Am J Psychiatry 1994; 151:1148-1152
Copyright © 1994 by American Psychiatric Association
Cardiac and respiratory activity in panic disorder: effects of sleep and sleep lactate infusions
HW Koenigsberg, CP Pollak, J Fine and T Kakuma
Department of Psychiatry, Cornell University Medical College, White Plains, NY.
OBJECTIVE: This study examined cardiac and respiratory activity in panic
disorder patients and healthy comparison subjects during sleep, when the
effects of anxious cognition and expectancy set are minimized. METHOD:
Heart rate, respiratory rate, end-tidal PCO2, and oxygen saturation were
recorded for 11 panic disorder patients and 12 comparison subjects before
and during sleep and before and after infusions of sodium lactate and a
saline control. RESULTS: Panic disorder patients had higher oxygen
saturations than comparison subjects before sleep onset and during sleep
stages 0 and 2 before any infusions. The two groups did not differ on other
respiratory variables and heart rate. Panic disorder patients responded to
lactate infusions during stage 3-4 sleep with greater increases in heart
rate and oxygen saturation, and possibly in respiratory rate and end-tidal
PCO2, than comparison subjects. The saline control infusion had little
effect. CONCLUSIONS: These findings suggest that panic disorder patients
have greater cardiac and respiratory reactivity than healthy comparison
subjects during sleep, when the influence of cognitive factors is minimal
or absent.
