Slow and rapid onset of manic episodes: implications for underlying biology

The authors describe affectively ill patients with two different patterns of manic onset observed during medication-free periods. One group of patients had rapid onsets in which the full severity of mania was achieved largely by day 1 of a manic episode; a second group had slower onsets, gradually reaching maximal severity of mania later in an episode. Compared to gradual onset patients, those with the rapid onset manic patterns were ill significantly longer, had a greater number of previous depressive episodes, and had more manic and depressive episodes in the year before hospital admission. The clinical and theoretical implications of these data suggesting that patients with a more rapidly cycling and progressive course have an altered pattern of manic onsets are discussed.