Blue-blocking lenses do not relieve eye strain

Blue-blocking lenses are not necessarily better than standard clear lenses for individuals experiencing eye strain due to computer use, with a recent study reporting no marked improvements in signs or symptoms of eye strain.

The study randomly assigned 120 symptomatic computer users into a ‘positive’ or ‘negative’ advocacy arm (ie, a clinician either advocating, or not advocating, for the intervention via a prerecorded video). They were further sub-randomized to receive either clear (placebo) or blue-blocking spectacles. All participants were led to believe they had received an active intervention.

For assessments, the participants performed a 2-hour computer task while wearing their assigned spectacle intervention. The mean change (post- minus precomputer task) in eye strain symptom score and critical flicker-fusion frequency (CFF, an objective measure of eye strain) was measured as the primary outcome.

All participants completed the study. In the primary analysis, neither the type of lens nor clinician advocacy of the intervention altered the outcomes.

Specifically, CFF did not differ according to advocacy type (positive or negative; p=0.164) and spectacle intervention type (blue-blocking vs clear lens; p=0.304). The same was true for eye strain symptom score, where no marked differences were seen by advocacy (p=0.410) or spectacle lens types (p=0.394).

The intervention was safe, with no adverse events documented.