Laterality of pain in migraine with comorbid unipolar depressive and bipolar II disorders

The purpose of the present study has been to examine differences in the laterality of pain in patients with migraine and comorbid unipolar depressive (UP) and bipolar II (BP II) disorders.Semi-structured interviews of 102 patients with major affective disorders were conducted, using DSM-IV criteria for affective disorders combined with Akiskal's criteria for affective temperaments and International Headache Society criteria for migraine. The group of patients reported on in the present study encompass 47 subjects with UP (n = 24) or BP 11 (n = 23) disorders. Fifteen of the bipolar II patients fulfilled DSM-IV criteria while eight were diagnosed according to the broader criteria of Akiskal.Sixteen of the 38 patients with migraine headaches had bilateral pain or pain equally often on the left or right side while 22 had pain predominantly located on one side. Among the UP patients the pain was most often on the right side (8/10) while among the BP II patients the pain was most often on the left (9/12, p = 0.01). Apart from the presence of hypomanic symptoms in the BP II group there were no clinical or demographic characteristics that distinguished these two sub-groups of affective disorders.These results indicate that there may be a differential affection of the cerebral hemispheres in patients with migraine and comorbid unipolar depressive disorder versus patients with migraine and comorbid bipolar II disorder.