Importance: A recent study of ophthalmologic patients found a strong association between fluoroquinolone use and retinal detachment. Given the prevalent use of fluoroquinolones, this could, if confirmed in the general population, translate to many excess cases of retinal detachment that are potentially preventable.
Objective: To investigate if oral fluoroquinolone use is associated with an increased risk of retinal detachment.
Design, setting, and participants: A nationwide, register-based cohort study in Denmark from 1997 through 2011, using linked data on participant characteristics, filled prescriptions, and cases of retinal detachment with surgical treatment (scleral buckling, vitrectomy, or pneumatic retinopexy). The cohort included 748,792 episodes of fluoroquinolone use (660,572 [88%] ciprofloxacin) and 5,520,446 control episodes of nonuse.
Main outcomes and measures: Poisson regression was used to estimate rate ratios (RRs) for incident retinal detachment, adjusting for a propensity score that included a total of 21 variables. The risk windows were classified as current use (days 1-10 from start of treatment), recent use (days 11-30), past use (days 31-60), and distant use (days 61-180).
Results: A total of 566 cases of retinal detachment occurred, of which 465 (82%) were rhegmatogenous detachments; 72 in fluoroquinolone users and 494 in control nonusers. The crude incidence rate was 25.3 cases per 100,000 person-years in current users, 18.9 in recent users, 26.8 in past users, and 24.8 in distant users compared with 19.0 in nonusers. Compared with nonuse, fluoroquinolone use was not associated with a significantly increased risk of retinal detachment: the adjusted RRs were 1.29 (95% CI, 0.53 to 3.13) for current use; 0.97 (95% CI, 0.46 to 2.05) for recent use; 1.37 (95% CI, 0.80 to 2.35) for past use; and 1.27 (95% CI, 0.93 to 1.75) for distant use. The absolute risk difference, estimated as the adjusted number of retinal detachment cases per 1,000,000 treatment episodes, was 1.5 (95% CI, -2.4 to 11.1) for current use.
Conclusions and relevance: In this cohort study based on the general Danish population, oral fluoroquinolone use was not associated with increased risk of retinal detachment. Given its limited power, this study can only rule out more than a 3-fold increase in the relative risk associated with current fluoroquinolone use; however, any differences in absolute risk are likely to be of minor, if any, clinical significance.