Cortical thinning in young psychosis and bipolar patients correlate with common neurocognitive deficits

International Journal of Bipolar Disorders

Table 3 Demographics and clinical scores (± standard deviation)

	Psychosis *(n =* 40)	Bipolar *(n =* 73)	Controls *(n =* 49)	Significance test *(p)*
Female, % (female/male)	27.5% (11/29)	71.2% (52/21)	57.1% (28/21)	χ² = 20.10 (<0.001)
Right handed, % (r/l/a)	85.0% (34/5/1)	80.8% (59/12/2)	83.7% (41/7/1)	χ² = 0.40 (0.982)
Age, years	23.5 ± 3.4	21.9 ± 3.6	24.2 ± 2.7	F = 7.31 (<0.001) bipolar < controls
Predicted IQ	101.9 ± 8.7	103.8 ± 7.9	104.9 ± 8.3	F = 1.31 (0.272)
Education, years	12.6 ± 2.5	12.8 ± 2.1	14.6 ± 2.1	F = 12.61 (<0.001) psychosis, bipolar < controls
Intracranial volume, cm³	1,557 ± 149	1,510 ± 127	1,532 ± 136	F = 1.57 (0.211)
Age of onset of illness, years	17.7 ± 4.3	14.9 ± 3.5	-	t = −3.75 (<0.001)
Duration of illness, years	5.8 ± 3.5	7.1 ± 3.9	-	t = 1.67 (0.097)
HDRS total	13.4 ± 6.8	12.4 ± 7.0	-	t = −0.75 (0.453)
BPRS total	44.6 ± 9.9	41.2 ± 8.9	-	t = −1.89 (0.062)
BPRS positive symptoms subscore^a	13.8 ± 4.9	11.1 ± 3.6	-	t = −3.05 (0.003)
BPRS negative symptoms subscore	8.8 ± 3.7	6.7 ± 2.3	-	t = −3.14 (0.003)
BPRS depression subscore^a	13.5 ± 4.4	14.2 ± 4.9	-	t = 0.71 (0.481)
BPRS mania subscore^a	9.9 ± 3.3	10.8 ± 4.7	-	t = 1.16 (0.250)
BPRS disorientation subscore^a	2.6 ± 1.2	2.2 ± 0.7	-	t = −2.02 (0.049)
YMRS total^a	3.8 ± 8.1	11.8 ± 16	-	t = 3.66 (<0.001)

Significant differences in gender and handedness were evaluated using a Pearson Chi-square test. Age, predicted IQ and years of education were evaluated with a one-way ANOVA with Games-Howell Post Hoc analysis. All other significance values were evaluated using independent samples t tests. Significance levels were set at p < 0.05. ^aEqual variance was not assumed. BPRS, Brief Psychiatric Rating Scale; HDRS, Hamilton Depression Rating Scale; YMRS, Young Mania Rating Scale.