The Efficacy of Tai Chi and Qigong Exercises on Blood Pressure and Blood Levels of Nitric Oxide and Endothelin-1 in Patients with Essential Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Table 2

Characteristics of included studies.

Study ID	Sample (E/C)	Age (years)	Sex (M/F)	Diagnosis standard	Hypertension classification (E/C)	Frequency	Experimental groups	Control groups	Duration	Outcome indicators	Dropout (E/C)
Chen [45]	30/30	66.3 ± 5.8	NR	NR	EH	44 min/day, 5 days/week	Qigong (Mawangdui Daoyinshu)	No intervention	6 months	SBP, DBP, NO, ET-1	NR
Chen [46]	30/30	E: 69.23 ± 3.72; C: 70.06 ± 3.51	E: 13/14; C: 16/12	GPTHC (2005 edition)	EH, stage I (60)	30 min/day, 5 days/week	Qigong (Baduanjin) + antihypertensive drug	Antihypertensive drug (amlodipine besylate 5 mg qd or telmisartan 80 mg qd)	3 months	SBP, DBP, NO, ET-1	3/2
Chen [47]	20/20	E: 64.3; C: 60.7	E: 9/11; C: 13/7	GPTHC (2004 edition)	EH, stage II (26), stage III (14)	40 min/day, 7 days/week	Chen-style Tai Chi + antihypertensive drug	Antihypertensive drug (nifedipine sustained-release tablets, EH of stage II: 25 mg bid; EH of stage III: 50 mg bid)	2.5 months	SBP, DBP, NO	0/0
Fu [48]	30/30	E: 57.93 ± 6.63; C: 59.53 ± 7.46	E: 20/10; C: 19/11	GPTHC (2010 edition)	EH, stage I (24/21), stage II (6/9)	40 min/day, 6 days/week	Qigong (self-compiled) + antihypertensive drug	Antihypertensive drug (CCB, ACEI, ARB, DAD.; NR specific drug and dosage)	3 months	SBP, DBP, NO, ET-1	NR
Jin et al. [49]	27/27	56.9 ± 5.7	11/43	GPTHC (2010 edition)	EH, stage I (54)	40 min/day, 7 days/week	24-movement Yang-style Tai Chi	Antihypertensive drug (amlodipine 2.5 mg qd)	1.5 months	SBP, DBP, NO, ET-1	0/0
Liu [50]	30/30	E: 56.8 ± 6.78; C: 56.33 ± 7.16	E: 16/14; C: 19/11	GPTHC (2015 edition)	EH, stage I (19/21), stage II (11/9)	40 min/day, 5 days/week	24-movement Yang-style Tai Chi + antihypertensive drug	Antihypertensive drug (amlodipine besylate 5 mg qd)	3 months	NO, ET-1	NR
Xiao et al. [51]	24/24	65.6 ± 7.8	NR	NR	EH	40 min/day, 5 days/week	Qigong (Baduanjin)	No intervention	6 months	SBP, DBP, NO, ET-1	NR
Xiao [52]	42/42	E:60.2 ± 4.6; C: 60.5 ± 4.9	E: 24/18; C: 22/20	GPTHC (2010 edition)	EH	60 min/day, 5 days/week	8-style Tai Chi + aerobic exercise	Aerobic exercise (jog and walk fast)	3 months	SBP, DBP, NO, ET-1	NR
Xie et al. [53]	25/25	60–70	E: 11/14; C: 14/11	GPTHC (2005 edition)	EH, stage I (20), stage II (30)	60 min/day, 5 days/week	24-movement Yang-style Tai Chi	No intervention	3 months	SBP, DBP, NO	NR

E: experimental group, C: control group, M: male, F: female, EH: essential hypertension; NR: not reported; GPTHC: Guidelines for Prevention and Treatment of Hypertension in China, SBP: systolic blood pressure, DBP: diastolic blood pressure, NO: nitric oxide, ET-1: endothelin-1, CCB: calcium channel blockers, ACEI: angiotensin-converting enzyme inhibitor, ARB: angiotensin receptor blocker, DAD: diuretic antihypertensive drug, qd: quaque die/once day, bid: bis in die/twice day. Diagnosis standard: GPTHC (2004 edition): phase II (160 mmHg ≤ SBP ≤ 179 mmHg and/or 100 mmHg ≤ DBP ≤ 109 mmHg), phase III (SBP ≥ 180 mmHg and/or DBP ≥ 110 mmHg). GPTHC (2005 edition): phase I (140 mmHg ≤ SBP ≤ 159 mmHg, and/or 90 mmHg ≤ DBP ≤ 99 mmHg), phase II (160 mmHg≤ SBP < 180 mmHg and/or 100 mmHg ≤ DBP < 110 mmHg). GPTHC (2010 edition): phase I (140 mmHg ≤ SBP ≤ 159 mmHg and/or 90 mmHg ≤ DBP ≤ 99 mmHg), phase II (160 mmHg ≤ SBP < 179 mmHg and/or 100 mmHg ≤ DBP < 109 mmHg). GPTHC (2015 edition): phase I (140 mmHg ≤ SBP ≤ 159 mmHg and/or 90 mmHg ≤ DBP ≤ 99 mmHg), phase II (160 mmHg ≤ SBP ≤ 179 mmHg and/or 100 mmHg ≤ DBP ≤ 109 mmHg). Additional description: the 8-style Tai Chi is also called Yi-duan Quan and adopts the eight main and basic movements of Yang-style Tai Chi. There are 10 movements in the 8-style Tai Chi (including starting and ending). The exercise moves from slow to slightly fast and then from slightly fast to slowly end. Chen-style Tai Chi is characterized by the combination of Yin and Yang and the combination of hardness and softness. This exercise has slow/soft movements similar to the Yang-style and fast/hard movements similar to aerobic exercises.