UV-filtering intraocular lenses provide slight sleep benefit

Ultraviolet-filtering (UVF) intraocular lenses (IOLs) seem to have a more beneficial effect on sleep than blue-light-filtering (BF) IOLs, a recent meta-analysis has found. Nevertheless, evidence for this effect remains weak; further studies are needed before strong recommendations can be made.

Drawing from the databases of PubMed, Embase, and the Cochrane Library, the researchers retrieved four randomized controlled trials, two cohort studies, and one nonrandomized trial, all eligible for analysis. All studies identified compared the impacts of the two IOL types on subjective sleep quality, though only six had statistical data available for the meta-analysis.

Fixed-effect models showed that subjective sleep quality improved to a significantly greater degree in patients who had received the UVF-IOL implants compared to their BF counterparts 3–8 weeks after the procedure (standardized mean difference [SMD], 0.10, 95 percent confidence interval [CI], 0.00–0.21).

Such an effect was short-lived, however, and statistical significance was attenuated 7–12 months after the implantation (SMD, 0.03, 95 percent CI, –0.08 to 0.13).

Random effects model revealed a similar beneficial effect of UVF-IOL over BF-IOL at 3–8 weeks but failed to reach significance (SMD, 0.16, 95 percent CI, –0.07 to 0.39). No between-group difference was detected by 7–12 months (SMD, 0.03, 95 percent CI, –0.08 to 0.13).

“[O]ur findings provide some insights into the effects of short wavelength electromagnetic radiation on the circadian rhythm. Additional trials and studies with larger sample sizes are warranted to clarify this issue,” the researchers said.