Chronotype in bipolar disorder: an 18-month prospective study.

Objective: Circadian dysregulation plays an important role in the etiology of mood disorders. Evening chronotype is frequent in these patients. However, prospective studies about the influence of chronotype on mood symptoms have reached unclear conclusions in patients with bipolar disorder (BD).

Sleep and circadian alterations in people at risk for bipolar disorder: A systematic review.

Background: Sleep and circadian abnormalities have been mostly demonstrated in bipolar patients. However, it is not clear whether these alterations are present in population at high risk for bipolar disorder (BD), indicating a possible risk factor for this condition.

Objective: This systematic review aims to define current evidence about sleep and rhythm alterations in people at risk for BD and to evaluate sleep and circadian disorders as risk factor for BD.