title: The incidence of irreversible retinal toxicity in patients treated with hydroxychloroquine: a reappraisal.
abstract: OBJECTIVE
  To define the risk of hydroxychloroquine (HCQ)-related retinal toxicity in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) who are receiving recommended dosages of the drug (< or =6.5 mg/kg/day).
  
  
  METHODS
  Prospective cohort study, from 1985 to 2000.
  
  
  METHODS
  Greek patients with RA (n = 335) and SLE (n = 191) treated with HCQ, 400 of whom had completed at least 6 years of treatment.
  
  
  METHODS
  Ophthalmologic evaluation was performed every 6 months from 1985 to 1995, and yearly thereafter. This consisted of best-corrected visual acuity, color vision testing, static central visual field testing, fundoscopy, electroretinography, and fluorescein angiography, when indicated.
  
  
  METHODS
  Fundus lesions attributed to HCQ.
  
  
  RESULTS
  No HCQ retinal toxicity was noted in any of the 526 patients during the first 6 years of treatment. Two (3.4%) of the first 58 long-term (>6 years) treated patients developed HCQ-related maculopathy at 8 and 6.5 years of treatment, despite regular ophthalmologic evaluation. On follow-up 7 and 9 years after cessation of HCQ treatment, both patients had stable eye disease. No HCQ retinal toxicity was observed in the subsequent 342 patients who were treated for >6 years. Overall, the incidence of HCQ-related retinopathy in 400 patients who were treated with recommended dosages of the drug for a mean of 8.7 years was reduced to 0.5%.
  
  
  CONCLUSIONS
  After a baseline ophthalmic examination to confirm the absence of preexisting fundus pathology, patients with normal renal function may receive HCQ at a maximal daily dosage of 6.5 mg/kg and continue safely for 6 years. However, annual screening is recommended in patients who have taken the drug, even in recommended doses, for >6 years.
authors.affiliation: Department of Ophthalmology, Athens Eye Hospital, Athens, Greece. jmavrikakis@yahoo.com
authors.forename: Ioannis
authors.initials: I
authors.lastname: Mavrikakis
authors.forename: Petros P
authors.initials: PP
authors.lastname: Sfikakis
authors.forename: Emmanouil
authors.initials: E
authors.lastname: Mavrikakis
authors.forename: Kostantinos
authors.initials: K
authors.lastname: Rougas
authors.forename: Athanasios
authors.initials: A
authors.lastname: Nikolaou
authors.forename: Charalambos
authors.initials: C
authors.lastname: Kostopoulos
authors.forename: Myron
authors.initials: M
authors.lastname: Mavrikakis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D015331:Cohort Studies; D003118:Color Perception; D004596:Electroretinography; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D006115:Greece / Q000453:epidemiology; D006801:Humans; D006886:Hydroxychloroquine / Q000009:adverse effects / Q000627:therapeutic use*; D015994:Incidence; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012160:Retina / Q000187:drug effects / Q000473:pathology; D012164:Retinal Diseases / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology*; D012307:Risk Factors; D014787:Vision Tests; D014792:Visual Acuity; D014794:Visual Fields
chemical_list: D018501:Antirheumatic Agents; D006886:Hydroxychloroquine