cantarell
authors.affiliation: Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Gil Calvo
authors.affiliation: Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Romero
authors.affiliation: Hospital Universitario Materno-Infantil Las Palmas, Las Palmas de Gran Canaria, Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: Valenciano
authors.affiliation: Hospital Universitario Ntra. Sra. de la Candelaria, Santa Cruz de Tenerife, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: García-Nieto
authors.affiliation: Hospital Universitario La Fe, Valencia, Spain.
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Sanahuja
authors.affiliation: Hospital Universitario Dr Peset, Valencia, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Crespo
authors.affiliation: Hospital Universitario Miguel Servet, Zaragoza, Spain.
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Justa
authors.affiliation: Hospital Arquitecto Marcide, Ferrol, Spain.
authors.forename: Adela
authors.initials: A
authors.lastname: Urisarri
authors.affiliation: Hospital Universitario Virgen del Rocío, Sevilla, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Bedoya
authors.affiliation: Hospital Universitario Materno-Infantil, Materno-Infantil Carlos Haya, Málaga, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bueno
authors.affiliation: Complejo Hospitalario de Torrecárdenas, Almería, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Daza
authors.affiliation: Hospital Universitario Virgen de Las Nieves, Granada, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Bravo
authors.affiliation: Hospital General de Albacete, Albacete, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Llamas
authors.affiliation: Hospital General Universitario de Alicante, Alicante, Spain.
authors.forename: Luis Antonio
authors.initials: LA
authors.lastname: Jiménez Del Cerro
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003543:Cysteamine / Q000627:therapeutic use*; D065104:Cystine Depleting Agents / Q000627:therapeutic use*; D003554:Cystinosis / Q000188:drug therapy*; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D055118:Medication Adherence; D011379:Prognosis; D012648:Self Care; D013030:Spain; D055815:Young Adult
chemical_list: D065104:Cystine Depleting Agents; D003543:Cysteamine
keywords: adherence; cysteamine; cystinosis; prognosis; transition