Daily rest-activity patterns in the bipolar phenotype: A controlled actigraphy study

Figures & data

Table 1. Demographics of the bipolar phenotype group and control group.

	Group		Test statistics
	Bipolar phenotype	Controls	χ^2 (df)	t (df)	p
Gender: n (%)			0.100 (1)		0.752
Female	10 (53)	10 (48)
Male	9 (47)	11 (52)
Age (years): mean (SD)	20.1 (0.9)	20.8 (1.7)		1.455 (38)	0.154
Subjective mood: mean (SD)
HAM-D	3.4 (2.6)	1.7 (1.6)		2.494 (38)	0.017
YMRS	3.6 (3.0)	1.3 (1.2)		3.157 (38)	0.003
Diagnoses: n (%)
Bipolar II disorder	4 (21)
Bipolar NOS	3 (16)
Major depressive disorder	2 (11)
Anxiety co-morbidity	4 (21)
Family history of unipolar depression or anxiety disorder	3	3
Chronotype (scores): n (%)			1.450 (4)		0.835
Extreme evening (16–30)	3 (17)	3 (14)
Moderate evening (31–41)	4 (22)	4 (19)
Neither type (42–58)	7 (39)	10 (48)
Moderate morning (59–69)	3 (17)	4 (19)
Extreme morning (70–86)	1 (6)	0 (0)

Figure 1. Representative examples of rest-activity patterns derived from 2 weeks’ wrist activity monitoring in control (upper panel) and bipolar phenotype (lower panel) female individuals. Actigraphic data are 48-h double plotted with successive days on vertical axis. Midline indicates midnight between day 1 and day 2. Edited data are highlighted with “___”.

Table 2. Parameters of sleep–wake activity in the bipolar phenotype group and control group.

	Group: mean (SD)		Statistical difference
	Bipolar phenotype, N = 19	Controls, N = 21	F-test (df = 1,34)	p
Sleep onset time: hh:mm	01:11 (01:31)	01:08 (00:55)	0.000	0.986
Final wake time: hh:mm	08:28 (01:13)	08:53 (00:51)	0.926	0.343
Total sleep period hh:mm	07:19 (00:43)	07:43 (00:43)	1.606	0.214
Total sleep time: hh:mm	06:15 (00:39)	06:38 (00:40)	2.754	0.106
Sleep onset latency: hh:mm	00:05 (00:03)	00:06 (00:04)	0.071	0.792
Sleep efficiency: %	84.0 (4.5)	84.6 (3.5)	1.773	0.192
Fragmentation index	30.6 (9.2)	27.4 (6.4)	7.891	0.008

Table 3. Parameters of circadian rhythms in activity in the bipolar phenotype group and control group.

	Group: mean (SD)		Statistical difference
	Bipolar phenotype, N = 19	Controls, N = 21	F-test (df = 1,34)	p
M10 onset time: hh:mm	11:18 (01:39)	11:19 (01:44)	0.744	0.394
M10 activity	22590 (3281)	21680 (4463)	0.015	0.903
L5 onset time: hh:mm	02:06 (01:19)	02:21 (00:46)	0.378	0.543
L5 activity	1869 (1068)	1354 (583)	5.859	0.021
Relative amplitude	0.85 (0.09)	0.88 (0.05)	4.366	0.044
Inter-daily stability	0.43 (0.11)	0.44 (0.09)	0.699	0.409
Intra-daily variability	0.98 (0.18)	0.99 (0.19)	0.075	0.786