Bipolar disorder can cause extreme mood swings from euphoric recklessness at one extreme to paralysing depression at the other. It can recur throughout people's lives and a team of Swedish researchers tracked a group of bipolar patients over five years after their first admission to hospital in 2000. 60% of the participants had had no readmission but a smaller group (15%) had had 66 readmissions between them. On average the participants were readmitted 1.2 times over the course of the study but those people who had been admitted to hospital for a second time had an average of 1.9 admissions subsequently. Overall three quarters of the hospitalizations were repeat admissions.
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