“…Rapid cycling and mixed states. Rapid cycling, defined by the occurrence of four or more episodes per year, occurs in 13-20% of bipolar patients (Goldberg and Berk, 2010). Conditions such as hypothyroidism, antidepressants and substance abuse possibly contribute to the development of rapid cycling (Coryell, 2005;Yatham et al, 2005), and this is a concern because patients that are rapid cycling are often less responsive and less adherent to treatment than those with conventional patterns of BD.…”