Association between vitamin D and hepatitis C virus infection: A meta-analysis

Table 1 Summary of the general characteristics of the included studies regarding vitamin D and hepatitis C virus (mean ± SD)

Study	Country	Mean age (yr)	Sample Size	Design	25(OH)D measurement	Basal mean vitamin D levels (ng/mL)
Nimer et al[26]	Israel	Treated: 48 ± 14	Treated: 20 HCV infected individuals	Prospective randomized study	Radioimmunoassay (Diasorin)	Treated: 20 ± 8
		Non treated: 45 ± 10	Non treated: 30 HCV infected individuals			Non treated: 19 ± 6
Milazzo et al[25]	Italy	45	93 HIV/HCV	Retrospective case-control study (clinical samples)	Radioimmunoassay (IDS)	Cases: 23.1 (15.3-35.3)
Abu-Mouch et al[27]	Israel	Treated: 47 ± 11	Treated: 36 HCV infected individuals	Prospective randomized study	Radioimmunoassay (Diasorin)	Treated: 19 ± 6
		Non treated: 49 ± 7	Non treated: 36 HCV infected individuals			Non treated: 20.5 ± 9
Bitetto et al[20]	Italy	Treated: 56 (42-61)	Treated: 15 HCV infected individuals	Prospective randomized study	Chemiluminescence immunoassay (Diasorin)	NA
		Non treated: 52 (23-67)	Non treated: 27 HCV infected individuals
Soumekh et al[28]	United States	NA	88 HIV/HCV infected individuals	Prospective study (clinical samples)	Chemiluminescence immunoassay (Diasorin)	NA
Reiberg et al[29]	Austria	38	84 HIV/HCV infected individuals	Cohort (clinical sample)	NA	21.9 ± 13.8
Jazwinski et al[23]	United States	NA	82 HCV infected individuals	Cohort (clinical sample)	Chemiluminescence immunoassay (Diasorin)	NA
Lange et al[18]	Germany	45	468 HCV infected individuals	Cohort (clinical sample)	Radioimmunoassay (Diasorin)	17 (3-80)
Terrier et al[22]	France	39.5	189 HIV/HCV infected individuals	Cohort (clinical samples)	Radioimmunoassay (Diasorin)	18.5 ± 9.8
Bitetto et al[21]	Italy	47	211 HCV individuals	Cohort (clinical samples)	Chemiluminescence immunoassay (Diasorin)	20.7 (2.1-59.6)
Petta et al[17]	Italy	52	Cases: 196 HCV infected individuals	Transversal case-control (clinic and community sample)	HPLC	25.0 ± 9.9

NA: Not available as mean value; HCV: Hepatitis C virus; HIV: Human immunodeficiency virus; HPLC: High performance/pressure liquid chromatography; 25(OH)D: 25-hydroxyvitamin D.

Table 2 Summary of included studies regarding vitamin D and hepatitis C virus aspects

Study	Sample size	HCV genotype	Mean viral load log, (UI/mL, average)	SVR (n)	SVR1 (above/below 30 ng/mL)	Previous HCV treatment
Nimer et al[26]	50 HCV infected individuals	II:28	NA	Treated: 19/20	19/23	None
		III:22		Non treated: 23/30
Milazzo et al[25]	93 HIV/HCV infected individuals	I:66	5.8 (5.3-6.2)	21	7/14	Naïve: 31
		Non I:27				Non responder or relapser to a previous anti-HCV therapy: 20
Abou-Mouch et al[27]	72 HCV infected individuals	I:72	NA	Treated: 31	31/15	None
				Non treated: 15
Bitetto et al[20]	42 HCV infected individuals	I:32	Treated: 5 (3-7)	Treated: 8/15	6/7	All
		Non I:10	Non treated: 5 (3-7)	Non treated: 5/27
Soumekh et al[28]	88 HIV/HCV infected individuals	I or IV:77	NA	13	6/7	All
		Non I:11
Reiberg et al[29]	84 HIV/HCV infected individuals	I:47	4.5 (1.4-7.6)	39	11/28	None
		Non I:37
Jazwinski et al[23]	82 HCV infected individuals	I:82	NA	74	39/35	None
Lange et al[18]	468 HCV infected individuals	I:317	5.9 (2.3-7.7)	280	17/152	None
		I:43
		I:108
Terrier et al[22]	189 HIV/HCV infected individuals	I:84	5.9 (0-7)	61	9/52	None
		II or III:73
		IV:31
		Other 1
Bitetto et al[21]	211 HCV individuals	I:95	5 (2-7)	134	78/56	None
		II:63
		II:38
		IV-V:15
Petta et al[17]	196 HCV infected individuals	I:196	5 (2-8)	82	26/56	None

¹According to basal vitamin D cut-off or supplementation. NA: Not available as mean value; HCV: Hepatitis C virus; HIV: Human immunodeficiency virus; SVR: Sustained virological response.