Despite identifying 34 trials related to treatments for blepharitis, there is no strong evidence for any of the treatments in terms of curing chronic blepharitis. Commercial products are marketed to consumers and prescribed to patients without substantial evidence of effectiveness. Further research is needed to evaluate the effectiveness of such treatments. Any RCT designed for this purpose should separate participants by type of condition (e.g. staphylococcal blepharitis or MGD) in order to minimize imbalances between groups (type I errors) and to achieve statistical power for analyses (prevent type II errors). Medical interventions and commercial products should be compared with conventional lid hygiene measures, such as warm compresses and eyelid margin washing, to determine effectiveness, as well as head-to-head to show comparative effectiveness between treatments. Outcomes of interest should be patient-centered and measured using validated questionnaires or scales. It is important that participants be followed long-term, at least one year, to assess chronic outcomes properly.
The role of omega-3 dietary supplementation in blepharitis and meibomian gland dysfunction (an AOS thesis).
Blepharitis and meibomian gland dysfunction (MGD) are common sources of complaints from patients. To evaluate the effect on ocular symptoms, ocular findings, and serum and meibomian gland contents, patients with blepharitis and MGD were prospectively evaluated to determine the effects of dietary supplementation with omega-3 fatty acids.
                In a prospective randomized placebo-controlled masked trial, patients with simple obstructive MGD and blepharitis, who had discontinued all topical medications and tetracyclines, received oral omega-3 dietary supplementation consisting of two 1000-mg capsules 3 times a day. Patients were examined every 3 months for 1 year with the Ocular Surface Disease Index (OSDI) objective clinical measures, including tear production and stability, ocular surface and meibomian gland health, and biochemical plasma, red blood cell (RBC), and meibum evaluation. Primary outcome measures were change in tear breakup time (TBUT), meibum score, and overall OSDI score at 1 year.
                At 1 year, the omega-3 group had a 36% and 31% reduction in their omega-6 to omega-3 fatty acid ratios in RBCs and plasma, respectively (P = .3), whereas the placebo group demonstrated no change. At 12 months, the omega-3 group had an improvement in TBUT, OSDI score, and meibum score. Changes in meibum content were observed in the omega-3 group (P = .21); the level of meibum saturated fatty acids decreased.
                This trial demonstrated a decrease in the RBC and plasma ratios of omega-6 to omega-3 in patients taking omega-3 dietary supplementation, as compared to controls, and improvements in their overall OSDI score, TBUT, and meibum score. This is the first demonstration of an induced change in the fatty acid saturation content in meibum as a result of dietary supplementation with omega-3 fatty acids.