Lactate infusion induces panic attacks in patients with premenstrual syndrome.

A sodium lactate test was performed during the premenstrual phase in 35 women suffering from prospectively confirmed premenstrual syndrome (PMS) and in 16 controls in order to assess whether these patients were sensitive to this test and whether this sensitivity was accounted for primarily by the presence of concomitant panic disorder. Patients with PMS also underwent the Structured Clinical Interview for the DSM-III-R (SCID) to determine the presence of co-morbid anxiety and/or mood disorders. Only 31\% of the PMS patients were free from a depressive/anxiety disorder, while nine patients met criteria for panic disorder, and the remaining 15 subjects were diagnosed as having anxiety and/or mood disorders. Lactate infusion induced panic attacks in 22 subjects (62.9\%) and two controls (12.5\%). Panickers were equally distributed among PMS patients with or without a concurrent anxiety/mood disorder. Although cardiovascular responses to lactate were similar among PMS patients regardless of the presence of concomitant anxiety/mood disorders, both plasma cortisol levels and panic and mood scores were higher during the test in those patients with concomitant panic disorder. These results suggest that PMS patients display an increased sensitivity to lactate, which is not primarily accounted for by the presence of co-morbid panic disorder.