There is an association between depression and a person's circadian rhythm, but the relationship is complex. Essentially, sleep disruptions or changes in the sleep-wake cycle can lead to depression. But, depression can also cause disruptions to a person's sleep-wake cycle.
Fortunately, people who take medication to treat their depression or use bright light therapy may see improvements in both their mood and sleep health.
If you or a loved one lives with depression and have concerns about sleep health, it is important to talk with a health care provider who can help you explore treatment options.