When Thinking Impairs Sleep: Trait, Daytime and Nighttime Repetitive Thinking in Insomnia

Figures & data

Table 1 Study 1: Regression coefficients for sleep efficiency, total sleep time, sleep onset latency, wake after sleep onset, and sleep quality.

	SE		TST		SOL		WASO		SQ
	B (SE)	β	B (SE)	β	B (SE)	β	B (SE)	β	B (SE)	β
Step 1
Anxiety (HADS)	0.42(0.36)	0.13	2.00 (2.21)	.10	‒1.03 (1.16)	‒.11	‒1.03 (1.74)	‒.07	0.03 (0.02)	.18
Depression (CESD)	‒0.11(0.14)	‒.09	‒0.75 (0.85)	‒.10	0.53 (0.44)	.15	‒0.09 (0.66)	‒.02	‒0.02 (0.01)	‒28*
Age	‒0.39(0.07)	‒.46***	‒2.49 (0.41)	‒.47***	0.38 (0.21)	.15	1.41 (0.32)	.36***	‒0.01 (0.003)	‒.30**
R^2adj	20.4%		21.0%		1.0%		12.9%		8.8%
Step 2
Anxiety (HADS)	0.33 (0.40)	.10	0.94 (2.43)	.05	‒0.42 (1.27)	‒.05	‒1.47 (1.91)	‒.10	0.01 (0.02)	.18
Depression (CESD)	‒0.12 (0.15)	‒.10	‒1.00 (0.93)	‒.13	0.48 (0.49)	.14	‒0.08 (0.66)	‒.02	‒0.02 (0.01)	‒.37**
Age	‒0.38 (0.07)	‒.45***	‒2.35 (0.43)	‒.45***	0.32 (0.23)	.13	1.46 (0.34)	.37***	‒0.01 (0.004)	‒.24**
Rumination (RRS)	‒0.02 (0.10)	‒.02	0.02 (0.64)	.00	0.40 (0.33)	.15	‒0.23 (0.50)	‒.06	0.01 (0.01)	.14
Worry (PSWQ)	0.06 (0.11)	.07	0.65 (0.65)	.12	‒0.59 (0.34)	‒.23φ	0.39 (0.52)	.10	0.01 (0.01)	.12
∆ R^2adj	‒0.9%		‒0.5%		1.0%		‒0.9%		0.8%

Note. φ: p < .1; * = p < .05; SE = Sleep efficiency; SOL = Sleep onset latency; SQ = sleep quality (1-5); TST = Total sleep time; WASO = Wake after sleep onset.

Table 2 Study 2: Multilevel regression analyses for sleep efficiency, total sleep time, sleep onset latency, wake after sleep onset, terminal wakefulness, and sleep quality.

	b	(SE)	β	(SE)
	Sleep efficiency - SE
Constant	72.7	(6.65)***
Day	0.67	(0.46)	0.06	(0.04)
Baseline
Anxiety (HADS-A)	0.07	(0.74)	0.01	(0.11)
Depression (CES-D)	0.20	(0.30)	0.08	(0.12)
Repetitive thought (PTQ)	0.26	(0.16)	0.16	(0.10)
Diary
Nighttime worry (APSQ)	-1.19	(0.16)***	-0.53	(0.08)***
Daytime worry (APSQ)	0.33	(0.18)φ	0.14	(0.08)φ
Stress (DASS)	0.12	(0.33)	0.02	(0.07)
R^2		13.9%
	Total sleep time - TST
Constant	361.8	(35.91)***
Day	7.52	(2.49)**	0.12	(0.04)**
Baseline
Anxiety (HADS-A)	0.23	(4.03)	0.01	(0.10)
Depression (CES-D)	0.77	(1.64)	0.06	(0.12)
Repetitive thought (PTQ)	1.67	(0.88)	0.18	(0.09)
Diary
Nighttime worry (APSQ)	-6.67	(0.88)***	-0.54	(0.07)***
Daytime worry (APSQ)	1.39	(0.99)	0.11	(0.08)
Stress (DASS)	0.72	(1.77)	0.03	(0.06)
R^2		17.1%
	Sleep onset latency - SOL
Constant	10.41	(14.96)
Day	-1.25	(0.83)	-0.05	(0.03)
Baseline
Anxiety (HADS-A)	1.11	(1.78)	0.08	(0.12)
Depression (CES-D)	-0.82	(0.72)	-0.16	(0.14)
Repetitive thought (PTQ)	0.29	(0.39)	0.08	(0.11)
Diary
Nighttime worry (APSQ)	2.35	(0.31)***	0.51	(0.07)***
Daytime worry (APSQ)	-0.63	(0.35)^φ	-0.13	(0.07)^φ
Stress (DASS)	-0.63	(0.61)	-0.06	(0.06)
R^2		12.5%
	Wake after sleep onset - WASO
Constant	58.34	(17.52)
Day	-1.84	(1.40)	-0.06	(0.04)
Baseline
Anxiety (HADS-A)	-0.40	(1.88)	-0.02	(0.10)
Depression (CES-D)	-0.45	(0.77)	-0.07	(0.11)
Repetitive thought (PTQ)	-0.76	(0.41)	-0.17	(0.09)
Diary
Nighttime worry (APSQ)	2.16	(0.48)***	0.36	(0.08)***
Daytime worry (APSQ)	-0.28	(0.53)	-0.04	(0.08)
Stress (DASS)	-0.26	(0.96)	-0.02	(0.07)
R^2		7.6%
	Terminal wakefulness - TWAK
Constant	60.64	(15.58)
Day	0.89	(1.23)	0.03	(0.04)
Baseline
Anxiety (HADS-A)	-0.52	(1.68)	0.03	(0.10)
Depression (CES-D)	-0.06	(0.69)	-0.01	(0.12)
Repetitive thought (PTQ)	-0.56	(0.37)	-0.14	(0.09)
Diary
Nighttime worry (APSQ)	0.91	(0.42)*	0.17	(0.08)*
Daytime worry (APSQ)	-0.64	(0.47)	-0.12	(0.09)
Stress (DASS)	-0.19	(0.84)	-0.02	(0.07)
R^2		3.9%
	Sleep quality - SQ
Constant	3.08	(0.24)***
Day	0.04	(0.02)^φ	0.08	(0.05)^φ
Baseline
Anxiety (HADS-A)	-0.02	(0.02)	-0.08	(0.08)
Depression (CES-D)	0.00	(0.01)	0.01	(0.10)
Repetitive thought (PTQ)	0.01	(0.005)*	0.20	(0.08)*
Diary
Nighttime worry (APSQ)	-0.06	(0.01)***	-0.62	(0.08)***
Daytime worry (APSQ)	0.02	(0.01)**	0.23	(0.09)**
Stress (DASS)	0.01	(0.01)	0.05	(0.07)
R^2		16.6%

Note. Baseline variables (anxiety, depression, repetitive thought) are the level 2 variables and are measured only once (before filling out the diary). Diary variables (worry and stress) are the level 1 variables and are measured for seven subsequent days. ‘Day’ is a diary variable (Level 1) and is entered in the model as control variable that indicates which day of the diary was filled out (e.g. Tuesday or Friday). φ = p < .1; * = p < .05; ** = p < .01; *** = p < .001.