title: The increased risk of ulcerative keratitis among disposable soft contact lens users.
abstract: Previous controlled studies on contact lens-associated ulcerative keratitis were performed before the widespread use of disposable contact lenses. Therefore, a controlled study was undertaken to determine the relative risk of ulcerative keratitis among users of disposable soft contact lenses compared with the risk among users of other lens types. Forty-six consecutive cases of contact lens-associated ulcerative keratitis were identified between January 1990 and June 1992 at a corneal specialty practice in western Michigan. Five controls, matched to each case patient according to the dispensing data and prescribing practitioner, were obtained for 42 cases (91%). Users of daily-wear rigid gas-permeable lenses had the lowest risk of developing ulcerative keratitis. Relative to users of daily-wear soft contact lenses, users of extended-wear soft contact lens had an age-adjusted and sex-adjusted relative risk of 1.87 (95% confidence interval, 0.61 to 5.71). Disposable soft contact lens users had the highest risk of developing ulcerative keratitis, with an adjusted relative risk of 14.16 (95% confidence interval, 5.47 to 37.63) compared with daily-wear soft contact lens users and 7.66 (95% confidence interval, 2.27 to 25.83) compared with conventional extended-wear soft contact lens users.
authors.affiliation: Dana Center for Preventive Ophthalmology, Johns Hopkins University, Baltimore, Md 21287-9012.
authors.forename: P O
authors.initials: PO
authors.lastname: Buehler
authors.forename: O D
authors.initials: OD
authors.lastname: Schein
authors.forename: J F
authors.initials: JF
authors.lastname: Stamler
authors.forename: D D
authors.initials: DD
authors.lastname: Verdier
authors.forename: J
authors.initials: J
authors.lastname: Katz
mesh_terms: D015823:Acanthamoeba Keratitis; D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D003263:Contact Lenses, Hydrophilic / Q000009:adverse effects*; D003320:Corneal Ulcer / Q000209:etiology* / Q000469:parasitology; D004209:Disposable Equipment; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors