Blocking bedtime blues Original paper

People with bipolar disorder often suffer from sleep disturbances, which have a negative effect on mood. Given the role blue light plays in regulating sleep-wake cycles, blue-blocking glasses may improve sleep in bipolar patients.

For this 2-week randomized controlled trial, 43 bipolar patients with insomnia wore either blue-blocking glasses or placebo glasses from 8 p.m. to bedtime. Sleep quality and circadian rhythm patterns were measured at the start and end of the study.

Although sleep quality did not appear to differ between groups, the group wearing blue-blocking glasses shifted to an earlier bedtime — an important finding, considering that later bedtimes are associated with increased depression among bipolar patients.

Despite randomization, the group wearing blue-blocking glasses had a higher use of antidepressants (which are known to interfere with sleep quality in some people).