Family History of Panic Disorder and Hypersensitivity to CO sub 2 in Patients With Panic Disorder

Perna, Giampaolo MD
Bertani, Angelo MD
Caldirola, Daniela MD
Bellodi, Laura MD

Received July 27, 1995; revision received Jan. 31, 1996; accepted March 18, 1996. From the Anxiety Disorders Clinical and Research Unit, Department of Neuropsychiatric Sciences, San Raffaele Hospital. Address reprint requests to Prof. Bellodi, Anxiety Disorders Clinical and Research Unit, Department of Neuropsychiatric Sciences, San Raffaele Hospital, 29 via Prinetti 20127, Milan, Italy.
The authors thank E. Politi, M.D., for assistance in statistical analyses and C. Cavallini, M.D., for comments on the paper.

American Journal of Psychiatry 153(8):p 1060-1064, August 1996.

Objective

The authors investigated the relationships between hypersensitivity to CO₂ and familial-genetic risk for panic disorder in patients with panic disorder. Method: Morbidity risks for panic disorder were calculated for families of 203 patients with panic disorder, each of whom was challenged with 35% CO₂. Results: Patients who reacted with a positive response to the 35% CO₂ challenge showed a genetic risk for panic disorder (morbidity risk = 14.4%) that was significantly higher than that for patients who did not react (morbidity risk = 3.9%). Conclusions: These findings support the idea that hypersensitivity to CO₂ might be associated with a subtype of panic disorder specifically related to a greater familial loading.

(Am J Psychiatry 1996; 153:1060-1064)