Bipolar disorder is often associated with poor sleep quality, and previous medical research has demonstrated that it is often the result of depressive and manic episodes.

However, a lack of sleep can also be responsible for activating mania, according to research conducted by a team drawn from the Penn State College of Medicine and University of Michigan Medical School.

The team assessed 216 participants that have bipolar disorder as part of the Prechter Longitudinal Study.

They analysed the effect of sleep quality on mood over a period of two years, which was measured by recording the severity, frequency, and inconsistency of depressive or manic symptoms.

For women, poor sleep quality was linked to a higher frequency of depressive displays, as well as increased severity and unpredictability of mania.

Among men, baseline depression and neuroticism were seen to be stronger signs of indicating likely mood outcome over sleep quality.

The research has been published in the Journal of Affective Disorders.

A spokesperson for the study said: “There is some suggestion from animal models that reproductive hormones affect the circadian rhythm system, which is a biological system that affects our need to sleep.

“It could be that reproductive hormones are biologically affecting sleep in women and therefore also affecting mood outcomes.

“Or, it could have more to do with the type of sleep that women are getting.

“We’ll have to do more investigation into the biological underpinnings to understand that better.”

Researchers have not yet found an answer as to why poor sleep affects women with bipolar disorder more than men that have the same condition.