Influence of quality of sleep in the first trimester on blood pressure in the third trimester in primipara women

Figures & data

Figure 1. Recruitment flow diagram.

Table 1. Participant characteristics.

		All n = 89	PSQI ≦ 5 n＝60	PSQI ≧ 6 n＝29
Characteristic		mean ± SD /n (%)	mean ± SD /n (%)	mean ± SD /n (%)	p-Value
Age		30.2 ± 4.9	30.5 ± 5.2	29.6 ± 4.2	.37
High		159.0 ± 5.5	159.0 ± 5.0	158.9 ± 6.6	.92
Pre-pregnant weight(kg)		50.8 ± 6.2	50.5 ± 6.3	51.5 ± 6.0	.47
Pre-pregnant BMI		20.0 ± 1.9	19.9 ± 1.9	20.3 ± 1.9	.32
Weight increase(kg)		8.0 ± 2.0	8.1 ± 2.0	7.8 ± 2.0	.59
History of gynecology	yes	16 (18.0)	10 (16.7)	6 (20.7)	.44
Medical history	yes	4 (4.5)	4 (6.7)	0 (0.0)	.47
Family history of hypertension	yes	33 (37.1)	22 (36.7)	11 (37.9)	.56
Family history of diabetes housemate's smoked	yes	30 (33.7)	22 (36.7)	8 (27.6)	.54
First trimester	yes	32 (36.0)	22 (36.7)	10 (34.5)	.52
Second trimester	yes	33 (37.1)	24 (40.0)	9 (31.0)	.28
Third trimester	yes	32 (36.0)	22 (36.7)	10 (34.5)	.52
Infant weight(g)		2898.2 ± 323	2920.8 ± 323	2851.6 ± 310.0	.35
Gestational period (weeks)		38.7 ± 1.09	38.7 ± 1.0	38.5 ± 1.2	.42
Deilvery manner
Normal delivery		86 (96.6)	57 (95.0)	29 (100)	.30
Smoking pre-pregnant	yes	15 (16.9)	13 (21.7)	2 (6.9)	.07
First trimester	yes	1 (1.1)	1 (1.7)	0 (0)	.67
Second trimester	yes	3 (3.4)	2 (3.3)	1 (3.4)	.70
Last trimester	yes	2 (2.3)	1 (1.7)	1 (3.4)	.55
Alcohol consumption  Pre-pregnant	yes	62 (69.7)	39 (65.0)	23 (79.3)	.13
First trimester	yes	1 (1.1)	1 (1.7)	0 (0)	.67
Second trimester	yes	2 (2.3)	2 (3.3)	0 (0)	.45
Third trimester	yes	2 (2.3)	1 (1.7)	1 (3.4)	.55
Exercise habits
Pre-pregnant	yes	14 (15.7)	11 (18.3)	3 (10.3)	.25
First trimester	yes	6 (6.7)	5 (8.3)	1 (3.3)	.35
Second trimester	yes	30 (33.7)	19 (31.7)	11 (37.9)	.36
Third trimester	yes	30 (33.7)	22 (36.7)	8 (27.6)	.27
Working status
Pre-pregnant	yes	81 (91.0)	55 (91.7)	26 (89.7)	.52
First trimester	yes	71 (79.8)	46 (76.7)	25 (86.7)	.17
Second trimester	yes	61 (68.5)	39 (63.9)	22 (75.9)	.22
Third trimester	yes	17 (19.1)	10 (16.7)	7 (24.1)	.29
High blood pressure of delivery period		9 (10.1)	6 (10.0)	3 (10)	.96
PSQI-J score		MD IQR	MD IQR	MD IQR	p-Value
First trimester
Global score		4 (3.0–6.0)	3.5 (3.0–4.0)	6 (6.0–7.0)	.00*
Subjective sleep quality		1 (1.0–2.0)	1.0 (1.0–1.0)	2 (1.0–2.0)	.00*
Sleep latency		1 (0.0–1.0)	0.0 (0.0–1.0)	1 (1.0–2.0)	.00*
Sleep duration		0 (0.0–1.0)	0.0 (0.0–1.0)	1 (0.0–1.0)	.00*
Sleep efficiency		0 (0.0–0.0)	0.0 (0.0–0.0)	0 (0.0–0.0)	.18
Sleep disturbances		1 (1.0–1.0)	1.0 (1.0–1.0)	1 (1.0–1.0)	.01*
Sleeping medication		0	0	0
Daytime dysfunction		1 (0.0–2.0)	0.0 (0.0–1.0)	2 (1.0–2.0)	.00*
Second trimester
Global score		4 (30–5.5)	3.5 (3.0–5.0)	5 (4.0–7.0)	.00*
Subjective sleep quality		1 (1.0–1.0)	1.0 (1.0–1.0)	1 (1.0–2.0)	.42
Sleep latency		1 (0.0–1.0)	1.0 (0.0–1.0)	1 (1.0–2.0)	.04*
Sleep duration		0 (0.0–1.0)	0.0 (0.0–1.0)	1 (0.5–1.0)	.00*
Sleep efficiency		0 (0.0–0.0)	0.0 (0.0–0.0)	0 (0.0–0.5)	.07
Sleep disturbances		1 (1.0–1.0)	1.0 (1.0–1.0)	1 (1.0–1.0)	.20
Sleeping medication		0	0	0
Daytime dysfunction		0 (0.0–1.0)	0.0 (0.0–1.0)	1 (0.0–1.0)	.23
Third trimester
Global score		5 (4.0–7.0)	5.0 (3.3–6.0)	6 (4.0–8.5)	.09
Subjective sleep quality		1 (1.0–2.0)	1.0 (1.0–2.0)	2 (1.0–2.0)	.23
Sleep latency		1 (1.0–2.0)	1 (0.3–2.0)	1 (1.0–2.5)	.78
Sleep duration		1 (0.0–1.0)	0.5 (0.0–1.0)	1 (0.0–2.0)	.16
Sleep efficiency		0 (0.0–0.5)	0 (0.0–0.0)	0 (0.0–1.0)	.00*
Sleep disturbances		1 (1.0–1.0)	1 (1.0–1.0)	1 (1.0–1.0)	.59
Sleeping medication		0	0	0
Daytime dysfunction		0 (0.0–1.0)	0 (0.0–1.0)	0 (0.0–1.0)	.45

Continuous variables, such as age, height, weight, BMI, weight increase during pregnancy, infant weight, and gestational period were compared between the good sleep quality group and the poor sleep quality group using the t-test.

Categorical variables, including family history of hypertension, family history of diabetes, other medical history, smoking, alcohol consumption, exercise habits, and employment status were compared between the good sleep quality group and the poor sleep quality group using the chi-square test.

The PSQI-J Global score and the score on each of the 7 components were analyzed between the two groups using the Mann-Whitney test.

The number of weeks corresponding to each trimester were: first trimester, 10 weeks to 14 weeks; second trimester, 22 weeks to 24 weeks; and third trimester, 32 weeks to 36 weeks.

PSQI-J: the Japanese version of the Pittsburgh Sleep Quality Index; SD: standard deviation; BMI: body mass index; MD: median; IQR: interquartile range.

* Comparison between the good sleep quality group (PSQI-J < 5) and the poor sleep quality group (PSQI-J > 6) based on PSQI-J scores in the first trimester (2014–2016).

p-value is <.05*.

Table 2. Change in sleep quality during pregnancy.

The PSQI-J Global score and the scores of each of the 7 components were compared between the good sleep quality group and the poor sleep quality group in the first trimester using the Friedman test for changes from first trimester to third trimester.

PSQI-J: the Japanese version of the Pittsburgh Sleep Quality Index; MD: median; IQR: interquartile range.

Sleep medication was one of the 7 components of the PSQI-J score, but had 0 “yes” answers, and it was therefore removed, leaving 6 components in the analysis.

p-value is <.01**; <.05*.

Table 3. Changes in home blood pressure during pregnancy.

	all	PSQI ≦5	PSQI ≧6
	n = 89	n＝60	n＝29	PSQI-J ≦5 VS ≧6
	mean ± SD	mean ± SD	mean ± SD	p-Value
SBP
Morning
First trimester	100.6 ± 8.2	101.1 ± 8.0	99.4 ± 8.5	.35
Second trimester	100.0 ± 7.6	100.2 ± 7.0	99.6 ± 8.8	.72
Third trimester	104.9 ± 8.7	104.1 ± 8.8	106.5 ± 8.4	.22
Evening
First trimester	100.8 ± 8.0	101.0 ± 7.6	100.3 ± 8.9	.69
Second trimester	99.5 ± 7.3	99.5 ± 7.1	99.4 ± 7.9	.94
Third trimester	105.1 ± 8.4	104.2 ± 8.5	106.9 ± 8.0	.15
DBP
Morning
First trimester	63.7 ± 6.5	64.0 ± 6.8	63.1 ± 6.1	.54
Second trimester	61.8 ± 6.2	62.1 ± 6.4	61.2 ± 5.7	.53
Third trimester	66.2 ± 7.8	66.0 ± 8.5	66.6 ± 6.0	.70
Evening
First trimester	61.8 ± 6.4	62.0 ± 6.4	61.4 ± 6.5	.70
Second trimester	60.6 ± 6.0	61.2 ± 6.1	59.5 ± 5.8	.23
Third trimester	65.1 ± 6.9	65.1 ± 7.2	65.2 ± 6.3	.93
Change of SBP
First trimester - second trimester
Morning	−0.5 ± 5.5	−0.9 ± 5.5	0.2 ± 5.7	.38
Evening	−1.3 ± 5.3	−1.5 ± 5.2	−0.9 ± 5.7	.63
Second trimester - third trimester
Morning	4.8 ± 6.2	3.9 ± 6.3	6.9 ± 5.6	.03*
Evening	5.6 ± 5.6	4.7 ± 5.4	7.5 ± 5.7	.24
First trimester - third trimester
Morning	4.3 ± 6.4	3.0 ± 5.6	7.1 ± 7.0	.003**
Evening	4.3 ± 5.9	3.2 ± 5.7	6.6 ± 5.9	.001**
Change of DBP
First trimester - second trimester
Morning	−1.9 ± 5.3	−1.9 ± 5.3	−1.9 ± 5.6	.99
Evening	−1.2 ± 5.4	−0.8 ± 5.4	−1.9 ± 5.4	.37
Second trimester - third trimester
Morning	4.4 ± 5.9	3.9 ± 6.4	5.4 ± 4.7	.27
Evening	4.5 ± 5.0	3.9 ± 4.9	5.7 ± 5.0	.11
First trimester - third trimester
Morning	2.5 ± 6.3	2.0 ± 5.8	3.5 ± 7.4	.29
Evening	3.3 ± 5.6	3.1 ± 5.0	3.8 ± 6.8	.59

The mean blood pressure was compared between the good sleep quality group and the poor sleep quality group in the first trimester using the t-test.

Changes in blood pressure throughout the course of pregnancy were also compared between the good sleep quality group and the poor sleep quality group using the t-test.

Change values were calculated from the first trimester to the second trimester (mean of second trimester – mean of first trimester), from the second trimester to the third trimester (mean of second trimester – mean of third trimester), and from the first trimester to the third trimester (mean of third trimester – mean of first trimester).

The number of weeks corresponding to each trimester were: first trimester, 10 weeks to 14 weeks; second trimester, 22 weeks to 24 weeks; and third trimester, 32 weeks to 36 weeks.

HBP: home blood pressure; SBP: systolic blood pressure; DBP: diastolic blood pressure; PSQI-J: the Japanese version of the Pittsburgh Sleep Quality Index; SD: standard deviation.

p-Value is <.01**; <.05*.

Table 4. Factors affecting changes in mean systolic blood pressure.

									N = 29
	First trimeser - third trimester morning			First trimester - third trimester evening			Second trimester - third trimester morning
	r	β	p-Value (95%Cl)	r	β	p-Value (95%Cl)	r	β	p-Value (95%Cl)
PSQI-J Global score	0.49	0.58	.007 (1.19 to 6.67)*	0.26	0.29	.18 (−0.79 to 4.09)	0.17	0.09	.68 (−1.91 to 2.89)
Age	0.03	0.19	.36 (−0.38 to 1.03)	0.05	0.12	.58 (−0.46 to 0.80)	−0.23	−0.3	.19 (−1.02 to 0.21)
Pre-pregnancy BMI	−0.17	−0.22	.31 (−2.40 to 0.81)	−0.11	−0.17	.46 (−1.95 to 0.91)	−0.11	−0.27	.26 (−2.19 to 0.62)
Weight gain during gestation	−0.01	−0.13	.53 (−1.91 to 1.00)	−0.22	−0.36	.10 (−2.37 to 0.22)	0	0.03	.90 (−1.20 to 1.35)
Positive family history (hypertension)	−0.02	−0.08	.66 (−6.65 to 4.29)	−0.08	−0.07	.73 (−5.68 to 4.05)	−0.25	−0.33	.12 (−8.50 to 1.07)
Living with a smoker	−0.18	−0.01	.95 (−6.10 to 5.73)	−0.27	−0.24	.26 (−8.17 to 2.35)	−0.09	−0.08	.72 (−6.07 to 4.28)
R^2		0.33			0.25			0.20
Adjust R^2		0.15			0.04			−0.01

The factors affecting first trimester – third trimester, morning; first trimester – third trimester, evening; second trimester – third trimester, morning between the good sleep quality group and the poor sleep quality group in the first trimester were analyzed using multiple regression analysis.

PSQI-J: the Japanese version of the Pittsburgh Sleep Quality Index; BMI: body mass index; Cl: confidence interval.

p-value is <.05*.

Table 5. Components of the PSQI-J score influencing systolic blood pressure in the first trimester to third trimester.

				N = 29
	First trimester - third trimester morning
Components of PSQI-J	r	β	p-Value
Subjective sleep quality	0.33	0.30	.06
Sleep latency	0.38	0.43	.02*
Sleep duration	0.26	0.36	.06
Sleep efficiency	0.37	0.15	.39
Sleep disturbances	0.24	0.33	.04*
R^2		0.49
Adjust R^2		0.38

The types of sleep quality affecting increased SBP from the first trimester to the third trimester morning were analyzed using multiple regression analysis.

Sleep medication was one of the 7 components of the PSQI-J score but had 0 “yes” answers and was therefore removed, leaving 6 components in the analysis.

PSQI-J: the Japanese version of the Pittsburgh Sleep Quality Index.

p-Value is <.05*.