To characterize the nature of rapid cycling affective disorders, the
authors analyzed mood fluctuation patterns in 570 patients with affective
disorders hospitalized in 1960, 1975, or 1985. Patients' records were rated
for the frequency, duration, and complexity of distinct affective states.
Very rapid mood fluctuations were absent among bipolar patients in 1960 but
were evident in 1975 and 1985. In each year, bipolar patients displayed
more frequent, complex, and mixed episodes than did unipolar patients. The
results suggest that more frequent episodes occur among bipolar than
unipolar patients and that very rapid switch processes have become more
widespread for some bipolar patients.Abstract Teaser