Antihypertensive effects of bioactive tripeptides—a random effects meta-analysis

Figures & data

Table I. Study characteristics.

Study (reference)	Country	n	Mean age	Gender (% male)	Design	Duration (weeks)	Product	Dose (mg/d)
Hata et al. 1996 (14)	Japan	30	75.0	27	P, SB	8	milk drink	2.6
Kajimoto et al. 2001a (15)	Japan	81	45.9	73	P, DB	8	tablet	4.2
Kajimoto et al. 2001b (16)	Japan	30	52	40	P, DB	8	milk drink	4
Kajimoto et al. 2002 (17)	Japan	64	50	52	P, DB	8	milk drink	3.8
Hirata et al. 2002 (18)	Japan	32	50	47	P, DB	8	milk drink	4.3
Seppo et al. 2002 (19)	Finland	17	49.6	49	P, DB	8	milk drink	5.3
Seppo et al. 2003 (20)	Finland	39	47.8	29	P, DB	21	milk drink	5.3
Mizushima et al. 2004 (21)	Japan	46	46.4	100	P, DB	4	milk drink	2
Nakamura et al. 2004 (22)	Japan	106	39	47	P, DB	12	milk drink	3.7
Tuomilehto et al. 2004 (23)	Finland	59	52.7	61	C, DB	10	milk drink	5.2
Mizuno et al. 2005a^a (24)	Japan	41	42.6	25	P, SB	6	tablet	3.6
Mizuno et al. 2005b^a (24)	Japan	24	46.0	49	P, SB	6	tablet	3.6
Sano et al. 2005 (25)	Japan	144	50.5	40	P, DB	12	juice	3
Engberink et al. 2008a^b (11)	Netherlands	67	58.8	56	P, DB	8	milk drink	5
Engberink et al. 2008b^b (11)	Netherlands	64	54.2	52	P, DB	8	milk drink	5.1
Engberink et al. 2008c^b (11)	Netherlands	68	59.5	58	P, DB	8	milk drink	5.2
van der Zander et al. 2008a (13)	Netherlands	275	60.7	56	P, DB	8	yoghurt drink	10.2
van der Zander et al. 2008b (26)	Netherlands	42	35–70	56	C, DB	4	milk drink	8.7
de Leeuw et al. 2009 (27)	Netherlands	83	59	73	P, DB	8	yoghurt	6
van Mierlo et al. 2009 (12)	Scotland	133	62	65	C, DB	4	milk drink	5.1
Turpeinen et al. 2009 (28)	Finland	62	48	71	P, DB	10	spread	4.2
Jauhiainen et al. 2010 (29)	Finland	89	49	71	P, DB	12	milk drink	5

P = parallel study design; C = cross-over study design; DB = double-blind; SB = single-blind.

^aStudy with two arms.

^bStudy with three arms, same placebo group used.

Figure 1. Meta-analysis of the effects of IPP and VPP on systolic and diastolic blood pressure.

Figure 2. Funnel plots for systolic and diastolic blood pressure.

Table II. Methods for blood pressure measurement.

Study (reference)	Blood pressure registration
Hata et al. 1996 (14)	Office blood pressure
Kajimoto et al. 2001a (15)	Office blood pressure
Kajimoto et al. 2001b (16)	Office blood pressure
Kajimoto et al. 2002 (17)	Office blood pressure
Hirata et al. 2002 (18)	Office blood pressure
Seppo et al. 2002 (19)	Office blood pressure
Seppo et al. 2003 (20)	Home blood pressure
Mizushima et al. 2004 (21)	Office blood pressure
Nakamura et al. 2004 (22)	Office blood pressure
Tuomilehto et al. 2004 (23)	Office blood pressure
Mizuno et al. 2005a^a (24)	Office blood pressure
Mizuno et al. 2005b^a (24)	Office blood pressure
Sano et al. 2005 (25)	Office blood pressure
Engberink et al. 2008a^b (11)	Office blood pressure
Engberink et al. 2008b^b (11)	Office blood pressure
Engberink et al. 2008c^b (11)	Office blood pressure
van der Zander et al. 2008a (13)	Office blood pressure
van der Zander et al. 2008b (26)	Office blood pressure
de Leeuw et al. 2009 (27)	Office blood pressure
van Mierlo et al. 2009 (12)	Ambulatory blood pressure
Turpeinen et al. 2009 (28)	Home blood pressure
Jauhiainen et al. 2010 (29)	Office blood pressure

^a Study with two arms.

^b Study with three arms, same placebo group used.

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