The association between circulating 25-hydroxyvitamin D and cardiovascular diseases: a meta-analysis of prospective cohort studies

Table 2 Summary risk estimates of the association between vitamin D and risk of CVD

	N^b	Number of cases	Risk estimate (95% CI)	Heterogeneity test
	N^b	Number of cases	REM	I² (%)	P	P^a
Vitamin D	25	10,099	1.44 (1.24–1.69)	84.7	0.00
Outcome						0.11
Incidence [32, 41, 42, 44, 47, 60]	6	3338	1.18 (1–1.39)	57.7	0.03
Mortality [18, 19, 21, 39, 40, 43, 45, 46, 49,50,51,52,53,54,55,56,57,58,59]	19	6761	1.54 (1.29–1.84)	81.4	0.00
Location where the study was conducted
American [21, 44,45,46,47,48,49,50,51,52, 56, 59, 60]	13	6402	1.31 (1.12–1.54)	73.8	0.00	1
Europe [19, 39,40,41,42,43, 53,54,55, 57, 58]	11	3634	1.67 (1.27–2.19)	85.6	0.00	0.09
Others [18]	1	63	0.90 (0.50–1.61)	–	–	–
Sex						0.80
Male [39, 44, 47, 52, 54]	5	1258	1 (0.84–1.20)	0.00	0.54
Female [18, 50]	2	142	1.12 (0.78–1.59)	0.00	0.35
Quality						0.26
High [18, 21, 39, 41,42,43, 46,47,48,49,50, 52,53,54,55,56,57, 60]	18	5343	1.30 (1.16–1.46)	38.8	0.04
Moderate [19, 40, 44, 45, 51, 58, 59]	7	4756	1.58 (1.15–2.15)	92.7	0.00
Measurement of vitamin D
Radioimmunoassay [18, 19, 39, 40, 45, 50, 56, 58,59,60]	10	3924	1.61 (1.23–2.11)	82.3	0.00	1
Mass spectrometry [44, 46, 47, 49, 52, 54]	7	2100	1.08 (0.96–1.21)	8.3	0.36	0.03
Others [21, 41,42,43, 51, 53, 55, 57]	8	6024	1.45 (1.21–1.74)	72.1	0.00	0.39
Duration of follow up						0.98
< 5 years [39, 40, 47, 51]	4	1430	1.69 (1.46–1.96)	0.00	0.39
> 5 years [18, 19, 21, 41,42,43,44,45,46, 48,49,50, 52,53,54,55,56,57,58,59,60]	21	8669	1.45 (1.22–1.73)	86.7	0.00

REM random effect model
^a Pvalue for metaregression, and location where the study was conducted (American as the reference) and Measurement of vitamin D (Radioimmunoassay as the reference)
^b N: number of results

ISSN: 1471-2261