Comorbid major depression and panic disorder: significance of temporal sequencing to familial transmission.

BACKGROUND

Panic disorder (PD) and major depression frequently coexist but the nature of the relationship is controversial. Our aim was to determine if the risk for depression in a proband is influenced by the temporal sequence of comorbid PD and major depression in an affected family member.

METHODS

Of participants in a larger study of individuals who had a family, but no personal history of PD, 31 had a first-degree relative with comorbid PD and major depressive disorder (MDD). In 16, the onset of MDD preceded PD (HR-MDPD), and in 15, PD was established before the first depressive episode (HR-PDMD). Thirty-seven low-risk controls (LRC) described no first-degree relatives with psychiatric illness. Participants were assessed using the SADS-LA and provided family history data on first-degree relatives.

RESULTS

High-risk subjects whose first-degree relative had temporally primary depression had a 50% chance of having had a major depressive episode. Those with a first-degree relative with primary panic and secondary depression were at no greater risk of having had a depression than were normal controls (6.7% and 5.4%, respectively).

LIMITATIONS: The use of the family history method has the intrinsic weakness of relying solely on proband knowledge.

CONCLUSION

The temporal relationship between comorbid panic and depression may play an important role in determining the familial risk for depression in family members.