Table 2. Summary of the observed frequencies differences of co-morbid disorders between the GAIN and TGEN samples, as well as between the underlying family and bipolar singleton samples.

	GAIN	TGEN	GAIN vs. TGEN	Family	Singleton	Family vs. Singleton
Co-morbid Disorder	Freq	Freq	P Value	Freq	Freq	P Value
Alcoholism	46.3	49.0	0.218	42.4	49.6	0.004
Substance Abuse	14.7	18.1	0.033	11.3	18.4	<0.001
Panic Disorder	23.9	27.0	0.105	22.1	26.8	0.031
Agoraphobia	12.2	17.3	0.001	9.8	16.8	<0.001
Simple Phobia	9.6	15.3	<0.001	7.6	14.5	<0.001
Social Phobia	10.0	15.1	<0.001	7.4	14.6	<0.001
Obsessive Compulsive Disorder	7.8	13.5	<0.001	6.6	12.6	<0.001
Anorexia/Bulimia	6.1	10.5	<0.001	5.4	9.6	0.002
Rapid Cycling	57.4	63.3	0.006	50.9	63.9	<0.001
Passive Death Wish	72.9	78.2	0.007	74.1	76.3	0.314
Psychosis	66.6	71.8	0.010	61.8	72.1	<0.001

Key: Family refers to bipolar subjects ascertained through the collection of families for NIMH Waves 1–4. Singleton refers to bipolar subjects ascertained as singleton cases collected as part of Wave 5. Note: Significant differences in co-morbidity were not observed between bipolar subjects with irritable vs. elated mania in either sample, nor were differences observed for gender, age at interview, age at onset, age at first mania, or age at most severe mania for any comparison (i.e., irritable vs. elated mania, GAIN vs. TGEN, family vs. singleton, all p>0.10).