Sleep characteristics in child and adolescent offspring of parents with bipolar disorder: a case control study

BMC Psychiatry

Table 4 Results of actigraphic measures in offspring

	OB		CO		p-value
	(N = 31)		(N = 27)		p-value
Female/Male	13/18		12/15		1.0^a
Age, mean, (SD)	12.8 (3.0)		11.9 (3.3)		0.3^b
Any bipolar spectrum disorder^c, N (%)	4 (12.9)		0 (0.0)		0.1^a
Any mood spectrum disorder^d, N, (%)	3 (9.7)		0 (0.0)		0.2^a
Any anxiety spectrum disorder^e, N, (%)	6 (19.4)		4 (14.8)		0.7^a
ADHD	9 (29.0)		1 (3.7)		0.01^a
Not currently mentally ill, N, (%)	16 (52)		22 (81)		0.03^a
Non-Parametric Circadian Rhythm Analysis
Weekdays	Mean	SD	Mean	SD
Interdaily Stability	0.70	0.11	0.70	0.10	0.8^c
Intra-Daily Variability	0.86	0.20	0.81	0.18	0.4^c
Relative Amplitude	0.95	0.03	0.96	0.02	0.5^c
Weekends
Interdaily Stability	0.74	0.10	0.74	0.06	0.4^c
Intra-Daily Variability	0.75	0.22	0.78	0.17	0.6^c
Relative Amplitude	0.93	0.09	0.96	0.02	0.4^c
Sleep macrostructure
Weekdays	Mean	SD	Mean	SD
Sleep onset latency, h:min	0:51	0:39	0:39	0:21	0.05^c
Actual sleep time, h:min	7:35	0:47	7:33	0:50	0.5^c
Sleep efficiency, %	72.5	5.4	73.6	5.4	0.3^c
Fragmentation Index	26.6	5.4	29.0	7.1	0.2^c
Weekends
Sleep onset latency, h:min	0:56	0:37	0:39	0:21	0.2^c
Actual sleep time, h:min	7:59	0:47	7:57	0:50	0.8^c
Sleep efficiency, %	72.3	6.3	72.9	7.0	0.5^c
Fragmentation Index	30.3	7.6	31.6	8.3	0.5^c

ADHD attention-deficit hyperactivity disorder, CO control offspring, h hour, min minutes, N number, OB high-risk offspring, SD standard deviation
^aFisher’s exact test;
^bunpaired t-test;
^cMann-Whitney test
^dincluding BD II, BD NOS and cyclothymia
^eincluding major mood disorder, depression NOS, depressive adjustment disorder and dysthymia
^fincluding generalised anxiety disorder, social and separation anxiety

ISSN: 1471-244X