Effects of aspirin on vitreous/preretinal hemorrhage in patients with diabetes mellitus. Early Treatment Diabetic Retinopathy Study report no. 20.

OBJECTIVE: To assess whether the use of aspirin exacerbates the severity or duration of vitreous/preretinal hemorrhages in patients with diabetic retinopathy.

DESIGN: The Early Treatment Diabetic Retinopathy Study (ETDRS), a multicenter randomized clinical trial, was designed to assess the effect of photocoagulation and aspirin on 3711 patients with mild to severe nonproliferative or early proliferative diabetic retinopathy.

INTERVENTION: Patients were randomly assigned to either an aspirin (650 mg/d) or a placebo group. One eye of each patient was randomly assigned to early photocoagulation and the other to deferral of photocoagulation.

MAIN OUTCOME MEASURES: The severity and duration of the vitreous/preretinal hemorrhages were determined from gradings of the annual, seven standard stereoscopic field, fundus photographs. Clinical examinations scheduled every 4 months also provided information on the presence and duration of hemorrhages.

RESULTS: Annual fundus photographs of eyes assigned to deferral of photocoagulation revealed vitreous/preretinal hemorrhages at some time during follow-up in 564 patients (30%) assigned to the placebo group and 585 patients (32%) assigned to the aspirin group (P = .48). Based on gradings of fundus photographs, there were no statistical differences in the severity of vitreous/preretinal hemorrhages (P = .11) or their rate of resolution (P = .86) between the groups. Clinical examination of eyes assigned to deferral of photocoagulation revealed 721 eyes (39%) assigned to the aspirin group and 689 (37%) assigned to the placebo group that had vitreous/preretinal hemorrhages during the course of the study (P = .30). Again, no statistically significant difference was found between the rates of resolution, as assessed clinically, between the two treatment groups (P = .43).

CONCLUSIONS: As previously reported, the use of aspirin did not increase the occurrence of vitreous/preretinal hemorrhages in patients enrolled in the ETDRS. The data presented in this report demonstrate that the severity and duration of these hemorrhages were not significantly affected by the use of aspirin and that there were no ocular contraindications to its use (650 mg/d) in persons with diabetes who require it for treatment of cardiovascular disease or for other medical indications.