Recurrence of retinal vein thrombosis with Pycnogenol® or Aspirin® supplementation: a registry study

The aim of this study was to use Pycnogenol® to reduce the recurrence of retinal vein thrombosis (RVT) after a first episode. Pycnogenol® is an anti-inflammatory, anti-edema and an antiplatelet agent with a "mild" antithrombotic activity. The registry, using Pycnogenol® was aimed at reducing the number of repeated episodes of RVT.

Possible management options--chosen by patients--were: standard management; standard management + oral Aspirin® 100 mg once/day (if there were no tolerability problems before admission); standard management + Pycnogenol® two 50 mg capsules per day (for a total of 100 mg/day). Number of subjects, age, sex, distribution, percentage of smokers, and vision were comparable.

Recurrent RVT was seen in 17.39% of controls and in 3.56% of subjects supplemented with Pycnogenol® (P<0.05 vs. controls). There was RVT in 15.38% of the subjects using Aspirin®. The incidence of RVT was 4.88 times higher with standard management in comparison with the supplement group and 4.32 lower with Pycnogenol® supplementation in comparison with Aspirin®. Vision level was better with Pycnogenol® (20/25 at nine months; P<0.05). With Pycnogenol®, edema at the retinal level was also significantly reduced compared to the other groups. Pycnogenol® has a very good safety profile. In the Aspirin® group 26 completed 9 months and 6 subjects dropped out for tolerability problems. In the Aspirin® group, 2 minor, subclinical, retinal, hemorrhagic episodes during the follow-up were observed (2 subjects out of 26, equivalent to 7.69%). This pilot registry indicates that Pycnogenol® seems to reduce the recurrence of RVT without side effects. It does not induce new hemorrhagic episodes that may be theoretically linked to the use of Aspirin® (or other antiplatelets).

Larger studies should be planned involving a wider range of conditions, diseases and risk factors associated to RVT and to its recurrence.