Argon Laser Photocoagulation and Aspirin Treatment for Diabetic Retinopathy Management
Aspirin
+ Argon Laser Photocoagulation
Cardiovascular Diseases+13
+ Diabetes Mellitus
+ Diabetic Angiopathies
Treatment Study
Summary
Study start date: December 1, 1979
Actual date on which the first participant was enrolled.ETDRS was a multicenter, randomized clinical trial designed to evaluate argon laser photocoagulation and aspirin treatment in the management of patients with nonproliferative or early proliferative diabetic retinopathy. A total of 3,711 patients were recruited to be followed for a minimum of 4 years to provide long-term information on the risks and benefits of the treatments under study. The eligibility criteria for the ETDRS were designed to include a broad range of macular edema severity, from a few small hard exudates within a disc diameter of the fovea with normal visual acuity to extensive cystoid spaces with a visual acuity of 20/200. All study patients had one eye randomly assigned to immediate photocoagulation and the other eye to deferral of photocoagulation until high-risk proliferative retinopathy developed. During followup, additional photocoagulation was allowed for any degree of macular edema within the eligibility range, but additional photocoagulation was required only for edema involving or threatening the center of the macula. The term "clinically significant macular edema" was coined to designate this level of severity. The trial use of aspirin therapy was based on clinical observation and on aspirin's possible mechanisms of action. Previous observations of diabetic patients who were taking large doses of aspirin for rheumatoid arthritis showed that the prevalence of retinopathy in this group was lower than the prevalence that would be expected in the diabetic population at large. Evidence suggested that diabetic patients have altered platelet aggregation and disaggregation, which may contribute to the capillary closure seen in retinopathy. This abnormality is reversed by aspirin in vitro . However, because of aspirin's other possible mechanisms of action and its well-known side effects, such as allergic, idiosyncratic, and intolerance reactions, the use of this therapy in the ETDRS was carefully controlled and monitored.
Protocol
This section provides details of the study plan, including how the study is designed and what the study is measuring.Treatment Study
Eligibility
Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.Any sex
Biological sex of participants that are eligible to enroll.From 18 to 70 Years
Range of ages for which participants are eligible to join.Healthy volunteers not allowed
If individuals who are healthy and do not have the condition being studied can participate.Conditions
Pathology
Criteria
Men and women between the ages of 18 and 70 years with moderate or severe nonproliferative diabetic retinopathy or mild proliferative retinopathy in both eyes, with no previous photocoagulation treatment, and with visual acuity of 20/40 or better (20/200 or better if macular edema is present) were eligible for this study.