title: Long-term use of antimalarial drugs in rheumatic diseases.
abstract: OBJECTIVE
  To evaluate long-term use of antimalarial drugs and to analyse all causes of discontinuation.
  
  
  METHODS
  This is a retrospective study of a cohort of rheumatic diseases patients on antimalarials, during a maximum period of 17.5 years. Case was defined as antimalarial treatment discontinuation due to: a) lack of efficacy, b) adverse events, and c) other causes. Survival techniques were used to estimate the incidence rate (IR) per 1,000 patient-years with the 95% Confidence Interval (95% CI) of antimalarial treatment discontinuation. Cox regression models were conducted to evaluate possible associated factors to antimalarial discontinuation.
  
  
  RESULTS
  One thousand, two hundred and ninety-one medical records were reviewed, and 778 patients were included. Patients started 869 different courses of treatment, with a total follow-up of 2,263 person-years. The IR of global discontinuation was 204 (95% CI 186-224). Fifty-two per cent of the treatments stopped were related to adverse events, 14% to lack of efficacy; and 34% to other reasons (refusal to take medication, ocular comorbidity, remission, or pregnancy). Adverse events discontinuations were related to non-ophthalmologic reasons in 54.5% (gastrointestinal, neuro-psychiatric, skin problems), and to ophthalmologic adverse events in 45.5%. Nine patients suffered definite presence of antimalarial retinopathy (IR: 3.97 [IC 95%: 2.06-7.62]) and one of them irreversible loss of vision (IR: 0.44 [IC 95%: 0.06-3.12]). Women, increasing age, and chloroquine vs. hydroxychloroquine use, increased the risk of discontinuation due to ophthalmologic adverse events.
  
  
  CONCLUSIONS
  Results suggest that antimalarials have a good balance between benefit and risk. However, we noted a number of discontinuations due to both inefficacy and adverse events. The potential for an unusual but serious ophthalmologic toxicity emphasises the importance of close ophthalmologic monitoring.
authors.affiliation: Rheumatology Unit, Hospital Clinico San Carlos, Madrid, Spain. jjover.hcsc@salud.madrid.org
authors.forename: J A
authors.initials: JA
authors.lastname: Jover
authors.forename: L
authors.initials: L
authors.lastname: Leon
authors.forename: E
authors.initials: E
authors.lastname: Pato
authors.forename: E
authors.initials: E
authors.lastname: Loza
authors.forename: Z
authors.initials: Z
authors.lastname: Rosales
authors.forename: M A
authors.initials: MA
authors.lastname: Matias
authors.forename: R
authors.initials: R
authors.lastname: Mendez-Fernandez
authors.forename: D
authors.initials: D
authors.lastname: Díaz-Valle
authors.forename: J M
authors.initials: JM
authors.lastname: Benitez-Del-Castillo
authors.forename: L
authors.initials: L
authors.lastname: Abasolo
mesh_terms: D000328:Adult; D000368:Aged; D000962:Antimalarials / Q000008:administration & dosage* / Q000009:adverse effects; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D002738:Chloroquine / Q000008:administration & dosage* / Q000009:adverse effects; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006886:Hydroxychloroquine / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012216:Rheumatic Diseases / Q000188:drug therapy* / Q000453:epidemiology; D012307:Risk Factors; D013995:Time
chemical_list: D000962:Antimalarials; D018501:Antirheumatic Agents; D006886:Hydroxychloroquine; D002738:Chloroquine