Sleep and mood in bipolar disorder

Sleep loss can trigger relapse, particularly in the form of mania, in people with a diagnosis of bipolar disorder, finds a study by Cardiff University. The new research, led by Cardiff University PhD student Katie Lewis, from the National Centre for Mental Health ( NCMH ), suggests that one in four individuals with bipolar disorder may be at risk of an episode of high mood following sleep loss. Understanding what factors influence the relationship between sleep and mood episodes could help predict which individuals are most likely to relapse following periods of sleep deprivation, for example, because of long-haul travel or shift work. It could also inform self-management techniques such as e-monitoring. This is the largest study to date reporting on the prevalence of sleep loss as a trigger in individuals with bipolar disorder and the first study to examine sleep loss as a trigger of both manic and depressive episodes in a large sample of individuals with bipolar disorder. The large sample size made it possible for the team to examine whether bipolar subtype (type 1 or type 2), as well as gender, could affect people's vulnerability to sleep loss. Type 1 and type 2 bipolar subtypes can both represent serious mental health conditions, however the main difference between type 1 and type 2 bipolar disorder is that people with type 1 tend to have more severe episodes of high mood, possibly requiring hospitalisation.