Mood-Incongruent Psychotic Features in Bipolar Disorder: Familial Aggregation and Suggestive Linkage to 2p11-q14 and 13q21-33

Objective: Mood-incongruent psychotic features in bipolar disorder may signify a more severe form of the illness and might represent phenotypic manifestations of susceptibility genes shared with schizophrenia. This study attempts to characterize clinical correlates, familial aggregation, and genetic linkage in subjects with these features. Method: Subjects were drawn from The National Institute of Mental Health (NIMH) Genetics Initiative Bipolar Disorder Collaborative cohort, consisting of 708 families recruited at 10 academic medical centers. Subjects with mood-incongruent and mood-congruent psychotic features were compared on clinical variables. Familial aggregation was tested using a proband-predictive model and generalized estimating equations. A genome-wide linkage scan incorporating a mood-incongruence covariate was performed. Results: Mood-incongruent psychotic features were associated with an increased rate of hospitalization and attempted suicide. A proband with mood-incongruence predicted mood-i...