Is omega-3 fatty acid protective against diabetic retinopathy?

Daily intake of omega-3 fatty acids (FA) 1 g appears to confer no clinically meaningful benefit on diabetic retinopathy (DR), reveals a study.

A team of investigators performed a subanalysis of ASCEND*, a double-blind, randomized, placebo-controlled trial of 1 g omega-3 FA (containing 460 mg eicosapentaenoic acid and 380 mg docosahexaenoic acid) daily for the primary prevention of serious cardiovascular events in 15,480 UK adults with diabetes (at least 40 years of age).

The investigators obtained linkage data using electronic National Health Service Diabetic Eye Screening Programme records in England and Wales and confirmed participant-reported eye events using medical record review. They also conducted intention-to-treat analyses of time until the main outcomes using log-rank and stratified log-rank methods.

Time to the first recording of referable disease (a composite of retinopathy or maculopathy based on the grading criteria defined by United Kingdom National Screening Committee) was the primary efficacy outcome. Other outcome measures included the referable disease outcome stratified by the severity of DR at baseline, any progression in retinopathy grade, and incident diabetic maculopathy.

Data for 7,360 participants (48 percent of those who were randomize din ASCEND) were analysed. Of these, 548 (14.8 percent) had a referable disease event in the omega-3 FA groups compared with 513 (13.9 percent) in the placebo group during a mean follow-up of 6.5 years (rate ratio, 1.07, 95 percent confidence interval, 0.95‒1.20; p=0.29).

No statistically significant differences were seen in the proportion of events for either of the other outcomes between the two groups.

*A Study of Cardiovascular Events iN Diabetes