The Association between Hypertension and Insomnia: A Bidirectional Meta-Analysis of Prospective Cohort Studies
Table 2
Subgroup analyses of the association between insomnia and hypertension.
No. of reports
OR (95% CI)
value for heterogeneity
I2 (%)
Subgroup analyses
Age
<40
1
2.89 (0.76–11.07)
—
—
40–60
14
1.10 (1.05–1.15)
<0.001
85.2
>60
5
1.12 (1.09–1.16)
0.810
0
Sex1
Male (<40%)
6
1.10 (1.03–1.17)
<0.001
81.0
Male (40%–60%)
12
1.12 (1.08–1.15)
0.294
15.4
Male (>60%)
2
1.40 (0.78–2.52)
<0.001
97
Continent
North America
10
1.07 (1.01–1.13)
<0.001
79.1
Asia
3
1.40 (0.94–2.08)
0.011
77.9
Europe
7
1.14 (1.04–1.25)
0.001
72.5
Follow-up time
>5
11
1.06 (1.02–1.10)
<0.001
81.9
≤5
9
1.27 (1.12–1.43)
0.008
55.6
Insomnia subtype2
DIS/DFA
4
1.26 (0.87–1.84)
0.004
77.9
DMS
4
1.17 (0.89–1.55)
0.001
83.0
EMA
2
1.13 (1.07–1.20)
0.566
0
NRS
1
1.39 (0.78–2.48)
—
—
Composite insomnia
15
1.12 (1.06–1.17)
<0.001
79.9
Hypertension assessment
SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg or use of antihypertensive medication
9
1.21 (1.10–1.33)
<0.001
86.9
Others (self-report or different levels of BP or ICD9/10)
11
1.04 (1.01–1.08)
0.001
66.3
Insomnia assessment
Clinical diagnostic criteria
3
1.03 (0.91–1.17)
0.448
0
Non-clinical insomnia criteria
17
1.12 (1.07–1.17)
<0.001
86.3
CI, confidence interval; OR, odds ratio. HTN, hypertension; BP, blood pressure; EMA: early morning awakening; DMS, difficulty maintaining sleep; DIS; difficulty initiating sleep; DFA; difficulty falling asleep; NRS; non-restorative sleep. 1The variable “sex” was used as a continuous variable (according to the proportion of males in each study). 2One study provided data on DMS and DIS/DFA. Two studies provided data on DMS, DIS/DFA, and EMA. One study provided data on DIS/DFA and NRS. One study provided data only on DMS. Therefore, there are 26 reports from 20 studies.
