Tetrahydrobiopterin Improves Endothelial Function in Cardiovascular Disease: A Systematic Review

Table 1

Basic characteristics of the included clinical trials.

Study, year	Methods	BH4-treated			Placebo
		Number	Sex (M/F)	Age	Number	Sex (M/F)	Age
Maier et al., 2000 [13]	Randomized	19	3/16	56 ± 10	*	*	*
Setoguchi et al., 2001 [22]	Randomized	15	10/5	60 ± 11	*	*	*
Nyström et al., 2004 [23]	Randomized; single-blind crossover	6	6/0	59 ± 2	6	6/0	59 ± 2
		5	5/0	57 ± 2	5	5/0	57 ± 2
		5	5/0	29 ± 4	5	5/0	29 ± 4
Worthley et al., 2007 [24]	Randomized controlled	22	4/18	60 ± 9	5	*
		25	5/20	60 ± 9	5	*
Settergren et al., 2009 [25]	Randomized; blind, crossover	12	12/0	71 ± 1.5	*
Cunnington et al., 2012 [26]	Randomized; double-blind; parallel design	30	3/27	*	19	3/16	68 ± 2
Stroes et al., 1997 [27]	Randomized controlled	13	9/4	32 ± 4	*
		13	9/4	28 ± 2	*
Fukuda et al., 2002 [30]	Randomized controlled	9	7/2	61 ± 9	*
		9	7/2	59 ± 9	*
Wyss et al., 2005 [28]	Randomized controlled	9	7/2	54 ± 8	*	*	*
		10	10/0	25 ± 3	*	*	*
Holowatz and Kenney,  2011 [29]	Randomized controlled	9	6/3	53 ± 3	*
		9	5/4	49 ± 2	*
Cosentino et al., 2008 [14]	Randomized; double-blind; parallel design	11	7/4	61 ± 9	10	10/0	54 ± 10
		9	7/2	54.4 ± 9.5	*
Higashi et al., 2002 [31]	Randomized controlled	8	6/2	48 ± 11	*
		8	6/2	44 ± 9	*
Porkert et al., 2008 [12]	Randomized	24	9/15	*	*
Heitzer et al., 2000 [15]	Randomized controlled	23	7/16	52 ± 2	*
		12	8/4	50 ± 3	*