Table 1.
Description of the included studies
| Authors, y | Country | Study design | Sample size | Age range or mean ± SD (SE), y | Health status | Definition of sleep quality | Definition of morbidity | Men, No. (%) | Qualitya %a |
|---|---|---|---|---|---|---|---|---|---|
| Alebiosu et al (2009)20 | Nigeria | Cross‐sectional | 254 | Hypertension: 58.2 ± 9.65 Nonhypertension: 58.7 ± 10.8 | Patients with hypertension and normal patients without known disease | PSQI | JNC 7: SBP ≥140 mm Hg and DBP ≥90 mm Hg or receiving treatment | 123 (48.4) | 50.0 |
| Bansil et al (2011)18, b | United States | Cross‐sectional | 10 308 | 18–39: 38.9%, 40–59: 38.3%, ≥60: 22.7% | General | Answered “often” or “almost always” to any of the 6 items on sleeping habits | JNC 7: SBP ≥140 mmHg and DBP ≥90 mmHg or receiving treatment | 5061 (49.1) | 87.5 |
| Berentzen et al (2014)37 | Netherlands | Cohort | 1481 | Baseline: 11.4 ± 0.3; follow‐up: 12.7 ± 0.4 | General | One variable on nighttime awakenings and three variables on daytime outcomes | None | 722 (48.8) | 63.6 |
| Bruno et al (2013)12, b | Italy | Cross‐sectional | 222 | 56.6 ± 12.5 | Essential arterial hypertension | PSQI | Office BP >140/90 mm Hg with ≥3 antihypertensive drugs or controlled BP with ≥4 drugs, including a diuretic | 113 (50.9) | 100 |
| Colbay et al (2015)16 | Turkey | Cross‐sectional | 94 | Diabetes mellitus: 51.4 ± 8.3; no diabetes mellitus: 50.5 ± 9.8 | With or without type 2 diabetes mellitus | PSQI | None | 37 (39.4) | 62.5 |
| Elliott and Lal (2016)40 | Australia | Cross‐sectional | 206 | 31.63 ± 8.51 | General | PSQI | None | 140 (68.0) | 100 |
| Erden et al (2010)24 | Turkey | Cross‐sectional | 133 | Dipper: 43.3 ± 6.3; nondipper: 44.3 ± 5.3 | Newly diagnosed stage I hypertension | PSQI | Seated SBP ≥140 mm Hg and seated DBP ≥90 mm Hg; dippers: decrease in nighttime systolic BP was at least 10% of the mean daytime values | 60 (45.1) | 100 |
| Henskens et al (2011)36 | Netherlands | Cross‐sectional | 203 | 52.1 ± 12.5 | Hypertension without antihypertensive treatment for ≥2 wk | GSQS | Untreated office SBP ≥140 mm Hg and/or DBP ≥90 mm Hg | 104 (51.2) | 75.0 |
| Huang et al (2011)25 | China | Cross‐sectional | 307 | 18–70; good sleeper: 54.3 ± 7.9; poor sleeper: 55.5 ± 9.5 | Hypertension with lifestyle modification for at least 6 mo and stable antihypertensive medication for >8 wk | PSQI | JNC 7: office SBP ≥140 mm Hg and/or DBP ≥90 mm Hg | 160 (52.1) | 100 |
| Jackowska et al (2016)35 | United Kingdom | Cross‐sectional | 119 | <45; 26 ± 4.9 | General | PSQI | None | 0 (0) | 50.0 |
| Kani et al (2016)49 | Turkey | Case‐control | 95 | 18–60; dipper: 46.4 ± 12.4; nondipper: 47.1 ± 11.9; control: unknown | Dipper and nondipper groups: hypertension; Control: healthy | PSQI | SBP ≥140 mm Hg and DBP ≥90 mm Hg with/without antihypertensive medication; dipping hypertension: >10% decrease in SBP and DBP | Dipper and nondipper group: 33; control: unknown | 50.0 |
| Kaya et al (2014)13, b | Turkey | Case‐control | 74 | Case: 43.7 ± 12.9; control: 45 ± 11.8 | Case: WCH; control: normotension | PSQI | WCH | 32 (43.2) | 80.0 |
| Liu et al (2016)14 | China | Cross‐sectional | 9404 | 20–93; 52.11 ± 14.10 | General | PSQI | JNC 7: SBP ≥140 mm Hg, DBP ≥90 mm Hg, or receiving treatment | 4770 (50.7) | 75.0 |
| Lu (2015)11, b | China | Cross‐sectional | 5461 | Men <45: 39.76 ± 5.08: men >45: 51.43 ± 8.03; women <45: 40.53 ± 3.74; women >45: 49.91 ± 4.46 | General without secondary hypertension, pregnancy hypertension, OSAS, or RLS | PSQI | JNC 7: SBP ≥140 mm Hg, DBP ≥90 mm Hg, or receiving treatment | 4076 (74.6) | 100 |
| Mahmood et al (2013)17 | Ireland | Cross‐sectional | 114 | Good sleeper: 64.0 ± 11.32; poor sleeper: 66.0 ± 10.98 | Type 2 diabetes mellitus | PSQI | None | 62 (54.4) | 62.5 |
| Mesas et al (2014)31, b | Spain | Cross‐sectional | 10342 | No difficulty in falling asleep: 45.2 (0.3); difficulty in falling asleep: 51.1 (0.5) | General | Difficulties in falling asleep | SBP ≥130 mm Hg or DBP ≥85 mm Hg or receiving treatment | 5185 (50.1) | 87.5 |
| Narang et al (2012)34 | Canada | Cross‐sectional | 3372 | 14.6 ± 0.5 | General | PSQI | Prehypertension: >90th to <95th percentile; hypertension: ≥99th percentile | 1650 (48.9) | 87.5 |
| Osonoi et al (2015)15 | Japan | Cross‐sectional | 724 | 25–69; 57.8 ± 8.6 | Type 2 diabetes mellitus | PSQI | None | 456 (62.9) | 87.5 |
| Sekercioglu et al (2015)19 | Canada | Cross‐sectional | 303 | 62.7 ± 14.5 | Chronic kidney disease | PSQI | None | 178 (58.7) | 62.5 |
| Senthil and Krishnadasa (2016)39 | India | Cross‐sectional | 84 | 18–23; 19.69 ± 0.878 | At least one known risk factor of hypertension | PSQI | JNC 7: prehypertension SBP 120–139 mm Hg; DBP 80–89 mm Hg | 40 (47.6) | 37.5 |
| Sforza et al (2014)41, b | France | Cross‐sectional | 500 | 72.0 ± 1.1 | General without insomnia | PSQI | SBP > 140 mm Hg or DBP > 90 mm Hg, receiving treatment, or 24‐h monitoring revealing a diurnal mean SBP > 135 mm Hg or DBP > 85 mm Hg; dippers: nocturnal SBP fell > 10% from daytime values | 220 (44.0) | 100 |
| Sherwood et al (2011)38 | United States | Cross‐sectional | 128 | 40–60; 45.7 ± 8.4 | Untreated hypertension | PSQI | JNC 7: SBP 130–159 mm Hg and/or DBP 85–99 mmHg | 76 (59.4) | 87.5 |
| Suh (2013)51 | United States | Cross‐sectional | 30 | 25–60; 40.82 ± 6.69 | General | PSQI | Nondippers were defined as those whose average nighttime SBP dropped <10% from the average daytime SBP | 0 (0) | 62.5 |
| Tavasoli et al (2015)32 | Iran | Cross‐sectional | 76 | Age range of all participants: 5–15; good sleepers: 7.4 ± 2.7; poor sleepers: 7.7 ± 2.6 | Urinary tract infection | PSQI | SBP or DBP ≥95 percentile for age, sex, and height. A <10% SBP drop during sleep was considered a nondipper state. | 19 (25.0) | 62.5 |
| Ulmer et al (2013)33 | United States | Cross‐sectional | 61 | 38.28 ± 12.08 | PTSD (either with or without depression), women with depression only (no PTSD), and a comparison group of women without PTSD or depression | PSQI | Dippers were defined as those having a day vs night difference in BP ≥10% of daytime BP | 0 (0) | 75.0 |
| Ulu et al (2013)36 | Turkey | Cross‐sectional | 100 | Dipper: 47.6 ± 14; nondipper: 55.2 ± 15 | Normotension | PSQI | None | 45 (45.0) | 75.0 |
| Yilmaz et al (2007)50 | Turkey | Cross‐sectional | 73 | 19–64 dipper: 48.5 ± 12.8; nondipper: 47.5 ± 11.9 | Stage I hypertension | PSQI | SBP 141–159 mm Hg and DBP 91–99 mmHg | 45 (61.6) | 50.0 |
| Yue et al (2012)42, b | China | Cross‐sectional | 660 | 93.5 ± 3.4 | General without secondary hypertension | PSQI | JNC 7: SBP ≥140 mmHg, DBP ≥90 mmHg, or receiving treatment | 216 (32.7) | 100 |
| Yuksel (2014)52 | Turkey | Cross‐sectional | 113 | 41.0 ± 10.7 | Normotension and healthy | PSQI | None | 81 (71.7) | 62.5 |
DBP, diastolic blood pressure; GSQS, Groningen Sleep Quality Scale; JNC 7, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; OSAS, obstructive sleep apnea syndrome; PSQI, Pittsburgh sleep quality index; PTSD, posttraumatic stress disorder; RLS, restless legs syndrome; SBP, systolic blood pressure; SD, standard deviation; SE, standard error; WCH, white‐coat hypertension.
Measured by the Joanna Briggs Institute tool.
Adjusted covariates among studies that examined the associations between poor sleep quality and the risk of hypertension using regression analysis.
Bansil et al: sex, age, body mass index, race, poverty status, diabetes mellitus, and smoking; Bruno et al: age, sex, previous cardiovascular events, diabetes mellitus, obesity, depressive symptoms, trait anxiety, and psychiatric drug use; Kaya et al: age, body mass index, sex, and diabetes mellitus; Lu et al: age, body mass index, total cholesterol, triglycerides, fasting blood glucose, exercise habit, status of smoking, status of drinking, and scores on the Generalized Anxiety Disorder 7‐Item Questionnaire and Patient Health Questionnaire 9; Mesas et al: sex, age, educational level, occupation‐based social class, smoking, alcohol intake, binge drinking, coffee intake, comorbidities, sleep duration, total energy intake and Mediterranean Diet Adherence Screener score, physical activity, time watching TV, and antihypertensive or lipid‐lowering drug treatment; Sforza et al: sex, body mass index, glycemia, dyslipidemia, current smoking, Hypnotic Intake, and Epworth Sleepiness Scale; Yue et al: age, blood pressure (BP), body mass index, blood glucose level, smoking habit, alcohol consumption, tea consumption, and exercise.