Elevated serum lactate associated with panic attacks induced by hyperventilation.

Several lines of evidence suggest that lactate metabolism may be altered in panic disorder. We recently reported exaggerated increases in serum lactate in panic patients following hyperventilation during glucose infusion. In the current study, lactate metabolism was stimulated by hyperventilation following glucose ingestion in 12 panic patients and 12 controls. The seven patients who panicked during hyperventilation exhibited larger increases in serum lactate levels than nonpanicking patients or controls. The lactate response was significantly correlated with peak ratings of anxiety and panic symptoms, but not correlated with insulin or cortisol levels, heart rate, pCO2, adiposity, exercise habits, or diet. Hyperventilation-induced panic appears to be associated with metabolic changes leading to elevated serum lactate.