G. Perna et al., SENSITIVITY TO 35-PERCENT CO2 IN HEALTHY FIRST-DEGREE RELATIVES OF PATIENTS WITH PANIC DISORDER, The American journal of psychiatry, 152(4), 1995, pp. 623-625
Objective: The authors tested the hypothesis that hyperreactivity to C
O2 in healthy subjects represents an underlying familial vulnerability
to panic disorder. Method: One vital-capacity inhalation of 35% CO2 a
nd 65% O-2 was administered to each of 84 patients with panic disorder
, 23 healthy first-degree relatives of probands with panic disorder, a
nd 44 healthy subjects with no family history of panic disorder. Resul
ts: The first-degree relatives of the probands with panic disorder rea
cted significantly more than the healthy subjects and significantly le
ss than the probands. Conclusions: These findings suggest an associati
on between family history of panic disorder and hyperreactivity to 35%
CO2 in healthy subjects.