The relationship between disrupted sleep and mood disorders

Research Summary
Hayley Roper
Research Assistant

A large study, published this month in The Lancet Psychiatry shows that disruptions to our 24-hour sleep-wake cycle are associated with an increased risk of mood disorders.

In this study, 91,000 UK residents ages 37-93 wore activity trackers on their wrists for 7 days. From these data, researchers could estimate when participants were awake and asleep within a 24-hour period. Participants reported on their mood, mental health, and well-being. The researchers also collected information that might influence mental health such as alcohol intake, level of education, smoking status, body-mass index, and childhood trauma. These data were collected between 2013 and 2015.

The researchers found that individuals who were more active during sleep hours and/or less active during wake hours were at an increased risk of mood disorders, including depression and bipolar disorder. The researchers report that this finding could not be explained by other factors such as education, smoking, drinking, and childhood trauma.

These results are correlational. This means that it is unclear how disruptions to the sleep-wake cycle relate to mood disorders.

It is possible that chronic sleep disturbances cause mood disorders. All parents have experienced the irritability and tantrums of a child who missed a nap or did not sleep well the night before. Adults cannot escape the negative effects of poor sleep either. Often, a nap or a good night’s rest can help restore our typical selves. But when our sleep-wake cycle is consistently disrupted the consequences are far worse. 

It could be the reverse, that mood disorders cause poor sleep. Or there could be some other factor that the researchers did not measure that links disturbances to the sleep-wake cycle to mood disorders such as melatonin levels.

So, what can we do with this information? First, it is important to understand our sleep habits before making any changes. Try keeping a sleep diary. Then make changes to ensure that you’re practicing good sleep hygiene. Good sleep hygiene includes going to sleep and waking up at the same time every day, avoiding alcohol before bed, and staying away from electronics at least 30 minutes before bedtime. If your sleep problems persist, seek help from a professional.

Read more about the study:

Disrupted sleep-wake cycle linked to mental health problems – new study.