Risk factors and complications of subconjunctival hemorrhages in patients taking warfarin.

Objectives: The aim of this study was to identify patients with subconjunctival hemorrhage (SCH) on warfarin therapy, to describe risk factors that may contribute to SCH development, and to identify complications related to SCH.

Methods: A retrospective chart review was conducted including patients treated at a university anticoagulation clinic over 2 years (4,334 patient visits). Data collection included patient demographics; international normalized ratios (INRs) before, at time of, and after SCH; risk factors for increased risk of bleeding; patient-reported complications related to SCH; recent changes in medication use; and warfarin dosage adjustments made in response to the event. The data were summarized using descriptive statistics and frequencies described as percentages.

Results: Fifteen SCH events were identified at an event rate of 0.35%. Two were excluded because of related surgeries near the time of SCH events. The average patient age was 67.3 years (range, 51 to 82). A total of 76.9% (n = 10) of patients had INRs within the goal range at the appointment before reporting the SCH. A total of 46.2% (n = 6) of patients reported alterations in medication regimens during the month preceding SCH. Various patient conditions were documented that may increase the risk of SCH development. No ophthalmic complications were associated with SCHs.

Conclusions: An SCH event rate of 0.35% was identified. Many factors may have precipitated SCH; however, ophthalmic complications were uncommon.